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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * A driver for the ARM PL022 PrimeCell SSP/SPI bus master.
4 *
5 * Copyright (C) 2008-2012 ST-Ericsson AB
6 * Copyright (C) 2006 STMicroelectronics Pvt. Ltd.
7 *
8 * Author: Linus Walleij <linus.walleij@stericsson.com>
9 *
10 * Initial version inspired by:
11 * linux-2.6.17-rc3-mm1/drivers/spi/pxa2xx_spi.c
12 * Initial adoption to PL022 by:
13 * Sachin Verma <sachin.verma@st.com>
14 */
15
16#include <linux/init.h>
17#include <linux/module.h>
18#include <linux/device.h>
19#include <linux/ioport.h>
20#include <linux/errno.h>
21#include <linux/interrupt.h>
22#include <linux/spi/spi.h>
23#include <linux/delay.h>
24#include <linux/clk.h>
25#include <linux/err.h>
26#include <linux/amba/bus.h>
27#include <linux/amba/pl022.h>
28#include <linux/io.h>
29#include <linux/slab.h>
30#include <linux/dmaengine.h>
31#include <linux/dma-mapping.h>
32#include <linux/scatterlist.h>
33#include <linux/pm_runtime.h>
34#include <linux/gpio.h>
35#include <linux/of_gpio.h>
36#include <linux/pinctrl/consumer.h>
37
38/*
39 * This macro is used to define some register default values.
40 * reg is masked with mask, the OR:ed with an (again masked)
41 * val shifted sb steps to the left.
42 */
43#define SSP_WRITE_BITS(reg, val, mask, sb) \
44 ((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask))))
45
46/*
47 * This macro is also used to define some default values.
48 * It will just shift val by sb steps to the left and mask
49 * the result with mask.
50 */
51#define GEN_MASK_BITS(val, mask, sb) \
52 (((val)<<(sb)) & (mask))
53
54#define DRIVE_TX 0
55#define DO_NOT_DRIVE_TX 1
56
57#define DO_NOT_QUEUE_DMA 0
58#define QUEUE_DMA 1
59
60#define RX_TRANSFER 1
61#define TX_TRANSFER 2
62
63/*
64 * Macros to access SSP Registers with their offsets
65 */
66#define SSP_CR0(r) (r + 0x000)
67#define SSP_CR1(r) (r + 0x004)
68#define SSP_DR(r) (r + 0x008)
69#define SSP_SR(r) (r + 0x00C)
70#define SSP_CPSR(r) (r + 0x010)
71#define SSP_IMSC(r) (r + 0x014)
72#define SSP_RIS(r) (r + 0x018)
73#define SSP_MIS(r) (r + 0x01C)
74#define SSP_ICR(r) (r + 0x020)
75#define SSP_DMACR(r) (r + 0x024)
76#define SSP_CSR(r) (r + 0x030) /* vendor extension */
77#define SSP_ITCR(r) (r + 0x080)
78#define SSP_ITIP(r) (r + 0x084)
79#define SSP_ITOP(r) (r + 0x088)
80#define SSP_TDR(r) (r + 0x08C)
81
82#define SSP_PID0(r) (r + 0xFE0)
83#define SSP_PID1(r) (r + 0xFE4)
84#define SSP_PID2(r) (r + 0xFE8)
85#define SSP_PID3(r) (r + 0xFEC)
86
87#define SSP_CID0(r) (r + 0xFF0)
88#define SSP_CID1(r) (r + 0xFF4)
89#define SSP_CID2(r) (r + 0xFF8)
90#define SSP_CID3(r) (r + 0xFFC)
91
92/*
93 * SSP Control Register 0 - SSP_CR0
94 */
95#define SSP_CR0_MASK_DSS (0x0FUL << 0)
96#define SSP_CR0_MASK_FRF (0x3UL << 4)
97#define SSP_CR0_MASK_SPO (0x1UL << 6)
98#define SSP_CR0_MASK_SPH (0x1UL << 7)
99#define SSP_CR0_MASK_SCR (0xFFUL << 8)
100
101/*
102 * The ST version of this block moves som bits
103 * in SSP_CR0 and extends it to 32 bits
104 */
105#define SSP_CR0_MASK_DSS_ST (0x1FUL << 0)
106#define SSP_CR0_MASK_HALFDUP_ST (0x1UL << 5)
107#define SSP_CR0_MASK_CSS_ST (0x1FUL << 16)
108#define SSP_CR0_MASK_FRF_ST (0x3UL << 21)
109
110/*
111 * SSP Control Register 0 - SSP_CR1
112 */
113#define SSP_CR1_MASK_LBM (0x1UL << 0)
114#define SSP_CR1_MASK_SSE (0x1UL << 1)
115#define SSP_CR1_MASK_MS (0x1UL << 2)
116#define SSP_CR1_MASK_SOD (0x1UL << 3)
117
118/*
119 * The ST version of this block adds some bits
120 * in SSP_CR1
121 */
122#define SSP_CR1_MASK_RENDN_ST (0x1UL << 4)
123#define SSP_CR1_MASK_TENDN_ST (0x1UL << 5)
124#define SSP_CR1_MASK_MWAIT_ST (0x1UL << 6)
125#define SSP_CR1_MASK_RXIFLSEL_ST (0x7UL << 7)
126#define SSP_CR1_MASK_TXIFLSEL_ST (0x7UL << 10)
127/* This one is only in the PL023 variant */
128#define SSP_CR1_MASK_FBCLKDEL_ST (0x7UL << 13)
129
130/*
131 * SSP Status Register - SSP_SR
132 */
133#define SSP_SR_MASK_TFE (0x1UL << 0) /* Transmit FIFO empty */
134#define SSP_SR_MASK_TNF (0x1UL << 1) /* Transmit FIFO not full */
135#define SSP_SR_MASK_RNE (0x1UL << 2) /* Receive FIFO not empty */
136#define SSP_SR_MASK_RFF (0x1UL << 3) /* Receive FIFO full */
137#define SSP_SR_MASK_BSY (0x1UL << 4) /* Busy Flag */
138
139/*
140 * SSP Clock Prescale Register - SSP_CPSR
141 */
142#define SSP_CPSR_MASK_CPSDVSR (0xFFUL << 0)
143
144/*
145 * SSP Interrupt Mask Set/Clear Register - SSP_IMSC
146 */
147#define SSP_IMSC_MASK_RORIM (0x1UL << 0) /* Receive Overrun Interrupt mask */
148#define SSP_IMSC_MASK_RTIM (0x1UL << 1) /* Receive timeout Interrupt mask */
149#define SSP_IMSC_MASK_RXIM (0x1UL << 2) /* Receive FIFO Interrupt mask */
150#define SSP_IMSC_MASK_TXIM (0x1UL << 3) /* Transmit FIFO Interrupt mask */
151
152/*
153 * SSP Raw Interrupt Status Register - SSP_RIS
154 */
155/* Receive Overrun Raw Interrupt status */
156#define SSP_RIS_MASK_RORRIS (0x1UL << 0)
157/* Receive Timeout Raw Interrupt status */
158#define SSP_RIS_MASK_RTRIS (0x1UL << 1)
159/* Receive FIFO Raw Interrupt status */
160#define SSP_RIS_MASK_RXRIS (0x1UL << 2)
161/* Transmit FIFO Raw Interrupt status */
162#define SSP_RIS_MASK_TXRIS (0x1UL << 3)
163
164/*
165 * SSP Masked Interrupt Status Register - SSP_MIS
166 */
167/* Receive Overrun Masked Interrupt status */
168#define SSP_MIS_MASK_RORMIS (0x1UL << 0)
169/* Receive Timeout Masked Interrupt status */
170#define SSP_MIS_MASK_RTMIS (0x1UL << 1)
171/* Receive FIFO Masked Interrupt status */
172#define SSP_MIS_MASK_RXMIS (0x1UL << 2)
173/* Transmit FIFO Masked Interrupt status */
174#define SSP_MIS_MASK_TXMIS (0x1UL << 3)
175
176/*
177 * SSP Interrupt Clear Register - SSP_ICR
178 */
179/* Receive Overrun Raw Clear Interrupt bit */
180#define SSP_ICR_MASK_RORIC (0x1UL << 0)
181/* Receive Timeout Clear Interrupt bit */
182#define SSP_ICR_MASK_RTIC (0x1UL << 1)
183
184/*
185 * SSP DMA Control Register - SSP_DMACR
186 */
187/* Receive DMA Enable bit */
188#define SSP_DMACR_MASK_RXDMAE (0x1UL << 0)
189/* Transmit DMA Enable bit */
190#define SSP_DMACR_MASK_TXDMAE (0x1UL << 1)
191
192/*
193 * SSP Chip Select Control Register - SSP_CSR
194 * (vendor extension)
195 */
196#define SSP_CSR_CSVALUE_MASK (0x1FUL << 0)
197
198/*
199 * SSP Integration Test control Register - SSP_ITCR
200 */
201#define SSP_ITCR_MASK_ITEN (0x1UL << 0)
202#define SSP_ITCR_MASK_TESTFIFO (0x1UL << 1)
203
204/*
205 * SSP Integration Test Input Register - SSP_ITIP
206 */
207#define ITIP_MASK_SSPRXD (0x1UL << 0)
208#define ITIP_MASK_SSPFSSIN (0x1UL << 1)
209#define ITIP_MASK_SSPCLKIN (0x1UL << 2)
210#define ITIP_MASK_RXDMAC (0x1UL << 3)
211#define ITIP_MASK_TXDMAC (0x1UL << 4)
212#define ITIP_MASK_SSPTXDIN (0x1UL << 5)
213
214/*
215 * SSP Integration Test output Register - SSP_ITOP
216 */
217#define ITOP_MASK_SSPTXD (0x1UL << 0)
218#define ITOP_MASK_SSPFSSOUT (0x1UL << 1)
219#define ITOP_MASK_SSPCLKOUT (0x1UL << 2)
220#define ITOP_MASK_SSPOEn (0x1UL << 3)
221#define ITOP_MASK_SSPCTLOEn (0x1UL << 4)
222#define ITOP_MASK_RORINTR (0x1UL << 5)
223#define ITOP_MASK_RTINTR (0x1UL << 6)
224#define ITOP_MASK_RXINTR (0x1UL << 7)
225#define ITOP_MASK_TXINTR (0x1UL << 8)
226#define ITOP_MASK_INTR (0x1UL << 9)
227#define ITOP_MASK_RXDMABREQ (0x1UL << 10)
228#define ITOP_MASK_RXDMASREQ (0x1UL << 11)
229#define ITOP_MASK_TXDMABREQ (0x1UL << 12)
230#define ITOP_MASK_TXDMASREQ (0x1UL << 13)
231
232/*
233 * SSP Test Data Register - SSP_TDR
234 */
235#define TDR_MASK_TESTDATA (0xFFFFFFFF)
236
237/*
238 * Message State
239 * we use the spi_message.state (void *) pointer to
240 * hold a single state value, that's why all this
241 * (void *) casting is done here.
242 */
243#define STATE_START ((void *) 0)
244#define STATE_RUNNING ((void *) 1)
245#define STATE_DONE ((void *) 2)
246#define STATE_ERROR ((void *) -1)
247#define STATE_TIMEOUT ((void *) -2)
248
249/*
250 * SSP State - Whether Enabled or Disabled
251 */
252#define SSP_DISABLED (0)
253#define SSP_ENABLED (1)
254
255/*
256 * SSP DMA State - Whether DMA Enabled or Disabled
257 */
258#define SSP_DMA_DISABLED (0)
259#define SSP_DMA_ENABLED (1)
260
261/*
262 * SSP Clock Defaults
263 */
264#define SSP_DEFAULT_CLKRATE 0x2
265#define SSP_DEFAULT_PRESCALE 0x40
266
267/*
268 * SSP Clock Parameter ranges
269 */
270#define CPSDVR_MIN 0x02
271#define CPSDVR_MAX 0xFE
272#define SCR_MIN 0x00
273#define SCR_MAX 0xFF
274
275/*
276 * SSP Interrupt related Macros
277 */
278#define DEFAULT_SSP_REG_IMSC 0x0UL
279#define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC
280#define ENABLE_ALL_INTERRUPTS ( \
281 SSP_IMSC_MASK_RORIM | \
282 SSP_IMSC_MASK_RTIM | \
283 SSP_IMSC_MASK_RXIM | \
284 SSP_IMSC_MASK_TXIM \
285)
286
287#define CLEAR_ALL_INTERRUPTS 0x3
288
289#define SPI_POLLING_TIMEOUT 1000
290
291/*
292 * The type of reading going on on this chip
293 */
294enum ssp_reading {
295 READING_NULL,
296 READING_U8,
297 READING_U16,
298 READING_U32
299};
300
301/*
302 * The type of writing going on on this chip
303 */
304enum ssp_writing {
305 WRITING_NULL,
306 WRITING_U8,
307 WRITING_U16,
308 WRITING_U32
309};
310
311/**
312 * struct vendor_data - vendor-specific config parameters
313 * for PL022 derivates
314 * @fifodepth: depth of FIFOs (both)
315 * @max_bpw: maximum number of bits per word
316 * @unidir: supports unidirection transfers
317 * @extended_cr: 32 bit wide control register 0 with extra
318 * features and extra features in CR1 as found in the ST variants
319 * @pl023: supports a subset of the ST extensions called "PL023"
320 * @loopback: supports loopback mode
321 * @internal_cs_ctrl: supports chip select control register
322 */
323struct vendor_data {
324 int fifodepth;
325 int max_bpw;
326 bool unidir;
327 bool extended_cr;
328 bool pl023;
329 bool loopback;
330 bool internal_cs_ctrl;
331};
332
333/**
334 * struct pl022 - This is the private SSP driver data structure
335 * @adev: AMBA device model hookup
336 * @vendor: vendor data for the IP block
337 * @phybase: the physical memory where the SSP device resides
338 * @virtbase: the virtual memory where the SSP is mapped
339 * @clk: outgoing clock "SPICLK" for the SPI bus
340 * @master: SPI framework hookup
341 * @master_info: controller-specific data from machine setup
342 * @pump_transfers: Tasklet used in Interrupt Transfer mode
343 * @cur_msg: Pointer to current spi_message being processed
344 * @cur_transfer: Pointer to current spi_transfer
345 * @cur_chip: pointer to current clients chip(assigned from controller_state)
346 * @next_msg_cs_active: the next message in the queue has been examined
347 * and it was found that it uses the same chip select as the previous
348 * message, so we left it active after the previous transfer, and it's
349 * active already.
350 * @tx: current position in TX buffer to be read
351 * @tx_end: end position in TX buffer to be read
352 * @rx: current position in RX buffer to be written
353 * @rx_end: end position in RX buffer to be written
354 * @read: the type of read currently going on
355 * @write: the type of write currently going on
356 * @exp_fifo_level: expected FIFO level
357 * @rx_lev_trig: receive FIFO watermark level which triggers IRQ
358 * @tx_lev_trig: transmit FIFO watermark level which triggers IRQ
359 * @dma_rx_channel: optional channel for RX DMA
360 * @dma_tx_channel: optional channel for TX DMA
361 * @sgt_rx: scattertable for the RX transfer
362 * @sgt_tx: scattertable for the TX transfer
363 * @dummypage: a dummy page used for driving data on the bus with DMA
364 * @dma_running: indicates whether DMA is in operation
365 * @cur_cs: current chip select (gpio)
366 * @chipselects: list of chipselects (gpios)
367 */
368struct pl022 {
369 struct amba_device *adev;
370 struct vendor_data *vendor;
371 resource_size_t phybase;
372 void __iomem *virtbase;
373 struct clk *clk;
374 struct spi_master *master;
375 struct pl022_ssp_controller *master_info;
376 /* Message per-transfer pump */
377 struct tasklet_struct pump_transfers;
378 struct spi_message *cur_msg;
379 struct spi_transfer *cur_transfer;
380 struct chip_data *cur_chip;
381 bool next_msg_cs_active;
382 void *tx;
383 void *tx_end;
384 void *rx;
385 void *rx_end;
386 enum ssp_reading read;
387 enum ssp_writing write;
388 u32 exp_fifo_level;
389 enum ssp_rx_level_trig rx_lev_trig;
390 enum ssp_tx_level_trig tx_lev_trig;
391 /* DMA settings */
392#ifdef CONFIG_DMA_ENGINE
393 struct dma_chan *dma_rx_channel;
394 struct dma_chan *dma_tx_channel;
395 struct sg_table sgt_rx;
396 struct sg_table sgt_tx;
397 char *dummypage;
398 bool dma_running;
399#endif
400 int cur_cs;
401 int *chipselects;
402};
403
404/**
405 * struct chip_data - To maintain runtime state of SSP for each client chip
406 * @cr0: Value of control register CR0 of SSP - on later ST variants this
407 * register is 32 bits wide rather than just 16
408 * @cr1: Value of control register CR1 of SSP
409 * @dmacr: Value of DMA control Register of SSP
410 * @cpsr: Value of Clock prescale register
411 * @n_bytes: how many bytes(power of 2) reqd for a given data width of client
412 * @enable_dma: Whether to enable DMA or not
413 * @read: function ptr to be used to read when doing xfer for this chip
414 * @write: function ptr to be used to write when doing xfer for this chip
415 * @cs_control: chip select callback provided by chip
416 * @xfer_type: polling/interrupt/DMA
417 *
418 * Runtime state of the SSP controller, maintained per chip,
419 * This would be set according to the current message that would be served
420 */
421struct chip_data {
422 u32 cr0;
423 u16 cr1;
424 u16 dmacr;
425 u16 cpsr;
426 u8 n_bytes;
427 bool enable_dma;
428 enum ssp_reading read;
429 enum ssp_writing write;
430 void (*cs_control) (u32 command);
431 int xfer_type;
432};
433
434/**
435 * null_cs_control - Dummy chip select function
436 * @command: select/delect the chip
437 *
438 * If no chip select function is provided by client this is used as dummy
439 * chip select
440 */
441static void null_cs_control(u32 command)
442{
443 pr_debug("pl022: dummy chip select control, CS=0x%x\n", command);
444}
445
446/**
447 * internal_cs_control - Control chip select signals via SSP_CSR.
448 * @pl022: SSP driver private data structure
449 * @command: select/delect the chip
450 *
451 * Used on controller with internal chip select control via SSP_CSR register
452 * (vendor extension). Each of the 5 LSB in the register controls one chip
453 * select signal.
454 */
455static void internal_cs_control(struct pl022 *pl022, u32 command)
456{
457 u32 tmp;
458
459 tmp = readw(SSP_CSR(pl022->virtbase));
460 if (command == SSP_CHIP_SELECT)
461 tmp &= ~BIT(pl022->cur_cs);
462 else
463 tmp |= BIT(pl022->cur_cs);
464 writew(tmp, SSP_CSR(pl022->virtbase));
465}
466
467static void pl022_cs_control(struct pl022 *pl022, u32 command)
468{
469 if (pl022->vendor->internal_cs_ctrl)
470 internal_cs_control(pl022, command);
471 else if (gpio_is_valid(pl022->cur_cs))
472 gpio_set_value(pl022->cur_cs, command);
473 else
474 pl022->cur_chip->cs_control(command);
475}
476
477/**
478 * giveback - current spi_message is over, schedule next message and call
479 * callback of this message. Assumes that caller already
480 * set message->status; dma and pio irqs are blocked
481 * @pl022: SSP driver private data structure
482 */
483static void giveback(struct pl022 *pl022)
484{
485 struct spi_transfer *last_transfer;
486 pl022->next_msg_cs_active = false;
487
488 last_transfer = list_last_entry(&pl022->cur_msg->transfers,
489 struct spi_transfer, transfer_list);
490
491 /* Delay if requested before any change in chip select */
492 /*
493 * FIXME: This runs in interrupt context.
494 * Is this really smart?
495 */
496 spi_transfer_delay_exec(last_transfer);
497
498 if (!last_transfer->cs_change) {
499 struct spi_message *next_msg;
500
501 /*
502 * cs_change was not set. We can keep the chip select
503 * enabled if there is message in the queue and it is
504 * for the same spi device.
505 *
506 * We cannot postpone this until pump_messages, because
507 * after calling msg->complete (below) the driver that
508 * sent the current message could be unloaded, which
509 * could invalidate the cs_control() callback...
510 */
511 /* get a pointer to the next message, if any */
512 next_msg = spi_get_next_queued_message(pl022->master);
513
514 /*
515 * see if the next and current messages point
516 * to the same spi device.
517 */
518 if (next_msg && next_msg->spi != pl022->cur_msg->spi)
519 next_msg = NULL;
520 if (!next_msg || pl022->cur_msg->state == STATE_ERROR)
521 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
522 else
523 pl022->next_msg_cs_active = true;
524
525 }
526
527 pl022->cur_msg = NULL;
528 pl022->cur_transfer = NULL;
529 pl022->cur_chip = NULL;
530
531 /* disable the SPI/SSP operation */
532 writew((readw(SSP_CR1(pl022->virtbase)) &
533 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
534
535 spi_finalize_current_message(pl022->master);
536}
537
538/**
539 * flush - flush the FIFO to reach a clean state
540 * @pl022: SSP driver private data structure
541 */
542static int flush(struct pl022 *pl022)
543{
544 unsigned long limit = loops_per_jiffy << 1;
545
546 dev_dbg(&pl022->adev->dev, "flush\n");
547 do {
548 while (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
549 readw(SSP_DR(pl022->virtbase));
550 } while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_BSY) && limit--);
551
552 pl022->exp_fifo_level = 0;
553
554 return limit;
555}
556
557/**
558 * restore_state - Load configuration of current chip
559 * @pl022: SSP driver private data structure
560 */
561static void restore_state(struct pl022 *pl022)
562{
563 struct chip_data *chip = pl022->cur_chip;
564
565 if (pl022->vendor->extended_cr)
566 writel(chip->cr0, SSP_CR0(pl022->virtbase));
567 else
568 writew(chip->cr0, SSP_CR0(pl022->virtbase));
569 writew(chip->cr1, SSP_CR1(pl022->virtbase));
570 writew(chip->dmacr, SSP_DMACR(pl022->virtbase));
571 writew(chip->cpsr, SSP_CPSR(pl022->virtbase));
572 writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
573 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
574}
575
576/*
577 * Default SSP Register Values
578 */
579#define DEFAULT_SSP_REG_CR0 ( \
580 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0) | \
581 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 4) | \
582 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
583 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
584 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
585)
586
587/* ST versions have slightly different bit layout */
588#define DEFAULT_SSP_REG_CR0_ST ( \
589 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
590 GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, SSP_CR0_MASK_HALFDUP_ST, 5) | \
591 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
592 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
593 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \
594 GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS_ST, 16) | \
595 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF_ST, 21) \
596)
597
598/* The PL023 version is slightly different again */
599#define DEFAULT_SSP_REG_CR0_ST_PL023 ( \
600 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
601 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
602 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
603 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
604)
605
606#define DEFAULT_SSP_REG_CR1 ( \
607 GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \
608 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
609 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
610 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) \
611)
612
613/* ST versions extend this register to use all 16 bits */
614#define DEFAULT_SSP_REG_CR1_ST ( \
615 DEFAULT_SSP_REG_CR1 | \
616 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
617 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
618 GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT_ST, 6) |\
619 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
620 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) \
621)
622
623/*
624 * The PL023 variant has further differences: no loopback mode, no microwire
625 * support, and a new clock feedback delay setting.
