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spi: omap2-mcspi: Fix set_cs function for active high
[deliverable/linux.git] / drivers / spi / spi-omap2-mcspi.c
1 /*
2 * OMAP2 McSPI controller driver
3 *
4 * Copyright (C) 2005, 2006 Nokia Corporation
5 * Author: Samuel Ortiz <samuel.ortiz@nokia.com> and
6 * Juha Yrj�l� <juha.yrjola@nokia.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
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
19 #include <linux/kernel.h>
20 #include <linux/interrupt.h>
21 #include <linux/module.h>
22 #include <linux/device.h>
23 #include <linux/delay.h>
24 #include <linux/dma-mapping.h>
25 #include <linux/dmaengine.h>
26 #include <linux/omap-dma.h>
27 #include <linux/platform_device.h>
28 #include <linux/err.h>
29 #include <linux/clk.h>
30 #include <linux/io.h>
31 #include <linux/slab.h>
32 #include <linux/pm_runtime.h>
33 #include <linux/of.h>
34 #include <linux/of_device.h>
35 #include <linux/gcd.h>
36
37 #include <linux/spi/spi.h>
38 #include <linux/gpio.h>
39
40 #include <linux/platform_data/spi-omap2-mcspi.h>
41
42 #define OMAP2_MCSPI_MAX_FREQ 48000000
43 #define OMAP2_MCSPI_MAX_DIVIDER 4096
44 #define OMAP2_MCSPI_MAX_FIFODEPTH 64
45 #define OMAP2_MCSPI_MAX_FIFOWCNT 0xFFFF
46 #define SPI_AUTOSUSPEND_TIMEOUT 2000
47
48 #define OMAP2_MCSPI_REVISION 0x00
49 #define OMAP2_MCSPI_SYSSTATUS 0x14
50 #define OMAP2_MCSPI_IRQSTATUS 0x18
51 #define OMAP2_MCSPI_IRQENABLE 0x1c
52 #define OMAP2_MCSPI_WAKEUPENABLE 0x20
53 #define OMAP2_MCSPI_SYST 0x24
54 #define OMAP2_MCSPI_MODULCTRL 0x28
55 #define OMAP2_MCSPI_XFERLEVEL 0x7c
56
57 /* per-channel banks, 0x14 bytes each, first is: */
58 #define OMAP2_MCSPI_CHCONF0 0x2c
59 #define OMAP2_MCSPI_CHSTAT0 0x30
60 #define OMAP2_MCSPI_CHCTRL0 0x34
61 #define OMAP2_MCSPI_TX0 0x38
62 #define OMAP2_MCSPI_RX0 0x3c
63
64 /* per-register bitmasks: */
65 #define OMAP2_MCSPI_IRQSTATUS_EOW BIT(17)
66
67 #define OMAP2_MCSPI_MODULCTRL_SINGLE BIT(0)
68 #define OMAP2_MCSPI_MODULCTRL_MS BIT(2)
69 #define OMAP2_MCSPI_MODULCTRL_STEST BIT(3)
70
71 #define OMAP2_MCSPI_CHCONF_PHA BIT(0)
72 #define OMAP2_MCSPI_CHCONF_POL BIT(1)
73 #define OMAP2_MCSPI_CHCONF_CLKD_MASK (0x0f << 2)
74 #define OMAP2_MCSPI_CHCONF_EPOL BIT(6)
75 #define OMAP2_MCSPI_CHCONF_WL_MASK (0x1f << 7)
76 #define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY BIT(12)
77 #define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY BIT(13)
78 #define OMAP2_MCSPI_CHCONF_TRM_MASK (0x03 << 12)
79 #define OMAP2_MCSPI_CHCONF_DMAW BIT(14)
80 #define OMAP2_MCSPI_CHCONF_DMAR BIT(15)
81 #define OMAP2_MCSPI_CHCONF_DPE0 BIT(16)
82 #define OMAP2_MCSPI_CHCONF_DPE1 BIT(17)
83 #define OMAP2_MCSPI_CHCONF_IS BIT(18)
84 #define OMAP2_MCSPI_CHCONF_TURBO BIT(19)
85 #define OMAP2_MCSPI_CHCONF_FORCE BIT(20)
86 #define OMAP2_MCSPI_CHCONF_FFET BIT(27)
87 #define OMAP2_MCSPI_CHCONF_FFER BIT(28)
88 #define OMAP2_MCSPI_CHCONF_CLKG BIT(29)
89
90 #define OMAP2_MCSPI_CHSTAT_RXS BIT(0)
91 #define OMAP2_MCSPI_CHSTAT_TXS BIT(1)
92 #define OMAP2_MCSPI_CHSTAT_EOT BIT(2)
93 #define OMAP2_MCSPI_CHSTAT_TXFFE BIT(3)
94
95 #define OMAP2_MCSPI_CHCTRL_EN BIT(0)
96 #define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK (0xff << 8)
97
98 #define OMAP2_MCSPI_WAKEUPENABLE_WKEN BIT(0)
99
100 /* We have 2 DMA channels per CS, one for RX and one for TX */
101 struct omap2_mcspi_dma {
102 struct dma_chan *dma_tx;
103 struct dma_chan *dma_rx;
104
105 int dma_tx_sync_dev;
106 int dma_rx_sync_dev;
107
108 struct completion dma_tx_completion;
109 struct completion dma_rx_completion;
110
111 char dma_rx_ch_name[14];
112 char dma_tx_ch_name[14];
113 };
114
115 /* use PIO for small transfers, avoiding DMA setup/teardown overhead and
116 * cache operations; better heuristics consider wordsize and bitrate.
117 */
118 #define DMA_MIN_BYTES 160
119
120
121 /*
122 * Used for context save and restore, structure members to be updated whenever
123 * corresponding registers are modified.
