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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 Yrjola <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
28#include <linux/spi/spi.h>
29
30#include "internals.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_controller *ctlr;
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 struct clk *ref_clk;
131 int fifo_depth;
132 bool target_aborted;
133 unsigned int pin_dir:1;
134 size_t max_xfer_len;
135 u32 ref_clk_hz;
136 bool use_multi_mode;
137};
138
139struct omap2_mcspi_cs {
140 void __iomem *base;
141 unsigned long phys;
142 int word_len;
143 u16 mode;
144 struct list_head node;
145 /* Context save and restore shadow register */
146 u32 chconf0, chctrl0;
147};
148
149static inline void mcspi_write_reg(struct spi_controller *ctlr,
150 int idx, u32 val)
151{
152 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
153
154 writel_relaxed(val, mcspi->base + idx);
155}
156
157static inline u32 mcspi_read_reg(struct spi_controller *ctlr, int idx)
158{
159 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
160
161 return readl_relaxed(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 writel_relaxed(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 readl_relaxed(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 inline int mcspi_bytes_per_word(int word_len)
196{
197 if (word_len <= 8)
198 return 1;
199 else if (word_len <= 16)
200 return 2;
201 else /* word_len <= 32 */
202 return 4;
203}
204
205static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
206 int is_read, int enable)
207{
208 u32 l, rw;
209
210 l = mcspi_cached_chconf0(spi);
211
212 if (is_read) /* 1 is read, 0 write */
213 rw = OMAP2_MCSPI_CHCONF_DMAR;
214 else
215 rw = OMAP2_MCSPI_CHCONF_DMAW;
216
217 if (enable)
218 l |= rw;
219 else
220 l &= ~rw;
221
222 mcspi_write_chconf0(spi, l);
223}
224
225static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
226{
227 struct omap2_mcspi_cs *cs = spi->controller_state;
228 u32 l;
229
230 l = cs->chctrl0;
231 if (enable)
232 l |= OMAP2_MCSPI_CHCTRL_EN;
233 else
234 l &= ~OMAP2_MCSPI_CHCTRL_EN;
235 cs->chctrl0 = l;
236 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
237 /* Flash post-writes */
238 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
239}
240
241static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable)
242{
243 struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller);
244 u32 l;
245
246 /* The controller handles the inverted chip selects
247 * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert
248 * the inversion from the core spi_set_cs function.
249 */
250 if (spi->mode & SPI_CS_HIGH)
251 enable = !enable;
252
253 if (spi->controller_state) {
254 int err = pm_runtime_resume_and_get(mcspi->dev);
255 if (err < 0) {
256 dev_err(mcspi->dev, "failed to get sync: %d\n", err);
257 return;
258 }
259
260 l = mcspi_cached_chconf0(spi);
261
262 /* Only enable chip select manually if single mode is used */
263 if (mcspi->use_multi_mode) {
264 l &= ~OMAP2_MCSPI_CHCONF_FORCE;
265 } else {
266 if (enable)
267 l &= ~OMAP2_MCSPI_CHCONF_FORCE;
268 else
269 l |= OMAP2_MCSPI_CHCONF_FORCE;
270 }
271
272 mcspi_write_chconf0(spi, l);
273
274 pm_runtime_mark_last_busy(mcspi->dev);
275 pm_runtime_put_autosuspend(mcspi->dev);
276 }
277}
278
279static void omap2_mcspi_set_mode(struct spi_controller *ctlr)
280{
281 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
282 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
283 u32 l;
284
285 /*
286 * Choose host or target mode
287 */
288 l = mcspi_read_reg(ctlr, OMAP2_MCSPI_MODULCTRL);
289 l &= ~(OMAP2_MCSPI_MODULCTRL_STEST);
290 if (spi_controller_is_target(ctlr)) {
291 l |= (OMAP2_MCSPI_MODULCTRL_MS);
292 } else {
293 l &= ~(OMAP2_MCSPI_MODULCTRL_MS);
294
295 /* Enable single mode if needed */
296 if (mcspi->use_multi_mode)
297 l &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
298 else
299 l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
300 }
301 mcspi_write_reg(ctlr, OMAP2_MCSPI_MODULCTRL, l);
302
303 ctx->modulctrl = l;
304}
305
306static void omap2_mcspi_set_fifo(const struct spi_device *spi,
307 struct spi_transfer *t, int enable)
308{
309 struct spi_controller *ctlr = spi->controller;
310 struct omap2_mcspi_cs *cs = spi->controller_state;
311 struct omap2_mcspi *mcspi;
312 unsigned int wcnt;
313 int max_fifo_depth, bytes_per_word;
314 u32 chconf, xferlevel;
315
316 mcspi = spi_controller_get_devdata(ctlr);
317
318 chconf = mcspi_cached_chconf0(spi);
319 if (enable) {
320 bytes_per_word = mcspi_bytes_per_word(cs->word_len);
321 if (t->len % bytes_per_word != 0)
322 goto disable_fifo;
323
324 if (t->rx_buf != NULL && t->tx_buf != NULL)
325 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
326 else
327 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
328
329 wcnt = t->len / bytes_per_word;
330 if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
331 goto disable_fifo;
332
333 xferlevel = wcnt << 16;
334 if (t->rx_buf != NULL) {
335 chconf |= OMAP2_MCSPI_CHCONF_FFER;
336 xferlevel |= (bytes_per_word - 1) << 8;
337 }
338
339 if (t->tx_buf != NULL) {
340 chconf |= OMAP2_MCSPI_CHCONF_FFET;
341 xferlevel |= bytes_per_word - 1;
342 }
343
344 mcspi_write_reg(ctlr, OMAP2_MCSPI_XFERLEVEL, xferlevel);
345 mcspi_write_chconf0(spi, chconf);
346 mcspi->fifo_depth = max_fifo_depth;
347
348 return;
349 }
350
351disable_fifo:
352 if (t->rx_buf != NULL)
