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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
19#include <linux/kernel.h>
20#include <linux/interrupt.h>
21#include <linux/module.h>
22#include <linux/device.h>
23#include <linux/delay.h>
24#include <linux/dma-mapping.h>
25#include <linux/dmaengine.h>
26#include <linux/pinctrl/consumer.h>
27#include <linux/platform_device.h>
28#include <linux/err.h>
29#include <linux/clk.h>
30#include <linux/io.h>
31#include <linux/slab.h>
32#include <linux/pm_runtime.h>
33#include <linux/of.h>
34#include <linux/of_device.h>
35#include <linux/gcd.h>
36
37#include <linux/spi/spi.h>
38#include <linux/gpio.h>
39
40#include <linux/platform_data/spi-omap2-mcspi.h>
41
42#define OMAP2_MCSPI_MAX_FREQ 48000000
43#define OMAP2_MCSPI_MAX_DIVIDER 4096
44#define OMAP2_MCSPI_MAX_FIFODEPTH 64
45#define OMAP2_MCSPI_MAX_FIFOWCNT 0xFFFF
46#define SPI_AUTOSUSPEND_TIMEOUT 2000
47
48#define OMAP2_MCSPI_REVISION 0x00
49#define OMAP2_MCSPI_SYSSTATUS 0x14
50#define OMAP2_MCSPI_IRQSTATUS 0x18
51#define OMAP2_MCSPI_IRQENABLE 0x1c
52#define OMAP2_MCSPI_WAKEUPENABLE 0x20
53#define OMAP2_MCSPI_SYST 0x24
54#define OMAP2_MCSPI_MODULCTRL 0x28
55#define OMAP2_MCSPI_XFERLEVEL 0x7c
56
57/* per-channel banks, 0x14 bytes each, first is: */
58#define OMAP2_MCSPI_CHCONF0 0x2c
59#define OMAP2_MCSPI_CHSTAT0 0x30
60#define OMAP2_MCSPI_CHCTRL0 0x34
61#define OMAP2_MCSPI_TX0 0x38
62#define OMAP2_MCSPI_RX0 0x3c
63
64/* per-register bitmasks: */
65#define OMAP2_MCSPI_IRQSTATUS_EOW BIT(17)
66
67#define OMAP2_MCSPI_MODULCTRL_SINGLE BIT(0)
68#define OMAP2_MCSPI_MODULCTRL_MS BIT(2)
69#define OMAP2_MCSPI_MODULCTRL_STEST BIT(3)
70
71#define OMAP2_MCSPI_CHCONF_PHA BIT(0)
72#define OMAP2_MCSPI_CHCONF_POL BIT(1)
73#define OMAP2_MCSPI_CHCONF_CLKD_MASK (0x0f << 2)
74#define OMAP2_MCSPI_CHCONF_EPOL BIT(6)
75#define OMAP2_MCSPI_CHCONF_WL_MASK (0x1f << 7)
76#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY BIT(12)
77#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY BIT(13)
78#define OMAP2_MCSPI_CHCONF_TRM_MASK (0x03 << 12)
79#define OMAP2_MCSPI_CHCONF_DMAW BIT(14)
80#define OMAP2_MCSPI_CHCONF_DMAR BIT(15)
81#define OMAP2_MCSPI_CHCONF_DPE0 BIT(16)
82#define OMAP2_MCSPI_CHCONF_DPE1 BIT(17)
83#define OMAP2_MCSPI_CHCONF_IS BIT(18)
84#define OMAP2_MCSPI_CHCONF_TURBO BIT(19)
85#define OMAP2_MCSPI_CHCONF_FORCE BIT(20)
86#define OMAP2_MCSPI_CHCONF_FFET BIT(27)
87#define OMAP2_MCSPI_CHCONF_FFER BIT(28)
88#define OMAP2_MCSPI_CHCONF_CLKG BIT(29)
89
90#define OMAP2_MCSPI_CHSTAT_RXS BIT(0)
91#define OMAP2_MCSPI_CHSTAT_TXS BIT(1)
92#define OMAP2_MCSPI_CHSTAT_EOT BIT(2)
93#define OMAP2_MCSPI_CHSTAT_TXFFE BIT(3)
94
95#define OMAP2_MCSPI_CHCTRL_EN BIT(0)
96#define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK (0xff << 8)
97
98#define OMAP2_MCSPI_WAKEUPENABLE_WKEN BIT(0)
99
100/* We have 2 DMA channels per CS, one for RX and one for TX */
101struct omap2_mcspi_dma {
102 struct dma_chan *dma_tx;
103 struct dma_chan *dma_rx;
104
105 struct completion dma_tx_completion;
106 struct completion dma_rx_completion;
107
108 char dma_rx_ch_name[14];
109 char dma_tx_ch_name[14];
110};
111
112/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
113 * cache operations; better heuristics consider wordsize and bitrate.
114 */
115#define DMA_MIN_BYTES 160
116
117
118/*
119 * Used for context save and restore, structure members to be updated whenever
120 * corresponding registers are modified.
121 */
122struct omap2_mcspi_regs {
123 u32 modulctrl;
124 u32 wakeupenable;
125 struct list_head cs;
126};
127
128struct omap2_mcspi {
129 struct spi_master *master;
130 /* Virtual base address of the controller */
131 void __iomem *base;
132 unsigned long phys;
133 /* SPI1 has 4 channels, while SPI2 has 2 */
134 struct omap2_mcspi_dma *dma_channels;
135 struct device *dev;
136 struct omap2_mcspi_regs ctx;
137 int fifo_depth;
138 unsigned int pin_dir:1;
139};
140
141struct omap2_mcspi_cs {
142 void __iomem *base;
143 unsigned long phys;
144 int word_len;
145 u16 mode;
146 struct list_head node;
147 /* Context save and restore shadow register */
148 u32 chconf0, chctrl0;
149};
150
151static inline void mcspi_write_reg(struct spi_master *master,
152 int idx, u32 val)
153{
154 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
155
156 writel_relaxed(val, mcspi->base + idx);
157}
158
159static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
160{
161 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
162
163 return readl_relaxed(mcspi->base + idx);
164}
165
166static inline void mcspi_write_cs_reg(const struct spi_device *spi,
167 int idx, u32 val)
168{
169 struct omap2_mcspi_cs *cs = spi->controller_state;
170
171 writel_relaxed(val, cs->base + idx);
172}
173
174static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
175{
176 struct omap2_mcspi_cs *cs = spi->controller_state;
177
178 return readl_relaxed(cs->base + idx);
179}
180
181static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
182{
183 struct omap2_mcspi_cs *cs = spi->controller_state;
184
185 return cs->chconf0;
186}
187
188static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
189{
190 struct omap2_mcspi_cs *cs = spi->controller_state;
191
192 cs->chconf0 = val;
193 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
194 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
195}
196
197static inline int mcspi_bytes_per_word(int word_len)
198{
199 if (word_len <= 8)
200 return 1;
201 else if (word_len <= 16)
202 return 2;
203 else /* word_len <= 32 */
204 return 4;
205}
206
207static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
208 int is_read, int enable)
209{
210 u32 l, rw;
211
212 l = mcspi_cached_chconf0(spi);
213
214 if (is_read) /* 1 is read, 0 write */
215 rw = OMAP2_MCSPI_CHCONF_DMAR;
216 else
217 rw = OMAP2_MCSPI_CHCONF_DMAW;
218
219 if (enable)
220 l |= rw;
221 else
222 l &= ~rw;
223
224 mcspi_write_chconf0(spi, l);
225}
226
227static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
228{
229 struct omap2_mcspi_cs *cs = spi->controller_state;
230 u32 l;
231
232 l = cs->chctrl0;
233 if (enable)
234 l |= OMAP2_MCSPI_CHCTRL_EN;
235 else
236 l &= ~OMAP2_MCSPI_CHCTRL_EN;
237 cs->chctrl0 = l;
238 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
239 /* Flash post-writes */
240 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
241}
242
243static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable)
244{
245 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
246 u32 l;
247
248 /* The controller handles the inverted chip selects
249 * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert
250 * the inversion from the core spi_set_cs function.
251 */
252 if (spi->mode & SPI_CS_HIGH)
253 enable = !enable;
254
255 if (spi->controller_state) {
256 int err = pm_runtime_get_sync(mcspi->dev);
257 if (err < 0) {
258 dev_err(mcspi->dev, "failed to get sync: %d\n", err);
259 return;
260 }
261
262 l = mcspi_cached_chconf0(spi);
263
264 if (enable)
265 l &= ~OMAP2_MCSPI_CHCONF_FORCE;
266 else
267 l |= OMAP2_MCSPI_CHCONF_FORCE;
268
269 mcspi_write_chconf0(spi, l);
270
271 pm_runtime_mark_last_busy(mcspi->dev);
272 pm_runtime_put_autosuspend(mcspi->dev);
273 }
274}
275
276static void omap2_mcspi_set_master_mode(struct spi_master *master)
277{
278 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
279 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
280 u32 l;
281
282 /*
283 * Setup when switching from (reset default) slave mode
284 * to single-channel master mode
285 */
286 l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
287 l &= ~(OMAP2_MCSPI_MODULCTRL_STEST | OMAP2_MCSPI_MODULCTRL_MS);
288 l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
289 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
290
291 ctx->modulctrl = l;
292}
293
294static void omap2_mcspi_set_fifo(const struct spi_device *spi,
295 struct spi_transfer *t, int enable)
296{
297 struct spi_master *master = spi->master;
298 struct omap2_mcspi_cs *cs = spi->controller_state;
299 struct omap2_mcspi *mcspi;
300 unsigned int wcnt;
301 int max_fifo_depth, fifo_depth, bytes_per_word;
302 u32 chconf, xferlevel;
303
304 mcspi = spi_master_get_devdata(master);
305
306 chconf = mcspi_cached_chconf0(spi);
307 if (enable) {
308 bytes_per_word = mcspi_bytes_per_word(cs->word_len);
309 if (t->len % bytes_per_word != 0)
310 goto disable_fifo;
311
312 if (t->rx_buf != NULL && t->tx_buf != NULL)
313 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
314 else
315 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
316
317 fifo_depth = gcd(t->len, max_fifo_depth);
318 if (fifo_depth < 2 || fifo_depth % bytes_per_word != 0)
319 goto disable_fifo;
320
321 wcnt = t->len / bytes_per_word;
322 if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
323 goto disable_fifo;
324
325 xferlevel = wcnt << 16;
326 if (t->rx_buf != NULL) {
327 chconf |= OMAP2_MCSPI_CHCONF_FFER;
328 xferlevel |= (fifo_depth - 1) << 8;
329 }
330 if (t->tx_buf != NULL) {
331 chconf |= OMAP2_MCSPI_CHCONF_FFET;
332 xferlevel |= fifo_depth - 1;
333 }
334
335 mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel);
336 mcspi_write_chconf0(spi, chconf);
337 mcspi->fifo_depth = fifo_depth;
338
339 return;
340 }
341
342disable_fifo:
343 if (t->rx_buf != NULL)
344 chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
345
346 if (t->tx_buf != NULL)
347 chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
348
349 mcspi_write_chconf0(spi, chconf);
350 mcspi->fifo_depth = 0;
351}
352
353static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
354{
355 struct spi_master *spi_cntrl = mcspi->master;
356 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
357 struct omap2_mcspi_cs *cs;
358
359 /* McSPI: context restore */
360 mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
361 mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
362
363 list_for_each_entry(cs, &ctx->cs, node)
364 writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
365}
366
367static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
368{
369 unsigned long timeout;
370
371 timeout = jiffies + msecs_to_jiffies(1000);
372 while (!(readl_relaxed(reg) & bit)) {
373 if (time_after(jiffies, timeout)) {
374 if (!(readl_relaxed(reg) & bit))
375 return -ETIMEDOUT;
376 else
377 return 0;
378 }
379 cpu_relax();
380 }
381 return 0;
382}
383
384static void omap2_mcspi_rx_callback(void *data)
385{
386 struct spi_device *spi = data;
387 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
388 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
389
390 /* We must disable the DMA RX request */
391 omap2_mcspi_set_dma_req(spi, 1, 0);
392
393 complete(&mcspi_dma->dma_rx_completion);
394}
395
396static void omap2_mcspi_tx_callback(void *data)
397{
398 struct spi_device *spi = data;
399 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
400 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
401
402 /* We must disable the DMA TX request */
403 omap2_mcspi_set_dma_req(spi, 0, 0);
404
405 complete(&mcspi_dma->dma_tx_completion);
406}
407
408static void omap2_mcspi_tx_dma(struct spi_device *spi,
409 struct spi_transfer *xfer,
410 struct dma_slave_config cfg)
411{
412 struct omap2_mcspi *mcspi;
413 struct omap2_mcspi_dma *mcspi_dma;
414 unsigned int count;
415
416 mcspi = spi_master_get_devdata(spi->master);
417 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
418 count = xfer->len;
419
420 if (mcspi_dma->dma_tx) {
421 struct dma_async_tx_descriptor *tx;
422
423 dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
424
425 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, xfer->tx_sg.sgl,
426 xfer->tx_sg.nents,
427 DMA_MEM_TO_DEV,
428 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
429 if (tx) {
430 tx->callback = omap2_mcspi_tx_callback;
431 tx->callback_param = spi;
432 dmaengine_submit(tx);
433 } else {
434 /* FIXME: fall back to PIO? */
435 }
436 }
437 dma_async_issue_pending(mcspi_dma->dma_tx);
438 omap2_mcspi_set_dma_req(spi, 0, 1);
439
440}
441
442static unsigned
443omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
444 struct dma_slave_config cfg,
445 unsigned es)
446{
447 struct omap2_mcspi *mcspi;
448 struct omap2_mcspi_dma *mcspi_dma;
449 unsigned int count, transfer_reduction = 0;
450 struct scatterlist *sg_out[2];
451 int nb_sizes = 0, out_mapped_nents[2], ret, x;
452 size_t sizes[2];
453 u32 l;
454 int elements = 0;
455 int word_len, element_count;
456 struct omap2_mcspi_cs *cs = spi->controller_state;
457 mcspi = spi_master_get_devdata(spi->master);
458 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
459 count = xfer->len;
460
461 /*
462 * In the "End-of-Transfer Procedure" section for DMA RX in OMAP35x TRM
463 * it mentions reducing DMA transfer length by one element in master
464 * normal mode.
