?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
mpt2sas: Fix for system hang when discovery in progress
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / spi / omap2_mcspi.c
blob969cdd2fe124602d1e65c4218190ed3e7d78ccf6
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
38 #include <linux/spi/spi.h>
39
40 #include <plat/dma.h>
41 #include <plat/clock.h>
42 #include <plat/mcspi.h>
43
44 #define OMAP2_MCSPI_MAX_FREQ 48000000
45
46 /* OMAP2 has 3 SPI controllers, while OMAP3 has 4 */
47 #define OMAP2_MCSPI_MAX_CTRL 4
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 */
95 struct 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 struct omap2_mcspi {
113 struct work_struct work;
114 /* lock protects queue and registers */
115 spinlock_t lock;
116 struct list_head msg_queue;
117 struct spi_master *master;
118 /* Virtual base address of the controller */
119 void __iomem *base;
120 unsigned long phys;
121 /* SPI1 has 4 channels, while SPI2 has 2 */
122 struct omap2_mcspi_dma *dma_channels;
123 struct device *dev;
124 };
125
126 struct omap2_mcspi_cs {
127 void __iomem *base;
128 unsigned long phys;
129 int word_len;
130 struct list_head node;
131 /* Context save and restore shadow register */
132 u32 chconf0;
133 };
134
135 /* used for context save and restore, structure members to be updated whenever
136 * corresponding registers are modified.
137 */
138 struct omap2_mcspi_regs {
139 u32 modulctrl;
140 u32 wakeupenable;
141 struct list_head cs;
142 };
143
144 static struct omap2_mcspi_regs omap2_mcspi_ctx[OMAP2_MCSPI_MAX_CTRL];
145
146 static struct workqueue_struct *omap2_mcspi_wq;
147
148 #define MOD_REG_BIT(val, mask, set) do { \
149 if (set) \
150 val |= mask; \
151 else \
152 val &= ~mask; \
153 } while (0)
154
155 static inline void mcspi_write_reg(struct spi_master *master,
156 int idx, u32 val)
157 {
158 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
159
160 __raw_writel(val, mcspi->base + idx);
161 }
162
163 static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
164 {
165 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
166
167 return __raw_readl(mcspi->base + idx);
168 }
169
170 static inline void mcspi_write_cs_reg(const struct spi_device *spi,
171 int idx, u32 val)
172 {
173 struct omap2_mcspi_cs *cs = spi->controller_state;
174
175 __raw_writel(val, cs->base + idx);
176 }
177
178 static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
179 {
180 struct omap2_mcspi_cs *cs = spi->controller_state;
181
182 return __raw_readl(cs->base + idx);
183 }
184
185 static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
186 {
187 struct omap2_mcspi_cs *cs = spi->controller_state;
188
189 return cs->chconf0;
190 }
191
192 static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
193 {
194 struct omap2_mcspi_cs *cs = spi->controller_state;
195
196 cs->chconf0 = val;
197 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
198 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
199 }
200
201 static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
202 int is_read, int enable)
203 {
204 u32 l, rw;
205
206 l = mcspi_cached_chconf0(spi);
207
208 if (is_read) /* 1 is read, 0 write */
209 rw = OMAP2_MCSPI_CHCONF_DMAR;
210 else
211 rw = OMAP2_MCSPI_CHCONF_DMAW;
212
213 MOD_REG_BIT(l, rw, enable);
214 mcspi_write_chconf0(spi, l);
215 }
216
217 static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
218 {
219 u32 l;
220
221 l = enable ? OMAP2_MCSPI_CHCTRL_EN : 0;
222 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, l);
223 /* Flash post-writes */
224 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
225 }
226
227 static void omap2_mcspi_force_cs(struct spi_device *spi, int cs_active)
228 {
229 u32 l;
230
231 l = mcspi_cached_chconf0(spi);
232 MOD_REG_BIT(l, OMAP2_MCSPI_CHCONF_FORCE, cs_active);
233 mcspi_write_chconf0(spi, l);
234 }
235
236 static void omap2_mcspi_set_master_mode(struct spi_master *master)
237 {
238 u32 l;
239
240 /* setup when switching from (reset default) slave mode
