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1/*
2 * A driver for the ARM PL022 PrimeCell SSP/SPI bus master.
3 *
4 * Copyright (C) 2008-2012 ST-Ericsson AB
5 * Copyright (C) 2006 STMicroelectronics Pvt. Ltd.
6 *
7 * Author: Linus Walleij <linus.walleij@stericsson.com>
8 *
9 * Initial version inspired by:
10 * linux-2.6.17-rc3-mm1/drivers/spi/pxa2xx_spi.c
11 * Initial adoption to PL022 by:
12 * Sachin Verma <sachin.verma@st.com>
13 *
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
18 *
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
23 */
24
25#include <linux/init.h>
26#include <linux/module.h>
27#include <linux/device.h>
28#include <linux/ioport.h>
29#include <linux/errno.h>
30#include <linux/interrupt.h>
31#include <linux/spi/spi.h>
32#include <linux/delay.h>
33#include <linux/clk.h>
34#include <linux/err.h>
35#include <linux/amba/bus.h>
36#include <linux/amba/pl022.h>
37#include <linux/io.h>
38#include <linux/slab.h>
39#include <linux/dmaengine.h>
40#include <linux/dma-mapping.h>
41#include <linux/scatterlist.h>
42#include <linux/pm_runtime.h>
43#include <linux/gpio.h>
44#include <linux/of_gpio.h>
45#include <linux/pinctrl/consumer.h>
46
47/*
48 * This macro is used to define some register default values.
49 * reg is masked with mask, the OR:ed with an (again masked)
50 * val shifted sb steps to the left.
51 */
52#define SSP_WRITE_BITS(reg, val, mask, sb) \
53 ((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask))))
54
55/*
56 * This macro is also used to define some default values.
57 * It will just shift val by sb steps to the left and mask
58 * the result with mask.
59 */
60#define GEN_MASK_BITS(val, mask, sb) \
61 (((val)<<(sb)) & (mask))
62
63#define DRIVE_TX 0
64#define DO_NOT_DRIVE_TX 1
65
66#define DO_NOT_QUEUE_DMA 0
67#define QUEUE_DMA 1
68
69#define RX_TRANSFER 1
70#define TX_TRANSFER 2
71
72/*
73 * Macros to access SSP Registers with their offsets
74 */
75#define SSP_CR0(r) (r + 0x000)
76#define SSP_CR1(r) (r + 0x004)
77#define SSP_DR(r) (r + 0x008)
78#define SSP_SR(r) (r + 0x00C)
79#define SSP_CPSR(r) (r + 0x010)
80#define SSP_IMSC(r) (r + 0x014)
81#define SSP_RIS(r) (r + 0x018)
82#define SSP_MIS(r) (r + 0x01C)
83#define SSP_ICR(r) (r + 0x020)
84#define SSP_DMACR(r) (r + 0x024)
85#define SSP_CSR(r) (r + 0x030) /* vendor extension */
86#define SSP_ITCR(r) (r + 0x080)
87#define SSP_ITIP(r) (r + 0x084)
88#define SSP_ITOP(r) (r + 0x088)
89#define SSP_TDR(r) (r + 0x08C)
90
91#define SSP_PID0(r) (r + 0xFE0)
92#define SSP_PID1(r) (r + 0xFE4)
93#define SSP_PID2(r) (r + 0xFE8)
94#define SSP_PID3(r) (r + 0xFEC)
95
96#define SSP_CID0(r) (r + 0xFF0)
97#define SSP_CID1(r) (r + 0xFF4)
98#define SSP_CID2(r) (r + 0xFF8)
99#define SSP_CID3(r) (r + 0xFFC)
100
101/*
102 * SSP Control Register 0 - SSP_CR0
103 */
104#define SSP_CR0_MASK_DSS (0x0FUL << 0)
105#define SSP_CR0_MASK_FRF (0x3UL << 4)
106#define SSP_CR0_MASK_SPO (0x1UL << 6)
107#define SSP_CR0_MASK_SPH (0x1UL << 7)
108#define SSP_CR0_MASK_SCR (0xFFUL << 8)
109
110/*
111 * The ST version of this block moves som bits
112 * in SSP_CR0 and extends it to 32 bits
113 */
114#define SSP_CR0_MASK_DSS_ST (0x1FUL << 0)
115#define SSP_CR0_MASK_HALFDUP_ST (0x1UL << 5)
116#define SSP_CR0_MASK_CSS_ST (0x1FUL << 16)
117#define SSP_CR0_MASK_FRF_ST (0x3UL << 21)
118
119/*
120 * SSP Control Register 0 - SSP_CR1
121 */
122#define SSP_CR1_MASK_LBM (0x1UL << 0)
123#define SSP_CR1_MASK_SSE (0x1UL << 1)
124#define SSP_CR1_MASK_MS (0x1UL << 2)
125#define SSP_CR1_MASK_SOD (0x1UL << 3)
126
127/*
128 * The ST version of this block adds some bits
129 * in SSP_CR1
130 */
131#define SSP_CR1_MASK_RENDN_ST (0x1UL << 4)
132#define SSP_CR1_MASK_TENDN_ST (0x1UL << 5)
133#define SSP_CR1_MASK_MWAIT_ST (0x1UL << 6)
134#define SSP_CR1_MASK_RXIFLSEL_ST (0x7UL << 7)
135#define SSP_CR1_MASK_TXIFLSEL_ST (0x7UL << 10)
136/* This one is only in the PL023 variant */
137#define SSP_CR1_MASK_FBCLKDEL_ST (0x7UL << 13)
138
139/*
140 * SSP Status Register - SSP_SR
141 */
142#define SSP_SR_MASK_TFE (0x1UL << 0) /* Transmit FIFO empty */
143#define SSP_SR_MASK_TNF (0x1UL << 1) /* Transmit FIFO not full */
144#define SSP_SR_MASK_RNE (0x1UL << 2) /* Receive FIFO not empty */
145#define SSP_SR_MASK_RFF (0x1UL << 3) /* Receive FIFO full */
146#define SSP_SR_MASK_BSY (0x1UL << 4) /* Busy Flag */
147
148/*
149 * SSP Clock Prescale Register - SSP_CPSR
150 */
151#define SSP_CPSR_MASK_CPSDVSR (0xFFUL << 0)
152
153/*
154 * SSP Interrupt Mask Set/Clear Register - SSP_IMSC
155 */
156#define SSP_IMSC_MASK_RORIM (0x1UL << 0) /* Receive Overrun Interrupt mask */
157#define SSP_IMSC_MASK_RTIM (0x1UL << 1) /* Receive timeout Interrupt mask */
158#define SSP_IMSC_MASK_RXIM (0x1UL << 2) /* Receive FIFO Interrupt mask */
159#define SSP_IMSC_MASK_TXIM (0x1UL << 3) /* Transmit FIFO Interrupt mask */
160
161/*
162 * SSP Raw Interrupt Status Register - SSP_RIS
163 */
164/* Receive Overrun Raw Interrupt status */
165#define SSP_RIS_MASK_RORRIS (0x1UL << 0)
166/* Receive Timeout Raw Interrupt status */
167#define SSP_RIS_MASK_RTRIS (0x1UL << 1)
168/* Receive FIFO Raw Interrupt status */
169#define SSP_RIS_MASK_RXRIS (0x1UL << 2)
170/* Transmit FIFO Raw Interrupt status */
171#define SSP_RIS_MASK_TXRIS (0x1UL << 3)
172
173/*
174 * SSP Masked Interrupt Status Register - SSP_MIS
175 */
176/* Receive Overrun Masked Interrupt status */
177#define SSP_MIS_MASK_RORMIS (0x1UL << 0)
178/* Receive Timeout Masked Interrupt status */
179#define SSP_MIS_MASK_RTMIS (0x1UL << 1)
180/* Receive FIFO Masked Interrupt status */
181#define SSP_MIS_MASK_RXMIS (0x1UL << 2)
182/* Transmit FIFO Masked Interrupt status */
183#define SSP_MIS_MASK_TXMIS (0x1UL << 3)
184
185/*
186 * SSP Interrupt Clear Register - SSP_ICR
187 */
188/* Receive Overrun Raw Clear Interrupt bit */
189#define SSP_ICR_MASK_RORIC (0x1UL << 0)
190/* Receive Timeout Clear Interrupt bit */
191#define SSP_ICR_MASK_RTIC (0x1UL << 1)
192
193/*
194 * SSP DMA Control Register - SSP_DMACR
195 */
196/* Receive DMA Enable bit */
197#define SSP_DMACR_MASK_RXDMAE (0x1UL << 0)
198/* Transmit DMA Enable bit */
199#define SSP_DMACR_MASK_TXDMAE (0x1UL << 1)
200
201/*
202 * SSP Chip Select Control Register - SSP_CSR
203 * (vendor extension)
204 */
205#define SSP_CSR_CSVALUE_MASK (0x1FUL << 0)
206
207/*
208 * SSP Integration Test control Register - SSP_ITCR
209 */
210#define SSP_ITCR_MASK_ITEN (0x1UL << 0)
211#define SSP_ITCR_MASK_TESTFIFO (0x1UL << 1)
212
213/*
214 * SSP Integration Test Input Register - SSP_ITIP
215 */
216#define ITIP_MASK_SSPRXD (0x1UL << 0)
217#define ITIP_MASK_SSPFSSIN (0x1UL << 1)
218#define ITIP_MASK_SSPCLKIN (0x1UL << 2)
219#define ITIP_MASK_RXDMAC (0x1UL << 3)
220#define ITIP_MASK_TXDMAC (0x1UL << 4)
221#define ITIP_MASK_SSPTXDIN (0x1UL << 5)
222
223/*
224 * SSP Integration Test output Register - SSP_ITOP
225 */
226#define ITOP_MASK_SSPTXD (0x1UL << 0)
227#define ITOP_MASK_SSPFSSOUT (0x1UL << 1)
228#define ITOP_MASK_SSPCLKOUT (0x1UL << 2)
229#define ITOP_MASK_SSPOEn (0x1UL << 3)
230#define ITOP_MASK_SSPCTLOEn (0x1UL << 4)
231#define ITOP_MASK_RORINTR (0x1UL << 5)
232#define ITOP_MASK_RTINTR (0x1UL << 6)
233#define ITOP_MASK_RXINTR (0x1UL << 7)
234#define ITOP_MASK_TXINTR (0x1UL << 8)
235#define ITOP_MASK_INTR (0x1UL << 9)
236#define ITOP_MASK_RXDMABREQ (0x1UL << 10)
237#define ITOP_MASK_RXDMASREQ (0x1UL << 11)
238#define ITOP_MASK_TXDMABREQ (0x1UL << 12)
239#define ITOP_MASK_TXDMASREQ (0x1UL << 13)
240
241/*
242 * SSP Test Data Register - SSP_TDR
243 */
244#define TDR_MASK_TESTDATA (0xFFFFFFFF)
245
246/*
247 * Message State
248 * we use the spi_message.state (void *) pointer to
249 * hold a single state value, that's why all this
250 * (void *) casting is done here.
251 */
252#define STATE_START ((void *) 0)
253#define STATE_RUNNING ((void *) 1)
254#define STATE_DONE ((void *) 2)
255#define STATE_ERROR ((void *) -1)
256
257/*
258 * SSP State - Whether Enabled or Disabled
259 */
260#define SSP_DISABLED (0)
261#define SSP_ENABLED (1)
262
263/*
264 * SSP DMA State - Whether DMA Enabled or Disabled
265 */
266#define SSP_DMA_DISABLED (0)
267#define SSP_DMA_ENABLED (1)
268
269/*
270 * SSP Clock Defaults
271 */
272#define SSP_DEFAULT_CLKRATE 0x2
273#define SSP_DEFAULT_PRESCALE 0x40
274
275/*
276 * SSP Clock Parameter ranges
277 */
278#define CPSDVR_MIN 0x02
279#define CPSDVR_MAX 0xFE
280#define SCR_MIN 0x00
281#define SCR_MAX 0xFF
282
283/*
284 * SSP Interrupt related Macros
285 */
286#define DEFAULT_SSP_REG_IMSC 0x0UL
287#define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC
288#define ENABLE_ALL_INTERRUPTS ( \
289 SSP_IMSC_MASK_RORIM | \
290 SSP_IMSC_MASK_RTIM | \
291 SSP_IMSC_MASK_RXIM | \
292 SSP_IMSC_MASK_TXIM \
293)
294
295#define CLEAR_ALL_INTERRUPTS 0x3
296
297#define SPI_POLLING_TIMEOUT 1000
298
299/*
300 * The type of reading going on on this chip
301 */
302enum ssp_reading {
303 READING_NULL,
304 READING_U8,
305 READING_U16,
306 READING_U32
307};
308
309/**
310 * The type of writing going on on this chip
311 */
312enum ssp_writing {
313 WRITING_NULL,
314 WRITING_U8,
315 WRITING_U16,
316 WRITING_U32
317};
318
319/**
320 * struct vendor_data - vendor-specific config parameters
321 * for PL022 derivates
322 * @fifodepth: depth of FIFOs (both)
323 * @max_bpw: maximum number of bits per word
324 * @unidir: supports unidirection transfers
325 * @extended_cr: 32 bit wide control register 0 with extra
326 * features and extra features in CR1 as found in the ST variants
327 * @pl023: supports a subset of the ST extensions called "PL023"
328 * @internal_cs_ctrl: supports chip select control register
329 */
330struct vendor_data {
331 int fifodepth;
332 int max_bpw;
333 bool unidir;
334 bool extended_cr;
335 bool pl023;
336 bool loopback;
337 bool internal_cs_ctrl;
338};
339
340/**
341 * struct pl022 - This is the private SSP driver data structure
342 * @adev: AMBA device model hookup
343 * @vendor: vendor data for the IP block
344 * @phybase: the physical memory where the SSP device resides
345 * @virtbase: the virtual memory where the SSP is mapped
346 * @clk: outgoing clock "SPICLK" for the SPI bus
347 * @master: SPI framework hookup
348 * @master_info: controller-specific data from machine setup
349 * @pump_transfers: Tasklet used in Interrupt Transfer mode
350 * @cur_msg: Pointer to current spi_message being processed
351 * @cur_transfer: Pointer to current spi_transfer
352 * @cur_chip: pointer to current clients chip(assigned from controller_state)
353 * @next_msg_cs_active: the next message in the queue has been examined
354 * and it was found that it uses the same chip select as the previous
355 * message, so we left it active after the previous transfer, and it's
356 * active already.
357 * @tx: current position in TX buffer to be read
358 * @tx_end: end position in TX buffer to be read
359 * @rx: current position in RX buffer to be written
360 * @rx_end: end position in RX buffer to be written
361 * @read: the type of read currently going on
362 * @write: the type of write currently going on
363 * @exp_fifo_level: expected FIFO level
364 * @dma_rx_channel: optional channel for RX DMA
365 * @dma_tx_channel: optional channel for TX DMA
366 * @sgt_rx: scattertable for the RX transfer
367 * @sgt_tx: scattertable for the TX transfer
368 * @dummypage: a dummy page used for driving data on the bus with DMA
369 * @cur_cs: current chip select (gpio)
370 * @chipselects: list of chipselects (gpios)
371 */
372struct pl022 {
373 struct amba_device *adev;
374 struct vendor_data *vendor;
375 resource_size_t phybase;
376 void __iomem *virtbase;
377 struct clk *clk;
378 struct spi_master *master;
379 struct pl022_ssp_controller *master_info;
380 /* Message per-transfer pump */
381 struct tasklet_struct pump_transfers;
382 struct spi_message *cur_msg;
383 struct spi_transfer *cur_transfer;
384 struct chip_data *cur_chip;
385 bool next_msg_cs_active;
386 void *tx;
387 void *tx_end;
388 void *rx;
389 void *rx_end;
390 enum ssp_reading read;
391 enum ssp_writing write;
392 u32 exp_fifo_level;
393 enum ssp_rx_level_trig rx_lev_trig;
394 enum ssp_tx_level_trig tx_lev_trig;
395 /* DMA settings */
396#ifdef CONFIG_DMA_ENGINE
397 struct dma_chan *dma_rx_channel;
398 struct dma_chan *dma_tx_channel;
399 struct sg_table sgt_rx;
400 struct sg_table sgt_tx;
401 char *dummypage;
402 bool dma_running;
403#endif
404 int cur_cs;
405 int *chipselects;
406};
407
408/**
409 * struct chip_data - To maintain runtime state of SSP for each client chip
410 * @cr0: Value of control register CR0 of SSP - on later ST variants this
411 * register is 32 bits wide rather than just 16
412 * @cr1: Value of control register CR1 of SSP
413 * @dmacr: Value of DMA control Register of SSP
414 * @cpsr: Value of Clock prescale register
415 * @n_bytes: how many bytes(power of 2) reqd for a given data width of client
416 * @enable_dma: Whether to enable DMA or not
417 * @read: function ptr to be used to read when doing xfer for this chip
418 * @write: function ptr to be used to write when doing xfer for this chip
419 * @cs_control: chip select callback provided by chip
420 * @xfer_type: polling/interrupt/DMA
421 *
422 * Runtime state of the SSP controller, maintained per chip,
423 * This would be set according to the current message that would be served
424 */
425struct chip_data {
426 u32 cr0;
427 u16 cr1;
428 u16 dmacr;
429 u16 cpsr;
430 u8 n_bytes;
431 bool enable_dma;
432 enum ssp_reading read;
433 enum ssp_writing write;
434 void (*cs_control) (u32 command);
435 int xfer_type;
436};
437
438/**
439 * null_cs_control - Dummy chip select function
440 * @command: select/delect the chip
441 *
442 * If no chip select function is provided by client this is used as dummy
443 * chip select
444 */
445static void null_cs_control(u32 command)
446{
447 pr_debug("pl022: dummy chip select control, CS=0x%x\n", command);
448}
449
450/**
451 * internal_cs_control - Control chip select signals via SSP_CSR.
452 * @pl022: SSP driver private data structure
453 * @command: select/delect the chip
454 *
455 * Used on controller with internal chip select control via SSP_CSR register
456 * (vendor extension). Each of the 5 LSB in the register controls one chip
457 * select signal.
458 */
459static void internal_cs_control(struct pl022 *pl022, u32 command)
460{
461 u32 tmp;
462
463 tmp = readw(SSP_CSR(pl022->virtbase));
464 if (command == SSP_CHIP_SELECT)
465 tmp &= ~BIT(pl022->cur_cs);
466 else
467 tmp |= BIT(pl022->cur_cs);
468 writew(tmp, SSP_CSR(pl022->virtbase));
469}
470
471static void pl022_cs_control(struct pl022 *pl022, u32 command)
472{
473 if (pl022->vendor->internal_cs_ctrl)
474 internal_cs_control(pl022, command);
475 else if (gpio_is_valid(pl022->cur_cs))
476 gpio_set_value(pl022->cur_cs, command);
477 else
478 pl022->cur_chip->cs_control(command);
479}
480
481/**
482 * giveback - current spi_message is over, schedule next message and call
483 * callback of this message. Assumes that caller already
484 * set message->status; dma and pio irqs are blocked
485 * @pl022: SSP driver private data structure
486 */
487static void giveback(struct pl022 *pl022)
488{
489 struct spi_transfer *last_transfer;
490 pl022->next_msg_cs_active = false;
491
492 last_transfer = list_last_entry(&pl022->cur_msg->transfers,
493 struct spi_transfer, transfer_list);
494
495 /* Delay if requested before any change in chip select */
496 if (last_transfer->delay_usecs)
497 /*
498 * FIXME: This runs in interrupt context.
499 * Is this really smart?
500 */
501 udelay(last_transfer->delay_usecs);
502
503 if (!last_transfer->cs_change) {
504 struct spi_message *next_msg;
505
506 /*
507 * cs_change was not set. We can keep the chip select
508 * enabled if there is message in the queue and it is
509 * for the same spi device.
510 *
511 * We cannot postpone this until pump_messages, because
512 * after calling msg->complete (below) the driver that
513 * sent the current message could be unloaded, which
514 * could invalidate the cs_control() callback...
515 */
516 /* get a pointer to the next message, if any */
517 next_msg = spi_get_next_queued_message(pl022->master);
518
519 /*
520 * see if the next and current messages point
521 * to the same spi device.
522 */
523 if (next_msg && next_msg->spi != pl022->cur_msg->spi)
524 next_msg = NULL;
525 if (!next_msg || pl022->cur_msg->state == STATE_ERROR)
526 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
527 else
528 pl022->next_msg_cs_active = true;
529
530 }
531
532 pl022->cur_msg = NULL;
533 pl022->cur_transfer = NULL;
534 pl022->cur_chip = NULL;
535
536 /* disable the SPI/SSP operation */
537 writew((readw(SSP_CR1(pl022->virtbase)) &
538 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
539
540 spi_finalize_current_message(pl022->master);
541}
542
543/**
544 * flush - flush the FIFO to reach a clean state
545 * @pl022: SSP driver private data structure
546 */
547static int flush(struct pl022 *pl022)
548{
549 unsigned long limit = loops_per_jiffy << 1;
550
551 dev_dbg(&pl022->adev->dev, "flush\n");
552 do {
553 while (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
554 readw(SSP_DR(pl022->virtbase));
555 } while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_BSY) && limit--);
556
557 pl022->exp_fifo_level = 0;
558
559 return limit;
560}
561
562/**
563 * restore_state - Load configuration of current chip
564 * @pl022: SSP driver private data structure
565 */
566static void restore_state(struct pl022 *pl022)
567{
568 struct chip_data *chip = pl022->cur_chip;
569
570 if (pl022->vendor->extended_cr)
571 writel(chip->cr0, SSP_CR0(pl022->virtbase));
572 else
573 writew(chip->cr0, SSP_CR0(pl022->virtbase));
574 writew(chip->cr1, SSP_CR1(pl022->virtbase));
575 writew(chip->dmacr, SSP_DMACR(pl022->virtbase));
576 writew(chip->cpsr, SSP_CPSR(pl022->virtbase));
577 writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
578 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
579}
580
581/*
582 * Default SSP Register Values
583 */
584#define DEFAULT_SSP_REG_CR0 ( \
585 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0) | \
586 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 4) | \
587 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
588 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
589 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
590)
591
592/* ST versions have slightly different bit layout */
593#define DEFAULT_SSP_REG_CR0_ST ( \
594 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
595 GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, SSP_CR0_MASK_HALFDUP_ST, 5) | \
596 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
597 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
598 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \
599 GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS_ST, 16) | \
600 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF_ST, 21) \
601)
602
603/* The PL023 version is slightly different again */
604#define DEFAULT_SSP_REG_CR0_ST_PL023 ( \
605 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
606 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
607 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
608 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
609)
610
611#define DEFAULT_SSP_REG_CR1 ( \
612 GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \
613 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
614 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
615 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) \
616)
617
618/* ST versions extend this register to use all 16 bits */
619#define DEFAULT_SSP_REG_CR1_ST ( \
620 DEFAULT_SSP_REG_CR1 | \
621 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
622 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
623 GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT_ST, 6) |\
624 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
625 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) \
626)
627
628/*
629 * The PL023 variant has further differences: no loopback mode, no microwire
630 * support, and a new clock feedback delay setting.
