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SLUB: Fix memory leak by not reusing cpu_slab
[pv_ops_mirror.git] / drivers / spi / omap2_mcspi.c
blob3cdab131c4a9a55a0bea4221f5eb31aa0408b9aa
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 Yrjölä <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
36 #include <linux/spi/spi.h>
37
38 #include <asm/arch/dma.h>
39 #include <asm/arch/clock.h>
40
41
42 #define OMAP2_MCSPI_MAX_FREQ 48000000
43
44 #define OMAP2_MCSPI_REVISION 0x00
45 #define OMAP2_MCSPI_SYSCONFIG 0x10
46 #define OMAP2_MCSPI_SYSSTATUS 0x14
47 #define OMAP2_MCSPI_IRQSTATUS 0x18
48 #define OMAP2_MCSPI_IRQENABLE 0x1c
49 #define OMAP2_MCSPI_WAKEUPENABLE 0x20
50 #define OMAP2_MCSPI_SYST 0x24
51 #define OMAP2_MCSPI_MODULCTRL 0x28
52
53 /* per-channel banks, 0x14 bytes each, first is: */
54 #define OMAP2_MCSPI_CHCONF0 0x2c
55 #define OMAP2_MCSPI_CHSTAT0 0x30
56 #define OMAP2_MCSPI_CHCTRL0 0x34
57 #define OMAP2_MCSPI_TX0 0x38
58 #define OMAP2_MCSPI_RX0 0x3c
59
60 /* per-register bitmasks: */
61
62 #define OMAP2_MCSPI_SYSCONFIG_AUTOIDLE (1 << 0)
63 #define OMAP2_MCSPI_SYSCONFIG_SOFTRESET (1 << 1)
64
65 #define OMAP2_MCSPI_SYSSTATUS_RESETDONE (1 << 0)
66
67 #define OMAP2_MCSPI_MODULCTRL_SINGLE (1 << 0)
68 #define OMAP2_MCSPI_MODULCTRL_MS (1 << 2)
69 #define OMAP2_MCSPI_MODULCTRL_STEST (1 << 3)
70
71 #define OMAP2_MCSPI_CHCONF_PHA (1 << 0)
72 #define OMAP2_MCSPI_CHCONF_POL (1 << 1)
73 #define OMAP2_MCSPI_CHCONF_CLKD_MASK (0x0f << 2)
74 #define OMAP2_MCSPI_CHCONF_EPOL (1 << 6)
75 #define OMAP2_MCSPI_CHCONF_WL_MASK (0x1f << 7)
76 #define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY (0x01 << 12)
77 #define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY (0x02 << 12)
78 #define OMAP2_MCSPI_CHCONF_TRM_MASK (0x03 << 12)
79 #define OMAP2_MCSPI_CHCONF_DMAW (1 << 14)
80 #define OMAP2_MCSPI_CHCONF_DMAR (1 << 15)
81 #define OMAP2_MCSPI_CHCONF_DPE0 (1 << 16)
82 #define OMAP2_MCSPI_CHCONF_DPE1 (1 << 17)
83 #define OMAP2_MCSPI_CHCONF_IS (1 << 18)
84 #define OMAP2_MCSPI_CHCONF_TURBO (1 << 19)
85 #define OMAP2_MCSPI_CHCONF_FORCE (1 << 20)
86
87 #define OMAP2_MCSPI_CHSTAT_RXS (1 << 0)
88 #define OMAP2_MCSPI_CHSTAT_TXS (1 << 1)
89 #define OMAP2_MCSPI_CHSTAT_EOT (1 << 2)
90
91 #define OMAP2_MCSPI_CHCTRL_EN (1 << 0)
92
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 8
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 struct clk *ick;
119 struct clk *fck;
120 /* Virtual base address of the controller */
121 void __iomem *base;
122 /* SPI1 has 4 channels, while SPI2 has 2 */
123 struct omap2_mcspi_dma *dma_channels;
124 };
125
126 struct omap2_mcspi_cs {
127 void __iomem *base;
128 int word_len;
129 };
130
131 static struct workqueue_struct *omap2_mcspi_wq;
132
133 #define MOD_REG_BIT(val, mask, set) do { \
134 if (set) \
135 val |= mask; \
136 else \
137 val &= ~mask; \
138 } while (0)
139
140 static inline void mcspi_write_reg(struct spi_master *master,
141 int idx, u32 val)
142 {
143 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
144
145 __raw_writel(val, mcspi->base + idx);
146 }
147
148 static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
149 {
150 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
151
152 return __raw_readl(mcspi->base + idx);
153 }
154
155 static inline void mcspi_write_cs_reg(const struct spi_device *spi,
156 int idx, u32 val)
157 {
158 struct omap2_mcspi_cs *cs = spi->controller_state;
159
160 __raw_writel(val, cs->base + idx);
161 }
162
163 static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
164 {
165 struct omap2_mcspi_cs *cs = spi->controller_state;
166
167 return __raw_readl(cs->base + idx);
168 }
169
