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Merge tag 'imx-clk-fixes-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/shawng...
[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 struct scatterlist sg;
427
428 dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
429
430 sg_init_table(&sg, 1);
431 sg_dma_address(&sg) = xfer->tx_dma;
432 sg_dma_len(&sg) = xfer->len;
433
434 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, &sg, 1,
435 DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
436 if (tx) {
437 tx->callback = omap2_mcspi_tx_callback;
438 tx->callback_param = spi;
439 dmaengine_submit(tx);
440 } else {
441 /* FIXME: fall back to PIO? */
442 }
443 }
444 dma_async_issue_pending(mcspi_dma->dma_tx);
445 omap2_mcspi_set_dma_req(spi, 0, 1);
446
447 }
448
449 static unsigned
450 omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
451 struct dma_slave_config cfg,
452 unsigned es)
453 {
454 struct omap2_mcspi *mcspi;
455 struct omap2_mcspi_dma *mcspi_dma;
456 unsigned int count, dma_count;
457 u32 l;
458 int elements = 0;
459 int word_len, element_count;
460 struct omap2_mcspi_cs *cs = spi->controller_state;
461 mcspi = spi_master_get_devdata(spi->master);
462 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
463 count = xfer->len;
464 dma_count = xfer->len;
465
466 if (mcspi->fifo_depth == 0)
467 dma_count -= es;
468
469 word_len = cs->word_len;
470 l = mcspi_cached_chconf0(spi);
471
472 if (word_len <= 8)
473 element_count = count;
474 else if (word_len <= 16)
475 element_count = count >> 1;
476 else /* word_len <= 32 */
477 element_count = count >> 2;
478
479 if (mcspi_dma->dma_rx) {
480 struct dma_async_tx_descriptor *tx;
481 struct scatterlist sg;
482
483 dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
484
485 if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
486 dma_count -= es;
487
488 sg_init_table(&sg, 1);
489 sg_dma_address(&sg) = xfer->rx_dma;
490 sg_dma_len(&sg) = dma_count;
491
492 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, &sg, 1,
493 DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT |
494 DMA_CTRL_ACK);
495 if (tx) {
496 tx->callback = omap2_mcspi_rx_callback;
497 tx->callback_param = spi;
498 dmaengine_submit(tx);
499 } else {
500 /* FIXME: fall back to PIO? */
501 }
502 }
503
504 dma_async_issue_pending(mcspi_dma->dma_rx);
505 omap2_mcspi_set_dma_req(spi, 1, 1);
506
507 wait_for_completion(&mcspi_dma->dma_rx_completion);
508 dma_unmap_single(mcspi->dev, xfer->rx_dma, count,
509 DMA_FROM_DEVICE);
510
511 if (mcspi->fifo_depth > 0)
512 return count;
513
514 omap2_mcspi_set_enable(spi, 0);
515
516 elements = element_count - 1;
517
518 if (l & OMAP2_MCSPI_CHCONF_TURBO) {
519 elements--;
520
521 if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
522 & OMAP2_MCSPI_CHSTAT_RXS)) {
523 u32 w;
524
525 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
526 if (word_len <= 8)
527 ((u8 *)xfer->rx_buf)[elements++] = w;
528 else if (word_len <= 16)
529 ((u16 *)xfer->rx_buf)[elements++] = w;
530 else /* word_len <= 32 */
531 ((u32 *)xfer->rx_buf)[elements++] = w;
532 } else {
533 int bytes_per_word = mcspi_bytes_per_word(word_len);
534 dev_err(&spi->dev, "DMA RX penultimate word empty\n");
535 count -= (bytes_per_word << 1);
536 omap2_mcspi_set_enable(spi, 1);
537 return count;
538 }
539 }
540 if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
541 & OMAP2_MCSPI_CHSTAT_RXS)) {
542 u32 w;
543
544 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
545 if (word_len <= 8)
546 ((u8 *)xfer->rx_buf)[elements] = w;
547 else if (word_len <= 16)
548 ((u16 *)xfer->rx_buf)[elements] = w;
549 else /* word_len <= 32 */
550 ((u32 *)xfer->rx_buf)[elements] = w;
551 } else {
552 dev_err(&spi->dev, "DMA RX last word empty\n");
553 count -= mcspi_bytes_per_word(word_len);
554 }
555 omap2_mcspi_set_enable(spi, 1);
556 return count;
557 }
558