241 * to single-channel master mode
242 */
243 l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
244 MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_STEST, 0);
245 MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_MS, 0);
246 MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_SINGLE, 1);
247 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
248
249 omap2_mcspi_ctx[master->bus_num - 1].modulctrl = l;
250 }
251
252 static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
253 {
254 struct spi_master *spi_cntrl;
255 struct omap2_mcspi_cs *cs;
256 spi_cntrl = mcspi->master;
257
258 /* McSPI: context restore */
259 mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL,
260 omap2_mcspi_ctx[spi_cntrl->bus_num - 1].modulctrl);
261
262 mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE,
263 omap2_mcspi_ctx[spi_cntrl->bus_num - 1].wakeupenable);
264
265 list_for_each_entry(cs, &omap2_mcspi_ctx[spi_cntrl->bus_num - 1].cs,
266 node)
267 __raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
268 }
269 static void omap2_mcspi_disable_clocks(struct omap2_mcspi *mcspi)
270 {
271 pm_runtime_put_sync(mcspi->dev);
272 }
273
274 static int omap2_mcspi_enable_clocks(struct omap2_mcspi *mcspi)
275 {
276 return pm_runtime_get_sync(mcspi->dev);
277 }
278
279 static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
280 {
281 unsigned long timeout;
282
283 timeout = jiffies + msecs_to_jiffies(1000);
284 while (!(__raw_readl(reg) & bit)) {
285 if (time_after(jiffies, timeout))
286 return -1;
287 cpu_relax();
288 }
289 return 0;
290 }
291
292 static unsigned
293 omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
294 {
295 struct omap2_mcspi *mcspi;
296 struct omap2_mcspi_cs *cs = spi->controller_state;
297 struct omap2_mcspi_dma *mcspi_dma;
298 unsigned int count, c;
299 unsigned long base, tx_reg, rx_reg;
300 int word_len, data_type, element_count;
301 int elements = 0;
302 u32 l;
303 u8 * rx;
304 const u8 * tx;
305 void __iomem *chstat_reg;
306
307 mcspi = spi_master_get_devdata(spi->master);
308 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
309 l = mcspi_cached_chconf0(spi);
310
311 chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
312
313 count = xfer->len;
314 c = count;
315 word_len = cs->word_len;
316
317 base = cs->phys;
318 tx_reg = base + OMAP2_MCSPI_TX0;
319 rx_reg = base + OMAP2_MCSPI_RX0;
320 rx = xfer->rx_buf;
321 tx = xfer->tx_buf;
322
323 if (word_len <= 8) {
324 data_type = OMAP_DMA_DATA_TYPE_S8;
325 element_count = count;
326 } else if (word_len <= 16) {
327 data_type = OMAP_DMA_DATA_TYPE_S16;
328 element_count = count >> 1;
329 } else /* word_len <= 32 */ {
330 data_type = OMAP_DMA_DATA_TYPE_S32;
331 element_count = count >> 2;
332 }
333
334 if (tx != NULL) {
335 omap_set_dma_transfer_params(mcspi_dma->dma_tx_channel,
336 data_type, element_count, 1,
337 OMAP_DMA_SYNC_ELEMENT,
338 mcspi_dma->dma_tx_sync_dev, 0);
339
340 omap_set_dma_dest_params(mcspi_dma->dma_tx_channel, 0,
341 OMAP_DMA_AMODE_CONSTANT,
342 tx_reg, 0, 0);
343
344 omap_set_dma_src_params(mcspi_dma->dma_tx_channel, 0,
345 OMAP_DMA_AMODE_POST_INC,
346 xfer->tx_dma, 0, 0);
347 }
348
349 if (rx != NULL) {
350 elements = element_count - 1;
351 if (l & OMAP2_MCSPI_CHCONF_TURBO)
352 elements--;
353
354 omap_set_dma_transfer_params(mcspi_dma->dma_rx_channel,
355 data_type, elements, 1,
356 OMAP_DMA_SYNC_ELEMENT,
357 mcspi_dma->dma_rx_sync_dev, 1);
358
359 omap_set_dma_src_params(mcspi_dma->dma_rx_channel, 0,
360 OMAP_DMA_AMODE_CONSTANT,
361 rx_reg, 0, 0);
362
363 omap_set_dma_dest_params(mcspi_dma->dma_rx_channel, 0,
364 OMAP_DMA_AMODE_POST_INC,
365 xfer->rx_dma, 0, 0);
366 }
367
368 if (tx != NULL) {
369 omap_start_dma(mcspi_dma->dma_tx_channel);
370 omap2_mcspi_set_dma_req(spi, 0, 1);
371 }
372
373 if (rx != NULL) {
374 omap_start_dma(mcspi_dma->dma_rx_channel);
375 omap2_mcspi_set_dma_req(spi, 1, 1);
376 }
377
378 if (tx != NULL) {
379 wait_for_completion(&mcspi_dma->dma_tx_completion);
380 dma_unmap_single(&spi->dev, xfer->tx_dma, count, DMA_TO_DEVICE);
381