124 */
125 struct omap2_mcspi_regs {
126 u32 modulctrl;
127 u32 wakeupenable;
128 struct list_head cs;
129 };
130
131 struct omap2_mcspi {
132 struct spi_master *master;
133 /* Virtual base address of the controller */
134 void __iomem *base;
135 unsigned long phys;
136 /* SPI1 has 4 channels, while SPI2 has 2 */
137 struct omap2_mcspi_dma *dma_channels;
138 struct device *dev;
139 struct omap2_mcspi_regs ctx;
140 int fifo_depth;
141 unsigned int pin_dir:1;
142 };
143
144 struct omap2_mcspi_cs {
145 void __iomem *base;
146 unsigned long phys;
147 int word_len;
148 u16 mode;
149 struct list_head node;
150 /* Context save and restore shadow register */
151 u32 chconf0, chctrl0;
152 };
153
154 static inline void mcspi_write_reg(struct spi_master *master,
155 int idx, u32 val)
156 {
157 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
158
159 writel_relaxed(val, mcspi->base + idx);
160 }
161
162 static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
163 {
164 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
165
166 return readl_relaxed(mcspi->base + idx);
167 }
168
169 static inline void mcspi_write_cs_reg(const struct spi_device *spi,
170 int idx, u32 val)
171 {
172 struct omap2_mcspi_cs *cs = spi->controller_state;
173
174 writel_relaxed(val, cs->base + idx);
175 }
176
177 static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
178 {
179 struct omap2_mcspi_cs *cs = spi->controller_state;
180
181 return readl_relaxed(cs->base + idx);
182 }
183
184 static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
185 {
186 struct omap2_mcspi_cs *cs = spi->controller_state;
187
188 return cs->chconf0;
189 }
190
191 static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
192 {
193 struct omap2_mcspi_cs *cs = spi->controller_state;
194
195 cs->chconf0 = val;
196 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
197 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
198 }
199
200 static inline int mcspi_bytes_per_word(int word_len)
201 {
202 if (word_len <= 8)
203 return 1;
204 else if (word_len <= 16)
205 return 2;
206 else /* word_len <= 32 */
207 return 4;
208 }
209
210 static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
211 int is_read, int enable)
212 {
213 u32 l, rw;
214
215 l = mcspi_cached_chconf0(spi);
216
217 if (is_read) /* 1 is read, 0 write */
218 rw = OMAP2_MCSPI_CHCONF_DMAR;
219 else
220 rw = OMAP2_MCSPI_CHCONF_DMAW;
221
222 if (enable)
223 l |= rw;
224 else
225 l &= ~rw;
226
227 mcspi_write_chconf0(spi, l);
228 }
229
230 static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
231 {
232 struct omap2_mcspi_cs *cs = spi->controller_state;
233 u32 l;
234
235 l = cs->chctrl0;
236 if (enable)
237 l |= OMAP2_MCSPI_CHCTRL_EN;
238 else
239 l &= ~OMAP2_MCSPI_CHCTRL_EN;
240 cs->chctrl0 = l;
241 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
242 /* Flash post-writes */
243 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
244 }
245
246 static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable)
247 {
248 u32 l;
249
250 /* The controller handles the inverted chip selects
251 * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert
252 * the inversion from the core spi_set_cs function.
253 */
254 if (spi->mode & SPI_CS_HIGH)
255 enable = !enable;
256
257 if (spi->controller_state) {
258 l = mcspi_cached_chconf0(spi);
259
260 if (enable)
261 l &= ~OMAP2_MCSPI_CHCONF_FORCE;
262 else
263 l |= OMAP2_MCSPI_CHCONF_FORCE;
264
265 mcspi_write_chconf0(spi, l);
266 }
267 }
268
269 static void omap2_mcspi_set_master_mode(struct spi_master *master)
270 {
271 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
272 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
273 u32 l;
274
275 /*
276 * Setup when switching from (reset default) slave mode
277 * to single-channel master mode
278 */
279 l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
280 l &= ~(OMAP2_MCSPI_MODULCTRL_STEST | OMAP2_MCSPI_MODULCTRL_MS);
281 l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
282 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
283
284 ctx->modulctrl = l;
285 }
286
287 static void omap2_mcspi_set_fifo(const struct spi_device *spi,
288 struct spi_transfer *t, int enable)
289 {
290 struct spi_master *master = spi->master;
291 struct omap2_mcspi_cs *cs = spi->controller_state;
292 struct omap2_mcspi *mcspi;
293 unsigned int wcnt;
294 int max_fifo_depth, fifo_depth, bytes_per_word;
295 u32 chconf, xferlevel;
296
297 mcspi = spi_master_get_devdata(master);
298
299 chconf = mcspi_cached_chconf0(spi);
300 if (enable) {
301 bytes_per_word = mcspi_bytes_per_word(cs->word_len);
302 if (t->len % bytes_per_word != 0)
303 goto disable_fifo;
304
305 if (t->rx_buf != NULL && t->tx_buf != NULL)
306 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
307 else
308 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
309
310 fifo_depth = gcd(t->len, max_fifo_depth);
311 if (fifo_depth < 2 || fifo_depth % bytes_per_word != 0)
312 goto disable_fifo;
313
314 wcnt = t->len / bytes_per_word;
315 if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
316 goto disable_fifo;
317
318 xferlevel = wcnt << 16;
319 if (t->rx_buf != NULL) {
320 chconf |= OMAP2_MCSPI_CHCONF_FFER;
321 xferlevel |= (fifo_depth - 1) << 8;
322 }
323 if (t->tx_buf != NULL) {
324 chconf |= OMAP2_MCSPI_CHCONF_FFET;
325 xferlevel |= fifo_depth - 1;
326 }
327
328 mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel);