465 */
466 if (mcspi->fifo_depth == 0)
467 transfer_reduction = es;
468
469 word_len = cs->word_len;
470 l = mcspi_cached_chconf0(spi);
471
472 if (word_len <= 8)
473 element_count = count;
474 else if (word_len <= 16)
475 element_count = count >> 1;
476 else /* word_len <= 32 */
477 element_count = count >> 2;
478
479 if (mcspi_dma->dma_rx) {
480 struct dma_async_tx_descriptor *tx;
481
482 dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
483
484 /*
485 * Reduce DMA transfer length by one more if McSPI is
486 * configured in turbo mode.
487 */
488 if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
489 transfer_reduction += es;
490
491 if (transfer_reduction) {
492 /* Split sgl into two. The second sgl won't be used. */
493 sizes[0] = count - transfer_reduction;
494 sizes[1] = transfer_reduction;
495 nb_sizes = 2;
496 } else {
497 /*
498 * Don't bother splitting the sgl. This essentially
499 * clones the original sgl.
500 */
501 sizes[0] = count;
502 nb_sizes = 1;
503 }
504
505 ret = sg_split(xfer->rx_sg.sgl, xfer->rx_sg.nents,
506 0, nb_sizes,
507 sizes,
508 sg_out, out_mapped_nents,
509 GFP_KERNEL);
510
511 if (ret < 0) {
512 dev_err(&spi->dev, "sg_split failed\n");
513 return 0;
514 }
515
516 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx,
517 sg_out[0],
518 out_mapped_nents[0],
519 DMA_DEV_TO_MEM,
520 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
521 if (tx) {
522 tx->callback = omap2_mcspi_rx_callback;
523 tx->callback_param = spi;
524 dmaengine_submit(tx);
525 } else {
526 /* FIXME: fall back to PIO? */
527 }
528 }
529
530 dma_async_issue_pending(mcspi_dma->dma_rx);
531 omap2_mcspi_set_dma_req(spi, 1, 1);
532
533 wait_for_completion(&mcspi_dma->dma_rx_completion);
534
535 for (x = 0; x < nb_sizes; x++)
536 kfree(sg_out[x]);
537
538 if (mcspi->fifo_depth > 0)
539 return count;
540
541 /*
542 * Due to the DMA transfer length reduction the missing bytes must
543 * be read manually to receive all of the expected data.
544 */
545 omap2_mcspi_set_enable(spi, 0);
546
547 elements = element_count - 1;
548
549 if (l & OMAP2_MCSPI_CHCONF_TURBO) {
550 elements--;
551
552 if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
553 & OMAP2_MCSPI_CHSTAT_RXS)) {
554 u32 w;
555
556 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
557 if (word_len <= 8)
558 ((u8 *)xfer->rx_buf)[elements++] = w;
559 else if (word_len <= 16)
560 ((u16 *)xfer->rx_buf)[elements++] = w;
561 else /* word_len <= 32 */
562 ((u32 *)xfer->rx_buf)[elements++] = w;
563 } else {
564 int bytes_per_word = mcspi_bytes_per_word(word_len);
565 dev_err(&spi->dev, "DMA RX penultimate word empty\n");
566 count -= (bytes_per_word << 1);
567 omap2_mcspi_set_enable(spi, 1);
568 return count;
569 }
570 }
571 if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
572 & OMAP2_MCSPI_CHSTAT_RXS)) {
573 u32 w;
574
575 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
576 if (word_len <= 8)
577 ((u8 *)xfer->rx_buf)[elements] = w;
578 else if (word_len <= 16)
579 ((u16 *)xfer->rx_buf)[elements] = w;
580 else /* word_len <= 32 */
581 ((u32 *)xfer->rx_buf)[elements] = w;
582 } else {
583 dev_err(&spi->dev, "DMA RX last word empty\n");
584 count -= mcspi_bytes_per_word(word_len);
585 }
586 omap2_mcspi_set_enable(spi, 1);
587 return count;
588}
589
590static unsigned
591omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
592{
593 struct omap2_mcspi *mcspi;
594 struct omap2_mcspi_cs *cs = spi->controller_state;
595 struct omap2_mcspi_dma *mcspi_dma;
596 unsigned int count;
597 u32 l;
598 u8 *rx;
599 const u8 *tx;
600 struct dma_slave_config cfg;
601 enum dma_slave_buswidth width;
602 unsigned es;
603 u32 burst;
604 void __iomem *chstat_reg;
605 void __iomem *irqstat_reg;
606 int wait_res;
607
608 mcspi = spi_master_get_devdata(spi->master);
609 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
610 l = mcspi_cached_chconf0(spi);
611
612
613 if (cs->word_len <= 8) {
614 width = DMA_SLAVE_BUSWIDTH_1_BYTE;
615 es = 1;
616 } else if (cs->word_len <= 16) {
617 width = DMA_SLAVE_BUSWIDTH_2_BYTES;
618 es = 2;
619 } else {
620 width = DMA_SLAVE_BUSWIDTH_4_BYTES;
621 es = 4;
622 }
623
624 count = xfer->len;
625 burst = 1;
626
627 if (mcspi->fifo_depth > 0) {
628 if (count > mcspi->fifo_depth)
629 burst = mcspi->fifo_depth / es;
630 else
631 burst = count / es;
632 }
633
634 memset(&cfg, 0, sizeof(cfg));
635 cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
636 cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
637 cfg.src_addr_width = width;
638 cfg.dst_addr_width = width;
639 cfg.src_maxburst = burst;
640 cfg.dst_maxburst = burst;
641
642 rx = xfer->rx_buf;
643 tx = xfer->tx_buf;
644
645 if (tx != NULL)
646 omap2_mcspi_tx_dma(spi, xfer, cfg);
647
648 if (rx != NULL)
649 count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
650
651 if (tx != NULL) {
652 wait_for_completion(&mcspi_dma->dma_tx_completion);
653
654 if (mcspi->fifo_depth > 0) {
655 irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
656
657 if (mcspi_wait_for_reg_bit(irqstat_reg,
658 OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
659 dev_err(&spi->dev, "EOW timed out\n");
660
661 mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
662 OMAP2_MCSPI_IRQSTATUS_EOW);
663 }
664
665 /* for TX_ONLY mode, be sure all words have shifted out */
666 if (rx == NULL) {
667 chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
668 if (mcspi->fifo_depth > 0) {
669 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
670 OMAP2_MCSPI_CHSTAT_TXFFE);
671 if (wait_res < 0)
672 dev_err(&spi->dev, "TXFFE timed out\n");
673 } else {
674 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
675 OMAP2_MCSPI_CHSTAT_TXS);
676 if (wait_res < 0)
677 dev_err(&spi->dev, "TXS timed out\n");
678 }
679 if (wait_res >= 0 &&
680 (mcspi_wait_for_reg_bit(chstat_reg,
681 OMAP2_MCSPI_CHSTAT_EOT) < 0))
682 dev_err(&spi->dev, "EOT timed out\n");
683 }
684 }
685 return count;
686}
687
688static unsigned
689omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
690{
691 struct omap2_mcspi *mcspi;
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 mcspi = spi_master_get_devdata(spi->master);
702 count = xfer->len;
703 c = count;
704 word_len = cs->word_len;
705
706 l = mcspi_cached_chconf0(spi);
707
708 /* We store the pre-calculated register addresses on stack to speed
709 * up the transfer loop. */
710 tx_reg = base + OMAP2_MCSPI_TX0;
711 rx_reg = base + OMAP2_MCSPI_RX0;
712 chstat_reg = base + OMAP2_MCSPI_CHSTAT0;
713
714 if (c < (word_len>>3))
715 return 0;
716
717 if (word_len <= 8) {
718 u8 *rx;
719 const u8 *tx;
720
721 rx = xfer->rx_buf;
722 tx = xfer->tx_buf;
723
724 do {
725 c -= 1;
726 if (tx != NULL) {
727 if (mcspi_wait_for_reg_bit(chstat_reg,
728 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
729 dev_err(&spi->dev, "TXS timed out\n");
730 goto out;
731 }
732 dev_vdbg(&spi->dev, "write-%d %02x\n",
733 word_len, *tx);
734 writel_relaxed(*tx++, tx_reg);
735 }
736 if (rx != NULL) {
737 if (mcspi_wait_for_reg_bit(chstat_reg,
738 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
739 dev_err(&spi->dev, "RXS timed out\n");
740 goto out;
741 }
742
743 if (c == 1 && tx == NULL &&
744 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
745 omap2_mcspi_set_enable(spi, 0);
746 *rx++ = readl_relaxed(rx_reg);
747 dev_vdbg(&spi->dev, "read-%d %02x\n",
748 word_len, *(rx - 1));
749 if (mcspi_wait_for_reg_bit(chstat_reg,
750 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
751 dev_err(&spi->dev,
752 "RXS timed out\n");
753 goto out;
754 }
755 c = 0;
756 } else if (c == 0 && tx == NULL) {
757 omap2_mcspi_set_enable(spi, 0);
758 }
759
760 *rx++ = readl_relaxed(rx_reg);
761 dev_vdbg(&spi->dev, "read-%d %02x\n",
762 word_len, *(rx - 1));
763 }
764 } while (c);
765 } else if (word_len <= 16) {
766 u16 *rx;
767 const u16 *tx;
768
769 rx = xfer->rx_buf;
770 tx = xfer->tx_buf;
771 do {
772 c -= 2;
773 if (tx != NULL) {
774 if (mcspi_wait_for_reg_bit(chstat_reg,
775 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
776 dev_err(&spi->dev, "TXS timed out\n");
777 goto out;
778 }
779 dev_vdbg(&spi->dev, "write-%d %04x\n",
780 word_len, *tx);
781 writel_relaxed(*tx++, tx_reg);
782 }
783 if (rx != NULL) {
784 if (mcspi_wait_for_reg_bit(chstat_reg,
785 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
786 dev_err(&spi->dev, "RXS timed out\n");
787 goto out;
788 }
789
790 if (c == 2 && tx == NULL &&
791 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
792 omap2_mcspi_set_enable(spi, 0);
793 *rx++ = readl_relaxed(rx_reg);
794 dev_vdbg(&spi->dev, "read-%d %04x\n",
795 word_len, *(rx - 1));
796 if (mcspi_wait_for_reg_bit(chstat_reg,
797 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
798 dev_err(&spi->dev,
799 "RXS timed out\n");
800 goto out;
801 }
802 c = 0;
803 } else if (c == 0 && tx == NULL) {
804 omap2_mcspi_set_enable(spi, 0);
805 }
806
807 *rx++ = readl_relaxed(rx_reg);
808 dev_vdbg(&spi->dev, "read-%d %04x\n",
809 word_len, *(rx - 1));
810 }
811 } while (c >= 2);
812 } else if (word_len <= 32) {
813 u32 *rx;
814 const u32 *tx;
815
816 rx = xfer->rx_buf;
817 tx = xfer->tx_buf;
818 do {
819 c -= 4;
820 if (tx != NULL) {
821 if (mcspi_wait_for_reg_bit(chstat_reg,
822 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
823 dev_err(&spi->dev, "TXS timed out\n");
824 goto out;
825 }
826 dev_vdbg(&spi->dev, "write-%d %08x\n",
827 word_len, *tx);
828 writel_relaxed(*tx++, tx_reg);
829 }
830 if (rx != NULL) {
831 if (mcspi_wait_for_reg_bit(chstat_reg,
832 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
833 dev_err(&spi->dev, "RXS timed out\n");
834 goto out;
835 }
836
837 if (c == 4 && tx == NULL &&
838 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
839 omap2_mcspi_set_enable(spi, 0);
840 *rx++ = readl_relaxed(rx_reg);
841 dev_vdbg(&spi->dev, "read-%d %08x\n",
842 word_len, *(rx - 1));
843 if (mcspi_wait_for_reg_bit(chstat_reg,
844 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
845 dev_err(&spi->dev,
846 "RXS timed out\n");
847 goto out;
848 }
849 c = 0;
850 } else if (c == 0 && tx == NULL) {
851 omap2_mcspi_set_enable(spi, 0);
852 }
853
854 *rx++ = readl_relaxed(rx_reg);
855 dev_vdbg(&spi->dev, "read-%d %08x\n",
856 word_len, *(rx - 1));
857 }
858 } while (c >= 4);
859 }
860
861 /* for TX_ONLY mode, be sure all words have shifted out */
862 if (xfer->rx_buf == NULL) {
863 if (mcspi_wait_for_reg_bit(chstat_reg,
864 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
865 dev_err(&spi->dev, "TXS timed out\n");
866 } else if (mcspi_wait_for_reg_bit(chstat_reg,
867 OMAP2_MCSPI_CHSTAT_EOT) < 0)
868 dev_err(&spi->dev, "EOT timed out\n");
869
870 /* disable chan to purge rx datas received in TX_ONLY transfer,
871 * otherwise these rx datas will affect the direct following
872 * RX_ONLY transfer.
