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Merge branch 'for-4.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj...
[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/pinctrl/consumer.h>
28 #include <linux/platform_device.h>
29 #include <linux/err.h>
30 #include <linux/clk.h>
31 #include <linux/io.h>
32 #include <linux/slab.h>
33 #include <linux/pm_runtime.h>
34 #include <linux/of.h>
35 #include <linux/of_device.h>
36 #include <linux/gcd.h>
37
38 #include <linux/spi/spi.h>
39 #include <linux/gpio.h>
40
41 #include <linux/platform_data/spi-omap2-mcspi.h>
42
43 #define OMAP2_MCSPI_MAX_FREQ 48000000
44 #define OMAP2_MCSPI_MAX_DIVIDER 4096
45 #define OMAP2_MCSPI_MAX_FIFODEPTH 64
46 #define OMAP2_MCSPI_MAX_FIFOWCNT 0xFFFF
47 #define SPI_AUTOSUSPEND_TIMEOUT 2000
48
49 #define OMAP2_MCSPI_REVISION 0x00
50 #define OMAP2_MCSPI_SYSSTATUS 0x14
51 #define OMAP2_MCSPI_IRQSTATUS 0x18
52 #define OMAP2_MCSPI_IRQENABLE 0x1c
53 #define OMAP2_MCSPI_WAKEUPENABLE 0x20
54 #define OMAP2_MCSPI_SYST 0x24
55 #define OMAP2_MCSPI_MODULCTRL 0x28
56 #define OMAP2_MCSPI_XFERLEVEL 0x7c
57
58 /* per-channel banks, 0x14 bytes each, first is: */
59 #define OMAP2_MCSPI_CHCONF0 0x2c
60 #define OMAP2_MCSPI_CHSTAT0 0x30
61 #define OMAP2_MCSPI_CHCTRL0 0x34
62 #define OMAP2_MCSPI_TX0 0x38
63 #define OMAP2_MCSPI_RX0 0x3c
64
65 /* per-register bitmasks: */
66 #define OMAP2_MCSPI_IRQSTATUS_EOW BIT(17)
67
68 #define OMAP2_MCSPI_MODULCTRL_SINGLE BIT(0)
69 #define OMAP2_MCSPI_MODULCTRL_MS BIT(2)
70 #define OMAP2_MCSPI_MODULCTRL_STEST BIT(3)
71
72 #define OMAP2_MCSPI_CHCONF_PHA BIT(0)
73 #define OMAP2_MCSPI_CHCONF_POL BIT(1)
74 #define OMAP2_MCSPI_CHCONF_CLKD_MASK (0x0f << 2)
75 #define OMAP2_MCSPI_CHCONF_EPOL BIT(6)
76 #define OMAP2_MCSPI_CHCONF_WL_MASK (0x1f << 7)
77 #define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY BIT(12)
78 #define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY BIT(13)
79 #define OMAP2_MCSPI_CHCONF_TRM_MASK (0x03 << 12)
80 #define OMAP2_MCSPI_CHCONF_DMAW BIT(14)
81 #define OMAP2_MCSPI_CHCONF_DMAR BIT(15)
82 #define OMAP2_MCSPI_CHCONF_DPE0 BIT(16)
83 #define OMAP2_MCSPI_CHCONF_DPE1 BIT(17)
84 #define OMAP2_MCSPI_CHCONF_IS BIT(18)
85 #define OMAP2_MCSPI_CHCONF_TURBO BIT(19)
86 #define OMAP2_MCSPI_CHCONF_FORCE BIT(20)
87 #define OMAP2_MCSPI_CHCONF_FFET BIT(27)
88 #define OMAP2_MCSPI_CHCONF_FFER BIT(28)
89 #define OMAP2_MCSPI_CHCONF_CLKG BIT(29)
90
91 #define OMAP2_MCSPI_CHSTAT_RXS BIT(0)
92 #define OMAP2_MCSPI_CHSTAT_TXS BIT(1)
93 #define OMAP2_MCSPI_CHSTAT_EOT BIT(2)
94 #define OMAP2_MCSPI_CHSTAT_TXFFE BIT(3)
95
96 #define OMAP2_MCSPI_CHCTRL_EN BIT(0)
97 #define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK (0xff << 8)
98
99 #define OMAP2_MCSPI_WAKEUPENABLE_WKEN BIT(0)
100
101 /* We have 2 DMA channels per CS, one for RX and one for TX */
102 struct omap2_mcspi_dma {
103 struct dma_chan *dma_tx;
104 struct dma_chan *dma_rx;
105
106 int dma_tx_sync_dev;
107 int dma_rx_sync_dev;
108
109 struct completion dma_tx_completion;
110 struct completion dma_rx_completion;
111
112 char dma_rx_ch_name[14];
113 char dma_tx_ch_name[14];
114 };
115
116 /* use PIO for small transfers, avoiding DMA setup/teardown overhead and
117 * cache operations; better heuristics consider wordsize and bitrate.
118 */
119 #define DMA_MIN_BYTES 160
120
121
122 /*
123 * Used for context save and restore, structure members to be updated whenever
124 * corresponding registers are modified.