329 mcspi_write_chconf0(spi, chconf);
330 mcspi->fifo_depth = fifo_depth;
331
332 return;
333 }
334
335 disable_fifo:
336 if (t->rx_buf != NULL)
337 chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
338
339 if (t->tx_buf != NULL)
340 chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
341
342 mcspi_write_chconf0(spi, chconf);
343 mcspi->fifo_depth = 0;
344 }
345
346 static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
347 {
348 struct spi_master *spi_cntrl = mcspi->master;
349 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
350 struct omap2_mcspi_cs *cs;
351
352 /* McSPI: context restore */
353 mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
354 mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
355
356 list_for_each_entry(cs, &ctx->cs, node)
357 writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
358 }
359
360 static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
361 {
362 unsigned long timeout;
363
364 timeout = jiffies + msecs_to_jiffies(1000);
365 while (!(readl_relaxed(reg) & bit)) {
366 if (time_after(jiffies, timeout)) {
367 if (!(readl_relaxed(reg) & bit))
368 return -ETIMEDOUT;
369 else
370 return 0;
371 }
372 cpu_relax();
373 }
374 return 0;
375 }
376
377 static void omap2_mcspi_rx_callback(void *data)
378 {
379 struct spi_device *spi = data;
380 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
381 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
382
383 /* We must disable the DMA RX request */
384 omap2_mcspi_set_dma_req(spi, 1, 0);
385
386 complete(&mcspi_dma->dma_rx_completion);
387 }
388
389 static void omap2_mcspi_tx_callback(void *data)
390 {
391 struct spi_device *spi = data;
392 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
393 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
394
395 /* We must disable the DMA TX request */
396 omap2_mcspi_set_dma_req(spi, 0, 0);
397
398 complete(&mcspi_dma->dma_tx_completion);
399 }
400
401 static void omap2_mcspi_tx_dma(struct spi_device *spi,
402 struct spi_transfer *xfer,
403 struct dma_slave_config cfg)
404 {
405 struct omap2_mcspi *mcspi;
406 struct omap2_mcspi_dma *mcspi_dma;
407 unsigned int count;
408
409 mcspi = spi_master_get_devdata(spi->master);
410 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
411 count = xfer->len;
412
413 if (mcspi_dma->dma_tx) {
414 struct dma_async_tx_descriptor *tx;
415 struct scatterlist sg;
416
417 dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
418
419 sg_init_table(&sg, 1);
420 sg_dma_address(&sg) = xfer->tx_dma;
421 sg_dma_len(&sg) = xfer->len;
422
423 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, &sg, 1,
424 DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
425 if (tx) {
426 tx->callback = omap2_mcspi_tx_callback;
427 tx->callback_param = spi;
428 dmaengine_submit(tx);
429 } else {
430 /* FIXME: fall back to PIO? */
431 }
432 }
433 dma_async_issue_pending(mcspi_dma->dma_tx);
434 omap2_mcspi_set_dma_req(spi, 0, 1);
435
436 }
437
438 static unsigned
439 omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
440 struct dma_slave_config cfg,
441 unsigned es)
442 {
443 struct omap2_mcspi *mcspi;
444 struct omap2_mcspi_dma *mcspi_dma;
445 unsigned int count, dma_count;
446 u32 l;
447 int elements = 0;
448 int word_len, element_count;
449 struct omap2_mcspi_cs *cs = spi->controller_state;
450 mcspi = spi_master_get_devdata(spi->master);
451 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
452 count = xfer->len;
453 dma_count = xfer->len;
454
455 if (mcspi->fifo_depth == 0)
456 dma_count -= es;
457
458 word_len = cs->word_len;
459 l = mcspi_cached_chconf0(spi);
460
461 if (word_len <= 8)
462 element_count = count;
463 else if (word_len <= 16)
464 element_count = count >> 1;
465 else /* word_len <= 32 */
466 element_count = count >> 2;
467
468 if (mcspi_dma->dma_rx) {
469 struct dma_async_tx_descriptor *tx;
470 struct scatterlist sg;
471
472 dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
473
474 if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
475 dma_count -= es;
476
477 sg_init_table(&sg, 1);
478 sg_dma_address(&sg) = xfer->rx_dma;
479 sg_dma_len(&sg) = dma_count;
480
481 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, &sg, 1,
482 DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT |
483 DMA_CTRL_ACK);
484 if (tx) {
485 tx->callback = omap2_mcspi_rx_callback;
486 tx->callback_param = spi;
487 dmaengine_submit(tx);
488 } else {
489 /* FIXME: fall back to PIO? */
490 }
491 }
492
493 dma_async_issue_pending(mcspi_dma->dma_rx);
494 omap2_mcspi_set_dma_req(spi, 1, 1);
495
496 wait_for_completion(&mcspi_dma->dma_rx_completion);
497 dma_unmap_single(mcspi->dev, xfer->rx_dma, count,
498 DMA_FROM_DEVICE);
499
500 if (mcspi->fifo_depth > 0)
501 return count;
502
503 omap2_mcspi_set_enable(spi, 0);
504
505 elements = element_count - 1;
506
507 if (l & OMAP2_MCSPI_CHCONF_TURBO) {
508 elements--;
509
510 if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
511 & OMAP2_MCSPI_CHSTAT_RXS)) {
512 u32 w;
513
514 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
515 if (word_len <= 8)
516 ((u8 *)xfer->rx_buf)[elements++] = w;
517 else if (word_len <= 16)
518 ((u16 *)xfer->rx_buf)[elements++] = w;
519 else /* word_len <= 32 */
520 ((u32 *)xfer->rx_buf)[elements++] = w;
521 } else {
522 int bytes_per_word = mcspi_bytes_per_word(word_len);
523 dev_err(&spi->dev, "DMA RX penultimate word empty\n");
524 count -= (bytes_per_word << 1);