626 */
627#define DEFAULT_SSP_REG_CR1_ST_PL023 ( \
628 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
629 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
630 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \
631 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
632 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
633 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
634 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) | \
635 GEN_MASK_BITS(SSP_FEEDBACK_CLK_DELAY_NONE, SSP_CR1_MASK_FBCLKDEL_ST, 13) \
636)
637
638#define DEFAULT_SSP_REG_CPSR ( \
639 GEN_MASK_BITS(SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \
640)
641
642#define DEFAULT_SSP_REG_DMACR (\
643 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \
644 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \
645)
646
647/**
648 * load_ssp_default_config - Load default configuration for SSP
649 * @pl022: SSP driver private data structure
650 */
651static void load_ssp_default_config(struct pl022 *pl022)
652{
653 if (pl022->vendor->pl023) {
654 writel(DEFAULT_SSP_REG_CR0_ST_PL023, SSP_CR0(pl022->virtbase));
655 writew(DEFAULT_SSP_REG_CR1_ST_PL023, SSP_CR1(pl022->virtbase));
656 } else if (pl022->vendor->extended_cr) {
657 writel(DEFAULT_SSP_REG_CR0_ST, SSP_CR0(pl022->virtbase));
658 writew(DEFAULT_SSP_REG_CR1_ST, SSP_CR1(pl022->virtbase));
659 } else {
660 writew(DEFAULT_SSP_REG_CR0, SSP_CR0(pl022->virtbase));
661 writew(DEFAULT_SSP_REG_CR1, SSP_CR1(pl022->virtbase));
662 }
663 writew(DEFAULT_SSP_REG_DMACR, SSP_DMACR(pl022->virtbase));
664 writew(DEFAULT_SSP_REG_CPSR, SSP_CPSR(pl022->virtbase));
665 writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
666 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
667}
668
669/*
670 * This will write to TX and read from RX according to the parameters
671 * set in pl022.
672 */
673static void readwriter(struct pl022 *pl022)
674{
675
676 /*
677 * The FIFO depth is different between primecell variants.
678 * I believe filling in too much in the FIFO might cause
679 * errons in 8bit wide transfers on ARM variants (just 8 words
680 * FIFO, means only 8x8 = 64 bits in FIFO) at least.
681 *
682 * To prevent this issue, the TX FIFO is only filled to the
683 * unused RX FIFO fill length, regardless of what the TX
684 * FIFO status flag indicates.
685 */
686 dev_dbg(&pl022->adev->dev,
687 "%s, rx: %p, rxend: %p, tx: %p, txend: %p\n",
688 __func__, pl022->rx, pl022->rx_end, pl022->tx, pl022->tx_end);
689
690 /* Read as much as you can */
691 while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
692 && (pl022->rx < pl022->rx_end)) {
693 switch (pl022->read) {
694 case READING_NULL:
695 readw(SSP_DR(pl022->virtbase));
696 break;
697 case READING_U8:
698 *(u8 *) (pl022->rx) =
699 readw(SSP_DR(pl022->virtbase)) & 0xFFU;
700 break;
701 case READING_U16:
702 *(u16 *) (pl022->rx) =
703 (u16) readw(SSP_DR(pl022->virtbase));
704 break;
705 case READING_U32:
706 *(u32 *) (pl022->rx) =
707 readl(SSP_DR(pl022->virtbase));
708 break;
709 }
710 pl022->rx += (pl022->cur_chip->n_bytes);
711 pl022->exp_fifo_level--;
712 }
713 /*
714 * Write as much as possible up to the RX FIFO size
715 */
716 while ((pl022->exp_fifo_level < pl022->vendor->fifodepth)
717 && (pl022->tx < pl022->tx_end)) {
718 switch (pl022->write) {
719 case WRITING_NULL:
720 writew(0x0, SSP_DR(pl022->virtbase));
721 break;
722 case WRITING_U8:
723 writew(*(u8 *) (pl022->tx), SSP_DR(pl022->virtbase));
724 break;
725 case WRITING_U16:
726 writew((*(u16 *) (pl022->tx)), SSP_DR(pl022->virtbase));
727 break;
728 case WRITING_U32:
729 writel(*(u32 *) (pl022->tx), SSP_DR(pl022->virtbase));
730 break;
731 }
732 pl022->tx += (pl022->cur_chip->n_bytes);
733 pl022->exp_fifo_level++;
734 /*
735 * This inner reader takes care of things appearing in the RX
736 * FIFO as we're transmitting. This will happen a lot since the
737 * clock starts running when you put things into the TX FIFO,
738 * and then things are continuously clocked into the RX FIFO.
739 */
740 while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
741 && (pl022->rx < pl022->rx_end)) {
742 switch (pl022->read) {
743 case READING_NULL:
744 readw(SSP_DR(pl022->virtbase));
745 break;
746 case READING_U8:
747 *(u8 *) (pl022->rx) =
748 readw(SSP_DR(pl022->virtbase)) & 0xFFU;
749 break;
750 case READING_U16:
751 *(u16 *) (pl022->rx) =
752 (u16) readw(SSP_DR(pl022->virtbase));
753 break;
754 case READING_U32:
755 *(u32 *) (pl022->rx) =
756 readl(SSP_DR(pl022->virtbase));
757 break;
758 }
759 pl022->rx += (pl022->cur_chip->n_bytes);
760 pl022->exp_fifo_level--;
761 }
762 }
763 /*
764 * When we exit here the TX FIFO should be full and the RX FIFO
765 * should be empty
766 */
767}
768
769/**
770 * next_transfer - Move to the Next transfer in the current spi message
771 * @pl022: SSP driver private data structure
772 *
773 * This function moves though the linked list of spi transfers in the
774 * current spi message and returns with the state of current spi
775 * message i.e whether its last transfer is done(STATE_DONE) or
776 * Next transfer is ready(STATE_RUNNING)
777 */
778static void *next_transfer(struct pl022 *pl022)
779{
780 struct spi_message *msg = pl022->cur_msg;
781 struct spi_transfer *trans = pl022->cur_transfer;
782
783 /* Move to next transfer */
784 if (trans->transfer_list.next != &msg->transfers) {
785 pl022->cur_transfer =
786 list_entry(trans->transfer_list.next,
787 struct spi_transfer, transfer_list);
788 return STATE_RUNNING;
789 }
790 return STATE_DONE;
791}
792
793/*
794 * This DMA functionality is only compiled in if we have
795 * access to the generic DMA devices/DMA engine.
796 */
797#ifdef CONFIG_DMA_ENGINE
798static void unmap_free_dma_scatter(struct pl022 *pl022)
799{
800 /* Unmap and free the SG tables */
801 dma_unmap_sg(pl022->dma_tx_channel->device->dev, pl022->sgt_tx.sgl,
802 pl022->sgt_tx.nents, DMA_TO_DEVICE);
803 dma_unmap_sg(pl022->dma_rx_channel->device->dev, pl022->sgt_rx.sgl,
804 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
805 sg_free_table(&pl022->sgt_rx);
806 sg_free_table(&pl022->sgt_tx);
807}
808
809static void dma_callback(void *data)
810{
811 struct pl022 *pl022 = data;
812 struct spi_message *msg = pl022->cur_msg;
813
814 BUG_ON(!pl022->sgt_rx.sgl);
815
816#ifdef VERBOSE_DEBUG
817 /*
818 * Optionally dump out buffers to inspect contents, this is
819 * good if you want to convince yourself that the loopback
820 * read/write contents are the same, when adopting to a new
821 * DMA engine.
822 */
823 {
824 struct scatterlist *sg;
825 unsigned int i;
826
827 dma_sync_sg_for_cpu(&pl022->adev->dev,
828 pl022->sgt_rx.sgl,
829 pl022->sgt_rx.nents,
830 DMA_FROM_DEVICE);
831
832 for_each_sg(pl022->sgt_rx.sgl, sg, pl022->sgt_rx.nents, i) {
833 dev_dbg(&pl022->adev->dev, "SPI RX SG ENTRY: %d", i);
834 print_hex_dump(KERN_ERR, "SPI RX: ",
835 DUMP_PREFIX_OFFSET,
836 16,
837 1,
838 sg_virt(sg),
839 sg_dma_len(sg),
840 1);
841 }
842 for_each_sg(pl022->sgt_tx.sgl, sg, pl022->sgt_tx.nents, i) {
843 dev_dbg(&pl022->adev->dev, "SPI TX SG ENTRY: %d", i);
844 print_hex_dump(KERN_ERR, "SPI TX: ",
845 DUMP_PREFIX_OFFSET,
846 16,
847 1,
848 sg_virt(sg),
849 sg_dma_len(sg),
850 1);
851 }
852 }
853#endif
854
855 unmap_free_dma_scatter(pl022);
856
857 /* Update total bytes transferred */
858 msg->actual_length += pl022->cur_transfer->len;
859 /* Move to next transfer */
860 msg->state = next_transfer(pl022);
861 if (msg->state != STATE_DONE && pl022->cur_transfer->cs_change)
862 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
863 tasklet_schedule(&pl022->pump_transfers);
864}
865
866static void setup_dma_scatter(struct pl022 *pl022,
867 void *buffer,
868 unsigned int length,
869 struct sg_table *sgtab)
870{
871 struct scatterlist *sg;
872 int bytesleft = length;
873 void *bufp = buffer;
874 int mapbytes;
875 int i;
876
877 if (buffer) {
878 for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
879 /*
880 * If there are less bytes left than what fits
881 * in the current page (plus page alignment offset)
882 * we just feed in this, else we stuff in as much
883 * as we can.
884 */
885 if (bytesleft < (PAGE_SIZE - offset_in_page(bufp)))
886 mapbytes = bytesleft;
887 else
888 mapbytes = PAGE_SIZE - offset_in_page(bufp);
889 sg_set_page(sg, virt_to_page(bufp),
890 mapbytes, offset_in_page(bufp));
891 bufp += mapbytes;
892 bytesleft -= mapbytes;
893 dev_dbg(&pl022->adev->dev,
894 "set RX/TX target page @ %p, %d bytes, %d left\n",
895 bufp, mapbytes, bytesleft);
896 }
897 } else {
898 /* Map the dummy buffer on every page */
899 for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
900 if (bytesleft < PAGE_SIZE)
901 mapbytes = bytesleft;
902 else
903 mapbytes = PAGE_SIZE;
904 sg_set_page(sg, virt_to_page(pl022->dummypage),
905 mapbytes, 0);
906 bytesleft -= mapbytes;
907 dev_dbg(&pl022->adev->dev,
908 "set RX/TX to dummy page %d bytes, %d left\n",
909 mapbytes, bytesleft);
910
911 }
912 }
913 BUG_ON(bytesleft);
914}
915
916/**
917 * configure_dma - configures the channels for the next transfer
918 * @pl022: SSP driver's private data structure
919 */
920static int configure_dma(struct pl022 *pl022)
921{
922 struct dma_slave_config rx_conf = {
923 .src_addr = SSP_DR(pl022->phybase),
924 .direction = DMA_DEV_TO_MEM,
925 .device_fc = false,
926 };
927 struct dma_slave_config tx_conf = {
928 .dst_addr = SSP_DR(pl022->phybase),
929 .direction = DMA_MEM_TO_DEV,
930 .device_fc = false,
931 };
932 unsigned int pages;
933 int ret;
934 int rx_sglen, tx_sglen;
935 struct dma_chan *rxchan = pl022->dma_rx_channel;
936 struct dma_chan *txchan = pl022->dma_tx_channel;
937 struct dma_async_tx_descriptor *rxdesc;
938 struct dma_async_tx_descriptor *txdesc;
939
940 /* Check that the channels are available */
941 if (!rxchan || !txchan)
942 return -ENODEV;
943
944 /*
945 * If supplied, the DMA burstsize should equal the FIFO trigger level.
946 * Notice that the DMA engine uses one-to-one mapping. Since we can
947 * not trigger on 2 elements this needs explicit mapping rather than
948 * calculation.
949 */
950 switch (pl022->rx_lev_trig) {
951 case SSP_RX_1_OR_MORE_ELEM:
952 rx_conf.src_maxburst = 1;
953 break;
954 case SSP_RX_4_OR_MORE_ELEM:
955 rx_conf.src_maxburst = 4;
956 break;
957 case SSP_RX_8_OR_MORE_ELEM:
958 rx_conf.src_maxburst = 8;
959 break;
960 case SSP_RX_16_OR_MORE_ELEM:
961 rx_conf.src_maxburst = 16;
962 break;
963 case SSP_RX_32_OR_MORE_ELEM:
964 rx_conf.src_maxburst = 32;
965 break;
966 default:
967 rx_conf.src_maxburst = pl022->vendor->fifodepth >> 1;
968 break;
969 }
970
971 switch (pl022->tx_lev_trig) {
972 case SSP_TX_1_OR_MORE_EMPTY_LOC:
973 tx_conf.dst_maxburst = 1;
974 break;
975 case SSP_TX_4_OR_MORE_EMPTY_LOC:
976 tx_conf.dst_maxburst = 4;
977 break;
978 case SSP_TX_8_OR_MORE_EMPTY_LOC:
979 tx_conf.dst_maxburst = 8;
980 break;
981 case SSP_TX_16_OR_MORE_EMPTY_LOC:
982 tx_conf.dst_maxburst = 16;
983 break;
984 case SSP_TX_32_OR_MORE_EMPTY_LOC:
985 tx_conf.dst_maxburst = 32;
986 break;
987 default:
988 tx_conf.dst_maxburst = pl022->vendor->fifodepth >> 1;
989 break;
990 }
991
992 switch (pl022->read) {
993 case READING_NULL:
994 /* Use the same as for writing */
995 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
996 break;
997 case READING_U8:
998 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
999 break;
1000 case READING_U16:
1001 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
1002 break;
1003 case READING_U32:
1004 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1005 break;
1006 }
1007
1008 switch (pl022->write) {
1009 case WRITING_NULL:
1010 /* Use the same as for reading */
1011 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
1012 break;
1013 case WRITING_U8:
1014 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1015 break;
1016 case WRITING_U16:
1017 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
1018 break;
1019 case WRITING_U32:
1020 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1021 break;
1022 }
1023
1024 /* SPI pecularity: we need to read and write the same width */
1025 if (rx_conf.src_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
1026 rx_conf.src_addr_width = tx_conf.dst_addr_width;
1027 if (tx_conf.dst_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
1028 tx_conf.dst_addr_width = rx_conf.src_addr_width;
1029 BUG_ON(rx_conf.src_addr_width != tx_conf.dst_addr_width);
1030
1031 dmaengine_slave_config(rxchan, &rx_conf);
1032 dmaengine_slave_config(txchan, &tx_conf);
1033
1034 /* Create sglists for the transfers */
1035 pages = DIV_ROUND_UP(pl022->cur_transfer->len, PAGE_SIZE);
1036 dev_dbg(&pl022->adev->dev, "using %d pages for transfer\n", pages);
1037
1038 ret = sg_alloc_table(&pl022->sgt_rx, pages, GFP_ATOMIC);
1039 if (ret)
1040 goto err_alloc_rx_sg;
1041
1042 ret = sg_alloc_table(&pl022->sgt_tx, pages, GFP_ATOMIC);
1043 if (ret)
1044 goto err_alloc_tx_sg;
1045
1046 /* Fill in the scatterlists for the RX+TX buffers */
1047 setup_dma_scatter(pl022, pl022->rx,
1048 pl022->cur_transfer->len, &pl022->sgt_rx);
1049 setup_dma_scatter(pl022, pl022->tx,
1050 pl022->cur_transfer->len, &pl022->sgt_tx);
1051
1052 /* Map DMA buffers */
1053 rx_sglen = dma_map_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
1054 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
1055 if (!rx_sglen)
1056 goto err_rx_sgmap;
1057
1058 tx_sglen = dma_map_sg(txchan->device->dev, pl022->sgt_tx.sgl,
1059 pl022->sgt_tx.nents, DMA_TO_DEVICE);
1060 if (!tx_sglen)
1061 goto err_tx_sgmap;
1062
1063 /* Send both scatterlists */
1064 rxdesc = dmaengine_prep_slave_sg(rxchan,
1065 pl022->sgt_rx.sgl,
1066 rx_sglen,
1067 DMA_DEV_TO_MEM,
1068 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1069 if (!rxdesc)
1070 goto err_rxdesc;
1071
1072 txdesc = dmaengine_prep_slave_sg(txchan,
1073 pl022->sgt_tx.sgl,
1074 tx_sglen,
1075 DMA_MEM_TO_DEV,
1076 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1077 if (!txdesc)
1078 goto err_txdesc;
1079
1080 /* Put the callback on the RX transfer only, that should finish last */
1081 rxdesc->callback = dma_callback;
1082 rxdesc->callback_param = pl022;
1083
1084 /* Submit and fire RX and TX with TX last so we're ready to read! */
1085 dmaengine_submit(rxdesc);
1086 dmaengine_submit(txdesc);
1087 dma_async_issue_pending(rxchan);
1088 dma_async_issue_pending(txchan);
1089 pl022->dma_running = true;
1090
1091 return 0;
1092
1093err_txdesc:
1094 dmaengine_terminate_all(txchan);
1095err_rxdesc:
1096 dmaengine_terminate_all(rxchan);
1097 dma_unmap_sg(txchan->device->dev, pl022->sgt_tx.sgl,
1098 pl022->sgt_tx.nents, DMA_TO_DEVICE);
1099err_tx_sgmap:
1100 dma_unmap_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
1101 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
1102err_rx_sgmap:
1103 sg_free_table(&pl022->sgt_tx);
1104err_alloc_tx_sg:
1105 sg_free_table(&pl022->sgt_rx);
1106err_alloc_rx_sg:
1107 return -ENOMEM;
1108}
1109
1110static int pl022_dma_probe(struct pl022 *pl022)
1111{
1112 dma_cap_mask_t mask;
1113
1114 /* Try to acquire a generic DMA engine slave channel */
1115 dma_cap_zero(mask);
1116 dma_cap_set(DMA_SLAVE, mask);
1117 /*
1118 * We need both RX and TX channels to do DMA, else do none
1119 * of them.
1120 */
1121 pl022->dma_rx_channel = dma_request_channel(mask,
1122 pl022->master_info->dma_filter,
1123 pl022->master_info->dma_rx_param);
1124 if (!pl022->dma_rx_channel) {
1125 dev_dbg(&pl022->adev->dev, "no RX DMA channel!\n");
1126 goto err_no_rxchan;
1127 }
1128
1129 pl022->dma_tx_channel = dma_request_channel(mask,
1130 pl022->master_info->dma_filter,
1131 pl022->master_info->dma_tx_param);
1132 if (!pl022->dma_tx_channel) {
1133 dev_dbg(&pl022->adev->dev, "no TX DMA channel!\n");
1134 goto err_no_txchan;
1135 }
1136
1137 pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
1138 if (!pl022->dummypage)
1139 goto err_no_dummypage;
1140
1141 dev_info(&pl022->adev->dev, "setup for DMA on RX %s, TX %s\n",
1142 dma_chan_name(pl022->dma_rx_channel),
1143 dma_chan_name(pl022->dma_tx_channel));
1144
1145 return 0;
1146
1147err_no_dummypage:
1148 dma_release_channel(pl022->dma_tx_channel);
1149err_no_txchan:
1150 dma_release_channel(pl022->dma_rx_channel);
1151 pl022->dma_rx_channel = NULL;
1152err_no_rxchan:
1153 dev_err(&pl022->adev->dev,
1154 "Failed to work in dma mode, work without dma!\n");
1155 return -ENODEV;
1156}
1157
1158static int pl022_dma_autoprobe(struct pl022 *pl022)
1159{
1160 struct device *dev = &pl022->adev->dev;
1161 struct dma_chan *chan;
1162 int err;
1163
1164 /* automatically configure DMA channels from platform, normally using DT */
1165 chan = dma_request_chan(dev, "rx");
1166 if (IS_ERR(chan)) {
1167 err = PTR_ERR(chan);
1168 goto err_no_rxchan;
1169 }
1170
1171 pl022->dma_rx_channel = chan;
1172
1173 chan = dma_request_chan(dev, "tx");
1174 if (IS_ERR(chan)) {
1175 err = PTR_ERR(chan);
1176 goto err_no_txchan;
1177 }
1178
1179 pl022->dma_tx_channel = chan;
1180
1181 pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
1182 if (!pl022->dummypage) {
1183 err = -ENOMEM;
1184 goto err_no_dummypage;
1185 }
1186
1187 return 0;
1188
1189err_no_dummypage:
1190 dma_release_channel(pl022->dma_tx_channel);
1191 pl022->dma_tx_channel = NULL;
1192err_no_txchan:
1193 dma_release_channel(pl022->dma_rx_channel);
1194 pl022->dma_rx_channel = NULL;
1195err_no_rxchan:
1196 return err;
1197}
1198
1199static void terminate_dma(struct pl022 *pl022)
1200{
1201 struct dma_chan *rxchan = pl022->dma_rx_channel;
1202 struct dma_chan *txchan = pl022->dma_tx_channel;
1203
1204 dmaengine_terminate_all(rxchan);
1205 dmaengine_terminate_all(txchan);
1206 unmap_free_dma_scatter(pl022);
1207 pl022->dma_running = false;
1208}
1209
1210static void pl022_dma_remove(struct pl022 *pl022)
1211{
1212 if (pl022->dma_running)
1213 terminate_dma(pl022);
1214 if (pl022->dma_tx_channel)
1215 dma_release_channel(pl022->dma_tx_channel);
1216 if (pl022->dma_rx_channel)
1217 dma_release_channel(pl022->dma_rx_channel);
1218 kfree(pl022->dummypage);
1219}
1220
1221#else
1222static inline int configure_dma(struct pl022 *pl022)
1223{
1224 return -ENODEV;
1225}
1226
1227static inline int pl022_dma_autoprobe(struct pl022 *pl022)
1228{
1229 return 0;
1230}
1231
1232static inline int pl022_dma_probe(struct pl022 *pl022)
1233{
1234 return 0;
1235}
1236
1237static inline void pl022_dma_remove(struct pl022 *pl022)
1238{
1239}
1240#endif
1241
1242/**
1243 * pl022_interrupt_handler - Interrupt handler for SSP controller
1244 * @irq: IRQ number
1245 * @dev_id: Local device data
1246 *
1247 * This function handles interrupts generated for an interrupt based transfer.
1248 * If a receive overrun (ROR) interrupt is there then we disable SSP, flag the
1249 * current message's state as STATE_ERROR and schedule the tasklet
1250 * pump_transfers which will do the postprocessing of the current message by
1251 * calling giveback(). Otherwise it reads data from RX FIFO till there is no
1252 * more data, and writes data in TX FIFO till it is not full. If we complete
1253 * the transfer we move to the next transfer and schedule the tasklet.
1254 */
1255static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id)
1256{
1257 struct pl022 *pl022 = dev_id;
1258 struct spi_message *msg = pl022->cur_msg;
1259 u16 irq_status = 0;
1260
1261 if (unlikely(!msg)) {
1262 dev_err(&pl022->adev->dev,
1263 "bad message state in interrupt handler");
1264 /* Never fail */
1265 return IRQ_HANDLED;
1266 }
1267
1268 /* Read the Interrupt Status Register */
1269 irq_status = readw(SSP_MIS(pl022->virtbase));
1270
1271 if (unlikely(!irq_status))
1272 return IRQ_NONE;
1273
1274 /*
1275 * This handles the FIFO interrupts, the timeout
1276 * interrupts are flatly ignored, they cannot be
1277 * trusted.