125 */
126 struct omap2_mcspi_regs {
127 u32 modulctrl;
128 u32 wakeupenable;
129 struct list_head cs;
130 };
131
132 struct omap2_mcspi {
133 struct spi_master *master;
134 /* Virtual base address of the controller */
135 void __iomem *base;
136 unsigned long phys;
137 /* SPI1 has 4 channels, while SPI2 has 2 */
138 struct omap2_mcspi_dma *dma_channels;
139 struct device *dev;
140 struct omap2_mcspi_regs ctx;
141 int fifo_depth;
142 unsigned int pin_dir:1;
143 };
144
145 struct omap2_mcspi_cs {
146 void __iomem *base;
147 unsigned long phys;
148 int word_len;
149 u16 mode;
150 struct list_head node;
151 /* Context save and restore shadow register */
152 u32 chconf0, chctrl0;
153 };
154
155 static inline void mcspi_write_reg(struct spi_master *master,
156 int idx, u32 val)
157 {
158 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
159
160 writel_relaxed(val, mcspi->base + idx);
161 }
162
163 static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
164 {
165 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
166
167 return readl_relaxed(mcspi->base + idx);
168 }
169
170 static inline void mcspi_write_cs_reg(const struct spi_device *spi,
171 int idx, u32 val)
172 {
173 struct omap2_mcspi_cs *cs = spi->controller_state;
174
175 writel_relaxed(val, cs->base + idx);
176 }
177
178 static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
179 {
180 struct omap2_mcspi_cs *cs = spi->controller_state;
181
182 return readl_relaxed(cs->base + idx);
183 }
184
185 static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
186 {
187 struct omap2_mcspi_cs *cs = spi->controller_state;
188
189 return cs->chconf0;
190 }
191
192 static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
193 {
194 struct omap2_mcspi_cs *cs = spi->controller_state;
195
196 cs->chconf0 = val;
197 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
198 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
199 }
200
201 static inline int mcspi_bytes_per_word(int word_len)
202 {
203 if (word_len <= 8)
204 return 1;
205 else if (word_len <= 16)
206 return 2;
207 else /* word_len <= 32 */
208 return 4;
209 }
210
211 static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
212 int is_read, int enable)
213 {
214 u32 l, rw;
215
216 l = mcspi_cached_chconf0(spi);
217
218 if (is_read) /* 1 is read, 0 write */
219 rw = OMAP2_MCSPI_CHCONF_DMAR;
220 else
221 rw = OMAP2_MCSPI_CHCONF_DMAW;
222
223 if (enable)
224 l |= rw;
225 else
226 l &= ~rw;
227
228 mcspi_write_chconf0(spi, l);
229 }
230
231 static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
232 {
233 struct omap2_mcspi_cs *cs = spi->controller_state;
234 u32 l;
235
236 l = cs->chctrl0;
237 if (enable)
238 l |= OMAP2_MCSPI_CHCTRL_EN;
239 else
240 l &= ~OMAP2_MCSPI_CHCTRL_EN;
241 cs->chctrl0 = l;
242 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
243 /* Flash post-writes */
244 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
245 }
246
247 static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable)
248 {
249 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
250 u32 l;
251
252 /* The controller handles the inverted chip selects
253 * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert
254 * the inversion from the core spi_set_cs function.
255 */
256 if (spi->mode & SPI_CS_HIGH)
257 enable = !enable;
258
259 if (spi->controller_state) {
260 int err = pm_runtime_get_sync(mcspi->dev);
261 if (err < 0) {
262 dev_err(mcspi->dev, "failed to get sync: %d\n", err);
263 return;
264 }
265
266 l = mcspi_cached_chconf0(spi);
267
268 if (enable)
269 l &= ~OMAP2_MCSPI_CHCONF_FORCE;
270 else
271 l |= OMAP2_MCSPI_CHCONF_FORCE;
272
273 mcspi_write_chconf0(spi, l);
274
275 pm_runtime_mark_last_busy(mcspi->dev);
276 pm_runtime_put_autosuspend(mcspi->dev);
277 }
278 }
279
280 static void omap2_mcspi_set_master_mode(struct spi_master *master)
281 {
282 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
283 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
284 u32 l;
285
286 /*
287 * Setup when switching from (reset default) slave mode
288 * to single-channel master mode
289 */
290 l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
291 l &= ~(OMAP2_MCSPI_MODULCTRL_STEST | OMAP2_MCSPI_MODULCTRL_MS);
292 l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
293 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
294
295 ctx->modulctrl = l;
296 }
297
298 static void omap2_mcspi_set_fifo(const struct spi_device *spi,
299 struct spi_transfer *t, int enable)
300 {
301 struct spi_master *master = spi->master;
302 struct omap2_mcspi_cs *cs = spi->controller_state;
303 struct omap2_mcspi *mcspi;
304 unsigned int wcnt;
305 int max_fifo_depth, fifo_depth, bytes_per_word;
306 u32 chconf, xferlevel;
307
308 mcspi = spi_master_get_devdata(master);
309
310 chconf = mcspi_cached_chconf0(spi);
311 if (enable) {
312 bytes_per_word = mcspi_bytes_per_word(cs->word_len);
313 if (t->len % bytes_per_word != 0)
314 goto disable_fifo;
315
316 if (t->rx_buf != NULL && t->tx_buf != NULL)
317 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
318 else
319 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
320
321 fifo_depth = gcd(t->len, max_fifo_depth);
322 if (fifo_depth < 2 || fifo_depth % bytes_per_word != 0)
323 goto disable_fifo;
324
325 wcnt = t->len / bytes_per_word;
326 if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
327 goto disable_fifo;
328
329 xferlevel = wcnt << 16;