382 /* for TX_ONLY mode, be sure all words have shifted out */
383 if (rx == NULL) {
384 if (mcspi_wait_for_reg_bit(chstat_reg,
385 OMAP2_MCSPI_CHSTAT_TXS) < 0)
386 dev_err(&spi->dev, "TXS timed out\n");
387 else if (mcspi_wait_for_reg_bit(chstat_reg,
388 OMAP2_MCSPI_CHSTAT_EOT) < 0)
389 dev_err(&spi->dev, "EOT timed out\n");
390 }
391 }
392
393 if (rx != NULL) {
394 wait_for_completion(&mcspi_dma->dma_rx_completion);
395 dma_unmap_single(&spi->dev, xfer->rx_dma, count, DMA_FROM_DEVICE);
396 omap2_mcspi_set_enable(spi, 0);
397
398 if (l & OMAP2_MCSPI_CHCONF_TURBO) {
399
400 if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
401 & OMAP2_MCSPI_CHSTAT_RXS)) {
402 u32 w;
403
404 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
405 if (word_len <= 8)
406 ((u8 *)xfer->rx_buf)[elements++] = w;
407 else if (word_len <= 16)
408 ((u16 *)xfer->rx_buf)[elements++] = w;
409 else /* word_len <= 32 */
410 ((u32 *)xfer->rx_buf)[elements++] = w;
411 } else {
412 dev_err(&spi->dev,
413 "DMA RX penultimate word empty");
414 count -= (word_len <= 8) ? 2 :
415 (word_len <= 16) ? 4 :
416 /* word_len <= 32 */ 8;
417 omap2_mcspi_set_enable(spi, 1);
418 return count;
419 }
420 }
421
422 if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
423 & OMAP2_MCSPI_CHSTAT_RXS)) {
424 u32 w;
425
426 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
427 if (word_len <= 8)
428 ((u8 *)xfer->rx_buf)[elements] = w;
429 else if (word_len <= 16)
430 ((u16 *)xfer->rx_buf)[elements] = w;
431 else /* word_len <= 32 */
432 ((u32 *)xfer->rx_buf)[elements] = w;
433 } else {
434 dev_err(&spi->dev, "DMA RX last word empty");
435 count -= (word_len <= 8) ? 1 :
436 (word_len <= 16) ? 2 :
437 /* word_len <= 32 */ 4;
438 }
439 omap2_mcspi_set_enable(spi, 1);
440 }
441 return count;
442 }
443
444 static unsigned
445 omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
446 {
447 struct omap2_mcspi *mcspi;
448 struct omap2_mcspi_cs *cs = spi->controller_state;
449 unsigned int count, c;
450 u32 l;
451 void __iomem *base = cs->base;
452 void __iomem *tx_reg;
453 void __iomem *rx_reg;
454 void __iomem *chstat_reg;
455 int word_len;
456
457 mcspi = spi_master_get_devdata(spi->master);
458 count = xfer->len;
459 c = count;
460 word_len = cs->word_len;
461
462 l = mcspi_cached_chconf0(spi);
463
464 /* We store the pre-calculated register addresses on stack to speed
465 * up the transfer loop. */
466 tx_reg = base + OMAP2_MCSPI_TX0;
467 rx_reg = base + OMAP2_MCSPI_RX0;
468 chstat_reg = base + OMAP2_MCSPI_CHSTAT0;
469
470 if (c < (word_len>>3))
471 return 0;
472
473 if (word_len <= 8) {
474 u8 *rx;
475 const u8 *tx;
476
477 rx = xfer->rx_buf;
478 tx = xfer->tx_buf;
479
480 do {
481 c -= 1;
482 if (tx != NULL) {
483 if (mcspi_wait_for_reg_bit(chstat_reg,
484 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
485 dev_err(&spi->dev, "TXS timed out\n");
486 goto out;
487 }
488 dev_vdbg(&spi->dev, "write-%d %02x\n",
489 word_len, *tx);
490 __raw_writel(*tx++, tx_reg);
491 }
492 if (rx != NULL) {
493 if (mcspi_wait_for_reg_bit(chstat_reg,
494 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
495 dev_err(&spi->dev, "RXS timed out\n");
496 goto out;
497 }
498
499 if (c == 1 && tx == NULL &&
500 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
501 omap2_mcspi_set_enable(spi, 0);
502 *rx++ = __raw_readl(rx_reg);
503 dev_vdbg(&spi->dev, "read-%d %02x\n",
504 word_len, *(rx - 1));
505 if (mcspi_wait_for_reg_bit(chstat_reg,
506 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
507 dev_err(&spi->dev,
508 "RXS timed out\n");
509 goto out;
510 }
511 c = 0;
512 } else if (c == 0 && tx == NULL) {
513 omap2_mcspi_set_enable(spi, 0);
514 }
515
516 *rx++ = __raw_readl(rx_reg);
517 dev_vdbg(&spi->dev, "read-%d %02x\n",
518 word_len, *(rx - 1));
519 }
520 } while (c);
521 } else if (word_len <= 16) {
522 u16 *rx;
523 const u16 *tx;
524
525 rx = xfer->rx_buf;
526 tx = xfer->tx_buf;
527 do {
528 c -= 2;
529 if (tx != NULL) {
530 if (mcspi_wait_for_reg_bit(chstat_reg,
531 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
