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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 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 *
22 */
23
24#include <linux/kernel.h>
25#include <linux/init.h>
26#include <linux/interrupt.h>
27#include <linux/module.h>
28#include <linux/device.h>
29#include <linux/delay.h>
30#include <linux/dma-mapping.h>
31#include <linux/platform_device.h>
32#include <linux/err.h>
33#include <linux/clk.h>
34#include <linux/io.h>
35#include <linux/slab.h>
36#include <linux/pm_runtime.h>
37#include <linux/of.h>
38#include <linux/of_device.h>
39
40#include <linux/spi/spi.h>
41
42#include <plat/dma.h>
43#include <plat/clock.h>
44#include <plat/mcspi.h>
45
46#define OMAP2_MCSPI_MAX_FREQ 48000000
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
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
66#define OMAP2_MCSPI_MODULCTRL_SINGLE BIT(0)
67#define OMAP2_MCSPI_MODULCTRL_MS BIT(2)
68#define OMAP2_MCSPI_MODULCTRL_STEST BIT(3)
69
70#define OMAP2_MCSPI_CHCONF_PHA BIT(0)
71#define OMAP2_MCSPI_CHCONF_POL BIT(1)
72#define OMAP2_MCSPI_CHCONF_CLKD_MASK (0x0f << 2)
73#define OMAP2_MCSPI_CHCONF_EPOL BIT(6)
74#define OMAP2_MCSPI_CHCONF_WL_MASK (0x1f << 7)
75#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY BIT(12)
76#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY BIT(13)
77#define OMAP2_MCSPI_CHCONF_TRM_MASK (0x03 << 12)
78#define OMAP2_MCSPI_CHCONF_DMAW BIT(14)
79#define OMAP2_MCSPI_CHCONF_DMAR BIT(15)
80#define OMAP2_MCSPI_CHCONF_DPE0 BIT(16)
81#define OMAP2_MCSPI_CHCONF_DPE1 BIT(17)
82#define OMAP2_MCSPI_CHCONF_IS BIT(18)
83#define OMAP2_MCSPI_CHCONF_TURBO BIT(19)
84#define OMAP2_MCSPI_CHCONF_FORCE BIT(20)
85
86#define OMAP2_MCSPI_CHSTAT_RXS BIT(0)
87#define OMAP2_MCSPI_CHSTAT_TXS BIT(1)
88#define OMAP2_MCSPI_CHSTAT_EOT BIT(2)
89
90#define OMAP2_MCSPI_CHCTRL_EN BIT(0)
91
92#define OMAP2_MCSPI_WAKEUPENABLE_WKEN BIT(0)
93
94/* We have 2 DMA channels per CS, one for RX and one for TX */
95struct omap2_mcspi_dma {
96 int dma_tx_channel;
97 int dma_rx_channel;
98
99 int dma_tx_sync_dev;
100 int dma_rx_sync_dev;
101
102 struct completion dma_tx_completion;
103 struct completion dma_rx_completion;
104};
105
106/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
107 * cache operations; better heuristics consider wordsize and bitrate.
108 */
109#define DMA_MIN_BYTES 160
110
111
112/*
113 * Used for context save and restore, structure members to be updated whenever
114 * corresponding registers are modified.
115 */
116struct omap2_mcspi_regs {
117 u32 modulctrl;
118 u32 wakeupenable;
119 struct list_head cs;
120};
121
122struct omap2_mcspi {
123 struct spi_master *master;
124 /* Virtual base address of the controller */
125 void __iomem *base;
126 unsigned long phys;
127 /* SPI1 has 4 channels, while SPI2 has 2 */
128 struct omap2_mcspi_dma *dma_channels;
129 struct device *dev;
130 struct omap2_mcspi_regs ctx;
131};
132
133struct omap2_mcspi_cs {
134 void __iomem *base;
135 unsigned long phys;
136 int word_len;
137 struct list_head node;
138 /* Context save and restore shadow register */
139 u32 chconf0;
140};
141
142#define MOD_REG_BIT(val, mask, set) do { \
143 if (set) \
144 val |= mask; \
145 else \
146 val &= ~mask; \
147} while (0)
148
149static inline void mcspi_write_reg(struct spi_master *master,
150 int idx, u32 val)
151{
152 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
153
154 __raw_writel(val, mcspi->base + idx);
155}
156
157static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
158{
159 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
160
161 return __raw_readl(mcspi->base + idx);
162}
163
164static inline void mcspi_write_cs_reg(const struct spi_device *spi,
165 int idx, u32 val)
166{
167 struct omap2_mcspi_cs *cs = spi->controller_state;
168
169 __raw_writel(val, cs->base + idx);
170}
171
172static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
173{
174 struct omap2_mcspi_cs *cs = spi->controller_state;
175
176 return __raw_readl(cs->base + idx);
177}
178
179static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
180{
181 struct omap2_mcspi_cs *cs = spi->controller_state;
182
183 return cs->chconf0;
184}
185
186static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
187{
188 struct omap2_mcspi_cs *cs = spi->controller_state;
189
190 cs->chconf0 = val;
191 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
192 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
193}
194
195static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
196 int is_read, int enable)
197{
198 u32 l, rw;
199
200 l = mcspi_cached_chconf0(spi);
201
202 if (is_read) /* 1 is read, 0 write */
203 rw = OMAP2_MCSPI_CHCONF_DMAR;
204 else
205 rw = OMAP2_MCSPI_CHCONF_DMAW;
206
207 MOD_REG_BIT(l, rw, enable);
208 mcspi_write_chconf0(spi, l);
209}
210
211static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
212{
213 u32 l;
214
215 l = enable ? OMAP2_MCSPI_CHCTRL_EN : 0;
216 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, l);
217 /* Flash post-writes */
218 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
219}
220
221static void omap2_mcspi_force_cs(struct spi_device *spi, int cs_active)
222{
223 u32 l;
224
225 l = mcspi_cached_chconf0(spi);
226 MOD_REG_BIT(l, OMAP2_MCSPI_CHCONF_FORCE, cs_active);
227 mcspi_write_chconf0(spi, l);
228}
229
230static void omap2_mcspi_set_master_mode(struct spi_master *master)
231{
232 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
233 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
234 u32 l;
235
236 /*
237 * Setup when switching from (reset default) slave mode
238 * to single-channel master mode
239 */
240 l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
241 MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_STEST, 0);
242 MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_MS, 0);
243 MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_SINGLE, 1);
244 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
245
246 ctx->modulctrl = l;
247}
248
249static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
250{
251 struct spi_master *spi_cntrl = mcspi->master;
252 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
253 struct omap2_mcspi_cs *cs;
254
255 /* McSPI: context restore */
256 mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
257 mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
258
259 list_for_each_entry(cs, &ctx->cs, node)
260 __raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
261}
262static void omap2_mcspi_disable_clocks(struct omap2_mcspi *mcspi)
263{
264 pm_runtime_mark_last_busy(mcspi->dev);
265 pm_runtime_put_autosuspend(mcspi->dev);
266}
267
268static int omap2_mcspi_enable_clocks(struct omap2_mcspi *mcspi)
269{
270 return pm_runtime_get_sync(mcspi->dev);
271}
272
273static int omap2_prepare_transfer(struct spi_master *master)
274{
275 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
276
277 pm_runtime_get_sync(mcspi->dev);
278 return 0;
279}
280
281static int omap2_unprepare_transfer(struct spi_master *master)
282{
283 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
284
285 pm_runtime_mark_last_busy(mcspi->dev);
286 pm_runtime_put_autosuspend(mcspi->dev);
287 return 0;
288}
289
290static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
291{
292 unsigned long timeout;
293
294 timeout = jiffies + msecs_to_jiffies(1000);
295 while (!(__raw_readl(reg) & bit)) {
296 if (time_after(jiffies, timeout))
297 return -1;
298 cpu_relax();
299 }
300 return 0;
301}
302
303static unsigned
304omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
305{
306 struct omap2_mcspi *mcspi;
307 struct omap2_mcspi_cs *cs = spi->controller_state;
308 struct omap2_mcspi_dma *mcspi_dma;
309 unsigned int count, c;
310 unsigned long base, tx_reg, rx_reg;
311 int word_len, data_type, element_count;
312 int elements = 0;
313 u32 l;
314 u8 * rx;
315 const u8 * tx;
316 void __iomem *chstat_reg;
317
318 mcspi = spi_master_get_devdata(spi->master);
319 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
320 l = mcspi_cached_chconf0(spi);
321
322 chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
323
324 count = xfer->len;
325 c = count;
326 word_len = cs->word_len;
327
328 base = cs->phys;
329 tx_reg = base + OMAP2_MCSPI_TX0;
330 rx_reg = base + OMAP2_MCSPI_RX0;
331 rx = xfer->rx_buf;
332 tx = xfer->tx_buf;
333
334 if (word_len <= 8) {
335 data_type = OMAP_DMA_DATA_TYPE_S8;
336 element_count = count;
337 } else if (word_len <= 16) {
338 data_type = OMAP_DMA_DATA_TYPE_S16;
339 element_count = count >> 1;
340 } else /* word_len <= 32 */ {
341 data_type = OMAP_DMA_DATA_TYPE_S32;
342 element_count = count >> 2;
343 }
344
345 if (tx != NULL) {
346 omap_set_dma_transfer_params(mcspi_dma->dma_tx_channel,
347 data_type, element_count, 1,
348 OMAP_DMA_SYNC_ELEMENT,
349 mcspi_dma->dma_tx_sync_dev, 0);
350
351 omap_set_dma_dest_params(mcspi_dma->dma_tx_channel, 0,
352 OMAP_DMA_AMODE_CONSTANT,
353 tx_reg, 0, 0);
354
355 omap_set_dma_src_params(mcspi_dma->dma_tx_channel, 0,