873 */
874 omap2_mcspi_set_enable(spi, 0);
875 }
876out:
877 omap2_mcspi_set_enable(spi, 1);
878 return count - c;
879}
880
881static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
882{
883 u32 div;
884
885 for (div = 0; div < 15; div++)
886 if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
887 return div;
888
889 return 15;
890}
891
892/* called only when no transfer is active to this device */
893static int omap2_mcspi_setup_transfer(struct spi_device *spi,
894 struct spi_transfer *t)
895{
896 struct omap2_mcspi_cs *cs = spi->controller_state;
897 struct omap2_mcspi *mcspi;
898 struct spi_master *spi_cntrl;
899 u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
900 u8 word_len = spi->bits_per_word;
901 u32 speed_hz = spi->max_speed_hz;
902
903 mcspi = spi_master_get_devdata(spi->master);
904 spi_cntrl = mcspi->master;
905
906 if (t != NULL && t->bits_per_word)
907 word_len = t->bits_per_word;
908
909 cs->word_len = word_len;
910
911 if (t && t->speed_hz)
912 speed_hz = t->speed_hz;
913
914 speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
915 if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
916 clkd = omap2_mcspi_calc_divisor(speed_hz);
917 speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
918 clkg = 0;
919 } else {
920 div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
921 speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
922 clkd = (div - 1) & 0xf;
923 extclk = (div - 1) >> 4;
924 clkg = OMAP2_MCSPI_CHCONF_CLKG;
925 }
926
927 l = mcspi_cached_chconf0(spi);
928
929 /* standard 4-wire master mode: SCK, MOSI/out, MISO/in, nCS
930 * REVISIT: this controller could support SPI_3WIRE mode.
931 */
932 if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
933 l &= ~OMAP2_MCSPI_CHCONF_IS;
934 l &= ~OMAP2_MCSPI_CHCONF_DPE1;
935 l |= OMAP2_MCSPI_CHCONF_DPE0;
936 } else {
937 l |= OMAP2_MCSPI_CHCONF_IS;
938 l |= OMAP2_MCSPI_CHCONF_DPE1;
939 l &= ~OMAP2_MCSPI_CHCONF_DPE0;
940 }
941
942 /* wordlength */
943 l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
944 l |= (word_len - 1) << 7;
945
946 /* set chipselect polarity; manage with FORCE */
947 if (!(spi->mode & SPI_CS_HIGH))
948 l |= OMAP2_MCSPI_CHCONF_EPOL; /* active-low; normal */
949 else
950 l &= ~OMAP2_MCSPI_CHCONF_EPOL;
951
952 /* set clock divisor */
953 l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
954 l |= clkd << 2;
955
956 /* set clock granularity */
957 l &= ~OMAP2_MCSPI_CHCONF_CLKG;
958 l |= clkg;
959 if (clkg) {
960 cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
961 cs->chctrl0 |= extclk << 8;
962 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
963 }
964
965 /* set SPI mode 0..3 */
966 if (spi->mode & SPI_CPOL)
967 l |= OMAP2_MCSPI_CHCONF_POL;
968 else
969 l &= ~OMAP2_MCSPI_CHCONF_POL;
970 if (spi->mode & SPI_CPHA)
971 l |= OMAP2_MCSPI_CHCONF_PHA;
972 else
973 l &= ~OMAP2_MCSPI_CHCONF_PHA;
974
975 mcspi_write_chconf0(spi, l);
976
977 cs->mode = spi->mode;
978
979 dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
980 speed_hz,
981 (spi->mode & SPI_CPHA) ? "trailing" : "leading",
982 (spi->mode & SPI_CPOL) ? "inverted" : "normal");
983
984 return 0;
985}
986
987/*
988 * Note that we currently allow DMA only if we get a channel
989 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
990 */
991static int omap2_mcspi_request_dma(struct spi_device *spi)
992{
993 struct spi_master *master = spi->master;
994 struct omap2_mcspi *mcspi;
995 struct omap2_mcspi_dma *mcspi_dma;
996 int ret = 0;
997
998 mcspi = spi_master_get_devdata(master);
999 mcspi_dma = mcspi->dma_channels + spi->chip_select;
1000
1001 init_completion(&mcspi_dma->dma_rx_completion);
1002 init_completion(&mcspi_dma->dma_tx_completion);
1003
1004 mcspi_dma->dma_rx = dma_request_chan(&master->dev,
1005 mcspi_dma->dma_rx_ch_name);
1006 if (IS_ERR(mcspi_dma->dma_rx)) {
1007 ret = PTR_ERR(mcspi_dma->dma_rx);
1008 mcspi_dma->dma_rx = NULL;
1009 goto no_dma;
1010 }
1011
1012 mcspi_dma->dma_tx = dma_request_chan(&master->dev,
1013 mcspi_dma->dma_tx_ch_name);
1014 if (IS_ERR(mcspi_dma->dma_tx)) {
1015 ret = PTR_ERR(mcspi_dma->dma_tx);
1016 mcspi_dma->dma_tx = NULL;
1017 dma_release_channel(mcspi_dma->dma_rx);
1018 mcspi_dma->dma_rx = NULL;
1019 }
1020
1021no_dma:
1022 return ret;
1023}
1024
1025static int omap2_mcspi_setup(struct spi_device *spi)
1026{
1027 int ret;
1028 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1029 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1030 struct omap2_mcspi_dma *mcspi_dma;
1031 struct omap2_mcspi_cs *cs = spi->controller_state;
1032
1033 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1034
1035 if (!cs) {
1036 cs = kzalloc(sizeof *cs, GFP_KERNEL);
1037 if (!cs)
1038 return -ENOMEM;
1039 cs->base = mcspi->base + spi->chip_select * 0x14;
1040 cs->phys = mcspi->phys + spi->chip_select * 0x14;
1041 cs->mode = 0;
1042 cs->chconf0 = 0;
1043 cs->chctrl0 = 0;
1044 spi->controller_state = cs;
1045 /* Link this to context save list */
1046 list_add_tail(&cs->node, &ctx->cs);
1047
1048 if (gpio_is_valid(spi->cs_gpio)) {
1049 ret = gpio_request(spi->cs_gpio, dev_name(&spi->dev));
1050 if (ret) {
1051 dev_err(&spi->dev, "failed to request gpio\n");
1052 return ret;
1053 }
1054 gpio_direction_output(spi->cs_gpio,
1055 !(spi->mode & SPI_CS_HIGH));
1056 }
1057 }
1058
1059 if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) {
1060 ret = omap2_mcspi_request_dma(spi);
1061 if (ret)
1062 dev_warn(&spi->dev, "not using DMA for McSPI (%d)\n",
1063 ret);
1064 }
1065
1066 ret = pm_runtime_get_sync(mcspi->dev);
1067 if (ret < 0)
1068 return ret;
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 int omap2_mcspi_transfer_one(struct spi_master *master,
1111 struct spi_device *spi,
1112 struct spi_transfer *t)
1113{
1114
1115 /* We only enable one channel at a time -- the one whose message is
1116 * -- although this controller would gladly
1117 * arbitrate among multiple channels. This corresponds to "single
1118 * channel" master mode. As a side effect, we need to manage the
1119 * chipselect with the FORCE bit ... CS != channel enable.
1120 */
1121
1122 struct omap2_mcspi *mcspi;
1123 struct omap2_mcspi_dma *mcspi_dma;
1124 struct omap2_mcspi_cs *cs;
1125 struct omap2_mcspi_device_config *cd;
1126 int par_override = 0;
1127 int status = 0;
1128 u32 chconf;
1129
1130 mcspi = spi_master_get_devdata(master);
1131 mcspi_dma = mcspi->dma_channels + spi->chip_select;
1132 cs = spi->controller_state;
1133 cd = spi->controller_data;
1134
1135 /*
1136 * The slave driver could have changed spi->mode in which case
1137 * it will be different from cs->mode (the current hardware setup).
1138 * If so, set par_override (even though its not a parity issue) so
1139 * omap2_mcspi_setup_transfer will be called to configure the hardware
1140 * with the correct mode on the first iteration of the loop below.