353 chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
354
355 if (t->tx_buf != NULL)
356 chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
357
358 mcspi_write_chconf0(spi, chconf);
359 mcspi->fifo_depth = 0;
360}
361
362static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
363{
364 unsigned long timeout;
365
366 timeout = jiffies + msecs_to_jiffies(1000);
367 while (!(readl_relaxed(reg) & bit)) {
368 if (time_after(jiffies, timeout)) {
369 if (!(readl_relaxed(reg) & bit))
370 return -ETIMEDOUT;
371 else
372 return 0;
373 }
374 cpu_relax();
375 }
376 return 0;
377}
378
379static int mcspi_wait_for_completion(struct omap2_mcspi *mcspi,
380 struct completion *x)
381{
382 if (spi_controller_is_target(mcspi->ctlr)) {
383 if (wait_for_completion_interruptible(x) ||
384 mcspi->target_aborted)
385 return -EINTR;
386 } else {
387 wait_for_completion(x);
388 }
389
390 return 0;
391}
392
393static void omap2_mcspi_rx_callback(void *data)
394{
395 struct spi_device *spi = data;
396 struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller);
397 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)];
398
399 /* We must disable the DMA RX request */
400 omap2_mcspi_set_dma_req(spi, 1, 0);
401
402 complete(&mcspi_dma->dma_rx_completion);
403}
404
405static void omap2_mcspi_tx_callback(void *data)
406{
407 struct spi_device *spi = data;
408 struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller);
409 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)];
410
411 /* We must disable the DMA TX request */
412 omap2_mcspi_set_dma_req(spi, 0, 0);
413
414 complete(&mcspi_dma->dma_tx_completion);
415}
416
417static void omap2_mcspi_tx_dma(struct spi_device *spi,
418 struct spi_transfer *xfer,
419 struct dma_slave_config cfg)
420{
421 struct omap2_mcspi *mcspi;
422 struct omap2_mcspi_dma *mcspi_dma;
423 struct dma_async_tx_descriptor *tx;
424
425 mcspi = spi_controller_get_devdata(spi->controller);
426 mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)];
427
428 dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
429
430 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, xfer->tx_sg.sgl,
431 xfer->tx_sg.nents,
432 DMA_MEM_TO_DEV,
433 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
434 if (tx) {
435 tx->callback = omap2_mcspi_tx_callback;
436 tx->callback_param = spi;
437 dmaengine_submit(tx);
438 } else {
439 /* FIXME: fall back to PIO? */
440 }
441 dma_async_issue_pending(mcspi_dma->dma_tx);
442 omap2_mcspi_set_dma_req(spi, 0, 1);
443}
444
445static unsigned
446omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
447 struct dma_slave_config cfg,
448 unsigned es)
449{
450 struct omap2_mcspi *mcspi;
451 struct omap2_mcspi_dma *mcspi_dma;
452 unsigned int count, transfer_reduction = 0;
453 struct scatterlist *sg_out[2];
454 int nb_sizes = 0, out_mapped_nents[2], ret, x;
455 size_t sizes[2];
456 u32 l;
457 int elements = 0;
458 int word_len, element_count;
459 struct omap2_mcspi_cs *cs = spi->controller_state;
460 void __iomem *chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
461 struct dma_async_tx_descriptor *tx;
462
463 mcspi = spi_controller_get_devdata(spi->controller);
464 mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)];
465 count = xfer->len;
466
467 /*
468 * In the "End-of-Transfer Procedure" section for DMA RX in OMAP35x TRM
469 * it mentions reducing DMA transfer length by one element in host
470 * normal mode.
471 */
472 if (mcspi->fifo_depth == 0)
473 transfer_reduction = es;
474
475 word_len = cs->word_len;
476 l = mcspi_cached_chconf0(spi);
477
478 if (word_len <= 8)
479 element_count = count;
480 else if (word_len <= 16)
481 element_count = count >> 1;
482 else /* word_len <= 32 */
483 element_count = count >> 2;
484
485
486 dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
487
488 /*
489 * Reduce DMA transfer length by one more if McSPI is
490 * configured in turbo mode.
491 */
492 if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
493 transfer_reduction += es;
494
495 if (transfer_reduction) {
496 /* Split sgl into two. The second sgl won't be used. */
497 sizes[0] = count - transfer_reduction;
498 sizes[1] = transfer_reduction;
499 nb_sizes = 2;
500 } else {
501 /*
502 * Don't bother splitting the sgl. This essentially
503 * clones the original sgl.
504 */
505 sizes[0] = count;
506 nb_sizes = 1;
507 }
508
509 ret = sg_split(xfer->rx_sg.sgl, xfer->rx_sg.nents, 0, nb_sizes,
510 sizes, sg_out, out_mapped_nents, GFP_KERNEL);
511
512 if (ret < 0) {
513 dev_err(&spi->dev, "sg_split failed\n");
514 return 0;
515 }
516
517 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, sg_out[0],
518 out_mapped_nents[0], DMA_DEV_TO_MEM,
519 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
520 if (tx) {
521 tx->callback = omap2_mcspi_rx_callback;
522 tx->callback_param = spi;
523 dmaengine_submit(tx);
524 } else {
525 /* FIXME: fall back to PIO? */
526 }
527
528 dma_async_issue_pending(mcspi_dma->dma_rx);
529 omap2_mcspi_set_dma_req(spi, 1, 1);
530
531 ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_rx_completion);
532 if (ret || mcspi->target_aborted) {
533 dmaengine_terminate_sync(mcspi_dma->dma_rx);
534 omap2_mcspi_set_dma_req(spi, 1, 0);
535 return 0;
536 }
537
538 for (x = 0; x < nb_sizes; x++)
539 kfree(sg_out[x]);
540
541 if (mcspi->fifo_depth > 0)
542 return count;
543
544 /*
545 * Due to the DMA transfer length reduction the missing bytes must
546 * be read manually to receive all of the expected data.