532 dev_err(&spi->dev, "TXS timed out\n");
533 goto out;
534 }
535 dev_vdbg(&spi->dev, "write-%d %04x\n",
536 word_len, *tx);
537 __raw_writel(*tx++, tx_reg);
538 }
539 if (rx != NULL) {
540 if (mcspi_wait_for_reg_bit(chstat_reg,
541 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
542 dev_err(&spi->dev, "RXS timed out\n");
543 goto out;
544 }
545
546 if (c == 2 && tx == NULL &&
547 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
548 omap2_mcspi_set_enable(spi, 0);
549 *rx++ = __raw_readl(rx_reg);
550 dev_vdbg(&spi->dev, "read-%d %04x\n",
551 word_len, *(rx - 1));
552 if (mcspi_wait_for_reg_bit(chstat_reg,
553 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
554 dev_err(&spi->dev,
555 "RXS timed out\n");
556 goto out;
557 }
558 c = 0;
559 } else if (c == 0 && tx == NULL) {
560 omap2_mcspi_set_enable(spi, 0);
561 }
562
563 *rx++ = __raw_readl(rx_reg);
564 dev_vdbg(&spi->dev, "read-%d %04x\n",
565 word_len, *(rx - 1));
566 }
567 } while (c >= 2);
568 } else if (word_len <= 32) {
569 u32 *rx;
570 const u32 *tx;
571
572 rx = xfer->rx_buf;
573 tx = xfer->tx_buf;
574 do {
575 c -= 4;
576 if (tx != NULL) {
577 if (mcspi_wait_for_reg_bit(chstat_reg,
578 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
579 dev_err(&spi->dev, "TXS timed out\n");
580 goto out;
581 }
582 dev_vdbg(&spi->dev, "write-%d %08x\n",
583 word_len, *tx);
584 __raw_writel(*tx++, tx_reg);
585 }
586 if (rx != NULL) {
587 if (mcspi_wait_for_reg_bit(chstat_reg,
588 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
589 dev_err(&spi->dev, "RXS timed out\n");
590 goto out;
591 }
592
593 if (c == 4 && tx == NULL &&
594 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
595 omap2_mcspi_set_enable(spi, 0);
596 *rx++ = __raw_readl(rx_reg);
597 dev_vdbg(&spi->dev, "read-%d %08x\n",
598 word_len, *(rx - 1));
599 if (mcspi_wait_for_reg_bit(chstat_reg,
600 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
601 dev_err(&spi->dev,
602 "RXS timed out\n");
603 goto out;
604 }
605 c = 0;
606 } else if (c == 0 && tx == NULL) {
607 omap2_mcspi_set_enable(spi, 0);
608 }
609
610 *rx++ = __raw_readl(rx_reg);
611 dev_vdbg(&spi->dev, "read-%d %08x\n",
612 word_len, *(rx - 1));
613 }
614 } while (c >= 4);
615 }
616
617 /* for TX_ONLY mode, be sure all words have shifted out */
618 if (xfer->rx_buf == NULL) {
619 if (mcspi_wait_for_reg_bit(chstat_reg,
620 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
621 dev_err(&spi->dev, "TXS timed out\n");
622 } else if (mcspi_wait_for_reg_bit(chstat_reg,
623 OMAP2_MCSPI_CHSTAT_EOT) < 0)
624 dev_err(&spi->dev, "EOT timed out\n");
625
626 /* disable chan to purge rx datas received in TX_ONLY transfer,
627 * otherwise these rx datas will affect the direct following
628 * RX_ONLY transfer.
629 */
630 omap2_mcspi_set_enable(spi, 0);
631 }
632 out:
633 omap2_mcspi_set_enable(spi, 1);
634 return count - c;
635 }
636
637 static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
638 {
639 u32 div;
640
641 for (div = 0; div < 15; div++)
642 if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
643 return div;
644
645 return 15;
646 }
647
648 /* called only when no transfer is active to this device */
649 static int omap2_mcspi_setup_transfer(struct spi_device *spi,
650 struct spi_transfer *t)
651 {
652 struct omap2_mcspi_cs *cs = spi->controller_state;
653 struct omap2_mcspi *mcspi;
654 struct spi_master *spi_cntrl;
655 u32 l = 0, div = 0;
656 u8 word_len = spi->bits_per_word;
657 u32 speed_hz = spi->max_speed_hz;
658
659 mcspi = spi_master_get_devdata(spi->master);
660 spi_cntrl = mcspi->master;
661
662 if (t != NULL && t->bits_per_word)
663 word_len = t->bits_per_word;
664
665 cs->word_len = word_len;
666
667 if (t && t->speed_hz)
668 speed_hz = t->speed_hz;
669
670 speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
671 div = omap2_mcspi_calc_divisor(speed_hz);
672
673 l = mcspi_cached_chconf0(spi);
674
675 /* standard 4-wire master mode: SCK, MOSI/out, MISO/in, nCS
676 * REVISIT: this controller could support SPI_3WIRE mode.