1278 */
1279 if (unlikely(irq_status & SSP_MIS_MASK_RORMIS)) {
1280 /*
1281 * Overrun interrupt - bail out since our Data has been
1282 * corrupted
1283 */
1284 dev_err(&pl022->adev->dev, "FIFO overrun\n");
1285 if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RFF)
1286 dev_err(&pl022->adev->dev,
1287 "RXFIFO is full\n");
1288
1289 /*
1290 * Disable and clear interrupts, disable SSP,
1291 * mark message with bad status so it can be
1292 * retried.
1293 */
1294 writew(DISABLE_ALL_INTERRUPTS,
1295 SSP_IMSC(pl022->virtbase));
1296 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1297 writew((readw(SSP_CR1(pl022->virtbase)) &
1298 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1299 msg->state = STATE_ERROR;
1300
1301 /* Schedule message queue handler */
1302 tasklet_schedule(&pl022->pump_transfers);
1303 return IRQ_HANDLED;
1304 }
1305
1306 readwriter(pl022);
1307
1308 if (pl022->tx == pl022->tx_end) {
1309 /* Disable Transmit interrupt, enable receive interrupt */
1310 writew((readw(SSP_IMSC(pl022->virtbase)) &
1311 ~SSP_IMSC_MASK_TXIM) | SSP_IMSC_MASK_RXIM,
1312 SSP_IMSC(pl022->virtbase));
1313 }
1314
1315 /*
1316 * Since all transactions must write as much as shall be read,
1317 * we can conclude the entire transaction once RX is complete.
1318 * At this point, all TX will always be finished.
1319 */
1320 if (pl022->rx >= pl022->rx_end) {
1321 writew(DISABLE_ALL_INTERRUPTS,
1322 SSP_IMSC(pl022->virtbase));
1323 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1324 if (unlikely(pl022->rx > pl022->rx_end)) {
1325 dev_warn(&pl022->adev->dev, "read %u surplus "
1326 "bytes (did you request an odd "
1327 "number of bytes on a 16bit bus?)\n",
1328 (u32) (pl022->rx - pl022->rx_end));
1329 }
1330 /* Update total bytes transferred */
1331 msg->actual_length += pl022->cur_transfer->len;
1332 /* Move to next transfer */
1333 msg->state = next_transfer(pl022);
1334 if (msg->state != STATE_DONE && pl022->cur_transfer->cs_change)
1335 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
1336 tasklet_schedule(&pl022->pump_transfers);
1337 return IRQ_HANDLED;
1338 }
1339
1340 return IRQ_HANDLED;
1341}
1342
1343/*
1344 * This sets up the pointers to memory for the next message to
1345 * send out on the SPI bus.
1346 */
1347static int set_up_next_transfer(struct pl022 *pl022,
1348 struct spi_transfer *transfer)
1349{
1350 int residue;
1351
1352 /* Sanity check the message for this bus width */
1353 residue = pl022->cur_transfer->len % pl022->cur_chip->n_bytes;
1354 if (unlikely(residue != 0)) {
1355 dev_err(&pl022->adev->dev,
1356 "message of %u bytes to transmit but the current "
1357 "chip bus has a data width of %u bytes!\n",
1358 pl022->cur_transfer->len,
1359 pl022->cur_chip->n_bytes);
1360 dev_err(&pl022->adev->dev, "skipping this message\n");
1361 return -EIO;
1362 }
1363 pl022->tx = (void *)transfer->tx_buf;
1364 pl022->tx_end = pl022->tx + pl022->cur_transfer->len;
1365 pl022->rx = (void *)transfer->rx_buf;
1366 pl022->rx_end = pl022->rx + pl022->cur_transfer->len;
1367 pl022->write =
1368 pl022->tx ? pl022->cur_chip->write : WRITING_NULL;
1369 pl022->read = pl022->rx ? pl022->cur_chip->read : READING_NULL;
1370 return 0;
1371}
1372
1373/**
1374 * pump_transfers - Tasklet function which schedules next transfer
1375 * when running in interrupt or DMA transfer mode.
1376 * @data: SSP driver private data structure
1377 *
1378 */
1379static void pump_transfers(unsigned long data)
1380{
1381 struct pl022 *pl022 = (struct pl022 *) data;
1382 struct spi_message *message = NULL;
1383 struct spi_transfer *transfer = NULL;
1384 struct spi_transfer *previous = NULL;
1385
1386 /* Get current state information */
1387 message = pl022->cur_msg;
1388 transfer = pl022->cur_transfer;
1389
1390 /* Handle for abort */
1391 if (message->state == STATE_ERROR) {
1392 message->status = -EIO;
1393 giveback(pl022);
1394 return;
1395 }
1396
1397 /* Handle end of message */
1398 if (message->state == STATE_DONE) {
1399 message->status = 0;
1400 giveback(pl022);
1401 return;
1402 }
1403
1404 /* Delay if requested at end of transfer before CS change */
1405 if (message->state == STATE_RUNNING) {
1406 previous = list_entry(transfer->transfer_list.prev,
1407 struct spi_transfer,
1408 transfer_list);
1409 /*
1410 * FIXME: This runs in interrupt context.
1411 * Is this really smart?
1412 */
1413 spi_transfer_delay_exec(previous);
1414
1415 /* Reselect chip select only if cs_change was requested */
1416 if (previous->cs_change)
1417 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1418 } else {
1419 /* STATE_START */
1420 message->state = STATE_RUNNING;
1421 }
1422
1423 if (set_up_next_transfer(pl022, transfer)) {
1424 message->state = STATE_ERROR;
1425 message->status = -EIO;
1426 giveback(pl022);
1427 return;
1428 }
1429 /* Flush the FIFOs and let's go! */
1430 flush(pl022);
1431
1432 if (pl022->cur_chip->enable_dma) {
1433 if (configure_dma(pl022)) {
1434 dev_dbg(&pl022->adev->dev,
1435 "configuration of DMA failed, fall back to interrupt mode\n");
1436 goto err_config_dma;
1437 }
1438 return;
1439 }
1440
1441err_config_dma:
1442 /* enable all interrupts except RX */
1443 writew(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM, SSP_IMSC(pl022->virtbase));
1444}
1445
1446static void do_interrupt_dma_transfer(struct pl022 *pl022)
1447{
1448 /*
1449 * Default is to enable all interrupts except RX -
1450 * this will be enabled once TX is complete
1451 */
1452 u32 irqflags = (u32)(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM);
1453
1454 /* Enable target chip, if not already active */
1455 if (!pl022->next_msg_cs_active)
1456 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1457
1458 if (set_up_next_transfer(pl022, pl022->cur_transfer)) {
1459 /* Error path */
1460 pl022->cur_msg->state = STATE_ERROR;
1461 pl022->cur_msg->status = -EIO;
1462 giveback(pl022);
1463 return;
1464 }
1465 /* If we're using DMA, set up DMA here */
1466 if (pl022->cur_chip->enable_dma) {
1467 /* Configure DMA transfer */
1468 if (configure_dma(pl022)) {
1469 dev_dbg(&pl022->adev->dev,
1470 "configuration of DMA failed, fall back to interrupt mode\n");
1471 goto err_config_dma;
1472 }
1473 /* Disable interrupts in DMA mode, IRQ from DMA controller */
1474 irqflags = DISABLE_ALL_INTERRUPTS;
1475 }
1476err_config_dma:
1477 /* Enable SSP, turn on interrupts */
1478 writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1479 SSP_CR1(pl022->virtbase));
1480 writew(irqflags, SSP_IMSC(pl022->virtbase));
1481}
1482
1483static void print_current_status(struct pl022 *pl022)
1484{
1485 u32 read_cr0;
1486 u16 read_cr1, read_dmacr, read_sr;
1487
1488 if (pl022->vendor->extended_cr)
1489 read_cr0 = readl(SSP_CR0(pl022->virtbase));
1490 else
1491 read_cr0 = readw(SSP_CR0(pl022->virtbase));
1492 read_cr1 = readw(SSP_CR1(pl022->virtbase));
1493 read_dmacr = readw(SSP_DMACR(pl022->virtbase));
1494 read_sr = readw(SSP_SR(pl022->virtbase));
1495
1496 dev_warn(&pl022->adev->dev, "spi-pl022 CR0: %x\n", read_cr0);
1497 dev_warn(&pl022->adev->dev, "spi-pl022 CR1: %x\n", read_cr1);
1498 dev_warn(&pl022->adev->dev, "spi-pl022 DMACR: %x\n", read_dmacr);
1499 dev_warn(&pl022->adev->dev, "spi-pl022 SR: %x\n", read_sr);
1500 dev_warn(&pl022->adev->dev,
1501 "spi-pl022 exp_fifo_level/fifodepth: %u/%d\n",
1502 pl022->exp_fifo_level,
1503 pl022->vendor->fifodepth);
1504
1505}
1506
1507static void do_polling_transfer(struct pl022 *pl022)
1508{
1509 struct spi_message *message = NULL;
1510 struct spi_transfer *transfer = NULL;
1511 struct spi_transfer *previous = NULL;
1512 unsigned long time, timeout;
1513
1514 message = pl022->cur_msg;
1515
1516 while (message->state != STATE_DONE) {
1517 /* Handle for abort */
1518 if (message->state == STATE_ERROR)
1519 break;
1520 transfer = pl022->cur_transfer;
1521
1522 /* Delay if requested at end of transfer */
1523 if (message->state == STATE_RUNNING) {
1524 previous =
1525 list_entry(transfer->transfer_list.prev,
1526 struct spi_transfer, transfer_list);
1527 spi_transfer_delay_exec(previous);
1528 if (previous->cs_change)
1529 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1530 } else {
1531 /* STATE_START */
1532 message->state = STATE_RUNNING;
1533 if (!pl022->next_msg_cs_active)
1534 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1535 }
1536
1537 /* Configuration Changing Per Transfer */
1538 if (set_up_next_transfer(pl022, transfer)) {
1539 /* Error path */
1540 message->state = STATE_ERROR;
1541 break;
1542 }
1543 /* Flush FIFOs and enable SSP */
1544 flush(pl022);
1545 writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1546 SSP_CR1(pl022->virtbase));
1547
1548 dev_dbg(&pl022->adev->dev, "polling transfer ongoing ...\n");
1549
1550 timeout = jiffies + msecs_to_jiffies(SPI_POLLING_TIMEOUT);
1551 while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end) {
1552 time = jiffies;
1553 readwriter(pl022);
1554 if (time_after(time, timeout)) {
1555 dev_warn(&pl022->adev->dev,
1556 "%s: timeout!\n", __func__);
1557 message->state = STATE_TIMEOUT;
1558 print_current_status(pl022);
1559 goto out;
1560 }
1561 cpu_relax();
1562 }
1563
1564 /* Update total byte transferred */
1565 message->actual_length += pl022->cur_transfer->len;
1566 /* Move to next transfer */
1567 message->state = next_transfer(pl022);
1568 if (message->state != STATE_DONE
1569 && pl022->cur_transfer->cs_change)
1570 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
1571 }
1572out:
1573 /* Handle end of message */
1574 if (message->state == STATE_DONE)
1575 message->status = 0;
1576 else if (message->state == STATE_TIMEOUT)
1577 message->status = -EAGAIN;
1578 else
1579 message->status = -EIO;
1580
1581 giveback(pl022);
1582 return;
1583}
1584
1585static int pl022_transfer_one_message(struct spi_master *master,
1586 struct spi_message *msg)
1587{
1588 struct pl022 *pl022 = spi_master_get_devdata(master);
1589
1590 /* Initial message state */
1591 pl022->cur_msg = msg;
1592 msg->state = STATE_START;
1593
1594 pl022->cur_transfer = list_entry(msg->transfers.next,
1595 struct spi_transfer, transfer_list);
1596
1597 /* Setup the SPI using the per chip configuration */
1598 pl022->cur_chip = spi_get_ctldata(msg->spi);
1599 pl022->cur_cs = pl022->chipselects[msg->spi->chip_select];
1600
1601 restore_state(pl022);
1602 flush(pl022);
1603
1604 if (pl022->cur_chip->xfer_type == POLLING_TRANSFER)
1605 do_polling_transfer(pl022);
1606 else
1607 do_interrupt_dma_transfer(pl022);
1608
1609 return 0;
1610}
1611
1612static int pl022_unprepare_transfer_hardware(struct spi_master *master)
1613{
1614 struct pl022 *pl022 = spi_master_get_devdata(master);
1615
1616 /* nothing more to do - disable spi/ssp and power off */
1617 writew((readw(SSP_CR1(pl022->virtbase)) &
1618 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1619
1620 return 0;
1621}
1622
1623static int verify_controller_parameters(struct pl022 *pl022,
1624 struct pl022_config_chip const *chip_info)
1625{
1626 if ((chip_info->iface < SSP_INTERFACE_MOTOROLA_SPI)
1627 || (chip_info->iface > SSP_INTERFACE_UNIDIRECTIONAL)) {
1628 dev_err(&pl022->adev->dev,
1629 "interface is configured incorrectly\n");
1630 return -EINVAL;
1631 }
1632 if ((chip_info->iface == SSP_INTERFACE_UNIDIRECTIONAL) &&
1633 (!pl022->vendor->unidir)) {
1634 dev_err(&pl022->adev->dev,
1635 "unidirectional mode not supported in this "
1636 "hardware version\n");
1637 return -EINVAL;
1638 }
1639 if ((chip_info->hierarchy != SSP_MASTER)
1640 && (chip_info->hierarchy != SSP_SLAVE)) {
1641 dev_err(&pl022->adev->dev,
1642 "hierarchy is configured incorrectly\n");
1643 return -EINVAL;
1644 }
1645 if ((chip_info->com_mode != INTERRUPT_TRANSFER)
1646 && (chip_info->com_mode != DMA_TRANSFER)
1647 && (chip_info->com_mode != POLLING_TRANSFER)) {
1648 dev_err(&pl022->adev->dev,
1649 "Communication mode is configured incorrectly\n");
1650 return -EINVAL;
1651 }
1652 switch (chip_info->rx_lev_trig) {
1653 case SSP_RX_1_OR_MORE_ELEM:
1654 case SSP_RX_4_OR_MORE_ELEM:
1655 case SSP_RX_8_OR_MORE_ELEM:
1656 /* These are always OK, all variants can handle this */
1657 break;
1658 case SSP_RX_16_OR_MORE_ELEM:
1659 if (pl022->vendor->fifodepth < 16) {
1660 dev_err(&pl022->adev->dev,
1661 "RX FIFO Trigger Level is configured incorrectly\n");
1662 return -EINVAL;
1663 }
1664 break;
1665 case SSP_RX_32_OR_MORE_ELEM:
1666 if (pl022->vendor->fifodepth < 32) {
1667 dev_err(&pl022->adev->dev,
1668 "RX FIFO Trigger Level is configured incorrectly\n");
1669 return -EINVAL;
1670 }
1671 break;
1672 default:
1673 dev_err(&pl022->adev->dev,
1674 "RX FIFO Trigger Level is configured incorrectly\n");
1675 return -EINVAL;
1676 }
1677 switch (chip_info->tx_lev_trig) {
1678 case SSP_TX_1_OR_MORE_EMPTY_LOC:
1679 case SSP_TX_4_OR_MORE_EMPTY_LOC:
1680 case SSP_TX_8_OR_MORE_EMPTY_LOC:
1681 /* These are always OK, all variants can handle this */
1682 break;
1683 case SSP_TX_16_OR_MORE_EMPTY_LOC:
1684 if (pl022->vendor->fifodepth < 16) {
1685 dev_err(&pl022->adev->dev,
1686 "TX FIFO Trigger Level is configured incorrectly\n");
1687 return -EINVAL;
1688 }
1689 break;
1690 case SSP_TX_32_OR_MORE_EMPTY_LOC:
1691 if (pl022->vendor->fifodepth < 32) {
1692 dev_err(&pl022->adev->dev,
1693 "TX FIFO Trigger Level is configured incorrectly\n");
1694 return -EINVAL;
1695 }
1696 break;
1697 default:
1698 dev_err(&pl022->adev->dev,
1699 "TX FIFO Trigger Level is configured incorrectly\n");
1700 return -EINVAL;
1701 }
1702 if (chip_info->iface == SSP_INTERFACE_NATIONAL_MICROWIRE) {
1703 if ((chip_info->ctrl_len < SSP_BITS_4)
1704 || (chip_info->ctrl_len > SSP_BITS_32)) {
1705 dev_err(&pl022->adev->dev,
1706 "CTRL LEN is configured incorrectly\n");
1707 return -EINVAL;
1708 }
1709 if ((chip_info->wait_state != SSP_MWIRE_WAIT_ZERO)
1710 && (chip_info->wait_state != SSP_MWIRE_WAIT_ONE)) {
1711 dev_err(&pl022->adev->dev,
1712 "Wait State is configured incorrectly\n");
1713 return -EINVAL;
1714 }
1715 /* Half duplex is only available in the ST Micro version */
1716 if (pl022->vendor->extended_cr) {
1717 if ((chip_info->duplex !=
1718 SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
1719 && (chip_info->duplex !=
1720 SSP_MICROWIRE_CHANNEL_HALF_DUPLEX)) {
1721 dev_err(&pl022->adev->dev,
1722 "Microwire duplex mode is configured incorrectly\n");
1723 return -EINVAL;
1724 }
1725 } else {
1726 if (chip_info->duplex != SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
1727 dev_err(&pl022->adev->dev,
1728 "Microwire half duplex mode requested,"
1729 " but this is only available in the"
1730 " ST version of PL022\n");
1731 return -EINVAL;
1732 }
1733 }
1734 return 0;
1735}
1736
1737static inline u32 spi_rate(u32 rate, u16 cpsdvsr, u16 scr)
1738{
1739 return rate / (cpsdvsr * (1 + scr));
1740}
1741
1742static int calculate_effective_freq(struct pl022 *pl022, int freq, struct
1743 ssp_clock_params * clk_freq)
1744{
1745 /* Lets calculate the frequency parameters */
1746 u16 cpsdvsr = CPSDVR_MIN, scr = SCR_MIN;
1747 u32 rate, max_tclk, min_tclk, best_freq = 0, best_cpsdvsr = 0,
1748 best_scr = 0, tmp, found = 0;
1749
1750 rate = clk_get_rate(pl022->clk);
1751 /* cpsdvscr = 2 & scr 0 */
1752 max_tclk = spi_rate(rate, CPSDVR_MIN, SCR_MIN);
1753 /* cpsdvsr = 254 & scr = 255 */
1754 min_tclk = spi_rate(rate, CPSDVR_MAX, SCR_MAX);
1755
1756 if (freq > max_tclk)
1757 dev_warn(&pl022->adev->dev,
1758 "Max speed that can be programmed is %d Hz, you requested %d\n",
1759 max_tclk, freq);
1760
1761 if (freq < min_tclk) {
1762 dev_err(&pl022->adev->dev,
1763 "Requested frequency: %d Hz is less than minimum possible %d Hz\n",
1764 freq, min_tclk);
1765 return -EINVAL;
1766 }
1767
1768 /*
1769 * best_freq will give closest possible available rate (<= requested
1770 * freq) for all values of scr & cpsdvsr.
1771 */
1772 while ((cpsdvsr <= CPSDVR_MAX) && !found) {
1773 while (scr <= SCR_MAX) {
1774 tmp = spi_rate(rate, cpsdvsr, scr);
1775
1776 if (tmp > freq) {
1777 /* we need lower freq */
1778 scr++;
1779 continue;
1780 }
1781
1782 /*
1783 * If found exact value, mark found and break.
1784 * If found more closer value, update and break.
1785 */
1786 if (tmp > best_freq) {
1787 best_freq = tmp;
1788 best_cpsdvsr = cpsdvsr;
1789 best_scr = scr;
1790
1791 if (tmp == freq)
1792 found = 1;
1793 }
1794 /*
1795 * increased scr will give lower rates, which are not
1796 * required
1797 */
1798 break;
1799 }
1800 cpsdvsr += 2;
1801 scr = SCR_MIN;
1802 }
1803
1804 WARN(!best_freq, "pl022: Matching cpsdvsr and scr not found for %d Hz rate \n",
1805 freq);
1806
1807 clk_freq->cpsdvsr = (u8) (best_cpsdvsr & 0xFF);
1808 clk_freq->scr = (u8) (best_scr & 0xFF);
1809 dev_dbg(&pl022->adev->dev,
1810 "SSP Target Frequency is: %u, Effective Frequency is %u\n",
1811 freq, best_freq);
1812 dev_dbg(&pl022->adev->dev, "SSP cpsdvsr = %d, scr = %d\n",
1813 clk_freq->cpsdvsr, clk_freq->scr);
1814
1815 return 0;
1816}
1817
1818/*
1819 * A piece of default chip info unless the platform
1820 * supplies it.
1821 */
1822static const struct pl022_config_chip pl022_default_chip_info = {
1823 .com_mode = POLLING_TRANSFER,
1824 .iface = SSP_INTERFACE_MOTOROLA_SPI,
1825 .hierarchy = SSP_SLAVE,
1826 .slave_tx_disable = DO_NOT_DRIVE_TX,
1827 .rx_lev_trig = SSP_RX_1_OR_MORE_ELEM,
1828 .tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC,
1829 .ctrl_len = SSP_BITS_8,
1830 .wait_state = SSP_MWIRE_WAIT_ZERO,
1831 .duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX,
1832 .cs_control = null_cs_control,
1833};
1834
1835/**
1836 * pl022_setup - setup function registered to SPI master framework
1837 * @spi: spi device which is requesting setup
1838 *
1839 * This function is registered to the SPI framework for this SPI master
1840 * controller. If it is the first time when setup is called by this device,
1841 * this function will initialize the runtime state for this chip and save
1842 * the same in the device structure. Else it will update the runtime info
1843 * with the updated chip info. Nothing is really being written to the
1844 * controller hardware here, that is not done until the actual transfer
1845 * commence.