170 static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
171 int is_read, int enable)
172 {
173 u32 l, rw;
174
175 l = mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
176
177 if (is_read) /* 1 is read, 0 write */
178 rw = OMAP2_MCSPI_CHCONF_DMAR;
179 else
180 rw = OMAP2_MCSPI_CHCONF_DMAW;
181
182 MOD_REG_BIT(l, rw, enable);
183 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, l);
184 }
185
186 static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
187 {
188 u32 l;
189
190 l = enable ? OMAP2_MCSPI_CHCTRL_EN : 0;
191 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, l);
192 }
193
194 static void omap2_mcspi_force_cs(struct spi_device *spi, int cs_active)
195 {
196 u32 l;
197
198 l = mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
199 MOD_REG_BIT(l, OMAP2_MCSPI_CHCONF_FORCE, cs_active);
200 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, l);
201 }
202
203 static void omap2_mcspi_set_master_mode(struct spi_master *master)
204 {
205 u32 l;
206
207 /* setup when switching from (reset default) slave mode
208 * to single-channel master mode
209 */
210 l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
211 MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_STEST, 0);
212 MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_MS, 0);
213 MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_SINGLE, 1);
214 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
215 }
216
217 static unsigned
218 omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
219 {
220 struct omap2_mcspi *mcspi;
221 struct omap2_mcspi_cs *cs = spi->controller_state;
222 struct omap2_mcspi_dma *mcspi_dma;
223 unsigned int count, c;
224 unsigned long base, tx_reg, rx_reg;
225 int word_len, data_type, element_count;
226 u8 * rx;
227 const u8 * tx;
228
229 mcspi = spi_master_get_devdata(spi->master);
230 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
231
232 count = xfer->len;
233 c = count;
234 word_len = cs->word_len;
235
236 base = (unsigned long) io_v2p(cs->base);
237 tx_reg = base + OMAP2_MCSPI_TX0;
238 rx_reg = base + OMAP2_MCSPI_RX0;
239 rx = xfer->rx_buf;
240 tx = xfer->tx_buf;
241
242 if (word_len <= 8) {
243 data_type = OMAP_DMA_DATA_TYPE_S8;
244 element_count = count;
245 } else if (word_len <= 16) {
246 data_type = OMAP_DMA_DATA_TYPE_S16;
247 element_count = count >> 1;
248 } else /* word_len <= 32 */ {
249 data_type = OMAP_DMA_DATA_TYPE_S32;
250 element_count = count >> 2;
251 }
252
253 if (tx != NULL) {
254 omap_set_dma_transfer_params(mcspi_dma->dma_tx_channel,
255 data_type, element_count, 1,
256 OMAP_DMA_SYNC_ELEMENT,
257 mcspi_dma->dma_tx_sync_dev, 0);
258
259 omap_set_dma_dest_params(mcspi_dma->dma_tx_channel, 0,
260 OMAP_DMA_AMODE_CONSTANT,
261 tx_reg, 0, 0);
262
263 omap_set_dma_src_params(mcspi_dma->dma_tx_channel, 0,
264 OMAP_DMA_AMODE_POST_INC,
265 xfer->tx_dma, 0, 0);
266 }
267
268 if (rx != NULL) {
269 omap_set_dma_transfer_params(mcspi_dma->dma_rx_channel,
270 data_type, element_count, 1,
271 OMAP_DMA_SYNC_ELEMENT,
272 mcspi_dma->dma_rx_sync_dev, 1);
273
274 omap_set_dma_src_params(mcspi_dma->dma_rx_channel, 0,
275 OMAP_DMA_AMODE_CONSTANT,
276 rx_reg, 0, 0);
277
278 omap_set_dma_dest_params(mcspi_dma->dma_rx_channel, 0,
279 OMAP_DMA_AMODE_POST_INC,
280 xfer->rx_dma, 0, 0);
281 }
282
283 if (tx != NULL) {
284 omap_start_dma(mcspi_dma->dma_tx_channel);
285 omap2_mcspi_set_dma_req(spi, 0, 1);
286 }
287
288 if (rx != NULL) {
289 omap_start_dma(mcspi_dma->dma_rx_channel);
290 omap2_mcspi_set_dma_req(spi, 1, 1);
291 }
292
293 if (tx != NULL) {
294 wait_for_completion(&mcspi_dma->dma_tx_completion);
295 dma_unmap_single(NULL, xfer->tx_dma, count, DMA_TO_DEVICE);