1141 */
1142 if (spi->mode != cs->mode)
1143 par_override = 1;
1144
1145 omap2_mcspi_set_enable(spi, 0);
1146
1147 if (gpio_is_valid(spi->cs_gpio))
1148 omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH);
1149
1150 if (par_override ||
1151 (t->speed_hz != spi->max_speed_hz) ||
1152 (t->bits_per_word != spi->bits_per_word)) {
1153 par_override = 1;
1154 status = omap2_mcspi_setup_transfer(spi, t);
1155 if (status < 0)
1156 goto out;
1157 if (t->speed_hz == spi->max_speed_hz &&
1158 t->bits_per_word == spi->bits_per_word)
1159 par_override = 0;
1160 }
1161 if (cd && cd->cs_per_word) {
1162 chconf = mcspi->ctx.modulctrl;
1163 chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1164 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1165 mcspi->ctx.modulctrl =
1166 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1167 }
1168
1169 chconf = mcspi_cached_chconf0(spi);
1170 chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1171 chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
1172
1173 if (t->tx_buf == NULL)
1174 chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1175 else if (t->rx_buf == NULL)
1176 chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1177
1178 if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1179 /* Turbo mode is for more than one word */
1180 if (t->len > ((cs->word_len + 7) >> 3))
1181 chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1182 }
1183
1184 mcspi_write_chconf0(spi, chconf);
1185
1186 if (t->len) {
1187 unsigned count;
1188
1189 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1190 master->cur_msg_mapped &&
1191 master->can_dma(master, spi, t))
1192 omap2_mcspi_set_fifo(spi, t, 1);
1193
1194 omap2_mcspi_set_enable(spi, 1);
1195
1196 /* RX_ONLY mode needs dummy data in TX reg */
1197 if (t->tx_buf == NULL)
1198 writel_relaxed(0, cs->base
1199 + OMAP2_MCSPI_TX0);
1200
1201 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1202 master->cur_msg_mapped &&
1203 master->can_dma(master, spi, t))
1204 count = omap2_mcspi_txrx_dma(spi, t);
1205 else
1206 count = omap2_mcspi_txrx_pio(spi, t);
1207
1208 if (count != t->len) {
1209 status = -EIO;
1210 goto out;
1211 }
1212 }
1213
1214 omap2_mcspi_set_enable(spi, 0);
1215
1216 if (mcspi->fifo_depth > 0)
1217 omap2_mcspi_set_fifo(spi, t, 0);
1218
1219out:
1220 /* Restore defaults if they were overriden */
1221 if (par_override) {
1222 par_override = 0;
1223 status = omap2_mcspi_setup_transfer(spi, NULL);
1224 }
1225
1226 if (cd && cd->cs_per_word) {
1227 chconf = mcspi->ctx.modulctrl;
1228 chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1229 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1230 mcspi->ctx.modulctrl =
1231 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1232 }
1233
1234 omap2_mcspi_set_enable(spi, 0);
1235
1236 if (gpio_is_valid(spi->cs_gpio))
1237 omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
1238
1239 if (mcspi->fifo_depth > 0 && t)
1240 omap2_mcspi_set_fifo(spi, t, 0);
1241
1242 return status;
1243}
1244
1245static int omap2_mcspi_prepare_message(struct spi_master *master,
1246 struct spi_message *msg)
1247{
1248 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1249 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1250 struct omap2_mcspi_cs *cs;
1251
1252 /* Only a single channel can have the FORCE bit enabled
1253 * in its chconf0 register.
1254 * Scan all channels and disable them except the current one.
1255 * A FORCE can remain from a last transfer having cs_change enabled
1256 */
1257 list_for_each_entry(cs, &ctx->cs, node) {
1258 if (msg->spi->controller_state == cs)
1259 continue;
1260
1261 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
1262 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1263 writel_relaxed(cs->chconf0,
1264 cs->base + OMAP2_MCSPI_CHCONF0);
1265 readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
1266 }
1267 }
1268
1269 return 0;
1270}
1271
1272static bool omap2_mcspi_can_dma(struct spi_master *master,
1273 struct spi_device *spi,
1274 struct spi_transfer *xfer)
1275{
1276 return (xfer->len >= DMA_MIN_BYTES);
1277}
1278
1279static int omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
1280{
1281 struct spi_master *master = mcspi->master;
1282 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1283 int ret = 0;
1284
1285 ret = pm_runtime_get_sync(mcspi->dev);
1286 if (ret < 0)
1287 return ret;
1288
1289 mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1290 OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1291 ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1292
1293 omap2_mcspi_set_master_mode(master);
1294 pm_runtime_mark_last_busy(mcspi->dev);
1295 pm_runtime_put_autosuspend(mcspi->dev);
1296 return 0;
1297}
1298
1299static int omap_mcspi_runtime_resume(struct device *dev)
1300{
1301 struct omap2_mcspi *mcspi;
1302 struct spi_master *master;
1303
1304 master = dev_get_drvdata(dev);
1305 mcspi = spi_master_get_devdata(master);
1306 omap2_mcspi_restore_ctx(mcspi);
1307
1308 return 0;
1309}
1310
1311static struct omap2_mcspi_platform_config omap2_pdata = {
1312 .regs_offset = 0,
1313};
1314
1315static struct omap2_mcspi_platform_config omap4_pdata = {
1316 .regs_offset = OMAP4_MCSPI_REG_OFFSET,
1317};
1318
1319static const struct of_device_id omap_mcspi_of_match[] = {
1320 {
1321 .compatible = "ti,omap2-mcspi",
1322 .data = &omap2_pdata,
1323 },
1324 {
1325 .compatible = "ti,omap4-mcspi",
1326 .data = &omap4_pdata,
1327 },
1328 { },
1329};
1330MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1331
1332static int omap2_mcspi_probe(struct platform_device *pdev)
1333{
1334 struct spi_master *master;
1335 const struct omap2_mcspi_platform_config *pdata;
1336 struct omap2_mcspi *mcspi;
1337 struct resource *r;
1338 int status = 0, i;
1339 u32 regs_offset = 0;
1340 static int bus_num = 1;
1341 struct device_node *node = pdev->dev.of_node;
1342 const struct of_device_id *match;
1343
1344 master = spi_alloc_master(&pdev->dev, sizeof *mcspi);
1345 if (master == NULL) {
1346 dev_dbg(&pdev->dev, "master allocation failed\n");
1347 return -ENOMEM;
1348 }
1349
1350 /* the spi->mode bits understood by this driver: */
1351 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1352 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1353 master->setup = omap2_mcspi_setup;
1354 master->auto_runtime_pm = true;
1355 master->prepare_message = omap2_mcspi_prepare_message;
1356 master->can_dma = omap2_mcspi_can_dma;
1357 master->transfer_one = omap2_mcspi_transfer_one;
1358 master->set_cs = omap2_mcspi_set_cs;
1359 master->cleanup = omap2_mcspi_cleanup;
1360 master->dev.of_node = node;
1361 master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1362 master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
1363
1364 platform_set_drvdata(pdev, master);
1365
1366 mcspi = spi_master_get_devdata(master);
1367 mcspi->master = master;
1368
1369 match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1370 if (match) {
1371 u32 num_cs = 1; /* default number of chipselect */
1372 pdata = match->data;
1373
1374 of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1375 master->num_chipselect = num_cs;
1376 master->bus_num = bus_num++;
1377 if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1378 mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1379 } else {
1380 pdata = dev_get_platdata(&pdev->dev);
1381 master->num_chipselect = pdata->num_cs;
1382 if (pdev->id != -1)
1383 master->bus_num = pdev->id;
1384 mcspi->pin_dir = pdata->pin_dir;
1385 }
1386 regs_offset = pdata->regs_offset;
1387
1388 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1389 mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1390 if (IS_ERR(mcspi->base)) {
1391 status = PTR_ERR(mcspi->base);
1392 goto free_master;
1393 }
1394 mcspi->phys = r->start + regs_offset;
1395 mcspi->base += regs_offset;
1396
1397 mcspi->dev = &pdev->dev;
1398
1399 INIT_LIST_HEAD(&mcspi->ctx.cs);
1400
1401 mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1402 sizeof(struct omap2_mcspi_dma),
1403 GFP_KERNEL);
1404 if (mcspi->dma_channels == NULL) {
1405 status = -ENOMEM;
1406 goto free_master;
1407 }
1408
1409 for (i = 0; i < master->num_chipselect; i++) {
1410 sprintf(mcspi->dma_channels[i].dma_rx_ch_name, "rx%d", i);
1411 sprintf(mcspi->dma_channels[i].dma_tx_ch_name, "tx%d", i);
1412 }
1413
1414 if (status < 0)
1415 goto free_master;
1416
1417 pm_runtime_use_autosuspend(&pdev->dev);
1418 pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1419 pm_runtime_enable(&pdev->dev);
1420
1421 status = omap2_mcspi_master_setup(mcspi);
1422 if (status < 0)
1423 goto disable_pm;
1424
1425 status = devm_spi_register_master(&pdev->dev, master);
1426 if (status < 0)
1427 goto disable_pm;
1428
1429 return status;
1430
1431disable_pm:
1432 pm_runtime_dont_use_autosuspend(&pdev->dev);
1433 pm_runtime_put_sync(&pdev->dev);
1434 pm_runtime_disable(&pdev->dev);
1435free_master:
1436 spi_master_put(master);
1437 return status;
1438}
1439
1440static int omap2_mcspi_remove(struct platform_device *pdev)
1441{
1442 struct spi_master *master = platform_get_drvdata(pdev);
1443 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1444
1445 pm_runtime_dont_use_autosuspend(mcspi->dev);
1446 pm_runtime_put_sync(mcspi->dev);
1447 pm_runtime_disable(&pdev->dev);
1448
1449 return 0;
1450}
1451
1452/* work with hotplug and coldplug */
1453MODULE_ALIAS("platform:omap2_mcspi");
1454
1455#ifdef CONFIG_SUSPEND
1456/*
1457 * When SPI wake up from off-mode, CS is in activate state. If it was in
1458 * unactive state when driver was suspend, then force it to unactive state at
1459 * wake up.
1460 */
1461static int omap2_mcspi_resume(struct device *dev)
1462{
1463 struct spi_master *master = dev_get_drvdata(dev);
1464 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1465 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1466 struct omap2_mcspi_cs *cs;
1467
1468 pm_runtime_get_sync(mcspi->dev);
1469 list_for_each_entry(cs, &ctx->cs, node) {
1470 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1471 /*
1472 * We need to toggle CS state for OMAP take this
1473 * change in account.
1474 */
1475 cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1476 writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1477 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1478 writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1479 }
1480 }
1481 pm_runtime_mark_last_busy(mcspi->dev);
1482 pm_runtime_put_autosuspend(mcspi->dev);
1483
1484 return pinctrl_pm_select_default_state(dev);
1485}
1486
1487static int omap2_mcspi_suspend(struct device *dev)
1488{
1489 return pinctrl_pm_select_sleep_state(dev);
1490}
1491
1492#else
1493#define omap2_mcspi_suspend NULL
1494#define omap2_mcspi_resume NULL
1495#endif
1496
1497static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1498 .resume = omap2_mcspi_resume,
1499 .suspend = omap2_mcspi_suspend,
1500 .runtime_resume = omap_mcspi_runtime_resume,
1501};
1502
1503static struct platform_driver omap2_mcspi_driver = {
1504 .driver = {
1505 .name = "omap2_mcspi",
1506 .pm = &omap2_mcspi_pm_ops,
1507 .of_match_table = omap_mcspi_of_match,
1508 },
1509 .probe = omap2_mcspi_probe,
1510 .remove = omap2_mcspi_remove,
1511};
1512
1513module_platform_driver(omap2_mcspi_driver);
1514MODULE_LICENSE("GPL");
1/*
2 * OMAP2 McSPI controller driver
3 *
4 * Copyright (C) 2005, 2006 Nokia Corporation
5 * Author: Samuel Ortiz <samuel.ortiz@nokia.com> and
6 * Juha Yrj�l� <juha.yrjola@nokia.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 */
18
19#include <linux/kernel.h>
20#include <linux/interrupt.h>
21#include <linux/module.h>
22#include <linux/device.h>
23#include <linux/delay.h>
24#include <linux/dma-mapping.h>
25#include <linux/dmaengine.h>
26#include <linux/omap-dma.h>
27#include <linux/pinctrl/consumer.h>
28#include <linux/platform_device.h>
29#include <linux/err.h>
30#include <linux/clk.h>
31#include <linux/io.h>
32#include <linux/slab.h>
33#include <linux/pm_runtime.h>
34#include <linux/of.h>
35#include <linux/of_device.h>
36#include <linux/gcd.h>
37
38#include <linux/spi/spi.h>
39#include <linux/gpio.h>
40
41#include <linux/platform_data/spi-omap2-mcspi.h>
42
43#define OMAP2_MCSPI_MAX_FREQ 48000000
44#define OMAP2_MCSPI_MAX_DIVIDER 4096
45#define OMAP2_MCSPI_MAX_FIFODEPTH 64
46#define OMAP2_MCSPI_MAX_FIFOWCNT 0xFFFF
47#define SPI_AUTOSUSPEND_TIMEOUT 2000
48
49#define OMAP2_MCSPI_REVISION 0x00
50#define OMAP2_MCSPI_SYSSTATUS 0x14
51#define OMAP2_MCSPI_IRQSTATUS 0x18
52#define OMAP2_MCSPI_IRQENABLE 0x1c
53#define OMAP2_MCSPI_WAKEUPENABLE 0x20
54#define OMAP2_MCSPI_SYST 0x24
55#define OMAP2_MCSPI_MODULCTRL 0x28
56#define OMAP2_MCSPI_XFERLEVEL 0x7c
57
58/* per-channel banks, 0x14 bytes each, first is: */
59#define OMAP2_MCSPI_CHCONF0 0x2c
60#define OMAP2_MCSPI_CHSTAT0 0x30
61#define OMAP2_MCSPI_CHCTRL0 0x34
62#define OMAP2_MCSPI_TX0 0x38
63#define OMAP2_MCSPI_RX0 0x3c
64
65/* per-register bitmasks: */
66#define OMAP2_MCSPI_IRQSTATUS_EOW BIT(17)
67
68#define OMAP2_MCSPI_MODULCTRL_SINGLE BIT(0)
69#define OMAP2_MCSPI_MODULCTRL_MS BIT(2)
70#define OMAP2_MCSPI_MODULCTRL_STEST BIT(3)
71
72#define OMAP2_MCSPI_CHCONF_PHA BIT(0)
73#define OMAP2_MCSPI_CHCONF_POL BIT(1)
74#define OMAP2_MCSPI_CHCONF_CLKD_MASK (0x0f << 2)
75#define OMAP2_MCSPI_CHCONF_EPOL BIT(6)
76#define OMAP2_MCSPI_CHCONF_WL_MASK (0x1f << 7)
77#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY BIT(12)
78#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY BIT(13)
79#define OMAP2_MCSPI_CHCONF_TRM_MASK (0x03 << 12)
80#define OMAP2_MCSPI_CHCONF_DMAW BIT(14)
81#define OMAP2_MCSPI_CHCONF_DMAR BIT(15)
82#define OMAP2_MCSPI_CHCONF_DPE0 BIT(16)
83#define OMAP2_MCSPI_CHCONF_DPE1 BIT(17)
84#define OMAP2_MCSPI_CHCONF_IS BIT(18)
85#define OMAP2_MCSPI_CHCONF_TURBO BIT(19)
86#define OMAP2_MCSPI_CHCONF_FORCE BIT(20)
87#define OMAP2_MCSPI_CHCONF_FFET BIT(27)
88#define OMAP2_MCSPI_CHCONF_FFER BIT(28)
89#define OMAP2_MCSPI_CHCONF_CLKG BIT(29)
90
91#define OMAP2_MCSPI_CHSTAT_RXS BIT(0)
92#define OMAP2_MCSPI_CHSTAT_TXS BIT(1)
93#define OMAP2_MCSPI_CHSTAT_EOT BIT(2)
94#define OMAP2_MCSPI_CHSTAT_TXFFE BIT(3)
95
96#define OMAP2_MCSPI_CHCTRL_EN BIT(0)
97#define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK (0xff << 8)
98
99#define OMAP2_MCSPI_WAKEUPENABLE_WKEN BIT(0)
100
101/* We have 2 DMA channels per CS, one for RX and one for TX */
102struct omap2_mcspi_dma {
103 struct dma_chan *dma_tx;
104 struct dma_chan *dma_rx;
105
106 int dma_tx_sync_dev;
107 int dma_rx_sync_dev;
108
109 struct completion dma_tx_completion;
110 struct completion dma_rx_completion;
111
112 char dma_rx_ch_name[14];
113 char dma_tx_ch_name[14];
114};
115
116/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
117 * cache operations; better heuristics consider wordsize and bitrate.