1846 */
1847static int pl022_setup(struct spi_device *spi)
1848{
1849 struct pl022_config_chip const *chip_info;
1850 struct pl022_config_chip chip_info_dt;
1851 struct chip_data *chip;
1852 struct ssp_clock_params clk_freq = { .cpsdvsr = 0, .scr = 0};
1853 int status = 0;
1854 struct pl022 *pl022 = spi_master_get_devdata(spi->master);
1855 unsigned int bits = spi->bits_per_word;
1856 u32 tmp;
1857 struct device_node *np = spi->dev.of_node;
1858
1859 if (!spi->max_speed_hz)
1860 return -EINVAL;
1861
1862 /* Get controller_state if one is supplied */
1863 chip = spi_get_ctldata(spi);
1864
1865 if (chip == NULL) {
1866 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
1867 if (!chip)
1868 return -ENOMEM;
1869 dev_dbg(&spi->dev,
1870 "allocated memory for controller's runtime state\n");
1871 }
1872
1873 /* Get controller data if one is supplied */
1874 chip_info = spi->controller_data;
1875
1876 if (chip_info == NULL) {
1877 if (np) {
1878 chip_info_dt = pl022_default_chip_info;
1879
1880 chip_info_dt.hierarchy = SSP_MASTER;
1881 of_property_read_u32(np, "pl022,interface",
1882 &chip_info_dt.iface);
1883 of_property_read_u32(np, "pl022,com-mode",
1884 &chip_info_dt.com_mode);
1885 of_property_read_u32(np, "pl022,rx-level-trig",
1886 &chip_info_dt.rx_lev_trig);
1887 of_property_read_u32(np, "pl022,tx-level-trig",
1888 &chip_info_dt.tx_lev_trig);
1889 of_property_read_u32(np, "pl022,ctrl-len",
1890 &chip_info_dt.ctrl_len);
1891 of_property_read_u32(np, "pl022,wait-state",
1892 &chip_info_dt.wait_state);
1893 of_property_read_u32(np, "pl022,duplex",
1894 &chip_info_dt.duplex);
1895
1896 chip_info = &chip_info_dt;
1897 } else {
1898 chip_info = &pl022_default_chip_info;
1899 /* spi_board_info.controller_data not is supplied */
1900 dev_dbg(&spi->dev,
1901 "using default controller_data settings\n");
1902 }
1903 } else
1904 dev_dbg(&spi->dev,
1905 "using user supplied controller_data settings\n");
1906
1907 /*
1908 * We can override with custom divisors, else we use the board
1909 * frequency setting
1910 */
1911 if ((0 == chip_info->clk_freq.cpsdvsr)
1912 && (0 == chip_info->clk_freq.scr)) {
1913 status = calculate_effective_freq(pl022,
1914 spi->max_speed_hz,
1915 &clk_freq);
1916 if (status < 0)
1917 goto err_config_params;
1918 } else {
1919 memcpy(&clk_freq, &chip_info->clk_freq, sizeof(clk_freq));
1920 if ((clk_freq.cpsdvsr % 2) != 0)
1921 clk_freq.cpsdvsr =
1922 clk_freq.cpsdvsr - 1;
1923 }
1924 if ((clk_freq.cpsdvsr < CPSDVR_MIN)
1925 || (clk_freq.cpsdvsr > CPSDVR_MAX)) {
1926 status = -EINVAL;
1927 dev_err(&spi->dev,
1928 "cpsdvsr is configured incorrectly\n");
1929 goto err_config_params;
1930 }
1931
1932 status = verify_controller_parameters(pl022, chip_info);
1933 if (status) {
1934 dev_err(&spi->dev, "controller data is incorrect");
1935 goto err_config_params;
1936 }
1937
1938 pl022->rx_lev_trig = chip_info->rx_lev_trig;
1939 pl022->tx_lev_trig = chip_info->tx_lev_trig;
1940
1941 /* Now set controller state based on controller data */
1942 chip->xfer_type = chip_info->com_mode;
1943 if (!chip_info->cs_control) {
1944 chip->cs_control = null_cs_control;
1945 if (!gpio_is_valid(pl022->chipselects[spi->chip_select]))
1946 dev_warn(&spi->dev,
1947 "invalid chip select\n");
1948 } else
1949 chip->cs_control = chip_info->cs_control;
1950
1951 /* Check bits per word with vendor specific range */
1952 if ((bits <= 3) || (bits > pl022->vendor->max_bpw)) {
1953 status = -ENOTSUPP;
1954 dev_err(&spi->dev, "illegal data size for this controller!\n");
1955 dev_err(&spi->dev, "This controller can only handle 4 <= n <= %d bit words\n",
1956 pl022->vendor->max_bpw);
1957 goto err_config_params;
1958 } else if (bits <= 8) {
1959 dev_dbg(&spi->dev, "4 <= n <=8 bits per word\n");
1960 chip->n_bytes = 1;
1961 chip->read = READING_U8;
1962 chip->write = WRITING_U8;
1963 } else if (bits <= 16) {
1964 dev_dbg(&spi->dev, "9 <= n <= 16 bits per word\n");
1965 chip->n_bytes = 2;
1966 chip->read = READING_U16;
1967 chip->write = WRITING_U16;
1968 } else {
1969 dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n");
1970 chip->n_bytes = 4;
1971 chip->read = READING_U32;
1972 chip->write = WRITING_U32;
1973 }
1974
1975 /* Now Initialize all register settings required for this chip */
1976 chip->cr0 = 0;
1977 chip->cr1 = 0;
1978 chip->dmacr = 0;
1979 chip->cpsr = 0;
1980 if ((chip_info->com_mode == DMA_TRANSFER)
1981 && ((pl022->master_info)->enable_dma)) {
1982 chip->enable_dma = true;
1983 dev_dbg(&spi->dev, "DMA mode set in controller state\n");
1984 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
1985 SSP_DMACR_MASK_RXDMAE, 0);
1986 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
1987 SSP_DMACR_MASK_TXDMAE, 1);
1988 } else {
1989 chip->enable_dma = false;
1990 dev_dbg(&spi->dev, "DMA mode NOT set in controller state\n");
1991 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
1992 SSP_DMACR_MASK_RXDMAE, 0);
1993 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
1994 SSP_DMACR_MASK_TXDMAE, 1);
1995 }
1996
1997 chip->cpsr = clk_freq.cpsdvsr;
1998
1999 /* Special setup for the ST micro extended control registers */
2000 if (pl022->vendor->extended_cr) {
2001 u32 etx;
2002
2003 if (pl022->vendor->pl023) {
2004 /* These bits are only in the PL023 */
2005 SSP_WRITE_BITS(chip->cr1, chip_info->clkdelay,
2006 SSP_CR1_MASK_FBCLKDEL_ST, 13);
2007 } else {
2008 /* These bits are in the PL022 but not PL023 */
2009 SSP_WRITE_BITS(chip->cr0, chip_info->duplex,
2010 SSP_CR0_MASK_HALFDUP_ST, 5);
2011 SSP_WRITE_BITS(chip->cr0, chip_info->ctrl_len,
2012 SSP_CR0_MASK_CSS_ST, 16);
2013 SSP_WRITE_BITS(chip->cr0, chip_info->iface,
2014 SSP_CR0_MASK_FRF_ST, 21);
2015 SSP_WRITE_BITS(chip->cr1, chip_info->wait_state,
2016 SSP_CR1_MASK_MWAIT_ST, 6);
2017 }
2018 SSP_WRITE_BITS(chip->cr0, bits - 1,
2019 SSP_CR0_MASK_DSS_ST, 0);
2020
2021 if (spi->mode & SPI_LSB_FIRST) {
2022 tmp = SSP_RX_LSB;
2023 etx = SSP_TX_LSB;
2024 } else {
2025 tmp = SSP_RX_MSB;
2026 etx = SSP_TX_MSB;
2027 }
2028 SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_RENDN_ST, 4);
2029 SSP_WRITE_BITS(chip->cr1, etx, SSP_CR1_MASK_TENDN_ST, 5);
2030 SSP_WRITE_BITS(chip->cr1, chip_info->rx_lev_trig,
2031 SSP_CR1_MASK_RXIFLSEL_ST, 7);
2032 SSP_WRITE_BITS(chip->cr1, chip_info->tx_lev_trig,
2033 SSP_CR1_MASK_TXIFLSEL_ST, 10);
2034 } else {
2035 SSP_WRITE_BITS(chip->cr0, bits - 1,
2036 SSP_CR0_MASK_DSS, 0);
2037 SSP_WRITE_BITS(chip->cr0, chip_info->iface,
2038 SSP_CR0_MASK_FRF, 4);
2039 }
2040
2041 /* Stuff that is common for all versions */
2042 if (spi->mode & SPI_CPOL)
2043 tmp = SSP_CLK_POL_IDLE_HIGH;
2044 else
2045 tmp = SSP_CLK_POL_IDLE_LOW;
2046 SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPO, 6);
2047
2048 if (spi->mode & SPI_CPHA)
2049 tmp = SSP_CLK_SECOND_EDGE;
2050 else
2051 tmp = SSP_CLK_FIRST_EDGE;
2052 SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPH, 7);
2053
2054 SSP_WRITE_BITS(chip->cr0, clk_freq.scr, SSP_CR0_MASK_SCR, 8);
2055 /* Loopback is available on all versions except PL023 */
2056 if (pl022->vendor->loopback) {
2057 if (spi->mode & SPI_LOOP)
2058 tmp = LOOPBACK_ENABLED;
2059 else
2060 tmp = LOOPBACK_DISABLED;
2061 SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_LBM, 0);
2062 }
2063 SSP_WRITE_BITS(chip->cr1, SSP_DISABLED, SSP_CR1_MASK_SSE, 1);
2064 SSP_WRITE_BITS(chip->cr1, chip_info->hierarchy, SSP_CR1_MASK_MS, 2);
2065 SSP_WRITE_BITS(chip->cr1, chip_info->slave_tx_disable, SSP_CR1_MASK_SOD,
2066 3);
2067
2068 /* Save controller_state */
2069 spi_set_ctldata(spi, chip);
2070 return status;
2071 err_config_params:
2072 spi_set_ctldata(spi, NULL);
2073 kfree(chip);
2074 return status;
2075}
2076
2077/**
2078 * pl022_cleanup - cleanup function registered to SPI master framework
2079 * @spi: spi device which is requesting cleanup
2080 *
2081 * This function is registered to the SPI framework for this SPI master
2082 * controller. It will free the runtime state of chip.
2083 */
2084static void pl022_cleanup(struct spi_device *spi)
2085{
2086 struct chip_data *chip = spi_get_ctldata(spi);
2087
2088 spi_set_ctldata(spi, NULL);
2089 kfree(chip);
2090}
2091
2092static struct pl022_ssp_controller *
2093pl022_platform_data_dt_get(struct device *dev)
2094{
2095 struct device_node *np = dev->of_node;
2096 struct pl022_ssp_controller *pd;
2097 u32 tmp = 0;
2098
2099 if (!np) {
2100 dev_err(dev, "no dt node defined\n");
2101 return NULL;
2102 }
2103
2104 pd = devm_kzalloc(dev, sizeof(struct pl022_ssp_controller), GFP_KERNEL);
2105 if (!pd)
2106 return NULL;
2107
2108 pd->bus_id = -1;
2109 pd->enable_dma = 1;
2110 of_property_read_u32(np, "num-cs", &tmp);
2111 pd->num_chipselect = tmp;
2112 of_property_read_u32(np, "pl022,autosuspend-delay",
2113 &pd->autosuspend_delay);
2114 pd->rt = of_property_read_bool(np, "pl022,rt");
2115
2116 return pd;
2117}
2118
2119static int pl022_probe(struct amba_device *adev, const struct amba_id *id)
2120{
2121 struct device *dev = &adev->dev;
2122 struct pl022_ssp_controller *platform_info =
2123 dev_get_platdata(&adev->dev);
2124 struct spi_master *master;
2125 struct pl022 *pl022 = NULL; /*Data for this driver */
2126 struct device_node *np = adev->dev.of_node;
2127 int status = 0, i, num_cs;
2128
2129 dev_info(&adev->dev,
2130 "ARM PL022 driver, device ID: 0x%08x\n", adev->periphid);
2131 if (!platform_info && IS_ENABLED(CONFIG_OF))
2132 platform_info = pl022_platform_data_dt_get(dev);
2133
2134 if (!platform_info) {
2135 dev_err(dev, "probe: no platform data defined\n");
2136 return -ENODEV;
2137 }
2138
2139 if (platform_info->num_chipselect) {
2140 num_cs = platform_info->num_chipselect;
2141 } else {
2142 dev_err(dev, "probe: no chip select defined\n");
2143 return -ENODEV;
2144 }
2145
2146 /* Allocate master with space for data */
2147 master = spi_alloc_master(dev, sizeof(struct pl022));
2148 if (master == NULL) {
2149 dev_err(&adev->dev, "probe - cannot alloc SPI master\n");
2150 return -ENOMEM;
2151 }
2152
2153 pl022 = spi_master_get_devdata(master);
2154 pl022->master = master;
2155 pl022->master_info = platform_info;
2156 pl022->adev = adev;
2157 pl022->vendor = id->data;
2158 pl022->chipselects = devm_kcalloc(dev, num_cs, sizeof(int),
2159 GFP_KERNEL);
2160 if (!pl022->chipselects) {
2161 status = -ENOMEM;
2162 goto err_no_mem;
2163 }
2164
2165 /*
2166 * Bus Number Which has been Assigned to this SSP controller
2167 * on this board
2168 */
2169 master->bus_num = platform_info->bus_id;
2170 master->num_chipselect = num_cs;
2171 master->cleanup = pl022_cleanup;
2172 master->setup = pl022_setup;
2173 master->auto_runtime_pm = true;
2174 master->transfer_one_message = pl022_transfer_one_message;
2175 master->unprepare_transfer_hardware = pl022_unprepare_transfer_hardware;
2176 master->rt = platform_info->rt;
2177 master->dev.of_node = dev->of_node;
2178
2179 if (platform_info->num_chipselect && platform_info->chipselects) {
2180 for (i = 0; i < num_cs; i++)
2181 pl022->chipselects[i] = platform_info->chipselects[i];
2182 } else if (pl022->vendor->internal_cs_ctrl) {
2183 for (i = 0; i < num_cs; i++)
2184 pl022->chipselects[i] = i;
2185 } else if (IS_ENABLED(CONFIG_OF)) {
2186 for (i = 0; i < num_cs; i++) {
2187 int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
2188
2189 if (cs_gpio == -EPROBE_DEFER) {
2190 status = -EPROBE_DEFER;
2191 goto err_no_gpio;
2192 }
2193
2194 pl022->chipselects[i] = cs_gpio;
2195
2196 if (gpio_is_valid(cs_gpio)) {
2197 if (devm_gpio_request(dev, cs_gpio, "ssp-pl022"))
2198 dev_err(&adev->dev,
2199 "could not request %d gpio\n",
2200 cs_gpio);
2201 else if (gpio_direction_output(cs_gpio, 1))
2202 dev_err(&adev->dev,
2203 "could not set gpio %d as output\n",
2204 cs_gpio);
2205 }
2206 }
2207 }
2208
2209 /*
2210 * Supports mode 0-3, loopback, and active low CS. Transfers are
2211 * always MS bit first on the original pl022.
2212 */
2213 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
2214 if (pl022->vendor->extended_cr)
2215 master->mode_bits |= SPI_LSB_FIRST;
2216
2217 dev_dbg(&adev->dev, "BUSNO: %d\n", master->bus_num);
2218
2219 status = amba_request_regions(adev, NULL);
2220 if (status)
2221 goto err_no_ioregion;
2222
2223 pl022->phybase = adev->res.start;
2224 pl022->virtbase = devm_ioremap(dev, adev->res.start,
2225 resource_size(&adev->res));
2226 if (pl022->virtbase == NULL) {
2227 status = -ENOMEM;
2228 goto err_no_ioremap;
2229 }
2230 dev_info(&adev->dev, "mapped registers from %pa to %p\n",
2231 &adev->res.start, pl022->virtbase);
2232
2233 pl022->clk = devm_clk_get(&adev->dev, NULL);
2234 if (IS_ERR(pl022->clk)) {
2235 status = PTR_ERR(pl022->clk);
2236 dev_err(&adev->dev, "could not retrieve SSP/SPI bus clock\n");
2237 goto err_no_clk;
2238 }
2239
2240 status = clk_prepare_enable(pl022->clk);
2241 if (status) {
2242 dev_err(&adev->dev, "could not enable SSP/SPI bus clock\n");
2243 goto err_no_clk_en;
2244 }
2245
2246 /* Initialize transfer pump */
2247 tasklet_init(&pl022->pump_transfers, pump_transfers,
2248 (unsigned long)pl022);
2249
2250 /* Disable SSP */
2251 writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)),
2252 SSP_CR1(pl022->virtbase));
2253 load_ssp_default_config(pl022);
2254
2255 status = devm_request_irq(dev, adev->irq[0], pl022_interrupt_handler,
2256 0, "pl022", pl022);
2257 if (status < 0) {
2258 dev_err(&adev->dev, "probe - cannot get IRQ (%d)\n", status);
2259 goto err_no_irq;
2260 }
2261
2262 /* Get DMA channels, try autoconfiguration first */
2263 status = pl022_dma_autoprobe(pl022);
2264 if (status == -EPROBE_DEFER) {
2265 dev_dbg(dev, "deferring probe to get DMA channel\n");
2266 goto err_no_irq;
2267 }
2268
2269 /* If that failed, use channels from platform_info */
2270 if (status == 0)
2271 platform_info->enable_dma = 1;
2272 else if (platform_info->enable_dma) {
2273 status = pl022_dma_probe(pl022);
2274 if (status != 0)
2275 platform_info->enable_dma = 0;
2276 }
2277
2278 /* Register with the SPI framework */
2279 amba_set_drvdata(adev, pl022);
2280 status = devm_spi_register_master(&adev->dev, master);
2281 if (status != 0) {
2282 dev_err(&adev->dev,
2283 "probe - problem registering spi master\n");
2284 goto err_spi_register;
2285 }
2286 dev_dbg(dev, "probe succeeded\n");
2287
2288 /* let runtime pm put suspend */
2289 if (platform_info->autosuspend_delay > 0) {
2290 dev_info(&adev->dev,
2291 "will use autosuspend for runtime pm, delay %dms\n",
2292 platform_info->autosuspend_delay);
2293 pm_runtime_set_autosuspend_delay(dev,
2294 platform_info->autosuspend_delay);
2295 pm_runtime_use_autosuspend(dev);
2296 }
2297 pm_runtime_put(dev);
2298
2299 return 0;
2300
2301 err_spi_register:
2302 if (platform_info->enable_dma)
2303 pl022_dma_remove(pl022);
2304 err_no_irq:
2305 clk_disable_unprepare(pl022->clk);
2306 err_no_clk_en:
2307 err_no_clk:
2308 err_no_ioremap:
2309 amba_release_regions(adev);
2310 err_no_ioregion:
2311 err_no_gpio:
2312 err_no_mem:
2313 spi_master_put(master);
2314 return status;
2315}
2316
2317static int
2318pl022_remove(struct amba_device *adev)
2319{
2320 struct pl022 *pl022 = amba_get_drvdata(adev);
2321
2322 if (!pl022)
2323 return 0;
2324
2325 /*
2326 * undo pm_runtime_put() in probe. I assume that we're not
2327 * accessing the primecell here.
2328 */
2329 pm_runtime_get_noresume(&adev->dev);
2330
2331 load_ssp_default_config(pl022);
2332 if (pl022->master_info->enable_dma)
2333 pl022_dma_remove(pl022);
2334
2335 clk_disable_unprepare(pl022->clk);
2336 amba_release_regions(adev);
2337 tasklet_disable(&pl022->pump_transfers);
2338 return 0;
2339}
2340
2341#ifdef CONFIG_PM_SLEEP
2342static int pl022_suspend(struct device *dev)
2343{
2344 struct pl022 *pl022 = dev_get_drvdata(dev);
2345 int ret;
2346
2347 ret = spi_master_suspend(pl022->master);
2348 if (ret)
2349 return ret;
2350
2351 ret = pm_runtime_force_suspend(dev);
2352 if (ret) {
2353 spi_master_resume(pl022->master);
2354 return ret;
2355 }
2356
2357 pinctrl_pm_select_sleep_state(dev);
2358
2359 dev_dbg(dev, "suspended\n");
2360 return 0;
2361}
2362
2363static int pl022_resume(struct device *dev)
2364{
2365 struct pl022 *pl022 = dev_get_drvdata(dev);
2366 int ret;
2367
2368 ret = pm_runtime_force_resume(dev);
2369 if (ret)
2370 dev_err(dev, "problem resuming\n");
2371
2372 /* Start the queue running */
2373 ret = spi_master_resume(pl022->master);
2374 if (!ret)
2375 dev_dbg(dev, "resumed\n");
2376
2377 return ret;
2378}
2379#endif
2380
2381#ifdef CONFIG_PM
2382static int pl022_runtime_suspend(struct device *dev)
2383{
2384 struct pl022 *pl022 = dev_get_drvdata(dev);
2385
2386 clk_disable_unprepare(pl022->clk);
2387 pinctrl_pm_select_idle_state(dev);
2388
2389 return 0;
2390}
2391
2392static int pl022_runtime_resume(struct device *dev)
2393{
2394 struct pl022 *pl022 = dev_get_drvdata(dev);
2395
2396 pinctrl_pm_select_default_state(dev);
2397 clk_prepare_enable(pl022->clk);
2398
2399 return 0;
2400}
2401#endif
2402
2403static const struct dev_pm_ops pl022_dev_pm_ops = {
2404 SET_SYSTEM_SLEEP_PM_OPS(pl022_suspend, pl022_resume)
2405 SET_RUNTIME_PM_OPS(pl022_runtime_suspend, pl022_runtime_resume, NULL)
2406};
2407
2408static struct vendor_data vendor_arm = {
2409 .fifodepth = 8,
2410 .max_bpw = 16,
2411 .unidir = false,
2412 .extended_cr = false,
2413 .pl023 = false,
2414 .loopback = true,
2415 .internal_cs_ctrl = false,
2416};
2417
2418static struct vendor_data vendor_st = {
2419 .fifodepth = 32,
2420 .max_bpw = 32,
2421 .unidir = false,
2422 .extended_cr = true,
2423 .pl023 = false,
2424 .loopback = true,
2425 .internal_cs_ctrl = false,
2426};
2427
2428static struct vendor_data vendor_st_pl023 = {
2429 .fifodepth = 32,
2430 .max_bpw = 32,
2431 .unidir = false,
2432 .extended_cr = true,
2433 .pl023 = true,
2434 .loopback = false,
2435 .internal_cs_ctrl = false,
2436};
2437
2438static struct vendor_data vendor_lsi = {
2439 .fifodepth = 8,
2440 .max_bpw = 16,
2441 .unidir = false,
2442 .extended_cr = false,
2443 .pl023 = false,
2444 .loopback = true,
2445 .internal_cs_ctrl = true,
2446};
2447
2448static const struct amba_id pl022_ids[] = {
2449 {
2450 /*
2451 * ARM PL022 variant, this has a 16bit wide
2452 * and 8 locations deep TX/RX FIFO
2453 */
2454 .id = 0x00041022,
2455 .mask = 0x000fffff,
2456 .data = &vendor_arm,
2457 },
2458 {
2459 /*
2460 * ST Micro derivative, this has 32bit wide
2461 * and 32 locations deep TX/RX FIFO
2462 */
2463 .id = 0x01080022,
2464 .mask = 0xffffffff,
2465 .data = &vendor_st,
2466 },
2467 {
2468 /*
2469 * ST-Ericsson derivative "PL023" (this is not
2470 * an official ARM number), this is a PL022 SSP block
2471 * stripped to SPI mode only, it has 32bit wide
2472 * and 32 locations deep TX/RX FIFO but no extended
2473 * CR0/CR1 register
2474 */
2475 .id = 0x00080023,
2476 .mask = 0xffffffff,
2477 .data = &vendor_st_pl023,
2478 },
2479 {
2480 /*
2481 * PL022 variant that has a chip select control register whih
2482 * allows control of 5 output signals nCS[0:4].
2483 */
2484 .id = 0x000b6022,
2485 .mask = 0x000fffff,
2486 .data = &vendor_lsi,
2487 },
2488 { 0, 0 },
2489};
2490
2491MODULE_DEVICE_TABLE(amba, pl022_ids);
2492
2493static struct amba_driver pl022_driver = {
2494 .drv = {
2495 .name = "ssp-pl022",
2496 .pm = &pl022_dev_pm_ops,
2497 },
2498 .id_table = pl022_ids,
2499 .probe = pl022_probe,
2500 .remove = pl022_remove,
2501};
2502
2503static int __init pl022_init(void)
2504{
2505 return amba_driver_register(&pl022_driver);
2506}
2507subsys_initcall(pl022_init);
2508
2509static void __exit pl022_exit(void)
2510{
2511 amba_driver_unregister(&pl022_driver);
2512}
2513module_exit(pl022_exit);
2514
2515MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
2516MODULE_DESCRIPTION("PL022 SSP Controller Driver");
2517MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * A driver for the ARM PL022 PrimeCell SSP/SPI bus master.