330 if (t->rx_buf != NULL) {
331 chconf |= OMAP2_MCSPI_CHCONF_FFER;
332 xferlevel |= (fifo_depth - 1) << 8;
333 }
334 if (t->tx_buf != NULL) {
335 chconf |= OMAP2_MCSPI_CHCONF_FFET;
336 xferlevel |= fifo_depth - 1;
337 }
338
339 mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel);
340 mcspi_write_chconf0(spi, chconf);
341 mcspi->fifo_depth = fifo_depth;
342
343 return;
344 }
345
346 disable_fifo:
347 if (t->rx_buf != NULL)
348 chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
349
350 if (t->tx_buf != NULL)
351 chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
352
353 mcspi_write_chconf0(spi, chconf);
354 mcspi->fifo_depth = 0;
355 }
356
357 static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
358 {
359 struct spi_master *spi_cntrl = mcspi->master;
360 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
361 struct omap2_mcspi_cs *cs;
362
363 /* McSPI: context restore */
364 mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
365 mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
366
367 list_for_each_entry(cs, &ctx->cs, node)
368 writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
369 }
370
371 static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
372 {
373 unsigned long timeout;
374
375 timeout = jiffies + msecs_to_jiffies(1000);
376 while (!(readl_relaxed(reg) & bit)) {
377 if (time_after(jiffies, timeout)) {
378 if (!(readl_relaxed(reg) & bit))
379 return -ETIMEDOUT;
380 else
381 return 0;
382 }
383 cpu_relax();
384 }
385 return 0;
386 }
387
388 static void omap2_mcspi_rx_callback(void *data)
389 {
390 struct spi_device *spi = data;
391 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
392 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
393
394 /* We must disable the DMA RX request */
395 omap2_mcspi_set_dma_req(spi, 1, 0);
396
397 complete(&mcspi_dma->dma_rx_completion);
398 }
399
400 static void omap2_mcspi_tx_callback(void *data)
401 {
402 struct spi_device *spi = data;
403 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
404 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
405
406 /* We must disable the DMA TX request */
407 omap2_mcspi_set_dma_req(spi, 0, 0);
408
409 complete(&mcspi_dma->dma_tx_completion);
410 }
411
412 static void omap2_mcspi_tx_dma(struct spi_device *spi,
413 struct spi_transfer *xfer,
414 struct dma_slave_config cfg)
415 {
416 struct omap2_mcspi *mcspi;
417 struct omap2_mcspi_dma *mcspi_dma;
418 unsigned int count;
419
420 mcspi = spi_master_get_devdata(spi->master);
421 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
422 count = xfer->len;
423
424 if (mcspi_dma->dma_tx) {
425 struct dma_async_tx_descriptor *tx;
426
427 dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
428
429 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, xfer->tx_sg.sgl,
430 xfer->tx_sg.nents, DMA_MEM_TO_DEV,
431 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
432 if (tx) {
433 tx->callback = omap2_mcspi_tx_callback;
434 tx->callback_param = spi;
435 dmaengine_submit(tx);
436 } else {
437 /* FIXME: fall back to PIO? */
438 }
439 }
440 dma_async_issue_pending(mcspi_dma->dma_tx);
441 omap2_mcspi_set_dma_req(spi, 0, 1);
442
443 }
444
445 static unsigned
446 omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
447 struct dma_slave_config cfg,
448 unsigned es)
449 {
450 struct omap2_mcspi *mcspi;
451 struct omap2_mcspi_dma *mcspi_dma;
452 unsigned int count, dma_count;
453 u32 l;
454 int elements = 0;
455 int word_len, element_count;
456 struct omap2_mcspi_cs *cs = spi->controller_state;
457 mcspi = spi_master_get_devdata(spi->master);
458 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
459 count = xfer->len;
460 dma_count = xfer->len;
461
462 if (mcspi->fifo_depth == 0)
463 dma_count -= es;
464
465 word_len = cs->word_len;
466 l = mcspi_cached_chconf0(spi);
467
468 if (word_len <= 8)
469 element_count = count;
470 else if (word_len <= 16)
471 element_count = count >> 1;
472 else /* word_len <= 32 */
473 element_count = count >> 2;
474
475 if (mcspi_dma->dma_rx) {
476 struct dma_async_tx_descriptor *tx;
477
478 dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
479
480 if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
481 dma_count -= es;
482
483 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, xfer->rx_sg.sgl,
484 xfer->rx_sg.nents, DMA_DEV_TO_MEM,
485 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
486 if (tx) {
487 tx->callback = omap2_mcspi_rx_callback;
488 tx->callback_param = spi;
489 dmaengine_submit(tx);
490 } else {
491 /* FIXME: fall back to PIO? */
492 }
493 }
494
495 dma_async_issue_pending(mcspi_dma->dma_rx);
496 omap2_mcspi_set_dma_req(spi, 1, 1);
497
498 wait_for_completion(&mcspi_dma->dma_rx_completion);
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
612 if (mcspi->fifo_depth > 0) {
613 irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
614
615 if (mcspi_wait_for_reg_bit(irqstat_reg,
616 OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
617 dev_err(&spi->dev, "EOW timed out\n");
618
619 mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
620 OMAP2_MCSPI_IRQSTATUS_EOW);
621 }
622
623 /* for TX_ONLY mode, be sure all words have shifted out */
624 if (rx == NULL) {
625 chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
626 if (mcspi->fifo_depth > 0) {
627 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
628 OMAP2_MCSPI_CHSTAT_TXFFE);
629 if (wait_res < 0)