547 */
548 omap2_mcspi_set_enable(spi, 0);
549
550 elements = element_count - 1;
551
552 if (l & OMAP2_MCSPI_CHCONF_TURBO) {
553 elements--;
554
555 if (!mcspi_wait_for_reg_bit(chstat_reg,
556 OMAP2_MCSPI_CHSTAT_RXS)) {
557 u32 w;
558
559 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
560 if (word_len <= 8)
561 ((u8 *)xfer->rx_buf)[elements++] = w;
562 else if (word_len <= 16)
563 ((u16 *)xfer->rx_buf)[elements++] = w;
564 else /* word_len <= 32 */
565 ((u32 *)xfer->rx_buf)[elements++] = w;
566 } else {
567 int bytes_per_word = mcspi_bytes_per_word(word_len);
568 dev_err(&spi->dev, "DMA RX penultimate word empty\n");
569 count -= (bytes_per_word << 1);
570 omap2_mcspi_set_enable(spi, 1);
571 return count;
572 }
573 }
574 if (!mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS)) {
575 u32 w;
576
577 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
578 if (word_len <= 8)
579 ((u8 *)xfer->rx_buf)[elements] = w;
580 else if (word_len <= 16)
581 ((u16 *)xfer->rx_buf)[elements] = w;
582 else /* word_len <= 32 */
583 ((u32 *)xfer->rx_buf)[elements] = w;
584 } else {
585 dev_err(&spi->dev, "DMA RX last word empty\n");
586 count -= mcspi_bytes_per_word(word_len);
587 }
588 omap2_mcspi_set_enable(spi, 1);
589 return count;
590}
591
592static unsigned
593omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
594{
595 struct omap2_mcspi *mcspi;
596 struct omap2_mcspi_cs *cs = spi->controller_state;
597 struct omap2_mcspi_dma *mcspi_dma;
598 unsigned int count;
599 u8 *rx;
600 const u8 *tx;
601 struct dma_slave_config cfg;
602 enum dma_slave_buswidth width;
603 unsigned es;
604 void __iomem *chstat_reg;
605 void __iomem *irqstat_reg;
606 int wait_res;
607
608 mcspi = spi_controller_get_devdata(spi->controller);
609 mcspi_dma = &mcspi->dma_channels[spi_get_chipselect(spi, 0)];
610
611 if (cs->word_len <= 8) {
612 width = DMA_SLAVE_BUSWIDTH_1_BYTE;
613 es = 1;
614 } else if (cs->word_len <= 16) {
615 width = DMA_SLAVE_BUSWIDTH_2_BYTES;
616 es = 2;
617 } else {
618 width = DMA_SLAVE_BUSWIDTH_4_BYTES;
619 es = 4;
620 }
621
622 count = xfer->len;
623
624 memset(&cfg, 0, sizeof(cfg));
625 cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
626 cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
627 cfg.src_addr_width = width;
628 cfg.dst_addr_width = width;
629 cfg.src_maxburst = 1;
630 cfg.dst_maxburst = 1;
631
632 rx = xfer->rx_buf;
633 tx = xfer->tx_buf;
634
635 mcspi->target_aborted = false;
636 reinit_completion(&mcspi_dma->dma_tx_completion);
637 reinit_completion(&mcspi_dma->dma_rx_completion);
638 reinit_completion(&mcspi->txdone);
639 if (tx) {
640 /* Enable EOW IRQ to know end of tx in target mode */
641 if (spi_controller_is_target(spi->controller))
642 mcspi_write_reg(spi->controller,
643 OMAP2_MCSPI_IRQENABLE,
644 OMAP2_MCSPI_IRQSTATUS_EOW);
645 omap2_mcspi_tx_dma(spi, xfer, cfg);
646 }
647
648 if (rx != NULL)
649 count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
650
651 if (tx != NULL) {
652 int ret;
653
654 ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_tx_completion);
655 if (ret || mcspi->target_aborted) {
656 dmaengine_terminate_sync(mcspi_dma->dma_tx);
657 omap2_mcspi_set_dma_req(spi, 0, 0);
658 return 0;
659 }
660
661 if (spi_controller_is_target(mcspi->ctlr)) {
662 ret = mcspi_wait_for_completion(mcspi, &mcspi->txdone);
663 if (ret || mcspi->target_aborted)
664 return 0;
665 }
666
667 if (mcspi->fifo_depth > 0) {
668 irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
669
670 if (mcspi_wait_for_reg_bit(irqstat_reg,
671 OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
672 dev_err(&spi->dev, "EOW timed out\n");
673
674 mcspi_write_reg(mcspi->ctlr, OMAP2_MCSPI_IRQSTATUS,
675 OMAP2_MCSPI_IRQSTATUS_EOW);
676 }
677
678 /* for TX_ONLY mode, be sure all words have shifted out */
679 if (rx == NULL) {
680 chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
681 if (mcspi->fifo_depth > 0) {
682 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
683 OMAP2_MCSPI_CHSTAT_TXFFE);
684 if (wait_res < 0)
685 dev_err(&spi->dev, "TXFFE timed out\n");
686 } else {
687 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
688 OMAP2_MCSPI_CHSTAT_TXS);
689 if (wait_res < 0)
690 dev_err(&spi->dev, "TXS timed out\n");
691 }
692 if (wait_res >= 0 &&
693 (mcspi_wait_for_reg_bit(chstat_reg,
694 OMAP2_MCSPI_CHSTAT_EOT) < 0))
695 dev_err(&spi->dev, "EOT timed out\n");
696 }
697 }
698 return count;
699}
700
701static unsigned
702omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
703{
704 struct omap2_mcspi_cs *cs = spi->controller_state;
705 unsigned int count, c;
706 u32 l;
707 void __iomem *base = cs->base;
708 void __iomem *tx_reg;
709 void __iomem *rx_reg;
710 void __iomem *chstat_reg;
711 int word_len;
712
713 count = xfer->len;
714 c = count;
715 word_len = cs->word_len;
716
717 l = mcspi_cached_chconf0(spi);
718
719 /* We store the pre-calculated register addresses on stack to speed
720 * up the transfer loop. */
721 tx_reg = base + OMAP2_MCSPI_TX0;
722 rx_reg = base + OMAP2_MCSPI_RX0;
723 chstat_reg = base + OMAP2_MCSPI_CHSTAT0;
724
725 if (c < (word_len>>3))
726 return 0;
727
728 if (word_len <= 8) {
729 u8 *rx;
730 const u8 *tx;
731
732 rx = xfer->rx_buf;
733 tx = xfer->tx_buf;
734
735 do {
736 c -= 1;
737 if (tx != NULL) {
738 if (mcspi_wait_for_reg_bit(chstat_reg,
739 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
740 dev_err(&spi->dev, "TXS timed out\n");
741 goto out;
742 }
743 dev_vdbg(&spi->dev, "write-%d %02x\n",
744 word_len, *tx);
745 writel_relaxed(*tx++, tx_reg);
746 }
747 if (rx != NULL) {
748 if (mcspi_wait_for_reg_bit(chstat_reg,