525 omap2_mcspi_set_enable(spi, 1);
526 return count;
527 }
528 }
529 if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
530 & OMAP2_MCSPI_CHSTAT_RXS)) {
531 u32 w;
532
533 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
534 if (word_len <= 8)
535 ((u8 *)xfer->rx_buf)[elements] = w;
536 else if (word_len <= 16)
537 ((u16 *)xfer->rx_buf)[elements] = w;
538 else /* word_len <= 32 */
539 ((u32 *)xfer->rx_buf)[elements] = w;
540 } else {
541 dev_err(&spi->dev, "DMA RX last word empty\n");
542 count -= mcspi_bytes_per_word(word_len);
543 }
544 omap2_mcspi_set_enable(spi, 1);
545 return count;
546 }
547
548 static unsigned
549 omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
550 {
551 struct omap2_mcspi *mcspi;
552 struct omap2_mcspi_cs *cs = spi->controller_state;
553 struct omap2_mcspi_dma *mcspi_dma;
554 unsigned int count;
555 u32 l;
556 u8 *rx;
557 const u8 *tx;
558 struct dma_slave_config cfg;
559 enum dma_slave_buswidth width;
560 unsigned es;
561 u32 burst;
562 void __iomem *chstat_reg;
563 void __iomem *irqstat_reg;
564 int wait_res;
565
566 mcspi = spi_master_get_devdata(spi->master);
567 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
568 l = mcspi_cached_chconf0(spi);
569
570
571 if (cs->word_len <= 8) {
572 width = DMA_SLAVE_BUSWIDTH_1_BYTE;
573 es = 1;
574 } else if (cs->word_len <= 16) {
575 width = DMA_SLAVE_BUSWIDTH_2_BYTES;
576 es = 2;
577 } else {
578 width = DMA_SLAVE_BUSWIDTH_4_BYTES;
579 es = 4;
580 }
581
582 count = xfer->len;
583 burst = 1;
584
585 if (mcspi->fifo_depth > 0) {
586 if (count > mcspi->fifo_depth)
587 burst = mcspi->fifo_depth / es;
588 else
589 burst = count / es;
590 }
591
592 memset(&cfg, 0, sizeof(cfg));
593 cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
594 cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
595 cfg.src_addr_width = width;
596 cfg.dst_addr_width = width;
597 cfg.src_maxburst = burst;
598 cfg.dst_maxburst = burst;
599
600 rx = xfer->rx_buf;
601 tx = xfer->tx_buf;
602
603 if (tx != NULL)
604 omap2_mcspi_tx_dma(spi, xfer, cfg);
605
606 if (rx != NULL)
607 count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
608
609 if (tx != NULL) {
610 wait_for_completion(&mcspi_dma->dma_tx_completion);
611 dma_unmap_single(mcspi->dev, xfer->tx_dma, xfer->len,
612 DMA_TO_DEVICE);
613
614 if (mcspi->fifo_depth > 0) {
615 irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
616
617 if (mcspi_wait_for_reg_bit(irqstat_reg,
618 OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
619 dev_err(&spi->dev, "EOW timed out\n");
620
621 mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
622 OMAP2_MCSPI_IRQSTATUS_EOW);
623 }
624
625 /* for TX_ONLY mode, be sure all words have shifted out */
626 if (rx == NULL) {
627 chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
628 if (mcspi->fifo_depth > 0) {
629 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
630 OMAP2_MCSPI_CHSTAT_TXFFE);
631 if (wait_res < 0)
632 dev_err(&spi->dev, "TXFFE timed out\n");
633 } else {
634 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
635 OMAP2_MCSPI_CHSTAT_TXS);
636 if (wait_res < 0)
637 dev_err(&spi->dev, "TXS timed out\n");
638 }
639 if (wait_res >= 0 &&
640 (mcspi_wait_for_reg_bit(chstat_reg,
641 OMAP2_MCSPI_CHSTAT_EOT) < 0))
642 dev_err(&spi->dev, "EOT timed out\n");
643 }
644 }
645 return count;
646 }
647
648 static unsigned
649 omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
650 {
651 struct omap2_mcspi *mcspi;
652 struct omap2_mcspi_cs *cs = spi->controller_state;
653 unsigned int count, c;
654 u32 l;
655 void __iomem *base = cs->base;
656 void __iomem *tx_reg;
657 void __iomem *rx_reg;
658 void __iomem *chstat_reg;
659 int word_len;
660
661 mcspi = spi_master_get_devdata(spi->master);
662 count = xfer->len;
663 c = count;
664 word_len = cs->word_len;
665
666 l = mcspi_cached_chconf0(spi);
667
668 /* We store the pre-calculated register addresses on stack to speed
669 * up the transfer loop. */
670 tx_reg = base + OMAP2_MCSPI_TX0;
671 rx_reg = base + OMAP2_MCSPI_RX0;
672 chstat_reg = base + OMAP2_MCSPI_CHSTAT0;
673
674 if (c < (word_len>>3))
675 return 0;
676
677 if (word_len <= 8) {
678 u8 *rx;
679 const u8 *tx;
680
681 rx = xfer->rx_buf;
682 tx = xfer->tx_buf;
683
684 do {
685 c -= 1;
686 if (tx != NULL) {
687 if (mcspi_wait_for_reg_bit(chstat_reg,
688 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
689 dev_err(&spi->dev, "TXS timed out\n");
690 goto out;
691 }
692 dev_vdbg(&spi->dev, "write-%d %02x\n",
693 word_len, *tx);
694 writel_relaxed(*tx++, tx_reg);
695 }
696 if (rx != NULL) {
697 if (mcspi_wait_for_reg_bit(chstat_reg,
698 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
699 dev_err(&spi->dev, "RXS timed out\n");
700 goto out;
701 }
702
703 if (c == 1 && tx == NULL &&
704 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
705 omap2_mcspi_set_enable(spi, 0);
706 *rx++ = readl_relaxed(rx_reg);
707 dev_vdbg(&spi->dev, "read-%d %02x\n",
708 word_len, *(rx - 1));
709 if (mcspi_wait_for_reg_bit(chstat_reg,
710 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
711 dev_err(&spi->dev,
712 "RXS timed out\n");
713 goto out;
714 }
715 c = 0;
716 } else if (c == 0 && tx == NULL) {
717 omap2_mcspi_set_enable(spi, 0);
718 }
719
720 *rx++ = readl_relaxed(rx_reg);
721 dev_vdbg(&spi->dev, "read-%d %02x\n",
722 word_len, *(rx - 1));
723 }
724 } while (c);
725 } else if (word_len <= 16) {
726 u16 *rx;
727 const u16 *tx;
728
