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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * SH RSPI driver
4 *
5 * Copyright (C) 2012, 2013 Renesas Solutions Corp.
6 * Copyright (C) 2014 Glider bvba
7 *
8 * Based on spi-sh.c:
9 * Copyright (C) 2011 Renesas Solutions Corp.
10 */
11
12#include <linux/module.h>
13#include <linux/kernel.h>
14#include <linux/sched.h>
15#include <linux/errno.h>
16#include <linux/interrupt.h>
17#include <linux/platform_device.h>
18#include <linux/io.h>
19#include <linux/clk.h>
20#include <linux/dmaengine.h>
21#include <linux/dma-mapping.h>
22#include <linux/of.h>
23#include <linux/pm_runtime.h>
24#include <linux/reset.h>
25#include <linux/sh_dma.h>
26#include <linux/spi/spi.h>
27#include <linux/spi/rspi.h>
28#include <linux/spinlock.h>
29
30#define RSPI_SPCR 0x00 /* Control Register */
31#define RSPI_SSLP 0x01 /* Slave Select Polarity Register */
32#define RSPI_SPPCR 0x02 /* Pin Control Register */
33#define RSPI_SPSR 0x03 /* Status Register */
34#define RSPI_SPDR 0x04 /* Data Register */
35#define RSPI_SPSCR 0x08 /* Sequence Control Register */
36#define RSPI_SPSSR 0x09 /* Sequence Status Register */
37#define RSPI_SPBR 0x0a /* Bit Rate Register */
38#define RSPI_SPDCR 0x0b /* Data Control Register */
39#define RSPI_SPCKD 0x0c /* Clock Delay Register */
40#define RSPI_SSLND 0x0d /* Slave Select Negation Delay Register */
41#define RSPI_SPND 0x0e /* Next-Access Delay Register */
42#define RSPI_SPCR2 0x0f /* Control Register 2 (SH only) */
43#define RSPI_SPCMD0 0x10 /* Command Register 0 */
44#define RSPI_SPCMD1 0x12 /* Command Register 1 */
45#define RSPI_SPCMD2 0x14 /* Command Register 2 */
46#define RSPI_SPCMD3 0x16 /* Command Register 3 */
47#define RSPI_SPCMD4 0x18 /* Command Register 4 */
48#define RSPI_SPCMD5 0x1a /* Command Register 5 */
49#define RSPI_SPCMD6 0x1c /* Command Register 6 */
50#define RSPI_SPCMD7 0x1e /* Command Register 7 */
51#define RSPI_SPCMD(i) (RSPI_SPCMD0 + (i) * 2)
52#define RSPI_NUM_SPCMD 8
53#define RSPI_RZ_NUM_SPCMD 4
54#define QSPI_NUM_SPCMD 4
55
56/* RSPI on RZ only */
57#define RSPI_SPBFCR 0x20 /* Buffer Control Register */
58#define RSPI_SPBFDR 0x22 /* Buffer Data Count Setting Register */
59
60/* QSPI only */
61#define QSPI_SPBFCR 0x18 /* Buffer Control Register */
62#define QSPI_SPBDCR 0x1a /* Buffer Data Count Register */
63#define QSPI_SPBMUL0 0x1c /* Transfer Data Length Multiplier Setting Register 0 */
64#define QSPI_SPBMUL1 0x20 /* Transfer Data Length Multiplier Setting Register 1 */
65#define QSPI_SPBMUL2 0x24 /* Transfer Data Length Multiplier Setting Register 2 */
66#define QSPI_SPBMUL3 0x28 /* Transfer Data Length Multiplier Setting Register 3 */
67#define QSPI_SPBMUL(i) (QSPI_SPBMUL0 + (i) * 4)
68
69/* SPCR - Control Register */
70#define SPCR_SPRIE 0x80 /* Receive Interrupt Enable */
71#define SPCR_SPE 0x40 /* Function Enable */
72#define SPCR_SPTIE 0x20 /* Transmit Interrupt Enable */
73#define SPCR_SPEIE 0x10 /* Error Interrupt Enable */
74#define SPCR_MSTR 0x08 /* Master/Slave Mode Select */
75#define SPCR_MODFEN 0x04 /* Mode Fault Error Detection Enable */
76/* RSPI on SH only */
77#define SPCR_TXMD 0x02 /* TX Only Mode (vs. Full Duplex) */
78#define SPCR_SPMS 0x01 /* 3-wire Mode (vs. 4-wire) */
79/* QSPI on R-Car Gen2 only */
80#define SPCR_WSWAP 0x02 /* Word Swap of read-data for DMAC */
81#define SPCR_BSWAP 0x01 /* Byte Swap of read-data for DMAC */
82
83/* SSLP - Slave Select Polarity Register */
84#define SSLP_SSLP(i) BIT(i) /* SSLi Signal Polarity Setting */
85
86/* SPPCR - Pin Control Register */
87#define SPPCR_MOIFE 0x20 /* MOSI Idle Value Fixing Enable */
88#define SPPCR_MOIFV 0x10 /* MOSI Idle Fixed Value */
89#define SPPCR_SPOM 0x04
90#define SPPCR_SPLP2 0x02 /* Loopback Mode 2 (non-inverting) */
91#define SPPCR_SPLP 0x01 /* Loopback Mode (inverting) */
92
93#define SPPCR_IO3FV 0x04 /* Single-/Dual-SPI Mode IO3 Output Fixed Value */
94#define SPPCR_IO2FV 0x04 /* Single-/Dual-SPI Mode IO2 Output Fixed Value */
95
96/* SPSR - Status Register */
97#define SPSR_SPRF 0x80 /* Receive Buffer Full Flag */
98#define SPSR_TEND 0x40 /* Transmit End */
99#define SPSR_SPTEF 0x20 /* Transmit Buffer Empty Flag */
100#define SPSR_PERF 0x08 /* Parity Error Flag */
101#define SPSR_MODF 0x04 /* Mode Fault Error Flag */
102#define SPSR_IDLNF 0x02 /* RSPI Idle Flag */
103#define SPSR_OVRF 0x01 /* Overrun Error Flag (RSPI only) */
104
105/* SPSCR - Sequence Control Register */
106#define SPSCR_SPSLN_MASK 0x07 /* Sequence Length Specification */
107
108/* SPSSR - Sequence Status Register */
109#define SPSSR_SPECM_MASK 0x70 /* Command Error Mask */
110#define SPSSR_SPCP_MASK 0x07 /* Command Pointer Mask */
111
112/* SPDCR - Data Control Register */
113#define SPDCR_TXDMY 0x80 /* Dummy Data Transmission Enable */
114#define SPDCR_SPLW1 0x40 /* Access Width Specification (RZ) */
115#define SPDCR_SPLW0 0x20 /* Access Width Specification (RZ) */
116#define SPDCR_SPLLWORD (SPDCR_SPLW1 | SPDCR_SPLW0)
117#define SPDCR_SPLWORD SPDCR_SPLW1
118#define SPDCR_SPLBYTE SPDCR_SPLW0
119#define SPDCR_SPLW 0x20 /* Access Width Specification (SH) */
120#define SPDCR_SPRDTD 0x10 /* Receive Transmit Data Select (SH) */
121#define SPDCR_SLSEL1 0x08
122#define SPDCR_SLSEL0 0x04
123#define SPDCR_SLSEL_MASK 0x0c /* SSL1 Output Select (SH) */
124#define SPDCR_SPFC1 0x02
125#define SPDCR_SPFC0 0x01
126#define SPDCR_SPFC_MASK 0x03 /* Frame Count Setting (1-4) (SH) */
127
128/* SPCKD - Clock Delay Register */
129#define SPCKD_SCKDL_MASK 0x07 /* Clock Delay Setting (1-8) */
130
131/* SSLND - Slave Select Negation Delay Register */
132#define SSLND_SLNDL_MASK 0x07 /* SSL Negation Delay Setting (1-8) */
133
134/* SPND - Next-Access Delay Register */
135#define SPND_SPNDL_MASK 0x07 /* Next-Access Delay Setting (1-8) */
136
137/* SPCR2 - Control Register 2 */
138#define SPCR2_PTE 0x08 /* Parity Self-Test Enable */
139#define SPCR2_SPIE 0x04 /* Idle Interrupt Enable */
140#define SPCR2_SPOE 0x02 /* Odd Parity Enable (vs. Even) */
141#define SPCR2_SPPE 0x01 /* Parity Enable */
142
143/* SPCMDn - Command Registers */
144#define SPCMD_SCKDEN 0x8000 /* Clock Delay Setting Enable */
145#define SPCMD_SLNDEN 0x4000 /* SSL Negation Delay Setting Enable */
146#define SPCMD_SPNDEN 0x2000 /* Next-Access Delay Enable */
147#define SPCMD_LSBF 0x1000 /* LSB First */
148#define SPCMD_SPB_MASK 0x0f00 /* Data Length Setting */
149#define SPCMD_SPB_8_TO_16(bit) (((bit - 1) << 8) & SPCMD_SPB_MASK)
150#define SPCMD_SPB_8BIT 0x0000 /* QSPI only */
151#define SPCMD_SPB_16BIT 0x0100
152#define SPCMD_SPB_20BIT 0x0000
153#define SPCMD_SPB_24BIT 0x0100
154#define SPCMD_SPB_32BIT 0x0200
155#define SPCMD_SSLKP 0x0080 /* SSL Signal Level Keeping */
156#define SPCMD_SPIMOD_MASK 0x0060 /* SPI Operating Mode (QSPI only) */
157#define SPCMD_SPIMOD1 0x0040
158#define SPCMD_SPIMOD0 0x0020
159#define SPCMD_SPIMOD_SINGLE 0
160#define SPCMD_SPIMOD_DUAL SPCMD_SPIMOD0
161#define SPCMD_SPIMOD_QUAD SPCMD_SPIMOD1
162#define SPCMD_SPRW 0x0010 /* SPI Read/Write Access (Dual/Quad) */
163#define SPCMD_SSLA(i) ((i) << 4) /* SSL Assert Signal Setting */
164#define SPCMD_BRDV_MASK 0x000c /* Bit Rate Division Setting */
165#define SPCMD_BRDV(brdv) ((brdv) << 2)
166#define SPCMD_CPOL 0x0002 /* Clock Polarity Setting */
167#define SPCMD_CPHA 0x0001 /* Clock Phase Setting */
168
169/* SPBFCR - Buffer Control Register */
170#define SPBFCR_TXRST 0x80 /* Transmit Buffer Data Reset */
171#define SPBFCR_RXRST 0x40 /* Receive Buffer Data Reset */
172#define SPBFCR_TXTRG_MASK 0x30 /* Transmit Buffer Data Triggering Number */
173#define SPBFCR_RXTRG_MASK 0x07 /* Receive Buffer Data Triggering Number */
174/* QSPI on R-Car Gen2 */
175#define SPBFCR_TXTRG_1B 0x00 /* 31 bytes (1 byte available) */
176#define SPBFCR_TXTRG_32B 0x30 /* 0 byte (32 bytes available) */
177#define SPBFCR_RXTRG_1B 0x00 /* 1 byte (31 bytes available) */