749 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
750 dev_err(&spi->dev, "RXS timed out\n");
751 goto out;
752 }
753
754 if (c == 1 && tx == NULL &&
755 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
756 omap2_mcspi_set_enable(spi, 0);
757 *rx++ = readl_relaxed(rx_reg);
758 dev_vdbg(&spi->dev, "read-%d %02x\n",
759 word_len, *(rx - 1));
760 if (mcspi_wait_for_reg_bit(chstat_reg,
761 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
762 dev_err(&spi->dev,
763 "RXS timed out\n");
764 goto out;
765 }
766 c = 0;
767 } else if (c == 0 && tx == NULL) {
768 omap2_mcspi_set_enable(spi, 0);
769 }
770
771 *rx++ = readl_relaxed(rx_reg);
772 dev_vdbg(&spi->dev, "read-%d %02x\n",
773 word_len, *(rx - 1));
774 }
775 /* Add word delay between each word */
776 spi_delay_exec(&xfer->word_delay, xfer);
777 } while (c);
778 } else if (word_len <= 16) {
779 u16 *rx;
780 const u16 *tx;
781
782 rx = xfer->rx_buf;
783 tx = xfer->tx_buf;
784 do {
785 c -= 2;
786 if (tx != NULL) {
787 if (mcspi_wait_for_reg_bit(chstat_reg,
788 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
789 dev_err(&spi->dev, "TXS timed out\n");
790 goto out;
791 }
792 dev_vdbg(&spi->dev, "write-%d %04x\n",
793 word_len, *tx);
794 writel_relaxed(*tx++, tx_reg);
795 }
796 if (rx != NULL) {
797 if (mcspi_wait_for_reg_bit(chstat_reg,
798 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
799 dev_err(&spi->dev, "RXS timed out\n");
800 goto out;
801 }
802
803 if (c == 2 && tx == NULL &&
804 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
805 omap2_mcspi_set_enable(spi, 0);
806 *rx++ = readl_relaxed(rx_reg);
807 dev_vdbg(&spi->dev, "read-%d %04x\n",
808 word_len, *(rx - 1));
809 if (mcspi_wait_for_reg_bit(chstat_reg,
810 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
811 dev_err(&spi->dev,
812 "RXS timed out\n");
813 goto out;
814 }
815 c = 0;
816 } else if (c == 0 && tx == NULL) {
817 omap2_mcspi_set_enable(spi, 0);
818 }
819
820 *rx++ = readl_relaxed(rx_reg);
821 dev_vdbg(&spi->dev, "read-%d %04x\n",
822 word_len, *(rx - 1));
823 }
824 /* Add word delay between each word */
825 spi_delay_exec(&xfer->word_delay, xfer);
826 } while (c >= 2);
827 } else if (word_len <= 32) {
828 u32 *rx;
829 const u32 *tx;
830
831 rx = xfer->rx_buf;
832 tx = xfer->tx_buf;
833 do {
834 c -= 4;
835 if (tx != NULL) {
836 if (mcspi_wait_for_reg_bit(chstat_reg,
837 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
838 dev_err(&spi->dev, "TXS timed out\n");
839 goto out;
840 }
841 dev_vdbg(&spi->dev, "write-%d %08x\n",
842 word_len, *tx);
843 writel_relaxed(*tx++, tx_reg);
844 }
845 if (rx != NULL) {
846 if (mcspi_wait_for_reg_bit(chstat_reg,
847 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
848 dev_err(&spi->dev, "RXS timed out\n");
849 goto out;
850 }
851
852 if (c == 4 && tx == NULL &&
853 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
854 omap2_mcspi_set_enable(spi, 0);
855 *rx++ = readl_relaxed(rx_reg);
856 dev_vdbg(&spi->dev, "read-%d %08x\n",
857 word_len, *(rx - 1));
858 if (mcspi_wait_for_reg_bit(chstat_reg,
859 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
860 dev_err(&spi->dev,
861 "RXS timed out\n");
862 goto out;
863 }
864 c = 0;
865 } else if (c == 0 && tx == NULL) {
866 omap2_mcspi_set_enable(spi, 0);
867 }
868
869 *rx++ = readl_relaxed(rx_reg);
870 dev_vdbg(&spi->dev, "read-%d %08x\n",
871 word_len, *(rx - 1));
872 }
873 /* Add word delay between each word */
874 spi_delay_exec(&xfer->word_delay, xfer);
875 } while (c >= 4);
876 }
877
878 /* for TX_ONLY mode, be sure all words have shifted out */
879 if (xfer->rx_buf == NULL) {
880 if (mcspi_wait_for_reg_bit(chstat_reg,
881 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
882 dev_err(&spi->dev, "TXS timed out\n");
883 } else if (mcspi_wait_for_reg_bit(chstat_reg,
884 OMAP2_MCSPI_CHSTAT_EOT) < 0)
885 dev_err(&spi->dev, "EOT timed out\n");
886
887 /* disable chan to purge rx datas received in TX_ONLY transfer,
888 * otherwise these rx datas will affect the direct following
889 * RX_ONLY transfer.
890 */
891 omap2_mcspi_set_enable(spi, 0);
892 }
893out:
894 omap2_mcspi_set_enable(spi, 1);
895 return count - c;
896}
897
898static u32 omap2_mcspi_calc_divisor(u32 speed_hz, u32 ref_clk_hz)
899{
900 u32 div;
901
902 for (div = 0; div < 15; div++)
903 if (speed_hz >= (ref_clk_hz >> div))
904 return div;
905
906 return 15;
907}
908
909/* called only when no transfer is active to this device */
910static int omap2_mcspi_setup_transfer(struct spi_device *spi,
911 struct spi_transfer *t)
912{
913 struct omap2_mcspi_cs *cs = spi->controller_state;
914 struct omap2_mcspi *mcspi;
915 u32 ref_clk_hz, l = 0, clkd = 0, div, extclk = 0, clkg = 0;
916 u8 word_len = spi->bits_per_word;
917 u32 speed_hz = spi->max_speed_hz;
918
919 mcspi = spi_controller_get_devdata(spi->controller);
920
921 if (t != NULL && t->bits_per_word)
922 word_len = t->bits_per_word;
923
924 cs->word_len = word_len;
925
926 if (t && t->speed_hz)
927 speed_hz = t->speed_hz;
928
929 ref_clk_hz = mcspi->ref_clk_hz;
930 speed_hz = min_t(u32, speed_hz, ref_clk_hz);
931 if (speed_hz < (ref_clk_hz / OMAP2_MCSPI_MAX_DIVIDER)) {
932 clkd = omap2_mcspi_calc_divisor(speed_hz, ref_clk_hz);
933 speed_hz = ref_clk_hz >> clkd;
934 clkg = 0;
935 } else {
936 div = (ref_clk_hz + speed_hz - 1) / speed_hz;
937 speed_hz = ref_clk_hz / div;
938 clkd = (div - 1) & 0xf;
939 extclk = (div - 1) >> 4;
940 clkg = OMAP2_MCSPI_CHCONF_CLKG;
941 }
942
943 l = mcspi_cached_chconf0(spi);
944
945 /* standard 4-wire host mode: SCK, MOSI/out, MISO/in, nCS
946 * REVISIT: this controller could support SPI_3WIRE mode.