356 OMAP_DMA_AMODE_POST_INC,
357 xfer->tx_dma, 0, 0);
358 }
359
360 if (rx != NULL) {
361 elements = element_count - 1;
362 if (l & OMAP2_MCSPI_CHCONF_TURBO)
363 elements--;
364
365 omap_set_dma_transfer_params(mcspi_dma->dma_rx_channel,
366 data_type, elements, 1,
367 OMAP_DMA_SYNC_ELEMENT,
368 mcspi_dma->dma_rx_sync_dev, 1);
369
370 omap_set_dma_src_params(mcspi_dma->dma_rx_channel, 0,
371 OMAP_DMA_AMODE_CONSTANT,
372 rx_reg, 0, 0);
373
374 omap_set_dma_dest_params(mcspi_dma->dma_rx_channel, 0,
375 OMAP_DMA_AMODE_POST_INC,
376 xfer->rx_dma, 0, 0);
377 }
378
379 if (tx != NULL) {
380 omap_start_dma(mcspi_dma->dma_tx_channel);
381 omap2_mcspi_set_dma_req(spi, 0, 1);
382 }
383
384 if (rx != NULL) {
385 omap_start_dma(mcspi_dma->dma_rx_channel);
386 omap2_mcspi_set_dma_req(spi, 1, 1);
387 }
388
389 if (tx != NULL) {
390 wait_for_completion(&mcspi_dma->dma_tx_completion);
391 dma_unmap_single(&spi->dev, xfer->tx_dma, count, DMA_TO_DEVICE);
392
393 /* for TX_ONLY mode, be sure all words have shifted out */
394 if (rx == NULL) {
395 if (mcspi_wait_for_reg_bit(chstat_reg,
396 OMAP2_MCSPI_CHSTAT_TXS) < 0)
397 dev_err(&spi->dev, "TXS timed out\n");
398 else if (mcspi_wait_for_reg_bit(chstat_reg,
399 OMAP2_MCSPI_CHSTAT_EOT) < 0)
400 dev_err(&spi->dev, "EOT timed out\n");
401 }
402 }
403
404 if (rx != NULL) {
405 wait_for_completion(&mcspi_dma->dma_rx_completion);
406 dma_unmap_single(&spi->dev, xfer->rx_dma, count, DMA_FROM_DEVICE);
407 omap2_mcspi_set_enable(spi, 0);
408
409 if (l & OMAP2_MCSPI_CHCONF_TURBO) {
410
411 if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
412 & OMAP2_MCSPI_CHSTAT_RXS)) {
413 u32 w;
414
415 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
416 if (word_len <= 8)
417 ((u8 *)xfer->rx_buf)[elements++] = w;
418 else if (word_len <= 16)
419 ((u16 *)xfer->rx_buf)[elements++] = w;
420 else /* word_len <= 32 */
421 ((u32 *)xfer->rx_buf)[elements++] = w;
422 } else {
423 dev_err(&spi->dev,
424 "DMA RX penultimate word empty");
425 count -= (word_len <= 8) ? 2 :
426 (word_len <= 16) ? 4 :
427 /* word_len <= 32 */ 8;
428 omap2_mcspi_set_enable(spi, 1);
429 return count;
430 }
431 }
432
433 if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
434 & OMAP2_MCSPI_CHSTAT_RXS)) {
435 u32 w;
436
437 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
438 if (word_len <= 8)
439 ((u8 *)xfer->rx_buf)[elements] = w;
440 else if (word_len <= 16)
441 ((u16 *)xfer->rx_buf)[elements] = w;
442 else /* word_len <= 32 */
443 ((u32 *)xfer->rx_buf)[elements] = w;
444 } else {
445 dev_err(&spi->dev, "DMA RX last word empty");
446 count -= (word_len <= 8) ? 1 :
447 (word_len <= 16) ? 2 :
448 /* word_len <= 32 */ 4;
449 }
450 omap2_mcspi_set_enable(spi, 1);
451 }
452 return count;
453}
454
455static unsigned
456omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
457{
458 struct omap2_mcspi *mcspi;
459 struct omap2_mcspi_cs *cs = spi->controller_state;
460 unsigned int count, c;
461 u32 l;
462 void __iomem *base = cs->base;
463 void __iomem *tx_reg;
464 void __iomem *rx_reg;
465 void __iomem *chstat_reg;
466 int word_len;
467
468 mcspi = spi_master_get_devdata(spi->master);
469 count = xfer->len;
470 c = count;
471 word_len = cs->word_len;
472
473 l = mcspi_cached_chconf0(spi);
474
475 /* We store the pre-calculated register addresses on stack to speed
476 * up the transfer loop. */
477 tx_reg = base + OMAP2_MCSPI_TX0;
478 rx_reg = base + OMAP2_MCSPI_RX0;
479 chstat_reg = base + OMAP2_MCSPI_CHSTAT0;
480
481 if (c < (word_len>>3))
482 return 0;
483
484 if (word_len <= 8) {
485 u8 *rx;
486 const u8 *tx;
487
488 rx = xfer->rx_buf;
489 tx = xfer->tx_buf;
490
491 do {
492 c -= 1;
493 if (tx != NULL) {
494 if (mcspi_wait_for_reg_bit(chstat_reg,
495 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
496 dev_err(&spi->dev, "TXS timed out\n");
497 goto out;
498 }
499 dev_vdbg(&spi->dev, "write-%d %02x\n",
500 word_len, *tx);
501 __raw_writel(*tx++, tx_reg);
502 }
503 if (rx != NULL) {
504 if (mcspi_wait_for_reg_bit(chstat_reg,
505 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
506 dev_err(&spi->dev, "RXS timed out\n");
507 goto out;
508 }
509
510 if (c == 1 && tx == NULL &&
511 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
512 omap2_mcspi_set_enable(spi, 0);
513 *rx++ = __raw_readl(rx_reg);
514 dev_vdbg(&spi->dev, "read-%d %02x\n",
515 word_len, *(rx - 1));
516 if (mcspi_wait_for_reg_bit(chstat_reg,
517 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
518 dev_err(&spi->dev,
519 "RXS timed out\n");
520 goto out;
521 }
522 c = 0;
523 } else if (c == 0 && tx == NULL) {
524 omap2_mcspi_set_enable(spi, 0);
525 }
526
527 *rx++ = __raw_readl(rx_reg);
528 dev_vdbg(&spi->dev, "read-%d %02x\n",
529 word_len, *(rx - 1));
530 }
531 } while (c);
532 } else if (word_len <= 16) {
533 u16 *rx;
534 const u16 *tx;
535
536 rx = xfer->rx_buf;
537 tx = xfer->tx_buf;
538 do {
539 c -= 2;
540 if (tx != NULL) {
541 if (mcspi_wait_for_reg_bit(chstat_reg,
542 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
543 dev_err(&spi->dev, "TXS timed out\n");
544 goto out;
545 }
546 dev_vdbg(&spi->dev, "write-%d %04x\n",
547 word_len, *tx);
548 __raw_writel(*tx++, tx_reg);
549 }
550 if (rx != NULL) {
551 if (mcspi_wait_for_reg_bit(chstat_reg,
552 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
553 dev_err(&spi->dev, "RXS timed out\n");
554 goto out;
555 }
556
557 if (c == 2 && tx == NULL &&
558 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
559 omap2_mcspi_set_enable(spi, 0);
560 *rx++ = __raw_readl(rx_reg);
561 dev_vdbg(&spi->dev, "read-%d %04x\n",
562 word_len, *(rx - 1));
563 if (mcspi_wait_for_reg_bit(chstat_reg,
564 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
565 dev_err(&spi->dev,
566 "RXS timed out\n");
567 goto out;
568 }
569 c = 0;
570 } else if (c == 0 && tx == NULL) {
571 omap2_mcspi_set_enable(spi, 0);
572 }
573
574 *rx++ = __raw_readl(rx_reg);
575 dev_vdbg(&spi->dev, "read-%d %04x\n",
576 word_len, *(rx - 1));
577 }
578 } while (c >= 2);
579 } else if (word_len <= 32) {
580 u32 *rx;
581 const u32 *tx;
582
583 rx = xfer->rx_buf;
584 tx = xfer->tx_buf;
585 do {
586 c -= 4;
587 if (tx != NULL) {
588 if (mcspi_wait_for_reg_bit(chstat_reg,
589 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
590 dev_err(&spi->dev, "TXS timed out\n");
591 goto out;
592 }
593 dev_vdbg(&spi->dev, "write-%d %08x\n",
594 word_len, *tx);
595 __raw_writel(*tx++, tx_reg);
596 }
597 if (rx != NULL) {
598 if (mcspi_wait_for_reg_bit(chstat_reg,
599 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
600 dev_err(&spi->dev, "RXS timed out\n");
601 goto out;
602 }
603
604 if (c == 4 && tx == NULL &&
605 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
606 omap2_mcspi_set_enable(spi, 0);
607 *rx++ = __raw_readl(rx_reg);
608 dev_vdbg(&spi->dev, "read-%d %08x\n",
609 word_len, *(rx - 1));
610 if (mcspi_wait_for_reg_bit(chstat_reg,
611 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
612 dev_err(&spi->dev,
613 "RXS timed out\n");
614 goto out;
615 }
616 c = 0;
617 } else if (c == 0 && tx == NULL) {
618 omap2_mcspi_set_enable(spi, 0);
619 }
620
621 *rx++ = __raw_readl(rx_reg);
622 dev_vdbg(&spi->dev, "read-%d %08x\n",
623 word_len, *(rx - 1));
624 }
625 } while (c >= 4);
626 }
627
628 /* for TX_ONLY mode, be sure all words have shifted out */
629 if (xfer->rx_buf == NULL) {
630 if (mcspi_wait_for_reg_bit(chstat_reg,
631 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
632 dev_err(&spi->dev, "TXS timed out\n");
633 } else if (mcspi_wait_for_reg_bit(chstat_reg,
634 OMAP2_MCSPI_CHSTAT_EOT) < 0)
635 dev_err(&spi->dev, "EOT timed out\n");
636
637 /* disable chan to purge rx datas received in TX_ONLY transfer,
638 * otherwise these rx datas will affect the direct following
639 * RX_ONLY transfer.
640 */
641 omap2_mcspi_set_enable(spi, 0);
642 }
643out:
644 omap2_mcspi_set_enable(spi, 1);
645 return count - c;
646}
647
648static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
649{
650 u32 div;
651
652 for (div = 0; div < 15; div++)
653 if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
654 return div;
655
656 return 15;
657}
658
659/* called only when no transfer is active to this device */
660static int omap2_mcspi_setup_transfer(struct spi_device *spi,
661 struct spi_transfer *t)
662{
663 struct omap2_mcspi_cs *cs = spi->controller_state;
664 struct omap2_mcspi *mcspi;
665 struct spi_master *spi_cntrl;
666 u32 l = 0, div = 0;
667 u8 word_len = spi->bits_per_word;
668 u32 speed_hz = spi->max_speed_hz;
669
670 mcspi = spi_master_get_devdata(spi->master);
671 spi_cntrl = mcspi->master;
672
673 if (t != NULL && t->bits_per_word)
674 word_len = t->bits_per_word;
675
676 cs->word_len = word_len;
677
678 if (t && t->speed_hz)
679 speed_hz = t->speed_hz;
680
681 speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
682 div = omap2_mcspi_calc_divisor(speed_hz);
683
684 l = mcspi_cached_chconf0(spi);
685
686 /* standard 4-wire master mode: SCK, MOSI/out, MISO/in, nCS
687 * REVISIT: this controller could support SPI_3WIRE mode.