178#define SPBFCR_RXTRG_32B 0x07 /* 32 bytes (0 byte available) */
179
180#define QSPI_BUFFER_SIZE 32u
181
182struct rspi_data {
183 void __iomem *addr;
184 u32 speed_hz;
185 struct spi_controller *ctlr;
186 struct platform_device *pdev;
187 wait_queue_head_t wait;
188 spinlock_t lock; /* Protects RMW-access to RSPI_SSLP */
189 struct clk *clk;
190 u16 spcmd;
191 u8 spsr;
192 u8 sppcr;
193 int rx_irq, tx_irq;
194 const struct spi_ops *ops;
195
196 unsigned dma_callbacked:1;
197 unsigned byte_access:1;
198};
199
200static void rspi_write8(const struct rspi_data *rspi, u8 data, u16 offset)
201{
202 iowrite8(data, rspi->addr + offset);
203}
204
205static void rspi_write16(const struct rspi_data *rspi, u16 data, u16 offset)
206{
207 iowrite16(data, rspi->addr + offset);
208}
209
210static void rspi_write32(const struct rspi_data *rspi, u32 data, u16 offset)
211{
212 iowrite32(data, rspi->addr + offset);
213}
214
215static u8 rspi_read8(const struct rspi_data *rspi, u16 offset)
216{
217 return ioread8(rspi->addr + offset);
218}
219
220static u16 rspi_read16(const struct rspi_data *rspi, u16 offset)
221{
222 return ioread16(rspi->addr + offset);
223}
224
225static void rspi_write_data(const struct rspi_data *rspi, u16 data)
226{
227 if (rspi->byte_access)
228 rspi_write8(rspi, data, RSPI_SPDR);
229 else /* 16 bit */
230 rspi_write16(rspi, data, RSPI_SPDR);
231}
232
233static u16 rspi_read_data(const struct rspi_data *rspi)
234{
235 if (rspi->byte_access)
236 return rspi_read8(rspi, RSPI_SPDR);
237 else /* 16 bit */
238 return rspi_read16(rspi, RSPI_SPDR);
239}
240
241/* optional functions */
242struct spi_ops {
243 int (*set_config_register)(struct rspi_data *rspi, int access_size);
244 int (*transfer_one)(struct spi_controller *ctlr,
245 struct spi_device *spi, struct spi_transfer *xfer);
246 u16 extra_mode_bits;
247 u16 min_div;
248 u16 max_div;
249 u16 flags;
250 u16 fifo_size;
251 u8 num_hw_ss;
252};
253
254static void rspi_set_rate(struct rspi_data *rspi)
255{
256 unsigned long clksrc;
257 int brdv = 0, spbr;
258
259 clksrc = clk_get_rate(rspi->clk);
260 spbr = DIV_ROUND_UP(clksrc, 2 * rspi->speed_hz) - 1;
261 while (spbr > 255 && brdv < 3) {
262 brdv++;
263 spbr = DIV_ROUND_UP(spbr + 1, 2) - 1;
264 }
265
266 rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR);
267 rspi->spcmd |= SPCMD_BRDV(brdv);
268 rspi->speed_hz = DIV_ROUND_UP(clksrc, (2U << brdv) * (spbr + 1));
269}
270
271/*
272 * functions for RSPI on legacy SH
273 */
274static int rspi_set_config_register(struct rspi_data *rspi, int access_size)
275{
276 /* Sets output mode, MOSI signal, and (optionally) loopback */
277 rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
278
279 /* Sets transfer bit rate */
280 rspi_set_rate(rspi);
281
282 /* Disable dummy transmission, set 16-bit word access, 1 frame */
283 rspi_write8(rspi, 0, RSPI_SPDCR);
284 rspi->byte_access = 0;
285
286 /* Sets RSPCK, SSL, next-access delay value */
287 rspi_write8(rspi, 0x00, RSPI_SPCKD);
288 rspi_write8(rspi, 0x00, RSPI_SSLND);
289 rspi_write8(rspi, 0x00, RSPI_SPND);
290
291 /* Sets parity, interrupt mask */
292 rspi_write8(rspi, 0x00, RSPI_SPCR2);
293
294 /* Resets sequencer */
295 rspi_write8(rspi, 0, RSPI_SPSCR);
296 rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
297 rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
298
299 /* Sets RSPI mode */
300 rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
301
302 return 0;
303}
304
305/*
306 * functions for RSPI on RZ
307 */
308static int rspi_rz_set_config_register(struct rspi_data *rspi, int access_size)
309{
310 /* Sets output mode, MOSI signal, and (optionally) loopback */
311 rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
312
313 /* Sets transfer bit rate */
314 rspi_set_rate(rspi);
315
316 /* Disable dummy transmission, set byte access */
317 rspi_write8(rspi, SPDCR_SPLBYTE, RSPI_SPDCR);
318 rspi->byte_access = 1;
319
320 /* Sets RSPCK, SSL, next-access delay value */
321 rspi_write8(rspi, 0x00, RSPI_SPCKD);
322 rspi_write8(rspi, 0x00, RSPI_SSLND);
323 rspi_write8(rspi, 0x00, RSPI_SPND);
324
325 /* Resets sequencer */
326 rspi_write8(rspi, 0, RSPI_SPSCR);
327 rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size);
328 rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
329
330 /* Sets RSPI mode */
331 rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
332
333 return 0;
334}
335
336/*
337 * functions for QSPI
338 */
339static int qspi_set_config_register(struct rspi_data *rspi, int access_size)
340{
341 unsigned long clksrc;
342 int brdv = 0, spbr;
343
344 /* Sets output mode, MOSI signal, and (optionally) loopback */
345 rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR);
346
347 /* Sets transfer bit rate */
348 clksrc = clk_get_rate(rspi->clk);
349 if (rspi->speed_hz >= clksrc) {
350 spbr = 0;
351 rspi->speed_hz = clksrc;
352 } else {
353 spbr = DIV_ROUND_UP(clksrc, 2 * rspi->speed_hz);
354 while (spbr > 255 && brdv < 3) {
355 brdv++;
356 spbr = DIV_ROUND_UP(spbr, 2);
357 }
358 spbr = clamp(spbr, 0, 255);
359 rspi->speed_hz = DIV_ROUND_UP(clksrc, (2U << brdv) * spbr);
360 }
361 rspi_write8(rspi, spbr, RSPI_SPBR);
362 rspi->spcmd |= SPCMD_BRDV(brdv);
363
364 /* Disable dummy transmission, set byte access */
365 rspi_write8(rspi, 0, RSPI_SPDCR);
366 rspi->byte_access = 1;
367
368 /* Sets RSPCK, SSL, next-access delay value */
369 rspi_write8(rspi, 0x00, RSPI_SPCKD);
370 rspi_write8(rspi, 0x00, RSPI_SSLND);
371 rspi_write8(rspi, 0x00, RSPI_SPND);
372
373 /* Data Length Setting */
374 if (access_size == 8)
375 rspi->spcmd |= SPCMD_SPB_8BIT;
376 else if (access_size == 16)
377 rspi->spcmd |= SPCMD_SPB_16BIT;
378 else
379 rspi->spcmd |= SPCMD_SPB_32BIT;
380
381 rspi->spcmd |= SPCMD_SCKDEN | SPCMD_SLNDEN | SPCMD_SPNDEN;
382
383 /* Resets transfer data length */
384 rspi_write32(rspi, 0, QSPI_SPBMUL0);
385
386 /* Resets transmit and receive buffer */
387 rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
388 /* Sets buffer to allow normal operation */
389 rspi_write8(rspi, 0x00, QSPI_SPBFCR);
390
391 /* Resets sequencer */
392 rspi_write8(rspi, 0, RSPI_SPSCR);
393 rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
394
395 /* Sets RSPI mode */
396 rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
397
398 return 0;
399}
400
401static void qspi_update(const struct rspi_data *rspi, u8 mask, u8 val, u8 reg)
402{
403 u8 data;
404
405 data = rspi_read8(rspi, reg);
406 data &= ~mask;
407 data |= (val & mask);
408 rspi_write8(rspi, data, reg);
409}
410
411static unsigned int qspi_set_send_trigger(struct rspi_data *rspi,
412 unsigned int len)
413{
414 unsigned int n;
415
416 n = min(len, QSPI_BUFFER_SIZE);
417
418 if (len >= QSPI_BUFFER_SIZE) {
419 /* sets triggering number to 32 bytes */
420 qspi_update(rspi, SPBFCR_TXTRG_MASK,
421 SPBFCR_TXTRG_32B, QSPI_SPBFCR);
422 } else {
423 /* sets triggering number to 1 byte */
424 qspi_update(rspi, SPBFCR_TXTRG_MASK,
425 SPBFCR_TXTRG_1B, QSPI_SPBFCR);
426 }
427
428 return n;
429}
430
431static int qspi_set_receive_trigger(struct rspi_data *rspi, unsigned int len)
432{
433 unsigned int n;
434
435 n = min(len, QSPI_BUFFER_SIZE);
436
437 if (len >= QSPI_BUFFER_SIZE) {
438 /* sets triggering number to 32 bytes */
439 qspi_update(rspi, SPBFCR_RXTRG_MASK,
440 SPBFCR_RXTRG_32B, QSPI_SPBFCR);
441 } else {
442 /* sets triggering number to 1 byte */
443 qspi_update(rspi, SPBFCR_RXTRG_MASK,
444 SPBFCR_RXTRG_1B, QSPI_SPBFCR);
445 }
446 return n;
447}
448
449static void rspi_enable_irq(const struct rspi_data *rspi, u8 enable)
450{
451 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | enable, RSPI_SPCR);
452}
453
454static void rspi_disable_irq(const struct rspi_data *rspi, u8 disable)
455{
456 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~disable, RSPI_SPCR);
457}
458
459static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask,