729 rx = xfer->rx_buf;
730 tx = xfer->tx_buf;
731 do {
732 c -= 2;
733 if (tx != NULL) {
734 if (mcspi_wait_for_reg_bit(chstat_reg,
735 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
736 dev_err(&spi->dev, "TXS timed out\n");
737 goto out;
738 }
739 dev_vdbg(&spi->dev, "write-%d %04x\n",
740 word_len, *tx);
741 writel_relaxed(*tx++, tx_reg);
742 }
743 if (rx != NULL) {
744 if (mcspi_wait_for_reg_bit(chstat_reg,
745 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
746 dev_err(&spi->dev, "RXS timed out\n");
747 goto out;
748 }
749
750 if (c == 2 && tx == NULL &&
751 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
752 omap2_mcspi_set_enable(spi, 0);
753 *rx++ = readl_relaxed(rx_reg);
754 dev_vdbg(&spi->dev, "read-%d %04x\n",
755 word_len, *(rx - 1));
756 if (mcspi_wait_for_reg_bit(chstat_reg,
757 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
758 dev_err(&spi->dev,
759 "RXS timed out\n");
760 goto out;
761 }
762 c = 0;
763 } else if (c == 0 && tx == NULL) {
764 omap2_mcspi_set_enable(spi, 0);
765 }
766
767 *rx++ = readl_relaxed(rx_reg);
768 dev_vdbg(&spi->dev, "read-%d %04x\n",
769 word_len, *(rx - 1));
770 }
771 } while (c >= 2);
772 } else if (word_len <= 32) {
773 u32 *rx;
774 const u32 *tx;
775
776 rx = xfer->rx_buf;
777 tx = xfer->tx_buf;
778 do {
779 c -= 4;
780 if (tx != NULL) {
781 if (mcspi_wait_for_reg_bit(chstat_reg,
782 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
783 dev_err(&spi->dev, "TXS timed out\n");
784 goto out;
785 }
786 dev_vdbg(&spi->dev, "write-%d %08x\n",
787 word_len, *tx);
788 writel_relaxed(*tx++, tx_reg);
789 }
790 if (rx != NULL) {
791 if (mcspi_wait_for_reg_bit(chstat_reg,
792 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
793 dev_err(&spi->dev, "RXS timed out\n");
794 goto out;
795 }
796
797 if (c == 4 && tx == NULL &&
798 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
799 omap2_mcspi_set_enable(spi, 0);
800 *rx++ = readl_relaxed(rx_reg);
801 dev_vdbg(&spi->dev, "read-%d %08x\n",
802 word_len, *(rx - 1));
803 if (mcspi_wait_for_reg_bit(chstat_reg,
804 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
805 dev_err(&spi->dev,
806 "RXS timed out\n");
807 goto out;
808 }
809 c = 0;
810 } else if (c == 0 && tx == NULL) {
811 omap2_mcspi_set_enable(spi, 0);
812 }
813
814 *rx++ = readl_relaxed(rx_reg);
815 dev_vdbg(&spi->dev, "read-%d %08x\n",
816 word_len, *(rx - 1));
817 }
818 } while (c >= 4);
819 }
820
821 /* for TX_ONLY mode, be sure all words have shifted out */
822 if (xfer->rx_buf == NULL) {
823 if (mcspi_wait_for_reg_bit(chstat_reg,
824 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
825 dev_err(&spi->dev, "TXS timed out\n");
826 } else if (mcspi_wait_for_reg_bit(chstat_reg,
827 OMAP2_MCSPI_CHSTAT_EOT) < 0)
828 dev_err(&spi->dev, "EOT timed out\n");
829
830 /* disable chan to purge rx datas received in TX_ONLY transfer,
831 * otherwise these rx datas will affect the direct following
832 * RX_ONLY transfer.
833 */
834 omap2_mcspi_set_enable(spi, 0);
835 }
836 out:
837 omap2_mcspi_set_enable(spi, 1);
838 return count - c;
839 }
840
841 static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
842 {
843 u32 div;
844
845 for (div = 0; div < 15; div++)
846 if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
847 return div;
848
849 return 15;
850 }
851
852 /* called only when no transfer is active to this device */
853 static int omap2_mcspi_setup_transfer(struct spi_device *spi,
854 struct spi_transfer *t)
855 {
856 struct omap2_mcspi_cs *cs = spi->controller_state;
857 struct omap2_mcspi *mcspi;
858 struct spi_master *spi_cntrl;
859 u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
860 u8 word_len = spi->bits_per_word;
861 u32 speed_hz = spi->max_speed_hz;
862
863 mcspi = spi_master_get_devdata(spi->master);
864 spi_cntrl = mcspi->master;
865
866 if (t != NULL && t->bits_per_word)
867 word_len = t->bits_per_word;
868
869 cs->word_len = word_len;
870
871 if (t && t->speed_hz)
872 speed_hz = t->speed_hz;
873
874 speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
875 if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
876 clkd = omap2_mcspi_calc_divisor(speed_hz);
877 speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
878 clkg = 0;
879 } else {
880 div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
881 speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
882 clkd = (div - 1) & 0xf;
883 extclk = (div - 1) >> 4;
884 clkg = OMAP2_MCSPI_CHCONF_CLKG;
885 }
886
887 l = mcspi_cached_chconf0(spi);
888
889 /* standard 4-wire master mode: SCK, MOSI/out, MISO/in, nCS
890 * REVISIT: this controller could support SPI_3WIRE mode.
891 */
892 if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
893 l &= ~OMAP2_MCSPI_CHCONF_IS;
894 l &= ~OMAP2_MCSPI_CHCONF_DPE1;
895 l |= OMAP2_MCSPI_CHCONF_DPE0;
896 } else {
897 l |= OMAP2_MCSPI_CHCONF_IS;
898 l |= OMAP2_MCSPI_CHCONF_DPE1;
899 l &= ~OMAP2_MCSPI_CHCONF_DPE0;
900 }
901
902 /* wordlength */
903 l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
904 l |= (word_len - 1) << 7;
905
906 /* set chipselect polarity; manage with FORCE */
907 if (!(spi->mode & SPI_CS_HIGH))
908 l |= OMAP2_MCSPI_CHCONF_EPOL; /* active-low; normal */
909 else
910 l &= ~OMAP2_MCSPI_CHCONF_EPOL;
911
912 /* set clock divisor */
913 l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
914 l |= clkd << 2;
915
916 /* set clock granularity */
917 l &= ~OMAP2_MCSPI_CHCONF_CLKG;
918 l |= clkg;