296 }
297
298 if (rx != NULL) {
299 wait_for_completion(&mcspi_dma->dma_rx_completion);
300 dma_unmap_single(NULL, xfer->rx_dma, count, DMA_FROM_DEVICE);
301 }
302 return count;
303 }
304
305 static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
306 {
307 unsigned long timeout;
308
309 timeout = jiffies + msecs_to_jiffies(1000);
310 while (!(__raw_readl(reg) & bit)) {
311 if (time_after(jiffies, timeout))
312 return -1;
313 cpu_relax();
314 }
315 return 0;
316 }
317
318 static unsigned
319 omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
320 {
321 struct omap2_mcspi *mcspi;
322 struct omap2_mcspi_cs *cs = spi->controller_state;
323 unsigned int count, c;
324 u32 l;
325 void __iomem *base = cs->base;
326 void __iomem *tx_reg;
327 void __iomem *rx_reg;
328 void __iomem *chstat_reg;
329 int word_len;
330
331 mcspi = spi_master_get_devdata(spi->master);
332 count = xfer->len;
333 c = count;
334 word_len = cs->word_len;
335
336 l = mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
337 l &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
338
339 /* We store the pre-calculated register addresses on stack to speed
340 * up the transfer loop. */
341 tx_reg = base + OMAP2_MCSPI_TX0;
342 rx_reg = base + OMAP2_MCSPI_RX0;
343 chstat_reg = base + OMAP2_MCSPI_CHSTAT0;
344
345 if (word_len <= 8) {
346 u8 *rx;
347 const u8 *tx;
348
349 rx = xfer->rx_buf;
350 tx = xfer->tx_buf;
351
352 do {
353 if (tx != NULL) {
354 if (mcspi_wait_for_reg_bit(chstat_reg,
355 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
356 dev_err(&spi->dev, "TXS timed out\n");
357 goto out;
358 }
359 #ifdef VERBOSE
360 dev_dbg(&spi->dev, "write-%d %02x\n",
361 word_len, *tx);
362 #endif
363 __raw_writel(*tx++, tx_reg);
364 }
365 if (rx != NULL) {
366 if (mcspi_wait_for_reg_bit(chstat_reg,
367 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
368 dev_err(&spi->dev, "RXS timed out\n");
369 goto out;
370 }
371 /* prevent last RX_ONLY read from triggering
372 * more word i/o: switch to rx+tx
373 */
374 if (c == 0 && tx == NULL)
375 mcspi_write_cs_reg(spi,
376 OMAP2_MCSPI_CHCONF0, l);
377 *rx++ = __raw_readl(rx_reg);
378 #ifdef VERBOSE
379 dev_dbg(&spi->dev, "read-%d %02x\n",
380 word_len, *(rx - 1));
381 #endif
382 }
383 c -= 1;
384 } while (c);
385 } else if (word_len <= 16) {
386 u16 *rx;
387 const u16 *tx;
388
389 rx = xfer->rx_buf;
390 tx = xfer->tx_buf;
391 do {
392 if (tx != NULL) {
393 if (mcspi_wait_for_reg_bit(chstat_reg,
394 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
395 dev_err(&spi->dev, "TXS timed out\n");
396 goto out;
397 }
398 #ifdef VERBOSE
399 dev_dbg(&spi->dev, "write-%d %04x\n",
400 word_len, *tx);
401 #endif
402 __raw_writel(*tx++, tx_reg);
403 }
404 if (rx != NULL) {
405 if (mcspi_wait_for_reg_bit(chstat_reg,
406 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
407 dev_err(&spi->dev, "RXS timed out\n");
408 goto out;
409 }
410 /* prevent last RX_ONLY read from triggering
411 * more word i/o: switch to rx+tx
412 */
413 if (c == 0 && tx == NULL)
414 mcspi_write_cs_reg(spi,
415 OMAP2_MCSPI_CHCONF0, l);
416 *rx++ = __raw_readl(rx_reg);
417 #ifdef VERBOSE
418 dev_dbg(&spi->dev, "read-%d %04x\n",
419 word_len, *(rx - 1));
420 #endif
421 }
422 c -= 2;
423 } while (c);
424 } else if (word_len <= 32) {
425 u32 *rx;
426 const u32 *tx;
427
428 rx = xfer->rx_buf;
429 tx = xfer->tx_buf;
430 do {
431 if (tx != NULL) {
432 if (mcspi_wait_for_reg_bit(chstat_reg,
433 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
434 dev_err(&spi->dev, "TXS timed out\n");
435 goto out;
436 }
437 #ifdef VERBOSE
438 dev_dbg(&spi->dev, "write-%d %04x\n",
439 word_len, *tx);