460 u8 enable_bit)
461{
462 int ret;
463
464 rspi->spsr = rspi_read8(rspi, RSPI_SPSR);
465 if (rspi->spsr & wait_mask)
466 return 0;
467
468 rspi_enable_irq(rspi, enable_bit);
469 ret = wait_event_timeout(rspi->wait, rspi->spsr & wait_mask, HZ);
470 if (ret == 0 && !(rspi->spsr & wait_mask))
471 return -ETIMEDOUT;
472
473 return 0;
474}
475
476static inline int rspi_wait_for_tx_empty(struct rspi_data *rspi)
477{
478 return rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
479}
480
481static inline int rspi_wait_for_rx_full(struct rspi_data *rspi)
482{
483 return rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE);
484}
485
486static int rspi_data_out(struct rspi_data *rspi, u8 data)
487{
488 int error = rspi_wait_for_tx_empty(rspi);
489 if (error < 0) {
490 dev_err(&rspi->ctlr->dev, "transmit timeout\n");
491 return error;
492 }
493 rspi_write_data(rspi, data);
494 return 0;
495}
496
497static int rspi_data_in(struct rspi_data *rspi)
498{
499 int error;
500 u8 data;
501
502 error = rspi_wait_for_rx_full(rspi);
503 if (error < 0) {
504 dev_err(&rspi->ctlr->dev, "receive timeout\n");
505 return error;
506 }
507 data = rspi_read_data(rspi);
508 return data;
509}
510
511static int rspi_pio_transfer(struct rspi_data *rspi, const u8 *tx, u8 *rx,
512 unsigned int n)
513{
514 while (n-- > 0) {
515 if (tx) {
516 int ret = rspi_data_out(rspi, *tx++);
517 if (ret < 0)
518 return ret;
519 }
520 if (rx) {
521 int ret = rspi_data_in(rspi);
522 if (ret < 0)
523 return ret;
524 *rx++ = ret;
525 }
526 }
527
528 return 0;
529}
530
531static void rspi_dma_complete(void *arg)
532{
533 struct rspi_data *rspi = arg;
534
535 rspi->dma_callbacked = 1;
536 wake_up_interruptible(&rspi->wait);
537}
538
539static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
540 struct sg_table *rx)
541{
542 struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL;
543 u8 irq_mask = 0;
544 unsigned int other_irq = 0;
545 dma_cookie_t cookie;
546 int ret;
547
548 /* First prepare and submit the DMA request(s), as this may fail */
549 if (rx) {
550 desc_rx = dmaengine_prep_slave_sg(rspi->ctlr->dma_rx, rx->sgl,
551 rx->nents, DMA_DEV_TO_MEM,
552 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
553 if (!desc_rx) {
554 ret = -EAGAIN;
555 goto no_dma_rx;
556 }
557
558 desc_rx->callback = rspi_dma_complete;
559 desc_rx->callback_param = rspi;
560 cookie = dmaengine_submit(desc_rx);
561 if (dma_submit_error(cookie)) {
562 ret = cookie;
563 goto no_dma_rx;
564 }
565
566 irq_mask |= SPCR_SPRIE;
567 }
568
569 if (tx) {
570 desc_tx = dmaengine_prep_slave_sg(rspi->ctlr->dma_tx, tx->sgl,
571 tx->nents, DMA_MEM_TO_DEV,
572 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
573 if (!desc_tx) {
574 ret = -EAGAIN;
575 goto no_dma_tx;
576 }
577
578 if (rx) {
579 /* No callback */
580 desc_tx->callback = NULL;
581 } else {
582 desc_tx->callback = rspi_dma_complete;
583 desc_tx->callback_param = rspi;
584 }
585 cookie = dmaengine_submit(desc_tx);
586 if (dma_submit_error(cookie)) {
587 ret = cookie;
588 goto no_dma_tx;
589 }
590
591 irq_mask |= SPCR_SPTIE;
592 }
593
594 /*
595 * DMAC needs SPxIE, but if SPxIE is set, the IRQ routine will be
596 * called. So, this driver disables the IRQ while DMA transfer.
597 */
598 if (tx)
599 disable_irq(other_irq = rspi->tx_irq);
600 if (rx && rspi->rx_irq != other_irq)
601 disable_irq(rspi->rx_irq);
602
603 rspi_enable_irq(rspi, irq_mask);
604 rspi->dma_callbacked = 0;
605
606 /* Now start DMA */
607 if (rx)
608 dma_async_issue_pending(rspi->ctlr->dma_rx);
609 if (tx)
610 dma_async_issue_pending(rspi->ctlr->dma_tx);
611
612 ret = wait_event_interruptible_timeout(rspi->wait,
613 rspi->dma_callbacked, HZ);
614 if (ret > 0 && rspi->dma_callbacked) {
615 ret = 0;
616 if (tx)
617 dmaengine_synchronize(rspi->ctlr->dma_tx);
618 if (rx)
619 dmaengine_synchronize(rspi->ctlr->dma_rx);
620 } else {
621 if (!ret) {
622 dev_err(&rspi->ctlr->dev, "DMA timeout\n");
623 ret = -ETIMEDOUT;
624 }
625 if (tx)
626 dmaengine_terminate_sync(rspi->ctlr->dma_tx);
627 if (rx)
628 dmaengine_terminate_sync(rspi->ctlr->dma_rx);
629 }
630
631 rspi_disable_irq(rspi, irq_mask);
632
633 if (tx)
634 enable_irq(rspi->tx_irq);
635 if (rx && rspi->rx_irq != other_irq)
636 enable_irq(rspi->rx_irq);
637
638 return ret;
639
640no_dma_tx:
641 if (rx)
642 dmaengine_terminate_sync(rspi->ctlr->dma_rx);
643no_dma_rx:
644 if (ret == -EAGAIN) {
645 dev_warn_once(&rspi->ctlr->dev,
646 "DMA not available, falling back to PIO\n");
647 }
648 return ret;
649}
650
651static void rspi_receive_init(const struct rspi_data *rspi)
652{
653 u8 spsr;
654
655 spsr = rspi_read8(rspi, RSPI_SPSR);
656 if (spsr & SPSR_SPRF)
657 rspi_read_data(rspi); /* dummy read */
658 if (spsr & SPSR_OVRF)
659 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF,
660 RSPI_SPSR);
661}
662
663static void rspi_rz_receive_init(const struct rspi_data *rspi)
664{
665 rspi_receive_init(rspi);
666 rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, RSPI_SPBFCR);
667 rspi_write8(rspi, 0, RSPI_SPBFCR);
668}
669
670static void qspi_receive_init(const struct rspi_data *rspi)
671{
672 u8 spsr;
673
674 spsr = rspi_read8(rspi, RSPI_SPSR);
675 if (spsr & SPSR_SPRF)
676 rspi_read_data(rspi); /* dummy read */
677 rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR);
678 rspi_write8(rspi, 0, QSPI_SPBFCR);
679}
680
681static bool __rspi_can_dma(const struct rspi_data *rspi,
682 const struct spi_transfer *xfer)
683{
684 return xfer->len > rspi->ops->fifo_size;
685}
686
687static bool rspi_can_dma(struct spi_controller *ctlr, struct spi_device *spi,
688 struct spi_transfer *xfer)
689{
690 struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
691
692 return __rspi_can_dma(rspi, xfer);
693}
694
695static int rspi_dma_check_then_transfer(struct rspi_data *rspi,
696 struct spi_transfer *xfer)
697{
698 if (!rspi->ctlr->can_dma || !__rspi_can_dma(rspi, xfer))
699 return -EAGAIN;
700
701 /* rx_buf can be NULL on RSPI on SH in TX-only Mode */
702 return rspi_dma_transfer(rspi, &xfer->tx_sg,
703 xfer->rx_buf ? &xfer->rx_sg : NULL);
704}
705
706static int rspi_common_transfer(struct rspi_data *rspi,
707 struct spi_transfer *xfer)
708{
709 int ret;
710
711 xfer->effective_speed_hz = rspi->speed_hz;
712
713 ret = rspi_dma_check_then_transfer(rspi, xfer);
714 if (ret != -EAGAIN)
715 return ret;
716
717 ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len);
718 if (ret < 0)
719 return ret;
720
721 /* Wait for the last transmission */
722 rspi_wait_for_tx_empty(rspi);
723
724 return 0;
725}
726
727static int rspi_transfer_one(struct spi_controller *ctlr,
728 struct spi_device *spi, struct spi_transfer *xfer)
729{
730 struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
731 u8 spcr;
732
733 spcr = rspi_read8(rspi, RSPI_SPCR);
734 if (xfer->rx_buf) {
735 rspi_receive_init(rspi);
736 spcr &= ~SPCR_TXMD;
737 } else {
738 spcr |= SPCR_TXMD;
739 }
740 rspi_write8(rspi, spcr, RSPI_SPCR);
741
742 return rspi_common_transfer(rspi, xfer);
743}
744
745static int rspi_rz_transfer_one(struct spi_controller *ctlr,
746 struct spi_device *spi,
747 struct spi_transfer *xfer)
748{
749 struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
750
751 rspi_rz_receive_init(rspi);
752
753 return rspi_common_transfer(rspi, xfer);
754}
755
756static int qspi_trigger_transfer_out_in(struct rspi_data *rspi, const u8 *tx,
757 u8 *rx, unsigned int len)
758{
759 unsigned int i, n;
760 int ret;
761
762 while (len > 0) {
763 n = qspi_set_send_trigger(rspi, len);
764 qspi_set_receive_trigger(rspi, len);
765 ret = rspi_wait_for_tx_empty(rspi);
766 if (ret < 0) {
767 dev_err(&rspi->ctlr->dev, "transmit timeout\n");
768 return ret;
769 }
770 for (i = 0; i < n; i++)
771 rspi_write_data(rspi, *tx++);
772
773 ret = rspi_wait_for_rx_full(rspi);
774 if (ret < 0) {
775 dev_err(&rspi->ctlr->dev, "receive timeout\n");
776 return ret;