559 static unsigned
560 omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
561 {
562 struct omap2_mcspi *mcspi;
563 struct omap2_mcspi_cs *cs = spi->controller_state;
564 struct omap2_mcspi_dma *mcspi_dma;
565 unsigned int count;
566 u32 l;
567 u8 *rx;
568 const u8 *tx;
569 struct dma_slave_config cfg;
570 enum dma_slave_buswidth width;
571 unsigned es;
572 u32 burst;
573 void __iomem *chstat_reg;
574 void __iomem *irqstat_reg;
575 int wait_res;
576
577 mcspi = spi_master_get_devdata(spi->master);
578 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
579 l = mcspi_cached_chconf0(spi);
580
581
582 if (cs->word_len <= 8) {
583 width = DMA_SLAVE_BUSWIDTH_1_BYTE;
584 es = 1;
585 } else if (cs->word_len <= 16) {
586 width = DMA_SLAVE_BUSWIDTH_2_BYTES;
587 es = 2;
588 } else {
589 width = DMA_SLAVE_BUSWIDTH_4_BYTES;
590 es = 4;
591 }
592
593 count = xfer->len;
594 burst = 1;
595
596 if (mcspi->fifo_depth > 0) {
597 if (count > mcspi->fifo_depth)
598 burst = mcspi->fifo_depth / es;
599 else
600 burst = count / es;
601 }
602
603 memset(&cfg, 0, sizeof(cfg));
604 cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
605 cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
606 cfg.src_addr_width = width;
607 cfg.dst_addr_width = width;
608 cfg.src_maxburst = burst;
609 cfg.dst_maxburst = burst;
610
611 rx = xfer->rx_buf;
612 tx = xfer->tx_buf;
613
614 if (tx != NULL)
615 omap2_mcspi_tx_dma(spi, xfer, cfg);
616
617 if (rx != NULL)
618 count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
619
620 if (tx != NULL) {
621 wait_for_completion(&mcspi_dma->dma_tx_completion);
622 dma_unmap_single(mcspi->dev, xfer->tx_dma, xfer->len,
623 DMA_TO_DEVICE);
624
625 if (mcspi->fifo_depth > 0) {
626 irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
627
628 if (mcspi_wait_for_reg_bit(irqstat_reg,
629 OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
630 dev_err(&spi->dev, "EOW timed out\n");
631
632 mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
633 OMAP2_MCSPI_IRQSTATUS_EOW);
634 }
635
636 /* for TX_ONLY mode, be sure all words have shifted out */
637 if (rx == NULL) {
638 chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
639 if (mcspi->fifo_depth > 0) {
640 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
641 OMAP2_MCSPI_CHSTAT_TXFFE);
642 if (wait_res < 0)
643 dev_err(&spi->dev, "TXFFE timed out\n");
644 } else {
645 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
646 OMAP2_MCSPI_CHSTAT_TXS);
647 if (wait_res < 0)
648 dev_err(&spi->dev, "TXS timed out\n");
649 }
650 if (wait_res >= 0 &&
651 (mcspi_wait_for_reg_bit(chstat_reg,
652 OMAP2_MCSPI_CHSTAT_EOT) < 0))
653 dev_err(&spi->dev, "EOT timed out\n");
654 }
655 }
656 return count;
657 }
658
659 static unsigned
660 omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
661 {
662 struct omap2_mcspi *mcspi;
663 struct omap2_mcspi_cs *cs = spi->controller_state;
664 unsigned int count, c;
665 u32 l;
666 void __iomem *base = cs->base;
667 void __iomem *tx_reg;
668 void __iomem *rx_reg;
669 void __iomem *chstat_reg;
670 int word_len;
671
672 mcspi = spi_master_get_devdata(spi->master);
673 count = xfer->len;
674 c = count;
675 word_len = cs->word_len;
676
677 l = mcspi_cached_chconf0(spi);
678
679 /* We store the pre-calculated register addresses on stack to speed
680 * up the transfer loop. */
681 tx_reg = base + OMAP2_MCSPI_TX0;
682 rx_reg = base + OMAP2_MCSPI_RX0;
683 chstat_reg = base + OMAP2_MCSPI_CHSTAT0;
684
685 if (c < (word_len>>3))
686 return 0;
687
688 if (word_len <= 8) {
689 u8 *rx;
690 const u8 *tx;
691
692 rx = xfer->rx_buf;
693 tx = xfer->tx_buf;
694
695 do {
696 c -= 1;
697 if (tx != NULL) {
698 if (mcspi_wait_for_reg_bit(chstat_reg,
699 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
700 dev_err(&spi->dev, "TXS timed out\n");
701 goto out;
702 }
703 dev_vdbg(&spi->dev, "write-%d %02x\n",
704 word_len, *tx);