4 *
5 * Copyright (C) 2008-2012 ST-Ericsson AB
6 * Copyright (C) 2006 STMicroelectronics Pvt. Ltd.
7 *
8 * Author: Linus Walleij <linus.walleij@stericsson.com>
9 *
10 * Initial version inspired by:
11 * linux-2.6.17-rc3-mm1/drivers/spi/pxa2xx_spi.c
12 * Initial adoption to PL022 by:
13 * Sachin Verma <sachin.verma@st.com>
14 */
15
16#include <linux/init.h>
17#include <linux/module.h>
18#include <linux/device.h>
19#include <linux/ioport.h>
20#include <linux/errno.h>
21#include <linux/interrupt.h>
22#include <linux/spi/spi.h>
23#include <linux/delay.h>
24#include <linux/clk.h>
25#include <linux/err.h>
26#include <linux/amba/bus.h>
27#include <linux/amba/pl022.h>
28#include <linux/io.h>
29#include <linux/slab.h>
30#include <linux/dmaengine.h>
31#include <linux/dma-mapping.h>
32#include <linux/scatterlist.h>
33#include <linux/pm_runtime.h>
34#include <linux/gpio.h>
35#include <linux/of_gpio.h>
36#include <linux/pinctrl/consumer.h>
37
38/*
39 * This macro is used to define some register default values.
40 * reg is masked with mask, the OR:ed with an (again masked)
41 * val shifted sb steps to the left.
42 */
43#define SSP_WRITE_BITS(reg, val, mask, sb) \
44 ((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask))))
45
46/*
47 * This macro is also used to define some default values.
48 * It will just shift val by sb steps to the left and mask
49 * the result with mask.
50 */
51#define GEN_MASK_BITS(val, mask, sb) \
52 (((val)<<(sb)) & (mask))
53
54#define DRIVE_TX 0
55#define DO_NOT_DRIVE_TX 1
56
57#define DO_NOT_QUEUE_DMA 0
58#define QUEUE_DMA 1
59
60#define RX_TRANSFER 1
61#define TX_TRANSFER 2
62
63/*
64 * Macros to access SSP Registers with their offsets
65 */
66#define SSP_CR0(r) (r + 0x000)
67#define SSP_CR1(r) (r + 0x004)
68#define SSP_DR(r) (r + 0x008)
69#define SSP_SR(r) (r + 0x00C)
70#define SSP_CPSR(r) (r + 0x010)
71#define SSP_IMSC(r) (r + 0x014)
72#define SSP_RIS(r) (r + 0x018)
73#define SSP_MIS(r) (r + 0x01C)
74#define SSP_ICR(r) (r + 0x020)
75#define SSP_DMACR(r) (r + 0x024)
76#define SSP_CSR(r) (r + 0x030) /* vendor extension */
77#define SSP_ITCR(r) (r + 0x080)
78#define SSP_ITIP(r) (r + 0x084)
79#define SSP_ITOP(r) (r + 0x088)
80#define SSP_TDR(r) (r + 0x08C)
81
82#define SSP_PID0(r) (r + 0xFE0)
83#define SSP_PID1(r) (r + 0xFE4)
84#define SSP_PID2(r) (r + 0xFE8)
85#define SSP_PID3(r) (r + 0xFEC)
86
87#define SSP_CID0(r) (r + 0xFF0)
88#define SSP_CID1(r) (r + 0xFF4)
89#define SSP_CID2(r) (r + 0xFF8)
90#define SSP_CID3(r) (r + 0xFFC)
91
92/*
93 * SSP Control Register 0 - SSP_CR0
94 */
95#define SSP_CR0_MASK_DSS (0x0FUL << 0)
96#define SSP_CR0_MASK_FRF (0x3UL << 4)
97#define SSP_CR0_MASK_SPO (0x1UL << 6)
98#define SSP_CR0_MASK_SPH (0x1UL << 7)
99#define SSP_CR0_MASK_SCR (0xFFUL << 8)
100
101/*
102 * The ST version of this block moves som bits
103 * in SSP_CR0 and extends it to 32 bits
104 */
105#define SSP_CR0_MASK_DSS_ST (0x1FUL << 0)
106#define SSP_CR0_MASK_HALFDUP_ST (0x1UL << 5)
107#define SSP_CR0_MASK_CSS_ST (0x1FUL << 16)
108#define SSP_CR0_MASK_FRF_ST (0x3UL << 21)
109
110/*
111 * SSP Control Register 0 - SSP_CR1
112 */
113#define SSP_CR1_MASK_LBM (0x1UL << 0)
114#define SSP_CR1_MASK_SSE (0x1UL << 1)
115#define SSP_CR1_MASK_MS (0x1UL << 2)
116#define SSP_CR1_MASK_SOD (0x1UL << 3)
117
118/*
119 * The ST version of this block adds some bits
120 * in SSP_CR1
121 */
122#define SSP_CR1_MASK_RENDN_ST (0x1UL << 4)
123#define SSP_CR1_MASK_TENDN_ST (0x1UL << 5)
124#define SSP_CR1_MASK_MWAIT_ST (0x1UL << 6)
125#define SSP_CR1_MASK_RXIFLSEL_ST (0x7UL << 7)
126#define SSP_CR1_MASK_TXIFLSEL_ST (0x7UL << 10)
127/* This one is only in the PL023 variant */
128#define SSP_CR1_MASK_FBCLKDEL_ST (0x7UL << 13)
129
130/*
131 * SSP Status Register - SSP_SR
132 */
133#define SSP_SR_MASK_TFE (0x1UL << 0) /* Transmit FIFO empty */
134#define SSP_SR_MASK_TNF (0x1UL << 1) /* Transmit FIFO not full */
135#define SSP_SR_MASK_RNE (0x1UL << 2) /* Receive FIFO not empty */
136#define SSP_SR_MASK_RFF (0x1UL << 3) /* Receive FIFO full */
137#define SSP_SR_MASK_BSY (0x1UL << 4) /* Busy Flag */
138
139/*
140 * SSP Clock Prescale Register - SSP_CPSR
141 */
142#define SSP_CPSR_MASK_CPSDVSR (0xFFUL << 0)
143
144/*
145 * SSP Interrupt Mask Set/Clear Register - SSP_IMSC
146 */
147#define SSP_IMSC_MASK_RORIM (0x1UL << 0) /* Receive Overrun Interrupt mask */
148#define SSP_IMSC_MASK_RTIM (0x1UL << 1) /* Receive timeout Interrupt mask */
149#define SSP_IMSC_MASK_RXIM (0x1UL << 2) /* Receive FIFO Interrupt mask */
150#define SSP_IMSC_MASK_TXIM (0x1UL << 3) /* Transmit FIFO Interrupt mask */
151
152/*
153 * SSP Raw Interrupt Status Register - SSP_RIS
154 */
155/* Receive Overrun Raw Interrupt status */
156#define SSP_RIS_MASK_RORRIS (0x1UL << 0)
157/* Receive Timeout Raw Interrupt status */
158#define SSP_RIS_MASK_RTRIS (0x1UL << 1)
159/* Receive FIFO Raw Interrupt status */
160#define SSP_RIS_MASK_RXRIS (0x1UL << 2)
161/* Transmit FIFO Raw Interrupt status */
162#define SSP_RIS_MASK_TXRIS (0x1UL << 3)
163
164/*
165 * SSP Masked Interrupt Status Register - SSP_MIS
166 */
167/* Receive Overrun Masked Interrupt status */
168#define SSP_MIS_MASK_RORMIS (0x1UL << 0)
169/* Receive Timeout Masked Interrupt status */
170#define SSP_MIS_MASK_RTMIS (0x1UL << 1)
171/* Receive FIFO Masked Interrupt status */
172#define SSP_MIS_MASK_RXMIS (0x1UL << 2)
173/* Transmit FIFO Masked Interrupt status */
174#define SSP_MIS_MASK_TXMIS (0x1UL << 3)
175
176/*
177 * SSP Interrupt Clear Register - SSP_ICR
178 */
179/* Receive Overrun Raw Clear Interrupt bit */
180#define SSP_ICR_MASK_RORIC (0x1UL << 0)
181/* Receive Timeout Clear Interrupt bit */
182#define SSP_ICR_MASK_RTIC (0x1UL << 1)
183
184/*
185 * SSP DMA Control Register - SSP_DMACR
186 */
187/* Receive DMA Enable bit */
188#define SSP_DMACR_MASK_RXDMAE (0x1UL << 0)
189/* Transmit DMA Enable bit */
190#define SSP_DMACR_MASK_TXDMAE (0x1UL << 1)
191
192/*
193 * SSP Chip Select Control Register - SSP_CSR
194 * (vendor extension)
195 */
196#define SSP_CSR_CSVALUE_MASK (0x1FUL << 0)
197
198/*
199 * SSP Integration Test control Register - SSP_ITCR
200 */
201#define SSP_ITCR_MASK_ITEN (0x1UL << 0)
202#define SSP_ITCR_MASK_TESTFIFO (0x1UL << 1)
203
204/*
205 * SSP Integration Test Input Register - SSP_ITIP
206 */
207#define ITIP_MASK_SSPRXD (0x1UL << 0)
208#define ITIP_MASK_SSPFSSIN (0x1UL << 1)
209#define ITIP_MASK_SSPCLKIN (0x1UL << 2)
210#define ITIP_MASK_RXDMAC (0x1UL << 3)
211#define ITIP_MASK_TXDMAC (0x1UL << 4)
212#define ITIP_MASK_SSPTXDIN (0x1UL << 5)
213
214/*
215 * SSP Integration Test output Register - SSP_ITOP
216 */
217#define ITOP_MASK_SSPTXD (0x1UL << 0)
218#define ITOP_MASK_SSPFSSOUT (0x1UL << 1)
219#define ITOP_MASK_SSPCLKOUT (0x1UL << 2)
220#define ITOP_MASK_SSPOEn (0x1UL << 3)
221#define ITOP_MASK_SSPCTLOEn (0x1UL << 4)
222#define ITOP_MASK_RORINTR (0x1UL << 5)
223#define ITOP_MASK_RTINTR (0x1UL << 6)
224#define ITOP_MASK_RXINTR (0x1UL << 7)
225#define ITOP_MASK_TXINTR (0x1UL << 8)
226#define ITOP_MASK_INTR (0x1UL << 9)
227#define ITOP_MASK_RXDMABREQ (0x1UL << 10)
228#define ITOP_MASK_RXDMASREQ (0x1UL << 11)
229#define ITOP_MASK_TXDMABREQ (0x1UL << 12)
230#define ITOP_MASK_TXDMASREQ (0x1UL << 13)
231
232/*
233 * SSP Test Data Register - SSP_TDR
234 */
235#define TDR_MASK_TESTDATA (0xFFFFFFFF)
236
237/*
238 * Message State
239 * we use the spi_message.state (void *) pointer to
240 * hold a single state value, that's why all this
241 * (void *) casting is done here.
242 */
243#define STATE_START ((void *) 0)
244#define STATE_RUNNING ((void *) 1)
245#define STATE_DONE ((void *) 2)
246#define STATE_ERROR ((void *) -1)
247#define STATE_TIMEOUT ((void *) -2)
248
249/*
250 * SSP State - Whether Enabled or Disabled
251 */
252#define SSP_DISABLED (0)
253#define SSP_ENABLED (1)
254
255/*
256 * SSP DMA State - Whether DMA Enabled or Disabled
257 */
258#define SSP_DMA_DISABLED (0)
259#define SSP_DMA_ENABLED (1)
260
261/*
262 * SSP Clock Defaults
263 */
264#define SSP_DEFAULT_CLKRATE 0x2
265#define SSP_DEFAULT_PRESCALE 0x40
266
267/*
268 * SSP Clock Parameter ranges
269 */
270#define CPSDVR_MIN 0x02
271#define CPSDVR_MAX 0xFE
272#define SCR_MIN 0x00
273#define SCR_MAX 0xFF
274
275/*
276 * SSP Interrupt related Macros
277 */
278#define DEFAULT_SSP_REG_IMSC 0x0UL
279#define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC
280#define ENABLE_ALL_INTERRUPTS ( \
281 SSP_IMSC_MASK_RORIM | \
282 SSP_IMSC_MASK_RTIM | \
283 SSP_IMSC_MASK_RXIM | \
284 SSP_IMSC_MASK_TXIM \
285)
286
287#define CLEAR_ALL_INTERRUPTS 0x3
288
289#define SPI_POLLING_TIMEOUT 1000
290
291/*
292 * The type of reading going on on this chip
293 */
294enum ssp_reading {
295 READING_NULL,
296 READING_U8,
297 READING_U16,
298 READING_U32
299};
300
301/**
302 * The type of writing going on on this chip
303 */
304enum ssp_writing {
305 WRITING_NULL,
306 WRITING_U8,
307 WRITING_U16,
308 WRITING_U32
309};
310
311/**
312 * struct vendor_data - vendor-specific config parameters
313 * for PL022 derivates
314 * @fifodepth: depth of FIFOs (both)
315 * @max_bpw: maximum number of bits per word
316 * @unidir: supports unidirection transfers
317 * @extended_cr: 32 bit wide control register 0 with extra
318 * features and extra features in CR1 as found in the ST variants
319 * @pl023: supports a subset of the ST extensions called "PL023"
320 * @internal_cs_ctrl: supports chip select control register
321 */
322struct vendor_data {
323 int fifodepth;
324 int max_bpw;
325 bool unidir;
326 bool extended_cr;
327 bool pl023;
328 bool loopback;
329 bool internal_cs_ctrl;
330};
331
332/**
333 * struct pl022 - This is the private SSP driver data structure
334 * @adev: AMBA device model hookup
335 * @vendor: vendor data for the IP block
336 * @phybase: the physical memory where the SSP device resides
337 * @virtbase: the virtual memory where the SSP is mapped
338 * @clk: outgoing clock "SPICLK" for the SPI bus
339 * @master: SPI framework hookup
340 * @master_info: controller-specific data from machine setup
341 * @pump_transfers: Tasklet used in Interrupt Transfer mode
342 * @cur_msg: Pointer to current spi_message being processed
343 * @cur_transfer: Pointer to current spi_transfer
344 * @cur_chip: pointer to current clients chip(assigned from controller_state)
345 * @next_msg_cs_active: the next message in the queue has been examined
346 * and it was found that it uses the same chip select as the previous
347 * message, so we left it active after the previous transfer, and it's
348 * active already.
349 * @tx: current position in TX buffer to be read
350 * @tx_end: end position in TX buffer to be read
351 * @rx: current position in RX buffer to be written
352 * @rx_end: end position in RX buffer to be written
353 * @read: the type of read currently going on
354 * @write: the type of write currently going on
355 * @exp_fifo_level: expected FIFO level
356 * @dma_rx_channel: optional channel for RX DMA
357 * @dma_tx_channel: optional channel for TX DMA
358 * @sgt_rx: scattertable for the RX transfer
359 * @sgt_tx: scattertable for the TX transfer
360 * @dummypage: a dummy page used for driving data on the bus with DMA
361 * @cur_cs: current chip select (gpio)
362 * @chipselects: list of chipselects (gpios)
363 */
364struct pl022 {
365 struct amba_device *adev;
366 struct vendor_data *vendor;
367 resource_size_t phybase;
368 void __iomem *virtbase;
369 struct clk *clk;
370 struct spi_master *master;
371 struct pl022_ssp_controller *master_info;
372 /* Message per-transfer pump */
373 struct tasklet_struct pump_transfers;
374 struct spi_message *cur_msg;
375 struct spi_transfer *cur_transfer;
376 struct chip_data *cur_chip;
377 bool next_msg_cs_active;
378 void *tx;
379 void *tx_end;
380 void *rx;
381 void *rx_end;
382 enum ssp_reading read;
383 enum ssp_writing write;
384 u32 exp_fifo_level;
385 enum ssp_rx_level_trig rx_lev_trig;
386 enum ssp_tx_level_trig tx_lev_trig;
387 /* DMA settings */
388#ifdef CONFIG_DMA_ENGINE
389 struct dma_chan *dma_rx_channel;
390 struct dma_chan *dma_tx_channel;
391 struct sg_table sgt_rx;
392 struct sg_table sgt_tx;
393 char *dummypage;
394 bool dma_running;
395#endif
396 int cur_cs;
397 int *chipselects;
398};
399
400/**
401 * struct chip_data - To maintain runtime state of SSP for each client chip
402 * @cr0: Value of control register CR0 of SSP - on later ST variants this
403 * register is 32 bits wide rather than just 16
404 * @cr1: Value of control register CR1 of SSP
405 * @dmacr: Value of DMA control Register of SSP
406 * @cpsr: Value of Clock prescale register
407 * @n_bytes: how many bytes(power of 2) reqd for a given data width of client
408 * @enable_dma: Whether to enable DMA or not
409 * @read: function ptr to be used to read when doing xfer for this chip
410 * @write: function ptr to be used to write when doing xfer for this chip
411 * @cs_control: chip select callback provided by chip
412 * @xfer_type: polling/interrupt/DMA
413 *
414 * Runtime state of the SSP controller, maintained per chip,
415 * This would be set according to the current message that would be served
416 */
417struct chip_data {
418 u32 cr0;
419 u16 cr1;
420 u16 dmacr;
421 u16 cpsr;
422 u8 n_bytes;
423 bool enable_dma;
424 enum ssp_reading read;
425 enum ssp_writing write;
426 void (*cs_control) (u32 command);
427 int xfer_type;
428};
429
430/**
431 * null_cs_control - Dummy chip select function
432 * @command: select/delect the chip
433 *
434 * If no chip select function is provided by client this is used as dummy
435 * chip select
436 */
437static void null_cs_control(u32 command)
438{
439 pr_debug("pl022: dummy chip select control, CS=0x%x\n", command);
440}
441
442/**
443 * internal_cs_control - Control chip select signals via SSP_CSR.
444 * @pl022: SSP driver private data structure
445 * @command: select/delect the chip
446 *
447 * Used on controller with internal chip select control via SSP_CSR register
448 * (vendor extension). Each of the 5 LSB in the register controls one chip
449 * select signal.
450 */
451static void internal_cs_control(struct pl022 *pl022, u32 command)
452{
453 u32 tmp;
454
455 tmp = readw(SSP_CSR(pl022->virtbase));
456 if (command == SSP_CHIP_SELECT)
457 tmp &= ~BIT(pl022->cur_cs);
458 else
459 tmp |= BIT(pl022->cur_cs);
460 writew(tmp, SSP_CSR(pl022->virtbase));
461}
462
463static void pl022_cs_control(struct pl022 *pl022, u32 command)
464{
465 if (pl022->vendor->internal_cs_ctrl)
466 internal_cs_control(pl022, command);
467 else if (gpio_is_valid(pl022->cur_cs))
468 gpio_set_value(pl022->cur_cs, command);
469 else
470 pl022->cur_chip->cs_control(command);
471}
472
473/**
474 * giveback - current spi_message is over, schedule next message and call
475 * callback of this message. Assumes that caller already
476 * set message->status; dma and pio irqs are blocked
477 * @pl022: SSP driver private data structure
478 */
479static void giveback(struct pl022 *pl022)
480{
481 struct spi_transfer *last_transfer;
482 pl022->next_msg_cs_active = false;
483
484 last_transfer = list_last_entry(&pl022->cur_msg->transfers,
485 struct spi_transfer, transfer_list);
486
487 /* Delay if requested before any change in chip select */
488 if (last_transfer->delay_usecs)
489 /*
490 * FIXME: This runs in interrupt context.
491 * Is this really smart?
492 */
493 udelay(last_transfer->delay_usecs);
494
495 if (!last_transfer->cs_change) {
496 struct spi_message *next_msg;
497
498 /*
499 * cs_change was not set. We can keep the chip select
500 * enabled if there is message in the queue and it is
501 * for the same spi device.
502 *
503 * We cannot postpone this until pump_messages, because
504 * after calling msg->complete (below) the driver that
505 * sent the current message could be unloaded, which
506 * could invalidate the cs_control() callback...
507 */
508 /* get a pointer to the next message, if any */
509 next_msg = spi_get_next_queued_message(pl022->master);
510
511 /*
512 * see if the next and current messages point
513 * to the same spi device.
514 */
515 if (next_msg && next_msg->spi != pl022->cur_msg->spi)
516 next_msg = NULL;
517 if (!next_msg || pl022->cur_msg->state == STATE_ERROR)
518 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
519 else
520 pl022->next_msg_cs_active = true;
521
522 }
523
524 pl022->cur_msg = NULL;
525 pl022->cur_transfer = NULL;
526 pl022->cur_chip = NULL;
527
528 /* disable the SPI/SSP operation */
529 writew((readw(SSP_CR1(pl022->virtbase)) &
530 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
531
532 spi_finalize_current_message(pl022->master);
533}
534
535/**
536 * flush - flush the FIFO to reach a clean state
537 * @pl022: SSP driver private data structure
538 */
539static int flush(struct pl022 *pl022)
540{
541 unsigned long limit = loops_per_jiffy << 1;
542
543 dev_dbg(&pl022->adev->dev, "flush\n");
544 do {
545 while (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
546 readw(SSP_DR(pl022->virtbase));
547 } while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_BSY) && limit--);
548
549 pl022->exp_fifo_level = 0;
550
551 return limit;
552}
553
554/**
555 * restore_state - Load configuration of current chip
556 * @pl022: SSP driver private data structure
557 */
558static void restore_state(struct pl022 *pl022)
559{
560 struct chip_data *chip = pl022->cur_chip;
561
562 if (pl022->vendor->extended_cr)
563 writel(chip->cr0, SSP_CR0(pl022->virtbase));
564 else
565 writew(chip->cr0, SSP_CR0(pl022->virtbase));
566 writew(chip->cr1, SSP_CR1(pl022->virtbase));
567 writew(chip->dmacr, SSP_DMACR(pl022->virtbase));
568 writew(chip->cpsr, SSP_CPSR(pl022->virtbase));
569 writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
570 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
571}
572
573/*
574 * Default SSP Register Values
575 */
576#define DEFAULT_SSP_REG_CR0 ( \
577 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0) | \
578 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 4) | \
579 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
580 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
581 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
582)
583
584/* ST versions have slightly different bit layout */
585#define DEFAULT_SSP_REG_CR0_ST ( \
586 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
587 GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, SSP_CR0_MASK_HALFDUP_ST, 5) | \
588 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
589 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
590 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \
591 GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS_ST, 16) | \
592 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF_ST, 21) \
593)
594
595/* The PL023 version is slightly different again */
596#define DEFAULT_SSP_REG_CR0_ST_PL023 ( \
597 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
598 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
599 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
600 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
601)
602
603#define DEFAULT_SSP_REG_CR1 ( \
604 GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \
605 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
606 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
607 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) \
608)
609
610/* ST versions extend this register to use all 16 bits */
611#define DEFAULT_SSP_REG_CR1_ST ( \
612 DEFAULT_SSP_REG_CR1 | \
613 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
614 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
615 GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT_ST, 6) |\
616 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
617 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) \
618)
619
620/*
621 * The PL023 variant has further differences: no loopback mode, no microwire
622 * support, and a new clock feedback delay setting.