631 */
632#define DEFAULT_SSP_REG_CR1_ST_PL023 ( \
633 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
634 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
635 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \
636 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
637 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
638 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
639 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) | \
640 GEN_MASK_BITS(SSP_FEEDBACK_CLK_DELAY_NONE, SSP_CR1_MASK_FBCLKDEL_ST, 13) \
641)
642
643#define DEFAULT_SSP_REG_CPSR ( \
644 GEN_MASK_BITS(SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \
645)
646
647#define DEFAULT_SSP_REG_DMACR (\
648 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \
649 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \
650)
651
652/**
653 * load_ssp_default_config - Load default configuration for SSP
654 * @pl022: SSP driver private data structure
655 */
656static void load_ssp_default_config(struct pl022 *pl022)
657{
658 if (pl022->vendor->pl023) {
659 writel(DEFAULT_SSP_REG_CR0_ST_PL023, SSP_CR0(pl022->virtbase));
660 writew(DEFAULT_SSP_REG_CR1_ST_PL023, SSP_CR1(pl022->virtbase));
661 } else if (pl022->vendor->extended_cr) {
662 writel(DEFAULT_SSP_REG_CR0_ST, SSP_CR0(pl022->virtbase));
663 writew(DEFAULT_SSP_REG_CR1_ST, SSP_CR1(pl022->virtbase));
664 } else {
665 writew(DEFAULT_SSP_REG_CR0, SSP_CR0(pl022->virtbase));
666 writew(DEFAULT_SSP_REG_CR1, SSP_CR1(pl022->virtbase));
667 }
668 writew(DEFAULT_SSP_REG_DMACR, SSP_DMACR(pl022->virtbase));
669 writew(DEFAULT_SSP_REG_CPSR, SSP_CPSR(pl022->virtbase));
670 writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
671 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
672}
673
674/**
675 * This will write to TX and read from RX according to the parameters
676 * set in pl022.
677 */
678static void readwriter(struct pl022 *pl022)
679{
680
681 /*
682 * The FIFO depth is different between primecell variants.
683 * I believe filling in too much in the FIFO might cause
684 * errons in 8bit wide transfers on ARM variants (just 8 words
685 * FIFO, means only 8x8 = 64 bits in FIFO) at least.
686 *
687 * To prevent this issue, the TX FIFO is only filled to the
688 * unused RX FIFO fill length, regardless of what the TX
689 * FIFO status flag indicates.
690 */
691 dev_dbg(&pl022->adev->dev,
692 "%s, rx: %p, rxend: %p, tx: %p, txend: %p\n",
693 __func__, pl022->rx, pl022->rx_end, pl022->tx, pl022->tx_end);
694
695 /* Read as much as you can */
696 while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
697 && (pl022->rx < pl022->rx_end)) {
698 switch (pl022->read) {
699 case READING_NULL:
700 readw(SSP_DR(pl022->virtbase));
701 break;
702 case READING_U8:
703 *(u8 *) (pl022->rx) =
704 readw(SSP_DR(pl022->virtbase)) & 0xFFU;
705 break;
706 case READING_U16:
707 *(u16 *) (pl022->rx) =
708 (u16) readw(SSP_DR(pl022->virtbase));
709 break;
710 case READING_U32:
711 *(u32 *) (pl022->rx) =
712 readl(SSP_DR(pl022->virtbase));
713 break;
714 }
715 pl022->rx += (pl022->cur_chip->n_bytes);
716 pl022->exp_fifo_level--;
717 }
718 /*
719 * Write as much as possible up to the RX FIFO size
720 */
721 while ((pl022->exp_fifo_level < pl022->vendor->fifodepth)
722 && (pl022->tx < pl022->tx_end)) {
723 switch (pl022->write) {
724 case WRITING_NULL:
725 writew(0x0, SSP_DR(pl022->virtbase));
726 break;
727 case WRITING_U8:
728 writew(*(u8 *) (pl022->tx), SSP_DR(pl022->virtbase));
729 break;
730 case WRITING_U16:
731 writew((*(u16 *) (pl022->tx)), SSP_DR(pl022->virtbase));
732 break;
733 case WRITING_U32:
734 writel(*(u32 *) (pl022->tx), SSP_DR(pl022->virtbase));
735 break;
736 }
737 pl022->tx += (pl022->cur_chip->n_bytes);
738 pl022->exp_fifo_level++;
739 /*
740 * This inner reader takes care of things appearing in the RX
741 * FIFO as we're transmitting. This will happen a lot since the
742 * clock starts running when you put things into the TX FIFO,
743 * and then things are continuously clocked into the RX FIFO.
744 */
745 while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
746 && (pl022->rx < pl022->rx_end)) {
747 switch (pl022->read) {
748 case READING_NULL:
749 readw(SSP_DR(pl022->virtbase));
750 break;
751 case READING_U8:
752 *(u8 *) (pl022->rx) =
753 readw(SSP_DR(pl022->virtbase)) & 0xFFU;
754 break;
755 case READING_U16:
756 *(u16 *) (pl022->rx) =
757 (u16) readw(SSP_DR(pl022->virtbase));
758 break;
759 case READING_U32:
760 *(u32 *) (pl022->rx) =
761 readl(SSP_DR(pl022->virtbase));
762 break;
763 }
764 pl022->rx += (pl022->cur_chip->n_bytes);
765 pl022->exp_fifo_level--;
766 }
767 }
768 /*
769 * When we exit here the TX FIFO should be full and the RX FIFO
770 * should be empty
771 */
772}
773
774/**
775 * next_transfer - Move to the Next transfer in the current spi message
776 * @pl022: SSP driver private data structure
777 *
778 * This function moves though the linked list of spi transfers in the
779 * current spi message and returns with the state of current spi
780 * message i.e whether its last transfer is done(STATE_DONE) or
781 * Next transfer is ready(STATE_RUNNING)
782 */
783static void *next_transfer(struct pl022 *pl022)
784{
785 struct spi_message *msg = pl022->cur_msg;
786 struct spi_transfer *trans = pl022->cur_transfer;
787
788 /* Move to next transfer */
789 if (trans->transfer_list.next != &msg->transfers) {
790 pl022->cur_transfer =
791 list_entry(trans->transfer_list.next,
792 struct spi_transfer, transfer_list);
793 return STATE_RUNNING;
794 }
795 return STATE_DONE;
796}
797
798/*
799 * This DMA functionality is only compiled in if we have
800 * access to the generic DMA devices/DMA engine.
801 */
802#ifdef CONFIG_DMA_ENGINE
803static void unmap_free_dma_scatter(struct pl022 *pl022)
804{
805 /* Unmap and free the SG tables */
806 dma_unmap_sg(pl022->dma_tx_channel->device->dev, pl022->sgt_tx.sgl,
807 pl022->sgt_tx.nents, DMA_TO_DEVICE);
808 dma_unmap_sg(pl022->dma_rx_channel->device->dev, pl022->sgt_rx.sgl,
809 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
810 sg_free_table(&pl022->sgt_rx);
811 sg_free_table(&pl022->sgt_tx);
812}
813
814static void dma_callback(void *data)
815{
816 struct pl022 *pl022 = data;
817 struct spi_message *msg = pl022->cur_msg;
818
819 BUG_ON(!pl022->sgt_rx.sgl);
820
821#ifdef VERBOSE_DEBUG
822 /*
823 * Optionally dump out buffers to inspect contents, this is
824 * good if you want to convince yourself that the loopback
825 * read/write contents are the same, when adopting to a new
826 * DMA engine.
827 */
828 {
829 struct scatterlist *sg;
830 unsigned int i;
831
832 dma_sync_sg_for_cpu(&pl022->adev->dev,
833 pl022->sgt_rx.sgl,
834 pl022->sgt_rx.nents,
835 DMA_FROM_DEVICE);
836
837 for_each_sg(pl022->sgt_rx.sgl, sg, pl022->sgt_rx.nents, i) {
838 dev_dbg(&pl022->adev->dev, "SPI RX SG ENTRY: %d", i);
839 print_hex_dump(KERN_ERR, "SPI RX: ",
840 DUMP_PREFIX_OFFSET,
841 16,
842 1,
843 sg_virt(sg),
844 sg_dma_len(sg),
845 1);
846 }
847 for_each_sg(pl022->sgt_tx.sgl, sg, pl022->sgt_tx.nents, i) {
848 dev_dbg(&pl022->adev->dev, "SPI TX SG ENTRY: %d", i);
849 print_hex_dump(KERN_ERR, "SPI TX: ",
850 DUMP_PREFIX_OFFSET,
851 16,
852 1,
853 sg_virt(sg),
854 sg_dma_len(sg),
855 1);
856 }
857 }
858#endif
859
860 unmap_free_dma_scatter(pl022);
861
862 /* Update total bytes transferred */
863 msg->actual_length += pl022->cur_transfer->len;
864 if (pl022->cur_transfer->cs_change)
865 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
866
867 /* Move to next transfer */
868 msg->state = next_transfer(pl022);
869 tasklet_schedule(&pl022->pump_transfers);
870}
871
872static void setup_dma_scatter(struct pl022 *pl022,
873 void *buffer,
874 unsigned int length,
875 struct sg_table *sgtab)
876{
877 struct scatterlist *sg;
878 int bytesleft = length;
879 void *bufp = buffer;
880 int mapbytes;
881 int i;
882
883 if (buffer) {
884 for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
885 /*
886 * If there are less bytes left than what fits
887 * in the current page (plus page alignment offset)
888 * we just feed in this, else we stuff in as much
889 * as we can.
890 */
891 if (bytesleft < (PAGE_SIZE - offset_in_page(bufp)))
892 mapbytes = bytesleft;
893 else
894 mapbytes = PAGE_SIZE - offset_in_page(bufp);
895 sg_set_page(sg, virt_to_page(bufp),
896 mapbytes, offset_in_page(bufp));
897 bufp += mapbytes;
898 bytesleft -= mapbytes;
899 dev_dbg(&pl022->adev->dev,
900 "set RX/TX target page @ %p, %d bytes, %d left\n",
901 bufp, mapbytes, bytesleft);
902 }
903 } else {
904 /* Map the dummy buffer on every page */
905 for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
906 if (bytesleft < PAGE_SIZE)
907 mapbytes = bytesleft;
908 else
909 mapbytes = PAGE_SIZE;
910 sg_set_page(sg, virt_to_page(pl022->dummypage),
911 mapbytes, 0);
912 bytesleft -= mapbytes;
913 dev_dbg(&pl022->adev->dev,
914 "set RX/TX to dummy page %d bytes, %d left\n",
915 mapbytes, bytesleft);
916
917 }
918 }
919 BUG_ON(bytesleft);
920}
921
922/**
923 * configure_dma - configures the channels for the next transfer
924 * @pl022: SSP driver's private data structure
925 */
926static int configure_dma(struct pl022 *pl022)
927{
928 struct dma_slave_config rx_conf = {
929 .src_addr = SSP_DR(pl022->phybase),
930 .direction = DMA_DEV_TO_MEM,
931 .device_fc = false,
932 };
933 struct dma_slave_config tx_conf = {
934 .dst_addr = SSP_DR(pl022->phybase),
935 .direction = DMA_MEM_TO_DEV,
936 .device_fc = false,
937 };
938 unsigned int pages;
939 int ret;
940 int rx_sglen, tx_sglen;
941 struct dma_chan *rxchan = pl022->dma_rx_channel;
942 struct dma_chan *txchan = pl022->dma_tx_channel;
943 struct dma_async_tx_descriptor *rxdesc;
944 struct dma_async_tx_descriptor *txdesc;
945
946 /* Check that the channels are available */
947 if (!rxchan || !txchan)
948 return -ENODEV;
949
950 /*
951 * If supplied, the DMA burstsize should equal the FIFO trigger level.
952 * Notice that the DMA engine uses one-to-one mapping. Since we can
953 * not trigger on 2 elements this needs explicit mapping rather than
954 * calculation.
955 */
956 switch (pl022->rx_lev_trig) {
957 case SSP_RX_1_OR_MORE_ELEM:
958 rx_conf.src_maxburst = 1;
959 break;
960 case SSP_RX_4_OR_MORE_ELEM:
961 rx_conf.src_maxburst = 4;
962 break;
963 case SSP_RX_8_OR_MORE_ELEM:
964 rx_conf.src_maxburst = 8;
965 break;
966 case SSP_RX_16_OR_MORE_ELEM:
967 rx_conf.src_maxburst = 16;
968 break;
969 case SSP_RX_32_OR_MORE_ELEM:
970 rx_conf.src_maxburst = 32;
971 break;
972 default:
973 rx_conf.src_maxburst = pl022->vendor->fifodepth >> 1;
974 break;
975 }
976
977 switch (pl022->tx_lev_trig) {
978 case SSP_TX_1_OR_MORE_EMPTY_LOC:
979 tx_conf.dst_maxburst = 1;
980 break;
981 case SSP_TX_4_OR_MORE_EMPTY_LOC:
982 tx_conf.dst_maxburst = 4;
983 break;
984 case SSP_TX_8_OR_MORE_EMPTY_LOC:
985 tx_conf.dst_maxburst = 8;
986 break;
987 case SSP_TX_16_OR_MORE_EMPTY_LOC:
988 tx_conf.dst_maxburst = 16;
989 break;
990 case SSP_TX_32_OR_MORE_EMPTY_LOC:
991 tx_conf.dst_maxburst = 32;
992 break;
993 default:
994 tx_conf.dst_maxburst = pl022->vendor->fifodepth >> 1;
995 break;
996 }
997
998 switch (pl022->read) {
999 case READING_NULL:
1000 /* Use the same as for writing */
1001 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
1002 break;
1003 case READING_U8:
1004 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1005 break;
1006 case READING_U16:
1007 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
1008 break;
1009 case READING_U32:
1010 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1011 break;
1012 }
1013
1014 switch (pl022->write) {
1015 case WRITING_NULL:
1016 /* Use the same as for reading */
1017 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
1018 break;
1019 case WRITING_U8:
1020 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1021 break;
1022 case WRITING_U16:
1023 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
1024 break;
1025 case WRITING_U32:
1026 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1027 break;
1028 }
1029
1030 /* SPI pecularity: we need to read and write the same width */
1031 if (rx_conf.src_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
1032 rx_conf.src_addr_width = tx_conf.dst_addr_width;
1033 if (tx_conf.dst_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
1034 tx_conf.dst_addr_width = rx_conf.src_addr_width;
1035 BUG_ON(rx_conf.src_addr_width != tx_conf.dst_addr_width);
1036
1037 dmaengine_slave_config(rxchan, &rx_conf);
1038 dmaengine_slave_config(txchan, &tx_conf);
1039
1040 /* Create sglists for the transfers */
1041 pages = DIV_ROUND_UP(pl022->cur_transfer->len, PAGE_SIZE);
1042 dev_dbg(&pl022->adev->dev, "using %d pages for transfer\n", pages);
1043
1044 ret = sg_alloc_table(&pl022->sgt_rx, pages, GFP_ATOMIC);
1045 if (ret)
1046 goto err_alloc_rx_sg;
1047
1048 ret = sg_alloc_table(&pl022->sgt_tx, pages, GFP_ATOMIC);
1049 if (ret)
1050 goto err_alloc_tx_sg;
1051
1052 /* Fill in the scatterlists for the RX+TX buffers */
1053 setup_dma_scatter(pl022, pl022->rx,
1054 pl022->cur_transfer->len, &pl022->sgt_rx);
1055 setup_dma_scatter(pl022, pl022->tx,
1056 pl022->cur_transfer->len, &pl022->sgt_tx);
1057
1058 /* Map DMA buffers */
1059 rx_sglen = dma_map_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
1060 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
1061 if (!rx_sglen)
1062 goto err_rx_sgmap;
1063
1064 tx_sglen = dma_map_sg(txchan->device->dev, pl022->sgt_tx.sgl,
1065 pl022->sgt_tx.nents, DMA_TO_DEVICE);
1066 if (!tx_sglen)
1067 goto err_tx_sgmap;
1068
1069 /* Send both scatterlists */
1070 rxdesc = dmaengine_prep_slave_sg(rxchan,
1071 pl022->sgt_rx.sgl,
1072 rx_sglen,
1073 DMA_DEV_TO_MEM,
1074 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1075 if (!rxdesc)
1076 goto err_rxdesc;
1077
1078 txdesc = dmaengine_prep_slave_sg(txchan,
1079 pl022->sgt_tx.sgl,
1080 tx_sglen,
1081 DMA_MEM_TO_DEV,
1082 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1083 if (!txdesc)
1084 goto err_txdesc;
1085
1086 /* Put the callback on the RX transfer only, that should finish last */
1087 rxdesc->callback = dma_callback;
1088 rxdesc->callback_param = pl022;
1089
1090 /* Submit and fire RX and TX with TX last so we're ready to read! */
1091 dmaengine_submit(rxdesc);
1092 dmaengine_submit(txdesc);
1093 dma_async_issue_pending(rxchan);
1094 dma_async_issue_pending(txchan);
1095 pl022->dma_running = true;
1096
1097 return 0;
1098
1099err_txdesc:
1100 dmaengine_terminate_all(txchan);
1101err_rxdesc:
1102 dmaengine_terminate_all(rxchan);
1103 dma_unmap_sg(txchan->device->dev, pl022->sgt_tx.sgl,
1104 pl022->sgt_tx.nents, DMA_TO_DEVICE);
1105err_tx_sgmap:
1106 dma_unmap_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
1107 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
1108err_rx_sgmap:
1109 sg_free_table(&pl022->sgt_tx);
1110err_alloc_tx_sg:
1111 sg_free_table(&pl022->sgt_rx);
1112err_alloc_rx_sg:
1113 return -ENOMEM;
1114}
1115
1116static int pl022_dma_probe(struct pl022 *pl022)
1117{
1118 dma_cap_mask_t mask;
1119
1120 /* Try to acquire a generic DMA engine slave channel */
1121 dma_cap_zero(mask);
1122 dma_cap_set(DMA_SLAVE, mask);
1123 /*
1124 * We need both RX and TX channels to do DMA, else do none
1125 * of them.
1126 */
1127 pl022->dma_rx_channel = dma_request_channel(mask,
1128 pl022->master_info->dma_filter,
1129 pl022->master_info->dma_rx_param);
1130 if (!pl022->dma_rx_channel) {
1131 dev_dbg(&pl022->adev->dev, "no RX DMA channel!\n");
1132 goto err_no_rxchan;
1133 }
1134
1135 pl022->dma_tx_channel = dma_request_channel(mask,
1136 pl022->master_info->dma_filter,
1137 pl022->master_info->dma_tx_param);
1138 if (!pl022->dma_tx_channel) {
1139 dev_dbg(&pl022->adev->dev, "no TX DMA channel!\n");
1140 goto err_no_txchan;
1141 }
1142
1143 pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
1144 if (!pl022->dummypage)
1145 goto err_no_dummypage;
1146
1147 dev_info(&pl022->adev->dev, "setup for DMA on RX %s, TX %s\n",
1148 dma_chan_name(pl022->dma_rx_channel),
1149 dma_chan_name(pl022->dma_tx_channel));
1150
1151 return 0;
1152
1153err_no_dummypage:
1154 dma_release_channel(pl022->dma_tx_channel);
1155err_no_txchan:
1156 dma_release_channel(pl022->dma_rx_channel);
1157 pl022->dma_rx_channel = NULL;
1158err_no_rxchan:
1159 dev_err(&pl022->adev->dev,
1160 "Failed to work in dma mode, work without dma!\n");
1161 return -ENODEV;
1162}
1163
1164static int pl022_dma_autoprobe(struct pl022 *pl022)
1165{
1166 struct device *dev = &pl022->adev->dev;
1167 struct dma_chan *chan;
1168 int err;
1169
1170 /* automatically configure DMA channels from platform, normally using DT */
1171 chan = dma_request_slave_channel_reason(dev, "rx");
1172 if (IS_ERR(chan)) {
1173 err = PTR_ERR(chan);
1174 goto err_no_rxchan;
1175 }
1176
1177 pl022->dma_rx_channel = chan;
1178
1179 chan = dma_request_slave_channel_reason(dev, "tx");
1180 if (IS_ERR(chan)) {
1181 err = PTR_ERR(chan);
1182 goto err_no_txchan;
1183 }
1184
1185 pl022->dma_tx_channel = chan;
1186
1187 pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
1188 if (!pl022->dummypage) {
1189 err = -ENOMEM;
1190 goto err_no_dummypage;
1191 }
1192
1193 return 0;
1194
1195err_no_dummypage:
1196 dma_release_channel(pl022->dma_tx_channel);
1197 pl022->dma_tx_channel = NULL;
1198err_no_txchan:
1199 dma_release_channel(pl022->dma_rx_channel);
1200 pl022->dma_rx_channel = NULL;
1201err_no_rxchan:
1202 return err;
1203}
1204
1205static void terminate_dma(struct pl022 *pl022)
1206{
1207 struct dma_chan *rxchan = pl022->dma_rx_channel;
1208 struct dma_chan *txchan = pl022->dma_tx_channel;
1209
1210 dmaengine_terminate_all(rxchan);
1211 dmaengine_terminate_all(txchan);
1212 unmap_free_dma_scatter(pl022);
1213 pl022->dma_running = false;
1214}
1215
1216static void pl022_dma_remove(struct pl022 *pl022)
1217{
1218 if (pl022->dma_running)
1219 terminate_dma(pl022);
1220 if (pl022->dma_tx_channel)
1221 dma_release_channel(pl022->dma_tx_channel);
1222 if (pl022->dma_rx_channel)
1223 dma_release_channel(pl022->dma_rx_channel);
1224 kfree(pl022->dummypage);
1225}
1226
1227#else
1228static inline int configure_dma(struct pl022 *pl022)
1229{
1230 return -ENODEV;
1231}
1232
1233static inline int pl022_dma_autoprobe(struct pl022 *pl022)
1234{
1235 return 0;
1236}
1237
1238static inline int pl022_dma_probe(struct pl022 *pl022)
1239{
1240 return 0;
1241}
1242
1243static inline void pl022_dma_remove(struct pl022 *pl022)
1244{
1245}
1246#endif
1247
1248/**
1249 * pl022_interrupt_handler - Interrupt handler for SSP controller
1250 *
1251 * This function handles interrupts generated for an interrupt based transfer.