919 if (clkg) {
920 cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
921 cs->chctrl0 |= extclk << 8;
922 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
923 }
924
925 /* set SPI mode 0..3 */
926 if (spi->mode & SPI_CPOL)
927 l |= OMAP2_MCSPI_CHCONF_POL;
928 else
929 l &= ~OMAP2_MCSPI_CHCONF_POL;
930 if (spi->mode & SPI_CPHA)
931 l |= OMAP2_MCSPI_CHCONF_PHA;
932 else
933 l &= ~OMAP2_MCSPI_CHCONF_PHA;
934
935 mcspi_write_chconf0(spi, l);
936
937 cs->mode = spi->mode;
938
939 dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
940 speed_hz,
941 (spi->mode & SPI_CPHA) ? "trailing" : "leading",
942 (spi->mode & SPI_CPOL) ? "inverted" : "normal");
943
944 return 0;
945 }
946
947 /*
948 * Note that we currently allow DMA only if we get a channel
949 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
950 */
951 static int omap2_mcspi_request_dma(struct spi_device *spi)
952 {
953 struct spi_master *master = spi->master;
954 struct omap2_mcspi *mcspi;
955 struct omap2_mcspi_dma *mcspi_dma;
956 dma_cap_mask_t mask;
957 unsigned sig;
958
959 mcspi = spi_master_get_devdata(master);
960 mcspi_dma = mcspi->dma_channels + spi->chip_select;
961
962 init_completion(&mcspi_dma->dma_rx_completion);
963 init_completion(&mcspi_dma->dma_tx_completion);
964
965 dma_cap_zero(mask);
966 dma_cap_set(DMA_SLAVE, mask);
967 sig = mcspi_dma->dma_rx_sync_dev;
968
969 mcspi_dma->dma_rx =
970 dma_request_slave_channel_compat(mask, omap_dma_filter_fn,
971 &sig, &master->dev,
972 mcspi_dma->dma_rx_ch_name);
973 if (!mcspi_dma->dma_rx)
974 goto no_dma;
975
976 sig = mcspi_dma->dma_tx_sync_dev;
977 mcspi_dma->dma_tx =
978 dma_request_slave_channel_compat(mask, omap_dma_filter_fn,
979 &sig, &master->dev,
980 mcspi_dma->dma_tx_ch_name);
981
982 if (!mcspi_dma->dma_tx) {
983 dma_release_channel(mcspi_dma->dma_rx);
984 mcspi_dma->dma_rx = NULL;
985 goto no_dma;
986 }
987
988 return 0;
989
990 no_dma:
991 dev_warn(&spi->dev, "not using DMA for McSPI\n");
992 return -EAGAIN;
993 }
994
995 static int omap2_mcspi_setup(struct spi_device *spi)
996 {
997 int ret;
998 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
999 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1000 struct omap2_mcspi_dma *mcspi_dma;
1001 struct omap2_mcspi_cs *cs = spi->controller_state;
1002
1003 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1004
1005 if (!cs) {
1006 cs = kzalloc(sizeof *cs, GFP_KERNEL);
1007 if (!cs)
1008 return -ENOMEM;
1009 cs->base = mcspi->base + spi->chip_select * 0x14;
1010 cs->phys = mcspi->phys + spi->chip_select * 0x14;
1011 cs->mode = 0;
1012 cs->chconf0 = 0;
1013 cs->chctrl0 = 0;
1014 spi->controller_state = cs;
1015 /* Link this to context save list */
1016 list_add_tail(&cs->node, &ctx->cs);
1017 }
1018
1019 if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) {
1020 ret = omap2_mcspi_request_dma(spi);
1021 if (ret < 0 && ret != -EAGAIN)
1022 return ret;
1023 }
1024
1025 if (gpio_is_valid(spi->cs_gpio)) {
1026 if (gpio_request(spi->cs_gpio, dev_name(&spi->dev)) == 0)
1027 gpio_direction_output(spi->cs_gpio,
1028 !(spi->mode & SPI_CS_HIGH));
1029 }
1030
1031 ret = pm_runtime_get_sync(mcspi->dev);
1032 if (ret < 0)
1033 return ret;
1034
1035 ret = omap2_mcspi_setup_transfer(spi, NULL);
1036 pm_runtime_mark_last_busy(mcspi->dev);
1037 pm_runtime_put_autosuspend(mcspi->dev);
1038
1039 return ret;
1040 }
1041
1042 static void omap2_mcspi_cleanup(struct spi_device *spi)
1043 {
1044 struct omap2_mcspi *mcspi;
1045 struct omap2_mcspi_dma *mcspi_dma;
1046 struct omap2_mcspi_cs *cs;
1047
1048 mcspi = spi_master_get_devdata(spi->master);
1049
1050 if (spi->controller_state) {
1051 /* Unlink controller state from context save list */
1052 cs = spi->controller_state;
1053 list_del(&cs->node);
1054
1055 kfree(cs);
1056 }
1057
1058 if (spi->chip_select < spi->master->num_chipselect) {
1059 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1060
1061 if (mcspi_dma->dma_rx) {
1062 dma_release_channel(mcspi_dma->dma_rx);
1063 mcspi_dma->dma_rx = NULL;
1064 }
1065 if (mcspi_dma->dma_tx) {
1066 dma_release_channel(mcspi_dma->dma_tx);
1067 mcspi_dma->dma_tx = NULL;
1068 }
1069 }
1070
1071 if (gpio_is_valid(spi->cs_gpio))
1072 gpio_free(spi->cs_gpio);
1073 }
1074
1075 static int omap2_mcspi_work_one(struct omap2_mcspi *mcspi,
1076 struct spi_device *spi, struct spi_transfer *t)
1077 {
1078
1079 /* We only enable one channel at a time -- the one whose message is
1080 * -- although this controller would gladly
1081 * arbitrate among multiple channels. This corresponds to "single
1082 * channel" master mode. As a side effect, we need to manage the
1083 * chipselect with the FORCE bit ... CS != channel enable.
1084 */
1085
1086 struct spi_master *master;
1087 struct omap2_mcspi_dma *mcspi_dma;
1088 struct omap2_mcspi_cs *cs;
1089 struct omap2_mcspi_device_config *cd;
1090 int par_override = 0;
1091 int status = 0;
1092 u32 chconf;
1093
1094 master = spi->master;
1095 mcspi_dma = mcspi->dma_channels + spi->chip_select;
1096 cs = spi->controller_state;
1097 cd = spi->controller_data;
1098
1099 /*
1100 * The slave driver could have changed spi->mode in which case
1101 * it will be different from cs->mode (the current hardware setup).
1102 * If so, set par_override (even though its not a parity issue) so
1103 * omap2_mcspi_setup_transfer will be called to configure the hardware
1104 * with the correct mode on the first iteration of the loop below.