688 */
689 l &= ~(OMAP2_MCSPI_CHCONF_IS|OMAP2_MCSPI_CHCONF_DPE1);
690 l |= OMAP2_MCSPI_CHCONF_DPE0;
691
692 /* wordlength */
693 l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
694 l |= (word_len - 1) << 7;
695
696 /* set chipselect polarity; manage with FORCE */
697 if (!(spi->mode & SPI_CS_HIGH))
698 l |= OMAP2_MCSPI_CHCONF_EPOL; /* active-low; normal */
699 else
700 l &= ~OMAP2_MCSPI_CHCONF_EPOL;
701
702 /* set clock divisor */
703 l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
704 l |= div << 2;
705
706 /* set SPI mode 0..3 */
707 if (spi->mode & SPI_CPOL)
708 l |= OMAP2_MCSPI_CHCONF_POL;
709 else
710 l &= ~OMAP2_MCSPI_CHCONF_POL;
711 if (spi->mode & SPI_CPHA)
712 l |= OMAP2_MCSPI_CHCONF_PHA;
713 else
714 l &= ~OMAP2_MCSPI_CHCONF_PHA;
715
716 mcspi_write_chconf0(spi, l);
717
718 dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
719 OMAP2_MCSPI_MAX_FREQ >> div,
720 (spi->mode & SPI_CPHA) ? "trailing" : "leading",
721 (spi->mode & SPI_CPOL) ? "inverted" : "normal");
722
723 return 0;
724}
725
726static void omap2_mcspi_dma_rx_callback(int lch, u16 ch_status, void *data)
727{
728 struct spi_device *spi = data;
729 struct omap2_mcspi *mcspi;
730 struct omap2_mcspi_dma *mcspi_dma;
731
732 mcspi = spi_master_get_devdata(spi->master);
733 mcspi_dma = &(mcspi->dma_channels[spi->chip_select]);
734
735 complete(&mcspi_dma->dma_rx_completion);
736
737 /* We must disable the DMA RX request */
738 omap2_mcspi_set_dma_req(spi, 1, 0);
739}
740
741static void omap2_mcspi_dma_tx_callback(int lch, u16 ch_status, void *data)
742{
743 struct spi_device *spi = data;
744 struct omap2_mcspi *mcspi;
745 struct omap2_mcspi_dma *mcspi_dma;
746
747 mcspi = spi_master_get_devdata(spi->master);
748 mcspi_dma = &(mcspi->dma_channels[spi->chip_select]);
749
750 complete(&mcspi_dma->dma_tx_completion);
751
752 /* We must disable the DMA TX request */
753 omap2_mcspi_set_dma_req(spi, 0, 0);
754}
755
756static int omap2_mcspi_request_dma(struct spi_device *spi)
757{
758 struct spi_master *master = spi->master;
759 struct omap2_mcspi *mcspi;
760 struct omap2_mcspi_dma *mcspi_dma;
761
762 mcspi = spi_master_get_devdata(master);
763 mcspi_dma = mcspi->dma_channels + spi->chip_select;
764
765 if (omap_request_dma(mcspi_dma->dma_rx_sync_dev, "McSPI RX",
766 omap2_mcspi_dma_rx_callback, spi,
767 &mcspi_dma->dma_rx_channel)) {
768 dev_err(&spi->dev, "no RX DMA channel for McSPI\n");
769 return -EAGAIN;
770 }
771
772 if (omap_request_dma(mcspi_dma->dma_tx_sync_dev, "McSPI TX",
773 omap2_mcspi_dma_tx_callback, spi,
774 &mcspi_dma->dma_tx_channel)) {
775 omap_free_dma(mcspi_dma->dma_rx_channel);
776 mcspi_dma->dma_rx_channel = -1;
777 dev_err(&spi->dev, "no TX DMA channel for McSPI\n");
778 return -EAGAIN;
779 }
780
781 init_completion(&mcspi_dma->dma_rx_completion);
782 init_completion(&mcspi_dma->dma_tx_completion);
783
784 return 0;
785}
786
787static int omap2_mcspi_setup(struct spi_device *spi)
788{
789 int ret;
790 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
791 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
792 struct omap2_mcspi_dma *mcspi_dma;
793 struct omap2_mcspi_cs *cs = spi->controller_state;
794
795 if (spi->bits_per_word < 4 || spi->bits_per_word > 32) {
796 dev_dbg(&spi->dev, "setup: unsupported %d bit words\n",
797 spi->bits_per_word);
798 return -EINVAL;
799 }
800
801 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
802
803 if (!cs) {
804 cs = kzalloc(sizeof *cs, GFP_KERNEL);
805 if (!cs)
806 return -ENOMEM;
807 cs->base = mcspi->base + spi->chip_select * 0x14;
808 cs->phys = mcspi->phys + spi->chip_select * 0x14;
809 cs->chconf0 = 0;
810 spi->controller_state = cs;
811 /* Link this to context save list */
812 list_add_tail(&cs->node, &ctx->cs);
813 }
814
815 if (mcspi_dma->dma_rx_channel == -1
816 || mcspi_dma->dma_tx_channel == -1) {
817 ret = omap2_mcspi_request_dma(spi);
818 if (ret < 0)
819 return ret;
820 }
821
822 ret = omap2_mcspi_enable_clocks(mcspi);
823 if (ret < 0)
824 return ret;
825
826 ret = omap2_mcspi_setup_transfer(spi, NULL);
827 omap2_mcspi_disable_clocks(mcspi);
828
829 return ret;
830}
831
832static void omap2_mcspi_cleanup(struct spi_device *spi)
833{
834 struct omap2_mcspi *mcspi;
835 struct omap2_mcspi_dma *mcspi_dma;
836 struct omap2_mcspi_cs *cs;
837
838 mcspi = spi_master_get_devdata(spi->master);
839
840 if (spi->controller_state) {
841 /* Unlink controller state from context save list */
842 cs = spi->controller_state;
843 list_del(&cs->node);
844
845 kfree(cs);
846 }
847
848 if (spi->chip_select < spi->master->num_chipselect) {
849 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
850
851 if (mcspi_dma->dma_rx_channel != -1) {
852 omap_free_dma(mcspi_dma->dma_rx_channel);
853 mcspi_dma->dma_rx_channel = -1;
854 }
855 if (mcspi_dma->dma_tx_channel != -1) {
856 omap_free_dma(mcspi_dma->dma_tx_channel);
857 mcspi_dma->dma_tx_channel = -1;
858 }
859 }
860}
861
862static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
863{
864
865 /* We only enable one channel at a time -- the one whose message is
866 * -- although this controller would gladly
867 * arbitrate among multiple channels. This corresponds to "single
868 * channel" master mode. As a side effect, we need to manage the
869 * chipselect with the FORCE bit ... CS != channel enable.
870 */
871
872 struct spi_device *spi;
873 struct spi_transfer *t = NULL;
874 int cs_active = 0;
875 struct omap2_mcspi_cs *cs;
876 struct omap2_mcspi_device_config *cd;
877 int par_override = 0;
878 int status = 0;
879 u32 chconf;
880
881 spi = m->spi;
882 cs = spi->controller_state;
883 cd = spi->controller_data;
884
885 omap2_mcspi_set_enable(spi, 1);
886 list_for_each_entry(t, &m->transfers, transfer_list) {
887 if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) {
888 status = -EINVAL;
889 break;
890 }
891 if (par_override || t->speed_hz || t->bits_per_word) {
892 par_override = 1;
893 status = omap2_mcspi_setup_transfer(spi, t);
894 if (status < 0)
895 break;
896 if (!t->speed_hz && !t->bits_per_word)
897 par_override = 0;
898 }
899
900 if (!cs_active) {
901 omap2_mcspi_force_cs(spi, 1);
902 cs_active = 1;
903 }
904
905 chconf = mcspi_cached_chconf0(spi);
906 chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
907 chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
908
909 if (t->tx_buf == NULL)
910 chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
911 else if (t->rx_buf == NULL)
912 chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
913
914 if (cd && cd->turbo_mode && t->tx_buf == NULL) {
915 /* Turbo mode is for more than one word */
916 if (t->len > ((cs->word_len + 7) >> 3))
917 chconf |= OMAP2_MCSPI_CHCONF_TURBO;
918 }
919
920 mcspi_write_chconf0(spi, chconf);
921
922 if (t->len) {
923 unsigned count;
924
925 /* RX_ONLY mode needs dummy data in TX reg */
926 if (t->tx_buf == NULL)
927 __raw_writel(0, cs->base
928 + OMAP2_MCSPI_TX0);
929
930 if (m->is_dma_mapped || t->len >= DMA_MIN_BYTES)
931 count = omap2_mcspi_txrx_dma(spi, t);
932 else
933 count = omap2_mcspi_txrx_pio(spi, t);
934 m->actual_length += count;
935
936 if (count != t->len) {
937 status = -EIO;
938 break;
939 }
940 }
941
942 if (t->delay_usecs)
943 udelay(t->delay_usecs);
944
945 /* ignore the "leave it on after last xfer" hint */
946 if (t->cs_change) {
947 omap2_mcspi_force_cs(spi, 0);
948 cs_active = 0;
949 }
950 }
951 /* Restore defaults if they were overriden */
952 if (par_override) {
953 par_override = 0;
954 status = omap2_mcspi_setup_transfer(spi, NULL);
955 }
956
957 if (cs_active)
958 omap2_mcspi_force_cs(spi, 0);
959
960 omap2_mcspi_set_enable(spi, 0);
961
962 m->status = status;
963
964}
965
966static int omap2_mcspi_transfer_one_message(struct spi_master *master,
967 struct spi_message *m)
968{
969 struct omap2_mcspi *mcspi;
970 struct spi_transfer *t;
971
972 mcspi = spi_master_get_devdata(master);
973 m->actual_length = 0;
974 m->status = 0;
975
976 /* reject invalid messages and transfers */
977 if (list_empty(&m->transfers))
978 return -EINVAL;
979 list_for_each_entry(t, &m->transfers, transfer_list) {
980 const void *tx_buf = t->tx_buf;
981 void *rx_buf = t->rx_buf;
982 unsigned len = t->len;
983
984 if (t->speed_hz > OMAP2_MCSPI_MAX_FREQ
985 || (len && !(rx_buf || tx_buf))
986 || (t->bits_per_word &&
987 ( t->bits_per_word < 4
988 || t->bits_per_word > 32))) {
989 dev_dbg(mcspi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
990 t->speed_hz,
991 len,
992 tx_buf ? "tx" : "",
993 rx_buf ? "rx" : "",
994 t->bits_per_word);
995 return -EINVAL;
996 }
997 if (t->speed_hz && t->speed_hz < (OMAP2_MCSPI_MAX_FREQ >> 15)) {
998 dev_dbg(mcspi->dev, "speed_hz %d below minimum %d Hz\n",
999 t->speed_hz,
1000 OMAP2_MCSPI_MAX_FREQ >> 15);
1001 return -EINVAL;
1002 }
1003
1004 if (m->is_dma_mapped || len < DMA_MIN_BYTES)
1005 continue;
1006
1007 if (tx_buf != NULL) {
1008 t->tx_dma = dma_map_single(mcspi->dev, (void *) tx_buf,
1009 len, DMA_TO_DEVICE);
1010 if (dma_mapping_error(mcspi->dev, t->tx_dma)) {
1011 dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1012 'T', len);
1013 return -EINVAL;
1014 }
1015 }
1016 if (rx_buf != NULL) {
1017 t->rx_dma = dma_map_single(mcspi->dev, rx_buf, t->len,
1018 DMA_FROM_DEVICE);
1019 if (dma_mapping_error(mcspi->dev, t->rx_dma)) {
1020 dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1021 'R', len);
1022 if (tx_buf != NULL)
1023 dma_unmap_single(mcspi->dev, t->tx_dma,
1024 len, DMA_TO_DEVICE);
1025 return -EINVAL;
1026 }
1027 }
1028 }
1029
1030 omap2_mcspi_work(mcspi, m);
1031 spi_finalize_current_message(master);
1032 return 0;
1033}
1034
1035static int __init omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
1036{
1037 struct spi_master *master = mcspi->master;
1038 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1039 int ret = 0;
1040
1041 ret = omap2_mcspi_enable_clocks(mcspi);
1042 if (ret < 0)
1043 return ret;
1044
1045 mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1046 OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1047 ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1048
1049 omap2_mcspi_set_master_mode(master);
1050 omap2_mcspi_disable_clocks(mcspi);
1051 return 0;
1052}
1053
1054static int omap_mcspi_runtime_resume(struct device *dev)
1055{
1056 struct omap2_mcspi *mcspi;
1057 struct spi_master *master;
1058