630 dev_err(&spi->dev, "TXFFE timed out\n");
631 } else {
632 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
633 OMAP2_MCSPI_CHSTAT_TXS);
634 if (wait_res < 0)
635 dev_err(&spi->dev, "TXS timed out\n");
636 }
637 if (wait_res >= 0 &&
638 (mcspi_wait_for_reg_bit(chstat_reg,
639 OMAP2_MCSPI_CHSTAT_EOT) < 0))
640 dev_err(&spi->dev, "EOT timed out\n");
641 }
642 }
643 return count;
644 }
645
646 static unsigned
647 omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
648 {
649 struct omap2_mcspi *mcspi;
650 struct omap2_mcspi_cs *cs = spi->controller_state;
651 unsigned int count, c;
652 u32 l;
653 void __iomem *base = cs->base;
654 void __iomem *tx_reg;
655 void __iomem *rx_reg;
656 void __iomem *chstat_reg;
657 int word_len;
658
659 mcspi = spi_master_get_devdata(spi->master);
660 count = xfer->len;
661 c = count;
662 word_len = cs->word_len;
663
664 l = mcspi_cached_chconf0(spi);
665
666 /* We store the pre-calculated register addresses on stack to speed
667 * up the transfer loop. */
668 tx_reg = base + OMAP2_MCSPI_TX0;
669 rx_reg = base + OMAP2_MCSPI_RX0;
670 chstat_reg = base + OMAP2_MCSPI_CHSTAT0;
671
672 if (c < (word_len>>3))
673 return 0;
674
675 if (word_len <= 8) {
676 u8 *rx;
677 const u8 *tx;
678
679 rx = xfer->rx_buf;
680 tx = xfer->tx_buf;
681
682 do {
683 c -= 1;
684 if (tx != NULL) {
685 if (mcspi_wait_for_reg_bit(chstat_reg,
686 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
687 dev_err(&spi->dev, "TXS timed out\n");
688 goto out;
689 }
690 dev_vdbg(&spi->dev, "write-%d %02x\n",
691 word_len, *tx);
692 writel_relaxed(*tx++, tx_reg);
693 }
694 if (rx != NULL) {
695 if (mcspi_wait_for_reg_bit(chstat_reg,
696 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
697 dev_err(&spi->dev, "RXS timed out\n");
698 goto out;
699 }
700
701 if (c == 1 && tx == NULL &&
702 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
703 omap2_mcspi_set_enable(spi, 0);
704 *rx++ = readl_relaxed(rx_reg);
705 dev_vdbg(&spi->dev, "read-%d %02x\n",
706 word_len, *(rx - 1));
707 if (mcspi_wait_for_reg_bit(chstat_reg,
708 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
709 dev_err(&spi->dev,
710 "RXS timed out\n");
711 goto out;
712 }
713 c = 0;
714 } else if (c == 0 && tx == NULL) {
715 omap2_mcspi_set_enable(spi, 0);
716 }
717
718 *rx++ = readl_relaxed(rx_reg);
719 dev_vdbg(&spi->dev, "read-%d %02x\n",
720 word_len, *(rx - 1));
721 }
722 } while (c);
723 } else if (word_len <= 16) {
724 u16 *rx;
725 const u16 *tx;
726
727 rx = xfer->rx_buf;
728 tx = xfer->tx_buf;
729 do {
730 c -= 2;
731 if (tx != NULL) {
732 if (mcspi_wait_for_reg_bit(chstat_reg,
733 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
734 dev_err(&spi->dev, "TXS timed out\n");
735 goto out;
736 }
737 dev_vdbg(&spi->dev, "write-%d %04x\n",
738 word_len, *tx);
739 writel_relaxed(*tx++, tx_reg);
740 }
741 if (rx != NULL) {
742 if (mcspi_wait_for_reg_bit(chstat_reg,
743 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
744 dev_err(&spi->dev, "RXS timed out\n");
745 goto out;
746 }
747
748 if (c == 2 && tx == NULL &&
749 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
750 omap2_mcspi_set_enable(spi, 0);
751 *rx++ = readl_relaxed(rx_reg);
752 dev_vdbg(&spi->dev, "read-%d %04x\n",
753 word_len, *(rx - 1));
754 if (mcspi_wait_for_reg_bit(chstat_reg,
755 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
756 dev_err(&spi->dev,
757 "RXS timed out\n");
758 goto out;
759 }
760 c = 0;
761 } else if (c == 0 && tx == NULL) {
762 omap2_mcspi_set_enable(spi, 0);
763 }
764
765 *rx++ = readl_relaxed(rx_reg);
766 dev_vdbg(&spi->dev, "read-%d %04x\n",
767 word_len, *(rx - 1));
768 }
769 } while (c >= 2);
770 } else if (word_len <= 32) {
771 u32 *rx;
772 const u32 *tx;
773
774 rx = xfer->rx_buf;
775 tx = xfer->tx_buf;
776 do {
777 c -= 4;
778 if (tx != NULL) {
779 if (mcspi_wait_for_reg_bit(chstat_reg,
780 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
781 dev_err(&spi->dev, "TXS timed out\n");
782 goto out;
783 }
784 dev_vdbg(&spi->dev, "write-%d %08x\n",
785 word_len, *tx);
786 writel_relaxed(*tx++, tx_reg);
787 }
788 if (rx != NULL) {
789 if (mcspi_wait_for_reg_bit(chstat_reg,
790 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
791 dev_err(&spi->dev, "RXS timed out\n");
792 goto out;
793 }
794
795 if (c == 4 && tx == NULL &&
796 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
797 omap2_mcspi_set_enable(spi, 0);
798 *rx++ = readl_relaxed(rx_reg);
799 dev_vdbg(&spi->dev, "read-%d %08x\n",
800 word_len, *(rx - 1));
801 if (mcspi_wait_for_reg_bit(chstat_reg,
802 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
803 dev_err(&spi->dev,
804 "RXS timed out\n");
805 goto out;
806 }
807 c = 0;
808 } else if (c == 0 && tx == NULL) {
809 omap2_mcspi_set_enable(spi, 0);
810 }
811
812 *rx++ = readl_relaxed(rx_reg);
813 dev_vdbg(&spi->dev, "read-%d %08x\n",
814 word_len, *(rx - 1));
815 }
816 } while (c >= 4);
817 }
818
819 /* for TX_ONLY mode, be sure all words have shifted out */
820 if (xfer->rx_buf == NULL) {
821 if (mcspi_wait_for_reg_bit(chstat_reg,
822 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
823 dev_err(&spi->dev, "TXS timed out\n");
824 } else if (mcspi_wait_for_reg_bit(chstat_reg,
825 OMAP2_MCSPI_CHSTAT_EOT) < 0)
826 dev_err(&spi->dev, "EOT timed out\n");
827
828 /* disable chan to purge rx datas received in TX_ONLY transfer,
829 * otherwise these rx datas will affect the direct following
830 * RX_ONLY transfer.