1252 * If a receive overrun (ROR) interrupt is there then we disable SSP, flag the
1253 * current message's state as STATE_ERROR and schedule the tasklet
1254 * pump_transfers which will do the postprocessing of the current message by
1255 * calling giveback(). Otherwise it reads data from RX FIFO till there is no
1256 * more data, and writes data in TX FIFO till it is not full. If we complete
1257 * the transfer we move to the next transfer and schedule the tasklet.
1258 */
1259static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id)
1260{
1261 struct pl022 *pl022 = dev_id;
1262 struct spi_message *msg = pl022->cur_msg;
1263 u16 irq_status = 0;
1264
1265 if (unlikely(!msg)) {
1266 dev_err(&pl022->adev->dev,
1267 "bad message state in interrupt handler");
1268 /* Never fail */
1269 return IRQ_HANDLED;
1270 }
1271
1272 /* Read the Interrupt Status Register */
1273 irq_status = readw(SSP_MIS(pl022->virtbase));
1274
1275 if (unlikely(!irq_status))
1276 return IRQ_NONE;
1277
1278 /*
1279 * This handles the FIFO interrupts, the timeout
1280 * interrupts are flatly ignored, they cannot be
1281 * trusted.
1282 */
1283 if (unlikely(irq_status & SSP_MIS_MASK_RORMIS)) {
1284 /*
1285 * Overrun interrupt - bail out since our Data has been
1286 * corrupted
1287 */
1288 dev_err(&pl022->adev->dev, "FIFO overrun\n");
1289 if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RFF)
1290 dev_err(&pl022->adev->dev,
1291 "RXFIFO is full\n");
1292
1293 /*
1294 * Disable and clear interrupts, disable SSP,
1295 * mark message with bad status so it can be
1296 * retried.
1297 */
1298 writew(DISABLE_ALL_INTERRUPTS,
1299 SSP_IMSC(pl022->virtbase));
1300 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1301 writew((readw(SSP_CR1(pl022->virtbase)) &
1302 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1303 msg->state = STATE_ERROR;
1304
1305 /* Schedule message queue handler */
1306 tasklet_schedule(&pl022->pump_transfers);
1307 return IRQ_HANDLED;
1308 }
1309
1310 readwriter(pl022);
1311
1312 if (pl022->tx == pl022->tx_end) {
1313 /* Disable Transmit interrupt, enable receive interrupt */
1314 writew((readw(SSP_IMSC(pl022->virtbase)) &
1315 ~SSP_IMSC_MASK_TXIM) | SSP_IMSC_MASK_RXIM,
1316 SSP_IMSC(pl022->virtbase));
1317 }
1318
1319 /*
1320 * Since all transactions must write as much as shall be read,
1321 * we can conclude the entire transaction once RX is complete.
1322 * At this point, all TX will always be finished.
1323 */
1324 if (pl022->rx >= pl022->rx_end) {
1325 writew(DISABLE_ALL_INTERRUPTS,
1326 SSP_IMSC(pl022->virtbase));
1327 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1328 if (unlikely(pl022->rx > pl022->rx_end)) {
1329 dev_warn(&pl022->adev->dev, "read %u surplus "
1330 "bytes (did you request an odd "
1331 "number of bytes on a 16bit bus?)\n",
1332 (u32) (pl022->rx - pl022->rx_end));
1333 }
1334 /* Update total bytes transferred */
1335 msg->actual_length += pl022->cur_transfer->len;
1336 if (pl022->cur_transfer->cs_change)
1337 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
1338 /* Move to next transfer */
1339 msg->state = next_transfer(pl022);
1340 tasklet_schedule(&pl022->pump_transfers);
1341 return IRQ_HANDLED;
1342 }
1343
1344 return IRQ_HANDLED;
1345}
1346
1347/**
1348 * This sets up the pointers to memory for the next message to
1349 * send out on the SPI bus.
1350 */
1351static int set_up_next_transfer(struct pl022 *pl022,
1352 struct spi_transfer *transfer)
1353{
1354 int residue;
1355
1356 /* Sanity check the message for this bus width */
1357 residue = pl022->cur_transfer->len % pl022->cur_chip->n_bytes;
1358 if (unlikely(residue != 0)) {
1359 dev_err(&pl022->adev->dev,
1360 "message of %u bytes to transmit but the current "
1361 "chip bus has a data width of %u bytes!\n",
1362 pl022->cur_transfer->len,
1363 pl022->cur_chip->n_bytes);
1364 dev_err(&pl022->adev->dev, "skipping this message\n");
1365 return -EIO;
1366 }
1367 pl022->tx = (void *)transfer->tx_buf;
1368 pl022->tx_end = pl022->tx + pl022->cur_transfer->len;
1369 pl022->rx = (void *)transfer->rx_buf;
1370 pl022->rx_end = pl022->rx + pl022->cur_transfer->len;
1371 pl022->write =
1372 pl022->tx ? pl022->cur_chip->write : WRITING_NULL;
1373 pl022->read = pl022->rx ? pl022->cur_chip->read : READING_NULL;
1374 return 0;
1375}
1376
1377/**
1378 * pump_transfers - Tasklet function which schedules next transfer
1379 * when running in interrupt or DMA transfer mode.
1380 * @data: SSP driver private data structure
1381 *
1382 */
1383static void pump_transfers(unsigned long data)
1384{
1385 struct pl022 *pl022 = (struct pl022 *) data;
1386 struct spi_message *message = NULL;
1387 struct spi_transfer *transfer = NULL;
1388 struct spi_transfer *previous = NULL;
1389
1390 /* Get current state information */
1391 message = pl022->cur_msg;
1392 transfer = pl022->cur_transfer;
1393
1394 /* Handle for abort */
1395 if (message->state == STATE_ERROR) {
1396 message->status = -EIO;
1397 giveback(pl022);
1398 return;
1399 }
1400
1401 /* Handle end of message */
1402 if (message->state == STATE_DONE) {
1403 message->status = 0;
1404 giveback(pl022);
1405 return;
1406 }
1407
1408 /* Delay if requested at end of transfer before CS change */
1409 if (message->state == STATE_RUNNING) {
1410 previous = list_entry(transfer->transfer_list.prev,
1411 struct spi_transfer,
1412 transfer_list);
1413 if (previous->delay_usecs)
1414 /*
1415 * FIXME: This runs in interrupt context.
1416 * Is this really smart?
1417 */
1418 udelay(previous->delay_usecs);
1419
1420 /* Reselect chip select only if cs_change was requested */
1421 if (previous->cs_change)
1422 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1423 } else {
1424 /* STATE_START */
1425 message->state = STATE_RUNNING;
1426 }
1427
1428 if (set_up_next_transfer(pl022, transfer)) {
1429 message->state = STATE_ERROR;
1430 message->status = -EIO;
1431 giveback(pl022);
1432 return;
1433 }
1434 /* Flush the FIFOs and let's go! */
1435 flush(pl022);
1436
1437 if (pl022->cur_chip->enable_dma) {
1438 if (configure_dma(pl022)) {
1439 dev_dbg(&pl022->adev->dev,
1440 "configuration of DMA failed, fall back to interrupt mode\n");
1441 goto err_config_dma;
1442 }
1443 return;
1444 }
1445
1446err_config_dma:
1447 /* enable all interrupts except RX */
1448 writew(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM, SSP_IMSC(pl022->virtbase));
1449}
1450
1451static void do_interrupt_dma_transfer(struct pl022 *pl022)
1452{
1453 /*
1454 * Default is to enable all interrupts except RX -
1455 * this will be enabled once TX is complete
1456 */
1457 u32 irqflags = (u32)(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM);
1458
1459 /* Enable target chip, if not already active */
1460 if (!pl022->next_msg_cs_active)
1461 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1462
1463 if (set_up_next_transfer(pl022, pl022->cur_transfer)) {
1464 /* Error path */
1465 pl022->cur_msg->state = STATE_ERROR;
1466 pl022->cur_msg->status = -EIO;
1467 giveback(pl022);
1468 return;
1469 }
1470 /* If we're using DMA, set up DMA here */
1471 if (pl022->cur_chip->enable_dma) {
1472 /* Configure DMA transfer */
1473 if (configure_dma(pl022)) {
1474 dev_dbg(&pl022->adev->dev,
1475 "configuration of DMA failed, fall back to interrupt mode\n");
1476 goto err_config_dma;
1477 }
1478 /* Disable interrupts in DMA mode, IRQ from DMA controller */
1479 irqflags = DISABLE_ALL_INTERRUPTS;
1480 }
1481err_config_dma:
1482 /* Enable SSP, turn on interrupts */
1483 writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1484 SSP_CR1(pl022->virtbase));
1485 writew(irqflags, SSP_IMSC(pl022->virtbase));
1486}
1487
1488static void do_polling_transfer(struct pl022 *pl022)
1489{
1490 struct spi_message *message = NULL;
1491 struct spi_transfer *transfer = NULL;
1492 struct spi_transfer *previous = NULL;
1493 struct chip_data *chip;
1494 unsigned long time, timeout;
1495
1496 chip = pl022->cur_chip;
1497 message = pl022->cur_msg;
1498
1499 while (message->state != STATE_DONE) {
1500 /* Handle for abort */
1501 if (message->state == STATE_ERROR)
1502 break;
1503 transfer = pl022->cur_transfer;
1504
1505 /* Delay if requested at end of transfer */
1506 if (message->state == STATE_RUNNING) {
1507 previous =
1508 list_entry(transfer->transfer_list.prev,
1509 struct spi_transfer, transfer_list);
1510 if (previous->delay_usecs)
1511 udelay(previous->delay_usecs);
1512 if (previous->cs_change)
1513 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1514 } else {
1515 /* STATE_START */
1516 message->state = STATE_RUNNING;
1517 if (!pl022->next_msg_cs_active)
1518 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1519 }
1520
1521 /* Configuration Changing Per Transfer */
1522 if (set_up_next_transfer(pl022, transfer)) {
1523 /* Error path */
1524 message->state = STATE_ERROR;
1525 break;
1526 }
1527 /* Flush FIFOs and enable SSP */
1528 flush(pl022);
1529 writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1530 SSP_CR1(pl022->virtbase));
1531
1532 dev_dbg(&pl022->adev->dev, "polling transfer ongoing ...\n");
1533
1534 timeout = jiffies + msecs_to_jiffies(SPI_POLLING_TIMEOUT);
1535 while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end) {
1536 time = jiffies;
1537 readwriter(pl022);
1538 if (time_after(time, timeout)) {
1539 dev_warn(&pl022->adev->dev,
1540 "%s: timeout!\n", __func__);
1541 message->state = STATE_ERROR;
1542 goto out;
1543 }
1544 cpu_relax();
1545 }
1546
1547 /* Update total byte transferred */
1548 message->actual_length += pl022->cur_transfer->len;
1549 if (pl022->cur_transfer->cs_change)
1550 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
1551 /* Move to next transfer */
1552 message->state = next_transfer(pl022);
1553 }
1554out:
1555 /* Handle end of message */
1556 if (message->state == STATE_DONE)
1557 message->status = 0;
1558 else
1559 message->status = -EIO;
1560
1561 giveback(pl022);
1562 return;
1563}
1564
1565static int pl022_transfer_one_message(struct spi_master *master,
1566 struct spi_message *msg)
1567{
1568 struct pl022 *pl022 = spi_master_get_devdata(master);
1569
1570 /* Initial message state */
1571 pl022->cur_msg = msg;
1572 msg->state = STATE_START;
1573
1574 pl022->cur_transfer = list_entry(msg->transfers.next,
1575 struct spi_transfer, transfer_list);
1576
1577 /* Setup the SPI using the per chip configuration */
1578 pl022->cur_chip = spi_get_ctldata(msg->spi);
1579 pl022->cur_cs = pl022->chipselects[msg->spi->chip_select];
1580
1581 restore_state(pl022);
1582 flush(pl022);
1583
1584 if (pl022->cur_chip->xfer_type == POLLING_TRANSFER)
1585 do_polling_transfer(pl022);
1586 else
1587 do_interrupt_dma_transfer(pl022);
1588
1589 return 0;
1590}
1591
1592static int pl022_unprepare_transfer_hardware(struct spi_master *master)
1593{
1594 struct pl022 *pl022 = spi_master_get_devdata(master);
1595
1596 /* nothing more to do - disable spi/ssp and power off */
1597 writew((readw(SSP_CR1(pl022->virtbase)) &
1598 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1599
1600 return 0;
1601}
1602
1603static int verify_controller_parameters(struct pl022 *pl022,
1604 struct pl022_config_chip const *chip_info)
1605{
1606 if ((chip_info->iface < SSP_INTERFACE_MOTOROLA_SPI)
1607 || (chip_info->iface > SSP_INTERFACE_UNIDIRECTIONAL)) {
1608 dev_err(&pl022->adev->dev,
1609 "interface is configured incorrectly\n");
1610 return -EINVAL;
1611 }
1612 if ((chip_info->iface == SSP_INTERFACE_UNIDIRECTIONAL) &&
1613 (!pl022->vendor->unidir)) {
1614 dev_err(&pl022->adev->dev,
1615 "unidirectional mode not supported in this "
1616 "hardware version\n");
1617 return -EINVAL;
1618 }
1619 if ((chip_info->hierarchy != SSP_MASTER)
1620 && (chip_info->hierarchy != SSP_SLAVE)) {
1621 dev_err(&pl022->adev->dev,
1622 "hierarchy is configured incorrectly\n");
1623 return -EINVAL;
1624 }
1625 if ((chip_info->com_mode != INTERRUPT_TRANSFER)
1626 && (chip_info->com_mode != DMA_TRANSFER)
1627 && (chip_info->com_mode != POLLING_TRANSFER)) {
1628 dev_err(&pl022->adev->dev,
1629 "Communication mode is configured incorrectly\n");
1630 return -EINVAL;
1631 }
1632 switch (chip_info->rx_lev_trig) {
1633 case SSP_RX_1_OR_MORE_ELEM:
1634 case SSP_RX_4_OR_MORE_ELEM:
1635 case SSP_RX_8_OR_MORE_ELEM:
1636 /* These are always OK, all variants can handle this */
1637 break;
1638 case SSP_RX_16_OR_MORE_ELEM:
1639 if (pl022->vendor->fifodepth < 16) {
1640 dev_err(&pl022->adev->dev,
1641 "RX FIFO Trigger Level is configured incorrectly\n");
1642 return -EINVAL;
1643 }
1644 break;
1645 case SSP_RX_32_OR_MORE_ELEM:
1646 if (pl022->vendor->fifodepth < 32) {
1647 dev_err(&pl022->adev->dev,
1648 "RX FIFO Trigger Level is configured incorrectly\n");
1649 return -EINVAL;
1650 }
1651 break;
1652 default:
1653 dev_err(&pl022->adev->dev,
1654 "RX FIFO Trigger Level is configured incorrectly\n");
1655 return -EINVAL;
1656 }
1657 switch (chip_info->tx_lev_trig) {
1658 case SSP_TX_1_OR_MORE_EMPTY_LOC:
1659 case SSP_TX_4_OR_MORE_EMPTY_LOC:
1660 case SSP_TX_8_OR_MORE_EMPTY_LOC:
1661 /* These are always OK, all variants can handle this */
1662 break;
1663 case SSP_TX_16_OR_MORE_EMPTY_LOC:
1664 if (pl022->vendor->fifodepth < 16) {
1665 dev_err(&pl022->adev->dev,
1666 "TX FIFO Trigger Level is configured incorrectly\n");
1667 return -EINVAL;
1668 }
1669 break;
1670 case SSP_TX_32_OR_MORE_EMPTY_LOC:
1671 if (pl022->vendor->fifodepth < 32) {
1672 dev_err(&pl022->adev->dev,
1673 "TX FIFO Trigger Level is configured incorrectly\n");
1674 return -EINVAL;
1675 }
1676 break;
1677 default:
1678 dev_err(&pl022->adev->dev,
1679 "TX FIFO Trigger Level is configured incorrectly\n");
1680 return -EINVAL;
1681 }
1682 if (chip_info->iface == SSP_INTERFACE_NATIONAL_MICROWIRE) {
1683 if ((chip_info->ctrl_len < SSP_BITS_4)
1684 || (chip_info->ctrl_len > SSP_BITS_32)) {
1685 dev_err(&pl022->adev->dev,
1686 "CTRL LEN is configured incorrectly\n");
1687 return -EINVAL;
1688 }
1689 if ((chip_info->wait_state != SSP_MWIRE_WAIT_ZERO)
1690 && (chip_info->wait_state != SSP_MWIRE_WAIT_ONE)) {
1691 dev_err(&pl022->adev->dev,
1692 "Wait State is configured incorrectly\n");
1693 return -EINVAL;
1694 }
1695 /* Half duplex is only available in the ST Micro version */
1696 if (pl022->vendor->extended_cr) {
1697 if ((chip_info->duplex !=
1698 SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
1699 && (chip_info->duplex !=
1700 SSP_MICROWIRE_CHANNEL_HALF_DUPLEX)) {
1701 dev_err(&pl022->adev->dev,
1702 "Microwire duplex mode is configured incorrectly\n");
1703 return -EINVAL;
1704 }
1705 } else {
1706 if (chip_info->duplex != SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
1707 dev_err(&pl022->adev->dev,
1708 "Microwire half duplex mode requested,"
1709 " but this is only available in the"
1710 " ST version of PL022\n");
1711 return -EINVAL;
1712 }
1713 }
1714 return 0;
1715}
1716
1717static inline u32 spi_rate(u32 rate, u16 cpsdvsr, u16 scr)
1718{
1719 return rate / (cpsdvsr * (1 + scr));
1720}
1721
1722static int calculate_effective_freq(struct pl022 *pl022, int freq, struct
1723 ssp_clock_params * clk_freq)
1724{
1725 /* Lets calculate the frequency parameters */
1726 u16 cpsdvsr = CPSDVR_MIN, scr = SCR_MIN;
1727 u32 rate, max_tclk, min_tclk, best_freq = 0, best_cpsdvsr = 0,
1728 best_scr = 0, tmp, found = 0;
1729
1730 rate = clk_get_rate(pl022->clk);
1731 /* cpsdvscr = 2 & scr 0 */
1732 max_tclk = spi_rate(rate, CPSDVR_MIN, SCR_MIN);
1733 /* cpsdvsr = 254 & scr = 255 */
1734 min_tclk = spi_rate(rate, CPSDVR_MAX, SCR_MAX);
1735
1736 if (freq > max_tclk)
1737 dev_warn(&pl022->adev->dev,
1738 "Max speed that can be programmed is %d Hz, you requested %d\n",
1739 max_tclk, freq);
1740
1741 if (freq < min_tclk) {
1742 dev_err(&pl022->adev->dev,
1743 "Requested frequency: %d Hz is less than minimum possible %d Hz\n",
1744 freq, min_tclk);
1745 return -EINVAL;
1746 }
1747
1748 /*
1749 * best_freq will give closest possible available rate (<= requested
1750 * freq) for all values of scr & cpsdvsr.
1751 */
1752 while ((cpsdvsr <= CPSDVR_MAX) && !found) {
1753 while (scr <= SCR_MAX) {
1754 tmp = spi_rate(rate, cpsdvsr, scr);
1755
1756 if (tmp > freq) {
1757 /* we need lower freq */
1758 scr++;
1759 continue;
1760 }
1761
1762 /*
1763 * If found exact value, mark found and break.
1764 * If found more closer value, update and break.
1765 */
1766 if (tmp > best_freq) {
1767 best_freq = tmp;
1768 best_cpsdvsr = cpsdvsr;
1769 best_scr = scr;
1770
1771 if (tmp == freq)
1772 found = 1;
1773 }
1774 /*
1775 * increased scr will give lower rates, which are not
1776 * required
1777 */
1778 break;
1779 }
1780 cpsdvsr += 2;
1781 scr = SCR_MIN;
1782 }
1783
1784 WARN(!best_freq, "pl022: Matching cpsdvsr and scr not found for %d Hz rate \n",
1785 freq);
1786
1787 clk_freq->cpsdvsr = (u8) (best_cpsdvsr & 0xFF);
1788 clk_freq->scr = (u8) (best_scr & 0xFF);
1789 dev_dbg(&pl022->adev->dev,
1790 "SSP Target Frequency is: %u, Effective Frequency is %u\n",
1791 freq, best_freq);
1792 dev_dbg(&pl022->adev->dev, "SSP cpsdvsr = %d, scr = %d\n",
1793 clk_freq->cpsdvsr, clk_freq->scr);
1794
1795 return 0;
1796}
1797
1798/*
1799 * A piece of default chip info unless the platform
1800 * supplies it.
1801 */
1802static const struct pl022_config_chip pl022_default_chip_info = {
1803 .com_mode = POLLING_TRANSFER,
1804 .iface = SSP_INTERFACE_MOTOROLA_SPI,
1805 .hierarchy = SSP_SLAVE,
1806 .slave_tx_disable = DO_NOT_DRIVE_TX,
1807 .rx_lev_trig = SSP_RX_1_OR_MORE_ELEM,
1808 .tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC,
1809 .ctrl_len = SSP_BITS_8,
1810 .wait_state = SSP_MWIRE_WAIT_ZERO,
1811 .duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX,
1812 .cs_control = null_cs_control,
1813};
1814
1815/**
1816 * pl022_setup - setup function registered to SPI master framework
1817 * @spi: spi device which is requesting setup
1818 *
1819 * This function is registered to the SPI framework for this SPI master
1820 * controller. If it is the first time when setup is called by this device,
1821 * this function will initialize the runtime state for this chip and save
1822 * the same in the device structure. Else it will update the runtime info
1823 * with the updated chip info. Nothing is really being written to the
1824 * controller hardware here, that is not done until the actual transfer
1825 * commence.