777 }
778 for (i = 0; i < n; i++)
779 *rx++ = rspi_read_data(rspi);
780
781 len -= n;
782 }
783
784 return 0;
785}
786
787static int qspi_transfer_out_in(struct rspi_data *rspi,
788 struct spi_transfer *xfer)
789{
790 int ret;
791
792 qspi_receive_init(rspi);
793
794 ret = rspi_dma_check_then_transfer(rspi, xfer);
795 if (ret != -EAGAIN)
796 return ret;
797
798 return qspi_trigger_transfer_out_in(rspi, xfer->tx_buf,
799 xfer->rx_buf, xfer->len);
800}
801
802static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer)
803{
804 const u8 *tx = xfer->tx_buf;
805 unsigned int n = xfer->len;
806 unsigned int i, len;
807 int ret;
808
809 if (rspi->ctlr->can_dma && __rspi_can_dma(rspi, xfer)) {
810 ret = rspi_dma_transfer(rspi, &xfer->tx_sg, NULL);
811 if (ret != -EAGAIN)
812 return ret;
813 }
814
815 while (n > 0) {
816 len = qspi_set_send_trigger(rspi, n);
817 ret = rspi_wait_for_tx_empty(rspi);
818 if (ret < 0) {
819 dev_err(&rspi->ctlr->dev, "transmit timeout\n");
820 return ret;
821 }
822 for (i = 0; i < len; i++)
823 rspi_write_data(rspi, *tx++);
824
825 n -= len;
826 }
827
828 /* Wait for the last transmission */
829 rspi_wait_for_tx_empty(rspi);
830
831 return 0;
832}
833
834static int qspi_transfer_in(struct rspi_data *rspi, struct spi_transfer *xfer)
835{
836 u8 *rx = xfer->rx_buf;
837 unsigned int n = xfer->len;
838 unsigned int i, len;
839 int ret;
840
841 if (rspi->ctlr->can_dma && __rspi_can_dma(rspi, xfer)) {
842 ret = rspi_dma_transfer(rspi, NULL, &xfer->rx_sg);
843 if (ret != -EAGAIN)
844 return ret;
845 }
846
847 while (n > 0) {
848 len = qspi_set_receive_trigger(rspi, n);
849 ret = rspi_wait_for_rx_full(rspi);
850 if (ret < 0) {
851 dev_err(&rspi->ctlr->dev, "receive timeout\n");
852 return ret;
853 }
854 for (i = 0; i < len; i++)
855 *rx++ = rspi_read_data(rspi);
856
857 n -= len;
858 }
859
860 return 0;
861}
862
863static int qspi_transfer_one(struct spi_controller *ctlr,
864 struct spi_device *spi, struct spi_transfer *xfer)
865{
866 struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
867
868 xfer->effective_speed_hz = rspi->speed_hz;
869 if (spi->mode & SPI_LOOP) {
870 return qspi_transfer_out_in(rspi, xfer);
871 } else if (xfer->tx_nbits > SPI_NBITS_SINGLE) {
872 /* Quad or Dual SPI Write */
873 return qspi_transfer_out(rspi, xfer);
874 } else if (xfer->rx_nbits > SPI_NBITS_SINGLE) {
875 /* Quad or Dual SPI Read */
876 return qspi_transfer_in(rspi, xfer);
877 } else {
878 /* Single SPI Transfer */
879 return qspi_transfer_out_in(rspi, xfer);
880 }
881}
882
883static u16 qspi_transfer_mode(const struct spi_transfer *xfer)
884{
885 if (xfer->tx_buf)
886 switch (xfer->tx_nbits) {
887 case SPI_NBITS_QUAD:
888 return SPCMD_SPIMOD_QUAD;
889 case SPI_NBITS_DUAL:
890 return SPCMD_SPIMOD_DUAL;
891 default:
892 return 0;
893 }
894 if (xfer->rx_buf)
895 switch (xfer->rx_nbits) {
896 case SPI_NBITS_QUAD:
897 return SPCMD_SPIMOD_QUAD | SPCMD_SPRW;
898 case SPI_NBITS_DUAL:
899 return SPCMD_SPIMOD_DUAL | SPCMD_SPRW;
900 default:
901 return 0;
902 }
903
904 return 0;
905}
906
907static int qspi_setup_sequencer(struct rspi_data *rspi,
908 const struct spi_message *msg)
909{
910 const struct spi_transfer *xfer;
911 unsigned int i = 0, len = 0;
912 u16 current_mode = 0xffff, mode;
913
914 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
915 mode = qspi_transfer_mode(xfer);
916 if (mode == current_mode) {
917 len += xfer->len;
918 continue;
919 }
920
921 /* Transfer mode change */
922 if (i) {
923 /* Set transfer data length of previous transfer */
924 rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
925 }
926
927 if (i >= QSPI_NUM_SPCMD) {
928 dev_err(&msg->spi->dev,
929 "Too many different transfer modes");
930 return -EINVAL;
931 }
932
933 /* Program transfer mode for this transfer */
934 rspi_write16(rspi, rspi->spcmd | mode, RSPI_SPCMD(i));
935 current_mode = mode;
936 len = xfer->len;
937 i++;
938 }
939 if (i) {
940 /* Set final transfer data length and sequence length */
941 rspi_write32(rspi, len, QSPI_SPBMUL(i - 1));
942 rspi_write8(rspi, i - 1, RSPI_SPSCR);
943 }
944
945 return 0;
946}
947
948static int rspi_setup(struct spi_device *spi)
949{
950 struct rspi_data *rspi = spi_controller_get_devdata(spi->controller);
951 u8 sslp;
952
953 if (spi_get_csgpiod(spi, 0))
954 return 0;
955
956 pm_runtime_get_sync(&rspi->pdev->dev);
957 spin_lock_irq(&rspi->lock);
958
959 sslp = rspi_read8(rspi, RSPI_SSLP);
960 if (spi->mode & SPI_CS_HIGH)
961 sslp |= SSLP_SSLP(spi_get_chipselect(spi, 0));
962 else
963 sslp &= ~SSLP_SSLP(spi_get_chipselect(spi, 0));
964 rspi_write8(rspi, sslp, RSPI_SSLP);
965
966 spin_unlock_irq(&rspi->lock);
967 pm_runtime_put(&rspi->pdev->dev);
968 return 0;
969}
970
971static int rspi_prepare_message(struct spi_controller *ctlr,
972 struct spi_message *msg)
973{
974 struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
975 struct spi_device *spi = msg->spi;
976 const struct spi_transfer *xfer;
977 int ret;
978
979 /*
980 * As the Bit Rate Register must not be changed while the device is
981 * active, all transfers in a message must use the same bit rate.
982 * In theory, the sequencer could be enabled, and each Command Register
983 * could divide the base bit rate by a different value.
984 * However, most RSPI variants do not have Transfer Data Length
985 * Multiplier Setting Registers, so each sequence step would be limited
986 * to a single word, making this feature unsuitable for large
987 * transfers, which would gain most from it.
988 */
989 rspi->speed_hz = spi->max_speed_hz;
990 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
991 if (xfer->speed_hz < rspi->speed_hz)
992 rspi->speed_hz = xfer->speed_hz;
993 }
994
995 rspi->spcmd = SPCMD_SSLKP;
996 if (spi->mode & SPI_CPOL)
997 rspi->spcmd |= SPCMD_CPOL;
998 if (spi->mode & SPI_CPHA)
999 rspi->spcmd |= SPCMD_CPHA;
1000 if (spi->mode & SPI_LSB_FIRST)
1001 rspi->spcmd |= SPCMD_LSBF;
1002
1003 /* Configure slave signal to assert */
1004 rspi->spcmd |= SPCMD_SSLA(spi_get_csgpiod(spi, 0) ? rspi->ctlr->unused_native_cs
1005 : spi_get_chipselect(spi, 0));
1006
1007 /* CMOS output mode and MOSI signal from previous transfer */
1008 rspi->sppcr = 0;
1009 if (spi->mode & SPI_LOOP)
1010 rspi->sppcr |= SPPCR_SPLP;
1011
1012 rspi->ops->set_config_register(rspi, 8);
1013
1014 if (msg->spi->mode &
1015 (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD)) {
1016 /* Setup sequencer for messages with multiple transfer modes */
1017 ret = qspi_setup_sequencer(rspi, msg);
1018 if (ret < 0)
1019 return ret;
1020 }
1021
1022 /* Enable SPI function in master mode */
1023 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR);
1024 return 0;
1025}
1026
1027static int rspi_unprepare_message(struct spi_controller *ctlr,
1028 struct spi_message *msg)
1029{
1030 struct rspi_data *rspi = spi_controller_get_devdata(ctlr);
1031
1032 /* Disable SPI function */
1033 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR);
1034
1035 /* Reset sequencer for Single SPI Transfers */
1036 rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0);
1037 rspi_write8(rspi, 0, RSPI_SPSCR);
1038 return 0;
1039}
1040
1041static irqreturn_t rspi_irq_mux(int irq, void *_sr)
1042{
1043 struct rspi_data *rspi = _sr;
1044 u8 spsr;
1045 irqreturn_t ret = IRQ_NONE;
1046 u8 disable_irq = 0;
1047
1048 rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1049 if (spsr & SPSR_SPRF)
1050 disable_irq |= SPCR_SPRIE;
1051 if (spsr & SPSR_SPTEF)
1052 disable_irq |= SPCR_SPTIE;
1053
1054 if (disable_irq) {
1055 ret = IRQ_HANDLED;
1056 rspi_disable_irq(rspi, disable_irq);
1057 wake_up(&rspi->wait);
1058 }
1059
1060 return ret;
1061}
1062
1063static irqreturn_t rspi_irq_rx(int irq, void *_sr)
1064{
1065 struct rspi_data *rspi = _sr;
1066 u8 spsr;
1067
1068 rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1069 if (spsr & SPSR_SPRF) {
1070 rspi_disable_irq(rspi, SPCR_SPRIE);