831 */
832 omap2_mcspi_set_enable(spi, 0);
833 }
834 out:
835 omap2_mcspi_set_enable(spi, 1);
836 return count - c;
837 }
838
839 static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
840 {
841 u32 div;
842
843 for (div = 0; div < 15; div++)
844 if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
845 return div;
846
847 return 15;
848 }
849
850 /* called only when no transfer is active to this device */
851 static int omap2_mcspi_setup_transfer(struct spi_device *spi,
852 struct spi_transfer *t)
853 {
854 struct omap2_mcspi_cs *cs = spi->controller_state;
855 struct omap2_mcspi *mcspi;
856 struct spi_master *spi_cntrl;
857 u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
858 u8 word_len = spi->bits_per_word;
859 u32 speed_hz = spi->max_speed_hz;
860
861 mcspi = spi_master_get_devdata(spi->master);
862 spi_cntrl = mcspi->master;
863
864 if (t != NULL && t->bits_per_word)
865 word_len = t->bits_per_word;
866
867 cs->word_len = word_len;
868
869 if (t && t->speed_hz)
870 speed_hz = t->speed_hz;
871
872 speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
873 if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
874 clkd = omap2_mcspi_calc_divisor(speed_hz);
875 speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
876 clkg = 0;
877 } else {
878 div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
879 speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
880 clkd = (div - 1) & 0xf;
881 extclk = (div - 1) >> 4;
882 clkg = OMAP2_MCSPI_CHCONF_CLKG;
883 }
884
885 l = mcspi_cached_chconf0(spi);
886
887 /* standard 4-wire master mode: SCK, MOSI/out, MISO/in, nCS
888 * REVISIT: this controller could support SPI_3WIRE mode.
889 */
890 if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
891 l &= ~OMAP2_MCSPI_CHCONF_IS;
892 l &= ~OMAP2_MCSPI_CHCONF_DPE1;
893 l |= OMAP2_MCSPI_CHCONF_DPE0;
894 } else {
895 l |= OMAP2_MCSPI_CHCONF_IS;
896 l |= OMAP2_MCSPI_CHCONF_DPE1;
897 l &= ~OMAP2_MCSPI_CHCONF_DPE0;
898 }
899
900 /* wordlength */
901 l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
902 l |= (word_len - 1) << 7;
903
904 /* set chipselect polarity; manage with FORCE */
905 if (!(spi->mode & SPI_CS_HIGH))
906 l |= OMAP2_MCSPI_CHCONF_EPOL; /* active-low; normal */
907 else
908 l &= ~OMAP2_MCSPI_CHCONF_EPOL;
909
910 /* set clock divisor */
911 l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
912 l |= clkd << 2;
913
914 /* set clock granularity */
915 l &= ~OMAP2_MCSPI_CHCONF_CLKG;
916 l |= clkg;
917 if (clkg) {
918 cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
919 cs->chctrl0 |= extclk << 8;
920 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
921 }
922
923 /* set SPI mode 0..3 */
924 if (spi->mode & SPI_CPOL)
925 l |= OMAP2_MCSPI_CHCONF_POL;
926 else
927 l &= ~OMAP2_MCSPI_CHCONF_POL;
928 if (spi->mode & SPI_CPHA)
929 l |= OMAP2_MCSPI_CHCONF_PHA;
930 else
931 l &= ~OMAP2_MCSPI_CHCONF_PHA;
932
933 mcspi_write_chconf0(spi, l);
934
935 cs->mode = spi->mode;
936
937 dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
938 speed_hz,
939 (spi->mode & SPI_CPHA) ? "trailing" : "leading",
940 (spi->mode & SPI_CPOL) ? "inverted" : "normal");
941
942 return 0;
943 }
944
945 /*
946 * Note that we currently allow DMA only if we get a channel
947 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
948 */
949 static int omap2_mcspi_request_dma(struct spi_device *spi)
950 {
951 struct spi_master *master = spi->master;
952 struct omap2_mcspi *mcspi;
953 struct omap2_mcspi_dma *mcspi_dma;
954 dma_cap_mask_t mask;
955 unsigned sig;
956
957 mcspi = spi_master_get_devdata(master);
958 mcspi_dma = mcspi->dma_channels + spi->chip_select;
959
960 init_completion(&mcspi_dma->dma_rx_completion);
961 init_completion(&mcspi_dma->dma_tx_completion);
962
963 dma_cap_zero(mask);
964 dma_cap_set(DMA_SLAVE, mask);
965 sig = mcspi_dma->dma_rx_sync_dev;
966
967 mcspi_dma->dma_rx =
968 dma_request_slave_channel_compat(mask, omap_dma_filter_fn,
969 &sig, &master->dev,
970 mcspi_dma->dma_rx_ch_name);
971 if (!mcspi_dma->dma_rx)
972 goto no_dma;
973
974 sig = mcspi_dma->dma_tx_sync_dev;
975 mcspi_dma->dma_tx =
976 dma_request_slave_channel_compat(mask, omap_dma_filter_fn,
977 &sig, &master->dev,
978 mcspi_dma->dma_tx_ch_name);
979
980 if (!mcspi_dma->dma_tx) {
981 dma_release_channel(mcspi_dma->dma_rx);
982 mcspi_dma->dma_rx = NULL;
983 goto no_dma;
984 }
985
986 return 0;
987
988 no_dma:
989 dev_warn(&spi->dev, "not using DMA for McSPI\n");
990 return -EAGAIN;
991 }
992
993 static int omap2_mcspi_setup(struct spi_device *spi)
994 {
995 int ret;
996 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
997 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
998 struct omap2_mcspi_dma *mcspi_dma;
999 struct omap2_mcspi_cs *cs = spi->controller_state;
1000
1001 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1002
1003 if (!cs) {
1004 cs = kzalloc(sizeof *cs, GFP_KERNEL);
1005 if (!cs)
1006 return -ENOMEM;
1007 cs->base = mcspi->base + spi->chip_select * 0x14;
1008 cs->phys = mcspi->phys + spi->chip_select * 0x14;
1009 cs->mode = 0;
1010 cs->chconf0 = 0;
1011 cs->chctrl0 = 0;
1012 spi->controller_state = cs;
1013 /* Link this to context save list */
1014 list_add_tail(&cs->node, &ctx->cs);
1015
1016 if (gpio_is_valid(spi->cs_gpio)) {
1017 ret = gpio_request(spi->cs_gpio, dev_name(&spi->dev));
1018 if (ret) {
1019 dev_err(&spi->dev, "failed to request gpio\n");
1020 return ret;
1021 }
1022 gpio_direction_output(spi->cs_gpio,
1023 !(spi->mode & SPI_CS_HIGH));
1024 }
1025 }
1026
1027 if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) {
1028 ret = omap2_mcspi_request_dma(spi);
1029 if (ret < 0 && ret != -EAGAIN)
1030 return ret;
1031 }
1032
1033 ret = pm_runtime_get_sync(mcspi->dev);
1034 if (ret < 0)
1035 return ret;
1036