1826 */
1827static int pl022_setup(struct spi_device *spi)
1828{
1829 struct pl022_config_chip const *chip_info;
1830 struct pl022_config_chip chip_info_dt;
1831 struct chip_data *chip;
1832 struct ssp_clock_params clk_freq = { .cpsdvsr = 0, .scr = 0};
1833 int status = 0;
1834 struct pl022 *pl022 = spi_master_get_devdata(spi->master);
1835 unsigned int bits = spi->bits_per_word;
1836 u32 tmp;
1837 struct device_node *np = spi->dev.of_node;
1838
1839 if (!spi->max_speed_hz)
1840 return -EINVAL;
1841
1842 /* Get controller_state if one is supplied */
1843 chip = spi_get_ctldata(spi);
1844
1845 if (chip == NULL) {
1846 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
1847 if (!chip)
1848 return -ENOMEM;
1849 dev_dbg(&spi->dev,
1850 "allocated memory for controller's runtime state\n");
1851 }
1852
1853 /* Get controller data if one is supplied */
1854 chip_info = spi->controller_data;
1855
1856 if (chip_info == NULL) {
1857 if (np) {
1858 chip_info_dt = pl022_default_chip_info;
1859
1860 chip_info_dt.hierarchy = SSP_MASTER;
1861 of_property_read_u32(np, "pl022,interface",
1862 &chip_info_dt.iface);
1863 of_property_read_u32(np, "pl022,com-mode",
1864 &chip_info_dt.com_mode);
1865 of_property_read_u32(np, "pl022,rx-level-trig",
1866 &chip_info_dt.rx_lev_trig);
1867 of_property_read_u32(np, "pl022,tx-level-trig",
1868 &chip_info_dt.tx_lev_trig);
1869 of_property_read_u32(np, "pl022,ctrl-len",
1870 &chip_info_dt.ctrl_len);
1871 of_property_read_u32(np, "pl022,wait-state",
1872 &chip_info_dt.wait_state);
1873 of_property_read_u32(np, "pl022,duplex",
1874 &chip_info_dt.duplex);
1875
1876 chip_info = &chip_info_dt;
1877 } else {
1878 chip_info = &pl022_default_chip_info;
1879 /* spi_board_info.controller_data not is supplied */
1880 dev_dbg(&spi->dev,
1881 "using default controller_data settings\n");
1882 }
1883 } else
1884 dev_dbg(&spi->dev,
1885 "using user supplied controller_data settings\n");
1886
1887 /*
1888 * We can override with custom divisors, else we use the board
1889 * frequency setting
1890 */
1891 if ((0 == chip_info->clk_freq.cpsdvsr)
1892 && (0 == chip_info->clk_freq.scr)) {
1893 status = calculate_effective_freq(pl022,
1894 spi->max_speed_hz,
1895 &clk_freq);
1896 if (status < 0)
1897 goto err_config_params;
1898 } else {
1899 memcpy(&clk_freq, &chip_info->clk_freq, sizeof(clk_freq));
1900 if ((clk_freq.cpsdvsr % 2) != 0)
1901 clk_freq.cpsdvsr =
1902 clk_freq.cpsdvsr - 1;
1903 }
1904 if ((clk_freq.cpsdvsr < CPSDVR_MIN)
1905 || (clk_freq.cpsdvsr > CPSDVR_MAX)) {
1906 status = -EINVAL;
1907 dev_err(&spi->dev,
1908 "cpsdvsr is configured incorrectly\n");
1909 goto err_config_params;
1910 }
1911
1912 status = verify_controller_parameters(pl022, chip_info);
1913 if (status) {
1914 dev_err(&spi->dev, "controller data is incorrect");
1915 goto err_config_params;
1916 }
1917
1918 pl022->rx_lev_trig = chip_info->rx_lev_trig;
1919 pl022->tx_lev_trig = chip_info->tx_lev_trig;
1920
1921 /* Now set controller state based on controller data */
1922 chip->xfer_type = chip_info->com_mode;
1923 if (!chip_info->cs_control) {
1924 chip->cs_control = null_cs_control;
1925 if (!gpio_is_valid(pl022->chipselects[spi->chip_select]))
1926 dev_warn(&spi->dev,
1927 "invalid chip select\n");
1928 } else
1929 chip->cs_control = chip_info->cs_control;
1930
1931 /* Check bits per word with vendor specific range */
1932 if ((bits <= 3) || (bits > pl022->vendor->max_bpw)) {
1933 status = -ENOTSUPP;
1934 dev_err(&spi->dev, "illegal data size for this controller!\n");
1935 dev_err(&spi->dev, "This controller can only handle 4 <= n <= %d bit words\n",
1936 pl022->vendor->max_bpw);
1937 goto err_config_params;
1938 } else if (bits <= 8) {
1939 dev_dbg(&spi->dev, "4 <= n <=8 bits per word\n");
1940 chip->n_bytes = 1;
1941 chip->read = READING_U8;
1942 chip->write = WRITING_U8;
1943 } else if (bits <= 16) {
1944 dev_dbg(&spi->dev, "9 <= n <= 16 bits per word\n");
1945 chip->n_bytes = 2;
1946 chip->read = READING_U16;
1947 chip->write = WRITING_U16;
1948 } else {
1949 dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n");
1950 chip->n_bytes = 4;
1951 chip->read = READING_U32;
1952 chip->write = WRITING_U32;
1953 }
1954
1955 /* Now Initialize all register settings required for this chip */
1956 chip->cr0 = 0;
1957 chip->cr1 = 0;
1958 chip->dmacr = 0;
1959 chip->cpsr = 0;
1960 if ((chip_info->com_mode == DMA_TRANSFER)
1961 && ((pl022->master_info)->enable_dma)) {
1962 chip->enable_dma = true;
1963 dev_dbg(&spi->dev, "DMA mode set in controller state\n");
1964 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
1965 SSP_DMACR_MASK_RXDMAE, 0);
1966 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
1967 SSP_DMACR_MASK_TXDMAE, 1);
1968 } else {
1969 chip->enable_dma = false;
1970 dev_dbg(&spi->dev, "DMA mode NOT set in controller state\n");
1971 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
1972 SSP_DMACR_MASK_RXDMAE, 0);
1973 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
1974 SSP_DMACR_MASK_TXDMAE, 1);
1975 }
1976
1977 chip->cpsr = clk_freq.cpsdvsr;
1978
1979 /* Special setup for the ST micro extended control registers */
1980 if (pl022->vendor->extended_cr) {
1981 u32 etx;
1982
1983 if (pl022->vendor->pl023) {
1984 /* These bits are only in the PL023 */
1985 SSP_WRITE_BITS(chip->cr1, chip_info->clkdelay,
1986 SSP_CR1_MASK_FBCLKDEL_ST, 13);
1987 } else {
1988 /* These bits are in the PL022 but not PL023 */
1989 SSP_WRITE_BITS(chip->cr0, chip_info->duplex,
1990 SSP_CR0_MASK_HALFDUP_ST, 5);
1991 SSP_WRITE_BITS(chip->cr0, chip_info->ctrl_len,
1992 SSP_CR0_MASK_CSS_ST, 16);
1993 SSP_WRITE_BITS(chip->cr0, chip_info->iface,
1994 SSP_CR0_MASK_FRF_ST, 21);
1995 SSP_WRITE_BITS(chip->cr1, chip_info->wait_state,
1996 SSP_CR1_MASK_MWAIT_ST, 6);
1997 }
1998 SSP_WRITE_BITS(chip->cr0, bits - 1,
1999 SSP_CR0_MASK_DSS_ST, 0);
2000
2001 if (spi->mode & SPI_LSB_FIRST) {
2002 tmp = SSP_RX_LSB;
2003 etx = SSP_TX_LSB;
2004 } else {
2005 tmp = SSP_RX_MSB;
2006 etx = SSP_TX_MSB;
2007 }
2008 SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_RENDN_ST, 4);
2009 SSP_WRITE_BITS(chip->cr1, etx, SSP_CR1_MASK_TENDN_ST, 5);
2010 SSP_WRITE_BITS(chip->cr1, chip_info->rx_lev_trig,
2011 SSP_CR1_MASK_RXIFLSEL_ST, 7);
2012 SSP_WRITE_BITS(chip->cr1, chip_info->tx_lev_trig,
2013 SSP_CR1_MASK_TXIFLSEL_ST, 10);
2014 } else {
2015 SSP_WRITE_BITS(chip->cr0, bits - 1,
2016 SSP_CR0_MASK_DSS, 0);
2017 SSP_WRITE_BITS(chip->cr0, chip_info->iface,
2018 SSP_CR0_MASK_FRF, 4);
2019 }
2020
2021 /* Stuff that is common for all versions */
2022 if (spi->mode & SPI_CPOL)
2023 tmp = SSP_CLK_POL_IDLE_HIGH;
2024 else
2025 tmp = SSP_CLK_POL_IDLE_LOW;
2026 SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPO, 6);
2027
2028 if (spi->mode & SPI_CPHA)
2029 tmp = SSP_CLK_SECOND_EDGE;
2030 else
2031 tmp = SSP_CLK_FIRST_EDGE;
2032 SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPH, 7);
2033
2034 SSP_WRITE_BITS(chip->cr0, clk_freq.scr, SSP_CR0_MASK_SCR, 8);
2035 /* Loopback is available on all versions except PL023 */
2036 if (pl022->vendor->loopback) {
2037 if (spi->mode & SPI_LOOP)
2038 tmp = LOOPBACK_ENABLED;
2039 else
2040 tmp = LOOPBACK_DISABLED;
2041 SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_LBM, 0);
2042 }
2043 SSP_WRITE_BITS(chip->cr1, SSP_DISABLED, SSP_CR1_MASK_SSE, 1);
2044 SSP_WRITE_BITS(chip->cr1, chip_info->hierarchy, SSP_CR1_MASK_MS, 2);
2045 SSP_WRITE_BITS(chip->cr1, chip_info->slave_tx_disable, SSP_CR1_MASK_SOD,
2046 3);
2047
2048 /* Save controller_state */
2049 spi_set_ctldata(spi, chip);
2050 return status;
2051 err_config_params:
2052 spi_set_ctldata(spi, NULL);
2053 kfree(chip);
2054 return status;
2055}
2056
2057/**
2058 * pl022_cleanup - cleanup function registered to SPI master framework
2059 * @spi: spi device which is requesting cleanup
2060 *
2061 * This function is registered to the SPI framework for this SPI master
2062 * controller. It will free the runtime state of chip.
2063 */
2064static void pl022_cleanup(struct spi_device *spi)
2065{
2066 struct chip_data *chip = spi_get_ctldata(spi);
2067
2068 spi_set_ctldata(spi, NULL);
2069 kfree(chip);
2070}
2071
2072static struct pl022_ssp_controller *
2073pl022_platform_data_dt_get(struct device *dev)
2074{
2075 struct device_node *np = dev->of_node;
2076 struct pl022_ssp_controller *pd;
2077 u32 tmp;
2078
2079 if (!np) {
2080 dev_err(dev, "no dt node defined\n");
2081 return NULL;
2082 }
2083
2084 pd = devm_kzalloc(dev, sizeof(struct pl022_ssp_controller), GFP_KERNEL);
2085 if (!pd)
2086 return NULL;
2087
2088 pd->bus_id = -1;
2089 pd->enable_dma = 1;
2090 of_property_read_u32(np, "num-cs", &tmp);
2091 pd->num_chipselect = tmp;
2092 of_property_read_u32(np, "pl022,autosuspend-delay",
2093 &pd->autosuspend_delay);
2094 pd->rt = of_property_read_bool(np, "pl022,rt");
2095
2096 return pd;
2097}
2098
2099static int pl022_probe(struct amba_device *adev, const struct amba_id *id)
2100{
2101 struct device *dev = &adev->dev;
2102 struct pl022_ssp_controller *platform_info =
2103 dev_get_platdata(&adev->dev);
2104 struct spi_master *master;
2105 struct pl022 *pl022 = NULL; /*Data for this driver */
2106 struct device_node *np = adev->dev.of_node;
2107 int status = 0, i, num_cs;
2108
2109 dev_info(&adev->dev,
2110 "ARM PL022 driver, device ID: 0x%08x\n", adev->periphid);
2111 if (!platform_info && IS_ENABLED(CONFIG_OF))
2112 platform_info = pl022_platform_data_dt_get(dev);
2113
2114 if (!platform_info) {
2115 dev_err(dev, "probe: no platform data defined\n");
2116 return -ENODEV;
2117 }
2118
2119 if (platform_info->num_chipselect) {
2120 num_cs = platform_info->num_chipselect;
2121 } else {
2122 dev_err(dev, "probe: no chip select defined\n");
2123 return -ENODEV;
2124 }
2125
2126 /* Allocate master with space for data */
2127 master = spi_alloc_master(dev, sizeof(struct pl022));
2128 if (master == NULL) {
2129 dev_err(&adev->dev, "probe - cannot alloc SPI master\n");
2130 return -ENOMEM;
2131 }
2132
2133 pl022 = spi_master_get_devdata(master);
2134 pl022->master = master;
2135 pl022->master_info = platform_info;
2136 pl022->adev = adev;
2137 pl022->vendor = id->data;
2138 pl022->chipselects = devm_kzalloc(dev, num_cs * sizeof(int),
2139 GFP_KERNEL);
2140 if (!pl022->chipselects) {
2141 status = -ENOMEM;
2142 goto err_no_mem;
2143 }
2144
2145 /*
2146 * Bus Number Which has been Assigned to this SSP controller
2147 * on this board
2148 */
2149 master->bus_num = platform_info->bus_id;
2150 master->num_chipselect = num_cs;
2151 master->cleanup = pl022_cleanup;
2152 master->setup = pl022_setup;
2153 master->auto_runtime_pm = true;
2154 master->transfer_one_message = pl022_transfer_one_message;
2155 master->unprepare_transfer_hardware = pl022_unprepare_transfer_hardware;
2156 master->rt = platform_info->rt;
2157 master->dev.of_node = dev->of_node;
2158
2159 if (platform_info->num_chipselect && platform_info->chipselects) {
2160 for (i = 0; i < num_cs; i++)
2161 pl022->chipselects[i] = platform_info->chipselects[i];
2162 } else if (pl022->vendor->internal_cs_ctrl) {
2163 for (i = 0; i < num_cs; i++)
2164 pl022->chipselects[i] = i;
2165 } else if (IS_ENABLED(CONFIG_OF)) {
2166 for (i = 0; i < num_cs; i++) {
2167 int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
2168
2169 if (cs_gpio == -EPROBE_DEFER) {
2170 status = -EPROBE_DEFER;
2171 goto err_no_gpio;
2172 }
2173
2174 pl022->chipselects[i] = cs_gpio;
2175
2176 if (gpio_is_valid(cs_gpio)) {
2177 if (devm_gpio_request(dev, cs_gpio, "ssp-pl022"))
2178 dev_err(&adev->dev,
2179 "could not request %d gpio\n",
2180 cs_gpio);
2181 else if (gpio_direction_output(cs_gpio, 1))
2182 dev_err(&adev->dev,
2183 "could not set gpio %d as output\n",
2184 cs_gpio);
2185 }
2186 }
2187 }
2188
2189 /*
2190 * Supports mode 0-3, loopback, and active low CS. Transfers are
2191 * always MS bit first on the original pl022.
2192 */
2193 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
2194 if (pl022->vendor->extended_cr)
2195 master->mode_bits |= SPI_LSB_FIRST;
2196
2197 dev_dbg(&adev->dev, "BUSNO: %d\n", master->bus_num);
2198
2199 status = amba_request_regions(adev, NULL);
2200 if (status)
2201 goto err_no_ioregion;
2202
2203 pl022->phybase = adev->res.start;
2204 pl022->virtbase = devm_ioremap(dev, adev->res.start,
2205 resource_size(&adev->res));
2206 if (pl022->virtbase == NULL) {
2207 status = -ENOMEM;
2208 goto err_no_ioremap;
2209 }
2210 dev_info(&adev->dev, "mapped registers from %pa to %p\n",
2211 &adev->res.start, pl022->virtbase);
2212
2213 pl022->clk = devm_clk_get(&adev->dev, NULL);
2214 if (IS_ERR(pl022->clk)) {
2215 status = PTR_ERR(pl022->clk);
2216 dev_err(&adev->dev, "could not retrieve SSP/SPI bus clock\n");
2217 goto err_no_clk;
2218 }
2219
2220 status = clk_prepare_enable(pl022->clk);
2221 if (status) {
2222 dev_err(&adev->dev, "could not enable SSP/SPI bus clock\n");
2223 goto err_no_clk_en;
2224 }
2225
2226 /* Initialize transfer pump */
2227 tasklet_init(&pl022->pump_transfers, pump_transfers,
2228 (unsigned long)pl022);
2229
2230 /* Disable SSP */
2231 writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)),
2232 SSP_CR1(pl022->virtbase));
2233 load_ssp_default_config(pl022);
2234
2235 status = devm_request_irq(dev, adev->irq[0], pl022_interrupt_handler,
2236 0, "pl022", pl022);
2237 if (status < 0) {
2238 dev_err(&adev->dev, "probe - cannot get IRQ (%d)\n", status);
2239 goto err_no_irq;
2240 }
2241
2242 /* Get DMA channels, try autoconfiguration first */
2243 status = pl022_dma_autoprobe(pl022);
2244 if (status == -EPROBE_DEFER) {
2245 dev_dbg(dev, "deferring probe to get DMA channel\n");
2246 goto err_no_irq;
2247 }
2248
2249 /* If that failed, use channels from platform_info */
2250 if (status == 0)
2251 platform_info->enable_dma = 1;
2252 else if (platform_info->enable_dma) {
2253 status = pl022_dma_probe(pl022);
2254 if (status != 0)
2255 platform_info->enable_dma = 0;
2256 }
2257
2258 /* Register with the SPI framework */
2259 amba_set_drvdata(adev, pl022);
2260 status = devm_spi_register_master(&adev->dev, master);
2261 if (status != 0) {
2262 dev_err(&adev->dev,
2263 "probe - problem registering spi master\n");
2264 goto err_spi_register;
2265 }
2266 dev_dbg(dev, "probe succeeded\n");
2267
2268 /* let runtime pm put suspend */
2269 if (platform_info->autosuspend_delay > 0) {
2270 dev_info(&adev->dev,
2271 "will use autosuspend for runtime pm, delay %dms\n",
2272 platform_info->autosuspend_delay);
2273 pm_runtime_set_autosuspend_delay(dev,
2274 platform_info->autosuspend_delay);
2275 pm_runtime_use_autosuspend(dev);
2276 }
2277 pm_runtime_put(dev);
2278
2279 return 0;
2280
2281 err_spi_register:
2282 if (platform_info->enable_dma)
2283 pl022_dma_remove(pl022);
2284 err_no_irq:
2285 clk_disable_unprepare(pl022->clk);
2286 err_no_clk_en:
2287 err_no_clk:
2288 err_no_ioremap:
2289 amba_release_regions(adev);
2290 err_no_ioregion:
2291 err_no_gpio:
2292 err_no_mem:
2293 spi_master_put(master);
2294 return status;
2295}
2296
2297static int
2298pl022_remove(struct amba_device *adev)
2299{
2300 struct pl022 *pl022 = amba_get_drvdata(adev);
2301
2302 if (!pl022)
2303 return 0;
2304
2305 /*
2306 * undo pm_runtime_put() in probe. I assume that we're not
2307 * accessing the primecell here.
2308 */
2309 pm_runtime_get_noresume(&adev->dev);
2310
2311 load_ssp_default_config(pl022);
2312 if (pl022->master_info->enable_dma)
2313 pl022_dma_remove(pl022);
2314
2315 clk_disable_unprepare(pl022->clk);
2316 amba_release_regions(adev);
2317 tasklet_disable(&pl022->pump_transfers);
2318 return 0;
2319}
2320
2321#ifdef CONFIG_PM_SLEEP
2322static int pl022_suspend(struct device *dev)
2323{
2324 struct pl022 *pl022 = dev_get_drvdata(dev);
2325 int ret;
2326
2327 ret = spi_master_suspend(pl022->master);
2328 if (ret) {
2329 dev_warn(dev, "cannot suspend master\n");
2330 return ret;
2331 }
2332
2333 ret = pm_runtime_force_suspend(dev);
2334 if (ret) {
2335 spi_master_resume(pl022->master);
2336 return ret;
2337 }
2338
2339 pinctrl_pm_select_sleep_state(dev);
2340
2341 dev_dbg(dev, "suspended\n");
2342 return 0;
2343}
2344
2345static int pl022_resume(struct device *dev)
2346{
2347 struct pl022 *pl022 = dev_get_drvdata(dev);
2348 int ret;
2349
2350 ret = pm_runtime_force_resume(dev);
2351 if (ret)
2352 dev_err(dev, "problem resuming\n");
2353
2354 /* Start the queue running */
2355 ret = spi_master_resume(pl022->master);
2356 if (ret)
2357 dev_err(dev, "problem starting queue (%d)\n", ret);
2358 else
2359 dev_dbg(dev, "resumed\n");
2360
2361 return ret;
2362}
2363#endif
2364
2365#ifdef CONFIG_PM
2366static int pl022_runtime_suspend(struct device *dev)
2367{
2368 struct pl022 *pl022 = dev_get_drvdata(dev);
2369
2370 clk_disable_unprepare(pl022->clk);
2371 pinctrl_pm_select_idle_state(dev);
2372
2373 return 0;
2374}
2375
2376static int pl022_runtime_resume(struct device *dev)
2377{
2378 struct pl022 *pl022 = dev_get_drvdata(dev);
2379
2380 pinctrl_pm_select_default_state(dev);
2381 clk_prepare_enable(pl022->clk);
2382
2383 return 0;
2384}
2385#endif
2386
2387static const struct dev_pm_ops pl022_dev_pm_ops = {
2388 SET_SYSTEM_SLEEP_PM_OPS(pl022_suspend, pl022_resume)
2389 SET_RUNTIME_PM_OPS(pl022_runtime_suspend, pl022_runtime_resume, NULL)
2390};
2391
2392static struct vendor_data vendor_arm = {
2393 .fifodepth = 8,
2394 .max_bpw = 16,
2395 .unidir = false,
2396 .extended_cr = false,
2397 .pl023 = false,
2398 .loopback = true,
2399 .internal_cs_ctrl = false,
2400};
2401
2402static struct vendor_data vendor_st = {
2403 .fifodepth = 32,
2404 .max_bpw = 32,
2405 .unidir = false,
2406 .extended_cr = true,
2407 .pl023 = false,
2408 .loopback = true,
2409 .internal_cs_ctrl = false,
2410};
2411
2412static struct vendor_data vendor_st_pl023 = {
2413 .fifodepth = 32,
2414 .max_bpw = 32,
2415 .unidir = false,
2416 .extended_cr = true,
2417 .pl023 = true,
2418 .loopback = false,
2419 .internal_cs_ctrl = false,
2420};
2421
2422static struct vendor_data vendor_lsi = {
2423 .fifodepth = 8,
2424 .max_bpw = 16,
2425 .unidir = false,
2426 .extended_cr = false,
2427 .pl023 = false,
2428 .loopback = true,
2429 .internal_cs_ctrl = true,
2430};
2431
2432static struct amba_id pl022_ids[] = {
2433 {
2434 /*
2435 * ARM PL022 variant, this has a 16bit wide
2436 * and 8 locations deep TX/RX FIFO
2437 */
2438 .id = 0x00041022,
2439 .mask = 0x000fffff,
2440 .data = &vendor_arm,
2441 },
2442 {
2443 /*
2444 * ST Micro derivative, this has 32bit wide
2445 * and 32 locations deep TX/RX FIFO
2446 */
2447 .id = 0x01080022,
2448 .mask = 0xffffffff,
2449 .data = &vendor_st,
2450 },
2451 {
2452 /*
2453 * ST-Ericsson derivative "PL023" (this is not
2454 * an official ARM number), this is a PL022 SSP block
2455 * stripped to SPI mode only, it has 32bit wide
2456 * and 32 locations deep TX/RX FIFO but no extended
2457 * CR0/CR1 register
2458 */
2459 .id = 0x00080023,
2460 .mask = 0xffffffff,
2461 .data = &vendor_st_pl023,
2462 },
2463 {
2464 /*
2465 * PL022 variant that has a chip select control register whih
2466 * allows control of 5 output signals nCS[0:4].