1071 wake_up(&rspi->wait);
1072 return IRQ_HANDLED;
1073 }
1074
1075 return 0;
1076}
1077
1078static irqreturn_t rspi_irq_tx(int irq, void *_sr)
1079{
1080 struct rspi_data *rspi = _sr;
1081 u8 spsr;
1082
1083 rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
1084 if (spsr & SPSR_SPTEF) {
1085 rspi_disable_irq(rspi, SPCR_SPTIE);
1086 wake_up(&rspi->wait);
1087 return IRQ_HANDLED;
1088 }
1089
1090 return 0;
1091}
1092
1093static struct dma_chan *rspi_request_dma_chan(struct device *dev,
1094 enum dma_transfer_direction dir,
1095 unsigned int id,
1096 dma_addr_t port_addr)
1097{
1098 dma_cap_mask_t mask;
1099 struct dma_chan *chan;
1100 struct dma_slave_config cfg;
1101 int ret;
1102
1103 dma_cap_zero(mask);
1104 dma_cap_set(DMA_SLAVE, mask);
1105
1106 chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
1107 (void *)(unsigned long)id, dev,
1108 dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1109 if (!chan) {
1110 dev_warn(dev, "dma_request_slave_channel_compat failed\n");
1111 return NULL;
1112 }
1113
1114 memset(&cfg, 0, sizeof(cfg));
1115 cfg.dst_addr = port_addr + RSPI_SPDR;
1116 cfg.src_addr = port_addr + RSPI_SPDR;
1117 cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1118 cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1119 cfg.direction = dir;
1120
1121 ret = dmaengine_slave_config(chan, &cfg);
1122 if (ret) {
1123 dev_warn(dev, "dmaengine_slave_config failed %d\n", ret);
1124 dma_release_channel(chan);
1125 return NULL;
1126 }
1127
1128 return chan;
1129}
1130
1131static int rspi_request_dma(struct device *dev, struct spi_controller *ctlr,
1132 const struct resource *res)
1133{
1134 const struct rspi_plat_data *rspi_pd = dev_get_platdata(dev);
1135 unsigned int dma_tx_id, dma_rx_id;
1136
1137 if (dev->of_node) {
1138 /* In the OF case we will get the slave IDs from the DT */
1139 dma_tx_id = 0;
1140 dma_rx_id = 0;
1141 } else if (rspi_pd && rspi_pd->dma_tx_id && rspi_pd->dma_rx_id) {
1142 dma_tx_id = rspi_pd->dma_tx_id;
1143 dma_rx_id = rspi_pd->dma_rx_id;
1144 } else {
1145 /* The driver assumes no error. */
1146 return 0;
1147 }
1148
1149 ctlr->dma_tx = rspi_request_dma_chan(dev, DMA_MEM_TO_DEV, dma_tx_id,
1150 res->start);
1151 if (!ctlr->dma_tx)
1152 return -ENODEV;
1153
1154 ctlr->dma_rx = rspi_request_dma_chan(dev, DMA_DEV_TO_MEM, dma_rx_id,
1155 res->start);
1156 if (!ctlr->dma_rx) {
1157 dma_release_channel(ctlr->dma_tx);
1158 ctlr->dma_tx = NULL;
1159 return -ENODEV;
1160 }
1161
1162 ctlr->can_dma = rspi_can_dma;
1163 dev_info(dev, "DMA available");
1164 return 0;
1165}
1166
1167static void rspi_release_dma(struct spi_controller *ctlr)
1168{
1169 if (ctlr->dma_tx)
1170 dma_release_channel(ctlr->dma_tx);
1171 if (ctlr->dma_rx)
1172 dma_release_channel(ctlr->dma_rx);
1173}
1174
1175static void rspi_remove(struct platform_device *pdev)
1176{
1177 struct rspi_data *rspi = platform_get_drvdata(pdev);
1178
1179 rspi_release_dma(rspi->ctlr);
1180 pm_runtime_disable(&pdev->dev);
1181}
1182
1183static const struct spi_ops rspi_ops = {
1184 .set_config_register = rspi_set_config_register,
1185 .transfer_one = rspi_transfer_one,
1186 .min_div = 2,
1187 .max_div = 4096,
1188 .flags = SPI_CONTROLLER_MUST_TX,
1189 .fifo_size = 8,
1190 .num_hw_ss = 2,
1191};
1192
1193static const struct spi_ops rspi_rz_ops __maybe_unused = {
1194 .set_config_register = rspi_rz_set_config_register,
1195 .transfer_one = rspi_rz_transfer_one,
1196 .min_div = 2,
1197 .max_div = 4096,
1198 .flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX,
1199 .fifo_size = 8, /* 8 for TX, 32 for RX */
1200 .num_hw_ss = 1,
1201};
1202
1203static const struct spi_ops qspi_ops __maybe_unused = {
1204 .set_config_register = qspi_set_config_register,
1205 .transfer_one = qspi_transfer_one,
1206 .extra_mode_bits = SPI_TX_DUAL | SPI_TX_QUAD |
1207 SPI_RX_DUAL | SPI_RX_QUAD,
1208 .min_div = 1,
1209 .max_div = 4080,
1210 .flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX,
1211 .fifo_size = 32,
1212 .num_hw_ss = 1,
1213};
1214
1215static const struct of_device_id rspi_of_match[] __maybe_unused = {
1216 /* RSPI on legacy SH */
1217 { .compatible = "renesas,rspi", .data = &rspi_ops },
1218 /* RSPI on RZ/A1H */
1219 { .compatible = "renesas,rspi-rz", .data = &rspi_rz_ops },
1220 /* QSPI on R-Car Gen2 */
1221 { .compatible = "renesas,qspi", .data = &qspi_ops },
1222 { /* sentinel */ }
1223};
1224
1225MODULE_DEVICE_TABLE(of, rspi_of_match);
1226
1227#ifdef CONFIG_OF
1228static void rspi_reset_control_assert(void *data)
1229{
1230 reset_control_assert(data);
1231}
1232
1233static int rspi_parse_dt(struct device *dev, struct spi_controller *ctlr)
1234{
1235 struct reset_control *rstc;
1236 u32 num_cs;
1237 int error;
1238
1239 /* Parse DT properties */
1240 error = of_property_read_u32(dev->of_node, "num-cs", &num_cs);
1241 if (error) {
1242 dev_err(dev, "of_property_read_u32 num-cs failed %d\n", error);
1243 return error;
1244 }
1245
1246 ctlr->num_chipselect = num_cs;
1247
1248 rstc = devm_reset_control_get_optional_exclusive(dev, NULL);
1249 if (IS_ERR(rstc))
1250 return dev_err_probe(dev, PTR_ERR(rstc),
1251 "failed to get reset ctrl\n");
1252
1253 error = reset_control_deassert(rstc);
1254 if (error) {
1255 dev_err(dev, "failed to deassert reset %d\n", error);
1256 return error;
1257 }
1258
1259 error = devm_add_action_or_reset(dev, rspi_reset_control_assert, rstc);
1260 if (error) {
1261 dev_err(dev, "failed to register assert devm action, %d\n", error);
1262 return error;
1263 }
1264
1265 return 0;
1266}
1267#else
1268#define rspi_of_match NULL
1269static inline int rspi_parse_dt(struct device *dev, struct spi_controller *ctlr)
1270{
1271 return -EINVAL;
1272}
1273#endif /* CONFIG_OF */
1274
1275static int rspi_request_irq(struct device *dev, unsigned int irq,
1276 irq_handler_t handler, const char *suffix,
1277 void *dev_id)
1278{
1279 const char *name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s",
1280 dev_name(dev), suffix);
1281 if (!name)
1282 return -ENOMEM;
1283
1284 return devm_request_irq(dev, irq, handler, 0, name, dev_id);
1285}
1286
1287static int rspi_probe(struct platform_device *pdev)
1288{
1289 struct resource *res;
1290 struct spi_controller *ctlr;
1291 struct rspi_data *rspi;
1292 int ret;
1293 const struct rspi_plat_data *rspi_pd;
1294 const struct spi_ops *ops;
1295 unsigned long clksrc;
1296
1297 ctlr = spi_alloc_host(&pdev->dev, sizeof(struct rspi_data));
1298 if (ctlr == NULL)
1299 return -ENOMEM;
1300
1301 ops = of_device_get_match_data(&pdev->dev);
1302 if (ops) {
1303 ret = rspi_parse_dt(&pdev->dev, ctlr);
1304 if (ret)
1305 goto error1;
1306 } else {
1307 ops = (struct spi_ops *)pdev->id_entry->driver_data;
1308 rspi_pd = dev_get_platdata(&pdev->dev);
1309 if (rspi_pd && rspi_pd->num_chipselect)
1310 ctlr->num_chipselect = rspi_pd->num_chipselect;
1311 else
1312 ctlr->num_chipselect = 2; /* default */
1313 }
1314
1315 rspi = spi_controller_get_devdata(ctlr);
1316 platform_set_drvdata(pdev, rspi);
1317 rspi->ops = ops;
1318 rspi->ctlr = ctlr;
1319
1320 rspi->addr = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1321 if (IS_ERR(rspi->addr)) {
1322 ret = PTR_ERR(rspi->addr);
1323 goto error1;
1324 }
1325
1326 rspi->clk = devm_clk_get(&pdev->dev, NULL);
1327 if (IS_ERR(rspi->clk)) {
1328 dev_err(&pdev->dev, "cannot get clock\n");
1329 ret = PTR_ERR(rspi->clk);
1330 goto error1;
1331 }
1332
1333 rspi->pdev = pdev;
1334 pm_runtime_enable(&pdev->dev);
1335
1336 init_waitqueue_head(&rspi->wait);
1337 spin_lock_init(&rspi->lock);
1338
1339 ctlr->bus_num = pdev->id;
1340 ctlr->setup = rspi_setup;
1341 ctlr->auto_runtime_pm = true;
1342 ctlr->transfer_one = ops->transfer_one;
1343 ctlr->prepare_message = rspi_prepare_message;
1344 ctlr->unprepare_message = rspi_unprepare_message;
1345 ctlr->mode_bits = SPI_CPHA | SPI_CPOL | SPI_CS_HIGH | SPI_LSB_FIRST |
1346 SPI_LOOP | ops->extra_mode_bits;