1059 master = dev_get_drvdata(dev);
1060 mcspi = spi_master_get_devdata(master);
1061 omap2_mcspi_restore_ctx(mcspi);
1062
1063 return 0;
1064}
1065
1066static struct omap2_mcspi_platform_config omap2_pdata = {
1067 .regs_offset = 0,
1068};
1069
1070static struct omap2_mcspi_platform_config omap4_pdata = {
1071 .regs_offset = OMAP4_MCSPI_REG_OFFSET,
1072};
1073
1074static const struct of_device_id omap_mcspi_of_match[] = {
1075 {
1076 .compatible = "ti,omap2-mcspi",
1077 .data = &omap2_pdata,
1078 },
1079 {
1080 .compatible = "ti,omap4-mcspi",
1081 .data = &omap4_pdata,
1082 },
1083 { },
1084};
1085MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1086
1087static int __devinit omap2_mcspi_probe(struct platform_device *pdev)
1088{
1089 struct spi_master *master;
1090 struct omap2_mcspi_platform_config *pdata;
1091 struct omap2_mcspi *mcspi;
1092 struct resource *r;
1093 int status = 0, i;
1094 u32 regs_offset = 0;
1095 static int bus_num = 1;
1096 struct device_node *node = pdev->dev.of_node;
1097 const struct of_device_id *match;
1098
1099 master = spi_alloc_master(&pdev->dev, sizeof *mcspi);
1100 if (master == NULL) {
1101 dev_dbg(&pdev->dev, "master allocation failed\n");
1102 return -ENOMEM;
1103 }
1104
1105 /* the spi->mode bits understood by this driver: */
1106 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1107
1108 master->setup = omap2_mcspi_setup;
1109 master->prepare_transfer_hardware = omap2_prepare_transfer;
1110 master->unprepare_transfer_hardware = omap2_unprepare_transfer;
1111 master->transfer_one_message = omap2_mcspi_transfer_one_message;
1112 master->cleanup = omap2_mcspi_cleanup;
1113 master->dev.of_node = node;
1114
1115 match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1116 if (match) {
1117 u32 num_cs = 1; /* default number of chipselect */
1118 pdata = match->data;
1119
1120 of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1121 master->num_chipselect = num_cs;
1122 master->bus_num = bus_num++;
1123 } else {
1124 pdata = pdev->dev.platform_data;
1125 master->num_chipselect = pdata->num_cs;
1126 if (pdev->id != -1)
1127 master->bus_num = pdev->id;
1128 }
1129 regs_offset = pdata->regs_offset;
1130
1131 dev_set_drvdata(&pdev->dev, master);
1132
1133 mcspi = spi_master_get_devdata(master);
1134 mcspi->master = master;
1135
1136 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1137 if (r == NULL) {
1138 status = -ENODEV;
1139 goto free_master;
1140 }
1141
1142 r->start += regs_offset;
1143 r->end += regs_offset;
1144 mcspi->phys = r->start;
1145
1146 mcspi->base = devm_request_and_ioremap(&pdev->dev, r);
1147 if (!mcspi->base) {
1148 dev_dbg(&pdev->dev, "can't ioremap MCSPI\n");
1149 status = -ENOMEM;
1150 goto free_master;
1151 }
1152
1153 mcspi->dev = &pdev->dev;
1154
1155 INIT_LIST_HEAD(&mcspi->ctx.cs);
1156
1157 mcspi->dma_channels = kcalloc(master->num_chipselect,
1158 sizeof(struct omap2_mcspi_dma),
1159 GFP_KERNEL);
1160
1161 if (mcspi->dma_channels == NULL)
1162 goto free_master;
1163
1164 for (i = 0; i < master->num_chipselect; i++) {
1165 char dma_ch_name[14];
1166 struct resource *dma_res;
1167
1168 sprintf(dma_ch_name, "rx%d", i);
1169 dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA,
1170 dma_ch_name);
1171 if (!dma_res) {
1172 dev_dbg(&pdev->dev, "cannot get DMA RX channel\n");
1173 status = -ENODEV;
1174 break;
1175 }
1176
1177 mcspi->dma_channels[i].dma_rx_channel = -1;
1178 mcspi->dma_channels[i].dma_rx_sync_dev = dma_res->start;
1179 sprintf(dma_ch_name, "tx%d", i);
1180 dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA,
1181 dma_ch_name);
1182 if (!dma_res) {
1183 dev_dbg(&pdev->dev, "cannot get DMA TX channel\n");
1184 status = -ENODEV;
1185 break;
1186 }
1187
1188 mcspi->dma_channels[i].dma_tx_channel = -1;
1189 mcspi->dma_channels[i].dma_tx_sync_dev = dma_res->start;
1190 }
1191
1192 if (status < 0)
1193 goto dma_chnl_free;
1194
1195 pm_runtime_use_autosuspend(&pdev->dev);
1196 pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1197 pm_runtime_enable(&pdev->dev);
1198
1199 if (status || omap2_mcspi_master_setup(mcspi) < 0)
1200 goto disable_pm;
1201
1202 status = spi_register_master(master);
1203 if (status < 0)
1204 goto err_spi_register;
1205
1206 return status;
1207
1208err_spi_register:
1209 spi_master_put(master);
1210disable_pm:
1211 pm_runtime_disable(&pdev->dev);
1212dma_chnl_free:
1213 kfree(mcspi->dma_channels);
1214free_master:
1215 kfree(master);
1216 platform_set_drvdata(pdev, NULL);
1217 return status;
1218}
1219
1220static int __devexit omap2_mcspi_remove(struct platform_device *pdev)
1221{
1222 struct spi_master *master;
1223 struct omap2_mcspi *mcspi;
1224 struct omap2_mcspi_dma *dma_channels;
1225
1226 master = dev_get_drvdata(&pdev->dev);
1227 mcspi = spi_master_get_devdata(master);
1228 dma_channels = mcspi->dma_channels;
1229
1230 omap2_mcspi_disable_clocks(mcspi);
1231 pm_runtime_disable(&pdev->dev);
1232
1233 spi_unregister_master(master);
1234 kfree(dma_channels);
1235 platform_set_drvdata(pdev, NULL);
1236
1237 return 0;
1238}
1239
1240/* work with hotplug and coldplug */
1241MODULE_ALIAS("platform:omap2_mcspi");
1242
1243#ifdef CONFIG_SUSPEND
1244/*
1245 * When SPI wake up from off-mode, CS is in activate state. If it was in
1246 * unactive state when driver was suspend, then force it to unactive state at
1247 * wake up.
1248 */
1249static int omap2_mcspi_resume(struct device *dev)
1250{
1251 struct spi_master *master = dev_get_drvdata(dev);
1252 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1253 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1254 struct omap2_mcspi_cs *cs;
1255
1256 omap2_mcspi_enable_clocks(mcspi);
1257 list_for_each_entry(cs, &ctx->cs, node) {
1258 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1259 /*
1260 * We need to toggle CS state for OMAP take this
1261 * change in account.
1262 */
1263 MOD_REG_BIT(cs->chconf0, OMAP2_MCSPI_CHCONF_FORCE, 1);
1264 __raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1265 MOD_REG_BIT(cs->chconf0, OMAP2_MCSPI_CHCONF_FORCE, 0);
1266 __raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1267 }
1268 }
1269 omap2_mcspi_disable_clocks(mcspi);
1270 return 0;
1271}
1272#else
1273#define omap2_mcspi_resume NULL
1274#endif
1275
1276static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1277 .resume = omap2_mcspi_resume,
1278 .runtime_resume = omap_mcspi_runtime_resume,
1279};
1280
1281static struct platform_driver omap2_mcspi_driver = {
1282 .driver = {
1283 .name = "omap2_mcspi",
1284 .owner = THIS_MODULE,
1285 .pm = &omap2_mcspi_pm_ops,
1286 .of_match_table = omap_mcspi_of_match,
1287 },
1288 .probe = omap2_mcspi_probe,
1289 .remove = __devexit_p(omap2_mcspi_remove),
1290};
1291
1292module_platform_driver(omap2_mcspi_driver);
1293MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * OMAP2 McSPI controller driver
4 *
5 * Copyright (C) 2005, 2006 Nokia Corporation
6 * Author: Samuel Ortiz <samuel.ortiz@nokia.com> and
7 * Juha Yrj�l� <juha.yrjola@nokia.com>
8 */
9
10#include <linux/kernel.h>
11#include <linux/interrupt.h>
12#include <linux/module.h>
13#include <linux/device.h>
14#include <linux/delay.h>
15#include <linux/dma-mapping.h>
16#include <linux/dmaengine.h>
17#include <linux/pinctrl/consumer.h>
18#include <linux/platform_device.h>
19#include <linux/err.h>
20#include <linux/clk.h>
21#include <linux/io.h>
22#include <linux/slab.h>
23#include <linux/pm_runtime.h>
24#include <linux/of.h>
25#include <linux/of_device.h>
26#include <linux/gcd.h>
27#include <linux/iopoll.h>
28
29#include <linux/spi/spi.h>
30#include <linux/gpio.h>
31
32#include <linux/platform_data/spi-omap2-mcspi.h>
33
34#define OMAP2_MCSPI_MAX_FREQ 48000000
35#define OMAP2_MCSPI_MAX_DIVIDER 4096
36#define OMAP2_MCSPI_MAX_FIFODEPTH 64
37#define OMAP2_MCSPI_MAX_FIFOWCNT 0xFFFF
38#define SPI_AUTOSUSPEND_TIMEOUT 2000
39
40#define OMAP2_MCSPI_REVISION 0x00
41#define OMAP2_MCSPI_SYSSTATUS 0x14
42#define OMAP2_MCSPI_IRQSTATUS 0x18
43#define OMAP2_MCSPI_IRQENABLE 0x1c
44#define OMAP2_MCSPI_WAKEUPENABLE 0x20
45#define OMAP2_MCSPI_SYST 0x24
46#define OMAP2_MCSPI_MODULCTRL 0x28
47#define OMAP2_MCSPI_XFERLEVEL 0x7c
48
49/* per-channel banks, 0x14 bytes each, first is: */
50#define OMAP2_MCSPI_CHCONF0 0x2c
51#define OMAP2_MCSPI_CHSTAT0 0x30
52#define OMAP2_MCSPI_CHCTRL0 0x34
53#define OMAP2_MCSPI_TX0 0x38
54#define OMAP2_MCSPI_RX0 0x3c
55
56/* per-register bitmasks: */
57#define OMAP2_MCSPI_IRQSTATUS_EOW BIT(17)
58
59#define OMAP2_MCSPI_MODULCTRL_SINGLE BIT(0)
60#define OMAP2_MCSPI_MODULCTRL_MS BIT(2)
61#define OMAP2_MCSPI_MODULCTRL_STEST BIT(3)
62
63#define OMAP2_MCSPI_CHCONF_PHA BIT(0)
64#define OMAP2_MCSPI_CHCONF_POL BIT(1)
65#define OMAP2_MCSPI_CHCONF_CLKD_MASK (0x0f << 2)
66#define OMAP2_MCSPI_CHCONF_EPOL BIT(6)
67#define OMAP2_MCSPI_CHCONF_WL_MASK (0x1f << 7)
68#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY BIT(12)
69#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY BIT(13)
70#define OMAP2_MCSPI_CHCONF_TRM_MASK (0x03 << 12)
71#define OMAP2_MCSPI_CHCONF_DMAW BIT(14)
72#define OMAP2_MCSPI_CHCONF_DMAR BIT(15)
73#define OMAP2_MCSPI_CHCONF_DPE0 BIT(16)
74#define OMAP2_MCSPI_CHCONF_DPE1 BIT(17)
75#define OMAP2_MCSPI_CHCONF_IS BIT(18)
76#define OMAP2_MCSPI_CHCONF_TURBO BIT(19)
77#define OMAP2_MCSPI_CHCONF_FORCE BIT(20)
78#define OMAP2_MCSPI_CHCONF_FFET BIT(27)
79#define OMAP2_MCSPI_CHCONF_FFER BIT(28)
80#define OMAP2_MCSPI_CHCONF_CLKG BIT(29)
81
82#define OMAP2_MCSPI_CHSTAT_RXS BIT(0)
83#define OMAP2_MCSPI_CHSTAT_TXS BIT(1)
84#define OMAP2_MCSPI_CHSTAT_EOT BIT(2)
85#define OMAP2_MCSPI_CHSTAT_TXFFE BIT(3)
86
87#define OMAP2_MCSPI_CHCTRL_EN BIT(0)
88#define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK (0xff << 8)
89
90#define OMAP2_MCSPI_WAKEUPENABLE_WKEN BIT(0)
91
92/* We have 2 DMA channels per CS, one for RX and one for TX */
93struct omap2_mcspi_dma {
94 struct dma_chan *dma_tx;
95 struct dma_chan *dma_rx;
96
97 struct completion dma_tx_completion;
98 struct completion dma_rx_completion;
99
100 char dma_rx_ch_name[14];
101 char dma_tx_ch_name[14];
102};
103
104/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
105 * cache operations; better heuristics consider wordsize and bitrate.
106 */
107#define DMA_MIN_BYTES 160
108
109
110/*
111 * Used for context save and restore, structure members to be updated whenever
112 * corresponding registers are modified.