118 */
119#define DMA_MIN_BYTES 160
120
121
122/*
123 * Used for context save and restore, structure members to be updated whenever
124 * corresponding registers are modified.
125 */
126struct omap2_mcspi_regs {
127 u32 modulctrl;
128 u32 wakeupenable;
129 struct list_head cs;
130};
131
132struct omap2_mcspi {
133 struct spi_master *master;
134 /* Virtual base address of the controller */
135 void __iomem *base;
136 unsigned long phys;
137 /* SPI1 has 4 channels, while SPI2 has 2 */
138 struct omap2_mcspi_dma *dma_channels;
139 struct device *dev;
140 struct omap2_mcspi_regs ctx;
141 int fifo_depth;
142 unsigned int pin_dir:1;
143};
144
145struct omap2_mcspi_cs {
146 void __iomem *base;
147 unsigned long phys;
148 int word_len;
149 u16 mode;
150 struct list_head node;
151 /* Context save and restore shadow register */
152 u32 chconf0, chctrl0;
153};
154
155static inline void mcspi_write_reg(struct spi_master *master,
156 int idx, u32 val)
157{
158 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
159
160 writel_relaxed(val, mcspi->base + idx);
161}
162
163static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
164{
165 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
166
167 return readl_relaxed(mcspi->base + idx);
168}
169
170static inline void mcspi_write_cs_reg(const struct spi_device *spi,
171 int idx, u32 val)
172{
173 struct omap2_mcspi_cs *cs = spi->controller_state;
174
175 writel_relaxed(val, cs->base + idx);
176}
177
178static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
179{
180 struct omap2_mcspi_cs *cs = spi->controller_state;
181
182 return readl_relaxed(cs->base + idx);
183}
184
185static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
186{
187 struct omap2_mcspi_cs *cs = spi->controller_state;
188
189 return cs->chconf0;
190}
191
192static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
193{
194 struct omap2_mcspi_cs *cs = spi->controller_state;
195
196 cs->chconf0 = val;
197 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
198 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
199}
200
201static inline int mcspi_bytes_per_word(int word_len)
202{
203 if (word_len <= 8)
204 return 1;
205 else if (word_len <= 16)
206 return 2;
207 else /* word_len <= 32 */
208 return 4;
209}
210
211static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
212 int is_read, int enable)
213{
214 u32 l, rw;
215
216 l = mcspi_cached_chconf0(spi);
217
218 if (is_read) /* 1 is read, 0 write */
219 rw = OMAP2_MCSPI_CHCONF_DMAR;
220 else
221 rw = OMAP2_MCSPI_CHCONF_DMAW;
222
223 if (enable)
224 l |= rw;
225 else
226 l &= ~rw;
227
228 mcspi_write_chconf0(spi, l);
229}
230
231static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
232{
233 struct omap2_mcspi_cs *cs = spi->controller_state;
234 u32 l;
235
236 l = cs->chctrl0;
237 if (enable)
238 l |= OMAP2_MCSPI_CHCTRL_EN;
239 else
240 l &= ~OMAP2_MCSPI_CHCTRL_EN;
241 cs->chctrl0 = l;
242 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
243 /* Flash post-writes */
244 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
245}
246
247static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable)
248{
249 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
250 u32 l;
251
252 /* The controller handles the inverted chip selects
253 * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert
254 * the inversion from the core spi_set_cs function.
255 */
256 if (spi->mode & SPI_CS_HIGH)
257 enable = !enable;
258
259 if (spi->controller_state) {
260 int err = pm_runtime_get_sync(mcspi->dev);
261 if (err < 0) {
262 dev_err(mcspi->dev, "failed to get sync: %d\n", err);
263 return;
264 }
265
266 l = mcspi_cached_chconf0(spi);
267
268 if (enable)
269 l &= ~OMAP2_MCSPI_CHCONF_FORCE;
270 else
271 l |= OMAP2_MCSPI_CHCONF_FORCE;
272
273 mcspi_write_chconf0(spi, l);
274
275 pm_runtime_mark_last_busy(mcspi->dev);
276 pm_runtime_put_autosuspend(mcspi->dev);
277 }
278}
279
280static void omap2_mcspi_set_master_mode(struct spi_master *master)
281{
282 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
283 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
284 u32 l;
285
286 /*
287 * Setup when switching from (reset default) slave mode
288 * to single-channel master mode
289 */
290 l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
291 l &= ~(OMAP2_MCSPI_MODULCTRL_STEST | OMAP2_MCSPI_MODULCTRL_MS);
292 l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
293 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
294
295 ctx->modulctrl = l;
296}
297
298static void omap2_mcspi_set_fifo(const struct spi_device *spi,
299 struct spi_transfer *t, int enable)
300{
301 struct spi_master *master = spi->master;
302 struct omap2_mcspi_cs *cs = spi->controller_state;
303 struct omap2_mcspi *mcspi;
304 unsigned int wcnt;
305 int max_fifo_depth, fifo_depth, bytes_per_word;
306 u32 chconf, xferlevel;
307
308 mcspi = spi_master_get_devdata(master);
309
310 chconf = mcspi_cached_chconf0(spi);
311 if (enable) {
312 bytes_per_word = mcspi_bytes_per_word(cs->word_len);
313 if (t->len % bytes_per_word != 0)
314 goto disable_fifo;
315
316 if (t->rx_buf != NULL && t->tx_buf != NULL)
317 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
318 else
319 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
320
321 fifo_depth = gcd(t->len, max_fifo_depth);
322 if (fifo_depth < 2 || fifo_depth % bytes_per_word != 0)
323 goto disable_fifo;
324
325 wcnt = t->len / bytes_per_word;
326 if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
327 goto disable_fifo;
328
329 xferlevel = wcnt << 16;
330 if (t->rx_buf != NULL) {
331 chconf |= OMAP2_MCSPI_CHCONF_FFER;
332 xferlevel |= (fifo_depth - 1) << 8;
333 }
334 if (t->tx_buf != NULL) {
335 chconf |= OMAP2_MCSPI_CHCONF_FFET;
336 xferlevel |= fifo_depth - 1;
337 }
338
339 mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel);
340 mcspi_write_chconf0(spi, chconf);
341 mcspi->fifo_depth = fifo_depth;
342
343 return;
344 }
345
346disable_fifo:
347 if (t->rx_buf != NULL)
348 chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
349
350 if (t->tx_buf != NULL)
351 chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
352
353 mcspi_write_chconf0(spi, chconf);
354 mcspi->fifo_depth = 0;
355}
356
357static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
358{
359 struct spi_master *spi_cntrl = mcspi->master;
360 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
361 struct omap2_mcspi_cs *cs;
362
363 /* McSPI: context restore */
364 mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
365 mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
366
367 list_for_each_entry(cs, &ctx->cs, node)
368 writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
369}
370
371static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
372{
373 unsigned long timeout;
374
375 timeout = jiffies + msecs_to_jiffies(1000);
376 while (!(readl_relaxed(reg) & bit)) {
377 if (time_after(jiffies, timeout)) {
378 if (!(readl_relaxed(reg) & bit))
379 return -ETIMEDOUT;
380 else
381 return 0;
382 }
383 cpu_relax();
384 }
385 return 0;
386}
387
388static void omap2_mcspi_rx_callback(void *data)
389{
390 struct spi_device *spi = data;
391 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
392 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
393
394 /* We must disable the DMA RX request */
395 omap2_mcspi_set_dma_req(spi, 1, 0);
396
397 complete(&mcspi_dma->dma_rx_completion);
398}
399
400static void omap2_mcspi_tx_callback(void *data)
401{
402 struct spi_device *spi = data;
403 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
404 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
405
406 /* We must disable the DMA TX request */
407 omap2_mcspi_set_dma_req(spi, 0, 0);
408
409 complete(&mcspi_dma->dma_tx_completion);
410}
411
412static void omap2_mcspi_tx_dma(struct spi_device *spi,
413 struct spi_transfer *xfer,
414 struct dma_slave_config cfg)
415{
416 struct omap2_mcspi *mcspi;
417 struct omap2_mcspi_dma *mcspi_dma;
418 unsigned int count;
419
420 mcspi = spi_master_get_devdata(spi->master);
421 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
422 count = xfer->len;
423
424 if (mcspi_dma->dma_tx) {
425 struct dma_async_tx_descriptor *tx;
426 struct scatterlist sg;
427
428 dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
429
430 sg_init_table(&sg, 1);
431 sg_dma_address(&sg) = xfer->tx_dma;
432 sg_dma_len(&sg) = xfer->len;
433
434 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, &sg, 1,
435 DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
436 if (tx) {
437 tx->callback = omap2_mcspi_tx_callback;
438 tx->callback_param = spi;
439 dmaengine_submit(tx);
440 } else {
441 /* FIXME: fall back to PIO? */
442 }
443 }
444 dma_async_issue_pending(mcspi_dma->dma_tx);
445 omap2_mcspi_set_dma_req(spi, 0, 1);
446
447}
448
449static unsigned
450omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
451 struct dma_slave_config cfg,
452 unsigned es)
453{
454 struct omap2_mcspi *mcspi;
455 struct omap2_mcspi_dma *mcspi_dma;
456 unsigned int count, dma_count;
457 u32 l;
458 int elements = 0;
459 int word_len, element_count;
460 struct omap2_mcspi_cs *cs = spi->controller_state;
461 mcspi = spi_master_get_devdata(spi->master);
462 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
463 count = xfer->len;
464 dma_count = xfer->len;
465
466 if (mcspi->fifo_depth == 0)
467 dma_count -= es;
468
469 word_len = cs->word_len;
470 l = mcspi_cached_chconf0(spi);
471
472 if (word_len <= 8)
473 element_count = count;
474 else if (word_len <= 16)
475 element_count = count >> 1;
476 else /* word_len <= 32 */
477 element_count = count >> 2;
478
479 if (mcspi_dma->dma_rx) {
480 struct dma_async_tx_descriptor *tx;
481 struct scatterlist sg;
482
483 dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
484