705 writel_relaxed(*tx++, tx_reg);
706 }
707 if (rx != NULL) {
708 if (mcspi_wait_for_reg_bit(chstat_reg,
709 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
710 dev_err(&spi->dev, "RXS timed out\n");
711 goto out;
712 }
713
714 if (c == 1 && tx == NULL &&
715 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
716 omap2_mcspi_set_enable(spi, 0);
717 *rx++ = readl_relaxed(rx_reg);
718 dev_vdbg(&spi->dev, "read-%d %02x\n",
719 word_len, *(rx - 1));
720 if (mcspi_wait_for_reg_bit(chstat_reg,
721 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
722 dev_err(&spi->dev,
723 "RXS timed out\n");
724 goto out;
725 }
726 c = 0;
727 } else if (c == 0 && tx == NULL) {
728 omap2_mcspi_set_enable(spi, 0);
729 }
730
731 *rx++ = readl_relaxed(rx_reg);
732 dev_vdbg(&spi->dev, "read-%d %02x\n",
733 word_len, *(rx - 1));
734 }
735 } while (c);
736 } else if (word_len <= 16) {
737 u16 *rx;
738 const u16 *tx;
739
740 rx = xfer->rx_buf;
741 tx = xfer->tx_buf;
742 do {
743 c -= 2;
744 if (tx != NULL) {
745 if (mcspi_wait_for_reg_bit(chstat_reg,
746 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
747 dev_err(&spi->dev, "TXS timed out\n");
748 goto out;
749 }
750 dev_vdbg(&spi->dev, "write-%d %04x\n",
751 word_len, *tx);
752 writel_relaxed(*tx++, tx_reg);
753 }
754 if (rx != NULL) {
755 if (mcspi_wait_for_reg_bit(chstat_reg,
756 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
757 dev_err(&spi->dev, "RXS timed out\n");
758 goto out;
759 }
760
761 if (c == 2 && tx == NULL &&
762 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
763 omap2_mcspi_set_enable(spi, 0);
764 *rx++ = readl_relaxed(rx_reg);
765 dev_vdbg(&spi->dev, "read-%d %04x\n",
766 word_len, *(rx - 1));
767 if (mcspi_wait_for_reg_bit(chstat_reg,
768 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
769 dev_err(&spi->dev,
770 "RXS timed out\n");
771 goto out;
772 }
773 c = 0;
774 } else if (c == 0 && tx == NULL) {
775 omap2_mcspi_set_enable(spi, 0);
776 }
777
778 *rx++ = readl_relaxed(rx_reg);
779 dev_vdbg(&spi->dev, "read-%d %04x\n",
780 word_len, *(rx - 1));
781 }
782 } while (c >= 2);
783 } else if (word_len <= 32) {
784 u32 *rx;
785 const u32 *tx;
786
787 rx = xfer->rx_buf;
788 tx = xfer->tx_buf;
789 do {
790 c -= 4;
791 if (tx != NULL) {
792 if (mcspi_wait_for_reg_bit(chstat_reg,
793 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
794 dev_err(&spi->dev, "TXS timed out\n");
795 goto out;
796 }
797 dev_vdbg(&spi->dev, "write-%d %08x\n",
798 word_len, *tx);
799 writel_relaxed(*tx++, tx_reg);
800 }
801 if (rx != NULL) {
802 if (mcspi_wait_for_reg_bit(chstat_reg,
803 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
804 dev_err(&spi->dev, "RXS timed out\n");
805 goto out;
806 }
807
808 if (c == 4 && tx == NULL &&
809 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
810 omap2_mcspi_set_enable(spi, 0);
811 *rx++ = readl_relaxed(rx_reg);
812 dev_vdbg(&spi->dev, "read-%d %08x\n",
813 word_len, *(rx - 1));
814 if (mcspi_wait_for_reg_bit(chstat_reg,
815 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
816 dev_err(&spi->dev,
817 "RXS timed out\n");
818 goto out;
819 }
820 c = 0;
821 } else if (c == 0 && tx == NULL) {
822 omap2_mcspi_set_enable(spi, 0);
823 }
824
825 *rx++ = readl_relaxed(rx_reg);
826 dev_vdbg(&spi->dev, "read-%d %08x\n",
827 word_len, *(rx - 1));
828 }
829 } while (c >= 4);
830 }
831
832 /* for TX_ONLY mode, be sure all words have shifted out */
833 if (xfer->rx_buf == NULL) {
834 if (mcspi_wait_for_reg_bit(chstat_reg,
835 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
836 dev_err(&spi->dev, "TXS timed out\n");
837 } else if (mcspi_wait_for_reg_bit(chstat_reg,
838 OMAP2_MCSPI_CHSTAT_EOT) < 0)
839 dev_err(&spi->dev, "EOT timed out\n");
840
841 /* disable chan to purge rx datas received in TX_ONLY transfer,
842 * otherwise these rx datas will affect the direct following
843 * RX_ONLY transfer.