677 */
678 l &= ~(OMAP2_MCSPI_CHCONF_IS|OMAP2_MCSPI_CHCONF_DPE1);
679 l |= OMAP2_MCSPI_CHCONF_DPE0;
680
681 /* wordlength */
682 l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
683 l |= (word_len - 1) << 7;
684
685 /* set chipselect polarity; manage with FORCE */
686 if (!(spi->mode & SPI_CS_HIGH))
687 l |= OMAP2_MCSPI_CHCONF_EPOL; /* active-low; normal */
688 else
689 l &= ~OMAP2_MCSPI_CHCONF_EPOL;
690
691 /* set clock divisor */
692 l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
693 l |= div << 2;
694
695 /* set SPI mode 0..3 */
696 if (spi->mode & SPI_CPOL)
697 l |= OMAP2_MCSPI_CHCONF_POL;
698 else
699 l &= ~OMAP2_MCSPI_CHCONF_POL;
700 if (spi->mode & SPI_CPHA)
701 l |= OMAP2_MCSPI_CHCONF_PHA;
702 else
703 l &= ~OMAP2_MCSPI_CHCONF_PHA;
704
705 mcspi_write_chconf0(spi, l);
706
707 dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
708 OMAP2_MCSPI_MAX_FREQ >> div,
709 (spi->mode & SPI_CPHA) ? "trailing" : "leading",
710 (spi->mode & SPI_CPOL) ? "inverted" : "normal");
711
712 return 0;
713 }
714
715 static void omap2_mcspi_dma_rx_callback(int lch, u16 ch_status, void *data)
716 {
717 struct spi_device *spi = data;
718 struct omap2_mcspi *mcspi;
719 struct omap2_mcspi_dma *mcspi_dma;
720
721 mcspi = spi_master_get_devdata(spi->master);
722 mcspi_dma = &(mcspi->dma_channels[spi->chip_select]);
723
724 complete(&mcspi_dma->dma_rx_completion);
725
726 /* We must disable the DMA RX request */
727 omap2_mcspi_set_dma_req(spi, 1, 0);
728 }
729
730 static void omap2_mcspi_dma_tx_callback(int lch, u16 ch_status, void *data)
731 {
732 struct spi_device *spi = data;
733 struct omap2_mcspi *mcspi;
734 struct omap2_mcspi_dma *mcspi_dma;
735
736 mcspi = spi_master_get_devdata(spi->master);
737 mcspi_dma = &(mcspi->dma_channels[spi->chip_select]);
738
739 complete(&mcspi_dma->dma_tx_completion);
740
741 /* We must disable the DMA TX request */
742 omap2_mcspi_set_dma_req(spi, 0, 0);
743 }
744
745 static int omap2_mcspi_request_dma(struct spi_device *spi)
746 {
747 struct spi_master *master = spi->master;
748 struct omap2_mcspi *mcspi;
749 struct omap2_mcspi_dma *mcspi_dma;
750
751 mcspi = spi_master_get_devdata(master);
752 mcspi_dma = mcspi->dma_channels + spi->chip_select;
753
754 if (omap_request_dma(mcspi_dma->dma_rx_sync_dev, "McSPI RX",
755 omap2_mcspi_dma_rx_callback, spi,
756 &mcspi_dma->dma_rx_channel)) {
757 dev_err(&spi->dev, "no RX DMA channel for McSPI\n");
758 return -EAGAIN;
759 }
760
761 if (omap_request_dma(mcspi_dma->dma_tx_sync_dev, "McSPI TX",
762 omap2_mcspi_dma_tx_callback, spi,
763 &mcspi_dma->dma_tx_channel)) {
764 omap_free_dma(mcspi_dma->dma_rx_channel);
765 mcspi_dma->dma_rx_channel = -1;
766 dev_err(&spi->dev, "no TX DMA channel for McSPI\n");
767 return -EAGAIN;
768 }
769
770 init_completion(&mcspi_dma->dma_rx_completion);
771 init_completion(&mcspi_dma->dma_tx_completion);
772
773 return 0;
774 }
775
776 static int omap2_mcspi_setup(struct spi_device *spi)
777 {
778 int ret;
779 struct omap2_mcspi *mcspi;
780 struct omap2_mcspi_dma *mcspi_dma;
781 struct omap2_mcspi_cs *cs = spi->controller_state;
782
783 if (spi->bits_per_word < 4 || spi->bits_per_word > 32) {
784 dev_dbg(&spi->dev, "setup: unsupported %d bit words\n",
785 spi->bits_per_word);
786 return -EINVAL;
787 }
788
789 mcspi = spi_master_get_devdata(spi->master);
790 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
791
792 if (!cs) {
793 cs = kzalloc(sizeof *cs, GFP_KERNEL);
794 if (!cs)
795 return -ENOMEM;
796 cs->base = mcspi->base + spi->chip_select * 0x14;
797 cs->phys = mcspi->phys + spi->chip_select * 0x14;
798 cs->chconf0 = 0;
799 spi->controller_state = cs;
800 /* Link this to context save list */
801 list_add_tail(&cs->node,
802 &omap2_mcspi_ctx[mcspi->master->bus_num - 1].cs);
803 }
804
805 if (mcspi_dma->dma_rx_channel == -1
806 || mcspi_dma->dma_tx_channel == -1) {
807 ret = omap2_mcspi_request_dma(spi);
808 if (ret < 0)
809 return ret;
810 }
811
812 ret = omap2_mcspi_enable_clocks(mcspi);
813 if (ret < 0)
814 return ret;
815
816 ret = omap2_mcspi_setup_transfer(spi, NULL);
817 omap2_mcspi_disable_clocks(mcspi);
818
819 return ret;
820 }
821
822 static void omap2_mcspi_cleanup(struct spi_device *spi)
823 {
824 struct omap2_mcspi *mcspi;
825 struct omap2_mcspi_dma *mcspi_dma;
826 struct omap2_mcspi_cs *cs;
827
828 mcspi = spi_master_get_devdata(spi->master);
829
830 if (spi->controller_state) {
831 /* Unlink controller state from context save list */
832 cs = spi->controller_state;
833 list_del(&cs->node);
834
835 kfree(spi->controller_state);
836 }
837
838 if (spi->chip_select < spi->master->num_chipselect) {
839 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
840
841 if (mcspi_dma->dma_rx_channel != -1) {
842 omap_free_dma(mcspi_dma->dma_rx_channel);
843 mcspi_dma->dma_rx_channel = -1;
844 }
845 if (mcspi_dma->dma_tx_channel != -1) {
846 omap_free_dma(mcspi_dma->dma_tx_channel);
847 mcspi_dma->dma_tx_channel = -1;
848 }
849 }
850 }
851
852 static void omap2_mcspi_work(struct work_struct *work)
853 {
854 struct omap2_mcspi *mcspi;
855
856 mcspi = container_of(work, struct omap2_mcspi, work);
857
858 if (omap2_mcspi_enable_clocks(mcspi) < 0)
859 return;
860
861 spin_lock_irq(&mcspi->lock);
862
863 /* We only enable one channel at a time -- the one whose message is
864 * at the head of the queue -- although this controller would gladly
865 * arbitrate among multiple channels. This corresponds to "single
866 * channel" master mode. As a side effect, we need to manage the
867 * chipselect with the FORCE bit ... CS != channel enable.