440 #endif
441 __raw_writel(*tx++, tx_reg);
442 }
443 if (rx != NULL) {
444 if (mcspi_wait_for_reg_bit(chstat_reg,
445 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
446 dev_err(&spi->dev, "RXS timed out\n");
447 goto out;
448 }
449 /* prevent last RX_ONLY read from triggering
450 * more word i/o: switch to rx+tx
451 */
452 if (c == 0 && tx == NULL)
453 mcspi_write_cs_reg(spi,
454 OMAP2_MCSPI_CHCONF0, l);
455 *rx++ = __raw_readl(rx_reg);
456 #ifdef VERBOSE
457 dev_dbg(&spi->dev, "read-%d %04x\n",
458 word_len, *(rx - 1));
459 #endif
460 }
461 c -= 4;
462 } while (c);
463 }
464
465 /* for TX_ONLY mode, be sure all words have shifted out */
466 if (xfer->rx_buf == NULL) {
467 if (mcspi_wait_for_reg_bit(chstat_reg,
468 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
469 dev_err(&spi->dev, "TXS timed out\n");
470 } else if (mcspi_wait_for_reg_bit(chstat_reg,
471 OMAP2_MCSPI_CHSTAT_EOT) < 0)
472 dev_err(&spi->dev, "EOT timed out\n");
473 }
474 out:
475 return count - c;
476 }
477
478 /* called only when no transfer is active to this device */
479 static int omap2_mcspi_setup_transfer(struct spi_device *spi,
480 struct spi_transfer *t)
481 {
482 struct omap2_mcspi_cs *cs = spi->controller_state;
483 struct omap2_mcspi *mcspi;
484 u32 l = 0, div = 0;
485 u8 word_len = spi->bits_per_word;
486
487 mcspi = spi_master_get_devdata(spi->master);
488
489 if (t != NULL && t->bits_per_word)
490 word_len = t->bits_per_word;
491
492 cs->word_len = word_len;
493
494 if (spi->max_speed_hz) {
495 while (div <= 15 && (OMAP2_MCSPI_MAX_FREQ / (1 << div))
496 > spi->max_speed_hz)
497 div++;
498 } else
499 div = 15;
500
501 l = mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
502
503 /* standard 4-wire master mode: SCK, MOSI/out, MISO/in, nCS
504 * REVISIT: this controller could support SPI_3WIRE mode.
505 */
506 l &= ~(OMAP2_MCSPI_CHCONF_IS|OMAP2_MCSPI_CHCONF_DPE1);
507 l |= OMAP2_MCSPI_CHCONF_DPE0;
508
509 /* wordlength */
510 l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
511 l |= (word_len - 1) << 7;
512
513 /* set chipselect polarity; manage with FORCE */
514 if (!(spi->mode & SPI_CS_HIGH))
515 l |= OMAP2_MCSPI_CHCONF_EPOL; /* active-low; normal */
516 else
517 l &= ~OMAP2_MCSPI_CHCONF_EPOL;
518
519 /* set clock divisor */
520 l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
521 l |= div << 2;
522
523 /* set SPI mode 0..3 */
524 if (spi->mode & SPI_CPOL)
525 l |= OMAP2_MCSPI_CHCONF_POL;
526 else
527 l &= ~OMAP2_MCSPI_CHCONF_POL;
528 if (spi->mode & SPI_CPHA)
529 l |= OMAP2_MCSPI_CHCONF_PHA;
530 else
531 l &= ~OMAP2_MCSPI_CHCONF_PHA;
532
533 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, l);
534
535 dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
536 OMAP2_MCSPI_MAX_FREQ / (1 << div),
537 (spi->mode & SPI_CPHA) ? "trailing" : "leading",
538 (spi->mode & SPI_CPOL) ? "inverted" : "normal");
539
540 return 0;
541 }
542
543 static void omap2_mcspi_dma_rx_callback(int lch, u16 ch_status, void *data)
544 {
545 struct spi_device *spi = data;
546 struct omap2_mcspi *mcspi;
547 struct omap2_mcspi_dma *mcspi_dma;
548
549 mcspi = spi_master_get_devdata(spi->master);
550 mcspi_dma = &(mcspi->dma_channels[spi->chip_select]);
551
552 complete(&mcspi_dma->dma_rx_completion);
553
554 /* We must disable the DMA RX request */
555 omap2_mcspi_set_dma_req(spi, 1, 0);
556 }
557
558 static void omap2_mcspi_dma_tx_callback(int lch, u16 ch_status, void *data)
559 {
560 struct spi_device *spi = data;
561 struct omap2_mcspi *mcspi;
562 struct omap2_mcspi_dma *mcspi_dma;
563
564 mcspi = spi_master_get_devdata(spi->master);
565 mcspi_dma = &(mcspi->dma_channels[spi->chip_select]);