623 */
624#define DEFAULT_SSP_REG_CR1_ST_PL023 ( \
625 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
626 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
627 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \
628 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
629 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
630 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
631 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) | \
632 GEN_MASK_BITS(SSP_FEEDBACK_CLK_DELAY_NONE, SSP_CR1_MASK_FBCLKDEL_ST, 13) \
633)
634
635#define DEFAULT_SSP_REG_CPSR ( \
636 GEN_MASK_BITS(SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \
637)
638
639#define DEFAULT_SSP_REG_DMACR (\
640 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \
641 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \
642)
643
644/**
645 * load_ssp_default_config - Load default configuration for SSP
646 * @pl022: SSP driver private data structure
647 */
648static void load_ssp_default_config(struct pl022 *pl022)
649{
650 if (pl022->vendor->pl023) {
651 writel(DEFAULT_SSP_REG_CR0_ST_PL023, SSP_CR0(pl022->virtbase));
652 writew(DEFAULT_SSP_REG_CR1_ST_PL023, SSP_CR1(pl022->virtbase));
653 } else if (pl022->vendor->extended_cr) {
654 writel(DEFAULT_SSP_REG_CR0_ST, SSP_CR0(pl022->virtbase));
655 writew(DEFAULT_SSP_REG_CR1_ST, SSP_CR1(pl022->virtbase));
656 } else {
657 writew(DEFAULT_SSP_REG_CR0, SSP_CR0(pl022->virtbase));
658 writew(DEFAULT_SSP_REG_CR1, SSP_CR1(pl022->virtbase));
659 }
660 writew(DEFAULT_SSP_REG_DMACR, SSP_DMACR(pl022->virtbase));
661 writew(DEFAULT_SSP_REG_CPSR, SSP_CPSR(pl022->virtbase));
662 writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
663 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
664}
665
666/**
667 * This will write to TX and read from RX according to the parameters
668 * set in pl022.
669 */
670static void readwriter(struct pl022 *pl022)
671{
672
673 /*
674 * The FIFO depth is different between primecell variants.
675 * I believe filling in too much in the FIFO might cause
676 * errons in 8bit wide transfers on ARM variants (just 8 words
677 * FIFO, means only 8x8 = 64 bits in FIFO) at least.
678 *
679 * To prevent this issue, the TX FIFO is only filled to the
680 * unused RX FIFO fill length, regardless of what the TX
681 * FIFO status flag indicates.
682 */
683 dev_dbg(&pl022->adev->dev,
684 "%s, rx: %p, rxend: %p, tx: %p, txend: %p\n",
685 __func__, pl022->rx, pl022->rx_end, pl022->tx, pl022->tx_end);
686
687 /* Read as much as you can */
688 while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
689 && (pl022->rx < pl022->rx_end)) {
690 switch (pl022->read) {
691 case READING_NULL:
692 readw(SSP_DR(pl022->virtbase));
693 break;
694 case READING_U8:
695 *(u8 *) (pl022->rx) =
696 readw(SSP_DR(pl022->virtbase)) & 0xFFU;
697 break;
698 case READING_U16:
699 *(u16 *) (pl022->rx) =
700 (u16) readw(SSP_DR(pl022->virtbase));
701 break;
702 case READING_U32:
703 *(u32 *) (pl022->rx) =
704 readl(SSP_DR(pl022->virtbase));
705 break;
706 }
707 pl022->rx += (pl022->cur_chip->n_bytes);
708 pl022->exp_fifo_level--;
709 }
710 /*
711 * Write as much as possible up to the RX FIFO size
712 */
713 while ((pl022->exp_fifo_level < pl022->vendor->fifodepth)
714 && (pl022->tx < pl022->tx_end)) {
715 switch (pl022->write) {
716 case WRITING_NULL:
717 writew(0x0, SSP_DR(pl022->virtbase));
718 break;
719 case WRITING_U8:
720 writew(*(u8 *) (pl022->tx), SSP_DR(pl022->virtbase));
721 break;
722 case WRITING_U16:
723 writew((*(u16 *) (pl022->tx)), SSP_DR(pl022->virtbase));
724 break;
725 case WRITING_U32:
726 writel(*(u32 *) (pl022->tx), SSP_DR(pl022->virtbase));
727 break;
728 }
729 pl022->tx += (pl022->cur_chip->n_bytes);
730 pl022->exp_fifo_level++;
731 /*
732 * This inner reader takes care of things appearing in the RX
733 * FIFO as we're transmitting. This will happen a lot since the
734 * clock starts running when you put things into the TX FIFO,
735 * and then things are continuously clocked into the RX FIFO.
736 */
737 while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
738 && (pl022->rx < pl022->rx_end)) {
739 switch (pl022->read) {
740 case READING_NULL:
741 readw(SSP_DR(pl022->virtbase));
742 break;
743 case READING_U8:
744 *(u8 *) (pl022->rx) =
745 readw(SSP_DR(pl022->virtbase)) & 0xFFU;
746 break;
747 case READING_U16:
748 *(u16 *) (pl022->rx) =
749 (u16) readw(SSP_DR(pl022->virtbase));
750 break;
751 case READING_U32:
752 *(u32 *) (pl022->rx) =
753 readl(SSP_DR(pl022->virtbase));
754 break;
755 }
756 pl022->rx += (pl022->cur_chip->n_bytes);
757 pl022->exp_fifo_level--;
758 }
759 }
760 /*
761 * When we exit here the TX FIFO should be full and the RX FIFO
762 * should be empty
763 */
764}
765
766/**
767 * next_transfer - Move to the Next transfer in the current spi message
768 * @pl022: SSP driver private data structure
769 *
770 * This function moves though the linked list of spi transfers in the
771 * current spi message and returns with the state of current spi
772 * message i.e whether its last transfer is done(STATE_DONE) or
773 * Next transfer is ready(STATE_RUNNING)
774 */
775static void *next_transfer(struct pl022 *pl022)
776{
777 struct spi_message *msg = pl022->cur_msg;
778 struct spi_transfer *trans = pl022->cur_transfer;
779
780 /* Move to next transfer */
781 if (trans->transfer_list.next != &msg->transfers) {
782 pl022->cur_transfer =
783 list_entry(trans->transfer_list.next,
784 struct spi_transfer, transfer_list);
785 return STATE_RUNNING;
786 }
787 return STATE_DONE;
788}
789
790/*
791 * This DMA functionality is only compiled in if we have
792 * access to the generic DMA devices/DMA engine.
793 */
794#ifdef CONFIG_DMA_ENGINE
795static void unmap_free_dma_scatter(struct pl022 *pl022)
796{
797 /* Unmap and free the SG tables */
798 dma_unmap_sg(pl022->dma_tx_channel->device->dev, pl022->sgt_tx.sgl,
799 pl022->sgt_tx.nents, DMA_TO_DEVICE);
800 dma_unmap_sg(pl022->dma_rx_channel->device->dev, pl022->sgt_rx.sgl,
801 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
802 sg_free_table(&pl022->sgt_rx);
803 sg_free_table(&pl022->sgt_tx);
804}
805
806static void dma_callback(void *data)
807{
808 struct pl022 *pl022 = data;
809 struct spi_message *msg = pl022->cur_msg;
810
811 BUG_ON(!pl022->sgt_rx.sgl);
812
813#ifdef VERBOSE_DEBUG
814 /*
815 * Optionally dump out buffers to inspect contents, this is
816 * good if you want to convince yourself that the loopback
817 * read/write contents are the same, when adopting to a new
818 * DMA engine.
819 */
820 {
821 struct scatterlist *sg;
822 unsigned int i;
823
824 dma_sync_sg_for_cpu(&pl022->adev->dev,
825 pl022->sgt_rx.sgl,
826 pl022->sgt_rx.nents,
827 DMA_FROM_DEVICE);
828
829 for_each_sg(pl022->sgt_rx.sgl, sg, pl022->sgt_rx.nents, i) {
830 dev_dbg(&pl022->adev->dev, "SPI RX SG ENTRY: %d", i);
831 print_hex_dump(KERN_ERR, "SPI RX: ",
832 DUMP_PREFIX_OFFSET,
833 16,
834 1,
835 sg_virt(sg),
836 sg_dma_len(sg),
837 1);
838 }
839 for_each_sg(pl022->sgt_tx.sgl, sg, pl022->sgt_tx.nents, i) {
840 dev_dbg(&pl022->adev->dev, "SPI TX SG ENTRY: %d", i);
841 print_hex_dump(KERN_ERR, "SPI TX: ",
842 DUMP_PREFIX_OFFSET,
843 16,
844 1,
845 sg_virt(sg),
846 sg_dma_len(sg),
847 1);
848 }
849 }
850#endif
851
852 unmap_free_dma_scatter(pl022);
853
854 /* Update total bytes transferred */
855 msg->actual_length += pl022->cur_transfer->len;
856 /* Move to next transfer */
857 msg->state = next_transfer(pl022);
858 if (msg->state != STATE_DONE && pl022->cur_transfer->cs_change)
859 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
860 tasklet_schedule(&pl022->pump_transfers);
861}
862
863static void setup_dma_scatter(struct pl022 *pl022,
864 void *buffer,
865 unsigned int length,
866 struct sg_table *sgtab)
867{
868 struct scatterlist *sg;
869 int bytesleft = length;
870 void *bufp = buffer;
871 int mapbytes;
872 int i;
873
874 if (buffer) {
875 for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
876 /*
877 * If there are less bytes left than what fits
878 * in the current page (plus page alignment offset)
879 * we just feed in this, else we stuff in as much
880 * as we can.
881 */
882 if (bytesleft < (PAGE_SIZE - offset_in_page(bufp)))
883 mapbytes = bytesleft;
884 else
885 mapbytes = PAGE_SIZE - offset_in_page(bufp);
886 sg_set_page(sg, virt_to_page(bufp),
887 mapbytes, offset_in_page(bufp));
888 bufp += mapbytes;
889 bytesleft -= mapbytes;
890 dev_dbg(&pl022->adev->dev,
891 "set RX/TX target page @ %p, %d bytes, %d left\n",
892 bufp, mapbytes, bytesleft);
893 }
894 } else {
895 /* Map the dummy buffer on every page */
896 for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
897 if (bytesleft < PAGE_SIZE)
898 mapbytes = bytesleft;
899 else
900 mapbytes = PAGE_SIZE;
901 sg_set_page(sg, virt_to_page(pl022->dummypage),
902 mapbytes, 0);
903 bytesleft -= mapbytes;
904 dev_dbg(&pl022->adev->dev,
905 "set RX/TX to dummy page %d bytes, %d left\n",
906 mapbytes, bytesleft);
907
908 }
909 }
910 BUG_ON(bytesleft);
911}
912
913/**
914 * configure_dma - configures the channels for the next transfer
915 * @pl022: SSP driver's private data structure
916 */
917static int configure_dma(struct pl022 *pl022)
918{
919 struct dma_slave_config rx_conf = {
920 .src_addr = SSP_DR(pl022->phybase),
921 .direction = DMA_DEV_TO_MEM,
922 .device_fc = false,
923 };
924 struct dma_slave_config tx_conf = {
925 .dst_addr = SSP_DR(pl022->phybase),
926 .direction = DMA_MEM_TO_DEV,
927 .device_fc = false,
928 };
929 unsigned int pages;
930 int ret;
931 int rx_sglen, tx_sglen;
932 struct dma_chan *rxchan = pl022->dma_rx_channel;
933 struct dma_chan *txchan = pl022->dma_tx_channel;
934 struct dma_async_tx_descriptor *rxdesc;
935 struct dma_async_tx_descriptor *txdesc;
936
937 /* Check that the channels are available */
938 if (!rxchan || !txchan)
939 return -ENODEV;
940
941 /*
942 * If supplied, the DMA burstsize should equal the FIFO trigger level.
943 * Notice that the DMA engine uses one-to-one mapping. Since we can
944 * not trigger on 2 elements this needs explicit mapping rather than
945 * calculation.
946 */
947 switch (pl022->rx_lev_trig) {
948 case SSP_RX_1_OR_MORE_ELEM:
949 rx_conf.src_maxburst = 1;
950 break;
951 case SSP_RX_4_OR_MORE_ELEM:
952 rx_conf.src_maxburst = 4;
953 break;
954 case SSP_RX_8_OR_MORE_ELEM:
955 rx_conf.src_maxburst = 8;
956 break;
957 case SSP_RX_16_OR_MORE_ELEM:
958 rx_conf.src_maxburst = 16;
959 break;
960 case SSP_RX_32_OR_MORE_ELEM:
961 rx_conf.src_maxburst = 32;
962 break;
963 default:
964 rx_conf.src_maxburst = pl022->vendor->fifodepth >> 1;
965 break;
966 }
967
968 switch (pl022->tx_lev_trig) {
969 case SSP_TX_1_OR_MORE_EMPTY_LOC:
970 tx_conf.dst_maxburst = 1;
971 break;
972 case SSP_TX_4_OR_MORE_EMPTY_LOC:
973 tx_conf.dst_maxburst = 4;
974 break;
975 case SSP_TX_8_OR_MORE_EMPTY_LOC:
976 tx_conf.dst_maxburst = 8;
977 break;
978 case SSP_TX_16_OR_MORE_EMPTY_LOC:
979 tx_conf.dst_maxburst = 16;
980 break;
981 case SSP_TX_32_OR_MORE_EMPTY_LOC:
982 tx_conf.dst_maxburst = 32;
983 break;
984 default:
985 tx_conf.dst_maxburst = pl022->vendor->fifodepth >> 1;
986 break;
987 }
988
989 switch (pl022->read) {
990 case READING_NULL:
991 /* Use the same as for writing */
992 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
993 break;
994 case READING_U8:
995 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
996 break;
997 case READING_U16:
998 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
999 break;
1000 case READING_U32:
1001 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1002 break;
1003 }
1004
1005 switch (pl022->write) {
1006 case WRITING_NULL:
1007 /* Use the same as for reading */
1008 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
1009 break;
1010 case WRITING_U8:
1011 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1012 break;
1013 case WRITING_U16:
1014 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
1015 break;
1016 case WRITING_U32:
1017 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1018 break;
1019 }
1020
1021 /* SPI pecularity: we need to read and write the same width */
1022 if (rx_conf.src_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
1023 rx_conf.src_addr_width = tx_conf.dst_addr_width;
1024 if (tx_conf.dst_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
1025 tx_conf.dst_addr_width = rx_conf.src_addr_width;
1026 BUG_ON(rx_conf.src_addr_width != tx_conf.dst_addr_width);
1027
1028 dmaengine_slave_config(rxchan, &rx_conf);
1029 dmaengine_slave_config(txchan, &tx_conf);
1030
1031 /* Create sglists for the transfers */
1032 pages = DIV_ROUND_UP(pl022->cur_transfer->len, PAGE_SIZE);
1033 dev_dbg(&pl022->adev->dev, "using %d pages for transfer\n", pages);
1034
1035 ret = sg_alloc_table(&pl022->sgt_rx, pages, GFP_ATOMIC);
1036 if (ret)
1037 goto err_alloc_rx_sg;
1038
1039 ret = sg_alloc_table(&pl022->sgt_tx, pages, GFP_ATOMIC);
1040 if (ret)
1041 goto err_alloc_tx_sg;
1042
1043 /* Fill in the scatterlists for the RX+TX buffers */
1044 setup_dma_scatter(pl022, pl022->rx,
1045 pl022->cur_transfer->len, &pl022->sgt_rx);
1046 setup_dma_scatter(pl022, pl022->tx,
1047 pl022->cur_transfer->len, &pl022->sgt_tx);
1048
1049 /* Map DMA buffers */
1050 rx_sglen = dma_map_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
1051 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
1052 if (!rx_sglen)
1053 goto err_rx_sgmap;
1054
1055 tx_sglen = dma_map_sg(txchan->device->dev, pl022->sgt_tx.sgl,
1056 pl022->sgt_tx.nents, DMA_TO_DEVICE);
1057 if (!tx_sglen)
1058 goto err_tx_sgmap;
1059
1060 /* Send both scatterlists */
1061 rxdesc = dmaengine_prep_slave_sg(rxchan,
1062 pl022->sgt_rx.sgl,
1063 rx_sglen,
1064 DMA_DEV_TO_MEM,
1065 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1066 if (!rxdesc)
1067 goto err_rxdesc;
1068
1069 txdesc = dmaengine_prep_slave_sg(txchan,
1070 pl022->sgt_tx.sgl,
1071 tx_sglen,
1072 DMA_MEM_TO_DEV,
1073 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1074 if (!txdesc)
1075 goto err_txdesc;
1076
1077 /* Put the callback on the RX transfer only, that should finish last */
1078 rxdesc->callback = dma_callback;
1079 rxdesc->callback_param = pl022;
1080
1081 /* Submit and fire RX and TX with TX last so we're ready to read! */
1082 dmaengine_submit(rxdesc);
1083 dmaengine_submit(txdesc);
1084 dma_async_issue_pending(rxchan);
1085 dma_async_issue_pending(txchan);
1086 pl022->dma_running = true;
1087
1088 return 0;
1089
1090err_txdesc:
1091 dmaengine_terminate_all(txchan);
1092err_rxdesc:
1093 dmaengine_terminate_all(rxchan);
1094 dma_unmap_sg(txchan->device->dev, pl022->sgt_tx.sgl,
1095 pl022->sgt_tx.nents, DMA_TO_DEVICE);
1096err_tx_sgmap:
1097 dma_unmap_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
1098 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
1099err_rx_sgmap:
1100 sg_free_table(&pl022->sgt_tx);
1101err_alloc_tx_sg:
1102 sg_free_table(&pl022->sgt_rx);
1103err_alloc_rx_sg:
1104 return -ENOMEM;
1105}
1106
1107static int pl022_dma_probe(struct pl022 *pl022)
1108{
1109 dma_cap_mask_t mask;
1110
1111 /* Try to acquire a generic DMA engine slave channel */
1112 dma_cap_zero(mask);
1113 dma_cap_set(DMA_SLAVE, mask);
1114 /*
1115 * We need both RX and TX channels to do DMA, else do none
1116 * of them.
1117 */
1118 pl022->dma_rx_channel = dma_request_channel(mask,
1119 pl022->master_info->dma_filter,
1120 pl022->master_info->dma_rx_param);
1121 if (!pl022->dma_rx_channel) {
1122 dev_dbg(&pl022->adev->dev, "no RX DMA channel!\n");
1123 goto err_no_rxchan;
1124 }
1125
1126 pl022->dma_tx_channel = dma_request_channel(mask,
1127 pl022->master_info->dma_filter,
1128 pl022->master_info->dma_tx_param);
1129 if (!pl022->dma_tx_channel) {
1130 dev_dbg(&pl022->adev->dev, "no TX DMA channel!\n");
1131 goto err_no_txchan;
1132 }
1133
1134 pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
1135 if (!pl022->dummypage)
1136 goto err_no_dummypage;
1137
1138 dev_info(&pl022->adev->dev, "setup for DMA on RX %s, TX %s\n",
1139 dma_chan_name(pl022->dma_rx_channel),
1140 dma_chan_name(pl022->dma_tx_channel));
1141
1142 return 0;
1143
1144err_no_dummypage:
1145 dma_release_channel(pl022->dma_tx_channel);
1146err_no_txchan:
1147 dma_release_channel(pl022->dma_rx_channel);
1148 pl022->dma_rx_channel = NULL;
1149err_no_rxchan:
1150 dev_err(&pl022->adev->dev,
1151 "Failed to work in dma mode, work without dma!\n");
1152 return -ENODEV;
1153}
1154
1155static int pl022_dma_autoprobe(struct pl022 *pl022)
1156{
1157 struct device *dev = &pl022->adev->dev;
1158 struct dma_chan *chan;
1159 int err;
1160
1161 /* automatically configure DMA channels from platform, normally using DT */
1162 chan = dma_request_slave_channel_reason(dev, "rx");
1163 if (IS_ERR(chan)) {
1164 err = PTR_ERR(chan);
1165 goto err_no_rxchan;
1166 }
1167
1168 pl022->dma_rx_channel = chan;
1169
1170 chan = dma_request_slave_channel_reason(dev, "tx");
1171 if (IS_ERR(chan)) {
1172 err = PTR_ERR(chan);
1173 goto err_no_txchan;
1174 }
1175
1176 pl022->dma_tx_channel = chan;
1177
1178 pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
1179 if (!pl022->dummypage) {
1180 err = -ENOMEM;
1181 goto err_no_dummypage;
1182 }
1183
1184 return 0;
1185
1186err_no_dummypage:
1187 dma_release_channel(pl022->dma_tx_channel);
1188 pl022->dma_tx_channel = NULL;
1189err_no_txchan:
1190 dma_release_channel(pl022->dma_rx_channel);
1191 pl022->dma_rx_channel = NULL;
1192err_no_rxchan:
1193 return err;
1194}
1195
1196static void terminate_dma(struct pl022 *pl022)
1197{
1198 struct dma_chan *rxchan = pl022->dma_rx_channel;
1199 struct dma_chan *txchan = pl022->dma_tx_channel;
1200
1201 dmaengine_terminate_all(rxchan);
1202 dmaengine_terminate_all(txchan);
1203 unmap_free_dma_scatter(pl022);
1204 pl022->dma_running = false;
1205}
1206
1207static void pl022_dma_remove(struct pl022 *pl022)
1208{
1209 if (pl022->dma_running)
1210 terminate_dma(pl022);
1211 if (pl022->dma_tx_channel)
1212 dma_release_channel(pl022->dma_tx_channel);
1213 if (pl022->dma_rx_channel)
1214 dma_release_channel(pl022->dma_rx_channel);
1215 kfree(pl022->dummypage);
1216}
1217
1218#else
1219static inline int configure_dma(struct pl022 *pl022)
1220{
1221 return -ENODEV;
1222}
1223
1224static inline int pl022_dma_autoprobe(struct pl022 *pl022)
1225{
1226 return 0;
1227}
1228
1229static inline int pl022_dma_probe(struct pl022 *pl022)
1230{
1231 return 0;
1232}
1233
1234static inline void pl022_dma_remove(struct pl022 *pl022)
1235{
1236}
1237#endif
1238
1239/**
1240 * pl022_interrupt_handler - Interrupt handler for SSP controller
1241 *
1242 * This function handles interrupts generated for an interrupt based transfer.
1243 * If a receive overrun (ROR) interrupt is there then we disable SSP, flag the
1244 * current message's state as STATE_ERROR and schedule the tasklet
1245 * pump_transfers which will do the postprocessing of the current message by
1246 * calling giveback(). Otherwise it reads data from RX FIFO till there is no
1247 * more data, and writes data in TX FIFO till it is not full. If we complete
1248 * the transfer we move to the next transfer and schedule the tasklet.
1249 */
1250static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id)
1251{
1252 struct pl022 *pl022 = dev_id;
1253 struct spi_message *msg = pl022->cur_msg;
1254 u16 irq_status = 0;
1255
1256 if (unlikely(!msg)) {
1257 dev_err(&pl022->adev->dev,
1258 "bad message state in interrupt handler");
1259 /* Never fail */
1260 return IRQ_HANDLED;
1261 }
1262
1263 /* Read the Interrupt Status Register */
1264 irq_status = readw(SSP_MIS(pl022->virtbase));
1265
1266 if (unlikely(!irq_status))
1267 return IRQ_NONE;
1268
1269 /*
1270 * This handles the FIFO interrupts, the timeout
1271 * interrupts are flatly ignored, they cannot be
1272 * trusted.