1347 clksrc = clk_get_rate(rspi->clk);
1348 ctlr->min_speed_hz = DIV_ROUND_UP(clksrc, ops->max_div);
1349 ctlr->max_speed_hz = DIV_ROUND_UP(clksrc, ops->min_div);
1350 ctlr->flags = ops->flags;
1351 ctlr->dev.of_node = pdev->dev.of_node;
1352 ctlr->use_gpio_descriptors = true;
1353 ctlr->max_native_cs = rspi->ops->num_hw_ss;
1354
1355 ret = platform_get_irq_byname_optional(pdev, "rx");
1356 if (ret < 0) {
1357 ret = platform_get_irq_byname_optional(pdev, "mux");
1358 if (ret < 0)
1359 ret = platform_get_irq(pdev, 0);
1360 if (ret >= 0)
1361 rspi->rx_irq = rspi->tx_irq = ret;
1362 } else {
1363 rspi->rx_irq = ret;
1364 ret = platform_get_irq_byname(pdev, "tx");
1365 if (ret >= 0)
1366 rspi->tx_irq = ret;
1367 }
1368
1369 if (rspi->rx_irq == rspi->tx_irq) {
1370 /* Single multiplexed interrupt */
1371 ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_mux,
1372 "mux", rspi);
1373 } else {
1374 /* Multi-interrupt mode, only SPRI and SPTI are used */
1375 ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_rx,
1376 "rx", rspi);
1377 if (!ret)
1378 ret = rspi_request_irq(&pdev->dev, rspi->tx_irq,
1379 rspi_irq_tx, "tx", rspi);
1380 }
1381 if (ret < 0) {
1382 dev_err(&pdev->dev, "request_irq error\n");
1383 goto error2;
1384 }
1385
1386 ret = rspi_request_dma(&pdev->dev, ctlr, res);
1387 if (ret < 0)
1388 dev_warn(&pdev->dev, "DMA not available, using PIO\n");
1389
1390 ret = devm_spi_register_controller(&pdev->dev, ctlr);
1391 if (ret < 0) {
1392 dev_err(&pdev->dev, "devm_spi_register_controller error.\n");
1393 goto error3;
1394 }
1395
1396 dev_info(&pdev->dev, "probed\n");
1397
1398 return 0;
1399
1400error3:
1401 rspi_release_dma(ctlr);
1402error2:
1403 pm_runtime_disable(&pdev->dev);
1404error1:
1405 spi_controller_put(ctlr);
1406
1407 return ret;
1408}
1409
1410static const struct platform_device_id spi_driver_ids[] = {
1411 { "rspi", (kernel_ulong_t)&rspi_ops },
1412 {},
1413};
1414
1415MODULE_DEVICE_TABLE(platform, spi_driver_ids);
1416
1417#ifdef CONFIG_PM_SLEEP
1418static int rspi_suspend(struct device *dev)
1419{
1420 struct rspi_data *rspi = dev_get_drvdata(dev);
1421
1422 return spi_controller_suspend(rspi->ctlr);
1423}
1424
1425static int rspi_resume(struct device *dev)
1426{
1427 struct rspi_data *rspi = dev_get_drvdata(dev);
1428
1429 return spi_controller_resume(rspi->ctlr);
1430}
1431
1432static SIMPLE_DEV_PM_OPS(rspi_pm_ops, rspi_suspend, rspi_resume);
1433#define DEV_PM_OPS &rspi_pm_ops
1434#else
1435#define DEV_PM_OPS NULL
1436#endif /* CONFIG_PM_SLEEP */
1437
1438static struct platform_driver rspi_driver = {
1439 .probe = rspi_probe,
1440 .remove_new = rspi_remove,
1441 .id_table = spi_driver_ids,
1442 .driver = {
1443 .name = "renesas_spi",
1444 .pm = DEV_PM_OPS,
1445 .of_match_table = of_match_ptr(rspi_of_match),
1446 },
1447};
1448module_platform_driver(rspi_driver);
1449
1450MODULE_DESCRIPTION("Renesas RSPI bus driver");
1451MODULE_LICENSE("GPL v2");
1452MODULE_AUTHOR("Yoshihiro Shimoda");
1/*
2 * SH RSPI driver
3 *
4 * Copyright (C) 2012 Renesas Solutions Corp.
5 *
6 * Based on spi-sh.c:
7 * Copyright (C) 2011 Renesas Solutions Corp.
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; version 2 of the License.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
21 *
22 */
23
24#include <linux/module.h>
25#include <linux/kernel.h>
26#include <linux/sched.h>
27#include <linux/errno.h>
28#include <linux/list.h>
29#include <linux/workqueue.h>
30#include <linux/interrupt.h>
31#include <linux/platform_device.h>
32#include <linux/io.h>
33#include <linux/clk.h>
34#include <linux/dmaengine.h>
35#include <linux/dma-mapping.h>
36#include <linux/sh_dma.h>
37#include <linux/spi/spi.h>
38#include <linux/spi/rspi.h>
39
40#define RSPI_SPCR 0x00
41#define RSPI_SSLP 0x01
42#define RSPI_SPPCR 0x02
43#define RSPI_SPSR 0x03
44#define RSPI_SPDR 0x04
45#define RSPI_SPSCR 0x08
46#define RSPI_SPSSR 0x09
47#define RSPI_SPBR 0x0a
48#define RSPI_SPDCR 0x0b
49#define RSPI_SPCKD 0x0c
50#define RSPI_SSLND 0x0d
51#define RSPI_SPND 0x0e
52#define RSPI_SPCR2 0x0f
53#define RSPI_SPCMD0 0x10
54#define RSPI_SPCMD1 0x12
55#define RSPI_SPCMD2 0x14
56#define RSPI_SPCMD3 0x16
57#define RSPI_SPCMD4 0x18
58#define RSPI_SPCMD5 0x1a
59#define RSPI_SPCMD6 0x1c
60#define RSPI_SPCMD7 0x1e
61
62/* SPCR */
63#define SPCR_SPRIE 0x80
64#define SPCR_SPE 0x40
65#define SPCR_SPTIE 0x20
66#define SPCR_SPEIE 0x10
67#define SPCR_MSTR 0x08
68#define SPCR_MODFEN 0x04
69#define SPCR_TXMD 0x02
70#define SPCR_SPMS 0x01
71
72/* SSLP */
73#define SSLP_SSL1P 0x02
74#define SSLP_SSL0P 0x01
75
76/* SPPCR */
77#define SPPCR_MOIFE 0x20
78#define SPPCR_MOIFV 0x10
79#define SPPCR_SPOM 0x04
80#define SPPCR_SPLP2 0x02
81#define SPPCR_SPLP 0x01
82
83/* SPSR */
84#define SPSR_SPRF 0x80
85#define SPSR_SPTEF 0x20
86#define SPSR_PERF 0x08
87#define SPSR_MODF 0x04
88#define SPSR_IDLNF 0x02
89#define SPSR_OVRF 0x01
90
91/* SPSCR */
92#define SPSCR_SPSLN_MASK 0x07
93
94/* SPSSR */
95#define SPSSR_SPECM_MASK 0x70
96#define SPSSR_SPCP_MASK 0x07
97
98/* SPDCR */
99#define SPDCR_SPLW 0x20
100#define SPDCR_SPRDTD 0x10
101#define SPDCR_SLSEL1 0x08
102#define SPDCR_SLSEL0 0x04
103#define SPDCR_SLSEL_MASK 0x0c
104#define SPDCR_SPFC1 0x02
105#define SPDCR_SPFC0 0x01
106
107/* SPCKD */
108#define SPCKD_SCKDL_MASK 0x07
109
110/* SSLND */
111#define SSLND_SLNDL_MASK 0x07
112
113/* SPND */
114#define SPND_SPNDL_MASK 0x07
115
116/* SPCR2 */
117#define SPCR2_PTE 0x08
118#define SPCR2_SPIE 0x04
119#define SPCR2_SPOE 0x02
120#define SPCR2_SPPE 0x01
121
122/* SPCMDn */
123#define SPCMD_SCKDEN 0x8000
124#define SPCMD_SLNDEN 0x4000
125#define SPCMD_SPNDEN 0x2000
126#define SPCMD_LSBF 0x1000
127#define SPCMD_SPB_MASK 0x0f00
128#define SPCMD_SPB_8_TO_16(bit) (((bit - 1) << 8) & SPCMD_SPB_MASK)
129#define SPCMD_SPB_20BIT 0x0000
130#define SPCMD_SPB_24BIT 0x0100
131#define SPCMD_SPB_32BIT 0x0200
132#define SPCMD_SSLKP 0x0080
133#define SPCMD_SSLA_MASK 0x0030
134#define SPCMD_BRDV_MASK 0x000c
135#define SPCMD_CPOL 0x0002
136#define SPCMD_CPHA 0x0001
137
138struct rspi_data {
139 void __iomem *addr;
140 u32 max_speed_hz;
141 struct spi_master *master;
142 struct list_head queue;
143 struct work_struct ws;
144 wait_queue_head_t wait;
145 spinlock_t lock;
146 struct clk *clk;
147 unsigned char spsr;
148
149 /* for dmaengine */
150 struct sh_dmae_slave dma_tx;
151 struct sh_dmae_slave dma_rx;
152 struct dma_chan *chan_tx;
153 struct dma_chan *chan_rx;
154 int irq;
155
156 unsigned dma_width_16bit:1;
157 unsigned dma_callbacked:1;
158};
159
160static void rspi_write8(struct rspi_data *rspi, u8 data, u16 offset)
161{
162 iowrite8(data, rspi->addr + offset);
163}
164
165static void rspi_write16(struct rspi_data *rspi, u16 data, u16 offset)
166{
167 iowrite16(data, rspi->addr + offset);
168}
169
170static u8 rspi_read8(struct rspi_data *rspi, u16 offset)
171{
172 return ioread8(rspi->addr + offset);
173}
174
175static u16 rspi_read16(struct rspi_data *rspi, u16 offset)
176{
177 return ioread16(rspi->addr + offset);
178}
179
180static unsigned char rspi_calc_spbr(struct rspi_data *rspi)
181{
182 int tmp;
183 unsigned char spbr;
184
185 tmp = clk_get_rate(rspi->clk) / (2 * rspi->max_speed_hz) - 1;
186 spbr = clamp(tmp, 0, 255);
187
188 return spbr;
189}
190
191static void rspi_enable_irq(struct rspi_data *rspi, u8 enable)
192{
193 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | enable, RSPI_SPCR);
194}
195
196static void rspi_disable_irq(struct rspi_data *rspi, u8 disable)
197{
198 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~disable, RSPI_SPCR);
199}
200
201static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask,
202 u8 enable_bit)
203{
204 int ret;
205
206 rspi->spsr = rspi_read8(rspi, RSPI_SPSR);
207 rspi_enable_irq(rspi, enable_bit);
208 ret = wait_event_timeout(rspi->wait, rspi->spsr & wait_mask, HZ);
209 if (ret == 0 && !(rspi->spsr & wait_mask))