844 */
845 omap2_mcspi_set_enable(spi, 0);
846 }
847 out:
848 omap2_mcspi_set_enable(spi, 1);
849 return count - c;
850 }
851
852 static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
853 {
854 u32 div;
855
856 for (div = 0; div < 15; div++)
857 if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
858 return div;
859
860 return 15;
861 }
862
863 /* called only when no transfer is active to this device */
864 static int omap2_mcspi_setup_transfer(struct spi_device *spi,
865 struct spi_transfer *t)
866 {
867 struct omap2_mcspi_cs *cs = spi->controller_state;
868 struct omap2_mcspi *mcspi;
869 struct spi_master *spi_cntrl;
870 u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
871 u8 word_len = spi->bits_per_word;
872 u32 speed_hz = spi->max_speed_hz;
873
874 mcspi = spi_master_get_devdata(spi->master);
875 spi_cntrl = mcspi->master;
876
877 if (t != NULL && t->bits_per_word)
878 word_len = t->bits_per_word;
879
880 cs->word_len = word_len;
881
882 if (t && t->speed_hz)
883 speed_hz = t->speed_hz;
884
885 speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
886 if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
887 clkd = omap2_mcspi_calc_divisor(speed_hz);
888 speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
889 clkg = 0;
890 } else {
891 div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
892 speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
893 clkd = (div - 1) & 0xf;
894 extclk = (div - 1) >> 4;
895 clkg = OMAP2_MCSPI_CHCONF_CLKG;
896 }
897
898 l = mcspi_cached_chconf0(spi);
899
900 /* standard 4-wire master mode: SCK, MOSI/out, MISO/in, nCS
901 * REVISIT: this controller could support SPI_3WIRE mode.
902 */
903 if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
904 l &= ~OMAP2_MCSPI_CHCONF_IS;
905 l &= ~OMAP2_MCSPI_CHCONF_DPE1;
906 l |= OMAP2_MCSPI_CHCONF_DPE0;
907 } else {
908 l |= OMAP2_MCSPI_CHCONF_IS;
909 l |= OMAP2_MCSPI_CHCONF_DPE1;
910 l &= ~OMAP2_MCSPI_CHCONF_DPE0;
911 }
912
913 /* wordlength */
914 l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
915 l |= (word_len - 1) << 7;
916
917 /* set chipselect polarity; manage with FORCE */
918 if (!(spi->mode & SPI_CS_HIGH))
919 l |= OMAP2_MCSPI_CHCONF_EPOL; /* active-low; normal */
920 else
921 l &= ~OMAP2_MCSPI_CHCONF_EPOL;
922
923 /* set clock divisor */
924 l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
925 l |= clkd << 2;
926
927 /* set clock granularity */
928 l &= ~OMAP2_MCSPI_CHCONF_CLKG;
929 l |= clkg;
930 if (clkg) {
931 cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
932 cs->chctrl0 |= extclk << 8;
933 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
934 }
935
936 /* set SPI mode 0..3 */
937 if (spi->mode & SPI_CPOL)
938 l |= OMAP2_MCSPI_CHCONF_POL;
939 else
940 l &= ~OMAP2_MCSPI_CHCONF_POL;
941 if (spi->mode & SPI_CPHA)
942 l |= OMAP2_MCSPI_CHCONF_PHA;
943 else
944 l &= ~OMAP2_MCSPI_CHCONF_PHA;
945
946 mcspi_write_chconf0(spi, l);
947
948 cs->mode = spi->mode;
949
950 dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
951 speed_hz,
952 (spi->mode & SPI_CPHA) ? "trailing" : "leading",
953 (spi->mode & SPI_CPOL) ? "inverted" : "normal");
954
955 return 0;
956 }
957
958 /*
959 * Note that we currently allow DMA only if we get a channel
960 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
961 */
962 static int omap2_mcspi_request_dma(struct spi_device *spi)
963 {
964 struct spi_master *master = spi->master;
965 struct omap2_mcspi *mcspi;
966 struct omap2_mcspi_dma *mcspi_dma;
967 dma_cap_mask_t mask;
968 unsigned sig;
969
970 mcspi = spi_master_get_devdata(master);
971 mcspi_dma = mcspi->dma_channels + spi->chip_select;
972
973 init_completion(&mcspi_dma->dma_rx_completion);
974 init_completion(&mcspi_dma->dma_tx_completion);
975
976 dma_cap_zero(mask);
977 dma_cap_set(DMA_SLAVE, mask);
978 sig = mcspi_dma->dma_rx_sync_dev;
979
980 mcspi_dma->dma_rx =
981 dma_request_slave_channel_compat(mask, omap_dma_filter_fn,
982 &sig, &master->dev,
983 mcspi_dma->dma_rx_ch_name);