1037 ret = omap2_mcspi_setup_transfer(spi, NULL);
1038 pm_runtime_mark_last_busy(mcspi->dev);
1039 pm_runtime_put_autosuspend(mcspi->dev);
1040
1041 return ret;
1042 }
1043
1044 static void omap2_mcspi_cleanup(struct spi_device *spi)
1045 {
1046 struct omap2_mcspi *mcspi;
1047 struct omap2_mcspi_dma *mcspi_dma;
1048 struct omap2_mcspi_cs *cs;
1049
1050 mcspi = spi_master_get_devdata(spi->master);
1051
1052 if (spi->controller_state) {
1053 /* Unlink controller state from context save list */
1054 cs = spi->controller_state;
1055 list_del(&cs->node);
1056
1057 kfree(cs);
1058 }
1059
1060 if (spi->chip_select < spi->master->num_chipselect) {
1061 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1062
1063 if (mcspi_dma->dma_rx) {
1064 dma_release_channel(mcspi_dma->dma_rx);
1065 mcspi_dma->dma_rx = NULL;
1066 }
1067 if (mcspi_dma->dma_tx) {
1068 dma_release_channel(mcspi_dma->dma_tx);
1069 mcspi_dma->dma_tx = NULL;
1070 }
1071 }
1072
1073 if (gpio_is_valid(spi->cs_gpio))
1074 gpio_free(spi->cs_gpio);
1075 }
1076
1077 static bool omap2_mcspi_can_dma(struct spi_master *master,
1078 struct spi_device *spi,
1079 struct spi_transfer *xfer)
1080 {
1081 if (xfer->len < DMA_MIN_BYTES)
1082 return false;
1083
1084 return true;
1085 }
1086
1087 static int omap2_mcspi_work_one(struct omap2_mcspi *mcspi,
1088 struct spi_device *spi, struct spi_transfer *t)
1089 {
1090
1091 /* We only enable one channel at a time -- the one whose message is
1092 * -- although this controller would gladly
1093 * arbitrate among multiple channels. This corresponds to "single
1094 * channel" master mode. As a side effect, we need to manage the
1095 * chipselect with the FORCE bit ... CS != channel enable.
1096 */
1097
1098 struct spi_master *master;
1099 struct omap2_mcspi_dma *mcspi_dma;
1100 struct omap2_mcspi_cs *cs;
1101 struct omap2_mcspi_device_config *cd;
1102 int par_override = 0;
1103 int status = 0;
1104 u32 chconf;
1105
1106 master = spi->master;
1107 mcspi_dma = mcspi->dma_channels + spi->chip_select;
1108 cs = spi->controller_state;
1109 cd = spi->controller_data;
1110
1111 /*
1112 * The slave driver could have changed spi->mode in which case
1113 * it will be different from cs->mode (the current hardware setup).
1114 * If so, set par_override (even though its not a parity issue) so
1115 * omap2_mcspi_setup_transfer will be called to configure the hardware
1116 * with the correct mode on the first iteration of the loop below.
1117 */
1118 if (spi->mode != cs->mode)
1119 par_override = 1;
1120
1121 omap2_mcspi_set_enable(spi, 0);
1122
1123 if (gpio_is_valid(spi->cs_gpio))
1124 omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH);
1125
1126 if (par_override ||
1127 (t->speed_hz != spi->max_speed_hz) ||
1128 (t->bits_per_word != spi->bits_per_word)) {
1129 par_override = 1;
1130 status = omap2_mcspi_setup_transfer(spi, t);
1131 if (status < 0)
1132 goto out;
1133 if (t->speed_hz == spi->max_speed_hz &&
1134 t->bits_per_word == spi->bits_per_word)
1135 par_override = 0;
1136 }
1137 if (cd && cd->cs_per_word) {
1138 chconf = mcspi->ctx.modulctrl;
1139 chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1140 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1141 mcspi->ctx.modulctrl =
1142 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1143 }
1144
1145 chconf = mcspi_cached_chconf0(spi);
1146 chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1147 chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
1148
1149 if (t->tx_buf == NULL)
1150 chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1151 else if (t->rx_buf == NULL)
1152 chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1153
1154 if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1155 /* Turbo mode is for more than one word */
1156 if (t->len > ((cs->word_len + 7) >> 3))
1157 chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1158 }
1159
1160 mcspi_write_chconf0(spi, chconf);
1161
1162 if (t->len) {
1163 unsigned count;
1164
1165 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1166 (t->len >= DMA_MIN_BYTES))
1167 omap2_mcspi_set_fifo(spi, t, 1);
1168
1169 omap2_mcspi_set_enable(spi, 1);
1170
1171 /* RX_ONLY mode needs dummy data in TX reg */
1172 if (t->tx_buf == NULL)
1173 writel_relaxed(0, cs->base
1174 + OMAP2_MCSPI_TX0);
1175
1176 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1177 (t->len >= DMA_MIN_BYTES))
1178 count = omap2_mcspi_txrx_dma(spi, t);
1179 else
1180 count = omap2_mcspi_txrx_pio(spi, t);
1181
1182 if (count != t->len) {
1183 status = -EIO;
1184 goto out;
1185 }
1186 }
1187
1188 omap2_mcspi_set_enable(spi, 0);
1189
1190 if (mcspi->fifo_depth > 0)
1191 omap2_mcspi_set_fifo(spi, t, 0);
1192
1193 out:
1194 /* Restore defaults if they were overriden */
1195 if (par_override) {
1196 par_override = 0;
1197 status = omap2_mcspi_setup_transfer(spi, NULL);
1198 }
1199
1200 if (cd && cd->cs_per_word) {
1201 chconf = mcspi->ctx.modulctrl;
1202 chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1203 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1204 mcspi->ctx.modulctrl =
1205 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1206 }
1207
1208 omap2_mcspi_set_enable(spi, 0);
1209
1210 if (gpio_is_valid(spi->cs_gpio))
1211 omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
1212
1213 if (mcspi->fifo_depth > 0 && t)
1214 omap2_mcspi_set_fifo(spi, t, 0);
1215
1216 return status;
1217 }
1218
1219 static int omap2_mcspi_prepare_message(struct spi_master *master,
1220 struct spi_message *msg)
1221 {
1222 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1223 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1224 struct omap2_mcspi_cs *cs;
1225
1226 /* Only a single channel can have the FORCE bit enabled
1227 * in its chconf0 register.