947 */
948 if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
949 l &= ~OMAP2_MCSPI_CHCONF_IS;
950 l &= ~OMAP2_MCSPI_CHCONF_DPE1;
951 l |= OMAP2_MCSPI_CHCONF_DPE0;
952 } else {
953 l |= OMAP2_MCSPI_CHCONF_IS;
954 l |= OMAP2_MCSPI_CHCONF_DPE1;
955 l &= ~OMAP2_MCSPI_CHCONF_DPE0;
956 }
957
958 /* wordlength */
959 l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
960 l |= (word_len - 1) << 7;
961
962 /* set chipselect polarity; manage with FORCE */
963 if (!(spi->mode & SPI_CS_HIGH))
964 l |= OMAP2_MCSPI_CHCONF_EPOL; /* active-low; normal */
965 else
966 l &= ~OMAP2_MCSPI_CHCONF_EPOL;
967
968 /* set clock divisor */
969 l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
970 l |= clkd << 2;
971
972 /* set clock granularity */
973 l &= ~OMAP2_MCSPI_CHCONF_CLKG;
974 l |= clkg;
975 if (clkg) {
976 cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
977 cs->chctrl0 |= extclk << 8;
978 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
979 }
980
981 /* set SPI mode 0..3 */
982 if (spi->mode & SPI_CPOL)
983 l |= OMAP2_MCSPI_CHCONF_POL;
984 else
985 l &= ~OMAP2_MCSPI_CHCONF_POL;
986 if (spi->mode & SPI_CPHA)
987 l |= OMAP2_MCSPI_CHCONF_PHA;
988 else
989 l &= ~OMAP2_MCSPI_CHCONF_PHA;
990
991 mcspi_write_chconf0(spi, l);
992
993 cs->mode = spi->mode;
994
995 dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
996 speed_hz,
997 (spi->mode & SPI_CPHA) ? "trailing" : "leading",
998 (spi->mode & SPI_CPOL) ? "inverted" : "normal");
999
1000 return 0;
1001}
1002
1003/*
1004 * Note that we currently allow DMA only if we get a channel
1005 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
1006 */
1007static int omap2_mcspi_request_dma(struct omap2_mcspi *mcspi,
1008 struct omap2_mcspi_dma *mcspi_dma)
1009{
1010 int ret = 0;
1011
1012 mcspi_dma->dma_rx = dma_request_chan(mcspi->dev,
1013 mcspi_dma->dma_rx_ch_name);
1014 if (IS_ERR(mcspi_dma->dma_rx)) {
1015 ret = PTR_ERR(mcspi_dma->dma_rx);
1016 mcspi_dma->dma_rx = NULL;
1017 goto no_dma;
1018 }
1019
1020 mcspi_dma->dma_tx = dma_request_chan(mcspi->dev,
1021 mcspi_dma->dma_tx_ch_name);
1022 if (IS_ERR(mcspi_dma->dma_tx)) {
1023 ret = PTR_ERR(mcspi_dma->dma_tx);
1024 mcspi_dma->dma_tx = NULL;
1025 dma_release_channel(mcspi_dma->dma_rx);
1026 mcspi_dma->dma_rx = NULL;
1027 }
1028
1029 init_completion(&mcspi_dma->dma_rx_completion);
1030 init_completion(&mcspi_dma->dma_tx_completion);
1031
1032no_dma:
1033 return ret;
1034}
1035
1036static void omap2_mcspi_release_dma(struct spi_controller *ctlr)
1037{
1038 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
1039 struct omap2_mcspi_dma *mcspi_dma;
1040 int i;
1041
1042 for (i = 0; i < ctlr->num_chipselect; i++) {
1043 mcspi_dma = &mcspi->dma_channels[i];
1044
1045 if (mcspi_dma->dma_rx) {
1046 dma_release_channel(mcspi_dma->dma_rx);
1047 mcspi_dma->dma_rx = NULL;
1048 }
1049 if (mcspi_dma->dma_tx) {
1050 dma_release_channel(mcspi_dma->dma_tx);
1051 mcspi_dma->dma_tx = NULL;
1052 }
1053 }
1054}
1055
1056static void omap2_mcspi_cleanup(struct spi_device *spi)
1057{
1058 struct omap2_mcspi_cs *cs;
1059
1060 if (spi->controller_state) {
1061 /* Unlink controller state from context save list */
1062 cs = spi->controller_state;
1063 list_del(&cs->node);
1064
1065 kfree(cs);
1066 }
1067}
1068
1069static int omap2_mcspi_setup(struct spi_device *spi)
1070{
1071 bool initial_setup = false;
1072 int ret;
1073 struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller);
1074 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1075 struct omap2_mcspi_cs *cs = spi->controller_state;
1076
1077 if (!cs) {
1078 cs = kzalloc(sizeof(*cs), GFP_KERNEL);
1079 if (!cs)
1080 return -ENOMEM;
1081 cs->base = mcspi->base + spi_get_chipselect(spi, 0) * 0x14;
1082 cs->phys = mcspi->phys + spi_get_chipselect(spi, 0) * 0x14;
1083 cs->mode = 0;
1084 cs->chconf0 = 0;
1085 cs->chctrl0 = 0;
1086 spi->controller_state = cs;
1087 /* Link this to context save list */
1088 list_add_tail(&cs->node, &ctx->cs);
1089 initial_setup = true;
1090 }
1091
1092 ret = pm_runtime_resume_and_get(mcspi->dev);
1093 if (ret < 0) {
1094 if (initial_setup)
1095 omap2_mcspi_cleanup(spi);
1096
1097 return ret;
1098 }
1099
1100 ret = omap2_mcspi_setup_transfer(spi, NULL);
1101 if (ret && initial_setup)
1102 omap2_mcspi_cleanup(spi);
1103
1104 pm_runtime_mark_last_busy(mcspi->dev);
1105 pm_runtime_put_autosuspend(mcspi->dev);
1106
1107 return ret;
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->ctlr, OMAP2_MCSPI_IRQSTATUS);
1116 if (!irqstat)
1117 return IRQ_NONE;
1118
1119 /* Disable IRQ and wakeup target xfer task */