868 */
869 while (!list_empty(&mcspi->msg_queue)) {
870 struct spi_message *m;
871 struct spi_device *spi;
872 struct spi_transfer *t = NULL;
873 int cs_active = 0;
874 struct omap2_mcspi_cs *cs;
875 struct omap2_mcspi_device_config *cd;
876 int par_override = 0;
877 int status = 0;
878 u32 chconf;
879
880 m = container_of(mcspi->msg_queue.next, struct spi_message,
881 queue);
882
883 list_del_init(&m->queue);
884 spin_unlock_irq(&mcspi->lock);
885
886 spi = m->spi;
887 cs = spi->controller_state;
888 cd = spi->controller_data;
889
890 omap2_mcspi_set_enable(spi, 1);
891 list_for_each_entry(t, &m->transfers, transfer_list) {
892 if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) {
893 status = -EINVAL;
894 break;
895 }
896 if (par_override || t->speed_hz || t->bits_per_word) {
897 par_override = 1;
898 status = omap2_mcspi_setup_transfer(spi, t);
899 if (status < 0)
900 break;
901 if (!t->speed_hz && !t->bits_per_word)
902 par_override = 0;
903 }
904
905 if (!cs_active) {
906 omap2_mcspi_force_cs(spi, 1);
907 cs_active = 1;
908 }
909
910 chconf = mcspi_cached_chconf0(spi);
911 chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
912 chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
913
914 if (t->tx_buf == NULL)
915 chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
916 else if (t->rx_buf == NULL)
917 chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
918
919 if (cd && cd->turbo_mode && t->tx_buf == NULL) {
920 /* Turbo mode is for more than one word */
921 if (t->len > ((cs->word_len + 7) >> 3))
922 chconf |= OMAP2_MCSPI_CHCONF_TURBO;
923 }
924
925 mcspi_write_chconf0(spi, chconf);
926
927 if (t->len) {
928 unsigned count;
929
930 /* RX_ONLY mode needs dummy data in TX reg */
931 if (t->tx_buf == NULL)
932 __raw_writel(0, cs->base
933 + OMAP2_MCSPI_TX0);
934
935 if (m->is_dma_mapped || t->len >= DMA_MIN_BYTES)
936 count = omap2_mcspi_txrx_dma(spi, t);
937 else
938 count = omap2_mcspi_txrx_pio(spi, t);
939 m->actual_length += count;
940
941 if (count != t->len) {
942 status = -EIO;
943 break;
944 }
945 }
946
947 if (t->delay_usecs)
948 udelay(t->delay_usecs);
949
950 /* ignore the "leave it on after last xfer" hint */
951 if (t->cs_change) {
952 omap2_mcspi_force_cs(spi, 0);
953 cs_active = 0;
954 }
955 }
956
957 /* Restore defaults if they were overriden */
958 if (par_override) {
959 par_override = 0;
960 status = omap2_mcspi_setup_transfer(spi, NULL);
961 }
962
963 if (cs_active)
964 omap2_mcspi_force_cs(spi, 0);
965
966 omap2_mcspi_set_enable(spi, 0);
967
968 m->status = status;
969 m->complete(m->context);
970
971 spin_lock_irq(&mcspi->lock);
972 }
973
974 spin_unlock_irq(&mcspi->lock);
975
976 omap2_mcspi_disable_clocks(mcspi);
977 }
978
979 static int omap2_mcspi_transfer(struct spi_device *spi, struct spi_message *m)
980 {
981 struct omap2_mcspi *mcspi;
982 unsigned long flags;
983 struct spi_transfer *t;
984
985 m->actual_length = 0;
986 m->status = 0;
987
988 /* reject invalid messages and transfers */
989 if (list_empty(&m->transfers) || !m->complete)
990 return -EINVAL;
991 list_for_each_entry(t, &m->transfers, transfer_list) {
992 const void *tx_buf = t->tx_buf;
993 void *rx_buf = t->rx_buf;
994 unsigned len = t->len;
995
996 if (t->speed_hz > OMAP2_MCSPI_MAX_FREQ
997 || (len && !(rx_buf || tx_buf))
998 || (t->bits_per_word &&
999 ( t->bits_per_word < 4
1000 || t->bits_per_word > 32))) {
1001 dev_dbg(&spi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
1002 t->speed_hz,
1003 len,
1004 tx_buf ? "tx" : "",
1005 rx_buf ? "rx" : "",
1006 t->bits_per_word);
1007 return -EINVAL;
1008 }
1009 if (t->speed_hz && t->speed_hz < (OMAP2_MCSPI_MAX_FREQ >> 15)) {
1010 dev_dbg(&spi->dev, "speed_hz %d below minimum %d Hz\n",
1011 t->speed_hz,
1012 OMAP2_MCSPI_MAX_FREQ >> 15);
1013 return -EINVAL;
1014 }
1015
1016 if (m->is_dma_mapped || len < DMA_MIN_BYTES)
1017 continue;
1018
1019 if (tx_buf != NULL) {