1228 * Scan all channels and disable them except the current one.
1229 * A FORCE can remain from a last transfer having cs_change enabled
1230 */
1231 list_for_each_entry(cs, &ctx->cs, node) {
1232 if (msg->spi->controller_state == cs)
1233 continue;
1234
1235 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
1236 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1237 writel_relaxed(cs->chconf0,
1238 cs->base + OMAP2_MCSPI_CHCONF0);
1239 readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
1240 }
1241 }
1242
1243 return 0;
1244 }
1245
1246 static int omap2_mcspi_transfer_one(struct spi_master *master,
1247 struct spi_device *spi, struct spi_transfer *t)
1248 {
1249 struct omap2_mcspi *mcspi;
1250 struct omap2_mcspi_dma *mcspi_dma;
1251 const void *tx_buf = t->tx_buf;
1252 void *rx_buf = t->rx_buf;
1253 unsigned len = t->len;
1254
1255 mcspi = spi_master_get_devdata(master);
1256 mcspi_dma = mcspi->dma_channels + spi->chip_select;
1257
1258 if ((len && !(rx_buf || tx_buf))) {
1259 dev_dbg(mcspi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
1260 t->speed_hz,
1261 len,
1262 tx_buf ? "tx" : "",
1263 rx_buf ? "rx" : "",
1264 t->bits_per_word);
1265 return -EINVAL;
1266 }
1267
1268 return omap2_mcspi_work_one(mcspi, spi, t);
1269 }
1270
1271 static int omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
1272 {
1273 struct spi_master *master = mcspi->master;
1274 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1275 int ret = 0;
1276
1277 ret = pm_runtime_get_sync(mcspi->dev);
1278 if (ret < 0)
1279 return ret;
1280
1281 mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1282 OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1283 ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1284
1285 omap2_mcspi_set_master_mode(master);
1286 pm_runtime_mark_last_busy(mcspi->dev);
1287 pm_runtime_put_autosuspend(mcspi->dev);
1288 return 0;
1289 }
1290
1291 static int omap_mcspi_runtime_resume(struct device *dev)
1292 {
1293 struct omap2_mcspi *mcspi;
1294 struct spi_master *master;
1295
1296 master = dev_get_drvdata(dev);
1297 mcspi = spi_master_get_devdata(master);
1298 omap2_mcspi_restore_ctx(mcspi);
1299
1300 return 0;
1301 }
1302
1303 static struct omap2_mcspi_platform_config omap2_pdata = {
1304 .regs_offset = 0,
1305 };
1306
1307 static struct omap2_mcspi_platform_config omap4_pdata = {
1308 .regs_offset = OMAP4_MCSPI_REG_OFFSET,
1309 };
1310
1311 static const struct of_device_id omap_mcspi_of_match[] = {
1312 {
1313 .compatible = "ti,omap2-mcspi",
1314 .data = &omap2_pdata,
1315 },
1316 {
1317 .compatible = "ti,omap4-mcspi",
1318 .data = &omap4_pdata,
1319 },
1320 { },
1321 };
1322 MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1323
1324 static int omap2_mcspi_probe(struct platform_device *pdev)
1325 {
1326 struct spi_master *master;
1327 const struct omap2_mcspi_platform_config *pdata;
1328 struct omap2_mcspi *mcspi;
1329 struct resource *r;
1330 int status = 0, i;
1331 u32 regs_offset = 0;
1332 static int bus_num = 1;
1333 struct device_node *node = pdev->dev.of_node;
1334 const struct of_device_id *match;
1335
1336 master = spi_alloc_master(&pdev->dev, sizeof *mcspi);
1337 if (master == NULL) {
1338 dev_dbg(&pdev->dev, "master allocation failed\n");
1339 return -ENOMEM;
1340 }
1341
1342 /* the spi->mode bits understood by this driver: */
1343 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1344 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1345 master->setup = omap2_mcspi_setup;
1346 master->auto_runtime_pm = true;
1347 master->prepare_message = omap2_mcspi_prepare_message;
1348 master->transfer_one = omap2_mcspi_transfer_one;
1349 master->set_cs = omap2_mcspi_set_cs;
1350 master->cleanup = omap2_mcspi_cleanup;
1351 master->can_dma = omap2_mcspi_can_dma;
1352 master->dev.of_node = node;
1353 master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1354 master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
1355
1356 platform_set_drvdata(pdev, master);
1357
1358 mcspi = spi_master_get_devdata(master);
1359 mcspi->master = master;
1360
1361 match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1362 if (match) {
1363 u32 num_cs = 1; /* default number of chipselect */
1364 pdata = match->data;
1365
1366 of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1367 master->num_chipselect = num_cs;
1368 master->bus_num = bus_num++;
1369 if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1370 mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1371 } else {
1372 pdata = dev_get_platdata(&pdev->dev);
1373 master->num_chipselect = pdata->num_cs;
1374 if (pdev->id != -1)
1375 master->bus_num = pdev->id;
1376 mcspi->pin_dir = pdata->pin_dir;
1377 }
1378 regs_offset = pdata->regs_offset;
1379