1273 */
1274 if (unlikely(irq_status & SSP_MIS_MASK_RORMIS)) {
1275 /*
1276 * Overrun interrupt - bail out since our Data has been
1277 * corrupted
1278 */
1279 dev_err(&pl022->adev->dev, "FIFO overrun\n");
1280 if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RFF)
1281 dev_err(&pl022->adev->dev,
1282 "RXFIFO is full\n");
1283
1284 /*
1285 * Disable and clear interrupts, disable SSP,
1286 * mark message with bad status so it can be
1287 * retried.
1288 */
1289 writew(DISABLE_ALL_INTERRUPTS,
1290 SSP_IMSC(pl022->virtbase));
1291 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1292 writew((readw(SSP_CR1(pl022->virtbase)) &
1293 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1294 msg->state = STATE_ERROR;
1295
1296 /* Schedule message queue handler */
1297 tasklet_schedule(&pl022->pump_transfers);
1298 return IRQ_HANDLED;
1299 }
1300
1301 readwriter(pl022);
1302
1303 if (pl022->tx == pl022->tx_end) {
1304 /* Disable Transmit interrupt, enable receive interrupt */
1305 writew((readw(SSP_IMSC(pl022->virtbase)) &
1306 ~SSP_IMSC_MASK_TXIM) | SSP_IMSC_MASK_RXIM,
1307 SSP_IMSC(pl022->virtbase));
1308 }
1309
1310 /*
1311 * Since all transactions must write as much as shall be read,
1312 * we can conclude the entire transaction once RX is complete.
1313 * At this point, all TX will always be finished.
1314 */
1315 if (pl022->rx >= pl022->rx_end) {
1316 writew(DISABLE_ALL_INTERRUPTS,
1317 SSP_IMSC(pl022->virtbase));
1318 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1319 if (unlikely(pl022->rx > pl022->rx_end)) {
1320 dev_warn(&pl022->adev->dev, "read %u surplus "
1321 "bytes (did you request an odd "
1322 "number of bytes on a 16bit bus?)\n",
1323 (u32) (pl022->rx - pl022->rx_end));
1324 }
1325 /* Update total bytes transferred */
1326 msg->actual_length += pl022->cur_transfer->len;
1327 /* Move to next transfer */
1328 msg->state = next_transfer(pl022);
1329 if (msg->state != STATE_DONE && pl022->cur_transfer->cs_change)
1330 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
1331 tasklet_schedule(&pl022->pump_transfers);
1332 return IRQ_HANDLED;
1333 }
1334
1335 return IRQ_HANDLED;
1336}
1337
1338/**
1339 * This sets up the pointers to memory for the next message to
1340 * send out on the SPI bus.
1341 */
1342static int set_up_next_transfer(struct pl022 *pl022,
1343 struct spi_transfer *transfer)
1344{
1345 int residue;
1346
1347 /* Sanity check the message for this bus width */
1348 residue = pl022->cur_transfer->len % pl022->cur_chip->n_bytes;
1349 if (unlikely(residue != 0)) {
1350 dev_err(&pl022->adev->dev,
1351 "message of %u bytes to transmit but the current "
1352 "chip bus has a data width of %u bytes!\n",
1353 pl022->cur_transfer->len,
1354 pl022->cur_chip->n_bytes);
1355 dev_err(&pl022->adev->dev, "skipping this message\n");
1356 return -EIO;
1357 }
1358 pl022->tx = (void *)transfer->tx_buf;
1359 pl022->tx_end = pl022->tx + pl022->cur_transfer->len;
1360 pl022->rx = (void *)transfer->rx_buf;
1361 pl022->rx_end = pl022->rx + pl022->cur_transfer->len;
1362 pl022->write =
1363 pl022->tx ? pl022->cur_chip->write : WRITING_NULL;
1364 pl022->read = pl022->rx ? pl022->cur_chip->read : READING_NULL;
1365 return 0;
1366}
1367
1368/**
1369 * pump_transfers - Tasklet function which schedules next transfer
1370 * when running in interrupt or DMA transfer mode.
1371 * @data: SSP driver private data structure
1372 *
1373 */
1374static void pump_transfers(unsigned long data)
1375{
1376 struct pl022 *pl022 = (struct pl022 *) data;
1377 struct spi_message *message = NULL;
1378 struct spi_transfer *transfer = NULL;
1379 struct spi_transfer *previous = NULL;
1380
1381 /* Get current state information */
1382 message = pl022->cur_msg;
1383 transfer = pl022->cur_transfer;
1384
1385 /* Handle for abort */
1386 if (message->state == STATE_ERROR) {
1387 message->status = -EIO;
1388 giveback(pl022);
1389 return;
1390 }
1391
1392 /* Handle end of message */
1393 if (message->state == STATE_DONE) {
1394 message->status = 0;
1395 giveback(pl022);
1396 return;
1397 }
1398
1399 /* Delay if requested at end of transfer before CS change */
1400 if (message->state == STATE_RUNNING) {
1401 previous = list_entry(transfer->transfer_list.prev,
1402 struct spi_transfer,
1403 transfer_list);
1404 if (previous->delay_usecs)
1405 /*
1406 * FIXME: This runs in interrupt context.
1407 * Is this really smart?
1408 */
1409 udelay(previous->delay_usecs);
1410
1411 /* Reselect chip select only if cs_change was requested */
1412 if (previous->cs_change)
1413 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1414 } else {
1415 /* STATE_START */
1416 message->state = STATE_RUNNING;
1417 }
1418
1419 if (set_up_next_transfer(pl022, transfer)) {
1420 message->state = STATE_ERROR;
1421 message->status = -EIO;
1422 giveback(pl022);
1423 return;
1424 }
1425 /* Flush the FIFOs and let's go! */
1426 flush(pl022);
1427
1428 if (pl022->cur_chip->enable_dma) {
1429 if (configure_dma(pl022)) {
1430 dev_dbg(&pl022->adev->dev,
1431 "configuration of DMA failed, fall back to interrupt mode\n");
1432 goto err_config_dma;
1433 }
1434 return;
1435 }
1436
1437err_config_dma:
1438 /* enable all interrupts except RX */
1439 writew(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM, SSP_IMSC(pl022->virtbase));
1440}
1441
1442static void do_interrupt_dma_transfer(struct pl022 *pl022)
1443{
1444 /*
1445 * Default is to enable all interrupts except RX -
1446 * this will be enabled once TX is complete
1447 */
1448 u32 irqflags = (u32)(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM);
1449
1450 /* Enable target chip, if not already active */
1451 if (!pl022->next_msg_cs_active)
1452 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1453
1454 if (set_up_next_transfer(pl022, pl022->cur_transfer)) {
1455 /* Error path */
1456 pl022->cur_msg->state = STATE_ERROR;
1457 pl022->cur_msg->status = -EIO;
1458 giveback(pl022);
1459 return;
1460 }
1461 /* If we're using DMA, set up DMA here */
1462 if (pl022->cur_chip->enable_dma) {
1463 /* Configure DMA transfer */
1464 if (configure_dma(pl022)) {
1465 dev_dbg(&pl022->adev->dev,
1466 "configuration of DMA failed, fall back to interrupt mode\n");
1467 goto err_config_dma;
1468 }
1469 /* Disable interrupts in DMA mode, IRQ from DMA controller */
1470 irqflags = DISABLE_ALL_INTERRUPTS;
1471 }
1472err_config_dma:
1473 /* Enable SSP, turn on interrupts */
1474 writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1475 SSP_CR1(pl022->virtbase));
1476 writew(irqflags, SSP_IMSC(pl022->virtbase));
1477}
1478
1479static void print_current_status(struct pl022 *pl022)
1480{
1481 u32 read_cr0;
1482 u16 read_cr1, read_dmacr, read_sr;
1483
1484 if (pl022->vendor->extended_cr)
1485 read_cr0 = readl(SSP_CR0(pl022->virtbase));
1486 else
1487 read_cr0 = readw(SSP_CR0(pl022->virtbase));
1488 read_cr1 = readw(SSP_CR1(pl022->virtbase));
1489 read_dmacr = readw(SSP_DMACR(pl022->virtbase));
1490 read_sr = readw(SSP_SR(pl022->virtbase));
1491
1492 dev_warn(&pl022->adev->dev, "spi-pl022 CR0: %x\n", read_cr0);
1493 dev_warn(&pl022->adev->dev, "spi-pl022 CR1: %x\n", read_cr1);
1494 dev_warn(&pl022->adev->dev, "spi-pl022 DMACR: %x\n", read_dmacr);
1495 dev_warn(&pl022->adev->dev, "spi-pl022 SR: %x\n", read_sr);
1496 dev_warn(&pl022->adev->dev,
1497 "spi-pl022 exp_fifo_level/fifodepth: %u/%d\n",
1498 pl022->exp_fifo_level,
1499 pl022->vendor->fifodepth);
1500
1501}
1502
1503static void do_polling_transfer(struct pl022 *pl022)
1504{
1505 struct spi_message *message = NULL;
1506 struct spi_transfer *transfer = NULL;
1507 struct spi_transfer *previous = NULL;
1508 unsigned long time, timeout;
1509
1510 message = pl022->cur_msg;
1511
1512 while (message->state != STATE_DONE) {
1513 /* Handle for abort */
1514 if (message->state == STATE_ERROR)
1515 break;
1516 transfer = pl022->cur_transfer;
1517
1518 /* Delay if requested at end of transfer */
1519 if (message->state == STATE_RUNNING) {
1520 previous =
1521 list_entry(transfer->transfer_list.prev,
1522 struct spi_transfer, transfer_list);
1523 if (previous->delay_usecs)
1524 udelay(previous->delay_usecs);
1525 if (previous->cs_change)
1526 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1527 } else {
1528 /* STATE_START */
1529 message->state = STATE_RUNNING;
1530 if (!pl022->next_msg_cs_active)
1531 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1532 }
1533
1534 /* Configuration Changing Per Transfer */
1535 if (set_up_next_transfer(pl022, transfer)) {
1536 /* Error path */
1537 message->state = STATE_ERROR;
1538 break;
1539 }
1540 /* Flush FIFOs and enable SSP */
1541 flush(pl022);
1542 writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1543 SSP_CR1(pl022->virtbase));
1544
1545 dev_dbg(&pl022->adev->dev, "polling transfer ongoing ...\n");
1546
1547 timeout = jiffies + msecs_to_jiffies(SPI_POLLING_TIMEOUT);
1548 while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end) {
1549 time = jiffies;
1550 readwriter(pl022);
1551 if (time_after(time, timeout)) {
1552 dev_warn(&pl022->adev->dev,
1553 "%s: timeout!\n", __func__);
1554 message->state = STATE_TIMEOUT;
1555 print_current_status(pl022);
1556 goto out;
1557 }
1558 cpu_relax();
1559 }
1560
1561 /* Update total byte transferred */
1562 message->actual_length += pl022->cur_transfer->len;
1563 /* Move to next transfer */
1564 message->state = next_transfer(pl022);
1565 if (message->state != STATE_DONE
1566 && pl022->cur_transfer->cs_change)
1567 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
1568 }
1569out:
1570 /* Handle end of message */
1571 if (message->state == STATE_DONE)
1572 message->status = 0;
1573 else if (message->state == STATE_TIMEOUT)
1574 message->status = -EAGAIN;
1575 else
1576 message->status = -EIO;
1577
1578 giveback(pl022);
1579 return;
1580}
1581
1582static int pl022_transfer_one_message(struct spi_master *master,
1583 struct spi_message *msg)
1584{
1585 struct pl022 *pl022 = spi_master_get_devdata(master);
1586
1587 /* Initial message state */
1588 pl022->cur_msg = msg;
1589 msg->state = STATE_START;
1590
1591 pl022->cur_transfer = list_entry(msg->transfers.next,
1592 struct spi_transfer, transfer_list);
1593
1594 /* Setup the SPI using the per chip configuration */
1595 pl022->cur_chip = spi_get_ctldata(msg->spi);
1596 pl022->cur_cs = pl022->chipselects[msg->spi->chip_select];
1597
1598 restore_state(pl022);
1599 flush(pl022);
1600
1601 if (pl022->cur_chip->xfer_type == POLLING_TRANSFER)
1602 do_polling_transfer(pl022);
1603 else
1604 do_interrupt_dma_transfer(pl022);
1605
1606 return 0;
1607}
1608
1609static int pl022_unprepare_transfer_hardware(struct spi_master *master)
1610{
1611 struct pl022 *pl022 = spi_master_get_devdata(master);
1612
1613 /* nothing more to do - disable spi/ssp and power off */
1614 writew((readw(SSP_CR1(pl022->virtbase)) &
1615 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1616
1617 return 0;
1618}
1619
1620static int verify_controller_parameters(struct pl022 *pl022,
1621 struct pl022_config_chip const *chip_info)
1622{
1623 if ((chip_info->iface < SSP_INTERFACE_MOTOROLA_SPI)
1624 || (chip_info->iface > SSP_INTERFACE_UNIDIRECTIONAL)) {
1625 dev_err(&pl022->adev->dev,
1626 "interface is configured incorrectly\n");
1627 return -EINVAL;
1628 }
1629 if ((chip_info->iface == SSP_INTERFACE_UNIDIRECTIONAL) &&
1630 (!pl022->vendor->unidir)) {
1631 dev_err(&pl022->adev->dev,
1632 "unidirectional mode not supported in this "
1633 "hardware version\n");
1634 return -EINVAL;
1635 }
1636 if ((chip_info->hierarchy != SSP_MASTER)
1637 && (chip_info->hierarchy != SSP_SLAVE)) {
1638 dev_err(&pl022->adev->dev,
1639 "hierarchy is configured incorrectly\n");
1640 return -EINVAL;
1641 }
1642 if ((chip_info->com_mode != INTERRUPT_TRANSFER)
1643 && (chip_info->com_mode != DMA_TRANSFER)
1644 && (chip_info->com_mode != POLLING_TRANSFER)) {
1645 dev_err(&pl022->adev->dev,
1646 "Communication mode is configured incorrectly\n");
1647 return -EINVAL;
1648 }
1649 switch (chip_info->rx_lev_trig) {
1650 case SSP_RX_1_OR_MORE_ELEM:
1651 case SSP_RX_4_OR_MORE_ELEM:
1652 case SSP_RX_8_OR_MORE_ELEM:
1653 /* These are always OK, all variants can handle this */
1654 break;
1655 case SSP_RX_16_OR_MORE_ELEM:
1656 if (pl022->vendor->fifodepth < 16) {
1657 dev_err(&pl022->adev->dev,
1658 "RX FIFO Trigger Level is configured incorrectly\n");
1659 return -EINVAL;
1660 }
1661 break;
1662 case SSP_RX_32_OR_MORE_ELEM:
1663 if (pl022->vendor->fifodepth < 32) {
1664 dev_err(&pl022->adev->dev,
1665 "RX FIFO Trigger Level is configured incorrectly\n");
1666 return -EINVAL;
1667 }
1668 break;
1669 default:
1670 dev_err(&pl022->adev->dev,
1671 "RX FIFO Trigger Level is configured incorrectly\n");
1672 return -EINVAL;
1673 }
1674 switch (chip_info->tx_lev_trig) {
1675 case SSP_TX_1_OR_MORE_EMPTY_LOC:
1676 case SSP_TX_4_OR_MORE_EMPTY_LOC:
1677 case SSP_TX_8_OR_MORE_EMPTY_LOC:
1678 /* These are always OK, all variants can handle this */
1679 break;
1680 case SSP_TX_16_OR_MORE_EMPTY_LOC:
1681 if (pl022->vendor->fifodepth < 16) {
1682 dev_err(&pl022->adev->dev,
1683 "TX FIFO Trigger Level is configured incorrectly\n");
1684 return -EINVAL;
1685 }
1686 break;
1687 case SSP_TX_32_OR_MORE_EMPTY_LOC:
1688 if (pl022->vendor->fifodepth < 32) {
1689 dev_err(&pl022->adev->dev,
1690 "TX FIFO Trigger Level is configured incorrectly\n");
1691 return -EINVAL;
1692 }
1693 break;
1694 default:
1695 dev_err(&pl022->adev->dev,
1696 "TX FIFO Trigger Level is configured incorrectly\n");
1697 return -EINVAL;
1698 }
1699 if (chip_info->iface == SSP_INTERFACE_NATIONAL_MICROWIRE) {
1700 if ((chip_info->ctrl_len < SSP_BITS_4)
1701 || (chip_info->ctrl_len > SSP_BITS_32)) {
1702 dev_err(&pl022->adev->dev,
1703 "CTRL LEN is configured incorrectly\n");
1704 return -EINVAL;
1705 }
1706 if ((chip_info->wait_state != SSP_MWIRE_WAIT_ZERO)
1707 && (chip_info->wait_state != SSP_MWIRE_WAIT_ONE)) {
1708 dev_err(&pl022->adev->dev,
1709 "Wait State is configured incorrectly\n");
1710 return -EINVAL;
1711 }
1712 /* Half duplex is only available in the ST Micro version */
1713 if (pl022->vendor->extended_cr) {
1714 if ((chip_info->duplex !=
1715 SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
1716 && (chip_info->duplex !=
1717 SSP_MICROWIRE_CHANNEL_HALF_DUPLEX)) {
1718 dev_err(&pl022->adev->dev,
1719 "Microwire duplex mode is configured incorrectly\n");
1720 return -EINVAL;
1721 }
1722 } else {
1723 if (chip_info->duplex != SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
1724 dev_err(&pl022->adev->dev,
1725 "Microwire half duplex mode requested,"
1726 " but this is only available in the"
1727 " ST version of PL022\n");
1728 return -EINVAL;
1729 }
1730 }
1731 return 0;
1732}
1733
1734static inline u32 spi_rate(u32 rate, u16 cpsdvsr, u16 scr)
1735{
1736 return rate / (cpsdvsr * (1 + scr));
1737}
1738
1739static int calculate_effective_freq(struct pl022 *pl022, int freq, struct
1740 ssp_clock_params * clk_freq)
1741{
1742 /* Lets calculate the frequency parameters */
1743 u16 cpsdvsr = CPSDVR_MIN, scr = SCR_MIN;
1744 u32 rate, max_tclk, min_tclk, best_freq = 0, best_cpsdvsr = 0,
1745 best_scr = 0, tmp, found = 0;
1746
1747 rate = clk_get_rate(pl022->clk);
1748 /* cpsdvscr = 2 & scr 0 */
1749 max_tclk = spi_rate(rate, CPSDVR_MIN, SCR_MIN);
1750 /* cpsdvsr = 254 & scr = 255 */
1751 min_tclk = spi_rate(rate, CPSDVR_MAX, SCR_MAX);
1752
1753 if (freq > max_tclk)
1754 dev_warn(&pl022->adev->dev,
1755 "Max speed that can be programmed is %d Hz, you requested %d\n",
1756 max_tclk, freq);
1757
1758 if (freq < min_tclk) {
1759 dev_err(&pl022->adev->dev,
1760 "Requested frequency: %d Hz is less than minimum possible %d Hz\n",
1761 freq, min_tclk);
1762 return -EINVAL;
1763 }
1764
1765 /*
1766 * best_freq will give closest possible available rate (<= requested
1767 * freq) for all values of scr & cpsdvsr.
1768 */
1769 while ((cpsdvsr <= CPSDVR_MAX) && !found) {
1770 while (scr <= SCR_MAX) {
1771 tmp = spi_rate(rate, cpsdvsr, scr);
1772
1773 if (tmp > freq) {
1774 /* we need lower freq */
1775 scr++;
1776 continue;
1777 }
1778
1779 /*
1780 * If found exact value, mark found and break.
1781 * If found more closer value, update and break.
1782 */
1783 if (tmp > best_freq) {
1784 best_freq = tmp;
1785 best_cpsdvsr = cpsdvsr;
1786 best_scr = scr;
1787
1788 if (tmp == freq)
1789 found = 1;
1790 }
1791 /*
1792 * increased scr will give lower rates, which are not
1793 * required
1794 */
1795 break;
1796 }
1797 cpsdvsr += 2;
1798 scr = SCR_MIN;
1799 }
1800
1801 WARN(!best_freq, "pl022: Matching cpsdvsr and scr not found for %d Hz rate \n",
1802 freq);
1803
1804 clk_freq->cpsdvsr = (u8) (best_cpsdvsr & 0xFF);
1805 clk_freq->scr = (u8) (best_scr & 0xFF);
1806 dev_dbg(&pl022->adev->dev,
1807 "SSP Target Frequency is: %u, Effective Frequency is %u\n",
1808 freq, best_freq);
1809 dev_dbg(&pl022->adev->dev, "SSP cpsdvsr = %d, scr = %d\n",
1810 clk_freq->cpsdvsr, clk_freq->scr);
1811
1812 return 0;
1813}
1814
1815/*
1816 * A piece of default chip info unless the platform
1817 * supplies it.
1818 */
1819static const struct pl022_config_chip pl022_default_chip_info = {
1820 .com_mode = POLLING_TRANSFER,
1821 .iface = SSP_INTERFACE_MOTOROLA_SPI,
1822 .hierarchy = SSP_SLAVE,
1823 .slave_tx_disable = DO_NOT_DRIVE_TX,
1824 .rx_lev_trig = SSP_RX_1_OR_MORE_ELEM,
1825 .tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC,
1826 .ctrl_len = SSP_BITS_8,
1827 .wait_state = SSP_MWIRE_WAIT_ZERO,
1828 .duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX,
1829 .cs_control = null_cs_control,
1830};
1831
1832/**
1833 * pl022_setup - setup function registered to SPI master framework
1834 * @spi: spi device which is requesting setup
1835 *
1836 * This function is registered to the SPI framework for this SPI master
1837 * controller. If it is the first time when setup is called by this device,
1838 * this function will initialize the runtime state for this chip and save
1839 * the same in the device structure. Else it will update the runtime info
1840 * with the updated chip info. Nothing is really being written to the
1841 * controller hardware here, that is not done until the actual transfer
1842 * commence.