1120 mcspi_write_reg(mcspi->ctlr, 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_target_abort(struct spi_controller *ctlr)
1128{
1129 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
1130 struct omap2_mcspi_dma *mcspi_dma = mcspi->dma_channels;
1131
1132 mcspi->target_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_controller *ctlr,
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" host 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_controller_get_devdata(ctlr);
1161 mcspi_dma = mcspi->dma_channels + spi_get_chipselect(spi, 0);
1162 cs = spi->controller_state;
1163 cd = spi->controller_data;
1164
1165 /*
1166 * The target 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 (spi_get_csgpiod(spi, 0))
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
1192 chconf = mcspi_cached_chconf0(spi);
1193 chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1194 chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
1195
1196 if (t->tx_buf == NULL)
1197 chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1198 else if (t->rx_buf == NULL)
1199 chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1200
1201 if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1202 /* Turbo mode is for more than one word */
1203 if (t->len > ((cs->word_len + 7) >> 3))
1204 chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1205 }
1206
1207 mcspi_write_chconf0(spi, chconf);
1208
1209 if (t->len) {
1210 unsigned count;
1211
1212 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1213 spi_xfer_is_dma_mapped(ctlr, spi, t))
1214 omap2_mcspi_set_fifo(spi, t, 1);
1215
1216 omap2_mcspi_set_enable(spi, 1);
1217
1218 /* RX_ONLY mode needs dummy data in TX reg */
1219 if (t->tx_buf == NULL)
1220 writel_relaxed(0, cs->base
1221 + OMAP2_MCSPI_TX0);
1222
1223 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1224 spi_xfer_is_dma_mapped(ctlr, spi, t))
1225 count = omap2_mcspi_txrx_dma(spi, t);
1226 else
1227 count = omap2_mcspi_txrx_pio(spi, t);
1228
1229 if (count != t->len) {
1230 status = -EIO;
1231 goto out;
1232 }
1233 }
1234
1235 omap2_mcspi_set_enable(spi, 0);
1236
1237 if (mcspi->fifo_depth > 0)
1238 omap2_mcspi_set_fifo(spi, t, 0);
1239
1240out:
1241 /* Restore defaults if they were overriden */
1242 if (par_override) {
1243 par_override = 0;
1244 status = omap2_mcspi_setup_transfer(spi, NULL);
1245 }
1246
1247 omap2_mcspi_set_enable(spi, 0);
1248
1249 if (spi_get_csgpiod(spi, 0))
1250 omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
1251
1252 if (mcspi->fifo_depth > 0 && t)
1253 omap2_mcspi_set_fifo(spi, t, 0);
1254
1255 return status;
1256}
1257
1258static int omap2_mcspi_prepare_message(struct spi_controller *ctlr,
1259 struct spi_message *msg)
1260{
1261 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
1262 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1263 struct omap2_mcspi_cs *cs;
1264 struct spi_transfer *tr;
1265 u8 bits_per_word;
1266
1267 /*
1268 * The conditions are strict, it is mandatory to check each transfer of the list to see if
1269 * multi-mode is applicable.
1270 */
1271 mcspi->use_multi_mode = true;
1272 list_for_each_entry(tr, &msg->transfers, transfer_list) {
1273 if (!tr->bits_per_word)
1274 bits_per_word = msg->spi->bits_per_word;
1275 else
1276 bits_per_word = tr->bits_per_word;
1277
1278 /*
1279 * Check if this transfer contains only one word;
1280 */
1281 if (bits_per_word < 8 && tr->len == 1) {
1282 /* multi-mode is applicable, only one word (1..7 bits) */
1283 } else if (bits_per_word >= 8 && tr->len == bits_per_word / 8) {
1284 /* multi-mode is applicable, only one word (8..32 bits) */
1285 } else {
1286 /* multi-mode is not applicable: more than one word in the transfer */
1287 mcspi->use_multi_mode = false;
1288 }
1289
1290 /* Check if transfer asks to change the CS status after the transfer */
1291 if (!tr->cs_change)
1292 mcspi->use_multi_mode = false;
1293
1294 /*
1295 * If at least one message is not compatible, switch back to single mode
1296 *
1297 * The bits_per_word of certain transfer can be different, but it will have no
1298 * impact on the signal itself.
1299 */
1300 if (!mcspi->use_multi_mode)
1301 break;
1302 }
1303
1304 omap2_mcspi_set_mode(ctlr);
1305
1306 /* In single mode only a single channel can have the FORCE bit enabled
1307 * in its chconf0 register.
1308 * Scan all channels and disable them except the current one.
1309 * A FORCE can remain from a last transfer having cs_change enabled
1310 *
1311 * In multi mode all FORCE bits must be disabled.