566
567 complete(&mcspi_dma->dma_tx_completion);
568
569 /* We must disable the DMA TX request */
570 omap2_mcspi_set_dma_req(spi, 0, 0);
571 }
572
573 static int omap2_mcspi_request_dma(struct spi_device *spi)
574 {
575 struct spi_master *master = spi->master;
576 struct omap2_mcspi *mcspi;
577 struct omap2_mcspi_dma *mcspi_dma;
578
579 mcspi = spi_master_get_devdata(master);
580 mcspi_dma = mcspi->dma_channels + spi->chip_select;
581
582 if (omap_request_dma(mcspi_dma->dma_rx_sync_dev, "McSPI RX",
583 omap2_mcspi_dma_rx_callback, spi,
584 &mcspi_dma->dma_rx_channel)) {
585 dev_err(&spi->dev, "no RX DMA channel for McSPI\n");
586 return -EAGAIN;
587 }
588
589 if (omap_request_dma(mcspi_dma->dma_tx_sync_dev, "McSPI TX",
590 omap2_mcspi_dma_tx_callback, spi,
591 &mcspi_dma->dma_tx_channel)) {
592 omap_free_dma(mcspi_dma->dma_rx_channel);
593 mcspi_dma->dma_rx_channel = -1;
594 dev_err(&spi->dev, "no TX DMA channel for McSPI\n");
595 return -EAGAIN;
596 }
597
598 init_completion(&mcspi_dma->dma_rx_completion);
599 init_completion(&mcspi_dma->dma_tx_completion);
600
601 return 0;
602 }
603
604 /* the spi->mode bits understood by this driver: */
605 #define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH)
606
607 static int omap2_mcspi_setup(struct spi_device *spi)
608 {
609 int ret;
610 struct omap2_mcspi *mcspi;
611 struct omap2_mcspi_dma *mcspi_dma;
612 struct omap2_mcspi_cs *cs = spi->controller_state;
613
614 if (spi->mode & ~MODEBITS) {
615 dev_dbg(&spi->dev, "setup: unsupported mode bits %x\n",
616 spi->mode & ~MODEBITS);
617 return -EINVAL;
618 }
619
620 if (spi->bits_per_word == 0)
621 spi->bits_per_word = 8;
622 else if (spi->bits_per_word < 4 || spi->bits_per_word > 32) {
623 dev_dbg(&spi->dev, "setup: unsupported %d bit words\n",
624 spi->bits_per_word);
625 return -EINVAL;
626 }
627
628 mcspi = spi_master_get_devdata(spi->master);
629 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
630
631 if (!cs) {
632 cs = kzalloc(sizeof *cs, GFP_KERNEL);
633 if (!cs)
634 return -ENOMEM;
635 cs->base = mcspi->base + spi->chip_select * 0x14;
636 spi->controller_state = cs;
637 }
638
639 if (mcspi_dma->dma_rx_channel == -1
640 || mcspi_dma->dma_tx_channel == -1) {
641 ret = omap2_mcspi_request_dma(spi);
642 if (ret < 0)
643 return ret;
644 }
645
646 clk_enable(mcspi->ick);
647 clk_enable(mcspi->fck);
648 ret = omap2_mcspi_setup_transfer(spi, NULL);
649 clk_disable(mcspi->fck);
650 clk_disable(mcspi->ick);
651
652 return ret;
653 }
654
655 static void omap2_mcspi_cleanup(struct spi_device *spi)
656 {
657 struct omap2_mcspi *mcspi;
658 struct omap2_mcspi_dma *mcspi_dma;
659
660 mcspi = spi_master_get_devdata(spi->master);
661 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
662
663 kfree(spi->controller_state);
664
665 if (mcspi_dma->dma_rx_channel != -1) {
666 omap_free_dma(mcspi_dma->dma_rx_channel);
667 mcspi_dma->dma_rx_channel = -1;
668 }
669 if (mcspi_dma->dma_tx_channel != -1) {
670 omap_free_dma(mcspi_dma->dma_tx_channel);
671 mcspi_dma->dma_tx_channel = -1;
672 }
673 }
674
675 static void omap2_mcspi_work(struct work_struct *work)
676 {
677 struct omap2_mcspi *mcspi;
678
679 mcspi = container_of(work, struct omap2_mcspi, work);
680 spin_lock_irq(&mcspi->lock);
681
682 clk_enable(mcspi->ick);
683 clk_enable(mcspi->fck);
684
685 /* We only enable one channel at a time -- the one whose message is
686 * at the head of the queue -- although this controller would gladly
687 * arbitrate among multiple channels. This corresponds to "single
688 * channel" master mode. As a side effect, we need to manage the
689 * chipselect with the FORCE bit ... CS != channel enable.