485 if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
486 dma_count -= es;
487
488 sg_init_table(&sg, 1);
489 sg_dma_address(&sg) = xfer->rx_dma;
490 sg_dma_len(&sg) = dma_count;
491
492 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, &sg, 1,
493 DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT |
494 DMA_CTRL_ACK);
495 if (tx) {
496 tx->callback = omap2_mcspi_rx_callback;
497 tx->callback_param = spi;
498 dmaengine_submit(tx);
499 } else {
500 /* FIXME: fall back to PIO? */
501 }
502 }
503
504 dma_async_issue_pending(mcspi_dma->dma_rx);
505 omap2_mcspi_set_dma_req(spi, 1, 1);
506
507 wait_for_completion(&mcspi_dma->dma_rx_completion);
508 dma_unmap_single(mcspi->dev, xfer->rx_dma, count,
509 DMA_FROM_DEVICE);
510
511 if (mcspi->fifo_depth > 0)
512 return count;
513
514 omap2_mcspi_set_enable(spi, 0);
515
516 elements = element_count - 1;
517
518 if (l & OMAP2_MCSPI_CHCONF_TURBO) {
519 elements--;
520
521 if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
522 & OMAP2_MCSPI_CHSTAT_RXS)) {
523 u32 w;
524
525 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
526 if (word_len <= 8)
527 ((u8 *)xfer->rx_buf)[elements++] = w;
528 else if (word_len <= 16)
529 ((u16 *)xfer->rx_buf)[elements++] = w;
530 else /* word_len <= 32 */
531 ((u32 *)xfer->rx_buf)[elements++] = w;
532 } else {
533 int bytes_per_word = mcspi_bytes_per_word(word_len);
534 dev_err(&spi->dev, "DMA RX penultimate word empty\n");
535 count -= (bytes_per_word << 1);
536 omap2_mcspi_set_enable(spi, 1);
537 return count;
538 }
539 }
540 if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
541 & OMAP2_MCSPI_CHSTAT_RXS)) {
542 u32 w;
543
544 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
545 if (word_len <= 8)
546 ((u8 *)xfer->rx_buf)[elements] = w;
547 else if (word_len <= 16)
548 ((u16 *)xfer->rx_buf)[elements] = w;
549 else /* word_len <= 32 */
550 ((u32 *)xfer->rx_buf)[elements] = w;
551 } else {
552 dev_err(&spi->dev, "DMA RX last word empty\n");
553 count -= mcspi_bytes_per_word(word_len);
554 }
555 omap2_mcspi_set_enable(spi, 1);
556 return count;
557}
558
559static unsigned
560omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
561{
562 struct omap2_mcspi *mcspi;
563 struct omap2_mcspi_cs *cs = spi->controller_state;
564 struct omap2_mcspi_dma *mcspi_dma;
565 unsigned int count;
566 u32 l;
567 u8 *rx;
568 const u8 *tx;
569 struct dma_slave_config cfg;
570 enum dma_slave_buswidth width;
571 unsigned es;
572 u32 burst;
573 void __iomem *chstat_reg;
574 void __iomem *irqstat_reg;
575 int wait_res;
576
577 mcspi = spi_master_get_devdata(spi->master);
578 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
579 l = mcspi_cached_chconf0(spi);
580
581
582 if (cs->word_len <= 8) {
583 width = DMA_SLAVE_BUSWIDTH_1_BYTE;
584 es = 1;
585 } else if (cs->word_len <= 16) {
586 width = DMA_SLAVE_BUSWIDTH_2_BYTES;
587 es = 2;
588 } else {
589 width = DMA_SLAVE_BUSWIDTH_4_BYTES;
590 es = 4;
591 }
592
593 count = xfer->len;
594 burst = 1;
595
596 if (mcspi->fifo_depth > 0) {
597 if (count > mcspi->fifo_depth)
598 burst = mcspi->fifo_depth / es;
599 else
600 burst = count / es;
601 }
602
603 memset(&cfg, 0, sizeof(cfg));
604 cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
605 cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
606 cfg.src_addr_width = width;
607 cfg.dst_addr_width = width;
608 cfg.src_maxburst = burst;
609 cfg.dst_maxburst = burst;
610
611 rx = xfer->rx_buf;
612 tx = xfer->tx_buf;
613
614 if (tx != NULL)
615 omap2_mcspi_tx_dma(spi, xfer, cfg);
616
617 if (rx != NULL)
618 count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
619
620 if (tx != NULL) {
621 wait_for_completion(&mcspi_dma->dma_tx_completion);
622 dma_unmap_single(mcspi->dev, xfer->tx_dma, xfer->len,
623 DMA_TO_DEVICE);
624
625 if (mcspi->fifo_depth > 0) {
626 irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
627
628 if (mcspi_wait_for_reg_bit(irqstat_reg,
629 OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
630 dev_err(&spi->dev, "EOW timed out\n");
631
632 mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
633 OMAP2_MCSPI_IRQSTATUS_EOW);
634 }
635
636 /* for TX_ONLY mode, be sure all words have shifted out */
637 if (rx == NULL) {
638 chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
639 if (mcspi->fifo_depth > 0) {
640 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
641 OMAP2_MCSPI_CHSTAT_TXFFE);
642 if (wait_res < 0)
643 dev_err(&spi->dev, "TXFFE timed out\n");
644 } else {
645 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
646 OMAP2_MCSPI_CHSTAT_TXS);
647 if (wait_res < 0)
648 dev_err(&spi->dev, "TXS timed out\n");
649 }
650 if (wait_res >= 0 &&
651 (mcspi_wait_for_reg_bit(chstat_reg,
652 OMAP2_MCSPI_CHSTAT_EOT) < 0))
653 dev_err(&spi->dev, "EOT timed out\n");
654 }
655 }
656 return count;
657}
658
659static unsigned
660omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
661{
662 struct omap2_mcspi *mcspi;
663 struct omap2_mcspi_cs *cs = spi->controller_state;
664 unsigned int count, c;
665 u32 l;
666 void __iomem *base = cs->base;
667 void __iomem *tx_reg;
668 void __iomem *rx_reg;
669 void __iomem *chstat_reg;
670 int word_len;
671
672 mcspi = spi_master_get_devdata(spi->master);
673 count = xfer->len;
674 c = count;
675 word_len = cs->word_len;
676
677 l = mcspi_cached_chconf0(spi);
678
679 /* We store the pre-calculated register addresses on stack to speed
680 * up the transfer loop. */
681 tx_reg = base + OMAP2_MCSPI_TX0;
682 rx_reg = base + OMAP2_MCSPI_RX0;
683 chstat_reg = base + OMAP2_MCSPI_CHSTAT0;
684
685 if (c < (word_len>>3))
686 return 0;
687
688 if (word_len <= 8) {
689 u8 *rx;
690 const u8 *tx;
691
692 rx = xfer->rx_buf;
693 tx = xfer->tx_buf;
694
695 do {
696 c -= 1;
697 if (tx != NULL) {
698 if (mcspi_wait_for_reg_bit(chstat_reg,
699 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
700 dev_err(&spi->dev, "TXS timed out\n");
701 goto out;
702 }
703 dev_vdbg(&spi->dev, "write-%d %02x\n",
704 word_len, *tx);
705 writel_relaxed(*tx++, tx_reg);
706 }
707 if (rx != NULL) {
708 if (mcspi_wait_for_reg_bit(chstat_reg,
709 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
710 dev_err(&spi->dev, "RXS timed out\n");
711 goto out;
712 }
713
714 if (c == 1 && tx == NULL &&
715 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
716 omap2_mcspi_set_enable(spi, 0);
717 *rx++ = readl_relaxed(rx_reg);
718 dev_vdbg(&spi->dev, "read-%d %02x\n",
719 word_len, *(rx - 1));
720 if (mcspi_wait_for_reg_bit(chstat_reg,
721 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
722 dev_err(&spi->dev,
723 "RXS timed out\n");
724 goto out;
725 }
726 c = 0;
727 } else if (c == 0 && tx == NULL) {
728 omap2_mcspi_set_enable(spi, 0);
729 }
730
731 *rx++ = readl_relaxed(rx_reg);
732 dev_vdbg(&spi->dev, "read-%d %02x\n",
733 word_len, *(rx - 1));
734 }
735 } while (c);
736 } else if (word_len <= 16) {
737 u16 *rx;
738 const u16 *tx;
739
740 rx = xfer->rx_buf;
741 tx = xfer->tx_buf;
742 do {
743 c -= 2;
744 if (tx != NULL) {
745 if (mcspi_wait_for_reg_bit(chstat_reg,
746 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
747 dev_err(&spi->dev, "TXS timed out\n");
748 goto out;
749 }
750 dev_vdbg(&spi->dev, "write-%d %04x\n",
751 word_len, *tx);
752 writel_relaxed(*tx++, tx_reg);
753 }
754 if (rx != NULL) {
755 if (mcspi_wait_for_reg_bit(chstat_reg,
756 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
757 dev_err(&spi->dev, "RXS timed out\n");
758 goto out;
759 }
760
761 if (c == 2 && tx == NULL &&
762 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
763 omap2_mcspi_set_enable(spi, 0);
764 *rx++ = readl_relaxed(rx_reg);
765 dev_vdbg(&spi->dev, "read-%d %04x\n",
766 word_len, *(rx - 1));
767 if (mcspi_wait_for_reg_bit(chstat_reg,
768 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
769 dev_err(&spi->dev,
770 "RXS timed out\n");
771 goto out;
772 }
773 c = 0;
774 } else if (c == 0 && tx == NULL) {
775 omap2_mcspi_set_enable(spi, 0);
776 }
777
778 *rx++ = readl_relaxed(rx_reg);
779 dev_vdbg(&spi->dev, "read-%d %04x\n",
780 word_len, *(rx - 1));
781 }
782 } while (c >= 2);
783 } else if (word_len <= 32) {
784 u32 *rx;
785 const u32 *tx;
786
787 rx = xfer->rx_buf;
788 tx = xfer->tx_buf;
789 do {
790 c -= 4;
791 if (tx != NULL) {
792 if (mcspi_wait_for_reg_bit(chstat_reg,
793 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
794 dev_err(&spi->dev, "TXS timed out\n");
795 goto out;
796 }
797 dev_vdbg(&spi->dev, "write-%d %08x\n",
798 word_len, *tx);
799 writel_relaxed(*tx++, tx_reg);
800 }
801 if (rx != NULL) {
802 if (mcspi_wait_for_reg_bit(chstat_reg,
803 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
804 dev_err(&spi->dev, "RXS timed out\n");
805 goto out;
806 }
807
808 if (c == 4 && tx == NULL &&
809 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
810 omap2_mcspi_set_enable(spi, 0);
811 *rx++ = readl_relaxed(rx_reg);
812 dev_vdbg(&spi->dev, "read-%d %08x\n",
813 word_len, *(rx - 1));
814 if (mcspi_wait_for_reg_bit(chstat_reg,
815 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
816 dev_err(&spi->dev,
817 "RXS timed out\n");
818 goto out;
819 }
820 c = 0;
821 } else if (c == 0 && tx == NULL) {
822 omap2_mcspi_set_enable(spi, 0);
823 }
824
825 *rx++ = readl_relaxed(rx_reg);
826 dev_vdbg(&spi->dev, "read-%d %08x\n",
827 word_len, *(rx - 1));
828 }
829 } while (c >= 4);
830 }
831
832 /* for TX_ONLY mode, be sure all words have shifted out */
833 if (xfer->rx_buf == NULL) {
834 if (mcspi_wait_for_reg_bit(chstat_reg,
835 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
836 dev_err(&spi->dev, "TXS timed out\n");
837 } else if (mcspi_wait_for_reg_bit(chstat_reg,
838 OMAP2_MCSPI_CHSTAT_EOT) < 0)
839 dev_err(&spi->dev, "EOT timed out\n");
840
841 /* disable chan to purge rx datas received in TX_ONLY transfer,
842 * otherwise these rx datas will affect the direct following
843 * RX_ONLY transfer.