984 if (!mcspi_dma->dma_rx)
985 goto no_dma;
986
987 sig = mcspi_dma->dma_tx_sync_dev;
988 mcspi_dma->dma_tx =
989 dma_request_slave_channel_compat(mask, omap_dma_filter_fn,
990 &sig, &master->dev,
991 mcspi_dma->dma_tx_ch_name);
992
993 if (!mcspi_dma->dma_tx) {
994 dma_release_channel(mcspi_dma->dma_rx);
995 mcspi_dma->dma_rx = NULL;
996 goto no_dma;
997 }
998
999 return 0;
1000
1001 no_dma:
1002 dev_warn(&spi->dev, "not using DMA for McSPI\n");
1003 return -EAGAIN;
1004 }
1005
1006 static int omap2_mcspi_setup(struct spi_device *spi)
1007 {
1008 int ret;
1009 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1010 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1011 struct omap2_mcspi_dma *mcspi_dma;
1012 struct omap2_mcspi_cs *cs = spi->controller_state;
1013
1014 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1015
1016 if (!cs) {
1017 cs = kzalloc(sizeof *cs, GFP_KERNEL);
1018 if (!cs)
1019 return -ENOMEM;
1020 cs->base = mcspi->base + spi->chip_select * 0x14;
1021 cs->phys = mcspi->phys + spi->chip_select * 0x14;
1022 cs->mode = 0;
1023 cs->chconf0 = 0;
1024 cs->chctrl0 = 0;
1025 spi->controller_state = cs;
1026 /* Link this to context save list */
1027 list_add_tail(&cs->node, &ctx->cs);
1028
1029 if (gpio_is_valid(spi->cs_gpio)) {
1030 ret = gpio_request(spi->cs_gpio, dev_name(&spi->dev));
1031 if (ret) {
1032 dev_err(&spi->dev, "failed to request gpio\n");
1033 return ret;
1034 }
1035 gpio_direction_output(spi->cs_gpio,
1036 !(spi->mode & SPI_CS_HIGH));
1037 }
1038 }
1039
1040 if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) {
1041 ret = omap2_mcspi_request_dma(spi);
1042 if (ret < 0 && ret != -EAGAIN)
1043 return ret;
1044 }
1045
1046 ret = pm_runtime_get_sync(mcspi->dev);
1047 if (ret < 0)
1048 return ret;
1049
1050 ret = omap2_mcspi_setup_transfer(spi, NULL);
1051 pm_runtime_mark_last_busy(mcspi->dev);
1052 pm_runtime_put_autosuspend(mcspi->dev);
1053
1054 return ret;
1055 }
1056
1057 static void omap2_mcspi_cleanup(struct spi_device *spi)
1058 {
1059 struct omap2_mcspi *mcspi;
1060 struct omap2_mcspi_dma *mcspi_dma;
1061 struct omap2_mcspi_cs *cs;
1062
1063 mcspi = spi_master_get_devdata(spi->master);
1064
1065 if (spi->controller_state) {
1066 /* Unlink controller state from context save list */
1067 cs = spi->controller_state;
1068 list_del(&cs->node);
1069
1070 kfree(cs);
1071 }
1072
1073 if (spi->chip_select < spi->master->num_chipselect) {
1074 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1075
1076 if (mcspi_dma->dma_rx) {
1077 dma_release_channel(mcspi_dma->dma_rx);
1078 mcspi_dma->dma_rx = NULL;
1079 }
1080 if (mcspi_dma->dma_tx) {
1081 dma_release_channel(mcspi_dma->dma_tx);
1082 mcspi_dma->dma_tx = NULL;
1083 }
1084 }
1085
1086 if (gpio_is_valid(spi->cs_gpio))
1087 gpio_free(spi->cs_gpio);
1088 }
1089
1090 static int omap2_mcspi_work_one(struct omap2_mcspi *mcspi,
1091 struct spi_device *spi, struct spi_transfer *t)
1092 {
1093
1094 /* We only enable one channel at a time -- the one whose message is
1095 * -- although this controller would gladly
1096 * arbitrate among multiple channels. This corresponds to "single
1097 * channel" master mode. As a side effect, we need to manage the
1098 * chipselect with the FORCE bit ... CS != channel enable.
1099 */
1100
1101 struct spi_master *master;
1102 struct omap2_mcspi_dma *mcspi_dma;
1103 struct omap2_mcspi_cs *cs;
1104 struct omap2_mcspi_device_config *cd;
1105 int par_override = 0;
1106 int status = 0;
1107 u32 chconf;
1108
1109 master = spi->master;
1110 mcspi_dma = mcspi->dma_channels + spi->chip_select;
1111 cs = spi->controller_state;
1112 cd = spi->controller_data;
1113
1114 /*
1115 * The slave driver could have changed spi->mode in which case
1116 * it will be different from cs->mode (the current hardware setup).
1117 * If so, set par_override (even though its not a parity issue) so
1118 * omap2_mcspi_setup_transfer will be called to configure the hardware
1119 * with the correct mode on the first iteration of the loop below.