1312 */
1313 list_for_each_entry(cs, &ctx->cs, node) {
1314 if (msg->spi->controller_state == cs && !mcspi->use_multi_mode) {
1315 continue;
1316 }
1317
1318 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
1319 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1320 writel_relaxed(cs->chconf0,
1321 cs->base + OMAP2_MCSPI_CHCONF0);
1322 readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
1323 }
1324 }
1325
1326 return 0;
1327}
1328
1329static bool omap2_mcspi_can_dma(struct spi_controller *ctlr,
1330 struct spi_device *spi,
1331 struct spi_transfer *xfer)
1332{
1333 struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller);
1334 struct omap2_mcspi_dma *mcspi_dma =
1335 &mcspi->dma_channels[spi_get_chipselect(spi, 0)];
1336
1337 if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx)
1338 return false;
1339
1340 if (spi_controller_is_target(ctlr))
1341 return true;
1342
1343 ctlr->dma_rx = mcspi_dma->dma_rx;
1344 ctlr->dma_tx = mcspi_dma->dma_tx;
1345
1346 return (xfer->len >= DMA_MIN_BYTES);
1347}
1348
1349static size_t omap2_mcspi_max_xfer_size(struct spi_device *spi)
1350{
1351 struct omap2_mcspi *mcspi = spi_controller_get_devdata(spi->controller);
1352 struct omap2_mcspi_dma *mcspi_dma =
1353 &mcspi->dma_channels[spi_get_chipselect(spi, 0)];
1354
1355 if (mcspi->max_xfer_len && mcspi_dma->dma_rx)
1356 return mcspi->max_xfer_len;
1357
1358 return SIZE_MAX;
1359}
1360
1361static int omap2_mcspi_controller_setup(struct omap2_mcspi *mcspi)
1362{
1363 struct spi_controller *ctlr = mcspi->ctlr;
1364 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1365 int ret = 0;
1366
1367 ret = pm_runtime_resume_and_get(mcspi->dev);
1368 if (ret < 0)
1369 return ret;
1370
1371 mcspi_write_reg(ctlr, OMAP2_MCSPI_WAKEUPENABLE,
1372 OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1373 ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1374
1375 omap2_mcspi_set_mode(ctlr);
1376 pm_runtime_mark_last_busy(mcspi->dev);
1377 pm_runtime_put_autosuspend(mcspi->dev);
1378 return 0;
1379}
1380
1381static int omap_mcspi_runtime_suspend(struct device *dev)
1382{
1383 int error;
1384
1385 error = pinctrl_pm_select_idle_state(dev);
1386 if (error)
1387 dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error);
1388
1389 return 0;
1390}
1391
1392/*
1393 * When SPI wake up from off-mode, CS is in activate state. If it was in
1394 * inactive state when driver was suspend, then force it to inactive state at
1395 * wake up.
1396 */
1397static int omap_mcspi_runtime_resume(struct device *dev)
1398{
1399 struct spi_controller *ctlr = dev_get_drvdata(dev);
1400 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
1401 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1402 struct omap2_mcspi_cs *cs;
1403 int error;
1404
1405 error = pinctrl_pm_select_default_state(dev);
1406 if (error)
1407 dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error);
1408
1409 /* McSPI: context restore */
1410 mcspi_write_reg(ctlr, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
1411 mcspi_write_reg(ctlr, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
1412
1413 list_for_each_entry(cs, &ctx->cs, node) {
1414 /*
1415 * We need to toggle CS state for OMAP take this
1416 * change in account.
1417 */
1418 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1419 cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1420 writel_relaxed(cs->chconf0,
1421 cs->base + OMAP2_MCSPI_CHCONF0);
1422 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1423 writel_relaxed(cs->chconf0,
1424 cs->base + OMAP2_MCSPI_CHCONF0);
1425 } else {
1426 writel_relaxed(cs->chconf0,
1427 cs->base + OMAP2_MCSPI_CHCONF0);
1428 }
1429 }
1430
1431 return 0;
1432}
1433
1434static struct omap2_mcspi_platform_config omap2_pdata = {
1435 .regs_offset = 0,
1436};
1437
1438static struct omap2_mcspi_platform_config omap4_pdata = {
1439 .regs_offset = OMAP4_MCSPI_REG_OFFSET,
1440};
1441
1442static struct omap2_mcspi_platform_config am654_pdata = {
1443 .regs_offset = OMAP4_MCSPI_REG_OFFSET,
1444 .max_xfer_len = SZ_4K - 1,
1445};
1446
1447static const struct of_device_id omap_mcspi_of_match[] = {
1448 {
1449 .compatible = "ti,omap2-mcspi",
1450 .data = &omap2_pdata,
1451 },
1452 {
1453 .compatible = "ti,omap4-mcspi",
1454 .data = &omap4_pdata,
1455 },
1456 {
1457 .compatible = "ti,am654-mcspi",
1458 .data = &am654_pdata,
1459 },
1460 { },
1461};
1462MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1463
1464static int omap2_mcspi_probe(struct platform_device *pdev)
1465{
1466 struct spi_controller *ctlr;
1467 const struct omap2_mcspi_platform_config *pdata;
1468 struct omap2_mcspi *mcspi;
1469 struct resource *r;
1470 int status = 0, i;
1471 u32 regs_offset = 0;
1472 struct device_node *node = pdev->dev.of_node;
1473 const struct of_device_id *match;
1474
1475 if (of_property_read_bool(node, "spi-slave"))
1476 ctlr = spi_alloc_target(&pdev->dev, sizeof(*mcspi));
1477 else
1478 ctlr = spi_alloc_host(&pdev->dev, sizeof(*mcspi));
1479 if (!ctlr)
1480 return -ENOMEM;
1481
1482 /* the spi->mode bits understood by this driver: */
1483 ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1484 ctlr->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1485 ctlr->setup = omap2_mcspi_setup;
1486 ctlr->auto_runtime_pm = true;
1487 ctlr->prepare_message = omap2_mcspi_prepare_message;
1488 ctlr->can_dma = omap2_mcspi_can_dma;
1489 ctlr->transfer_one = omap2_mcspi_transfer_one;
1490 ctlr->set_cs = omap2_mcspi_set_cs;