1380 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1381 if (r == NULL) {
1382 status = -ENODEV;
1383 goto free_master;
1384 }
1385
1386 r->start += regs_offset;
1387 r->end += regs_offset;
1388 mcspi->phys = r->start;
1389
1390 mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1391 if (IS_ERR(mcspi->base)) {
1392 status = PTR_ERR(mcspi->base);
1393 goto free_master;
1394 }
1395
1396 mcspi->dev = &pdev->dev;
1397
1398 INIT_LIST_HEAD(&mcspi->ctx.cs);
1399
1400 mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1401 sizeof(struct omap2_mcspi_dma),
1402 GFP_KERNEL);
1403 if (mcspi->dma_channels == NULL) {
1404 status = -ENOMEM;
1405 goto free_master;
1406 }
1407
1408 for (i = 0; i < master->num_chipselect; i++) {
1409 char *dma_rx_ch_name = mcspi->dma_channels[i].dma_rx_ch_name;
1410 char *dma_tx_ch_name = mcspi->dma_channels[i].dma_tx_ch_name;
1411 struct resource *dma_res;
1412
1413 sprintf(dma_rx_ch_name, "rx%d", i);
1414 if (!pdev->dev.of_node) {
1415 dma_res =
1416 platform_get_resource_byname(pdev,
1417 IORESOURCE_DMA,
1418 dma_rx_ch_name);
1419 if (!dma_res) {
1420 dev_dbg(&pdev->dev,
1421 "cannot get DMA RX channel\n");
1422 status = -ENODEV;
1423 break;
1424 }
1425
1426 mcspi->dma_channels[i].dma_rx_sync_dev =
1427 dma_res->start;
1428 }
1429 sprintf(dma_tx_ch_name, "tx%d", i);
1430 if (!pdev->dev.of_node) {
1431 dma_res =
1432 platform_get_resource_byname(pdev,
1433 IORESOURCE_DMA,
1434 dma_tx_ch_name);
1435 if (!dma_res) {
1436 dev_dbg(&pdev->dev,
1437 "cannot get DMA TX channel\n");
1438 status = -ENODEV;
1439 break;
1440 }
1441
1442 mcspi->dma_channels[i].dma_tx_sync_dev =
1443 dma_res->start;
1444 }
1445 }
1446
1447 if (status < 0)
1448 goto free_master;
1449
1450 pm_runtime_use_autosuspend(&pdev->dev);
1451 pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1452 pm_runtime_enable(&pdev->dev);
1453
1454 status = omap2_mcspi_master_setup(mcspi);
1455 if (status < 0)
1456 goto disable_pm;
1457
1458 status = devm_spi_register_master(&pdev->dev, master);
1459 if (status < 0)
1460 goto disable_pm;
1461
1462 return status;
1463
1464 disable_pm:
1465 pm_runtime_dont_use_autosuspend(&pdev->dev);
1466 pm_runtime_put_sync(&pdev->dev);
1467 pm_runtime_disable(&pdev->dev);
1468 free_master:
1469 spi_master_put(master);
1470 return status;
1471 }
1472
1473 static int omap2_mcspi_remove(struct platform_device *pdev)
1474 {
1475 struct spi_master *master = platform_get_drvdata(pdev);
1476 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1477
1478 pm_runtime_dont_use_autosuspend(mcspi->dev);
1479 pm_runtime_put_sync(mcspi->dev);
1480 pm_runtime_disable(&pdev->dev);
1481
1482 return 0;
1483 }
1484
1485 /* work with hotplug and coldplug */
1486 MODULE_ALIAS("platform:omap2_mcspi");
1487
1488 #ifdef CONFIG_SUSPEND
1489 /*
1490 * When SPI wake up from off-mode, CS is in activate state. If it was in
1491 * unactive state when driver was suspend, then force it to unactive state at
1492 * wake up.
1493 */
1494 static int omap2_mcspi_resume(struct device *dev)
1495 {
1496 struct spi_master *master = dev_get_drvdata(dev);
1497 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1498 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1499 struct omap2_mcspi_cs *cs;
1500
1501 pm_runtime_get_sync(mcspi->dev);
1502 list_for_each_entry(cs, &ctx->cs, node) {
1503 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1504 /*
1505 * We need to toggle CS state for OMAP take this
1506 * change in account.
1507 */
1508 cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1509 writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1510 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1511 writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1512 }
1513 }
1514 pm_runtime_mark_last_busy(mcspi->dev);
1515 pm_runtime_put_autosuspend(mcspi->dev);
1516
1517 return pinctrl_pm_select_default_state(dev);
1518 }
1519
1520 static int omap2_mcspi_suspend(struct device *dev)
1521 {
1522 return pinctrl_pm_select_sleep_state(dev);
1523 }
1524
1525 #else
1526 #define omap2_mcspi_suspend NULL
1527 #define omap2_mcspi_resume NULL
1528 #endif
1529
1530 static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1531 .resume = omap2_mcspi_resume,
1532 .suspend = omap2_mcspi_suspend,
1533 .runtime_resume = omap_mcspi_runtime_resume,
1534 };
1535
1536 static struct platform_driver omap2_mcspi_driver = {
1537 .driver = {
1538 .name = "omap2_mcspi",
1539 .pm = &omap2_mcspi_pm_ops,
1540 .of_match_table = omap_mcspi_of_match,
1541 },
1542 .probe = omap2_mcspi_probe,
1543 .remove = omap2_mcspi_remove,
1544 };
1545
1546 module_platform_driver(omap2_mcspi_driver);
1547 MODULE_LICENSE("GPL");
Linux kernel - Deliverables
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