1120 */
1121 if (spi->mode != cs->mode)
1122 par_override = 1;
1123
1124 omap2_mcspi_set_enable(spi, 0);
1125
1126 if (gpio_is_valid(spi->cs_gpio))
1127 omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH);
1128
1129 if (par_override ||
1130 (t->speed_hz != spi->max_speed_hz) ||
1131 (t->bits_per_word != spi->bits_per_word)) {
1132 par_override = 1;
1133 status = omap2_mcspi_setup_transfer(spi, t);
1134 if (status < 0)
1135 goto out;
1136 if (t->speed_hz == spi->max_speed_hz &&
1137 t->bits_per_word == spi->bits_per_word)
1138 par_override = 0;
1139 }
1140 if (cd && cd->cs_per_word) {
1141 chconf = mcspi->ctx.modulctrl;
1142 chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1143 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1144 mcspi->ctx.modulctrl =
1145 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1146 }
1147
1148 chconf = mcspi_cached_chconf0(spi);
1149 chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1150 chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
1151
1152 if (t->tx_buf == NULL)
1153 chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1154 else if (t->rx_buf == NULL)
1155 chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1156
1157 if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1158 /* Turbo mode is for more than one word */
1159 if (t->len > ((cs->word_len + 7) >> 3))
1160 chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1161 }
1162
1163 mcspi_write_chconf0(spi, chconf);
1164
1165 if (t->len) {
1166 unsigned count;
1167
1168 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1169 (t->len >= DMA_MIN_BYTES))
1170 omap2_mcspi_set_fifo(spi, t, 1);
1171
1172 omap2_mcspi_set_enable(spi, 1);
1173
1174 /* RX_ONLY mode needs dummy data in TX reg */
1175 if (t->tx_buf == NULL)
1176 writel_relaxed(0, cs->base
1177 + OMAP2_MCSPI_TX0);
1178
1179 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1180 (t->len >= DMA_MIN_BYTES))
1181 count = omap2_mcspi_txrx_dma(spi, t);
1182 else
1183 count = omap2_mcspi_txrx_pio(spi, t);
1184
1185 if (count != t->len) {
1186 status = -EIO;
1187 goto out;
1188 }
1189 }
1190
1191 omap2_mcspi_set_enable(spi, 0);
1192
1193 if (mcspi->fifo_depth > 0)
1194 omap2_mcspi_set_fifo(spi, t, 0);
1195
1196 out:
1197 /* Restore defaults if they were overriden */
1198 if (par_override) {
1199 par_override = 0;
1200 status = omap2_mcspi_setup_transfer(spi, NULL);
1201 }
1202
1203 if (cd && cd->cs_per_word) {
1204 chconf = mcspi->ctx.modulctrl;
1205 chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1206 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1207 mcspi->ctx.modulctrl =
1208 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1209 }
1210
1211 omap2_mcspi_set_enable(spi, 0);
1212
1213 if (gpio_is_valid(spi->cs_gpio))
1214 omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
1215
1216 if (mcspi->fifo_depth > 0 && t)
1217 omap2_mcspi_set_fifo(spi, t, 0);
1218
1219 return status;
1220 }
1221
1222 static int omap2_mcspi_prepare_message(struct spi_master *master,
1223 struct spi_message *msg)
1224 {
1225 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1226 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1227 struct omap2_mcspi_cs *cs;
1228
1229 /* Only a single channel can have the FORCE bit enabled
1230 * in its chconf0 register.
1231 * Scan all channels and disable them except the current one.
1232 * A FORCE can remain from a last transfer having cs_change enabled
1233 */
1234 list_for_each_entry(cs, &ctx->cs, node) {
1235 if (msg->spi->controller_state == cs)
1236 continue;
1237
1238 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
1239 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1240 writel_relaxed(cs->chconf0,
1241 cs->base + OMAP2_MCSPI_CHCONF0);
1242 readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
1243 }
1244 }
1245
1246 return 0;
1247 }
1248
1249 static int omap2_mcspi_transfer_one(struct spi_master *master,
1250 struct spi_device *spi, struct spi_transfer *t)
1251 {
1252 struct omap2_mcspi *mcspi;
1253 struct omap2_mcspi_dma *mcspi_dma;
1254 const void *tx_buf = t->tx_buf;
1255 void *rx_buf = t->rx_buf;
1256 unsigned len = t->len;
1257
1258 mcspi = spi_master_get_devdata(master);
1259 mcspi_dma = mcspi->dma_channels + spi->chip_select;
1260
1261 if ((len && !(rx_buf || tx_buf))) {
1262 dev_dbg(mcspi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
1263 t->speed_hz,
1264 len,
1265 tx_buf ? "tx" : "",
1266 rx_buf ? "rx" : "",
1267 t->bits_per_word);
1268 return -EINVAL;
1269 }