1491 ctlr->cleanup = omap2_mcspi_cleanup;
1492 ctlr->target_abort = omap2_mcspi_target_abort;
1493 ctlr->dev.of_node = node;
1494 ctlr->use_gpio_descriptors = true;
1495
1496 platform_set_drvdata(pdev, ctlr);
1497
1498 mcspi = spi_controller_get_devdata(ctlr);
1499 mcspi->ctlr = ctlr;
1500
1501 match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1502 if (match) {
1503 u32 num_cs = 1; /* default number of chipselect */
1504 pdata = match->data;
1505
1506 of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1507 ctlr->num_chipselect = num_cs;
1508 if (of_property_read_bool(node, "ti,pindir-d0-out-d1-in"))
1509 mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1510 } else {
1511 pdata = dev_get_platdata(&pdev->dev);
1512 ctlr->num_chipselect = pdata->num_cs;
1513 mcspi->pin_dir = pdata->pin_dir;
1514 }
1515 regs_offset = pdata->regs_offset;
1516 if (pdata->max_xfer_len) {
1517 mcspi->max_xfer_len = pdata->max_xfer_len;
1518 ctlr->max_transfer_size = omap2_mcspi_max_xfer_size;
1519 }
1520
1521 mcspi->base = devm_platform_get_and_ioremap_resource(pdev, 0, &r);
1522 if (IS_ERR(mcspi->base)) {
1523 status = PTR_ERR(mcspi->base);
1524 goto free_ctlr;
1525 }
1526 mcspi->phys = r->start + regs_offset;
1527 mcspi->base += regs_offset;
1528
1529 mcspi->dev = &pdev->dev;
1530
1531 INIT_LIST_HEAD(&mcspi->ctx.cs);
1532
1533 mcspi->dma_channels = devm_kcalloc(&pdev->dev, ctlr->num_chipselect,
1534 sizeof(struct omap2_mcspi_dma),
1535 GFP_KERNEL);
1536 if (mcspi->dma_channels == NULL) {
1537 status = -ENOMEM;
1538 goto free_ctlr;
1539 }
1540
1541 for (i = 0; i < ctlr->num_chipselect; i++) {
1542 sprintf(mcspi->dma_channels[i].dma_rx_ch_name, "rx%d", i);
1543 sprintf(mcspi->dma_channels[i].dma_tx_ch_name, "tx%d", i);
1544
1545 status = omap2_mcspi_request_dma(mcspi,
1546 &mcspi->dma_channels[i]);
1547 if (status == -EPROBE_DEFER)
1548 goto free_ctlr;
1549 }
1550
1551 status = platform_get_irq(pdev, 0);
1552 if (status < 0)
1553 goto free_ctlr;
1554 init_completion(&mcspi->txdone);
1555 status = devm_request_irq(&pdev->dev, status,
1556 omap2_mcspi_irq_handler, 0, pdev->name,
1557 mcspi);
1558 if (status) {
1559 dev_err(&pdev->dev, "Cannot request IRQ");
1560 goto free_ctlr;
1561 }
1562
1563 mcspi->ref_clk = devm_clk_get_optional_enabled(&pdev->dev, NULL);
1564 if (IS_ERR(mcspi->ref_clk)) {
1565 status = PTR_ERR(mcspi->ref_clk);
1566 dev_err_probe(&pdev->dev, status, "Failed to get ref_clk");
1567 goto free_ctlr;
1568 }
1569 if (mcspi->ref_clk)
1570 mcspi->ref_clk_hz = clk_get_rate(mcspi->ref_clk);
1571 else
1572 mcspi->ref_clk_hz = OMAP2_MCSPI_MAX_FREQ;
1573 ctlr->max_speed_hz = mcspi->ref_clk_hz;
1574 ctlr->min_speed_hz = mcspi->ref_clk_hz >> 15;
1575
1576 pm_runtime_use_autosuspend(&pdev->dev);
1577 pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1578 pm_runtime_enable(&pdev->dev);
1579
1580 status = omap2_mcspi_controller_setup(mcspi);
1581 if (status < 0)
1582 goto disable_pm;
1583
1584 status = devm_spi_register_controller(&pdev->dev, ctlr);
1585 if (status < 0)
1586 goto disable_pm;
1587
1588 return status;
1589
1590disable_pm:
1591 pm_runtime_dont_use_autosuspend(&pdev->dev);
1592 pm_runtime_put_sync(&pdev->dev);
1593 pm_runtime_disable(&pdev->dev);
1594free_ctlr:
1595 omap2_mcspi_release_dma(ctlr);
1596 spi_controller_put(ctlr);
1597 return status;
1598}
1599
1600static void omap2_mcspi_remove(struct platform_device *pdev)
1601{
1602 struct spi_controller *ctlr = platform_get_drvdata(pdev);
1603 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
1604
1605 omap2_mcspi_release_dma(ctlr);
1606
1607 pm_runtime_dont_use_autosuspend(mcspi->dev);
1608 pm_runtime_put_sync(mcspi->dev);
1609 pm_runtime_disable(&pdev->dev);
1610}
1611
1612/* work with hotplug and coldplug */
1613MODULE_ALIAS("platform:omap2_mcspi");
1614
1615static int __maybe_unused omap2_mcspi_suspend(struct device *dev)
1616{
1617 struct spi_controller *ctlr = dev_get_drvdata(dev);
1618 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
1619 int error;
1620
1621 error = pinctrl_pm_select_sleep_state(dev);
1622 if (error)
1623 dev_warn(mcspi->dev, "%s: failed to set pins: %i\n",
1624 __func__, error);
1625
1626 error = spi_controller_suspend(ctlr);
1627 if (error)
1628 dev_warn(mcspi->dev, "%s: controller suspend failed: %i\n",
1629 __func__, error);
1630
1631 return pm_runtime_force_suspend(dev);
1632}
1633
1634static int __maybe_unused omap2_mcspi_resume(struct device *dev)
1635{
1636 struct spi_controller *ctlr = dev_get_drvdata(dev);
1637 struct omap2_mcspi *mcspi = spi_controller_get_devdata(ctlr);
1638 int error;
1639
1640 error = spi_controller_resume(ctlr);
1641 if (error)
1642 dev_warn(mcspi->dev, "%s: controller resume failed: %i\n",
1643 __func__, error);
1644
1645 return pm_runtime_force_resume(dev);
1646}
1647
1648static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1649 SET_SYSTEM_SLEEP_PM_OPS(omap2_mcspi_suspend,
1650 omap2_mcspi_resume)
1651 .runtime_suspend = omap_mcspi_runtime_suspend,
1652 .runtime_resume = omap_mcspi_runtime_resume,
1653};
1654
1655static struct platform_driver omap2_mcspi_driver = {
1656 .driver = {
1657 .name = "omap2_mcspi",
1658 .pm = &omap2_mcspi_pm_ops,
1659 .of_match_table = omap_mcspi_of_match,
1660 },
1661 .probe = omap2_mcspi_probe,
1662 .remove = omap2_mcspi_remove,
1663};
1664
1665module_platform_driver(omap2_mcspi_driver);
1666MODULE_DESCRIPTION("OMAP2 McSPI controller driver");
1667MODULE_LICENSE("GPL");