113 */
114struct omap2_mcspi_regs {
115 u32 modulctrl;
116 u32 wakeupenable;
117 struct list_head cs;
118};
119
120struct omap2_mcspi {
121 struct completion txdone;
122 struct spi_master *master;
123 /* Virtual base address of the controller */
124 void __iomem *base;
125 unsigned long phys;
126 /* SPI1 has 4 channels, while SPI2 has 2 */
127 struct omap2_mcspi_dma *dma_channels;
128 struct device *dev;
129 struct omap2_mcspi_regs ctx;
130 int fifo_depth;
131 bool slave_aborted;
132 unsigned int pin_dir:1;
133};
134
135struct omap2_mcspi_cs {
136 void __iomem *base;
137 unsigned long phys;
138 int word_len;
139 u16 mode;
140 struct list_head node;
141 /* Context save and restore shadow register */
142 u32 chconf0, chctrl0;
143};
144
145static inline void mcspi_write_reg(struct spi_master *master,
146 int idx, u32 val)
147{
148 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
149
150 writel_relaxed(val, mcspi->base + idx);
151}
152
153static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
154{
155 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
156
157 return readl_relaxed(mcspi->base + idx);
158}
159
160static inline void mcspi_write_cs_reg(const struct spi_device *spi,
161 int idx, u32 val)
162{
163 struct omap2_mcspi_cs *cs = spi->controller_state;
164
165 writel_relaxed(val, cs->base + idx);
166}
167
168static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
169{
170 struct omap2_mcspi_cs *cs = spi->controller_state;
171
172 return readl_relaxed(cs->base + idx);
173}
174
175static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
176{
177 struct omap2_mcspi_cs *cs = spi->controller_state;
178
179 return cs->chconf0;
180}
181
182static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
183{
184 struct omap2_mcspi_cs *cs = spi->controller_state;
185
186 cs->chconf0 = val;
187 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
188 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
189}
190
191static inline int mcspi_bytes_per_word(int word_len)
192{
193 if (word_len <= 8)
194 return 1;
195 else if (word_len <= 16)
196 return 2;
197 else /* word_len <= 32 */
198 return 4;
199}
200
201static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
202 int is_read, int enable)
203{
204 u32 l, rw;
205
206 l = mcspi_cached_chconf0(spi);
207
208 if (is_read) /* 1 is read, 0 write */
209 rw = OMAP2_MCSPI_CHCONF_DMAR;
210 else
211 rw = OMAP2_MCSPI_CHCONF_DMAW;
212
213 if (enable)
214 l |= rw;
215 else
216 l &= ~rw;
217
218 mcspi_write_chconf0(spi, l);
219}
220
221static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
222{
223 struct omap2_mcspi_cs *cs = spi->controller_state;
224 u32 l;
225
226 l = cs->chctrl0;
227 if (enable)
228 l |= OMAP2_MCSPI_CHCTRL_EN;
229 else
230 l &= ~OMAP2_MCSPI_CHCTRL_EN;
231 cs->chctrl0 = l;
232 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
233 /* Flash post-writes */
234 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
235}
236
237static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable)
238{
239 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
240 u32 l;
241
242 /* The controller handles the inverted chip selects
243 * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert
244 * the inversion from the core spi_set_cs function.
245 */
246 if (spi->mode & SPI_CS_HIGH)
247 enable = !enable;
248
249 if (spi->controller_state) {
250 int err = pm_runtime_get_sync(mcspi->dev);
251 if (err < 0) {
252 pm_runtime_put_noidle(mcspi->dev);
253 dev_err(mcspi->dev, "failed to get sync: %d\n", err);
254 return;
255 }
256
257 l = mcspi_cached_chconf0(spi);
258
259 if (enable)
260 l &= ~OMAP2_MCSPI_CHCONF_FORCE;
261 else
262 l |= OMAP2_MCSPI_CHCONF_FORCE;
263
264 mcspi_write_chconf0(spi, l);
265
266 pm_runtime_mark_last_busy(mcspi->dev);
267 pm_runtime_put_autosuspend(mcspi->dev);
268 }
269}
270
271static void omap2_mcspi_set_mode(struct spi_master *master)
272{
273 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
274 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
275 u32 l;
276
277 /*
278 * Choose master or slave mode
279 */
280 l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
281 l &= ~(OMAP2_MCSPI_MODULCTRL_STEST);
282 if (spi_controller_is_slave(master)) {
283 l |= (OMAP2_MCSPI_MODULCTRL_MS);
284 } else {
285 l &= ~(OMAP2_MCSPI_MODULCTRL_MS);
286 l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
287 }
288 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
289
290 ctx->modulctrl = l;
291}
292
293static void omap2_mcspi_set_fifo(const struct spi_device *spi,
294 struct spi_transfer *t, int enable)
295{
296 struct spi_master *master = spi->master;
297 struct omap2_mcspi_cs *cs = spi->controller_state;
298 struct omap2_mcspi *mcspi;
299 unsigned int wcnt;
300 int max_fifo_depth, bytes_per_word;
301 u32 chconf, xferlevel;
302
303 mcspi = spi_master_get_devdata(master);
304
305 chconf = mcspi_cached_chconf0(spi);
306 if (enable) {
307 bytes_per_word = mcspi_bytes_per_word(cs->word_len);
308 if (t->len % bytes_per_word != 0)
309 goto disable_fifo;
310
311 if (t->rx_buf != NULL && t->tx_buf != NULL)
312 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
313 else
314 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
315
316 wcnt = t->len / bytes_per_word;
317 if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
318 goto disable_fifo;
319
320 xferlevel = wcnt << 16;
321 if (t->rx_buf != NULL) {
322 chconf |= OMAP2_MCSPI_CHCONF_FFER;
323 xferlevel |= (bytes_per_word - 1) << 8;
324 }
325
326 if (t->tx_buf != NULL) {
327 chconf |= OMAP2_MCSPI_CHCONF_FFET;
328 xferlevel |= bytes_per_word - 1;
329 }
330
331 mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel);
332 mcspi_write_chconf0(spi, chconf);
333 mcspi->fifo_depth = max_fifo_depth;
334
335 return;
336 }
337
338disable_fifo:
339 if (t->rx_buf != NULL)
340 chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
341
342 if (t->tx_buf != NULL)
343 chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
344
345 mcspi_write_chconf0(spi, chconf);
346 mcspi->fifo_depth = 0;
347}
348
349static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
350{
351 u32 val;
352
353 return readl_poll_timeout(reg, val, val & bit, 1, MSEC_PER_SEC);
354}
355
356static int mcspi_wait_for_completion(struct omap2_mcspi *mcspi,
357 struct completion *x)
358{
359 if (spi_controller_is_slave(mcspi->master)) {
360 if (wait_for_completion_interruptible(x) ||
361 mcspi->slave_aborted)
362 return -EINTR;
363 } else {
364 wait_for_completion(x);
365 }
366
367 return 0;
368}
369
370static void omap2_mcspi_rx_callback(void *data)
371{
372 struct spi_device *spi = data;
373 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
374 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
375
376 /* We must disable the DMA RX request */
377 omap2_mcspi_set_dma_req(spi, 1, 0);
378
379 complete(&mcspi_dma->dma_rx_completion);
380}
381
382static void omap2_mcspi_tx_callback(void *data)
383{
384 struct spi_device *spi = data;
385 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
386 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
387
388 /* We must disable the DMA TX request */
389 omap2_mcspi_set_dma_req(spi, 0, 0);
390
391 complete(&mcspi_dma->dma_tx_completion);
392}
393
394static void omap2_mcspi_tx_dma(struct spi_device *spi,
395 struct spi_transfer *xfer,
396 struct dma_slave_config cfg)
397{
398 struct omap2_mcspi *mcspi;
399 struct omap2_mcspi_dma *mcspi_dma;
400
401 mcspi = spi_master_get_devdata(spi->master);
402 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
403
404 if (mcspi_dma->dma_tx) {
405 struct dma_async_tx_descriptor *tx;
406
407 dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
408
409 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, xfer->tx_sg.sgl,
410 xfer->tx_sg.nents,
411 DMA_MEM_TO_DEV,
412 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
413 if (tx) {
414 tx->callback = omap2_mcspi_tx_callback;
415 tx->callback_param = spi;
416 dmaengine_submit(tx);
417 } else {
418 /* FIXME: fall back to PIO? */
419 }
420 }
421 dma_async_issue_pending(mcspi_dma->dma_tx);
422 omap2_mcspi_set_dma_req(spi, 0, 1);
423
424}
425
426static unsigned
427omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
428 struct dma_slave_config cfg,
429 unsigned es)
430{
431 struct omap2_mcspi *mcspi;
432 struct omap2_mcspi_dma *mcspi_dma;
433 unsigned int count, transfer_reduction = 0;
434 struct scatterlist *sg_out[2];
435 int nb_sizes = 0, out_mapped_nents[2], ret, x;
436 size_t sizes[2];
437 u32 l;
438 int elements = 0;
439 int word_len, element_count;
440 struct omap2_mcspi_cs *cs = spi->controller_state;
441 void __iomem *chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
442
443 mcspi = spi_master_get_devdata(spi->master);
444 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
445 count = xfer->len;
446
447 /*
448 * In the "End-of-Transfer Procedure" section for DMA RX in OMAP35x TRM
449 * it mentions reducing DMA transfer length by one element in master
450 * normal mode.
451 */
452 if (mcspi->fifo_depth == 0)
453 transfer_reduction = es;
454
455 word_len = cs->word_len;
456 l = mcspi_cached_chconf0(spi);
457
458 if (word_len <= 8)
459 element_count = count;
460 else if (word_len <= 16)
461 element_count = count >> 1;
462 else /* word_len <= 32 */
463 element_count = count >> 2;
464
465 if (mcspi_dma->dma_rx) {
466 struct dma_async_tx_descriptor *tx;
467
468 dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
469
470 /*
471 * Reduce DMA transfer length by one more if McSPI is
472 * configured in turbo mode.
473 */
474 if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
475 transfer_reduction += es;
476
477 if (transfer_reduction) {
478 /* Split sgl into two. The second sgl won't be used. */
479 sizes[0] = count - transfer_reduction;
480 sizes[1] = transfer_reduction;
481 nb_sizes = 2;
482 } else {
483 /*
484 * Don't bother splitting the sgl. This essentially
485 * clones the original sgl.
486 */
487 sizes[0] = count;
488 nb_sizes = 1;
489 }
490
491 ret = sg_split(xfer->rx_sg.sgl, xfer->rx_sg.nents,
492 0, nb_sizes,
493 sizes,
494 sg_out, out_mapped_nents,
495 GFP_KERNEL);
496
497 if (ret < 0) {
498 dev_err(&spi->dev, "sg_split failed\n");
499 return 0;
500 }
501
502 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx,
503 sg_out[0],
504 out_mapped_nents[0],
505 DMA_DEV_TO_MEM,
506 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
507 if (tx) {
508 tx->callback = omap2_mcspi_rx_callback;
509 tx->callback_param = spi;
510 dmaengine_submit(tx);
511 } else {
512 /* FIXME: fall back to PIO? */
513 }
514 }
515
516 dma_async_issue_pending(mcspi_dma->dma_rx);
517 omap2_mcspi_set_dma_req(spi, 1, 1);
518
519 ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_rx_completion);
520 if (ret || mcspi->slave_aborted) {
521 dmaengine_terminate_sync(mcspi_dma->dma_rx);
522 omap2_mcspi_set_dma_req(spi, 1, 0);
523 return 0;
524 }
525
526 for (x = 0; x < nb_sizes; x++)
527 kfree(sg_out[x]);
528
529 if (mcspi->fifo_depth > 0)
530 return count;
531
532 /*
533 * Due to the DMA transfer length reduction the missing bytes must
534 * be read manually to receive all of the expected data.