1270
1271 if (len < DMA_MIN_BYTES)
1272 goto skip_dma_map;
1273
1274 if (mcspi_dma->dma_tx && tx_buf != NULL) {
1275 t->tx_dma = dma_map_single(mcspi->dev, (void *) tx_buf,
1276 len, DMA_TO_DEVICE);
1277 if (dma_mapping_error(mcspi->dev, t->tx_dma)) {
1278 dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1279 'T', len);
1280 return -EINVAL;
1281 }
1282 }
1283 if (mcspi_dma->dma_rx && rx_buf != NULL) {
1284 t->rx_dma = dma_map_single(mcspi->dev, rx_buf, t->len,
1285 DMA_FROM_DEVICE);
1286 if (dma_mapping_error(mcspi->dev, t->rx_dma)) {
1287 dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1288 'R', len);
1289 if (tx_buf != NULL)
1290 dma_unmap_single(mcspi->dev, t->tx_dma,
1291 len, DMA_TO_DEVICE);
1292 return -EINVAL;
1293 }
1294 }
1295
1296 skip_dma_map:
1297 return omap2_mcspi_work_one(mcspi, spi, t);
1298 }
1299
1300 static int omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
1301 {
1302 struct spi_master *master = mcspi->master;
1303 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1304 int ret = 0;
1305
1306 ret = pm_runtime_get_sync(mcspi->dev);
1307 if (ret < 0)
1308 return ret;
1309
1310 mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1311 OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1312 ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1313
1314 omap2_mcspi_set_master_mode(master);
1315 pm_runtime_mark_last_busy(mcspi->dev);
1316 pm_runtime_put_autosuspend(mcspi->dev);
1317 return 0;
1318 }
1319
1320 static int omap_mcspi_runtime_resume(struct device *dev)
1321 {
1322 struct omap2_mcspi *mcspi;
1323 struct spi_master *master;
1324
1325 master = dev_get_drvdata(dev);
1326 mcspi = spi_master_get_devdata(master);
1327 omap2_mcspi_restore_ctx(mcspi);
1328
1329 return 0;
1330 }
1331
1332 static struct omap2_mcspi_platform_config omap2_pdata = {
1333 .regs_offset = 0,
1334 };
1335
1336 static struct omap2_mcspi_platform_config omap4_pdata = {
1337 .regs_offset = OMAP4_MCSPI_REG_OFFSET,
1338 };
1339
1340 static const struct of_device_id omap_mcspi_of_match[] = {
1341 {
1342 .compatible = "ti,omap2-mcspi",
1343 .data = &omap2_pdata,
1344 },
1345 {
1346 .compatible = "ti,omap4-mcspi",
1347 .data = &omap4_pdata,
1348 },
1349 { },
1350 };
1351 MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1352
1353 static int omap2_mcspi_probe(struct platform_device *pdev)
1354 {
1355 struct spi_master *master;
1356 const struct omap2_mcspi_platform_config *pdata;
1357 struct omap2_mcspi *mcspi;
1358 struct resource *r;
1359 int status = 0, i;
1360 u32 regs_offset = 0;
1361 static int bus_num = 1;
1362 struct device_node *node = pdev->dev.of_node;
1363 const struct of_device_id *match;
1364
1365 master = spi_alloc_master(&pdev->dev, sizeof *mcspi);
1366 if (master == NULL) {
1367 dev_dbg(&pdev->dev, "master allocation failed\n");
1368 return -ENOMEM;
1369 }
1370
1371 /* the spi->mode bits understood by this driver: */
1372 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1373 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1374 master->setup = omap2_mcspi_setup;
1375 master->auto_runtime_pm = true;
1376 master->prepare_message = omap2_mcspi_prepare_message;
1377 master->transfer_one = omap2_mcspi_transfer_one;
1378 master->set_cs = omap2_mcspi_set_cs;
1379 master->cleanup = omap2_mcspi_cleanup;
1380 master->dev.of_node = node;
1381 master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1382 master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
1383
1384 platform_set_drvdata(pdev, master);
1385
1386 mcspi = spi_master_get_devdata(master);
1387 mcspi->master = master;
1388
1389 match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1390 if (match) {
1391 u32 num_cs = 1; /* default number of chipselect */
1392 pdata = match->data;
1393
1394 of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1395 master->num_chipselect = num_cs;
1396 master->bus_num = bus_num++;
1397 if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1398 mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1399 } else {
1400 pdata = dev_get_platdata(&pdev->dev);
1401 master->num_chipselect = pdata->num_cs;
1402 if (pdev->id != -1)
1403 master->bus_num = pdev->id;
1404 mcspi->pin_dir = pdata->pin_dir;
1405 }
1406 regs_offset = pdata->regs_offset;
1407
1408 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1409 if (r == NULL) {
1410 status = -ENODEV;
1411 goto free_master;
1412 }
1413
1414 r->start += regs_offset;
1415 r->end += regs_offset;
1416 mcspi->phys = r->start;
1417