210 return -ETIMEDOUT;
211
212 return 0;
213}
214
215static void rspi_assert_ssl(struct rspi_data *rspi)
216{
217 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR);
218}
219
220static void rspi_negate_ssl(struct rspi_data *rspi)
221{
222 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR);
223}
224
225static int rspi_set_config_register(struct rspi_data *rspi, int access_size)
226{
227 /* Sets output mode(CMOS) and MOSI signal(from previous transfer) */
228 rspi_write8(rspi, 0x00, RSPI_SPPCR);
229
230 /* Sets transfer bit rate */
231 rspi_write8(rspi, rspi_calc_spbr(rspi), RSPI_SPBR);
232
233 /* Sets number of frames to be used: 1 frame */
234 rspi_write8(rspi, 0x00, RSPI_SPDCR);
235
236 /* Sets RSPCK, SSL, next-access delay value */
237 rspi_write8(rspi, 0x00, RSPI_SPCKD);
238 rspi_write8(rspi, 0x00, RSPI_SSLND);
239 rspi_write8(rspi, 0x00, RSPI_SPND);
240
241 /* Sets parity, interrupt mask */
242 rspi_write8(rspi, 0x00, RSPI_SPCR2);
243
244 /* Sets SPCMD */
245 rspi_write16(rspi, SPCMD_SPB_8_TO_16(access_size) | SPCMD_SSLKP,
246 RSPI_SPCMD0);
247
248 /* Sets RSPI mode */
249 rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
250
251 return 0;
252}
253
254static int rspi_send_pio(struct rspi_data *rspi, struct spi_message *mesg,
255 struct spi_transfer *t)
256{
257 int remain = t->len;
258 u8 *data;
259
260 data = (u8 *)t->tx_buf;
261 while (remain > 0) {
262 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_TXMD,
263 RSPI_SPCR);
264
265 if (rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE) < 0) {
266 dev_err(&rspi->master->dev,
267 "%s: tx empty timeout\n", __func__);
268 return -ETIMEDOUT;
269 }
270
271 rspi_write16(rspi, *data, RSPI_SPDR);
272 data++;
273 remain--;
274 }
275
276 /* Waiting for the last transmition */
277 rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
278
279 return 0;
280}
281
282static void rspi_dma_complete(void *arg)
283{
284 struct rspi_data *rspi = arg;
285
286 rspi->dma_callbacked = 1;
287 wake_up_interruptible(&rspi->wait);
288}
289
290static int rspi_dma_map_sg(struct scatterlist *sg, void *buf, unsigned len,
291 struct dma_chan *chan,
292 enum dma_transfer_direction dir)
293{
294 sg_init_table(sg, 1);
295 sg_set_buf(sg, buf, len);
296 sg_dma_len(sg) = len;
297 return dma_map_sg(chan->device->dev, sg, 1, dir);
298}
299
300static void rspi_dma_unmap_sg(struct scatterlist *sg, struct dma_chan *chan,
301 enum dma_transfer_direction dir)
302{
303 dma_unmap_sg(chan->device->dev, sg, 1, dir);
304}
305
306static void rspi_memory_to_8bit(void *buf, const void *data, unsigned len)
307{
308 u16 *dst = buf;
309 const u8 *src = data;
310
311 while (len) {
312 *dst++ = (u16)(*src++);
313 len--;
314 }
315}
316
317static void rspi_memory_from_8bit(void *buf, const void *data, unsigned len)
318{
319 u8 *dst = buf;
320 const u16 *src = data;
321
322 while (len) {
323 *dst++ = (u8)*src++;
324 len--;
325 }
326}
327
328static int rspi_send_dma(struct rspi_data *rspi, struct spi_transfer *t)
329{
330 struct scatterlist sg;
331 void *buf = NULL;
332 struct dma_async_tx_descriptor *desc;
333 unsigned len;
334 int ret = 0;
335
336 if (rspi->dma_width_16bit) {
337 /*
338 * If DMAC bus width is 16-bit, the driver allocates a dummy
339 * buffer. And, the driver converts original data into the
340 * DMAC data as the following format:
341 * original data: 1st byte, 2nd byte ...
342 * DMAC data: 1st byte, dummy, 2nd byte, dummy ...
343 */
344 len = t->len * 2;
345 buf = kmalloc(len, GFP_KERNEL);
346 if (!buf)
347 return -ENOMEM;
348 rspi_memory_to_8bit(buf, t->tx_buf, t->len);
349 } else {
350 len = t->len;
351 buf = (void *)t->tx_buf;
352 }
353
354 if (!rspi_dma_map_sg(&sg, buf, len, rspi->chan_tx, DMA_TO_DEVICE)) {
355 ret = -EFAULT;
356 goto end_nomap;
357 }
358 desc = dmaengine_prep_slave_sg(rspi->chan_tx, &sg, 1, DMA_TO_DEVICE,
359 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
360 if (!desc) {
361 ret = -EIO;
362 goto end;
363 }
364
365 /*
366 * DMAC needs SPTIE, but if SPTIE is set, this IRQ routine will be
367 * called. So, this driver disables the IRQ while DMA transfer.
368 */
369 disable_irq(rspi->irq);
370
371 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_TXMD, RSPI_SPCR);
372 rspi_enable_irq(rspi, SPCR_SPTIE);
373 rspi->dma_callbacked = 0;
374
375 desc->callback = rspi_dma_complete;
376 desc->callback_param = rspi;
377 dmaengine_submit(desc);
378 dma_async_issue_pending(rspi->chan_tx);
379
380 ret = wait_event_interruptible_timeout(rspi->wait,
381 rspi->dma_callbacked, HZ);
382 if (ret > 0 && rspi->dma_callbacked)
383 ret = 0;
384 else if (!ret)
385 ret = -ETIMEDOUT;
386 rspi_disable_irq(rspi, SPCR_SPTIE);
387
388 enable_irq(rspi->irq);
389
390end:
391 rspi_dma_unmap_sg(&sg, rspi->chan_tx, DMA_TO_DEVICE);
392end_nomap:
393 if (rspi->dma_width_16bit)
394 kfree(buf);
395
396 return ret;
397}
398
399static void rspi_receive_init(struct rspi_data *rspi)
400{
401 unsigned char spsr;
402
403 spsr = rspi_read8(rspi, RSPI_SPSR);
404 if (spsr & SPSR_SPRF)
405 rspi_read16(rspi, RSPI_SPDR); /* dummy read */
406 if (spsr & SPSR_OVRF)
407 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF,
408 RSPI_SPCR);
409}
410
411static int rspi_receive_pio(struct rspi_data *rspi, struct spi_message *mesg,
412 struct spi_transfer *t)
413{
414 int remain = t->len;
415 u8 *data;
416
417 rspi_receive_init(rspi);
418
419 data = (u8 *)t->rx_buf;
420 while (remain > 0) {
421 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_TXMD,
422 RSPI_SPCR);
423
424 if (rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE) < 0) {
425 dev_err(&rspi->master->dev,
426 "%s: tx empty timeout\n", __func__);
427 return -ETIMEDOUT;
428 }
429 /* dummy write for generate clock */
430 rspi_write16(rspi, 0x00, RSPI_SPDR);
431
432 if (rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE) < 0) {
433 dev_err(&rspi->master->dev,
434 "%s: receive timeout\n", __func__);
435 return -ETIMEDOUT;
436 }
437 /* SPDR allows 16 or 32-bit access only */
438 *data = (u8)rspi_read16(rspi, RSPI_SPDR);
439
440 data++;
441 remain--;
442 }
443
444 return 0;
445}
446
447static int rspi_receive_dma(struct rspi_data *rspi, struct spi_transfer *t)
448{
449 struct scatterlist sg, sg_dummy;
450 void *dummy = NULL, *rx_buf = NULL;
451 struct dma_async_tx_descriptor *desc, *desc_dummy;
452 unsigned len;
453 int ret = 0;
454
455 if (rspi->dma_width_16bit) {
456 /*
457 * If DMAC bus width is 16-bit, the driver allocates a dummy
458 * buffer. And, finally the driver converts the DMAC data into
459 * actual data as the following format:
460 * DMAC data: 1st byte, dummy, 2nd byte, dummy ...
461 * actual data: 1st byte, 2nd byte ...
462 */
463 len = t->len * 2;
464 rx_buf = kmalloc(len, GFP_KERNEL);
465 if (!rx_buf)
466 return -ENOMEM;
467 } else {
468 len = t->len;
469 rx_buf = t->rx_buf;
470 }
471
472 /* prepare dummy transfer to generate SPI clocks */
473 dummy = kzalloc(len, GFP_KERNEL);
474 if (!dummy) {
475 ret = -ENOMEM;
476 goto end_nomap;
477 }
478 if (!rspi_dma_map_sg(&sg_dummy, dummy, len, rspi->chan_tx,
479 DMA_TO_DEVICE)) {
480 ret = -EFAULT;
481 goto end_nomap;
482 }
483 desc_dummy = dmaengine_prep_slave_sg(rspi->chan_tx, &sg_dummy, 1,
484 DMA_TO_DEVICE, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
485 if (!desc_dummy) {
486 ret = -EIO;
487 goto end_dummy_mapped;
488 }
489
490 /* prepare receive transfer */
491 if (!rspi_dma_map_sg(&sg, rx_buf, len, rspi->chan_rx,
492 DMA_FROM_DEVICE)) {
493 ret = -EFAULT;
494 goto end_dummy_mapped;
495
496 }
497 desc = dmaengine_prep_slave_sg(rspi->chan_rx, &sg, 1, DMA_FROM_DEVICE,
498 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
499 if (!desc) {
500 ret = -EIO;
501 goto end;
502 }
503
504 rspi_receive_init(rspi);
505
506 /*
507 * DMAC needs SPTIE, but if SPTIE is set, this IRQ routine will be
508 * called. So, this driver disables the IRQ while DMA transfer.