1105 */
1106 if (spi->mode != cs->mode)
1107 par_override = 1;
1108
1109 omap2_mcspi_set_enable(spi, 0);
1110
1111 if (par_override ||
1112 (t->speed_hz != spi->max_speed_hz) ||
1113 (t->bits_per_word != spi->bits_per_word)) {
1114 par_override = 1;
1115 status = omap2_mcspi_setup_transfer(spi, t);
1116 if (status < 0)
1117 goto out;
1118 if (t->speed_hz == spi->max_speed_hz &&
1119 t->bits_per_word == spi->bits_per_word)
1120 par_override = 0;
1121 }
1122 if (cd && cd->cs_per_word) {
1123 chconf = mcspi->ctx.modulctrl;
1124 chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1125 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1126 mcspi->ctx.modulctrl =
1127 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1128 }
1129
1130 chconf = mcspi_cached_chconf0(spi);
1131 chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1132 chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
1133
1134 if (t->tx_buf == NULL)
1135 chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1136 else if (t->rx_buf == NULL)
1137 chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1138
1139 if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1140 /* Turbo mode is for more than one word */
1141 if (t->len > ((cs->word_len + 7) >> 3))
1142 chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1143 }
1144
1145 mcspi_write_chconf0(spi, chconf);
1146
1147 if (t->len) {
1148 unsigned count;
1149
1150 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1151 (t->len >= DMA_MIN_BYTES))
1152 omap2_mcspi_set_fifo(spi, t, 1);
1153
1154 omap2_mcspi_set_enable(spi, 1);
1155
1156 /* RX_ONLY mode needs dummy data in TX reg */
1157 if (t->tx_buf == NULL)
1158 writel_relaxed(0, cs->base
1159 + OMAP2_MCSPI_TX0);
1160
1161 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1162 (t->len >= DMA_MIN_BYTES))
1163 count = omap2_mcspi_txrx_dma(spi, t);
1164 else
1165 count = omap2_mcspi_txrx_pio(spi, t);
1166
1167 if (count != t->len) {
1168 status = -EIO;
1169 goto out;
1170 }
1171 }
1172
1173 omap2_mcspi_set_enable(spi, 0);
1174
1175 if (mcspi->fifo_depth > 0)
1176 omap2_mcspi_set_fifo(spi, t, 0);
1177
1178 out:
1179 /* Restore defaults if they were overriden */
1180 if (par_override) {
1181 par_override = 0;
1182 status = omap2_mcspi_setup_transfer(spi, NULL);
1183 }
1184
1185 if (cd && cd->cs_per_word) {
1186 chconf = mcspi->ctx.modulctrl;
1187 chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1188 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1189 mcspi->ctx.modulctrl =
1190 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1191 }
1192
1193 omap2_mcspi_set_enable(spi, 0);
1194
1195 if (mcspi->fifo_depth > 0 && t)
1196 omap2_mcspi_set_fifo(spi, t, 0);
1197
1198 return status;
1199 }
1200
1201 static int omap2_mcspi_transfer_one(struct spi_master *master,
1202 struct spi_device *spi, struct spi_transfer *t)
1203 {
1204 struct omap2_mcspi *mcspi;
1205 struct omap2_mcspi_dma *mcspi_dma;
1206 const void *tx_buf = t->tx_buf;
1207 void *rx_buf = t->rx_buf;
1208 unsigned len = t->len;
1209
1210 mcspi = spi_master_get_devdata(master);
1211 mcspi_dma = mcspi->dma_channels + spi->chip_select;
1212
1213 if ((len && !(rx_buf || tx_buf))) {
1214 dev_dbg(mcspi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
1215 t->speed_hz,
1216 len,
1217 tx_buf ? "tx" : "",
1218 rx_buf ? "rx" : "",
1219 t->bits_per_word);
1220 return -EINVAL;
1221 }
1222
1223 if (len < DMA_MIN_BYTES)
1224 goto skip_dma_map;
1225
1226 if (mcspi_dma->dma_tx && tx_buf != NULL) {
1227 t->tx_dma = dma_map_single(mcspi->dev, (void *) tx_buf,
1228 len, DMA_TO_DEVICE);
1229 if (dma_mapping_error(mcspi->dev, t->tx_dma)) {
1230 dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1231 'T', len);
1232 return -EINVAL;
1233 }
1234 }
1235 if (mcspi_dma->dma_rx && rx_buf != NULL) {
1236 t->rx_dma = dma_map_single(mcspi->dev, rx_buf, t->len,
1237 DMA_FROM_DEVICE);
1238 if (dma_mapping_error(mcspi->dev, t->rx_dma)) {
1239 dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1240 'R', len);
1241 if (tx_buf != NULL)
1242 dma_unmap_single(mcspi->dev, t->tx_dma,
1243 len, DMA_TO_DEVICE);
1244 return -EINVAL;
1245 }
1246 }
1247
1248 skip_dma_map:
1249 return omap2_mcspi_work_one(mcspi, spi, t);
1250 }
1251
1252 static int omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
1253 {
1254 struct spi_master *master = mcspi->master;
1255 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1256 int ret = 0;
1257
1258 ret = pm_runtime_get_sync(mcspi->dev);
1259 if (ret < 0)
1260 return ret;
1261
1262 mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1263 OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1264 ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1265
1266 omap2_mcspi_set_master_mode(master);
1267 pm_runtime_mark_last_busy(mcspi->dev);
1268 pm_runtime_put_autosuspend(mcspi->dev);
1269 return 0;
1270 }
1271
1272 static int omap_mcspi_runtime_resume(struct device *dev)
1273 {
1274 struct omap2_mcspi *mcspi;
1275 struct spi_master *master;
1276
1277 master = dev_get_drvdata(dev);
1278 mcspi = spi_master_get_devdata(master);
1279 omap2_mcspi_restore_ctx(mcspi);
1280
1281 return 0;
1282 }
1283
1284 static struct omap2_mcspi_platform_config omap2_pdata = {
1285 .regs_offset = 0,
1286 };
1287
1288 static struct omap2_mcspi_platform_config omap4_pdata = {
1289 .regs_offset = OMAP4_MCSPI_REG_OFFSET,
1290 };
1291
1292 static const struct of_device_id omap_mcspi_of_match[] = {
1293 {
1294 .compatible = "ti,omap2-mcspi",
1295 .data = &omap2_pdata,
1296 },
1297 {
1298 .compatible = "ti,omap4-mcspi",
1299 .data = &omap4_pdata,
1300 },
1301 { },
1302 };
1303 MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1304
1305 static int omap2_mcspi_probe(struct platform_device *pdev)
1306 {
1307 struct spi_master *master;
1308 const struct omap2_mcspi_platform_config *pdata;
1309 struct omap2_mcspi *mcspi;
1310 struct resource *r;
1311 int status = 0, i;
1312 u32 regs_offset = 0;
1313 static int bus_num = 1;