690 */
691 while (!list_empty(&mcspi->msg_queue)) {
692 struct spi_message *m;
693 struct spi_device *spi;
694 struct spi_transfer *t = NULL;
695 int cs_active = 0;
696 struct omap2_mcspi_cs *cs;
697 int par_override = 0;
698 int status = 0;
699 u32 chconf;
700
701 m = container_of(mcspi->msg_queue.next, struct spi_message,
702 queue);
703
704 list_del_init(&m->queue);
705 spin_unlock_irq(&mcspi->lock);
706
707 spi = m->spi;
708 cs = spi->controller_state;
709
710 omap2_mcspi_set_enable(spi, 1);
711 list_for_each_entry(t, &m->transfers, transfer_list) {
712 if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) {
713 status = -EINVAL;
714 break;
715 }
716 if (par_override || t->speed_hz || t->bits_per_word) {
717 par_override = 1;
718 status = omap2_mcspi_setup_transfer(spi, t);
719 if (status < 0)
720 break;
721 if (!t->speed_hz && !t->bits_per_word)
722 par_override = 0;
723 }
724
725 if (!cs_active) {
726 omap2_mcspi_force_cs(spi, 1);
727 cs_active = 1;
728 }
729
730 chconf = mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
731 chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
732 if (t->tx_buf == NULL)
733 chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
734 else if (t->rx_buf == NULL)
735 chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
736 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, chconf);
737
738 if (t->len) {
739 unsigned count;
740
741 /* RX_ONLY mode needs dummy data in TX reg */
742 if (t->tx_buf == NULL)
743 __raw_writel(0, cs->base
744 + OMAP2_MCSPI_TX0);
745
746 if (m->is_dma_mapped || t->len >= DMA_MIN_BYTES)
747 count = omap2_mcspi_txrx_dma(spi, t);
748 else
749 count = omap2_mcspi_txrx_pio(spi, t);
750 m->actual_length += count;
751
752 if (count != t->len) {
753 status = -EIO;
754 break;
755 }
756 }
757
758 if (t->delay_usecs)
759 udelay(t->delay_usecs);
760
761 /* ignore the "leave it on after last xfer" hint */
762 if (t->cs_change) {
763 omap2_mcspi_force_cs(spi, 0);
764 cs_active = 0;
765 }
766 }
767
768 /* Restore defaults if they were overriden */
769 if (par_override) {
770 par_override = 0;
771 status = omap2_mcspi_setup_transfer(spi, NULL);
772 }
773
774 if (cs_active)
775 omap2_mcspi_force_cs(spi, 0);
776
777 omap2_mcspi_set_enable(spi, 0);
778
779 m->status = status;
780 m->complete(m->context);
781
782 spin_lock_irq(&mcspi->lock);
783 }
784
785 clk_disable(mcspi->fck);
786 clk_disable(mcspi->ick);
787
788 spin_unlock_irq(&mcspi->lock);
789 }
790
791 static int omap2_mcspi_transfer(struct spi_device *spi, struct spi_message *m)
792 {
793 struct omap2_mcspi *mcspi;
794 unsigned long flags;
795 struct spi_transfer *t;
796
797 m->actual_length = 0;
798 m->status = 0;
799
800 /* reject invalid messages and transfers */
801 if (list_empty(&m->transfers) || !m->complete)
802 return -EINVAL;
803 list_for_each_entry(t, &m->transfers, transfer_list) {
804 const void *tx_buf = t->tx_buf;
805 void *rx_buf = t->rx_buf;
806 unsigned len = t->len;
807
808 if (t->speed_hz > OMAP2_MCSPI_MAX_FREQ
809 || (len && !(rx_buf || tx_buf))
810 || (t->bits_per_word &&
811 ( t->bits_per_word < 4
812 || t->bits_per_word > 32))) {
813 dev_dbg(&spi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
814 t->speed_hz,
815 len,
816 tx_buf ? "tx" : "",
817 rx_buf ? "rx" : "",
818 t->bits_per_word);
819 return -EINVAL;
820 }
821 if (t->speed_hz && t->speed_hz < OMAP2_MCSPI_MAX_FREQ/(1<<16)) {
822 dev_dbg(&spi->dev, "%d Hz max exceeds %d\n",
823 t->speed_hz,
824 OMAP2_MCSPI_MAX_FREQ/(1<<16));
825 return -EINVAL;
826 }
827
828 if (m->is_dma_mapped || len < DMA_MIN_BYTES)
829 continue;
830
831 /* Do DMA mapping "early" for better error reporting and
832 * dcache use. Note that if dma_unmap_single() ever starts
833 * to do real work on ARM, we'd need to clean up mappings
834 * for previous transfers on *ALL* exits of this loop...