509 */
510 disable_irq(rspi->irq);
511
512 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_TXMD, RSPI_SPCR);
513 rspi_enable_irq(rspi, SPCR_SPTIE | SPCR_SPRIE);
514 rspi->dma_callbacked = 0;
515
516 desc->callback = rspi_dma_complete;
517 desc->callback_param = rspi;
518 dmaengine_submit(desc);
519 dma_async_issue_pending(rspi->chan_rx);
520
521 desc_dummy->callback = NULL; /* No callback */
522 dmaengine_submit(desc_dummy);
523 dma_async_issue_pending(rspi->chan_tx);
524
525 ret = wait_event_interruptible_timeout(rspi->wait,
526 rspi->dma_callbacked, HZ);
527 if (ret > 0 && rspi->dma_callbacked)
528 ret = 0;
529 else if (!ret)
530 ret = -ETIMEDOUT;
531 rspi_disable_irq(rspi, SPCR_SPTIE | SPCR_SPRIE);
532
533 enable_irq(rspi->irq);
534
535end:
536 rspi_dma_unmap_sg(&sg, rspi->chan_rx, DMA_FROM_DEVICE);
537end_dummy_mapped:
538 rspi_dma_unmap_sg(&sg_dummy, rspi->chan_tx, DMA_TO_DEVICE);
539end_nomap:
540 if (rspi->dma_width_16bit) {
541 if (!ret)
542 rspi_memory_from_8bit(t->rx_buf, rx_buf, t->len);
543 kfree(rx_buf);
544 }
545 kfree(dummy);
546
547 return ret;
548}
549
550static int rspi_is_dma(struct rspi_data *rspi, struct spi_transfer *t)
551{
552 if (t->tx_buf && rspi->chan_tx)
553 return 1;
554 /* If the module receives data by DMAC, it also needs TX DMAC */
555 if (t->rx_buf && rspi->chan_tx && rspi->chan_rx)
556 return 1;
557
558 return 0;
559}
560
561static void rspi_work(struct work_struct *work)
562{
563 struct rspi_data *rspi = container_of(work, struct rspi_data, ws);
564 struct spi_message *mesg;
565 struct spi_transfer *t;
566 unsigned long flags;
567 int ret;
568
569 spin_lock_irqsave(&rspi->lock, flags);
570 while (!list_empty(&rspi->queue)) {
571 mesg = list_entry(rspi->queue.next, struct spi_message, queue);
572 list_del_init(&mesg->queue);
573 spin_unlock_irqrestore(&rspi->lock, flags);
574
575 rspi_assert_ssl(rspi);
576
577 list_for_each_entry(t, &mesg->transfers, transfer_list) {
578 if (t->tx_buf) {
579 if (rspi_is_dma(rspi, t))
580 ret = rspi_send_dma(rspi, t);
581 else
582 ret = rspi_send_pio(rspi, mesg, t);
583 if (ret < 0)
584 goto error;
585 }
586 if (t->rx_buf) {
587 if (rspi_is_dma(rspi, t))
588 ret = rspi_receive_dma(rspi, t);
589 else
590 ret = rspi_receive_pio(rspi, mesg, t);
591 if (ret < 0)
592 goto error;
593 }
594 mesg->actual_length += t->len;
595 }
596 rspi_negate_ssl(rspi);
597
598 mesg->status = 0;
599 mesg->complete(mesg->context);
600
601 spin_lock_irqsave(&rspi->lock, flags);
602 }
603
604 return;
605
606error:
607 mesg->status = ret;
608 mesg->complete(mesg->context);
609}
610
611static int rspi_setup(struct spi_device *spi)
612{
613 struct rspi_data *rspi = spi_master_get_devdata(spi->master);
614
615 if (!spi->bits_per_word)
616 spi->bits_per_word = 8;
617 rspi->max_speed_hz = spi->max_speed_hz;
618
619 rspi_set_config_register(rspi, 8);
620
621 return 0;
622}
623
624static int rspi_transfer(struct spi_device *spi, struct spi_message *mesg)
625{
626 struct rspi_data *rspi = spi_master_get_devdata(spi->master);
627 unsigned long flags;
628
629 mesg->actual_length = 0;
630 mesg->status = -EINPROGRESS;
631
632 spin_lock_irqsave(&rspi->lock, flags);
633 list_add_tail(&mesg->queue, &rspi->queue);
634 schedule_work(&rspi->ws);
635 spin_unlock_irqrestore(&rspi->lock, flags);
636
637 return 0;
638}
639
640static void rspi_cleanup(struct spi_device *spi)
641{
642}
643
644static irqreturn_t rspi_irq(int irq, void *_sr)
645{
646 struct rspi_data *rspi = (struct rspi_data *)_sr;
647 unsigned long spsr;
648 irqreturn_t ret = IRQ_NONE;
649 unsigned char disable_irq = 0;
650
651 rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
652 if (spsr & SPSR_SPRF)
653 disable_irq |= SPCR_SPRIE;
654 if (spsr & SPSR_SPTEF)
655 disable_irq |= SPCR_SPTIE;
656
657 if (disable_irq) {
658 ret = IRQ_HANDLED;
659 rspi_disable_irq(rspi, disable_irq);
660 wake_up(&rspi->wait);
661 }
662
663 return ret;
664}
665
666static bool rspi_filter(struct dma_chan *chan, void *filter_param)
667{
668 chan->private = filter_param;
669 return true;
670}
671
672static void __devinit rspi_request_dma(struct rspi_data *rspi,
673 struct platform_device *pdev)
674{
675 struct rspi_plat_data *rspi_pd = pdev->dev.platform_data;
676 dma_cap_mask_t mask;
677
678 if (!rspi_pd)
679 return;
680
681 rspi->dma_width_16bit = rspi_pd->dma_width_16bit;
682
683 /* If the module receives data by DMAC, it also needs TX DMAC */
684 if (rspi_pd->dma_rx_id && rspi_pd->dma_tx_id) {
685 dma_cap_zero(mask);
686 dma_cap_set(DMA_SLAVE, mask);
687 rspi->dma_rx.slave_id = rspi_pd->dma_rx_id;
688 rspi->chan_rx = dma_request_channel(mask, rspi_filter,
689 &rspi->dma_rx);
690 if (rspi->chan_rx)
691 dev_info(&pdev->dev, "Use DMA when rx.\n");
692 }
693 if (rspi_pd->dma_tx_id) {
694 dma_cap_zero(mask);
695 dma_cap_set(DMA_SLAVE, mask);
696 rspi->dma_tx.slave_id = rspi_pd->dma_tx_id;
697 rspi->chan_tx = dma_request_channel(mask, rspi_filter,
698 &rspi->dma_tx);
699 if (rspi->chan_tx)
700 dev_info(&pdev->dev, "Use DMA when tx\n");
701 }
702}
703
704static void __devexit rspi_release_dma(struct rspi_data *rspi)
705{
706 if (rspi->chan_tx)
707 dma_release_channel(rspi->chan_tx);
708 if (rspi->chan_rx)
709 dma_release_channel(rspi->chan_rx);
710}
711
712static int __devexit rspi_remove(struct platform_device *pdev)
713{
714 struct rspi_data *rspi = dev_get_drvdata(&pdev->dev);
715
716 spi_unregister_master(rspi->master);
717 rspi_release_dma(rspi);
718 free_irq(platform_get_irq(pdev, 0), rspi);
719 clk_put(rspi->clk);
720 iounmap(rspi->addr);
721 spi_master_put(rspi->master);
722
723 return 0;
724}
725
726static int __devinit rspi_probe(struct platform_device *pdev)
727{
728 struct resource *res;
729 struct spi_master *master;
730 struct rspi_data *rspi;
731 int ret, irq;
732 char clk_name[16];
733
734 /* get base addr */
735 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
736 if (unlikely(res == NULL)) {
737 dev_err(&pdev->dev, "invalid resource\n");
738 return -EINVAL;
739 }
740
741 irq = platform_get_irq(pdev, 0);
742 if (irq < 0) {
743 dev_err(&pdev->dev, "platform_get_irq error\n");
744 return -ENODEV;
745 }
746
747 master = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data));
748 if (master == NULL) {
749 dev_err(&pdev->dev, "spi_alloc_master error.\n");
750 return -ENOMEM;
751 }
752
753 rspi = spi_master_get_devdata(master);
754 dev_set_drvdata(&pdev->dev, rspi);
755
756 rspi->master = master;
757 rspi->addr = ioremap(res->start, resource_size(res));
758 if (rspi->addr == NULL) {
759 dev_err(&pdev->dev, "ioremap error.\n");
760 ret = -ENOMEM;
761 goto error1;
762 }
763
764 snprintf(clk_name, sizeof(clk_name), "rspi%d", pdev->id);
765 rspi->clk = clk_get(&pdev->dev, clk_name);
766 if (IS_ERR(rspi->clk)) {
767 dev_err(&pdev->dev, "cannot get clock\n");
768 ret = PTR_ERR(rspi->clk);
769 goto error2;
770 }
771 clk_enable(rspi->clk);
772
773 INIT_LIST_HEAD(&rspi->queue);
774 spin_lock_init(&rspi->lock);
775 INIT_WORK(&rspi->ws, rspi_work);
776 init_waitqueue_head(&rspi->wait);
777
778 master->num_chipselect = 2;
779 master->bus_num = pdev->id;
780 master->setup = rspi_setup;
781 master->transfer = rspi_transfer;
782 master->cleanup = rspi_cleanup;
783
784 ret = request_irq(irq, rspi_irq, 0, dev_name(&pdev->dev), rspi);
785 if (ret < 0) {
786 dev_err(&pdev->dev, "request_irq error\n");
787 goto error3;
788 }
789
790 rspi->irq = irq;
791 rspi_request_dma(rspi, pdev);
792
793 ret = spi_register_master(master);
794 if (ret < 0) {
795 dev_err(&pdev->dev, "spi_register_master error.\n");
796 goto error4;
797 }
798
799 dev_info(&pdev->dev, "probed\n");
800
801 return 0;
802
803error4:
804 rspi_release_dma(rspi);
805 free_irq(irq, rspi);
806error3:
807 clk_put(rspi->clk);
808error2:
809 iounmap(rspi->addr);
810error1:
811 spi_master_put(master);
812
813 return ret;
814}
815
816static struct platform_driver rspi_driver = {
817 .probe = rspi_probe,
818 .remove = __devexit_p(rspi_remove),
819 .driver = {
820 .name = "rspi",
821 .owner = THIS_MODULE,
822 },
823};
824module_platform_driver(rspi_driver);
825
826MODULE_DESCRIPTION("Renesas RSPI bus driver");
827MODULE_LICENSE("GPL v2");
828MODULE_AUTHOR("Yoshihiro Shimoda");
829MODULE_ALIAS("platform:rspi");