2467 */
2468 .id = 0x000b6022,
2469 .mask = 0x000fffff,
2470 .data = &vendor_lsi,
2471 },
2472 { 0, 0 },
2473};
2474
2475MODULE_DEVICE_TABLE(amba, pl022_ids);
2476
2477static struct amba_driver pl022_driver = {
2478 .drv = {
2479 .name = "ssp-pl022",
2480 .pm = &pl022_dev_pm_ops,
2481 },
2482 .id_table = pl022_ids,
2483 .probe = pl022_probe,
2484 .remove = pl022_remove,
2485};
2486
2487static int __init pl022_init(void)
2488{
2489 return amba_driver_register(&pl022_driver);
2490}
2491subsys_initcall(pl022_init);
2492
2493static void __exit pl022_exit(void)
2494{
2495 amba_driver_unregister(&pl022_driver);
2496}
2497module_exit(pl022_exit);
2498
2499MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
2500MODULE_DESCRIPTION("PL022 SSP Controller Driver");
2501MODULE_LICENSE("GPL");
1/*
2 * A driver for the ARM PL022 PrimeCell SSP/SPI bus master.
3 *
4 * Copyright (C) 2008-2009 ST-Ericsson AB
5 * Copyright (C) 2006 STMicroelectronics Pvt. Ltd.
6 *
7 * Author: Linus Walleij <linus.walleij@stericsson.com>
8 *
9 * Initial version inspired by:
10 * linux-2.6.17-rc3-mm1/drivers/spi/pxa2xx_spi.c
11 * Initial adoption to PL022 by:
12 * Sachin Verma <sachin.verma@st.com>
13 *
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
18 *
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
23 */
24
25#include <linux/init.h>
26#include <linux/module.h>
27#include <linux/device.h>
28#include <linux/ioport.h>
29#include <linux/errno.h>
30#include <linux/interrupt.h>
31#include <linux/spi/spi.h>
32#include <linux/delay.h>
33#include <linux/clk.h>
34#include <linux/err.h>
35#include <linux/amba/bus.h>
36#include <linux/amba/pl022.h>
37#include <linux/io.h>
38#include <linux/slab.h>
39#include <linux/dmaengine.h>
40#include <linux/dma-mapping.h>
41#include <linux/scatterlist.h>
42#include <linux/pm_runtime.h>
43
44/*
45 * This macro is used to define some register default values.
46 * reg is masked with mask, the OR:ed with an (again masked)
47 * val shifted sb steps to the left.
48 */
49#define SSP_WRITE_BITS(reg, val, mask, sb) \
50 ((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask))))
51
52/*
53 * This macro is also used to define some default values.
54 * It will just shift val by sb steps to the left and mask
55 * the result with mask.
56 */
57#define GEN_MASK_BITS(val, mask, sb) \
58 (((val)<<(sb)) & (mask))
59
60#define DRIVE_TX 0
61#define DO_NOT_DRIVE_TX 1
62
63#define DO_NOT_QUEUE_DMA 0
64#define QUEUE_DMA 1
65
66#define RX_TRANSFER 1
67#define TX_TRANSFER 2
68
69/*
70 * Macros to access SSP Registers with their offsets
71 */
72#define SSP_CR0(r) (r + 0x000)
73#define SSP_CR1(r) (r + 0x004)
74#define SSP_DR(r) (r + 0x008)
75#define SSP_SR(r) (r + 0x00C)
76#define SSP_CPSR(r) (r + 0x010)
77#define SSP_IMSC(r) (r + 0x014)
78#define SSP_RIS(r) (r + 0x018)
79#define SSP_MIS(r) (r + 0x01C)
80#define SSP_ICR(r) (r + 0x020)
81#define SSP_DMACR(r) (r + 0x024)
82#define SSP_ITCR(r) (r + 0x080)
83#define SSP_ITIP(r) (r + 0x084)
84#define SSP_ITOP(r) (r + 0x088)
85#define SSP_TDR(r) (r + 0x08C)
86
87#define SSP_PID0(r) (r + 0xFE0)
88#define SSP_PID1(r) (r + 0xFE4)
89#define SSP_PID2(r) (r + 0xFE8)
90#define SSP_PID3(r) (r + 0xFEC)
91
92#define SSP_CID0(r) (r + 0xFF0)
93#define SSP_CID1(r) (r + 0xFF4)
94#define SSP_CID2(r) (r + 0xFF8)
95#define SSP_CID3(r) (r + 0xFFC)
96
97/*
98 * SSP Control Register 0 - SSP_CR0
99 */
100#define SSP_CR0_MASK_DSS (0x0FUL << 0)
101#define SSP_CR0_MASK_FRF (0x3UL << 4)
102#define SSP_CR0_MASK_SPO (0x1UL << 6)
103#define SSP_CR0_MASK_SPH (0x1UL << 7)
104#define SSP_CR0_MASK_SCR (0xFFUL << 8)
105
106/*
107 * The ST version of this block moves som bits
108 * in SSP_CR0 and extends it to 32 bits
109 */
110#define SSP_CR0_MASK_DSS_ST (0x1FUL << 0)
111#define SSP_CR0_MASK_HALFDUP_ST (0x1UL << 5)
112#define SSP_CR0_MASK_CSS_ST (0x1FUL << 16)
113#define SSP_CR0_MASK_FRF_ST (0x3UL << 21)
114
115/*
116 * SSP Control Register 0 - SSP_CR1
117 */
118#define SSP_CR1_MASK_LBM (0x1UL << 0)
119#define SSP_CR1_MASK_SSE (0x1UL << 1)
120#define SSP_CR1_MASK_MS (0x1UL << 2)
121#define SSP_CR1_MASK_SOD (0x1UL << 3)
122
123/*
124 * The ST version of this block adds some bits
125 * in SSP_CR1
126 */
127#define SSP_CR1_MASK_RENDN_ST (0x1UL << 4)
128#define SSP_CR1_MASK_TENDN_ST (0x1UL << 5)
129#define SSP_CR1_MASK_MWAIT_ST (0x1UL << 6)
130#define SSP_CR1_MASK_RXIFLSEL_ST (0x7UL << 7)
131#define SSP_CR1_MASK_TXIFLSEL_ST (0x7UL << 10)
132/* This one is only in the PL023 variant */
133#define SSP_CR1_MASK_FBCLKDEL_ST (0x7UL << 13)
134
135/*
136 * SSP Status Register - SSP_SR
137 */
138#define SSP_SR_MASK_TFE (0x1UL << 0) /* Transmit FIFO empty */
139#define SSP_SR_MASK_TNF (0x1UL << 1) /* Transmit FIFO not full */
140#define SSP_SR_MASK_RNE (0x1UL << 2) /* Receive FIFO not empty */
141#define SSP_SR_MASK_RFF (0x1UL << 3) /* Receive FIFO full */
142#define SSP_SR_MASK_BSY (0x1UL << 4) /* Busy Flag */
143
144/*
145 * SSP Clock Prescale Register - SSP_CPSR
146 */
147#define SSP_CPSR_MASK_CPSDVSR (0xFFUL << 0)
148
149/*
150 * SSP Interrupt Mask Set/Clear Register - SSP_IMSC
151 */
152#define SSP_IMSC_MASK_RORIM (0x1UL << 0) /* Receive Overrun Interrupt mask */
153#define SSP_IMSC_MASK_RTIM (0x1UL << 1) /* Receive timeout Interrupt mask */
154#define SSP_IMSC_MASK_RXIM (0x1UL << 2) /* Receive FIFO Interrupt mask */
155#define SSP_IMSC_MASK_TXIM (0x1UL << 3) /* Transmit FIFO Interrupt mask */
156
157/*
158 * SSP Raw Interrupt Status Register - SSP_RIS
159 */
160/* Receive Overrun Raw Interrupt status */
161#define SSP_RIS_MASK_RORRIS (0x1UL << 0)
162/* Receive Timeout Raw Interrupt status */
163#define SSP_RIS_MASK_RTRIS (0x1UL << 1)
164/* Receive FIFO Raw Interrupt status */
165#define SSP_RIS_MASK_RXRIS (0x1UL << 2)
166/* Transmit FIFO Raw Interrupt status */
167#define SSP_RIS_MASK_TXRIS (0x1UL << 3)
168
169/*
170 * SSP Masked Interrupt Status Register - SSP_MIS
171 */
172/* Receive Overrun Masked Interrupt status */
173#define SSP_MIS_MASK_RORMIS (0x1UL << 0)
174/* Receive Timeout Masked Interrupt status */
175#define SSP_MIS_MASK_RTMIS (0x1UL << 1)
176/* Receive FIFO Masked Interrupt status */
177#define SSP_MIS_MASK_RXMIS (0x1UL << 2)
178/* Transmit FIFO Masked Interrupt status */
179#define SSP_MIS_MASK_TXMIS (0x1UL << 3)
180
181/*
182 * SSP Interrupt Clear Register - SSP_ICR
183 */
184/* Receive Overrun Raw Clear Interrupt bit */
185#define SSP_ICR_MASK_RORIC (0x1UL << 0)
186/* Receive Timeout Clear Interrupt bit */
187#define SSP_ICR_MASK_RTIC (0x1UL << 1)
188
189/*
190 * SSP DMA Control Register - SSP_DMACR
191 */
192/* Receive DMA Enable bit */
193#define SSP_DMACR_MASK_RXDMAE (0x1UL << 0)
194/* Transmit DMA Enable bit */
195#define SSP_DMACR_MASK_TXDMAE (0x1UL << 1)
196
197/*
198 * SSP Integration Test control Register - SSP_ITCR
199 */
200#define SSP_ITCR_MASK_ITEN (0x1UL << 0)
201#define SSP_ITCR_MASK_TESTFIFO (0x1UL << 1)
202
203/*
204 * SSP Integration Test Input Register - SSP_ITIP
205 */
206#define ITIP_MASK_SSPRXD (0x1UL << 0)
207#define ITIP_MASK_SSPFSSIN (0x1UL << 1)
208#define ITIP_MASK_SSPCLKIN (0x1UL << 2)
209#define ITIP_MASK_RXDMAC (0x1UL << 3)
210#define ITIP_MASK_TXDMAC (0x1UL << 4)
211#define ITIP_MASK_SSPTXDIN (0x1UL << 5)
212
213/*
214 * SSP Integration Test output Register - SSP_ITOP
215 */
216#define ITOP_MASK_SSPTXD (0x1UL << 0)
217#define ITOP_MASK_SSPFSSOUT (0x1UL << 1)
218#define ITOP_MASK_SSPCLKOUT (0x1UL << 2)
219#define ITOP_MASK_SSPOEn (0x1UL << 3)
220#define ITOP_MASK_SSPCTLOEn (0x1UL << 4)
221#define ITOP_MASK_RORINTR (0x1UL << 5)
222#define ITOP_MASK_RTINTR (0x1UL << 6)
223#define ITOP_MASK_RXINTR (0x1UL << 7)
224#define ITOP_MASK_TXINTR (0x1UL << 8)
225#define ITOP_MASK_INTR (0x1UL << 9)
226#define ITOP_MASK_RXDMABREQ (0x1UL << 10)
227#define ITOP_MASK_RXDMASREQ (0x1UL << 11)
228#define ITOP_MASK_TXDMABREQ (0x1UL << 12)
229#define ITOP_MASK_TXDMASREQ (0x1UL << 13)
230
231/*
232 * SSP Test Data Register - SSP_TDR
233 */
234#define TDR_MASK_TESTDATA (0xFFFFFFFF)
235
236/*
237 * Message State
238 * we use the spi_message.state (void *) pointer to
239 * hold a single state value, that's why all this
240 * (void *) casting is done here.
241 */
242#define STATE_START ((void *) 0)
243#define STATE_RUNNING ((void *) 1)
244#define STATE_DONE ((void *) 2)
245#define STATE_ERROR ((void *) -1)
246
247/*
248 * SSP State - Whether Enabled or Disabled
249 */
250#define SSP_DISABLED (0)
251#define SSP_ENABLED (1)
252
253/*
254 * SSP DMA State - Whether DMA Enabled or Disabled
255 */
256#define SSP_DMA_DISABLED (0)
257#define SSP_DMA_ENABLED (1)
258
259/*
260 * SSP Clock Defaults
261 */
262#define SSP_DEFAULT_CLKRATE 0x2
263#define SSP_DEFAULT_PRESCALE 0x40
264
265/*
266 * SSP Clock Parameter ranges
267 */
268#define CPSDVR_MIN 0x02
269#define CPSDVR_MAX 0xFE
270#define SCR_MIN 0x00
271#define SCR_MAX 0xFF
272
273/*
274 * SSP Interrupt related Macros
275 */
276#define DEFAULT_SSP_REG_IMSC 0x0UL
277#define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC
278#define ENABLE_ALL_INTERRUPTS (~DEFAULT_SSP_REG_IMSC)
279
280#define CLEAR_ALL_INTERRUPTS 0x3
281
282#define SPI_POLLING_TIMEOUT 1000
283
284/*
285 * The type of reading going on on this chip
286 */
287enum ssp_reading {
288 READING_NULL,
289 READING_U8,
290 READING_U16,
291 READING_U32
292};
293
294/**
295 * The type of writing going on on this chip
296 */
297enum ssp_writing {
298 WRITING_NULL,
299 WRITING_U8,
300 WRITING_U16,
301 WRITING_U32
302};
303
304/**
305 * struct vendor_data - vendor-specific config parameters
306 * for PL022 derivates
307 * @fifodepth: depth of FIFOs (both)
308 * @max_bpw: maximum number of bits per word
309 * @unidir: supports unidirection transfers
310 * @extended_cr: 32 bit wide control register 0 with extra
311 * features and extra features in CR1 as found in the ST variants
312 * @pl023: supports a subset of the ST extensions called "PL023"
313 */
314struct vendor_data {
315 int fifodepth;
316 int max_bpw;
317 bool unidir;
318 bool extended_cr;
319 bool pl023;
320 bool loopback;
321};
322
323/**
324 * struct pl022 - This is the private SSP driver data structure
325 * @adev: AMBA device model hookup
326 * @vendor: vendor data for the IP block
327 * @phybase: the physical memory where the SSP device resides
328 * @virtbase: the virtual memory where the SSP is mapped
329 * @clk: outgoing clock "SPICLK" for the SPI bus
330 * @master: SPI framework hookup
331 * @master_info: controller-specific data from machine setup
332 * @kworker: thread struct for message pump
333 * @kworker_task: pointer to task for message pump kworker thread
334 * @pump_messages: work struct for scheduling work to the message pump
335 * @queue_lock: spinlock to syncronise access to message queue
336 * @queue: message queue
337 * @busy: message pump is busy
338 * @running: message pump is running
339 * @pump_transfers: Tasklet used in Interrupt Transfer mode
340 * @cur_msg: Pointer to current spi_message being processed
341 * @cur_transfer: Pointer to current spi_transfer
342 * @cur_chip: pointer to current clients chip(assigned from controller_state)
343 * @next_msg_cs_active: the next message in the queue has been examined
344 * and it was found that it uses the same chip select as the previous
345 * message, so we left it active after the previous transfer, and it's
346 * active already.
347 * @tx: current position in TX buffer to be read
348 * @tx_end: end position in TX buffer to be read
349 * @rx: current position in RX buffer to be written
350 * @rx_end: end position in RX buffer to be written
351 * @read: the type of read currently going on
352 * @write: the type of write currently going on
353 * @exp_fifo_level: expected FIFO level
354 * @dma_rx_channel: optional channel for RX DMA
355 * @dma_tx_channel: optional channel for TX DMA
356 * @sgt_rx: scattertable for the RX transfer
357 * @sgt_tx: scattertable for the TX transfer
358 * @dummypage: a dummy page used for driving data on the bus with DMA
359 */
360struct pl022 {
361 struct amba_device *adev;
362 struct vendor_data *vendor;
363 resource_size_t phybase;
364 void __iomem *virtbase;
365 struct clk *clk;
366 struct spi_master *master;
367 struct pl022_ssp_controller *master_info;
368 /* Message per-transfer pump */
369 struct tasklet_struct pump_transfers;
370 struct spi_message *cur_msg;
371 struct spi_transfer *cur_transfer;
372 struct chip_data *cur_chip;
373 bool next_msg_cs_active;
374 void *tx;
375 void *tx_end;
376 void *rx;
377 void *rx_end;
378 enum ssp_reading read;
379 enum ssp_writing write;
380 u32 exp_fifo_level;
381 enum ssp_rx_level_trig rx_lev_trig;
382 enum ssp_tx_level_trig tx_lev_trig;
383 /* DMA settings */
384#ifdef CONFIG_DMA_ENGINE
385 struct dma_chan *dma_rx_channel;
386 struct dma_chan *dma_tx_channel;
387 struct sg_table sgt_rx;
388 struct sg_table sgt_tx;
389 char *dummypage;
390 bool dma_running;
391#endif
392};
393
394/**
395 * struct chip_data - To maintain runtime state of SSP for each client chip
396 * @cr0: Value of control register CR0 of SSP - on later ST variants this
397 * register is 32 bits wide rather than just 16
398 * @cr1: Value of control register CR1 of SSP
399 * @dmacr: Value of DMA control Register of SSP
400 * @cpsr: Value of Clock prescale register
401 * @n_bytes: how many bytes(power of 2) reqd for a given data width of client
402 * @enable_dma: Whether to enable DMA or not
403 * @read: function ptr to be used to read when doing xfer for this chip
404 * @write: function ptr to be used to write when doing xfer for this chip
405 * @cs_control: chip select callback provided by chip
406 * @xfer_type: polling/interrupt/DMA
407 *
408 * Runtime state of the SSP controller, maintained per chip,
409 * This would be set according to the current message that would be served
410 */
411struct chip_data {
412 u32 cr0;
413 u16 cr1;
414 u16 dmacr;
415 u16 cpsr;
416 u8 n_bytes;
417 bool enable_dma;
418 enum ssp_reading read;
419 enum ssp_writing write;
420 void (*cs_control) (u32 command);
421 int xfer_type;
422};
423
424/**
425 * null_cs_control - Dummy chip select function
426 * @command: select/delect the chip
427 *
428 * If no chip select function is provided by client this is used as dummy
429 * chip select
430 */
431static void null_cs_control(u32 command)
432{
433 pr_debug("pl022: dummy chip select control, CS=0x%x\n", command);
434}
435
436/**
437 * giveback - current spi_message is over, schedule next message and call
438 * callback of this message. Assumes that caller already
439 * set message->status; dma and pio irqs are blocked
440 * @pl022: SSP driver private data structure
441 */
442static void giveback(struct pl022 *pl022)
443{
444 struct spi_transfer *last_transfer;
445 pl022->next_msg_cs_active = false;
446
447 last_transfer = list_entry(pl022->cur_msg->transfers.prev,
448 struct spi_transfer,
449 transfer_list);
450
451 /* Delay if requested before any change in chip select */
452 if (last_transfer->delay_usecs)
453 /*
454 * FIXME: This runs in interrupt context.
455 * Is this really smart?
456 */
457 udelay(last_transfer->delay_usecs);
458
459 if (!last_transfer->cs_change) {
460 struct spi_message *next_msg;
461
462 /*
463 * cs_change was not set. We can keep the chip select
464 * enabled if there is message in the queue and it is
465 * for the same spi device.
466 *
467 * We cannot postpone this until pump_messages, because
468 * after calling msg->complete (below) the driver that
469 * sent the current message could be unloaded, which
470 * could invalidate the cs_control() callback...
471 */
472 /* get a pointer to the next message, if any */
473 next_msg = spi_get_next_queued_message(pl022->master);
474
475 /*
476 * see if the next and current messages point
477 * to the same spi device.