844 */
845 omap2_mcspi_set_enable(spi, 0);
846 }
847out:
848 omap2_mcspi_set_enable(spi, 1);
849 return count - c;
850}
851
852static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
853{
854 u32 div;
855
856 for (div = 0; div < 15; div++)
857 if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
858 return div;
859
860 return 15;
861}
862
863/* called only when no transfer is active to this device */
864static int omap2_mcspi_setup_transfer(struct spi_device *spi,
865 struct spi_transfer *t)
866{
867 struct omap2_mcspi_cs *cs = spi->controller_state;
868 struct omap2_mcspi *mcspi;
869 struct spi_master *spi_cntrl;
870 u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
871 u8 word_len = spi->bits_per_word;
872 u32 speed_hz = spi->max_speed_hz;
873
874 mcspi = spi_master_get_devdata(spi->master);
875 spi_cntrl = mcspi->master;
876
877 if (t != NULL && t->bits_per_word)
878 word_len = t->bits_per_word;
879
880 cs->word_len = word_len;
881
882 if (t && t->speed_hz)
883 speed_hz = t->speed_hz;
884
885 speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
886 if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
887 clkd = omap2_mcspi_calc_divisor(speed_hz);
888 speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
889 clkg = 0;
890 } else {
891 div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
892 speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
893 clkd = (div - 1) & 0xf;
894 extclk = (div - 1) >> 4;
895 clkg = OMAP2_MCSPI_CHCONF_CLKG;
896 }
897
898 l = mcspi_cached_chconf0(spi);
899
900 /* standard 4-wire master mode: SCK, MOSI/out, MISO/in, nCS
901 * REVISIT: this controller could support SPI_3WIRE mode.
902 */
903 if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
904 l &= ~OMAP2_MCSPI_CHCONF_IS;
905 l &= ~OMAP2_MCSPI_CHCONF_DPE1;
906 l |= OMAP2_MCSPI_CHCONF_DPE0;
907 } else {
908 l |= OMAP2_MCSPI_CHCONF_IS;
909 l |= OMAP2_MCSPI_CHCONF_DPE1;
910 l &= ~OMAP2_MCSPI_CHCONF_DPE0;
911 }
912
913 /* wordlength */
914 l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
915 l |= (word_len - 1) << 7;
916
917 /* set chipselect polarity; manage with FORCE */
918 if (!(spi->mode & SPI_CS_HIGH))
919 l |= OMAP2_MCSPI_CHCONF_EPOL; /* active-low; normal */
920 else
921 l &= ~OMAP2_MCSPI_CHCONF_EPOL;
922
923 /* set clock divisor */
924 l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
925 l |= clkd << 2;
926
927 /* set clock granularity */
928 l &= ~OMAP2_MCSPI_CHCONF_CLKG;
929 l |= clkg;
930 if (clkg) {
931 cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
932 cs->chctrl0 |= extclk << 8;
933 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
934 }
935
936 /* set SPI mode 0..3 */
937 if (spi->mode & SPI_CPOL)
938 l |= OMAP2_MCSPI_CHCONF_POL;
939 else
940 l &= ~OMAP2_MCSPI_CHCONF_POL;
941 if (spi->mode & SPI_CPHA)
942 l |= OMAP2_MCSPI_CHCONF_PHA;
943 else
944 l &= ~OMAP2_MCSPI_CHCONF_PHA;
945
946 mcspi_write_chconf0(spi, l);
947
948 cs->mode = spi->mode;
949
950 dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
951 speed_hz,
952 (spi->mode & SPI_CPHA) ? "trailing" : "leading",
953 (spi->mode & SPI_CPOL) ? "inverted" : "normal");
954
955 return 0;
956}
957
958/*
959 * Note that we currently allow DMA only if we get a channel
960 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
961 */
962static int omap2_mcspi_request_dma(struct spi_device *spi)
963{
964 struct spi_master *master = spi->master;
965 struct omap2_mcspi *mcspi;
966 struct omap2_mcspi_dma *mcspi_dma;
967 dma_cap_mask_t mask;
968 unsigned sig;
969
970 mcspi = spi_master_get_devdata(master);
971 mcspi_dma = mcspi->dma_channels + spi->chip_select;
972
973 init_completion(&mcspi_dma->dma_rx_completion);
974 init_completion(&mcspi_dma->dma_tx_completion);
975
976 dma_cap_zero(mask);
977 dma_cap_set(DMA_SLAVE, mask);
978 sig = mcspi_dma->dma_rx_sync_dev;
979
980 mcspi_dma->dma_rx =
981 dma_request_slave_channel_compat(mask, omap_dma_filter_fn,
982 &sig, &master->dev,
983 mcspi_dma->dma_rx_ch_name);
984 if (!mcspi_dma->dma_rx)
985 goto no_dma;
986
987 sig = mcspi_dma->dma_tx_sync_dev;
988 mcspi_dma->dma_tx =
989 dma_request_slave_channel_compat(mask, omap_dma_filter_fn,
990 &sig, &master->dev,
991 mcspi_dma->dma_tx_ch_name);
992
993 if (!mcspi_dma->dma_tx) {
994 dma_release_channel(mcspi_dma->dma_rx);
995 mcspi_dma->dma_rx = NULL;
996 goto no_dma;
997 }
998
999 return 0;
1000
1001no_dma:
1002 dev_warn(&spi->dev, "not using DMA for McSPI\n");
1003 return -EAGAIN;
1004}
1005
1006static int omap2_mcspi_setup(struct spi_device *spi)
1007{
1008 int ret;
1009 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1010 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1011 struct omap2_mcspi_dma *mcspi_dma;
1012 struct omap2_mcspi_cs *cs = spi->controller_state;
1013
1014 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1015
1016 if (!cs) {
1017 cs = kzalloc(sizeof *cs, GFP_KERNEL);
1018 if (!cs)
1019 return -ENOMEM;
1020 cs->base = mcspi->base + spi->chip_select * 0x14;
1021 cs->phys = mcspi->phys + spi->chip_select * 0x14;
1022 cs->mode = 0;
1023 cs->chconf0 = 0;
1024 cs->chctrl0 = 0;
1025 spi->controller_state = cs;
1026 /* Link this to context save list */
1027 list_add_tail(&cs->node, &ctx->cs);
1028
1029 if (gpio_is_valid(spi->cs_gpio)) {
1030 ret = gpio_request(spi->cs_gpio, dev_name(&spi->dev));
1031 if (ret) {
1032 dev_err(&spi->dev, "failed to request gpio\n");
1033 return ret;
1034 }
1035 gpio_direction_output(spi->cs_gpio,
1036 !(spi->mode & SPI_CS_HIGH));
1037 }
1038 }
1039
1040 if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) {
1041 ret = omap2_mcspi_request_dma(spi);
1042 if (ret < 0 && ret != -EAGAIN)
1043 return ret;
1044 }
1045
1046 ret = pm_runtime_get_sync(mcspi->dev);
1047 if (ret < 0)
1048 return ret;
1049
1050 ret = omap2_mcspi_setup_transfer(spi, NULL);
1051 pm_runtime_mark_last_busy(mcspi->dev);
1052 pm_runtime_put_autosuspend(mcspi->dev);
1053
1054 return ret;
1055}
1056
1057static void omap2_mcspi_cleanup(struct spi_device *spi)
1058{
1059 struct omap2_mcspi *mcspi;
1060 struct omap2_mcspi_dma *mcspi_dma;
1061 struct omap2_mcspi_cs *cs;
1062
1063 mcspi = spi_master_get_devdata(spi->master);
1064
1065 if (spi->controller_state) {
1066 /* Unlink controller state from context save list */
1067 cs = spi->controller_state;
1068 list_del(&cs->node);
1069
1070 kfree(cs);
1071 }
1072
1073 if (spi->chip_select < spi->master->num_chipselect) {
1074 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1075
1076 if (mcspi_dma->dma_rx) {
1077 dma_release_channel(mcspi_dma->dma_rx);
1078 mcspi_dma->dma_rx = NULL;
1079 }
1080 if (mcspi_dma->dma_tx) {
1081 dma_release_channel(mcspi_dma->dma_tx);
1082 mcspi_dma->dma_tx = NULL;
1083 }
1084 }
1085
1086 if (gpio_is_valid(spi->cs_gpio))
1087 gpio_free(spi->cs_gpio);
1088}
1089
1090static int omap2_mcspi_work_one(struct omap2_mcspi *mcspi,
1091 struct spi_device *spi, struct spi_transfer *t)
1092{
1093
1094 /* We only enable one channel at a time -- the one whose message is
1095 * -- although this controller would gladly
1096 * arbitrate among multiple channels. This corresponds to "single
1097 * channel" master mode. As a side effect, we need to manage the
1098 * chipselect with the FORCE bit ... CS != channel enable.
1099 */
1100
1101 struct spi_master *master;
1102 struct omap2_mcspi_dma *mcspi_dma;
1103 struct omap2_mcspi_cs *cs;
1104 struct omap2_mcspi_device_config *cd;
1105 int par_override = 0;
1106 int status = 0;
1107 u32 chconf;
1108
1109 master = spi->master;
1110 mcspi_dma = mcspi->dma_channels + spi->chip_select;
1111 cs = spi->controller_state;
1112 cd = spi->controller_data;
1113
1114 /*
1115 * The slave driver could have changed spi->mode in which case
1116 * it will be different from cs->mode (the current hardware setup).
1117 * If so, set par_override (even though its not a parity issue) so
1118 * omap2_mcspi_setup_transfer will be called to configure the hardware
1119 * with the correct mode on the first iteration of the loop below.
1120 */
1121 if (spi->mode != cs->mode)
1122 par_override = 1;
1123
1124 omap2_mcspi_set_enable(spi, 0);
1125
1126 if (gpio_is_valid(spi->cs_gpio))
1127 omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH);
1128
1129 if (par_override ||
1130 (t->speed_hz != spi->max_speed_hz) ||
1131 (t->bits_per_word != spi->bits_per_word)) {
1132 par_override = 1;
1133 status = omap2_mcspi_setup_transfer(spi, t);
1134 if (status < 0)
1135 goto out;
1136 if (t->speed_hz == spi->max_speed_hz &&
1137 t->bits_per_word == spi->bits_per_word)
1138 par_override = 0;
1139 }
1140 if (cd && cd->cs_per_word) {
1141 chconf = mcspi->ctx.modulctrl;
1142 chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1143 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1144 mcspi->ctx.modulctrl =
1145 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1146 }
1147
1148 chconf = mcspi_cached_chconf0(spi);
1149 chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1150 chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
1151
1152 if (t->tx_buf == NULL)
1153 chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1154 else if (t->rx_buf == NULL)
1155 chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1156
1157 if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1158 /* Turbo mode is for more than one word */
1159 if (t->len > ((cs->word_len + 7) >> 3))
1160 chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1161 }
1162
1163 mcspi_write_chconf0(spi, chconf);
1164
1165 if (t->len) {
1166 unsigned count;
1167
1168 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1169 (t->len >= DMA_MIN_BYTES))
1170 omap2_mcspi_set_fifo(spi, t, 1);
1171
1172 omap2_mcspi_set_enable(spi, 1);
1173
1174 /* RX_ONLY mode needs dummy data in TX reg */
1175 if (t->tx_buf == NULL)
1176 writel_relaxed(0, cs->base
1177 + OMAP2_MCSPI_TX0);
1178
1179 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1180 (t->len >= DMA_MIN_BYTES))
1181 count = omap2_mcspi_txrx_dma(spi, t);
1182 else
1183 count = omap2_mcspi_txrx_pio(spi, t);
1184
1185 if (count != t->len) {
1186 status = -EIO;
1187 goto out;
1188 }
1189 }
1190
1191 omap2_mcspi_set_enable(spi, 0);
1192
1193 if (mcspi->fifo_depth > 0)
1194 omap2_mcspi_set_fifo(spi, t, 0);
1195
1196out:
1197 /* Restore defaults if they were overriden */
1198 if (par_override) {
1199 par_override = 0;
1200 status = omap2_mcspi_setup_transfer(spi, NULL);
1201 }
1202
1203 if (cd && cd->cs_per_word) {
1204 chconf = mcspi->ctx.modulctrl;
1205 chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1206 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1207 mcspi->ctx.modulctrl =
1208 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1209 }
1210
1211 omap2_mcspi_set_enable(spi, 0);
1212
1213 if (gpio_is_valid(spi->cs_gpio))
1214 omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
1215
1216 if (mcspi->fifo_depth > 0 && t)
1217 omap2_mcspi_set_fifo(spi, t, 0);
1218
1219 return status;
1220}
1221
1222static int omap2_mcspi_prepare_message(struct spi_master *master,
1223 struct spi_message *msg)
1224{
1225 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1226 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1227 struct omap2_mcspi_cs *cs;
1228
1229 /* Only a single channel can have the FORCE bit enabled
1230 * in its chconf0 register.