535 */
536 omap2_mcspi_set_enable(spi, 0);
537
538 elements = element_count - 1;
539
540 if (l & OMAP2_MCSPI_CHCONF_TURBO) {
541 elements--;
542
543 if (!mcspi_wait_for_reg_bit(chstat_reg,
544 OMAP2_MCSPI_CHSTAT_RXS)) {
545 u32 w;
546
547 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
548 if (word_len <= 8)
549 ((u8 *)xfer->rx_buf)[elements++] = w;
550 else if (word_len <= 16)
551 ((u16 *)xfer->rx_buf)[elements++] = w;
552 else /* word_len <= 32 */
553 ((u32 *)xfer->rx_buf)[elements++] = w;
554 } else {
555 int bytes_per_word = mcspi_bytes_per_word(word_len);
556 dev_err(&spi->dev, "DMA RX penultimate word empty\n");
557 count -= (bytes_per_word << 1);
558 omap2_mcspi_set_enable(spi, 1);
559 return count;
560 }
561 }
562 if (!mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS)) {
563 u32 w;
564
565 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
566 if (word_len <= 8)
567 ((u8 *)xfer->rx_buf)[elements] = w;
568 else if (word_len <= 16)
569 ((u16 *)xfer->rx_buf)[elements] = w;
570 else /* word_len <= 32 */
571 ((u32 *)xfer->rx_buf)[elements] = w;
572 } else {
573 dev_err(&spi->dev, "DMA RX last word empty\n");
574 count -= mcspi_bytes_per_word(word_len);
575 }
576 omap2_mcspi_set_enable(spi, 1);
577 return count;
578}
579
580static unsigned
581omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
582{
583 struct omap2_mcspi *mcspi;
584 struct omap2_mcspi_cs *cs = spi->controller_state;
585 struct omap2_mcspi_dma *mcspi_dma;
586 unsigned int count;
587 u8 *rx;
588 const u8 *tx;
589 struct dma_slave_config cfg;
590 enum dma_slave_buswidth width;
591 unsigned es;
592 void __iomem *chstat_reg;
593 void __iomem *irqstat_reg;
594 int wait_res;
595
596 mcspi = spi_master_get_devdata(spi->master);
597 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
598
599 if (cs->word_len <= 8) {
600 width = DMA_SLAVE_BUSWIDTH_1_BYTE;
601 es = 1;
602 } else if (cs->word_len <= 16) {
603 width = DMA_SLAVE_BUSWIDTH_2_BYTES;
604 es = 2;
605 } else {
606 width = DMA_SLAVE_BUSWIDTH_4_BYTES;
607 es = 4;
608 }
609
610 count = xfer->len;
611
612 memset(&cfg, 0, sizeof(cfg));
613 cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
614 cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
615 cfg.src_addr_width = width;
616 cfg.dst_addr_width = width;
617 cfg.src_maxburst = 1;
618 cfg.dst_maxburst = 1;
619
620 rx = xfer->rx_buf;
621 tx = xfer->tx_buf;
622
623 mcspi->slave_aborted = false;
624 reinit_completion(&mcspi_dma->dma_tx_completion);
625 reinit_completion(&mcspi_dma->dma_rx_completion);
626 reinit_completion(&mcspi->txdone);
627 if (tx) {
628 /* Enable EOW IRQ to know end of tx in slave mode */
629 if (spi_controller_is_slave(spi->master))
630 mcspi_write_reg(spi->master,
631 OMAP2_MCSPI_IRQENABLE,
632 OMAP2_MCSPI_IRQSTATUS_EOW);
633 omap2_mcspi_tx_dma(spi, xfer, cfg);
634 }
635
636 if (rx != NULL)
637 count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
638
639 if (tx != NULL) {
640 int ret;
641
642 ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_tx_completion);
643 if (ret || mcspi->slave_aborted) {
644 dmaengine_terminate_sync(mcspi_dma->dma_tx);
645 omap2_mcspi_set_dma_req(spi, 0, 0);
646 return 0;
647 }
648
649 if (spi_controller_is_slave(mcspi->master)) {
650 ret = mcspi_wait_for_completion(mcspi, &mcspi->txdone);
651 if (ret || mcspi->slave_aborted)
652 return 0;
653 }
654
655 if (mcspi->fifo_depth > 0) {
656 irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
657
658 if (mcspi_wait_for_reg_bit(irqstat_reg,
659 OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
660 dev_err(&spi->dev, "EOW timed out\n");
661
662 mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
663 OMAP2_MCSPI_IRQSTATUS_EOW);
664 }
665
666 /* for TX_ONLY mode, be sure all words have shifted out */
667 if (rx == NULL) {
668 chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
669 if (mcspi->fifo_depth > 0) {
670 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
671 OMAP2_MCSPI_CHSTAT_TXFFE);
672 if (wait_res < 0)
673 dev_err(&spi->dev, "TXFFE timed out\n");
674 } else {
675 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
676 OMAP2_MCSPI_CHSTAT_TXS);
677 if (wait_res < 0)
678 dev_err(&spi->dev, "TXS timed out\n");
679 }
680 if (wait_res >= 0 &&
681 (mcspi_wait_for_reg_bit(chstat_reg,
682 OMAP2_MCSPI_CHSTAT_EOT) < 0))
683 dev_err(&spi->dev, "EOT timed out\n");
684 }
685 }
686 return count;
687}
688
689static unsigned
690omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
691{
692 struct omap2_mcspi_cs *cs = spi->controller_state;
693 unsigned int count, c;
694 u32 l;
695 void __iomem *base = cs->base;
696 void __iomem *tx_reg;
697 void __iomem *rx_reg;
698 void __iomem *chstat_reg;
699 int word_len;
700
701 count = xfer->len;
702 c = count;
703 word_len = cs->word_len;
704
705 l = mcspi_cached_chconf0(spi);
706
707 /* We store the pre-calculated register addresses on stack to speed
708 * up the transfer loop. */
709 tx_reg = base + OMAP2_MCSPI_TX0;
710 rx_reg = base + OMAP2_MCSPI_RX0;
711 chstat_reg = base + OMAP2_MCSPI_CHSTAT0;
712
713 if (c < (word_len>>3))
714 return 0;
715
716 if (word_len <= 8) {
717 u8 *rx;
718 const u8 *tx;
719
720 rx = xfer->rx_buf;
721 tx = xfer->tx_buf;
722
723 do {
724 c -= 1;
725 if (tx != NULL) {
726 if (mcspi_wait_for_reg_bit(chstat_reg,
727 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
728 dev_err(&spi->dev, "TXS timed out\n");
729 goto out;
730 }
731 dev_vdbg(&spi->dev, "write-%d %02x\n",
732 word_len, *tx);
733 writel_relaxed(*tx++, tx_reg);
734 }
735 if (rx != NULL) {
736 if (mcspi_wait_for_reg_bit(chstat_reg,
737 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
738 dev_err(&spi->dev, "RXS timed out\n");
739 goto out;
740 }
741
742 if (c == 1 && tx == NULL &&
743 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
744 omap2_mcspi_set_enable(spi, 0);
745 *rx++ = readl_relaxed(rx_reg);
746 dev_vdbg(&spi->dev, "read-%d %02x\n",
747 word_len, *(rx - 1));
748 if (mcspi_wait_for_reg_bit(chstat_reg,
749 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
750 dev_err(&spi->dev,
751 "RXS timed out\n");
752 goto out;
753 }
754 c = 0;
755 } else if (c == 0 && tx == NULL) {
756 omap2_mcspi_set_enable(spi, 0);
757 }
758
759 *rx++ = readl_relaxed(rx_reg);
760 dev_vdbg(&spi->dev, "read-%d %02x\n",
761 word_len, *(rx - 1));
762 }
763 } while (c);
764 } else if (word_len <= 16) {
765 u16 *rx;
766 const u16 *tx;
767
768 rx = xfer->rx_buf;
769 tx = xfer->tx_buf;
770 do {
771 c -= 2;
772 if (tx != NULL) {
773 if (mcspi_wait_for_reg_bit(chstat_reg,
774 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
775 dev_err(&spi->dev, "TXS timed out\n");
776 goto out;
777 }
778 dev_vdbg(&spi->dev, "write-%d %04x\n",
779 word_len, *tx);
780 writel_relaxed(*tx++, tx_reg);
781 }
782 if (rx != NULL) {
783 if (mcspi_wait_for_reg_bit(chstat_reg,
784 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
785 dev_err(&spi->dev, "RXS timed out\n");
786 goto out;
787 }
788
789 if (c == 2 && tx == NULL &&
790 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
791 omap2_mcspi_set_enable(spi, 0);
792 *rx++ = readl_relaxed(rx_reg);
793 dev_vdbg(&spi->dev, "read-%d %04x\n",
794 word_len, *(rx - 1));
795 if (mcspi_wait_for_reg_bit(chstat_reg,
796 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
797 dev_err(&spi->dev,
798 "RXS timed out\n");
799 goto out;
800 }
801 c = 0;
802 } else if (c == 0 && tx == NULL) {
803 omap2_mcspi_set_enable(spi, 0);
804 }
805
806 *rx++ = readl_relaxed(rx_reg);
807 dev_vdbg(&spi->dev, "read-%d %04x\n",
808 word_len, *(rx - 1));
809 }
810 } while (c >= 2);
811 } else if (word_len <= 32) {
812 u32 *rx;
813 const u32 *tx;
814
815 rx = xfer->rx_buf;
816 tx = xfer->tx_buf;
817 do {
818 c -= 4;
819 if (tx != NULL) {
820 if (mcspi_wait_for_reg_bit(chstat_reg,
821 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
822 dev_err(&spi->dev, "TXS timed out\n");
823 goto out;
824 }
825 dev_vdbg(&spi->dev, "write-%d %08x\n",
826 word_len, *tx);
827 writel_relaxed(*tx++, tx_reg);
828 }
829 if (rx != NULL) {
830 if (mcspi_wait_for_reg_bit(chstat_reg,
831 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
832 dev_err(&spi->dev, "RXS timed out\n");
833 goto out;
834 }
835
836 if (c == 4 && tx == NULL &&
837 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
838 omap2_mcspi_set_enable(spi, 0);
839 *rx++ = readl_relaxed(rx_reg);
840 dev_vdbg(&spi->dev, "read-%d %08x\n",
841 word_len, *(rx - 1));
842 if (mcspi_wait_for_reg_bit(chstat_reg,
843 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
844 dev_err(&spi->dev,
845 "RXS timed out\n");
846 goto out;
847 }
848 c = 0;
849 } else if (c == 0 && tx == NULL) {
850 omap2_mcspi_set_enable(spi, 0);
851 }
852
853 *rx++ = readl_relaxed(rx_reg);
854 dev_vdbg(&spi->dev, "read-%d %08x\n",
855 word_len, *(rx - 1));
856 }
857 } while (c >= 4);
858 }
859
860 /* for TX_ONLY mode, be sure all words have shifted out */
861 if (xfer->rx_buf == NULL) {
862 if (mcspi_wait_for_reg_bit(chstat_reg,
863 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
864 dev_err(&spi->dev, "TXS timed out\n");
865 } else if (mcspi_wait_for_reg_bit(chstat_reg,
866 OMAP2_MCSPI_CHSTAT_EOT) < 0)
867 dev_err(&spi->dev, "EOT timed out\n");
868
869 /* disable chan to purge rx datas received in TX_ONLY transfer,
870 * otherwise these rx datas will affect the direct following
871 * RX_ONLY transfer.