478 */
479 if (next_msg && next_msg->spi != pl022->cur_msg->spi)
480 next_msg = NULL;
481 if (!next_msg || pl022->cur_msg->state == STATE_ERROR)
482 pl022->cur_chip->cs_control(SSP_CHIP_DESELECT);
483 else
484 pl022->next_msg_cs_active = true;
485
486 }
487
488 pl022->cur_msg = NULL;
489 pl022->cur_transfer = NULL;
490 pl022->cur_chip = NULL;
491 spi_finalize_current_message(pl022->master);
492
493 /* disable the SPI/SSP operation */
494 writew((readw(SSP_CR1(pl022->virtbase)) &
495 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
496
497}
498
499/**
500 * flush - flush the FIFO to reach a clean state
501 * @pl022: SSP driver private data structure
502 */
503static int flush(struct pl022 *pl022)
504{
505 unsigned long limit = loops_per_jiffy << 1;
506
507 dev_dbg(&pl022->adev->dev, "flush\n");
508 do {
509 while (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
510 readw(SSP_DR(pl022->virtbase));
511 } while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_BSY) && limit--);
512
513 pl022->exp_fifo_level = 0;
514
515 return limit;
516}
517
518/**
519 * restore_state - Load configuration of current chip
520 * @pl022: SSP driver private data structure
521 */
522static void restore_state(struct pl022 *pl022)
523{
524 struct chip_data *chip = pl022->cur_chip;
525
526 if (pl022->vendor->extended_cr)
527 writel(chip->cr0, SSP_CR0(pl022->virtbase));
528 else
529 writew(chip->cr0, SSP_CR0(pl022->virtbase));
530 writew(chip->cr1, SSP_CR1(pl022->virtbase));
531 writew(chip->dmacr, SSP_DMACR(pl022->virtbase));
532 writew(chip->cpsr, SSP_CPSR(pl022->virtbase));
533 writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
534 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
535}
536
537/*
538 * Default SSP Register Values
539 */
540#define DEFAULT_SSP_REG_CR0 ( \
541 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0) | \
542 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 4) | \
543 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
544 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
545 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
546)
547
548/* ST versions have slightly different bit layout */
549#define DEFAULT_SSP_REG_CR0_ST ( \
550 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
551 GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, SSP_CR0_MASK_HALFDUP_ST, 5) | \
552 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
553 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
554 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \
555 GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS_ST, 16) | \
556 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF_ST, 21) \
557)
558
559/* The PL023 version is slightly different again */
560#define DEFAULT_SSP_REG_CR0_ST_PL023 ( \
561 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
562 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
563 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
564 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
565)
566
567#define DEFAULT_SSP_REG_CR1 ( \
568 GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \
569 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
570 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
571 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) \
572)
573
574/* ST versions extend this register to use all 16 bits */
575#define DEFAULT_SSP_REG_CR1_ST ( \
576 DEFAULT_SSP_REG_CR1 | \
577 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
578 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
579 GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT_ST, 6) |\
580 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
581 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) \
582)
583
584/*
585 * The PL023 variant has further differences: no loopback mode, no microwire
586 * support, and a new clock feedback delay setting.
587 */
588#define DEFAULT_SSP_REG_CR1_ST_PL023 ( \
589 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
590 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
591 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \
592 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
593 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
594 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
595 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) | \
596 GEN_MASK_BITS(SSP_FEEDBACK_CLK_DELAY_NONE, SSP_CR1_MASK_FBCLKDEL_ST, 13) \
597)
598
599#define DEFAULT_SSP_REG_CPSR ( \
600 GEN_MASK_BITS(SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \
601)
602
603#define DEFAULT_SSP_REG_DMACR (\
604 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \
605 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \
606)
607
608/**
609 * load_ssp_default_config - Load default configuration for SSP
610 * @pl022: SSP driver private data structure
611 */
612static void load_ssp_default_config(struct pl022 *pl022)
613{
614 if (pl022->vendor->pl023) {
615 writel(DEFAULT_SSP_REG_CR0_ST_PL023, SSP_CR0(pl022->virtbase));
616 writew(DEFAULT_SSP_REG_CR1_ST_PL023, SSP_CR1(pl022->virtbase));
617 } else if (pl022->vendor->extended_cr) {
618 writel(DEFAULT_SSP_REG_CR0_ST, SSP_CR0(pl022->virtbase));
619 writew(DEFAULT_SSP_REG_CR1_ST, SSP_CR1(pl022->virtbase));
620 } else {
621 writew(DEFAULT_SSP_REG_CR0, SSP_CR0(pl022->virtbase));
622 writew(DEFAULT_SSP_REG_CR1, SSP_CR1(pl022->virtbase));
623 }
624 writew(DEFAULT_SSP_REG_DMACR, SSP_DMACR(pl022->virtbase));
625 writew(DEFAULT_SSP_REG_CPSR, SSP_CPSR(pl022->virtbase));
626 writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
627 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
628}
629
630/**
631 * This will write to TX and read from RX according to the parameters
632 * set in pl022.
633 */
634static void readwriter(struct pl022 *pl022)
635{
636
637 /*
638 * The FIFO depth is different between primecell variants.
639 * I believe filling in too much in the FIFO might cause
640 * errons in 8bit wide transfers on ARM variants (just 8 words
641 * FIFO, means only 8x8 = 64 bits in FIFO) at least.
642 *
643 * To prevent this issue, the TX FIFO is only filled to the
644 * unused RX FIFO fill length, regardless of what the TX
645 * FIFO status flag indicates.
646 */
647 dev_dbg(&pl022->adev->dev,
648 "%s, rx: %p, rxend: %p, tx: %p, txend: %p\n",
649 __func__, pl022->rx, pl022->rx_end, pl022->tx, pl022->tx_end);
650
651 /* Read as much as you can */
652 while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
653 && (pl022->rx < pl022->rx_end)) {
654 switch (pl022->read) {
655 case READING_NULL:
656 readw(SSP_DR(pl022->virtbase));
657 break;
658 case READING_U8:
659 *(u8 *) (pl022->rx) =
660 readw(SSP_DR(pl022->virtbase)) & 0xFFU;
661 break;
662 case READING_U16:
663 *(u16 *) (pl022->rx) =
664 (u16) readw(SSP_DR(pl022->virtbase));
665 break;
666 case READING_U32:
667 *(u32 *) (pl022->rx) =
668 readl(SSP_DR(pl022->virtbase));
669 break;
670 }
671 pl022->rx += (pl022->cur_chip->n_bytes);
672 pl022->exp_fifo_level--;
673 }
674 /*
675 * Write as much as possible up to the RX FIFO size
676 */
677 while ((pl022->exp_fifo_level < pl022->vendor->fifodepth)
678 && (pl022->tx < pl022->tx_end)) {
679 switch (pl022->write) {
680 case WRITING_NULL:
681 writew(0x0, SSP_DR(pl022->virtbase));
682 break;
683 case WRITING_U8:
684 writew(*(u8 *) (pl022->tx), SSP_DR(pl022->virtbase));
685 break;
686 case WRITING_U16:
687 writew((*(u16 *) (pl022->tx)), SSP_DR(pl022->virtbase));
688 break;
689 case WRITING_U32:
690 writel(*(u32 *) (pl022->tx), SSP_DR(pl022->virtbase));
691 break;
692 }
693 pl022->tx += (pl022->cur_chip->n_bytes);
694 pl022->exp_fifo_level++;
695 /*
696 * This inner reader takes care of things appearing in the RX
697 * FIFO as we're transmitting. This will happen a lot since the
698 * clock starts running when you put things into the TX FIFO,
699 * and then things are continuously clocked into the RX FIFO.
700 */
701 while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
702 && (pl022->rx < pl022->rx_end)) {
703 switch (pl022->read) {
704 case READING_NULL:
705 readw(SSP_DR(pl022->virtbase));
706 break;
707 case READING_U8:
708 *(u8 *) (pl022->rx) =
709 readw(SSP_DR(pl022->virtbase)) & 0xFFU;
710 break;
711 case READING_U16:
712 *(u16 *) (pl022->rx) =
713 (u16) readw(SSP_DR(pl022->virtbase));
714 break;
715 case READING_U32:
716 *(u32 *) (pl022->rx) =
717 readl(SSP_DR(pl022->virtbase));
718 break;
719 }
720 pl022->rx += (pl022->cur_chip->n_bytes);
721 pl022->exp_fifo_level--;
722 }
723 }
724 /*
725 * When we exit here the TX FIFO should be full and the RX FIFO
726 * should be empty
727 */
728}
729
730/**
731 * next_transfer - Move to the Next transfer in the current spi message
732 * @pl022: SSP driver private data structure
733 *
734 * This function moves though the linked list of spi transfers in the
735 * current spi message and returns with the state of current spi
736 * message i.e whether its last transfer is done(STATE_DONE) or
737 * Next transfer is ready(STATE_RUNNING)
738 */
739static void *next_transfer(struct pl022 *pl022)
740{
741 struct spi_message *msg = pl022->cur_msg;
742 struct spi_transfer *trans = pl022->cur_transfer;
743
744 /* Move to next transfer */
745 if (trans->transfer_list.next != &msg->transfers) {
746 pl022->cur_transfer =
747 list_entry(trans->transfer_list.next,
748 struct spi_transfer, transfer_list);
749 return STATE_RUNNING;
750 }
751 return STATE_DONE;
752}
753
754/*
755 * This DMA functionality is only compiled in if we have
756 * access to the generic DMA devices/DMA engine.
757 */
758#ifdef CONFIG_DMA_ENGINE
759static void unmap_free_dma_scatter(struct pl022 *pl022)
760{
761 /* Unmap and free the SG tables */
762 dma_unmap_sg(pl022->dma_tx_channel->device->dev, pl022->sgt_tx.sgl,
763 pl022->sgt_tx.nents, DMA_TO_DEVICE);
764 dma_unmap_sg(pl022->dma_rx_channel->device->dev, pl022->sgt_rx.sgl,
765 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
766 sg_free_table(&pl022->sgt_rx);
767 sg_free_table(&pl022->sgt_tx);
768}
769
770static void dma_callback(void *data)
771{
772 struct pl022 *pl022 = data;
773 struct spi_message *msg = pl022->cur_msg;
774
775 BUG_ON(!pl022->sgt_rx.sgl);
776
777#ifdef VERBOSE_DEBUG
778 /*
779 * Optionally dump out buffers to inspect contents, this is
780 * good if you want to convince yourself that the loopback
781 * read/write contents are the same, when adopting to a new
782 * DMA engine.
783 */
784 {
785 struct scatterlist *sg;
786 unsigned int i;
787
788 dma_sync_sg_for_cpu(&pl022->adev->dev,
789 pl022->sgt_rx.sgl,
790 pl022->sgt_rx.nents,
791 DMA_FROM_DEVICE);
792
793 for_each_sg(pl022->sgt_rx.sgl, sg, pl022->sgt_rx.nents, i) {
794 dev_dbg(&pl022->adev->dev, "SPI RX SG ENTRY: %d", i);
795 print_hex_dump(KERN_ERR, "SPI RX: ",
796 DUMP_PREFIX_OFFSET,
797 16,
798 1,
799 sg_virt(sg),
800 sg_dma_len(sg),
801 1);
802 }
803 for_each_sg(pl022->sgt_tx.sgl, sg, pl022->sgt_tx.nents, i) {
804 dev_dbg(&pl022->adev->dev, "SPI TX SG ENTRY: %d", i);
805 print_hex_dump(KERN_ERR, "SPI TX: ",
806 DUMP_PREFIX_OFFSET,
807 16,
808 1,
809 sg_virt(sg),
810 sg_dma_len(sg),
811 1);
812 }
813 }
814#endif
815
816 unmap_free_dma_scatter(pl022);
817
818 /* Update total bytes transferred */
819 msg->actual_length += pl022->cur_transfer->len;
820 if (pl022->cur_transfer->cs_change)
821 pl022->cur_chip->
822 cs_control(SSP_CHIP_DESELECT);
823
824 /* Move to next transfer */
825 msg->state = next_transfer(pl022);
826 tasklet_schedule(&pl022->pump_transfers);
827}
828
829static void setup_dma_scatter(struct pl022 *pl022,
830 void *buffer,
831 unsigned int length,
832 struct sg_table *sgtab)
833{
834 struct scatterlist *sg;
835 int bytesleft = length;
836 void *bufp = buffer;
837 int mapbytes;
838 int i;
839
840 if (buffer) {
841 for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
842 /*
843 * If there are less bytes left than what fits
844 * in the current page (plus page alignment offset)
845 * we just feed in this, else we stuff in as much
846 * as we can.
847 */
848 if (bytesleft < (PAGE_SIZE - offset_in_page(bufp)))
849 mapbytes = bytesleft;
850 else
851 mapbytes = PAGE_SIZE - offset_in_page(bufp);
852 sg_set_page(sg, virt_to_page(bufp),
853 mapbytes, offset_in_page(bufp));
854 bufp += mapbytes;
855 bytesleft -= mapbytes;
856 dev_dbg(&pl022->adev->dev,
857 "set RX/TX target page @ %p, %d bytes, %d left\n",
858 bufp, mapbytes, bytesleft);
859 }
860 } else {
861 /* Map the dummy buffer on every page */
862 for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
863 if (bytesleft < PAGE_SIZE)
864 mapbytes = bytesleft;
865 else
866 mapbytes = PAGE_SIZE;
867 sg_set_page(sg, virt_to_page(pl022->dummypage),
868 mapbytes, 0);
869 bytesleft -= mapbytes;
870 dev_dbg(&pl022->adev->dev,
871 "set RX/TX to dummy page %d bytes, %d left\n",
872 mapbytes, bytesleft);
873
874 }
875 }
876 BUG_ON(bytesleft);
877}
878
879/**
880 * configure_dma - configures the channels for the next transfer
881 * @pl022: SSP driver's private data structure
882 */
883static int configure_dma(struct pl022 *pl022)
884{
885 struct dma_slave_config rx_conf = {
886 .src_addr = SSP_DR(pl022->phybase),
887 .direction = DMA_DEV_TO_MEM,
888 .device_fc = false,
889 };
890 struct dma_slave_config tx_conf = {
891 .dst_addr = SSP_DR(pl022->phybase),
892 .direction = DMA_MEM_TO_DEV,
893 .device_fc = false,
894 };
895 unsigned int pages;
896 int ret;
897 int rx_sglen, tx_sglen;
898 struct dma_chan *rxchan = pl022->dma_rx_channel;
899 struct dma_chan *txchan = pl022->dma_tx_channel;
900 struct dma_async_tx_descriptor *rxdesc;
901 struct dma_async_tx_descriptor *txdesc;
902
903 /* Check that the channels are available */
904 if (!rxchan || !txchan)
905 return -ENODEV;
906
907 /*
908 * If supplied, the DMA burstsize should equal the FIFO trigger level.
909 * Notice that the DMA engine uses one-to-one mapping. Since we can
910 * not trigger on 2 elements this needs explicit mapping rather than
911 * calculation.
912 */
913 switch (pl022->rx_lev_trig) {
914 case SSP_RX_1_OR_MORE_ELEM:
915 rx_conf.src_maxburst = 1;
916 break;
917 case SSP_RX_4_OR_MORE_ELEM:
918 rx_conf.src_maxburst = 4;
919 break;
920 case SSP_RX_8_OR_MORE_ELEM:
921 rx_conf.src_maxburst = 8;
922 break;
923 case SSP_RX_16_OR_MORE_ELEM:
924 rx_conf.src_maxburst = 16;
925 break;
926 case SSP_RX_32_OR_MORE_ELEM:
927 rx_conf.src_maxburst = 32;
928 break;
929 default:
930 rx_conf.src_maxburst = pl022->vendor->fifodepth >> 1;
931 break;
932 }
933
934 switch (pl022->tx_lev_trig) {
935 case SSP_TX_1_OR_MORE_EMPTY_LOC:
936 tx_conf.dst_maxburst = 1;
937 break;
938 case SSP_TX_4_OR_MORE_EMPTY_LOC:
939 tx_conf.dst_maxburst = 4;
940 break;
941 case SSP_TX_8_OR_MORE_EMPTY_LOC:
942 tx_conf.dst_maxburst = 8;
943 break;
944 case SSP_TX_16_OR_MORE_EMPTY_LOC:
945 tx_conf.dst_maxburst = 16;
946 break;
947 case SSP_TX_32_OR_MORE_EMPTY_LOC:
948 tx_conf.dst_maxburst = 32;
949 break;
950 default:
951 tx_conf.dst_maxburst = pl022->vendor->fifodepth >> 1;
952 break;
953 }
954
955 switch (pl022->read) {
956 case READING_NULL:
957 /* Use the same as for writing */
958 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
959 break;
960 case READING_U8:
961 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
962 break;
963 case READING_U16:
964 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
965 break;
966 case READING_U32:
967 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
968 break;
969 }
970
971 switch (pl022->write) {
972 case WRITING_NULL:
973 /* Use the same as for reading */
974 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
975 break;
976 case WRITING_U8:
977 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
978 break;
979 case WRITING_U16:
980 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
981 break;
982 case WRITING_U32:
983 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
984 break;
985 }
986
987 /* SPI pecularity: we need to read and write the same width */
988 if (rx_conf.src_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
989 rx_conf.src_addr_width = tx_conf.dst_addr_width;
990 if (tx_conf.dst_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
991 tx_conf.dst_addr_width = rx_conf.src_addr_width;
992 BUG_ON(rx_conf.src_addr_width != tx_conf.dst_addr_width);
993
994 dmaengine_slave_config(rxchan, &rx_conf);
995 dmaengine_slave_config(txchan, &tx_conf);
996
997 /* Create sglists for the transfers */
998 pages = DIV_ROUND_UP(pl022->cur_transfer->len, PAGE_SIZE);
999 dev_dbg(&pl022->adev->dev, "using %d pages for transfer\n", pages);
1000
1001 ret = sg_alloc_table(&pl022->sgt_rx, pages, GFP_ATOMIC);
1002 if (ret)
1003 goto err_alloc_rx_sg;
1004
1005 ret = sg_alloc_table(&pl022->sgt_tx, pages, GFP_ATOMIC);
1006 if (ret)
1007 goto err_alloc_tx_sg;
1008
1009 /* Fill in the scatterlists for the RX+TX buffers */
1010 setup_dma_scatter(pl022, pl022->rx,
1011 pl022->cur_transfer->len, &pl022->sgt_rx);
1012 setup_dma_scatter(pl022, pl022->tx,
1013 pl022->cur_transfer->len, &pl022->sgt_tx);
1014
1015 /* Map DMA buffers */
1016 rx_sglen = dma_map_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
1017 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
1018 if (!rx_sglen)
1019 goto err_rx_sgmap;
1020
1021 tx_sglen = dma_map_sg(txchan->device->dev, pl022->sgt_tx.sgl,
1022 pl022->sgt_tx.nents, DMA_TO_DEVICE);
1023 if (!tx_sglen)
1024 goto err_tx_sgmap;
1025
1026 /* Send both scatterlists */
1027 rxdesc = dmaengine_prep_slave_sg(rxchan,
1028 pl022->sgt_rx.sgl,
1029 rx_sglen,
1030 DMA_DEV_TO_MEM,
1031 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1032 if (!rxdesc)
1033 goto err_rxdesc;
1034
1035 txdesc = dmaengine_prep_slave_sg(txchan,
1036 pl022->sgt_tx.sgl,
1037 tx_sglen,
1038 DMA_MEM_TO_DEV,
1039 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1040 if (!txdesc)
1041 goto err_txdesc;
1042
1043 /* Put the callback on the RX transfer only, that should finish last */
1044 rxdesc->callback = dma_callback;
1045 rxdesc->callback_param = pl022;
1046
1047 /* Submit and fire RX and TX with TX last so we're ready to read! */
1048 dmaengine_submit(rxdesc);
1049 dmaengine_submit(txdesc);
1050 dma_async_issue_pending(rxchan);
1051 dma_async_issue_pending(txchan);
1052 pl022->dma_running = true;
1053
1054 return 0;
1055
1056err_txdesc:
1057 dmaengine_terminate_all(txchan);
1058err_rxdesc:
1059 dmaengine_terminate_all(rxchan);
1060 dma_unmap_sg(txchan->device->dev, pl022->sgt_tx.sgl,
1061 pl022->sgt_tx.nents, DMA_TO_DEVICE);
1062err_tx_sgmap:
1063 dma_unmap_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
1064 pl022->sgt_tx.nents, DMA_FROM_DEVICE);
1065err_rx_sgmap:
1066 sg_free_table(&pl022->sgt_tx);
1067err_alloc_tx_sg:
1068 sg_free_table(&pl022->sgt_rx);
1069err_alloc_rx_sg:
1070 return -ENOMEM;
1071}
1072
1073static int __devinit pl022_dma_probe(struct pl022 *pl022)
1074{
1075 dma_cap_mask_t mask;
1076
1077 /* Try to acquire a generic DMA engine slave channel */
1078 dma_cap_zero(mask);
1079 dma_cap_set(DMA_SLAVE, mask);
1080 /*
1081 * We need both RX and TX channels to do DMA, else do none
1082 * of them.
1083 */
1084 pl022->dma_rx_channel = dma_request_channel(mask,
1085 pl022->master_info->dma_filter,
1086 pl022->master_info->dma_rx_param);
1087 if (!pl022->dma_rx_channel) {
1088 dev_dbg(&pl022->adev->dev, "no RX DMA channel!\n");
1089 goto err_no_rxchan;
1090 }
1091
1092 pl022->dma_tx_channel = dma_request_channel(mask,
1093 pl022->master_info->dma_filter,
1094 pl022->master_info->dma_tx_param);
1095 if (!pl022->dma_tx_channel) {
1096 dev_dbg(&pl022->adev->dev, "no TX DMA channel!\n");
1097 goto err_no_txchan;
1098 }
1099
1100 pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
1101 if (!pl022->dummypage) {
1102 dev_dbg(&pl022->adev->dev, "no DMA dummypage!\n");
1103 goto err_no_dummypage;
1104 }
1105
1106 dev_info(&pl022->adev->dev, "setup for DMA on RX %s, TX %s\n",
1107 dma_chan_name(pl022->dma_rx_channel),
1108 dma_chan_name(pl022->dma_tx_channel));
1109
1110 return 0;
1111
1112err_no_dummypage:
1113 dma_release_channel(pl022->dma_tx_channel);
1114err_no_txchan:
1115 dma_release_channel(pl022->dma_rx_channel);
1116 pl022->dma_rx_channel = NULL;
1117err_no_rxchan:
1118 dev_err(&pl022->adev->dev,
1119 "Failed to work in dma mode, work without dma!\n");
1120 return -ENODEV;
1121}
1122
1123static void terminate_dma(struct pl022 *pl022)
1124{
1125 struct dma_chan *rxchan = pl022->dma_rx_channel;
1126 struct dma_chan *txchan = pl022->dma_tx_channel;
1127
1128 dmaengine_terminate_all(rxchan);
1129 dmaengine_terminate_all(txchan);
1130 unmap_free_dma_scatter(pl022);
1131 pl022->dma_running = false;
1132}
1133
1134static void pl022_dma_remove(struct pl022 *pl022)
1135{
1136 if (pl022->dma_running)
1137 terminate_dma(pl022);
1138 if (pl022->dma_tx_channel)
1139 dma_release_channel(pl022->dma_tx_channel);
1140 if (pl022->dma_rx_channel)
1141 dma_release_channel(pl022->dma_rx_channel);
1142 kfree(pl022->dummypage);
1143}
1144
1145#else
1146static inline int configure_dma(struct pl022 *pl022)
1147{
1148 return -ENODEV;
1149}
1150
1151static inline int pl022_dma_probe(struct pl022 *pl022)
1152{
1153 return 0;
1154}
1155
1156static inline void pl022_dma_remove(struct pl022 *pl022)
1157{
1158}
1159#endif
1160
1161/**
1162 * pl022_interrupt_handler - Interrupt handler for SSP controller
1163 *
1164 * This function handles interrupts generated for an interrupt based transfer.