1314 struct device_node *node = pdev->dev.of_node;
1315 const struct of_device_id *match;
1316
1317 master = spi_alloc_master(&pdev->dev, sizeof *mcspi);
1318 if (master == NULL) {
1319 dev_dbg(&pdev->dev, "master allocation failed\n");
1320 return -ENOMEM;
1321 }
1322
1323 /* the spi->mode bits understood by this driver: */
1324 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1325 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1326 master->setup = omap2_mcspi_setup;
1327 master->auto_runtime_pm = true;
1328 master->transfer_one = omap2_mcspi_transfer_one;
1329 master->set_cs = omap2_mcspi_set_cs;
1330 master->cleanup = omap2_mcspi_cleanup;
1331 master->dev.of_node = node;
1332 master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1333 master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
1334
1335 platform_set_drvdata(pdev, master);
1336
1337 mcspi = spi_master_get_devdata(master);
1338 mcspi->master = master;
1339
1340 match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1341 if (match) {
1342 u32 num_cs = 1; /* default number of chipselect */
1343 pdata = match->data;
1344
1345 of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1346 master->num_chipselect = num_cs;
1347 master->bus_num = bus_num++;
1348 if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1349 mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1350 } else {
1351 pdata = dev_get_platdata(&pdev->dev);
1352 master->num_chipselect = pdata->num_cs;
1353 if (pdev->id != -1)
1354 master->bus_num = pdev->id;
1355 mcspi->pin_dir = pdata->pin_dir;
1356 }
1357 regs_offset = pdata->regs_offset;
1358
1359 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1360 if (r == NULL) {
1361 status = -ENODEV;
1362 goto free_master;
1363 }
1364
1365 r->start += regs_offset;
1366 r->end += regs_offset;
1367 mcspi->phys = r->start;
1368
1369 mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1370 if (IS_ERR(mcspi->base)) {
1371 status = PTR_ERR(mcspi->base);
1372 goto free_master;
1373 }
1374
1375 mcspi->dev = &pdev->dev;
1376
1377 INIT_LIST_HEAD(&mcspi->ctx.cs);
1378
1379 mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1380 sizeof(struct omap2_mcspi_dma),
1381 GFP_KERNEL);
1382 if (mcspi->dma_channels == NULL) {
1383 status = -ENOMEM;
1384 goto free_master;
1385 }
1386
1387 for (i = 0; i < master->num_chipselect; i++) {
1388 char *dma_rx_ch_name = mcspi->dma_channels[i].dma_rx_ch_name;
1389 char *dma_tx_ch_name = mcspi->dma_channels[i].dma_tx_ch_name;
1390 struct resource *dma_res;
1391
1392 sprintf(dma_rx_ch_name, "rx%d", i);
1393 if (!pdev->dev.of_node) {
1394 dma_res =
1395 platform_get_resource_byname(pdev,
1396 IORESOURCE_DMA,
1397 dma_rx_ch_name);
1398 if (!dma_res) {
1399 dev_dbg(&pdev->dev,
1400 "cannot get DMA RX channel\n");
1401 status = -ENODEV;
1402 break;
1403 }
1404
1405 mcspi->dma_channels[i].dma_rx_sync_dev =
1406 dma_res->start;
1407 }
1408 sprintf(dma_tx_ch_name, "tx%d", i);
1409 if (!pdev->dev.of_node) {
1410 dma_res =
1411 platform_get_resource_byname(pdev,
1412 IORESOURCE_DMA,
1413 dma_tx_ch_name);
1414 if (!dma_res) {
1415 dev_dbg(&pdev->dev,
1416 "cannot get DMA TX channel\n");
1417 status = -ENODEV;
1418 break;
1419 }
1420
1421 mcspi->dma_channels[i].dma_tx_sync_dev =
1422 dma_res->start;
1423 }
1424 }
1425
1426 if (status < 0)
1427 goto free_master;
1428
1429 pm_runtime_use_autosuspend(&pdev->dev);
1430 pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1431 pm_runtime_enable(&pdev->dev);
1432
1433 status = omap2_mcspi_master_setup(mcspi);
1434 if (status < 0)
1435 goto disable_pm;
1436
1437 status = devm_spi_register_master(&pdev->dev, master);
1438 if (status < 0)
1439 goto disable_pm;
1440
1441 return status;
1442
1443 disable_pm:
1444 pm_runtime_disable(&pdev->dev);
1445 free_master:
1446 spi_master_put(master);
1447 return status;
1448 }
1449
1450 static int omap2_mcspi_remove(struct platform_device *pdev)
1451 {
1452 struct spi_master *master = platform_get_drvdata(pdev);
1453 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1454
1455 pm_runtime_put_sync(mcspi->dev);
1456 pm_runtime_disable(&pdev->dev);
1457
1458 return 0;
1459 }
1460
1461 /* work with hotplug and coldplug */
1462 MODULE_ALIAS("platform:omap2_mcspi");
1463
1464 #ifdef CONFIG_SUSPEND
1465 /*
1466 * When SPI wake up from off-mode, CS is in activate state. If it was in
1467 * unactive state when driver was suspend, then force it to unactive state at
1468 * wake up.
1469 */
1470 static int omap2_mcspi_resume(struct device *dev)
1471 {
1472 struct spi_master *master = dev_get_drvdata(dev);
1473 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1474 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1475 struct omap2_mcspi_cs *cs;
1476
1477 pm_runtime_get_sync(mcspi->dev);
1478 list_for_each_entry(cs, &ctx->cs, node) {
1479 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1480 /*
1481 * We need to toggle CS state for OMAP take this
1482 * change in account.
1483 */
1484 cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1485 writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1486 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1487 writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1488 }
1489 }
1490 pm_runtime_mark_last_busy(mcspi->dev);
1491 pm_runtime_put_autosuspend(mcspi->dev);
1492 return 0;
1493 }
1494 #else
1495 #define omap2_mcspi_resume NULL
1496 #endif
1497
1498 static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1499 .resume = omap2_mcspi_resume,
1500 .runtime_resume = omap_mcspi_runtime_resume,
1501 };
1502
1503 static struct platform_driver omap2_mcspi_driver = {
1504 .driver = {
1505 .name = "omap2_mcspi",
1506 .pm = &omap2_mcspi_pm_ops,
1507 .of_match_table = omap_mcspi_of_match,
1508 },
1509 .probe = omap2_mcspi_probe,
1510 .remove = omap2_mcspi_remove,
1511 };
1512
1513 module_platform_driver(omap2_mcspi_driver);
1514 MODULE_LICENSE("GPL");
Linux kernel - Deliverables
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