872 */
873 omap2_mcspi_set_enable(spi, 0);
874 }
875out:
876 omap2_mcspi_set_enable(spi, 1);
877 return count - c;
878}
879
880static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
881{
882 u32 div;
883
884 for (div = 0; div < 15; div++)
885 if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
886 return div;
887
888 return 15;
889}
890
891/* called only when no transfer is active to this device */
892static int omap2_mcspi_setup_transfer(struct spi_device *spi,
893 struct spi_transfer *t)
894{
895 struct omap2_mcspi_cs *cs = spi->controller_state;
896 struct omap2_mcspi *mcspi;
897 u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
898 u8 word_len = spi->bits_per_word;
899 u32 speed_hz = spi->max_speed_hz;
900
901 mcspi = spi_master_get_devdata(spi->master);
902
903 if (t != NULL && t->bits_per_word)
904 word_len = t->bits_per_word;
905
906 cs->word_len = word_len;
907
908 if (t && t->speed_hz)
909 speed_hz = t->speed_hz;
910
911 speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
912 if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
913 clkd = omap2_mcspi_calc_divisor(speed_hz);
914 speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
915 clkg = 0;
916 } else {
917 div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
918 speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
919 clkd = (div - 1) & 0xf;
920 extclk = (div - 1) >> 4;
921 clkg = OMAP2_MCSPI_CHCONF_CLKG;
922 }
923
924 l = mcspi_cached_chconf0(spi);
925
926 /* standard 4-wire master mode: SCK, MOSI/out, MISO/in, nCS
927 * REVISIT: this controller could support SPI_3WIRE mode.
928 */
929 if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
930 l &= ~OMAP2_MCSPI_CHCONF_IS;
931 l &= ~OMAP2_MCSPI_CHCONF_DPE1;
932 l |= OMAP2_MCSPI_CHCONF_DPE0;
933 } else {
934 l |= OMAP2_MCSPI_CHCONF_IS;
935 l |= OMAP2_MCSPI_CHCONF_DPE1;
936 l &= ~OMAP2_MCSPI_CHCONF_DPE0;
937 }
938
939 /* wordlength */
940 l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
941 l |= (word_len - 1) << 7;
942
943 /* set chipselect polarity; manage with FORCE */
944 if (!(spi->mode & SPI_CS_HIGH))
945 l |= OMAP2_MCSPI_CHCONF_EPOL; /* active-low; normal */
946 else
947 l &= ~OMAP2_MCSPI_CHCONF_EPOL;
948
949 /* set clock divisor */
950 l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
951 l |= clkd << 2;
952
953 /* set clock granularity */
954 l &= ~OMAP2_MCSPI_CHCONF_CLKG;
955 l |= clkg;
956 if (clkg) {
957 cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
958 cs->chctrl0 |= extclk << 8;
959 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
960 }
961
962 /* set SPI mode 0..3 */
963 if (spi->mode & SPI_CPOL)
964 l |= OMAP2_MCSPI_CHCONF_POL;
965 else
966 l &= ~OMAP2_MCSPI_CHCONF_POL;
967 if (spi->mode & SPI_CPHA)
968 l |= OMAP2_MCSPI_CHCONF_PHA;
969 else
970 l &= ~OMAP2_MCSPI_CHCONF_PHA;
971
972 mcspi_write_chconf0(spi, l);
973
974 cs->mode = spi->mode;
975
976 dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
977 speed_hz,
978 (spi->mode & SPI_CPHA) ? "trailing" : "leading",
979 (spi->mode & SPI_CPOL) ? "inverted" : "normal");
980
981 return 0;
982}
983
984/*
985 * Note that we currently allow DMA only if we get a channel
986 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
987 */
988static int omap2_mcspi_request_dma(struct spi_device *spi)
989{
990 struct spi_master *master = spi->master;
991 struct omap2_mcspi *mcspi;
992 struct omap2_mcspi_dma *mcspi_dma;
993 int ret = 0;
994
995 mcspi = spi_master_get_devdata(master);
996 mcspi_dma = mcspi->dma_channels + spi->chip_select;
997
998 init_completion(&mcspi_dma->dma_rx_completion);
999 init_completion(&mcspi_dma->dma_tx_completion);
1000
1001 mcspi_dma->dma_rx = dma_request_chan(&master->dev,
1002 mcspi_dma->dma_rx_ch_name);
1003 if (IS_ERR(mcspi_dma->dma_rx)) {
1004 ret = PTR_ERR(mcspi_dma->dma_rx);
1005 mcspi_dma->dma_rx = NULL;
1006 goto no_dma;
1007 }
1008
1009 mcspi_dma->dma_tx = dma_request_chan(&master->dev,
1010 mcspi_dma->dma_tx_ch_name);
1011 if (IS_ERR(mcspi_dma->dma_tx)) {
1012 ret = PTR_ERR(mcspi_dma->dma_tx);
1013 mcspi_dma->dma_tx = NULL;
1014 dma_release_channel(mcspi_dma->dma_rx);
1015 mcspi_dma->dma_rx = NULL;
1016 }
1017
1018no_dma:
1019 return ret;
1020}
1021
1022static int omap2_mcspi_setup(struct spi_device *spi)
1023{
1024 int ret;
1025 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1026 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1027 struct omap2_mcspi_dma *mcspi_dma;
1028 struct omap2_mcspi_cs *cs = spi->controller_state;
1029
1030 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1031
1032 if (!cs) {
1033 cs = kzalloc(sizeof *cs, GFP_KERNEL);
1034 if (!cs)
1035 return -ENOMEM;
1036 cs->base = mcspi->base + spi->chip_select * 0x14;
1037 cs->phys = mcspi->phys + spi->chip_select * 0x14;
1038 cs->mode = 0;
1039 cs->chconf0 = 0;
1040 cs->chctrl0 = 0;
1041 spi->controller_state = cs;
1042 /* Link this to context save list */
1043 list_add_tail(&cs->node, &ctx->cs);
1044
1045 if (gpio_is_valid(spi->cs_gpio)) {
1046 ret = gpio_request(spi->cs_gpio, dev_name(&spi->dev));
1047 if (ret) {
1048 dev_err(&spi->dev, "failed to request gpio\n");
1049 return ret;
1050 }
1051 gpio_direction_output(spi->cs_gpio,
1052 !(spi->mode & SPI_CS_HIGH));
1053 }
1054 }
1055
1056 if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) {
1057 ret = omap2_mcspi_request_dma(spi);
1058 if (ret)
1059 dev_warn(&spi->dev, "not using DMA for McSPI (%d)\n",
1060 ret);
1061 }
1062
1063 ret = pm_runtime_get_sync(mcspi->dev);
1064 if (ret < 0) {
1065 pm_runtime_put_noidle(mcspi->dev);
1066
1067 return ret;
1068 }
1069
1070 ret = omap2_mcspi_setup_transfer(spi, NULL);
1071 pm_runtime_mark_last_busy(mcspi->dev);
1072 pm_runtime_put_autosuspend(mcspi->dev);
1073
1074 return ret;
1075}
1076
1077static void omap2_mcspi_cleanup(struct spi_device *spi)
1078{
1079 struct omap2_mcspi *mcspi;
1080 struct omap2_mcspi_dma *mcspi_dma;
1081 struct omap2_mcspi_cs *cs;
1082
1083 mcspi = spi_master_get_devdata(spi->master);
1084
1085 if (spi->controller_state) {
1086 /* Unlink controller state from context save list */
1087 cs = spi->controller_state;
1088 list_del(&cs->node);
1089
1090 kfree(cs);
1091 }
1092
1093 if (spi->chip_select < spi->master->num_chipselect) {
1094 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1095
1096 if (mcspi_dma->dma_rx) {
1097 dma_release_channel(mcspi_dma->dma_rx);
1098 mcspi_dma->dma_rx = NULL;
1099 }
1100 if (mcspi_dma->dma_tx) {
1101 dma_release_channel(mcspi_dma->dma_tx);
1102 mcspi_dma->dma_tx = NULL;
1103 }
1104 }
1105
1106 if (gpio_is_valid(spi->cs_gpio))
1107 gpio_free(spi->cs_gpio);
1108}
1109
1110static irqreturn_t omap2_mcspi_irq_handler(int irq, void *data)
1111{
1112 struct omap2_mcspi *mcspi = data;
1113 u32 irqstat;
1114
1115 irqstat = mcspi_read_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS);
1116 if (!irqstat)
1117 return IRQ_NONE;
1118
1119 /* Disable IRQ and wakeup slave xfer task */
1120 mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQENABLE, 0);
1121 if (irqstat & OMAP2_MCSPI_IRQSTATUS_EOW)
1122 complete(&mcspi->txdone);
1123
1124 return IRQ_HANDLED;
1125}
1126
1127static int omap2_mcspi_slave_abort(struct spi_master *master)
1128{
1129 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1130 struct omap2_mcspi_dma *mcspi_dma = mcspi->dma_channels;
1131
1132 mcspi->slave_aborted = true;
1133 complete(&mcspi_dma->dma_rx_completion);
1134 complete(&mcspi_dma->dma_tx_completion);
1135 complete(&mcspi->txdone);
1136
1137 return 0;
1138}
1139
1140static int omap2_mcspi_transfer_one(struct spi_master *master,
1141 struct spi_device *spi,
1142 struct spi_transfer *t)
1143{
1144
1145 /* We only enable one channel at a time -- the one whose message is
1146 * -- although this controller would gladly
1147 * arbitrate among multiple channels. This corresponds to "single
1148 * channel" master mode. As a side effect, we need to manage the
1149 * chipselect with the FORCE bit ... CS != channel enable.
1150 */
1151
1152 struct omap2_mcspi *mcspi;
1153 struct omap2_mcspi_dma *mcspi_dma;
1154 struct omap2_mcspi_cs *cs;
1155 struct omap2_mcspi_device_config *cd;
1156 int par_override = 0;
1157 int status = 0;
1158 u32 chconf;
1159
1160 mcspi = spi_master_get_devdata(master);
1161 mcspi_dma = mcspi->dma_channels + spi->chip_select;
1162 cs = spi->controller_state;
1163 cd = spi->controller_data;
1164
1165 /*
1166 * The slave driver could have changed spi->mode in which case
1167 * it will be different from cs->mode (the current hardware setup).
1168 * If so, set par_override (even though its not a parity issue) so
1169 * omap2_mcspi_setup_transfer will be called to configure the hardware
1170 * with the correct mode on the first iteration of the loop below.