1165 * If a receive overrun (ROR) interrupt is there then we disable SSP, flag the
1166 * current message's state as STATE_ERROR and schedule the tasklet
1167 * pump_transfers which will do the postprocessing of the current message by
1168 * calling giveback(). Otherwise it reads data from RX FIFO till there is no
1169 * more data, and writes data in TX FIFO till it is not full. If we complete
1170 * the transfer we move to the next transfer and schedule the tasklet.
1171 */
1172static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id)
1173{
1174 struct pl022 *pl022 = dev_id;
1175 struct spi_message *msg = pl022->cur_msg;
1176 u16 irq_status = 0;
1177 u16 flag = 0;
1178
1179 if (unlikely(!msg)) {
1180 dev_err(&pl022->adev->dev,
1181 "bad message state in interrupt handler");
1182 /* Never fail */
1183 return IRQ_HANDLED;
1184 }
1185
1186 /* Read the Interrupt Status Register */
1187 irq_status = readw(SSP_MIS(pl022->virtbase));
1188
1189 if (unlikely(!irq_status))
1190 return IRQ_NONE;
1191
1192 /*
1193 * This handles the FIFO interrupts, the timeout
1194 * interrupts are flatly ignored, they cannot be
1195 * trusted.
1196 */
1197 if (unlikely(irq_status & SSP_MIS_MASK_RORMIS)) {
1198 /*
1199 * Overrun interrupt - bail out since our Data has been
1200 * corrupted
1201 */
1202 dev_err(&pl022->adev->dev, "FIFO overrun\n");
1203 if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RFF)
1204 dev_err(&pl022->adev->dev,
1205 "RXFIFO is full\n");
1206 if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_TNF)
1207 dev_err(&pl022->adev->dev,
1208 "TXFIFO is full\n");
1209
1210 /*
1211 * Disable and clear interrupts, disable SSP,
1212 * mark message with bad status so it can be
1213 * retried.
1214 */
1215 writew(DISABLE_ALL_INTERRUPTS,
1216 SSP_IMSC(pl022->virtbase));
1217 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1218 writew((readw(SSP_CR1(pl022->virtbase)) &
1219 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1220 msg->state = STATE_ERROR;
1221
1222 /* Schedule message queue handler */
1223 tasklet_schedule(&pl022->pump_transfers);
1224 return IRQ_HANDLED;
1225 }
1226
1227 readwriter(pl022);
1228
1229 if ((pl022->tx == pl022->tx_end) && (flag == 0)) {
1230 flag = 1;
1231 /* Disable Transmit interrupt, enable receive interrupt */
1232 writew((readw(SSP_IMSC(pl022->virtbase)) &
1233 ~SSP_IMSC_MASK_TXIM) | SSP_IMSC_MASK_RXIM,
1234 SSP_IMSC(pl022->virtbase));
1235 }
1236
1237 /*
1238 * Since all transactions must write as much as shall be read,
1239 * we can conclude the entire transaction once RX is complete.
1240 * At this point, all TX will always be finished.
1241 */
1242 if (pl022->rx >= pl022->rx_end) {
1243 writew(DISABLE_ALL_INTERRUPTS,
1244 SSP_IMSC(pl022->virtbase));
1245 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1246 if (unlikely(pl022->rx > pl022->rx_end)) {
1247 dev_warn(&pl022->adev->dev, "read %u surplus "
1248 "bytes (did you request an odd "
1249 "number of bytes on a 16bit bus?)\n",
1250 (u32) (pl022->rx - pl022->rx_end));
1251 }
1252 /* Update total bytes transferred */
1253 msg->actual_length += pl022->cur_transfer->len;
1254 if (pl022->cur_transfer->cs_change)
1255 pl022->cur_chip->
1256 cs_control(SSP_CHIP_DESELECT);
1257 /* Move to next transfer */
1258 msg->state = next_transfer(pl022);
1259 tasklet_schedule(&pl022->pump_transfers);
1260 return IRQ_HANDLED;
1261 }
1262
1263 return IRQ_HANDLED;
1264}
1265
1266/**
1267 * This sets up the pointers to memory for the next message to
1268 * send out on the SPI bus.
1269 */
1270static int set_up_next_transfer(struct pl022 *pl022,
1271 struct spi_transfer *transfer)
1272{
1273 int residue;
1274
1275 /* Sanity check the message for this bus width */
1276 residue = pl022->cur_transfer->len % pl022->cur_chip->n_bytes;
1277 if (unlikely(residue != 0)) {
1278 dev_err(&pl022->adev->dev,
1279 "message of %u bytes to transmit but the current "
1280 "chip bus has a data width of %u bytes!\n",
1281 pl022->cur_transfer->len,
1282 pl022->cur_chip->n_bytes);
1283 dev_err(&pl022->adev->dev, "skipping this message\n");
1284 return -EIO;
1285 }
1286 pl022->tx = (void *)transfer->tx_buf;
1287 pl022->tx_end = pl022->tx + pl022->cur_transfer->len;
1288 pl022->rx = (void *)transfer->rx_buf;
1289 pl022->rx_end = pl022->rx + pl022->cur_transfer->len;
1290 pl022->write =
1291 pl022->tx ? pl022->cur_chip->write : WRITING_NULL;
1292 pl022->read = pl022->rx ? pl022->cur_chip->read : READING_NULL;
1293 return 0;
1294}
1295
1296/**
1297 * pump_transfers - Tasklet function which schedules next transfer
1298 * when running in interrupt or DMA transfer mode.
1299 * @data: SSP driver private data structure
1300 *
1301 */
1302static void pump_transfers(unsigned long data)
1303{
1304 struct pl022 *pl022 = (struct pl022 *) data;
1305 struct spi_message *message = NULL;
1306 struct spi_transfer *transfer = NULL;
1307 struct spi_transfer *previous = NULL;
1308
1309 /* Get current state information */
1310 message = pl022->cur_msg;
1311 transfer = pl022->cur_transfer;
1312
1313 /* Handle for abort */
1314 if (message->state == STATE_ERROR) {
1315 message->status = -EIO;
1316 giveback(pl022);
1317 return;
1318 }
1319
1320 /* Handle end of message */
1321 if (message->state == STATE_DONE) {
1322 message->status = 0;
1323 giveback(pl022);
1324 return;
1325 }
1326
1327 /* Delay if requested at end of transfer before CS change */
1328 if (message->state == STATE_RUNNING) {
1329 previous = list_entry(transfer->transfer_list.prev,
1330 struct spi_transfer,
1331 transfer_list);
1332 if (previous->delay_usecs)
1333 /*
1334 * FIXME: This runs in interrupt context.
1335 * Is this really smart?
1336 */
1337 udelay(previous->delay_usecs);
1338
1339 /* Reselect chip select only if cs_change was requested */
1340 if (previous->cs_change)
1341 pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
1342 } else {
1343 /* STATE_START */
1344 message->state = STATE_RUNNING;
1345 }
1346
1347 if (set_up_next_transfer(pl022, transfer)) {
1348 message->state = STATE_ERROR;
1349 message->status = -EIO;
1350 giveback(pl022);
1351 return;
1352 }
1353 /* Flush the FIFOs and let's go! */
1354 flush(pl022);
1355
1356 if (pl022->cur_chip->enable_dma) {
1357 if (configure_dma(pl022)) {
1358 dev_dbg(&pl022->adev->dev,
1359 "configuration of DMA failed, fall back to interrupt mode\n");
1360 goto err_config_dma;
1361 }
1362 return;
1363 }
1364
1365err_config_dma:
1366 /* enable all interrupts except RX */
1367 writew(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM, SSP_IMSC(pl022->virtbase));
1368}
1369
1370static void do_interrupt_dma_transfer(struct pl022 *pl022)
1371{
1372 /*
1373 * Default is to enable all interrupts except RX -
1374 * this will be enabled once TX is complete
1375 */
1376 u32 irqflags = ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM;
1377
1378 /* Enable target chip, if not already active */
1379 if (!pl022->next_msg_cs_active)
1380 pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
1381
1382 if (set_up_next_transfer(pl022, pl022->cur_transfer)) {
1383 /* Error path */
1384 pl022->cur_msg->state = STATE_ERROR;
1385 pl022->cur_msg->status = -EIO;
1386 giveback(pl022);
1387 return;
1388 }
1389 /* If we're using DMA, set up DMA here */
1390 if (pl022->cur_chip->enable_dma) {
1391 /* Configure DMA transfer */
1392 if (configure_dma(pl022)) {
1393 dev_dbg(&pl022->adev->dev,
1394 "configuration of DMA failed, fall back to interrupt mode\n");
1395 goto err_config_dma;
1396 }
1397 /* Disable interrupts in DMA mode, IRQ from DMA controller */
1398 irqflags = DISABLE_ALL_INTERRUPTS;
1399 }
1400err_config_dma:
1401 /* Enable SSP, turn on interrupts */
1402 writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1403 SSP_CR1(pl022->virtbase));
1404 writew(irqflags, SSP_IMSC(pl022->virtbase));
1405}
1406
1407static void do_polling_transfer(struct pl022 *pl022)
1408{
1409 struct spi_message *message = NULL;
1410 struct spi_transfer *transfer = NULL;
1411 struct spi_transfer *previous = NULL;
1412 struct chip_data *chip;
1413 unsigned long time, timeout;
1414
1415 chip = pl022->cur_chip;
1416 message = pl022->cur_msg;
1417
1418 while (message->state != STATE_DONE) {
1419 /* Handle for abort */
1420 if (message->state == STATE_ERROR)
1421 break;
1422 transfer = pl022->cur_transfer;
1423
1424 /* Delay if requested at end of transfer */
1425 if (message->state == STATE_RUNNING) {
1426 previous =
1427 list_entry(transfer->transfer_list.prev,
1428 struct spi_transfer, transfer_list);
1429 if (previous->delay_usecs)
1430 udelay(previous->delay_usecs);
1431 if (previous->cs_change)
1432 pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
1433 } else {
1434 /* STATE_START */
1435 message->state = STATE_RUNNING;
1436 if (!pl022->next_msg_cs_active)
1437 pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
1438 }
1439
1440 /* Configuration Changing Per Transfer */
1441 if (set_up_next_transfer(pl022, transfer)) {
1442 /* Error path */
1443 message->state = STATE_ERROR;
1444 break;
1445 }
1446 /* Flush FIFOs and enable SSP */
1447 flush(pl022);
1448 writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1449 SSP_CR1(pl022->virtbase));
1450
1451 dev_dbg(&pl022->adev->dev, "polling transfer ongoing ...\n");
1452
1453 timeout = jiffies + msecs_to_jiffies(SPI_POLLING_TIMEOUT);
1454 while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end) {
1455 time = jiffies;
1456 readwriter(pl022);
1457 if (time_after(time, timeout)) {
1458 dev_warn(&pl022->adev->dev,
1459 "%s: timeout!\n", __func__);
1460 message->state = STATE_ERROR;
1461 goto out;
1462 }
1463 cpu_relax();
1464 }
1465
1466 /* Update total byte transferred */
1467 message->actual_length += pl022->cur_transfer->len;
1468 if (pl022->cur_transfer->cs_change)
1469 pl022->cur_chip->cs_control(SSP_CHIP_DESELECT);
1470 /* Move to next transfer */
1471 message->state = next_transfer(pl022);
1472 }
1473out:
1474 /* Handle end of message */
1475 if (message->state == STATE_DONE)
1476 message->status = 0;
1477 else
1478 message->status = -EIO;
1479
1480 giveback(pl022);
1481 return;
1482}
1483
1484static int pl022_transfer_one_message(struct spi_master *master,
1485 struct spi_message *msg)
1486{
1487 struct pl022 *pl022 = spi_master_get_devdata(master);
1488
1489 /* Initial message state */
1490 pl022->cur_msg = msg;
1491 msg->state = STATE_START;
1492
1493 pl022->cur_transfer = list_entry(msg->transfers.next,
1494 struct spi_transfer, transfer_list);
1495
1496 /* Setup the SPI using the per chip configuration */
1497 pl022->cur_chip = spi_get_ctldata(msg->spi);
1498
1499 restore_state(pl022);
1500 flush(pl022);
1501
1502 if (pl022->cur_chip->xfer_type == POLLING_TRANSFER)
1503 do_polling_transfer(pl022);
1504 else
1505 do_interrupt_dma_transfer(pl022);
1506
1507 return 0;
1508}
1509
1510static int pl022_prepare_transfer_hardware(struct spi_master *master)
1511{
1512 struct pl022 *pl022 = spi_master_get_devdata(master);
1513
1514 /*
1515 * Just make sure we have all we need to run the transfer by syncing
1516 * with the runtime PM framework.
1517 */
1518 pm_runtime_get_sync(&pl022->adev->dev);
1519 return 0;
1520}
1521
1522static int pl022_unprepare_transfer_hardware(struct spi_master *master)
1523{
1524 struct pl022 *pl022 = spi_master_get_devdata(master);
1525
1526 /* nothing more to do - disable spi/ssp and power off */
1527 writew((readw(SSP_CR1(pl022->virtbase)) &
1528 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1529
1530 if (pl022->master_info->autosuspend_delay > 0) {
1531 pm_runtime_mark_last_busy(&pl022->adev->dev);
1532 pm_runtime_put_autosuspend(&pl022->adev->dev);
1533 } else {
1534 pm_runtime_put(&pl022->adev->dev);
1535 }
1536
1537 return 0;
1538}
1539
1540static int verify_controller_parameters(struct pl022 *pl022,
1541 struct pl022_config_chip const *chip_info)
1542{
1543 if ((chip_info->iface < SSP_INTERFACE_MOTOROLA_SPI)
1544 || (chip_info->iface > SSP_INTERFACE_UNIDIRECTIONAL)) {
1545 dev_err(&pl022->adev->dev,
1546 "interface is configured incorrectly\n");
1547 return -EINVAL;
1548 }
1549 if ((chip_info->iface == SSP_INTERFACE_UNIDIRECTIONAL) &&
1550 (!pl022->vendor->unidir)) {
1551 dev_err(&pl022->adev->dev,
1552 "unidirectional mode not supported in this "
1553 "hardware version\n");
1554 return -EINVAL;
1555 }
1556 if ((chip_info->hierarchy != SSP_MASTER)
1557 && (chip_info->hierarchy != SSP_SLAVE)) {
1558 dev_err(&pl022->adev->dev,
1559 "hierarchy is configured incorrectly\n");
1560 return -EINVAL;
1561 }
1562 if ((chip_info->com_mode != INTERRUPT_TRANSFER)
1563 && (chip_info->com_mode != DMA_TRANSFER)
1564 && (chip_info->com_mode != POLLING_TRANSFER)) {
1565 dev_err(&pl022->adev->dev,
1566 "Communication mode is configured incorrectly\n");
1567 return -EINVAL;
1568 }
1569 switch (chip_info->rx_lev_trig) {
1570 case SSP_RX_1_OR_MORE_ELEM:
1571 case SSP_RX_4_OR_MORE_ELEM:
1572 case SSP_RX_8_OR_MORE_ELEM:
1573 /* These are always OK, all variants can handle this */
1574 break;
1575 case SSP_RX_16_OR_MORE_ELEM:
1576 if (pl022->vendor->fifodepth < 16) {
1577 dev_err(&pl022->adev->dev,
1578 "RX FIFO Trigger Level is configured incorrectly\n");
1579 return -EINVAL;
1580 }
1581 break;
1582 case SSP_RX_32_OR_MORE_ELEM:
1583 if (pl022->vendor->fifodepth < 32) {
1584 dev_err(&pl022->adev->dev,
1585 "RX FIFO Trigger Level is configured incorrectly\n");
1586 return -EINVAL;
1587 }
1588 break;
1589 default:
1590 dev_err(&pl022->adev->dev,
1591 "RX FIFO Trigger Level is configured incorrectly\n");
1592 return -EINVAL;
1593 break;
1594 }
1595 switch (chip_info->tx_lev_trig) {
1596 case SSP_TX_1_OR_MORE_EMPTY_LOC:
1597 case SSP_TX_4_OR_MORE_EMPTY_LOC:
1598 case SSP_TX_8_OR_MORE_EMPTY_LOC:
1599 /* These are always OK, all variants can handle this */
1600 break;
1601 case SSP_TX_16_OR_MORE_EMPTY_LOC:
1602 if (pl022->vendor->fifodepth < 16) {
1603 dev_err(&pl022->adev->dev,
1604 "TX FIFO Trigger Level is configured incorrectly\n");
1605 return -EINVAL;
1606 }
1607 break;
1608 case SSP_TX_32_OR_MORE_EMPTY_LOC:
1609 if (pl022->vendor->fifodepth < 32) {
1610 dev_err(&pl022->adev->dev,
1611 "TX FIFO Trigger Level is configured incorrectly\n");
1612 return -EINVAL;
1613 }
1614 break;
1615 default:
1616 dev_err(&pl022->adev->dev,
1617 "TX FIFO Trigger Level is configured incorrectly\n");
1618 return -EINVAL;
1619 break;
1620 }
1621 if (chip_info->iface == SSP_INTERFACE_NATIONAL_MICROWIRE) {
1622 if ((chip_info->ctrl_len < SSP_BITS_4)
1623 || (chip_info->ctrl_len > SSP_BITS_32)) {
1624 dev_err(&pl022->adev->dev,
1625 "CTRL LEN is configured incorrectly\n");
1626 return -EINVAL;
1627 }
1628 if ((chip_info->wait_state != SSP_MWIRE_WAIT_ZERO)
1629 && (chip_info->wait_state != SSP_MWIRE_WAIT_ONE)) {
1630 dev_err(&pl022->adev->dev,
1631 "Wait State is configured incorrectly\n");
1632 return -EINVAL;
1633 }
1634 /* Half duplex is only available in the ST Micro version */
1635 if (pl022->vendor->extended_cr) {
1636 if ((chip_info->duplex !=
1637 SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
1638 && (chip_info->duplex !=
1639 SSP_MICROWIRE_CHANNEL_HALF_DUPLEX)) {
1640 dev_err(&pl022->adev->dev,
1641 "Microwire duplex mode is configured incorrectly\n");
1642 return -EINVAL;
1643 }
1644 } else {
1645 if (chip_info->duplex != SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
1646 dev_err(&pl022->adev->dev,
1647 "Microwire half duplex mode requested,"
1648 " but this is only available in the"
1649 " ST version of PL022\n");
1650 return -EINVAL;
1651 }
1652 }
1653 return 0;
1654}
1655
1656static inline u32 spi_rate(u32 rate, u16 cpsdvsr, u16 scr)
1657{
1658 return rate / (cpsdvsr * (1 + scr));
1659}
1660
1661static int calculate_effective_freq(struct pl022 *pl022, int freq, struct
1662 ssp_clock_params * clk_freq)
1663{
1664 /* Lets calculate the frequency parameters */
1665 u16 cpsdvsr = CPSDVR_MIN, scr = SCR_MIN;
1666 u32 rate, max_tclk, min_tclk, best_freq = 0, best_cpsdvsr = 0,
1667 best_scr = 0, tmp, found = 0;
1668
1669 rate = clk_get_rate(pl022->clk);
1670 /* cpsdvscr = 2 & scr 0 */
1671 max_tclk = spi_rate(rate, CPSDVR_MIN, SCR_MIN);
1672 /* cpsdvsr = 254 & scr = 255 */
1673 min_tclk = spi_rate(rate, CPSDVR_MAX, SCR_MAX);
1674
1675 if (freq > max_tclk)
1676 dev_warn(&pl022->adev->dev,
1677 "Max speed that can be programmed is %d Hz, you requested %d\n",
1678 max_tclk, freq);
1679
1680 if (freq < min_tclk) {
1681 dev_err(&pl022->adev->dev,
1682 "Requested frequency: %d Hz is less than minimum possible %d Hz\n",
1683 freq, min_tclk);
1684 return -EINVAL;
1685 }
1686
1687 /*
1688 * best_freq will give closest possible available rate (<= requested
1689 * freq) for all values of scr & cpsdvsr.
1690 */
1691 while ((cpsdvsr <= CPSDVR_MAX) && !found) {
1692 while (scr <= SCR_MAX) {
1693 tmp = spi_rate(rate, cpsdvsr, scr);
1694
1695 if (tmp > freq) {
1696 /* we need lower freq */
1697 scr++;
1698 continue;
1699 }
1700
1701 /*
1702 * If found exact value, mark found and break.
1703 * If found more closer value, update and break.
1704 */
1705 if (tmp > best_freq) {
1706 best_freq = tmp;
1707 best_cpsdvsr = cpsdvsr;
1708 best_scr = scr;
1709
1710 if (tmp == freq)
1711 found = 1;
1712 }
1713 /*
1714 * increased scr will give lower rates, which are not
1715 * required
1716 */
1717 break;
1718 }
1719 cpsdvsr += 2;
1720 scr = SCR_MIN;
1721 }
1722
1723 WARN(!best_freq, "pl022: Matching cpsdvsr and scr not found for %d Hz rate \n",
1724 freq);
1725
1726 clk_freq->cpsdvsr = (u8) (best_cpsdvsr & 0xFF);
1727 clk_freq->scr = (u8) (best_scr & 0xFF);
1728 dev_dbg(&pl022->adev->dev,
1729 "SSP Target Frequency is: %u, Effective Frequency is %u\n",
1730 freq, best_freq);
1731 dev_dbg(&pl022->adev->dev, "SSP cpsdvsr = %d, scr = %d\n",
1732 clk_freq->cpsdvsr, clk_freq->scr);
1733
1734 return 0;
1735}
1736
1737/*
1738 * A piece of default chip info unless the platform
1739 * supplies it.