1418 mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1419 if (IS_ERR(mcspi->base)) {
1420 status = PTR_ERR(mcspi->base);
1421 goto free_master;
1422 }
1423
1424 mcspi->dev = &pdev->dev;
1425
1426 INIT_LIST_HEAD(&mcspi->ctx.cs);
1427
1428 mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1429 sizeof(struct omap2_mcspi_dma),
1430 GFP_KERNEL);
1431 if (mcspi->dma_channels == NULL) {
1432 status = -ENOMEM;
1433 goto free_master;
1434 }
1435
1436 for (i = 0; i < master->num_chipselect; i++) {
1437 char *dma_rx_ch_name = mcspi->dma_channels[i].dma_rx_ch_name;
1438 char *dma_tx_ch_name = mcspi->dma_channels[i].dma_tx_ch_name;
1439 struct resource *dma_res;
1440
1441 sprintf(dma_rx_ch_name, "rx%d", i);
1442 if (!pdev->dev.of_node) {
1443 dma_res =
1444 platform_get_resource_byname(pdev,
1445 IORESOURCE_DMA,
1446 dma_rx_ch_name);
1447 if (!dma_res) {
1448 dev_dbg(&pdev->dev,
1449 "cannot get DMA RX channel\n");
1450 status = -ENODEV;
1451 break;
1452 }
1453
1454 mcspi->dma_channels[i].dma_rx_sync_dev =
1455 dma_res->start;
1456 }
1457 sprintf(dma_tx_ch_name, "tx%d", i);
1458 if (!pdev->dev.of_node) {
1459 dma_res =
1460 platform_get_resource_byname(pdev,
1461 IORESOURCE_DMA,
1462 dma_tx_ch_name);
1463 if (!dma_res) {
1464 dev_dbg(&pdev->dev,
1465 "cannot get DMA TX channel\n");
1466 status = -ENODEV;
1467 break;
1468 }
1469
1470 mcspi->dma_channels[i].dma_tx_sync_dev =
1471 dma_res->start;
1472 }
1473 }
1474
1475 if (status < 0)
1476 goto free_master;
1477
1478 pm_runtime_use_autosuspend(&pdev->dev);
1479 pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1480 pm_runtime_enable(&pdev->dev);
1481
1482 status = omap2_mcspi_master_setup(mcspi);
1483 if (status < 0)
1484 goto disable_pm;
1485
1486 status = devm_spi_register_master(&pdev->dev, master);
1487 if (status < 0)
1488 goto disable_pm;
1489
1490 return status;
1491
1492 disable_pm:
1493 pm_runtime_dont_use_autosuspend(&pdev->dev);
1494 pm_runtime_put_sync(&pdev->dev);
1495 pm_runtime_disable(&pdev->dev);
1496 free_master:
1497 spi_master_put(master);
1498 return status;
1499 }
1500
1501 static int omap2_mcspi_remove(struct platform_device *pdev)
1502 {
1503 struct spi_master *master = platform_get_drvdata(pdev);
1504 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1505
1506 pm_runtime_dont_use_autosuspend(mcspi->dev);
1507 pm_runtime_put_sync(mcspi->dev);
1508 pm_runtime_disable(&pdev->dev);
1509
1510 return 0;
1511 }
1512
1513 /* work with hotplug and coldplug */
1514 MODULE_ALIAS("platform:omap2_mcspi");
1515
1516 #ifdef CONFIG_SUSPEND
1517 /*
1518 * When SPI wake up from off-mode, CS is in activate state. If it was in
1519 * unactive state when driver was suspend, then force it to unactive state at
1520 * wake up.
1521 */
1522 static int omap2_mcspi_resume(struct device *dev)
1523 {
1524 struct spi_master *master = dev_get_drvdata(dev);
1525 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1526 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1527 struct omap2_mcspi_cs *cs;
1528
1529 pm_runtime_get_sync(mcspi->dev);
1530 list_for_each_entry(cs, &ctx->cs, node) {
1531 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1532 /*
1533 * We need to toggle CS state for OMAP take this
1534 * change in account.
1535 */
1536 cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1537 writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1538 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1539 writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1540 }
1541 }
1542 pm_runtime_mark_last_busy(mcspi->dev);
1543 pm_runtime_put_autosuspend(mcspi->dev);
1544
1545 return pinctrl_pm_select_default_state(dev);
1546 }
1547
1548 static int omap2_mcspi_suspend(struct device *dev)
1549 {
1550 return pinctrl_pm_select_sleep_state(dev);
1551 }
1552
1553 #else
1554 #define omap2_mcspi_suspend NULL
1555 #define omap2_mcspi_resume NULL
1556 #endif
1557
1558 static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1559 .resume = omap2_mcspi_resume,
1560 .suspend = omap2_mcspi_suspend,
1561 .runtime_resume = omap_mcspi_runtime_resume,
1562 };
1563
1564 static struct platform_driver omap2_mcspi_driver = {
1565 .driver = {
1566 .name = "omap2_mcspi",
1567 .pm = &omap2_mcspi_pm_ops,
1568 .of_match_table = omap_mcspi_of_match,
1569 },
1570 .probe = omap2_mcspi_probe,
1571 .remove = omap2_mcspi_remove,
1572 };
1573
1574 module_platform_driver(omap2_mcspi_driver);
1575 MODULE_LICENSE("GPL");
Linux kernel - Deliverables
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