1843 */
1844static int pl022_setup(struct spi_device *spi)
1845{
1846 struct pl022_config_chip const *chip_info;
1847 struct pl022_config_chip chip_info_dt;
1848 struct chip_data *chip;
1849 struct ssp_clock_params clk_freq = { .cpsdvsr = 0, .scr = 0};
1850 int status = 0;
1851 struct pl022 *pl022 = spi_master_get_devdata(spi->master);
1852 unsigned int bits = spi->bits_per_word;
1853 u32 tmp;
1854 struct device_node *np = spi->dev.of_node;
1855
1856 if (!spi->max_speed_hz)
1857 return -EINVAL;
1858
1859 /* Get controller_state if one is supplied */
1860 chip = spi_get_ctldata(spi);
1861
1862 if (chip == NULL) {
1863 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
1864 if (!chip)
1865 return -ENOMEM;
1866 dev_dbg(&spi->dev,
1867 "allocated memory for controller's runtime state\n");
1868 }
1869
1870 /* Get controller data if one is supplied */
1871 chip_info = spi->controller_data;
1872
1873 if (chip_info == NULL) {
1874 if (np) {
1875 chip_info_dt = pl022_default_chip_info;
1876
1877 chip_info_dt.hierarchy = SSP_MASTER;
1878 of_property_read_u32(np, "pl022,interface",
1879 &chip_info_dt.iface);
1880 of_property_read_u32(np, "pl022,com-mode",
1881 &chip_info_dt.com_mode);
1882 of_property_read_u32(np, "pl022,rx-level-trig",
1883 &chip_info_dt.rx_lev_trig);
1884 of_property_read_u32(np, "pl022,tx-level-trig",
1885 &chip_info_dt.tx_lev_trig);
1886 of_property_read_u32(np, "pl022,ctrl-len",
1887 &chip_info_dt.ctrl_len);
1888 of_property_read_u32(np, "pl022,wait-state",
1889 &chip_info_dt.wait_state);
1890 of_property_read_u32(np, "pl022,duplex",
1891 &chip_info_dt.duplex);
1892
1893 chip_info = &chip_info_dt;
1894 } else {
1895 chip_info = &pl022_default_chip_info;
1896 /* spi_board_info.controller_data not is supplied */
1897 dev_dbg(&spi->dev,
1898 "using default controller_data settings\n");
1899 }
1900 } else
1901 dev_dbg(&spi->dev,
1902 "using user supplied controller_data settings\n");
1903
1904 /*
1905 * We can override with custom divisors, else we use the board
1906 * frequency setting
1907 */
1908 if ((0 == chip_info->clk_freq.cpsdvsr)
1909 && (0 == chip_info->clk_freq.scr)) {
1910 status = calculate_effective_freq(pl022,
1911 spi->max_speed_hz,
1912 &clk_freq);
1913 if (status < 0)
1914 goto err_config_params;
1915 } else {
1916 memcpy(&clk_freq, &chip_info->clk_freq, sizeof(clk_freq));
1917 if ((clk_freq.cpsdvsr % 2) != 0)
1918 clk_freq.cpsdvsr =
1919 clk_freq.cpsdvsr - 1;
1920 }
1921 if ((clk_freq.cpsdvsr < CPSDVR_MIN)
1922 || (clk_freq.cpsdvsr > CPSDVR_MAX)) {
1923 status = -EINVAL;
1924 dev_err(&spi->dev,
1925 "cpsdvsr is configured incorrectly\n");
1926 goto err_config_params;
1927 }
1928
1929 status = verify_controller_parameters(pl022, chip_info);
1930 if (status) {
1931 dev_err(&spi->dev, "controller data is incorrect");
1932 goto err_config_params;
1933 }
1934
1935 pl022->rx_lev_trig = chip_info->rx_lev_trig;
1936 pl022->tx_lev_trig = chip_info->tx_lev_trig;
1937
1938 /* Now set controller state based on controller data */
1939 chip->xfer_type = chip_info->com_mode;
1940 if (!chip_info->cs_control) {
1941 chip->cs_control = null_cs_control;
1942 if (!gpio_is_valid(pl022->chipselects[spi->chip_select]))
1943 dev_warn(&spi->dev,
1944 "invalid chip select\n");
1945 } else
1946 chip->cs_control = chip_info->cs_control;
1947
1948 /* Check bits per word with vendor specific range */
1949 if ((bits <= 3) || (bits > pl022->vendor->max_bpw)) {
1950 status = -ENOTSUPP;
1951 dev_err(&spi->dev, "illegal data size for this controller!\n");
1952 dev_err(&spi->dev, "This controller can only handle 4 <= n <= %d bit words\n",
1953 pl022->vendor->max_bpw);
1954 goto err_config_params;
1955 } else if (bits <= 8) {
1956 dev_dbg(&spi->dev, "4 <= n <=8 bits per word\n");
1957 chip->n_bytes = 1;
1958 chip->read = READING_U8;
1959 chip->write = WRITING_U8;
1960 } else if (bits <= 16) {
1961 dev_dbg(&spi->dev, "9 <= n <= 16 bits per word\n");
1962 chip->n_bytes = 2;
1963 chip->read = READING_U16;
1964 chip->write = WRITING_U16;
1965 } else {
1966 dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n");
1967 chip->n_bytes = 4;
1968 chip->read = READING_U32;
1969 chip->write = WRITING_U32;
1970 }
1971
1972 /* Now Initialize all register settings required for this chip */
1973 chip->cr0 = 0;
1974 chip->cr1 = 0;
1975 chip->dmacr = 0;
1976 chip->cpsr = 0;
1977 if ((chip_info->com_mode == DMA_TRANSFER)
1978 && ((pl022->master_info)->enable_dma)) {
1979 chip->enable_dma = true;
1980 dev_dbg(&spi->dev, "DMA mode set in controller state\n");
1981 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
1982 SSP_DMACR_MASK_RXDMAE, 0);
1983 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
1984 SSP_DMACR_MASK_TXDMAE, 1);
1985 } else {
1986 chip->enable_dma = false;
1987 dev_dbg(&spi->dev, "DMA mode NOT set in controller state\n");
1988 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
1989 SSP_DMACR_MASK_RXDMAE, 0);
1990 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
1991 SSP_DMACR_MASK_TXDMAE, 1);
1992 }
1993
1994 chip->cpsr = clk_freq.cpsdvsr;
1995
1996 /* Special setup for the ST micro extended control registers */
1997 if (pl022->vendor->extended_cr) {
1998 u32 etx;
1999
2000 if (pl022->vendor->pl023) {
2001 /* These bits are only in the PL023 */
2002 SSP_WRITE_BITS(chip->cr1, chip_info->clkdelay,
2003 SSP_CR1_MASK_FBCLKDEL_ST, 13);
2004 } else {
2005 /* These bits are in the PL022 but not PL023 */
2006 SSP_WRITE_BITS(chip->cr0, chip_info->duplex,
2007 SSP_CR0_MASK_HALFDUP_ST, 5);
2008 SSP_WRITE_BITS(chip->cr0, chip_info->ctrl_len,
2009 SSP_CR0_MASK_CSS_ST, 16);
2010 SSP_WRITE_BITS(chip->cr0, chip_info->iface,
2011 SSP_CR0_MASK_FRF_ST, 21);
2012 SSP_WRITE_BITS(chip->cr1, chip_info->wait_state,
2013 SSP_CR1_MASK_MWAIT_ST, 6);
2014 }
2015 SSP_WRITE_BITS(chip->cr0, bits - 1,
2016 SSP_CR0_MASK_DSS_ST, 0);
2017
2018 if (spi->mode & SPI_LSB_FIRST) {
2019 tmp = SSP_RX_LSB;
2020 etx = SSP_TX_LSB;
2021 } else {
2022 tmp = SSP_RX_MSB;
2023 etx = SSP_TX_MSB;
2024 }
2025 SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_RENDN_ST, 4);
2026 SSP_WRITE_BITS(chip->cr1, etx, SSP_CR1_MASK_TENDN_ST, 5);
2027 SSP_WRITE_BITS(chip->cr1, chip_info->rx_lev_trig,
2028 SSP_CR1_MASK_RXIFLSEL_ST, 7);
2029 SSP_WRITE_BITS(chip->cr1, chip_info->tx_lev_trig,
2030 SSP_CR1_MASK_TXIFLSEL_ST, 10);
2031 } else {
2032 SSP_WRITE_BITS(chip->cr0, bits - 1,
2033 SSP_CR0_MASK_DSS, 0);
2034 SSP_WRITE_BITS(chip->cr0, chip_info->iface,
2035 SSP_CR0_MASK_FRF, 4);
2036 }
2037
2038 /* Stuff that is common for all versions */
2039 if (spi->mode & SPI_CPOL)
2040 tmp = SSP_CLK_POL_IDLE_HIGH;
2041 else
2042 tmp = SSP_CLK_POL_IDLE_LOW;
2043 SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPO, 6);
2044
2045 if (spi->mode & SPI_CPHA)
2046 tmp = SSP_CLK_SECOND_EDGE;
2047 else
2048 tmp = SSP_CLK_FIRST_EDGE;
2049 SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPH, 7);
2050
2051 SSP_WRITE_BITS(chip->cr0, clk_freq.scr, SSP_CR0_MASK_SCR, 8);
2052 /* Loopback is available on all versions except PL023 */
2053 if (pl022->vendor->loopback) {
2054 if (spi->mode & SPI_LOOP)
2055 tmp = LOOPBACK_ENABLED;
2056 else
2057 tmp = LOOPBACK_DISABLED;
2058 SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_LBM, 0);
2059 }
2060 SSP_WRITE_BITS(chip->cr1, SSP_DISABLED, SSP_CR1_MASK_SSE, 1);
2061 SSP_WRITE_BITS(chip->cr1, chip_info->hierarchy, SSP_CR1_MASK_MS, 2);
2062 SSP_WRITE_BITS(chip->cr1, chip_info->slave_tx_disable, SSP_CR1_MASK_SOD,
2063 3);
2064
2065 /* Save controller_state */
2066 spi_set_ctldata(spi, chip);
2067 return status;
2068 err_config_params:
2069 spi_set_ctldata(spi, NULL);
2070 kfree(chip);
2071 return status;
2072}
2073
2074/**
2075 * pl022_cleanup - cleanup function registered to SPI master framework
2076 * @spi: spi device which is requesting cleanup
2077 *
2078 * This function is registered to the SPI framework for this SPI master
2079 * controller. It will free the runtime state of chip.
2080 */
2081static void pl022_cleanup(struct spi_device *spi)
2082{
2083 struct chip_data *chip = spi_get_ctldata(spi);
2084
2085 spi_set_ctldata(spi, NULL);
2086 kfree(chip);
2087}
2088
2089static struct pl022_ssp_controller *
2090pl022_platform_data_dt_get(struct device *dev)
2091{
2092 struct device_node *np = dev->of_node;
2093 struct pl022_ssp_controller *pd;
2094 u32 tmp = 0;
2095
2096 if (!np) {
2097 dev_err(dev, "no dt node defined\n");
2098 return NULL;
2099 }
2100
2101 pd = devm_kzalloc(dev, sizeof(struct pl022_ssp_controller), GFP_KERNEL);
2102 if (!pd)
2103 return NULL;
2104
2105 pd->bus_id = -1;
2106 pd->enable_dma = 1;
2107 of_property_read_u32(np, "num-cs", &tmp);
2108 pd->num_chipselect = tmp;
2109 of_property_read_u32(np, "pl022,autosuspend-delay",
2110 &pd->autosuspend_delay);
2111 pd->rt = of_property_read_bool(np, "pl022,rt");
2112
2113 return pd;
2114}
2115
2116static int pl022_probe(struct amba_device *adev, const struct amba_id *id)
2117{
2118 struct device *dev = &adev->dev;
2119 struct pl022_ssp_controller *platform_info =
2120 dev_get_platdata(&adev->dev);
2121 struct spi_master *master;
2122 struct pl022 *pl022 = NULL; /*Data for this driver */
2123 struct device_node *np = adev->dev.of_node;
2124 int status = 0, i, num_cs;
2125
2126 dev_info(&adev->dev,
2127 "ARM PL022 driver, device ID: 0x%08x\n", adev->periphid);
2128 if (!platform_info && IS_ENABLED(CONFIG_OF))
2129 platform_info = pl022_platform_data_dt_get(dev);
2130
2131 if (!platform_info) {
2132 dev_err(dev, "probe: no platform data defined\n");
2133 return -ENODEV;
2134 }
2135
2136 if (platform_info->num_chipselect) {
2137 num_cs = platform_info->num_chipselect;
2138 } else {
2139 dev_err(dev, "probe: no chip select defined\n");
2140 return -ENODEV;
2141 }
2142
2143 /* Allocate master with space for data */
2144 master = spi_alloc_master(dev, sizeof(struct pl022));
2145 if (master == NULL) {
2146 dev_err(&adev->dev, "probe - cannot alloc SPI master\n");
2147 return -ENOMEM;
2148 }
2149
2150 pl022 = spi_master_get_devdata(master);
2151 pl022->master = master;
2152 pl022->master_info = platform_info;
2153 pl022->adev = adev;
2154 pl022->vendor = id->data;
2155 pl022->chipselects = devm_kcalloc(dev, num_cs, sizeof(int),
2156 GFP_KERNEL);
2157 if (!pl022->chipselects) {
2158 status = -ENOMEM;
2159 goto err_no_mem;
2160 }
2161
2162 /*
2163 * Bus Number Which has been Assigned to this SSP controller
2164 * on this board
2165 */
2166 master->bus_num = platform_info->bus_id;
2167 master->num_chipselect = num_cs;
2168 master->cleanup = pl022_cleanup;
2169 master->setup = pl022_setup;
2170 master->auto_runtime_pm = true;
2171 master->transfer_one_message = pl022_transfer_one_message;
2172 master->unprepare_transfer_hardware = pl022_unprepare_transfer_hardware;
2173 master->rt = platform_info->rt;
2174 master->dev.of_node = dev->of_node;
2175
2176 if (platform_info->num_chipselect && platform_info->chipselects) {
2177 for (i = 0; i < num_cs; i++)
2178 pl022->chipselects[i] = platform_info->chipselects[i];
2179 } else if (pl022->vendor->internal_cs_ctrl) {
2180 for (i = 0; i < num_cs; i++)
2181 pl022->chipselects[i] = i;
2182 } else if (IS_ENABLED(CONFIG_OF)) {
2183 for (i = 0; i < num_cs; i++) {
2184 int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
2185
2186 if (cs_gpio == -EPROBE_DEFER) {
2187 status = -EPROBE_DEFER;
2188 goto err_no_gpio;
2189 }
2190
2191 pl022->chipselects[i] = cs_gpio;
2192
2193 if (gpio_is_valid(cs_gpio)) {
2194 if (devm_gpio_request(dev, cs_gpio, "ssp-pl022"))
2195 dev_err(&adev->dev,
2196 "could not request %d gpio\n",
2197 cs_gpio);
2198 else if (gpio_direction_output(cs_gpio, 1))
2199 dev_err(&adev->dev,
2200 "could not set gpio %d as output\n",
2201 cs_gpio);
2202 }
2203 }
2204 }
2205
2206 /*
2207 * Supports mode 0-3, loopback, and active low CS. Transfers are
2208 * always MS bit first on the original pl022.
2209 */
2210 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
2211 if (pl022->vendor->extended_cr)
2212 master->mode_bits |= SPI_LSB_FIRST;
2213
2214 dev_dbg(&adev->dev, "BUSNO: %d\n", master->bus_num);
2215
2216 status = amba_request_regions(adev, NULL);
2217 if (status)
2218 goto err_no_ioregion;
2219
2220 pl022->phybase = adev->res.start;
2221 pl022->virtbase = devm_ioremap(dev, adev->res.start,
2222 resource_size(&adev->res));
2223 if (pl022->virtbase == NULL) {
2224 status = -ENOMEM;
2225 goto err_no_ioremap;
2226 }
2227 dev_info(&adev->dev, "mapped registers from %pa to %p\n",
2228 &adev->res.start, pl022->virtbase);
2229
2230 pl022->clk = devm_clk_get(&adev->dev, NULL);
2231 if (IS_ERR(pl022->clk)) {
2232 status = PTR_ERR(pl022->clk);
2233 dev_err(&adev->dev, "could not retrieve SSP/SPI bus clock\n");
2234 goto err_no_clk;
2235 }
2236
2237 status = clk_prepare_enable(pl022->clk);
2238 if (status) {
2239 dev_err(&adev->dev, "could not enable SSP/SPI bus clock\n");
2240 goto err_no_clk_en;
2241 }
2242
2243 /* Initialize transfer pump */
2244 tasklet_init(&pl022->pump_transfers, pump_transfers,
2245 (unsigned long)pl022);
2246
2247 /* Disable SSP */
2248 writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)),
2249 SSP_CR1(pl022->virtbase));
2250 load_ssp_default_config(pl022);
2251
2252 status = devm_request_irq(dev, adev->irq[0], pl022_interrupt_handler,
2253 0, "pl022", pl022);
2254 if (status < 0) {
2255 dev_err(&adev->dev, "probe - cannot get IRQ (%d)\n", status);
2256 goto err_no_irq;
2257 }
2258
2259 /* Get DMA channels, try autoconfiguration first */
2260 status = pl022_dma_autoprobe(pl022);
2261 if (status == -EPROBE_DEFER) {
2262 dev_dbg(dev, "deferring probe to get DMA channel\n");
2263 goto err_no_irq;
2264 }
2265
2266 /* If that failed, use channels from platform_info */
2267 if (status == 0)
2268 platform_info->enable_dma = 1;
2269 else if (platform_info->enable_dma) {
2270 status = pl022_dma_probe(pl022);
2271 if (status != 0)
2272 platform_info->enable_dma = 0;
2273 }
2274
2275 /* Register with the SPI framework */
2276 amba_set_drvdata(adev, pl022);
2277 status = devm_spi_register_master(&adev->dev, master);
2278 if (status != 0) {
2279 dev_err(&adev->dev,
2280 "probe - problem registering spi master\n");
2281 goto err_spi_register;
2282 }
2283 dev_dbg(dev, "probe succeeded\n");
2284
2285 /* let runtime pm put suspend */
2286 if (platform_info->autosuspend_delay > 0) {
2287 dev_info(&adev->dev,
2288 "will use autosuspend for runtime pm, delay %dms\n",
2289 platform_info->autosuspend_delay);
2290 pm_runtime_set_autosuspend_delay(dev,
2291 platform_info->autosuspend_delay);
2292 pm_runtime_use_autosuspend(dev);
2293 }
2294 pm_runtime_put(dev);
2295
2296 return 0;
2297
2298 err_spi_register:
2299 if (platform_info->enable_dma)
2300 pl022_dma_remove(pl022);
2301 err_no_irq:
2302 clk_disable_unprepare(pl022->clk);
2303 err_no_clk_en:
2304 err_no_clk:
2305 err_no_ioremap:
2306 amba_release_regions(adev);
2307 err_no_ioregion:
2308 err_no_gpio:
2309 err_no_mem:
2310 spi_master_put(master);
2311 return status;
2312}
2313
2314static int
2315pl022_remove(struct amba_device *adev)
2316{
2317 struct pl022 *pl022 = amba_get_drvdata(adev);
2318
2319 if (!pl022)
2320 return 0;
2321
2322 /*
2323 * undo pm_runtime_put() in probe. I assume that we're not
2324 * accessing the primecell here.
2325 */
2326 pm_runtime_get_noresume(&adev->dev);
2327
2328 load_ssp_default_config(pl022);
2329 if (pl022->master_info->enable_dma)
2330 pl022_dma_remove(pl022);
2331
2332 clk_disable_unprepare(pl022->clk);
2333 amba_release_regions(adev);
2334 tasklet_disable(&pl022->pump_transfers);
2335 return 0;
2336}
2337
2338#ifdef CONFIG_PM_SLEEP
2339static int pl022_suspend(struct device *dev)
2340{
2341 struct pl022 *pl022 = dev_get_drvdata(dev);
2342 int ret;
2343
2344 ret = spi_master_suspend(pl022->master);
2345 if (ret)
2346 return ret;
2347
2348 ret = pm_runtime_force_suspend(dev);
2349 if (ret) {
2350 spi_master_resume(pl022->master);
2351 return ret;
2352 }
2353
2354 pinctrl_pm_select_sleep_state(dev);
2355
2356 dev_dbg(dev, "suspended\n");
2357 return 0;
2358}
2359
2360static int pl022_resume(struct device *dev)
2361{
2362 struct pl022 *pl022 = dev_get_drvdata(dev);
2363 int ret;
2364
2365 ret = pm_runtime_force_resume(dev);
2366 if (ret)
2367 dev_err(dev, "problem resuming\n");
2368
2369 /* Start the queue running */
2370 ret = spi_master_resume(pl022->master);
2371 if (!ret)
2372 dev_dbg(dev, "resumed\n");
2373
2374 return ret;
2375}
2376#endif
2377
2378#ifdef CONFIG_PM
2379static int pl022_runtime_suspend(struct device *dev)
2380{
2381 struct pl022 *pl022 = dev_get_drvdata(dev);
2382
2383 clk_disable_unprepare(pl022->clk);
2384 pinctrl_pm_select_idle_state(dev);
2385
2386 return 0;
2387}
2388
2389static int pl022_runtime_resume(struct device *dev)
2390{
2391 struct pl022 *pl022 = dev_get_drvdata(dev);
2392
2393 pinctrl_pm_select_default_state(dev);
2394 clk_prepare_enable(pl022->clk);
2395
2396 return 0;
2397}
2398#endif
2399
2400static const struct dev_pm_ops pl022_dev_pm_ops = {
2401 SET_SYSTEM_SLEEP_PM_OPS(pl022_suspend, pl022_resume)
2402 SET_RUNTIME_PM_OPS(pl022_runtime_suspend, pl022_runtime_resume, NULL)
2403};
2404
2405static struct vendor_data vendor_arm = {
2406 .fifodepth = 8,
2407 .max_bpw = 16,
2408 .unidir = false,
2409 .extended_cr = false,
2410 .pl023 = false,
2411 .loopback = true,
2412 .internal_cs_ctrl = false,
2413};
2414
2415static struct vendor_data vendor_st = {
2416 .fifodepth = 32,
2417 .max_bpw = 32,
2418 .unidir = false,
2419 .extended_cr = true,
2420 .pl023 = false,
2421 .loopback = true,
2422 .internal_cs_ctrl = false,
2423};
2424
2425static struct vendor_data vendor_st_pl023 = {
2426 .fifodepth = 32,
2427 .max_bpw = 32,
2428 .unidir = false,
2429 .extended_cr = true,
2430 .pl023 = true,
2431 .loopback = false,
2432 .internal_cs_ctrl = false,
2433};
2434
2435static struct vendor_data vendor_lsi = {
2436 .fifodepth = 8,
2437 .max_bpw = 16,
2438 .unidir = false,
2439 .extended_cr = false,
2440 .pl023 = false,
2441 .loopback = true,
2442 .internal_cs_ctrl = true,
2443};
2444
2445static const struct amba_id pl022_ids[] = {
2446 {
2447 /*
2448 * ARM PL022 variant, this has a 16bit wide
2449 * and 8 locations deep TX/RX FIFO
2450 */
2451 .id = 0x00041022,
2452 .mask = 0x000fffff,
2453 .data = &vendor_arm,
2454 },
2455 {
2456 /*
2457 * ST Micro derivative, this has 32bit wide
2458 * and 32 locations deep TX/RX FIFO
2459 */
2460 .id = 0x01080022,
2461 .mask = 0xffffffff,
2462 .data = &vendor_st,
2463 },
2464 {
2465 /*
2466 * ST-Ericsson derivative "PL023" (this is not
2467 * an official ARM number), this is a PL022 SSP block
2468 * stripped to SPI mode only, it has 32bit wide
2469 * and 32 locations deep TX/RX FIFO but no extended
2470 * CR0/CR1 register
2471 */
2472 .id = 0x00080023,
2473 .mask = 0xffffffff,
2474 .data = &vendor_st_pl023,
2475 },
2476 {
2477 /*
2478 * PL022 variant that has a chip select control register whih
2479 * allows control of 5 output signals nCS[0:4].
2480 */
2481 .id = 0x000b6022,
2482 .mask = 0x000fffff,
2483 .data = &vendor_lsi,
2484 },
2485 { 0, 0 },
2486};
2487
2488MODULE_DEVICE_TABLE(amba, pl022_ids);
2489
2490static struct amba_driver pl022_driver = {
2491 .drv = {
2492 .name = "ssp-pl022",
2493 .pm = &pl022_dev_pm_ops,
2494 },
2495 .id_table = pl022_ids,
2496 .probe = pl022_probe,
2497 .remove = pl022_remove,
2498};
2499
2500static int __init pl022_init(void)
2501{
2502 return amba_driver_register(&pl022_driver);
2503}
2504subsys_initcall(pl022_init);
2505
2506static void __exit pl022_exit(void)
2507{
2508 amba_driver_unregister(&pl022_driver);
2509}
2510module_exit(pl022_exit);
2511
2512MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
2513MODULE_DESCRIPTION("PL022 SSP Controller Driver");
2514MODULE_LICENSE("GPL");