1171 */
1172 if (spi->mode != cs->mode)
1173 par_override = 1;
1174
1175 omap2_mcspi_set_enable(spi, 0);
1176
1177 if (gpio_is_valid(spi->cs_gpio))
1178 omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH);
1179
1180 if (par_override ||
1181 (t->speed_hz != spi->max_speed_hz) ||
1182 (t->bits_per_word != spi->bits_per_word)) {
1183 par_override = 1;
1184 status = omap2_mcspi_setup_transfer(spi, t);
1185 if (status < 0)
1186 goto out;
1187 if (t->speed_hz == spi->max_speed_hz &&
1188 t->bits_per_word == spi->bits_per_word)
1189 par_override = 0;
1190 }
1191 if (cd && cd->cs_per_word) {
1192 chconf = mcspi->ctx.modulctrl;
1193 chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1194 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1195 mcspi->ctx.modulctrl =
1196 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1197 }
1198
1199 chconf = mcspi_cached_chconf0(spi);
1200 chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1201 chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
1202
1203 if (t->tx_buf == NULL)
1204 chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1205 else if (t->rx_buf == NULL)
1206 chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1207
1208 if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1209 /* Turbo mode is for more than one word */
1210 if (t->len > ((cs->word_len + 7) >> 3))
1211 chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1212 }
1213
1214 mcspi_write_chconf0(spi, chconf);
1215
1216 if (t->len) {
1217 unsigned count;
1218
1219 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1220 master->cur_msg_mapped &&
1221 master->can_dma(master, spi, t))
1222 omap2_mcspi_set_fifo(spi, t, 1);
1223
1224 omap2_mcspi_set_enable(spi, 1);
1225
1226 /* RX_ONLY mode needs dummy data in TX reg */
1227 if (t->tx_buf == NULL)
1228 writel_relaxed(0, cs->base
1229 + OMAP2_MCSPI_TX0);
1230
1231 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1232 master->cur_msg_mapped &&
1233 master->can_dma(master, spi, t))
1234 count = omap2_mcspi_txrx_dma(spi, t);
1235 else
1236 count = omap2_mcspi_txrx_pio(spi, t);
1237
1238 if (count != t->len) {
1239 status = -EIO;
1240 goto out;
1241 }
1242 }
1243
1244 omap2_mcspi_set_enable(spi, 0);
1245
1246 if (mcspi->fifo_depth > 0)
1247 omap2_mcspi_set_fifo(spi, t, 0);
1248
1249out:
1250 /* Restore defaults if they were overriden */
1251 if (par_override) {
1252 par_override = 0;
1253 status = omap2_mcspi_setup_transfer(spi, NULL);
1254 }
1255
1256 if (cd && cd->cs_per_word) {
1257 chconf = mcspi->ctx.modulctrl;
1258 chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1259 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1260 mcspi->ctx.modulctrl =
1261 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1262 }
1263
1264 omap2_mcspi_set_enable(spi, 0);
1265
1266 if (gpio_is_valid(spi->cs_gpio))
1267 omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
1268
1269 if (mcspi->fifo_depth > 0 && t)
1270 omap2_mcspi_set_fifo(spi, t, 0);
1271
1272 return status;
1273}
1274
1275static int omap2_mcspi_prepare_message(struct spi_master *master,
1276 struct spi_message *msg)
1277{
1278 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1279 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1280 struct omap2_mcspi_cs *cs;
1281
1282 /* Only a single channel can have the FORCE bit enabled
1283 * in its chconf0 register.
1284 * Scan all channels and disable them except the current one.
1285 * A FORCE can remain from a last transfer having cs_change enabled
1286 */
1287 list_for_each_entry(cs, &ctx->cs, node) {
1288 if (msg->spi->controller_state == cs)
1289 continue;
1290
1291 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
1292 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1293 writel_relaxed(cs->chconf0,
1294 cs->base + OMAP2_MCSPI_CHCONF0);
1295 readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
1296 }
1297 }
1298
1299 return 0;
1300}
1301
1302static bool omap2_mcspi_can_dma(struct spi_master *master,
1303 struct spi_device *spi,
1304 struct spi_transfer *xfer)
1305{
1306 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1307 struct omap2_mcspi_dma *mcspi_dma =
1308 &mcspi->dma_channels[spi->chip_select];
1309
1310 if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx)
1311 return false;
1312
1313 if (spi_controller_is_slave(master))
1314 return true;
1315
1316 return (xfer->len >= DMA_MIN_BYTES);
1317}
1318
1319static int omap2_mcspi_controller_setup(struct omap2_mcspi *mcspi)
1320{
1321 struct spi_master *master = mcspi->master;
1322 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1323 int ret = 0;
1324
1325 ret = pm_runtime_get_sync(mcspi->dev);
1326 if (ret < 0) {
1327 pm_runtime_put_noidle(mcspi->dev);
1328
1329 return ret;
1330 }
1331
1332 mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1333 OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1334 ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1335
1336 omap2_mcspi_set_mode(master);
1337 pm_runtime_mark_last_busy(mcspi->dev);
1338 pm_runtime_put_autosuspend(mcspi->dev);
1339 return 0;
1340}
1341
1342/*
1343 * When SPI wake up from off-mode, CS is in activate state. If it was in
1344 * inactive state when driver was suspend, then force it to inactive state at
1345 * wake up.
1346 */
1347static int omap_mcspi_runtime_resume(struct device *dev)
1348{
1349 struct spi_master *master = dev_get_drvdata(dev);
1350 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1351 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1352 struct omap2_mcspi_cs *cs;
1353
1354 /* McSPI: context restore */
1355 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
1356 mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
1357
1358 list_for_each_entry(cs, &ctx->cs, node) {
1359 /*
1360 * We need to toggle CS state for OMAP take this
1361 * change in account.
1362 */
1363 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1364 cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1365 writel_relaxed(cs->chconf0,
1366 cs->base + OMAP2_MCSPI_CHCONF0);
1367 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1368 writel_relaxed(cs->chconf0,
1369 cs->base + OMAP2_MCSPI_CHCONF0);
1370 } else {
1371 writel_relaxed(cs->chconf0,
1372 cs->base + OMAP2_MCSPI_CHCONF0);
1373 }
1374 }
1375
1376 return 0;
1377}
1378
1379static struct omap2_mcspi_platform_config omap2_pdata = {
1380 .regs_offset = 0,
1381};
1382
1383static struct omap2_mcspi_platform_config omap4_pdata = {
1384 .regs_offset = OMAP4_MCSPI_REG_OFFSET,
1385};
1386
1387static const struct of_device_id omap_mcspi_of_match[] = {
1388 {
1389 .compatible = "ti,omap2-mcspi",
1390 .data = &omap2_pdata,
1391 },
1392 {
1393 .compatible = "ti,omap4-mcspi",
1394 .data = &omap4_pdata,
1395 },
1396 { },
1397};
1398MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1399
1400static int omap2_mcspi_probe(struct platform_device *pdev)
1401{
1402 struct spi_master *master;
1403 const struct omap2_mcspi_platform_config *pdata;
1404 struct omap2_mcspi *mcspi;
1405 struct resource *r;
1406 int status = 0, i;
1407 u32 regs_offset = 0;
1408 struct device_node *node = pdev->dev.of_node;
1409 const struct of_device_id *match;
1410
1411 if (of_property_read_bool(node, "spi-slave"))
1412 master = spi_alloc_slave(&pdev->dev, sizeof(*mcspi));
1413 else
1414 master = spi_alloc_master(&pdev->dev, sizeof(*mcspi));
1415 if (!master)
1416 return -ENOMEM;
1417
1418 /* the spi->mode bits understood by this driver: */
1419 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1420 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1421 master->setup = omap2_mcspi_setup;
1422 master->auto_runtime_pm = true;
1423 master->prepare_message = omap2_mcspi_prepare_message;
1424 master->can_dma = omap2_mcspi_can_dma;
1425 master->transfer_one = omap2_mcspi_transfer_one;
1426 master->set_cs = omap2_mcspi_set_cs;
1427 master->cleanup = omap2_mcspi_cleanup;
1428 master->slave_abort = omap2_mcspi_slave_abort;
1429 master->dev.of_node = node;
1430 master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1431 master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
1432
1433 platform_set_drvdata(pdev, master);
1434
1435 mcspi = spi_master_get_devdata(master);
1436 mcspi->master = master;
1437
1438 match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1439 if (match) {
1440 u32 num_cs = 1; /* default number of chipselect */
1441 pdata = match->data;
1442
1443 of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1444 master->num_chipselect = num_cs;
1445 if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1446 mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1447 } else {
1448 pdata = dev_get_platdata(&pdev->dev);
1449 master->num_chipselect = pdata->num_cs;
1450 mcspi->pin_dir = pdata->pin_dir;
1451 }
1452 regs_offset = pdata->regs_offset;
1453
1454 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1455 mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1456 if (IS_ERR(mcspi->base)) {
1457 status = PTR_ERR(mcspi->base);
1458 goto free_master;
1459 }
1460 mcspi->phys = r->start + regs_offset;
1461 mcspi->base += regs_offset;
1462
1463 mcspi->dev = &pdev->dev;
1464
1465 INIT_LIST_HEAD(&mcspi->ctx.cs);
1466
1467 mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1468 sizeof(struct omap2_mcspi_dma),
1469 GFP_KERNEL);
1470 if (mcspi->dma_channels == NULL) {
1471 status = -ENOMEM;
1472 goto free_master;
1473 }
1474
1475 for (i = 0; i < master->num_chipselect; i++) {
1476 sprintf(mcspi->dma_channels[i].dma_rx_ch_name, "rx%d", i);
1477 sprintf(mcspi->dma_channels[i].dma_tx_ch_name, "tx%d", i);
1478 }
1479
1480 status = platform_get_irq(pdev, 0);
1481 if (status == -EPROBE_DEFER)
1482 goto free_master;
1483 if (status < 0) {
1484 dev_err(&pdev->dev, "no irq resource found\n");
1485 goto free_master;
1486 }
1487 init_completion(&mcspi->txdone);
1488 status = devm_request_irq(&pdev->dev, status,
1489 omap2_mcspi_irq_handler, 0, pdev->name,
1490 mcspi);
1491 if (status) {
1492 dev_err(&pdev->dev, "Cannot request IRQ");
1493 goto free_master;
1494 }
1495
1496 pm_runtime_use_autosuspend(&pdev->dev);
1497 pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1498 pm_runtime_enable(&pdev->dev);
1499
1500 status = omap2_mcspi_controller_setup(mcspi);
1501 if (status < 0)
1502 goto disable_pm;
1503
1504 status = devm_spi_register_controller(&pdev->dev, master);
1505 if (status < 0)
1506 goto disable_pm;
1507
1508 return status;
1509
1510disable_pm:
1511 pm_runtime_dont_use_autosuspend(&pdev->dev);
1512 pm_runtime_put_sync(&pdev->dev);
1513 pm_runtime_disable(&pdev->dev);
1514free_master:
1515 spi_master_put(master);
1516 return status;
1517}
1518
1519static int omap2_mcspi_remove(struct platform_device *pdev)
1520{
1521 struct spi_master *master = platform_get_drvdata(pdev);
1522 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1523
1524 pm_runtime_dont_use_autosuspend(mcspi->dev);
1525 pm_runtime_put_sync(mcspi->dev);
1526 pm_runtime_disable(&pdev->dev);
1527
1528 return 0;
1529}
1530
1531/* work with hotplug and coldplug */
1532MODULE_ALIAS("platform:omap2_mcspi");
1533
1534static int __maybe_unused omap2_mcspi_suspend(struct device *dev)
1535{
1536 struct spi_master *master = dev_get_drvdata(dev);
1537 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1538 int error;
1539
1540 error = pinctrl_pm_select_sleep_state(dev);
1541 if (error)
1542 dev_warn(mcspi->dev, "%s: failed to set pins: %i\n",
1543 __func__, error);
1544
1545 error = spi_master_suspend(master);
1546 if (error)
1547 dev_warn(mcspi->dev, "%s: master suspend failed: %i\n",
1548 __func__, error);
1549
1550 return pm_runtime_force_suspend(dev);
1551}
1552
1553static int __maybe_unused omap2_mcspi_resume(struct device *dev)
1554{
1555 struct spi_master *master = dev_get_drvdata(dev);
1556 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1557 int error;
1558
1559 error = pinctrl_pm_select_default_state(dev);
1560 if (error)
1561 dev_warn(mcspi->dev, "%s: failed to set pins: %i\n",
1562 __func__, error);
1563
1564 error = spi_master_resume(master);
1565 if (error)
1566 dev_warn(mcspi->dev, "%s: master resume failed: %i\n",
1567 __func__, error);
1568
1569 return pm_runtime_force_resume(dev);
1570}
1571
1572static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1573 SET_SYSTEM_SLEEP_PM_OPS(omap2_mcspi_suspend,
1574 omap2_mcspi_resume)
1575 .runtime_resume = omap_mcspi_runtime_resume,
1576};
1577
1578static struct platform_driver omap2_mcspi_driver = {
1579 .driver = {
1580 .name = "omap2_mcspi",
1581 .pm = &omap2_mcspi_pm_ops,
1582 .of_match_table = omap_mcspi_of_match,
1583 },
1584 .probe = omap2_mcspi_probe,
1585 .remove = omap2_mcspi_remove,
1586};
1587
1588module_platform_driver(omap2_mcspi_driver);
1589MODULE_LICENSE("GPL");