835 */
836 if (tx_buf != NULL) {
837 t->tx_dma = dma_map_single(&spi->dev, (void *) tx_buf,
838 len, DMA_TO_DEVICE);
839 if (dma_mapping_error(t->tx_dma)) {
840 dev_dbg(&spi->dev, "dma %cX %d bytes error\n",
841 'T', len);
842 return -EINVAL;
843 }
844 }
845 if (rx_buf != NULL) {
846 t->rx_dma = dma_map_single(&spi->dev, rx_buf, t->len,
847 DMA_FROM_DEVICE);
848 if (dma_mapping_error(t->rx_dma)) {
849 dev_dbg(&spi->dev, "dma %cX %d bytes error\n",
850 'R', len);
851 if (tx_buf != NULL)
852 dma_unmap_single(NULL, t->tx_dma,
853 len, DMA_TO_DEVICE);
854 return -EINVAL;
855 }
856 }
857 }
858
859 mcspi = spi_master_get_devdata(spi->master);
860
861 spin_lock_irqsave(&mcspi->lock, flags);
862 list_add_tail(&m->queue, &mcspi->msg_queue);
863 queue_work(omap2_mcspi_wq, &mcspi->work);
864 spin_unlock_irqrestore(&mcspi->lock, flags);
865
866 return 0;
867 }
868
869 static int __init omap2_mcspi_reset(struct omap2_mcspi *mcspi)
870 {
871 struct spi_master *master = mcspi->master;
872 u32 tmp;
873
874 clk_enable(mcspi->ick);
875 clk_enable(mcspi->fck);
876
877 mcspi_write_reg(master, OMAP2_MCSPI_SYSCONFIG,
878 OMAP2_MCSPI_SYSCONFIG_SOFTRESET);
879 do {
880 tmp = mcspi_read_reg(master, OMAP2_MCSPI_SYSSTATUS);
881 } while (!(tmp & OMAP2_MCSPI_SYSSTATUS_RESETDONE));
882
883 mcspi_write_reg(master, OMAP2_MCSPI_SYSCONFIG,
884 /* (3 << 8) | (2 << 3) | */
885 OMAP2_MCSPI_SYSCONFIG_AUTOIDLE);
886
887 omap2_mcspi_set_master_mode(master);
888
889 clk_disable(mcspi->fck);
890 clk_disable(mcspi->ick);
891 return 0;
892 }
893
894 static u8 __initdata spi1_rxdma_id [] = {
895 OMAP24XX_DMA_SPI1_RX0,
896 OMAP24XX_DMA_SPI1_RX1,
897 OMAP24XX_DMA_SPI1_RX2,
898 OMAP24XX_DMA_SPI1_RX3,
899 };
900
901 static u8 __initdata spi1_txdma_id [] = {
902 OMAP24XX_DMA_SPI1_TX0,
903 OMAP24XX_DMA_SPI1_TX1,
904 OMAP24XX_DMA_SPI1_TX2,
905 OMAP24XX_DMA_SPI1_TX3,
906 };
907
908 static u8 __initdata spi2_rxdma_id[] = {
909 OMAP24XX_DMA_SPI2_RX0,
910 OMAP24XX_DMA_SPI2_RX1,
911 };
912
913 static u8 __initdata spi2_txdma_id[] = {
914 OMAP24XX_DMA_SPI2_TX0,
915 OMAP24XX_DMA_SPI2_TX1,
916 };
917
918 static int __init omap2_mcspi_probe(struct platform_device *pdev)
919 {
920 struct spi_master *master;
921 struct omap2_mcspi *mcspi;
922 struct resource *r;
923 int status = 0, i;
924 const u8 *rxdma_id, *txdma_id;
925 unsigned num_chipselect;
926
927 switch (pdev->id) {
928 case 1:
929 rxdma_id = spi1_rxdma_id;
930 txdma_id = spi1_txdma_id;
931 num_chipselect = 4;
932 break;
933 case 2:
934 rxdma_id = spi2_rxdma_id;
935 txdma_id = spi2_txdma_id;
936 num_chipselect = 2;
937 break;
938 /* REVISIT omap2430 has a third McSPI ... */
939 default:
940 return -EINVAL;
941 }
942
943 master = spi_alloc_master(&pdev->dev, sizeof *mcspi);
944 if (master == NULL) {
945 dev_dbg(&pdev->dev, "master allocation failed\n");
946 return -ENOMEM;
947 }
948
949 if (pdev->id != -1)
950 master->bus_num = pdev->id;
951
952 master->setup = omap2_mcspi_setup;
953 master->transfer = omap2_mcspi_transfer;
954 master->cleanup = omap2_mcspi_cleanup;
955 master->num_chipselect = num_chipselect;
956
957 dev_set_drvdata(&pdev->dev, master);
958
959 mcspi = spi_master_get_devdata(master);