1231 * Scan all channels and disable them except the current one.
1232 * A FORCE can remain from a last transfer having cs_change enabled
1233 */
1234 list_for_each_entry(cs, &ctx->cs, node) {
1235 if (msg->spi->controller_state == cs)
1236 continue;
1237
1238 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
1239 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1240 writel_relaxed(cs->chconf0,
1241 cs->base + OMAP2_MCSPI_CHCONF0);
1242 readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
1243 }
1244 }
1245
1246 return 0;
1247}
1248
1249static int omap2_mcspi_transfer_one(struct spi_master *master,
1250 struct spi_device *spi, struct spi_transfer *t)
1251{
1252 struct omap2_mcspi *mcspi;
1253 struct omap2_mcspi_dma *mcspi_dma;
1254 const void *tx_buf = t->tx_buf;
1255 void *rx_buf = t->rx_buf;
1256 unsigned len = t->len;
1257
1258 mcspi = spi_master_get_devdata(master);
1259 mcspi_dma = mcspi->dma_channels + spi->chip_select;
1260
1261 if ((len && !(rx_buf || tx_buf))) {
1262 dev_dbg(mcspi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
1263 t->speed_hz,
1264 len,
1265 tx_buf ? "tx" : "",
1266 rx_buf ? "rx" : "",
1267 t->bits_per_word);
1268 return -EINVAL;
1269 }
1270
1271 if (len < DMA_MIN_BYTES)
1272 goto skip_dma_map;
1273
1274 if (mcspi_dma->dma_tx && tx_buf != NULL) {
1275 t->tx_dma = dma_map_single(mcspi->dev, (void *) tx_buf,
1276 len, DMA_TO_DEVICE);
1277 if (dma_mapping_error(mcspi->dev, t->tx_dma)) {
1278 dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1279 'T', len);
1280 return -EINVAL;
1281 }
1282 }
1283 if (mcspi_dma->dma_rx && rx_buf != NULL) {
1284 t->rx_dma = dma_map_single(mcspi->dev, rx_buf, t->len,
1285 DMA_FROM_DEVICE);
1286 if (dma_mapping_error(mcspi->dev, t->rx_dma)) {
1287 dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1288 'R', len);
1289 if (tx_buf != NULL)
1290 dma_unmap_single(mcspi->dev, t->tx_dma,
1291 len, DMA_TO_DEVICE);
1292 return -EINVAL;
1293 }
1294 }
1295
1296skip_dma_map:
1297 return omap2_mcspi_work_one(mcspi, spi, t);
1298}
1299
1300static int omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
1301{
1302 struct spi_master *master = mcspi->master;
1303 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1304 int ret = 0;
1305
1306 ret = pm_runtime_get_sync(mcspi->dev);
1307 if (ret < 0)
1308 return ret;
1309
1310 mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1311 OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1312 ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1313
1314 omap2_mcspi_set_master_mode(master);
1315 pm_runtime_mark_last_busy(mcspi->dev);
1316 pm_runtime_put_autosuspend(mcspi->dev);
1317 return 0;
1318}
1319
1320static int omap_mcspi_runtime_resume(struct device *dev)
1321{
1322 struct omap2_mcspi *mcspi;
1323 struct spi_master *master;
1324
1325 master = dev_get_drvdata(dev);
1326 mcspi = spi_master_get_devdata(master);
1327 omap2_mcspi_restore_ctx(mcspi);
1328
1329 return 0;
1330}
1331
1332static struct omap2_mcspi_platform_config omap2_pdata = {
1333 .regs_offset = 0,
1334};
1335
1336static struct omap2_mcspi_platform_config omap4_pdata = {
1337 .regs_offset = OMAP4_MCSPI_REG_OFFSET,
1338};
1339
1340static const struct of_device_id omap_mcspi_of_match[] = {
1341 {
1342 .compatible = "ti,omap2-mcspi",
1343 .data = &omap2_pdata,
1344 },
1345 {
1346 .compatible = "ti,omap4-mcspi",
1347 .data = &omap4_pdata,
1348 },
1349 { },
1350};
1351MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1352
1353static int omap2_mcspi_probe(struct platform_device *pdev)
1354{
1355 struct spi_master *master;
1356 const struct omap2_mcspi_platform_config *pdata;
1357 struct omap2_mcspi *mcspi;
1358 struct resource *r;
1359 int status = 0, i;
1360 u32 regs_offset = 0;
1361 static int bus_num = 1;
1362 struct device_node *node = pdev->dev.of_node;
1363 const struct of_device_id *match;
1364
1365 master = spi_alloc_master(&pdev->dev, sizeof *mcspi);
1366 if (master == NULL) {
1367 dev_dbg(&pdev->dev, "master allocation failed\n");
1368 return -ENOMEM;
1369 }
1370
1371 /* the spi->mode bits understood by this driver: */
1372 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1373 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1374 master->setup = omap2_mcspi_setup;
1375 master->auto_runtime_pm = true;
1376 master->prepare_message = omap2_mcspi_prepare_message;
1377 master->transfer_one = omap2_mcspi_transfer_one;
1378 master->set_cs = omap2_mcspi_set_cs;
1379 master->cleanup = omap2_mcspi_cleanup;
1380 master->dev.of_node = node;
1381 master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1382 master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
1383
1384 platform_set_drvdata(pdev, master);
1385
1386 mcspi = spi_master_get_devdata(master);
1387 mcspi->master = master;
1388
1389 match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1390 if (match) {
1391 u32 num_cs = 1; /* default number of chipselect */
1392 pdata = match->data;
1393
1394 of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1395 master->num_chipselect = num_cs;
1396 master->bus_num = bus_num++;
1397 if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1398 mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1399 } else {
1400 pdata = dev_get_platdata(&pdev->dev);
1401 master->num_chipselect = pdata->num_cs;
1402 if (pdev->id != -1)
1403 master->bus_num = pdev->id;
1404 mcspi->pin_dir = pdata->pin_dir;
1405 }
1406 regs_offset = pdata->regs_offset;
1407
1408 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1409 if (r == NULL) {
1410 status = -ENODEV;
1411 goto free_master;
1412 }
1413
1414 r->start += regs_offset;
1415 r->end += regs_offset;
1416 mcspi->phys = r->start;
1417
1418 mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1419 if (IS_ERR(mcspi->base)) {
1420 status = PTR_ERR(mcspi->base);
1421 goto free_master;
1422 }
1423
1424 mcspi->dev = &pdev->dev;
1425
1426 INIT_LIST_HEAD(&mcspi->ctx.cs);
1427
1428 mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1429 sizeof(struct omap2_mcspi_dma),
1430 GFP_KERNEL);
1431 if (mcspi->dma_channels == NULL) {
1432 status = -ENOMEM;
1433 goto free_master;
1434 }
1435
1436 for (i = 0; i < master->num_chipselect; i++) {
1437 char *dma_rx_ch_name = mcspi->dma_channels[i].dma_rx_ch_name;
1438 char *dma_tx_ch_name = mcspi->dma_channels[i].dma_tx_ch_name;
1439 struct resource *dma_res;
1440
1441 sprintf(dma_rx_ch_name, "rx%d", i);
1442 if (!pdev->dev.of_node) {
1443 dma_res =
1444 platform_get_resource_byname(pdev,
1445 IORESOURCE_DMA,
1446 dma_rx_ch_name);
1447 if (!dma_res) {
1448 dev_dbg(&pdev->dev,
1449 "cannot get DMA RX channel\n");
1450 status = -ENODEV;
1451 break;
1452 }
1453
1454 mcspi->dma_channels[i].dma_rx_sync_dev =
1455 dma_res->start;
1456 }
1457 sprintf(dma_tx_ch_name, "tx%d", i);
1458 if (!pdev->dev.of_node) {
1459 dma_res =
1460 platform_get_resource_byname(pdev,
1461 IORESOURCE_DMA,
1462 dma_tx_ch_name);
1463 if (!dma_res) {
1464 dev_dbg(&pdev->dev,
1465 "cannot get DMA TX channel\n");
1466 status = -ENODEV;
1467 break;
1468 }
1469
1470 mcspi->dma_channels[i].dma_tx_sync_dev =
1471 dma_res->start;
1472 }
1473 }
1474
1475 if (status < 0)
1476 goto free_master;
1477
1478 pm_runtime_use_autosuspend(&pdev->dev);
1479 pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1480 pm_runtime_enable(&pdev->dev);
1481
1482 status = omap2_mcspi_master_setup(mcspi);
1483 if (status < 0)
1484 goto disable_pm;
1485
1486 status = devm_spi_register_master(&pdev->dev, master);
1487 if (status < 0)
1488 goto disable_pm;
1489
1490 return status;
1491
1492disable_pm:
1493 pm_runtime_dont_use_autosuspend(&pdev->dev);
1494 pm_runtime_put_sync(&pdev->dev);
1495 pm_runtime_disable(&pdev->dev);
1496free_master:
1497 spi_master_put(master);
1498 return status;
1499}
1500
1501static int omap2_mcspi_remove(struct platform_device *pdev)
1502{
1503 struct spi_master *master = platform_get_drvdata(pdev);
1504 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1505
1506 pm_runtime_dont_use_autosuspend(mcspi->dev);
1507 pm_runtime_put_sync(mcspi->dev);
1508 pm_runtime_disable(&pdev->dev);
1509
1510 return 0;
1511}
1512
1513/* work with hotplug and coldplug */
1514MODULE_ALIAS("platform:omap2_mcspi");
1515
1516#ifdef CONFIG_SUSPEND
1517/*
1518 * When SPI wake up from off-mode, CS is in activate state. If it was in
1519 * unactive state when driver was suspend, then force it to unactive state at
1520 * wake up.
1521 */
1522static int omap2_mcspi_resume(struct device *dev)
1523{
1524 struct spi_master *master = dev_get_drvdata(dev);
1525 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1526 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1527 struct omap2_mcspi_cs *cs;
1528
1529 pm_runtime_get_sync(mcspi->dev);
1530 list_for_each_entry(cs, &ctx->cs, node) {
1531 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1532 /*
1533 * We need to toggle CS state for OMAP take this
1534 * change in account.
1535 */
1536 cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1537 writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1538 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1539 writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1540 }
1541 }
1542 pm_runtime_mark_last_busy(mcspi->dev);
1543 pm_runtime_put_autosuspend(mcspi->dev);
1544
1545 return pinctrl_pm_select_default_state(dev);
1546}
1547
1548static int omap2_mcspi_suspend(struct device *dev)
1549{
1550 return pinctrl_pm_select_sleep_state(dev);
1551}
1552
1553#else
1554#define omap2_mcspi_suspend NULL
1555#define omap2_mcspi_resume NULL
1556#endif
1557
1558static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1559 .resume = omap2_mcspi_resume,
1560 .suspend = omap2_mcspi_suspend,
1561 .runtime_resume = omap_mcspi_runtime_resume,
1562};
1563
1564static struct platform_driver omap2_mcspi_driver = {
1565 .driver = {
1566 .name = "omap2_mcspi",
1567 .pm = &omap2_mcspi_pm_ops,
1568 .of_match_table = omap_mcspi_of_match,
1569 },
1570 .probe = omap2_mcspi_probe,
1571 .remove = omap2_mcspi_remove,
1572};
1573
1574module_platform_driver(omap2_mcspi_driver);
1575MODULE_LICENSE("GPL");