1740 */
1741static const struct pl022_config_chip pl022_default_chip_info = {
1742 .com_mode = POLLING_TRANSFER,
1743 .iface = SSP_INTERFACE_MOTOROLA_SPI,
1744 .hierarchy = SSP_SLAVE,
1745 .slave_tx_disable = DO_NOT_DRIVE_TX,
1746 .rx_lev_trig = SSP_RX_1_OR_MORE_ELEM,
1747 .tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC,
1748 .ctrl_len = SSP_BITS_8,
1749 .wait_state = SSP_MWIRE_WAIT_ZERO,
1750 .duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX,
1751 .cs_control = null_cs_control,
1752};
1753
1754/**
1755 * pl022_setup - setup function registered to SPI master framework
1756 * @spi: spi device which is requesting setup
1757 *
1758 * This function is registered to the SPI framework for this SPI master
1759 * controller. If it is the first time when setup is called by this device,
1760 * this function will initialize the runtime state for this chip and save
1761 * the same in the device structure. Else it will update the runtime info
1762 * with the updated chip info. Nothing is really being written to the
1763 * controller hardware here, that is not done until the actual transfer
1764 * commence.
1765 */
1766static int pl022_setup(struct spi_device *spi)
1767{
1768 struct pl022_config_chip const *chip_info;
1769 struct chip_data *chip;
1770 struct ssp_clock_params clk_freq = { .cpsdvsr = 0, .scr = 0};
1771 int status = 0;
1772 struct pl022 *pl022 = spi_master_get_devdata(spi->master);
1773 unsigned int bits = spi->bits_per_word;
1774 u32 tmp;
1775
1776 if (!spi->max_speed_hz)
1777 return -EINVAL;
1778
1779 /* Get controller_state if one is supplied */
1780 chip = spi_get_ctldata(spi);
1781
1782 if (chip == NULL) {
1783 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
1784 if (!chip) {
1785 dev_err(&spi->dev,
1786 "cannot allocate controller state\n");
1787 return -ENOMEM;
1788 }
1789 dev_dbg(&spi->dev,
1790 "allocated memory for controller's runtime state\n");
1791 }
1792
1793 /* Get controller data if one is supplied */
1794 chip_info = spi->controller_data;
1795
1796 if (chip_info == NULL) {
1797 chip_info = &pl022_default_chip_info;
1798 /* spi_board_info.controller_data not is supplied */
1799 dev_dbg(&spi->dev,
1800 "using default controller_data settings\n");
1801 } else
1802 dev_dbg(&spi->dev,
1803 "using user supplied controller_data settings\n");
1804
1805 /*
1806 * We can override with custom divisors, else we use the board
1807 * frequency setting
1808 */
1809 if ((0 == chip_info->clk_freq.cpsdvsr)
1810 && (0 == chip_info->clk_freq.scr)) {
1811 status = calculate_effective_freq(pl022,
1812 spi->max_speed_hz,
1813 &clk_freq);
1814 if (status < 0)
1815 goto err_config_params;
1816 } else {
1817 memcpy(&clk_freq, &chip_info->clk_freq, sizeof(clk_freq));
1818 if ((clk_freq.cpsdvsr % 2) != 0)
1819 clk_freq.cpsdvsr =
1820 clk_freq.cpsdvsr - 1;
1821 }
1822 if ((clk_freq.cpsdvsr < CPSDVR_MIN)
1823 || (clk_freq.cpsdvsr > CPSDVR_MAX)) {
1824 status = -EINVAL;
1825 dev_err(&spi->dev,
1826 "cpsdvsr is configured incorrectly\n");
1827 goto err_config_params;
1828 }
1829
1830 status = verify_controller_parameters(pl022, chip_info);
1831 if (status) {
1832 dev_err(&spi->dev, "controller data is incorrect");
1833 goto err_config_params;
1834 }
1835
1836 pl022->rx_lev_trig = chip_info->rx_lev_trig;
1837 pl022->tx_lev_trig = chip_info->tx_lev_trig;
1838
1839 /* Now set controller state based on controller data */
1840 chip->xfer_type = chip_info->com_mode;
1841 if (!chip_info->cs_control) {
1842 chip->cs_control = null_cs_control;
1843 dev_warn(&spi->dev,
1844 "chip select function is NULL for this chip\n");
1845 } else
1846 chip->cs_control = chip_info->cs_control;
1847
1848 /* Check bits per word with vendor specific range */
1849 if ((bits <= 3) || (bits > pl022->vendor->max_bpw)) {
1850 status = -ENOTSUPP;
1851 dev_err(&spi->dev, "illegal data size for this controller!\n");
1852 dev_err(&spi->dev, "This controller can only handle 4 <= n <= %d bit words\n",
1853 pl022->vendor->max_bpw);
1854 goto err_config_params;
1855 } else if (bits <= 8) {
1856 dev_dbg(&spi->dev, "4 <= n <=8 bits per word\n");
1857 chip->n_bytes = 1;
1858 chip->read = READING_U8;
1859 chip->write = WRITING_U8;
1860 } else if (bits <= 16) {
1861 dev_dbg(&spi->dev, "9 <= n <= 16 bits per word\n");
1862 chip->n_bytes = 2;
1863 chip->read = READING_U16;
1864 chip->write = WRITING_U16;
1865 } else {
1866 dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n");
1867 chip->n_bytes = 4;
1868 chip->read = READING_U32;
1869 chip->write = WRITING_U32;
1870 }
1871
1872 /* Now Initialize all register settings required for this chip */
1873 chip->cr0 = 0;
1874 chip->cr1 = 0;
1875 chip->dmacr = 0;
1876 chip->cpsr = 0;
1877 if ((chip_info->com_mode == DMA_TRANSFER)
1878 && ((pl022->master_info)->enable_dma)) {
1879 chip->enable_dma = true;
1880 dev_dbg(&spi->dev, "DMA mode set in controller state\n");
1881 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
1882 SSP_DMACR_MASK_RXDMAE, 0);
1883 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
1884 SSP_DMACR_MASK_TXDMAE, 1);
1885 } else {
1886 chip->enable_dma = false;
1887 dev_dbg(&spi->dev, "DMA mode NOT set in controller state\n");
1888 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
1889 SSP_DMACR_MASK_RXDMAE, 0);
1890 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
1891 SSP_DMACR_MASK_TXDMAE, 1);
1892 }
1893
1894 chip->cpsr = clk_freq.cpsdvsr;
1895
1896 /* Special setup for the ST micro extended control registers */
1897 if (pl022->vendor->extended_cr) {
1898 u32 etx;
1899
1900 if (pl022->vendor->pl023) {
1901 /* These bits are only in the PL023 */
1902 SSP_WRITE_BITS(chip->cr1, chip_info->clkdelay,
1903 SSP_CR1_MASK_FBCLKDEL_ST, 13);
1904 } else {
1905 /* These bits are in the PL022 but not PL023 */
1906 SSP_WRITE_BITS(chip->cr0, chip_info->duplex,
1907 SSP_CR0_MASK_HALFDUP_ST, 5);
1908 SSP_WRITE_BITS(chip->cr0, chip_info->ctrl_len,
1909 SSP_CR0_MASK_CSS_ST, 16);
1910 SSP_WRITE_BITS(chip->cr0, chip_info->iface,
1911 SSP_CR0_MASK_FRF_ST, 21);
1912 SSP_WRITE_BITS(chip->cr1, chip_info->wait_state,
1913 SSP_CR1_MASK_MWAIT_ST, 6);
1914 }
1915 SSP_WRITE_BITS(chip->cr0, bits - 1,
1916 SSP_CR0_MASK_DSS_ST, 0);
1917
1918 if (spi->mode & SPI_LSB_FIRST) {
1919 tmp = SSP_RX_LSB;
1920 etx = SSP_TX_LSB;
1921 } else {
1922 tmp = SSP_RX_MSB;
1923 etx = SSP_TX_MSB;
1924 }
1925 SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_RENDN_ST, 4);
1926 SSP_WRITE_BITS(chip->cr1, etx, SSP_CR1_MASK_TENDN_ST, 5);
1927 SSP_WRITE_BITS(chip->cr1, chip_info->rx_lev_trig,
1928 SSP_CR1_MASK_RXIFLSEL_ST, 7);
1929 SSP_WRITE_BITS(chip->cr1, chip_info->tx_lev_trig,
1930 SSP_CR1_MASK_TXIFLSEL_ST, 10);
1931 } else {
1932 SSP_WRITE_BITS(chip->cr0, bits - 1,
1933 SSP_CR0_MASK_DSS, 0);
1934 SSP_WRITE_BITS(chip->cr0, chip_info->iface,
1935 SSP_CR0_MASK_FRF, 4);
1936 }
1937
1938 /* Stuff that is common for all versions */
1939 if (spi->mode & SPI_CPOL)
1940 tmp = SSP_CLK_POL_IDLE_HIGH;
1941 else
1942 tmp = SSP_CLK_POL_IDLE_LOW;
1943 SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPO, 6);
1944
1945 if (spi->mode & SPI_CPHA)
1946 tmp = SSP_CLK_SECOND_EDGE;
1947 else
1948 tmp = SSP_CLK_FIRST_EDGE;
1949 SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPH, 7);
1950
1951 SSP_WRITE_BITS(chip->cr0, clk_freq.scr, SSP_CR0_MASK_SCR, 8);
1952 /* Loopback is available on all versions except PL023 */
1953 if (pl022->vendor->loopback) {
1954 if (spi->mode & SPI_LOOP)
1955 tmp = LOOPBACK_ENABLED;
1956 else
1957 tmp = LOOPBACK_DISABLED;
1958 SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_LBM, 0);
1959 }
1960 SSP_WRITE_BITS(chip->cr1, SSP_DISABLED, SSP_CR1_MASK_SSE, 1);
1961 SSP_WRITE_BITS(chip->cr1, chip_info->hierarchy, SSP_CR1_MASK_MS, 2);
1962 SSP_WRITE_BITS(chip->cr1, chip_info->slave_tx_disable, SSP_CR1_MASK_SOD,
1963 3);
1964
1965 /* Save controller_state */
1966 spi_set_ctldata(spi, chip);
1967 return status;
1968 err_config_params:
1969 spi_set_ctldata(spi, NULL);
1970 kfree(chip);
1971 return status;
1972}
1973
1974/**
1975 * pl022_cleanup - cleanup function registered to SPI master framework
1976 * @spi: spi device which is requesting cleanup
1977 *
1978 * This function is registered to the SPI framework for this SPI master
1979 * controller. It will free the runtime state of chip.
1980 */
1981static void pl022_cleanup(struct spi_device *spi)
1982{
1983 struct chip_data *chip = spi_get_ctldata(spi);
1984
1985 spi_set_ctldata(spi, NULL);
1986 kfree(chip);
1987}
1988
1989static int __devinit
1990pl022_probe(struct amba_device *adev, const struct amba_id *id)
1991{
1992 struct device *dev = &adev->dev;
1993 struct pl022_ssp_controller *platform_info = adev->dev.platform_data;
1994 struct spi_master *master;
1995 struct pl022 *pl022 = NULL; /*Data for this driver */
1996 int status = 0;
1997
1998 dev_info(&adev->dev,
1999 "ARM PL022 driver, device ID: 0x%08x\n", adev->periphid);
2000 if (platform_info == NULL) {
2001 dev_err(&adev->dev, "probe - no platform data supplied\n");
2002 status = -ENODEV;
2003 goto err_no_pdata;
2004 }
2005
2006 /* Allocate master with space for data */
2007 master = spi_alloc_master(dev, sizeof(struct pl022));
2008 if (master == NULL) {
2009 dev_err(&adev->dev, "probe - cannot alloc SPI master\n");
2010 status = -ENOMEM;
2011 goto err_no_master;
2012 }
2013
2014 pl022 = spi_master_get_devdata(master);
2015 pl022->master = master;
2016 pl022->master_info = platform_info;
2017 pl022->adev = adev;
2018 pl022->vendor = id->data;
2019
2020 /*
2021 * Bus Number Which has been Assigned to this SSP controller
2022 * on this board
2023 */
2024 master->bus_num = platform_info->bus_id;
2025 master->num_chipselect = platform_info->num_chipselect;
2026 master->cleanup = pl022_cleanup;
2027 master->setup = pl022_setup;
2028 master->prepare_transfer_hardware = pl022_prepare_transfer_hardware;
2029 master->transfer_one_message = pl022_transfer_one_message;
2030 master->unprepare_transfer_hardware = pl022_unprepare_transfer_hardware;
2031 master->rt = platform_info->rt;
2032
2033 /*
2034 * Supports mode 0-3, loopback, and active low CS. Transfers are
2035 * always MS bit first on the original pl022.
2036 */
2037 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
2038 if (pl022->vendor->extended_cr)
2039 master->mode_bits |= SPI_LSB_FIRST;
2040
2041 dev_dbg(&adev->dev, "BUSNO: %d\n", master->bus_num);
2042
2043 status = amba_request_regions(adev, NULL);
2044 if (status)
2045 goto err_no_ioregion;
2046
2047 pl022->phybase = adev->res.start;
2048 pl022->virtbase = ioremap(adev->res.start, resource_size(&adev->res));
2049 if (pl022->virtbase == NULL) {
2050 status = -ENOMEM;
2051 goto err_no_ioremap;
2052 }
2053 printk(KERN_INFO "pl022: mapped registers from 0x%08x to %p\n",
2054 adev->res.start, pl022->virtbase);
2055
2056 pl022->clk = clk_get(&adev->dev, NULL);
2057 if (IS_ERR(pl022->clk)) {
2058 status = PTR_ERR(pl022->clk);
2059 dev_err(&adev->dev, "could not retrieve SSP/SPI bus clock\n");
2060 goto err_no_clk;
2061 }
2062
2063 status = clk_prepare(pl022->clk);
2064 if (status) {
2065 dev_err(&adev->dev, "could not prepare SSP/SPI bus clock\n");
2066 goto err_clk_prep;
2067 }
2068
2069 status = clk_enable(pl022->clk);
2070 if (status) {
2071 dev_err(&adev->dev, "could not enable SSP/SPI bus clock\n");
2072 goto err_no_clk_en;
2073 }
2074
2075 /* Initialize transfer pump */
2076 tasklet_init(&pl022->pump_transfers, pump_transfers,
2077 (unsigned long)pl022);
2078
2079 /* Disable SSP */
2080 writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)),
2081 SSP_CR1(pl022->virtbase));
2082 load_ssp_default_config(pl022);
2083
2084 status = request_irq(adev->irq[0], pl022_interrupt_handler, 0, "pl022",
2085 pl022);
2086 if (status < 0) {
2087 dev_err(&adev->dev, "probe - cannot get IRQ (%d)\n", status);
2088 goto err_no_irq;
2089 }
2090
2091 /* Get DMA channels */
2092 if (platform_info->enable_dma) {
2093 status = pl022_dma_probe(pl022);
2094 if (status != 0)
2095 platform_info->enable_dma = 0;
2096 }
2097
2098 /* Register with the SPI framework */
2099 amba_set_drvdata(adev, pl022);
2100 status = spi_register_master(master);
2101 if (status != 0) {
2102 dev_err(&adev->dev,
2103 "probe - problem registering spi master\n");
2104 goto err_spi_register;
2105 }
2106 dev_dbg(dev, "probe succeeded\n");
2107
2108 /* let runtime pm put suspend */
2109 if (platform_info->autosuspend_delay > 0) {
2110 dev_info(&adev->dev,
2111 "will use autosuspend for runtime pm, delay %dms\n",
2112 platform_info->autosuspend_delay);
2113 pm_runtime_set_autosuspend_delay(dev,
2114 platform_info->autosuspend_delay);
2115 pm_runtime_use_autosuspend(dev);
2116 pm_runtime_put_autosuspend(dev);
2117 } else {
2118 pm_runtime_put(dev);
2119 }
2120 return 0;
2121
2122 err_spi_register:
2123 if (platform_info->enable_dma)
2124 pl022_dma_remove(pl022);
2125
2126 free_irq(adev->irq[0], pl022);
2127 err_no_irq:
2128 clk_disable(pl022->clk);
2129 err_no_clk_en:
2130 clk_unprepare(pl022->clk);
2131 err_clk_prep:
2132 clk_put(pl022->clk);
2133 err_no_clk:
2134 iounmap(pl022->virtbase);
2135 err_no_ioremap:
2136 amba_release_regions(adev);
2137 err_no_ioregion:
2138 spi_master_put(master);
2139 err_no_master:
2140 err_no_pdata:
2141 return status;
2142}
2143
2144static int __devexit
2145pl022_remove(struct amba_device *adev)
2146{
2147 struct pl022 *pl022 = amba_get_drvdata(adev);
2148
2149 if (!pl022)
2150 return 0;
2151
2152 /*
2153 * undo pm_runtime_put() in probe. I assume that we're not
2154 * accessing the primecell here.
2155 */
2156 pm_runtime_get_noresume(&adev->dev);
2157
2158 load_ssp_default_config(pl022);
2159 if (pl022->master_info->enable_dma)
2160 pl022_dma_remove(pl022);
2161
2162 free_irq(adev->irq[0], pl022);
2163 clk_disable(pl022->clk);
2164 clk_unprepare(pl022->clk);
2165 clk_put(pl022->clk);
2166 iounmap(pl022->virtbase);
2167 amba_release_regions(adev);
2168 tasklet_disable(&pl022->pump_transfers);
2169 spi_unregister_master(pl022->master);
2170 spi_master_put(pl022->master);
2171 amba_set_drvdata(adev, NULL);
2172 return 0;
2173}
2174
2175#ifdef CONFIG_SUSPEND
2176static int pl022_suspend(struct device *dev)
2177{
2178 struct pl022 *pl022 = dev_get_drvdata(dev);
2179 int ret;
2180
2181 ret = spi_master_suspend(pl022->master);
2182 if (ret) {
2183 dev_warn(dev, "cannot suspend master\n");
2184 return ret;
2185 }
2186
2187 dev_dbg(dev, "suspended\n");
2188 return 0;
2189}
2190
2191static int pl022_resume(struct device *dev)
2192{
2193 struct pl022 *pl022 = dev_get_drvdata(dev);
2194 int ret;
2195
2196 /* Start the queue running */
2197 ret = spi_master_resume(pl022->master);
2198 if (ret)
2199 dev_err(dev, "problem starting queue (%d)\n", ret);
2200 else
2201 dev_dbg(dev, "resumed\n");
2202
2203 return ret;
2204}
2205#endif /* CONFIG_PM */
2206
2207#ifdef CONFIG_PM_RUNTIME
2208static int pl022_runtime_suspend(struct device *dev)
2209{
2210 struct pl022 *pl022 = dev_get_drvdata(dev);
2211
2212 clk_disable(pl022->clk);
2213
2214 return 0;
2215}
2216
2217static int pl022_runtime_resume(struct device *dev)
2218{
2219 struct pl022 *pl022 = dev_get_drvdata(dev);
2220
2221 clk_enable(pl022->clk);
2222
2223 return 0;
2224}
2225#endif
2226
2227static const struct dev_pm_ops pl022_dev_pm_ops = {
2228 SET_SYSTEM_SLEEP_PM_OPS(pl022_suspend, pl022_resume)
2229 SET_RUNTIME_PM_OPS(pl022_runtime_suspend, pl022_runtime_resume, NULL)
2230};
2231
2232static struct vendor_data vendor_arm = {
2233 .fifodepth = 8,
2234 .max_bpw = 16,
2235 .unidir = false,
2236 .extended_cr = false,
2237 .pl023 = false,
2238 .loopback = true,
2239};
2240
2241static struct vendor_data vendor_st = {
2242 .fifodepth = 32,
2243 .max_bpw = 32,
2244 .unidir = false,
2245 .extended_cr = true,
2246 .pl023 = false,
2247 .loopback = true,
2248};
2249
2250static struct vendor_data vendor_st_pl023 = {
2251 .fifodepth = 32,
2252 .max_bpw = 32,
2253 .unidir = false,
2254 .extended_cr = true,
2255 .pl023 = true,
2256 .loopback = false,
2257};
2258
2259static struct vendor_data vendor_db5500_pl023 = {
2260 .fifodepth = 32,
2261 .max_bpw = 32,
2262 .unidir = false,
2263 .extended_cr = true,
2264 .pl023 = true,
2265 .loopback = true,
2266};
2267
2268static struct amba_id pl022_ids[] = {
2269 {
2270 /*
2271 * ARM PL022 variant, this has a 16bit wide
2272 * and 8 locations deep TX/RX FIFO
2273 */
2274 .id = 0x00041022,
2275 .mask = 0x000fffff,
2276 .data = &vendor_arm,
2277 },
2278 {
2279 /*
2280 * ST Micro derivative, this has 32bit wide
2281 * and 32 locations deep TX/RX FIFO
2282 */
2283 .id = 0x01080022,
2284 .mask = 0xffffffff,
2285 .data = &vendor_st,
2286 },
2287 {
2288 /*
2289 * ST-Ericsson derivative "PL023" (this is not
2290 * an official ARM number), this is a PL022 SSP block
2291 * stripped to SPI mode only, it has 32bit wide
2292 * and 32 locations deep TX/RX FIFO but no extended
2293 * CR0/CR1 register
2294 */
2295 .id = 0x00080023,
2296 .mask = 0xffffffff,
2297 .data = &vendor_st_pl023,
2298 },
2299 {
2300 .id = 0x10080023,
2301 .mask = 0xffffffff,
2302 .data = &vendor_db5500_pl023,
2303 },
2304 { 0, 0 },
2305};
2306
2307MODULE_DEVICE_TABLE(amba, pl022_ids);
2308
2309static struct amba_driver pl022_driver = {
2310 .drv = {
2311 .name = "ssp-pl022",
2312 .pm = &pl022_dev_pm_ops,
2313 },
2314 .id_table = pl022_ids,
2315 .probe = pl022_probe,
2316 .remove = __devexit_p(pl022_remove),
2317};
2318
2319static int __init pl022_init(void)
2320{
2321 return amba_driver_register(&pl022_driver);
2322}
2323subsys_initcall(pl022_init);
2324
2325static void __exit pl022_exit(void)
2326{
2327 amba_driver_unregister(&pl022_driver);
2328}
2329module_exit(pl022_exit);
2330
2331MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
2332MODULE_DESCRIPTION("PL022 SSP Controller Driver");
2333MODULE_LICENSE("GPL");