960 mcspi->master = master;
961
962 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
963 if (r == NULL) {
964 status = -ENODEV;
965 goto err1;
966 }
967 if (!request_mem_region(r->start, (r->end - r->start) + 1,
968 pdev->dev.bus_id)) {
969 status = -EBUSY;
970 goto err1;
971 }
972
973 mcspi->base = (void __iomem *) io_p2v(r->start);
974
975 INIT_WORK(&mcspi->work, omap2_mcspi_work);
976
977 spin_lock_init(&mcspi->lock);
978 INIT_LIST_HEAD(&mcspi->msg_queue);
979
980 mcspi->ick = clk_get(&pdev->dev, "mcspi_ick");
981 if (IS_ERR(mcspi->ick)) {
982 dev_dbg(&pdev->dev, "can't get mcspi_ick\n");
983 status = PTR_ERR(mcspi->ick);
984 goto err1a;
985 }
986 mcspi->fck = clk_get(&pdev->dev, "mcspi_fck");
987 if (IS_ERR(mcspi->fck)) {
988 dev_dbg(&pdev->dev, "can't get mcspi_fck\n");
989 status = PTR_ERR(mcspi->fck);
990 goto err2;
991 }
992
993 mcspi->dma_channels = kcalloc(master->num_chipselect,
994 sizeof(struct omap2_mcspi_dma),
995 GFP_KERNEL);
996
997 if (mcspi->dma_channels == NULL)
998 goto err3;
999
1000 for (i = 0; i < num_chipselect; i++) {
1001 mcspi->dma_channels[i].dma_rx_channel = -1;
1002 mcspi->dma_channels[i].dma_rx_sync_dev = rxdma_id[i];
1003 mcspi->dma_channels[i].dma_tx_channel = -1;
1004 mcspi->dma_channels[i].dma_tx_sync_dev = txdma_id[i];
1005 }
1006
1007 if (omap2_mcspi_reset(mcspi) < 0)
1008 goto err4;
1009
1010 status = spi_register_master(master);
1011 if (status < 0)
1012 goto err4;
1013
1014 return status;
1015
1016 err4:
1017 kfree(mcspi->dma_channels);
1018 err3:
1019 clk_put(mcspi->fck);
1020 err2:
1021 clk_put(mcspi->ick);
1022 err1a:
1023 release_mem_region(r->start, (r->end - r->start) + 1);
1024 err1:
1025 spi_master_put(master);
1026 return status;
1027 }
1028
1029 static int __exit omap2_mcspi_remove(struct platform_device *pdev)
1030 {
1031 struct spi_master *master;
1032 struct omap2_mcspi *mcspi;
1033 struct omap2_mcspi_dma *dma_channels;
1034 struct resource *r;
1035
1036 master = dev_get_drvdata(&pdev->dev);
1037 mcspi = spi_master_get_devdata(master);
1038 dma_channels = mcspi->dma_channels;
1039
1040 clk_put(mcspi->fck);
1041 clk_put(mcspi->ick);
1042
1043 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1044 release_mem_region(r->start, (r->end - r->start) + 1);
1045
1046 spi_unregister_master(master);
1047 kfree(dma_channels);
1048
1049 return 0;
1050 }
1051
1052 static struct platform_driver omap2_mcspi_driver = {
1053 .driver = {
1054 .name = "omap2_mcspi",
1055 .owner = THIS_MODULE,
1056 },
1057 .remove = __exit_p(omap2_mcspi_remove),
1058 };
1059
1060
1061 static int __init omap2_mcspi_init(void)
1062 {
1063 omap2_mcspi_wq = create_singlethread_workqueue(
1064 omap2_mcspi_driver.driver.name);
1065 if (omap2_mcspi_wq == NULL)
1066 return -1;
1067 return platform_driver_probe(&omap2_mcspi_driver, omap2_mcspi_probe);
1068 }
1069 subsys_initcall(omap2_mcspi_init);
1070
1071 static void __exit omap2_mcspi_exit(void)
1072 {
1073 platform_driver_unregister(&omap2_mcspi_driver);
1074
1075 destroy_workqueue(omap2_mcspi_wq);
1076 }
1077 module_exit(omap2_mcspi_exit);
1078
1079 MODULE_LICENSE("GPL");
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