1020 t->tx_dma = dma_map_single(&spi->dev, (void *) tx_buf,
1021 len, DMA_TO_DEVICE);
1022 if (dma_mapping_error(&spi->dev, t->tx_dma)) {
1023 dev_dbg(&spi->dev, "dma %cX %d bytes error\n",
1024 'T', len);
1025 return -EINVAL;
1026 }
1027 }
1028 if (rx_buf != NULL) {
1029 t->rx_dma = dma_map_single(&spi->dev, rx_buf, t->len,
1030 DMA_FROM_DEVICE);
1031 if (dma_mapping_error(&spi->dev, t->rx_dma)) {
1032 dev_dbg(&spi->dev, "dma %cX %d bytes error\n",
1033 'R', len);
1034 if (tx_buf != NULL)
1035 dma_unmap_single(&spi->dev, t->tx_dma,
1036 len, DMA_TO_DEVICE);
1037 return -EINVAL;
1038 }
1039 }
1040 }
1041
1042 mcspi = spi_master_get_devdata(spi->master);
1043
1044 spin_lock_irqsave(&mcspi->lock, flags);
1045 list_add_tail(&m->queue, &mcspi->msg_queue);
1046 queue_work(omap2_mcspi_wq, &mcspi->work);
1047 spin_unlock_irqrestore(&mcspi->lock, flags);
1048
1049 return 0;
1050 }
1051
1052 static int __init omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
1053 {
1054 struct spi_master *master = mcspi->master;
1055 u32 tmp;
1056 int ret = 0;
1057
1058 ret = omap2_mcspi_enable_clocks(mcspi);
1059 if (ret < 0)
1060 return ret;
1061
1062 tmp = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1063 mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, tmp);
1064 omap2_mcspi_ctx[master->bus_num - 1].wakeupenable = tmp;
1065
1066 omap2_mcspi_set_master_mode(master);
1067 omap2_mcspi_disable_clocks(mcspi);
1068 return 0;
1069 }
1070
1071 static int omap_mcspi_runtime_resume(struct device *dev)
1072 {
1073 struct omap2_mcspi *mcspi;
1074 struct spi_master *master;
1075
1076 master = dev_get_drvdata(dev);
1077 mcspi = spi_master_get_devdata(master);
1078 omap2_mcspi_restore_ctx(mcspi);
1079
1080 return 0;
1081 }
1082
1083
1084 static int __init omap2_mcspi_probe(struct platform_device *pdev)
1085 {
1086 struct spi_master *master;
1087 struct omap2_mcspi_platform_config *pdata = pdev->dev.platform_data;
1088 struct omap2_mcspi *mcspi;
1089 struct resource *r;
1090 int status = 0, i;
1091
1092 master = spi_alloc_master(&pdev->dev, sizeof *mcspi);
1093 if (master == NULL) {
1094 dev_dbg(&pdev->dev, "master allocation failed\n");
1095 return -ENOMEM;
1096 }
1097
1098 /* the spi->mode bits understood by this driver: */
1099 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1100
1101 if (pdev->id != -1)
1102 master->bus_num = pdev->id;
1103
1104 master->setup = omap2_mcspi_setup;
1105 master->transfer = omap2_mcspi_transfer;
1106 master->cleanup = omap2_mcspi_cleanup;
1107 master->num_chipselect = pdata->num_cs;
1108
1109 dev_set_drvdata(&pdev->dev, master);
1110
1111 mcspi = spi_master_get_devdata(master);
1112 mcspi->master = master;
1113
1114 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1115 if (r == NULL) {
1116 status = -ENODEV;
1117 goto err1;
1118 }
1119 if (!request_mem_region(r->start, (r->end - r->start) + 1,
1120 dev_name(&pdev->dev))) {
1121 status = -EBUSY;
1122 goto err1;
1123 }
1124
1125 r->start += pdata->regs_offset;
1126 r->end += pdata->regs_offset;
1127 mcspi->phys = r->start;
1128 mcspi->base = ioremap(r->start, r->end - r->start + 1);
1129 if (!mcspi->base) {
1130 dev_dbg(&pdev->dev, "can't ioremap MCSPI\n");
1131 status = -ENOMEM;
1132 goto err2;
1133 }
1134
1135 mcspi->dev = &pdev->dev;
1136 INIT_WORK(&mcspi->work, omap2_mcspi_work);
1137
1138 spin_lock_init(&mcspi->lock);
1139 INIT_LIST_HEAD(&mcspi->msg_queue);
1140 INIT_LIST_HEAD(&omap2_mcspi_ctx[master->bus_num - 1].cs);
1141
1142 mcspi->dma_channels = kcalloc(master->num_chipselect,
1143 sizeof(struct omap2_mcspi_dma),
1144 GFP_KERNEL);
1145
1146 if (mcspi->dma_channels == NULL)
1147 goto err2;
1148
1149 for (i = 0; i < master->num_chipselect; i++) {
1150 char dma_ch_name[14];
1151 struct resource *dma_res;
1152
1153 sprintf(dma_ch_name, "rx%d", i);
1154 dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA,
1155 dma_ch_name);
1156 if (!dma_res) {
1157 dev_dbg(&pdev->dev, "cannot get DMA RX channel\n");
1158 status = -ENODEV;
1159 break;
1160 }
1161
1162 mcspi->dma_channels[i].dma_rx_channel = -1;
1163 mcspi->dma_channels[i].dma_rx_sync_dev = dma_res->start;
1164 sprintf(dma_ch_name, "tx%d", i);
1165 dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA,
1166 dma_ch_name);
1167 if (!dma_res) {
1168 dev_dbg(&pdev->dev, "cannot get DMA TX channel\n");
1169 status = -ENODEV;
1170 break;
1171 }
1172
1173 mcspi->dma_channels[i].dma_tx_channel = -1;
1174 mcspi->dma_channels[i].dma_tx_sync_dev = dma_res->start;
1175 }
1176
1177 pm_runtime_enable(&pdev->dev);
1178
1179 if (status || omap2_mcspi_master_setup(mcspi) < 0)
1180 goto err3;
1181
1182 status = spi_register_master(master);
1183 if (status < 0)
1184 goto err4;
1185
1186 return status;
1187
1188 err4:
1189 spi_master_put(master);
1190 err3:
1191 kfree(mcspi->dma_channels);
1192 err2:
1193 release_mem_region(r->start, (r->end - r->start) + 1);
1194 iounmap(mcspi->base);
1195 err1:
1196 return status;
1197 }
1198
1199 static int __exit omap2_mcspi_remove(struct platform_device *pdev)
1200 {
1201 struct spi_master *master;
1202 struct omap2_mcspi *mcspi;
1203 struct omap2_mcspi_dma *dma_channels;
1204 struct resource *r;
1205 void __iomem *base;
1206
1207 master = dev_get_drvdata(&pdev->dev);
1208 mcspi = spi_master_get_devdata(master);
1209 dma_channels = mcspi->dma_channels;
1210
1211 omap2_mcspi_disable_clocks(mcspi);
1212 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1213 release_mem_region(r->start, (r->end - r->start) + 1);
1214
1215 base = mcspi->base;
1216 spi_unregister_master(master);
1217 iounmap(base);
1218 kfree(dma_channels);
1219
1220 return 0;
1221 }
1222
1223 /* work with hotplug and coldplug */
1224 MODULE_ALIAS("platform:omap2_mcspi");
1225
1226 #ifdef CONFIG_SUSPEND
1227 /*
1228 * When SPI wake up from off-mode, CS is in activate state. If it was in
1229 * unactive state when driver was suspend, then force it to unactive state at
1230 * wake up.
1231 */
1232 static int omap2_mcspi_resume(struct device *dev)
1233 {
1234 struct spi_master *master = dev_get_drvdata(dev);
1235 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1236 struct omap2_mcspi_cs *cs;
1237
1238 omap2_mcspi_enable_clocks(mcspi);
1239 list_for_each_entry(cs, &omap2_mcspi_ctx[master->bus_num - 1].cs,
1240 node) {
1241 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1242
1243 /*
1244 * We need to toggle CS state for OMAP take this
1245 * change in account.
1246 */
1247 MOD_REG_BIT(cs->chconf0, OMAP2_MCSPI_CHCONF_FORCE, 1);
1248 __raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1249 MOD_REG_BIT(cs->chconf0, OMAP2_MCSPI_CHCONF_FORCE, 0);
1250 __raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1251 }
1252 }
1253 omap2_mcspi_disable_clocks(mcspi);
1254 return 0;
1255 }
1256 #else
1257 #define omap2_mcspi_resume NULL
1258 #endif
1259
1260 static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1261 .resume = omap2_mcspi_resume,
1262 .runtime_resume = omap_mcspi_runtime_resume,
1263 };
1264
1265 static struct platform_driver omap2_mcspi_driver = {
1266 .driver = {
1267 .name = "omap2_mcspi",
1268 .owner = THIS_MODULE,
1269 .pm = &omap2_mcspi_pm_ops
1270 },
1271 .remove = __exit_p(omap2_mcspi_remove),
1272 };
1273
1274
1275 static int __init omap2_mcspi_init(void)
1276 {
1277 omap2_mcspi_wq = create_singlethread_workqueue(
1278 omap2_mcspi_driver.driver.name);
1279 if (omap2_mcspi_wq == NULL)
1280 return -1;
1281 return platform_driver_probe(&omap2_mcspi_driver, omap2_mcspi_probe);
1282 }
1283 subsys_initcall(omap2_mcspi_init);
1284
1285 static void __exit omap2_mcspi_exit(void)
1286 {
1287 platform_driver_unregister(&omap2_mcspi_driver);
1288
1289 destroy_workqueue(omap2_mcspi_wq);
1290 }
1291 module_exit(omap2_mcspi_exit);
1292
1293 MODULE_LICENSE("GPL");
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree