xref: /openbmc/linux/drivers/spi/spi-omap2-mcspi.c (revision 05bcf503)
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/dmaengine.h>
32 #include <linux/omap-dma.h>
33 #include <linux/platform_device.h>
34 #include <linux/err.h>
35 #include <linux/clk.h>
36 #include <linux/io.h>
37 #include <linux/slab.h>
38 #include <linux/pm_runtime.h>
39 #include <linux/of.h>
40 #include <linux/of_device.h>
41 #include <linux/pinctrl/consumer.h>
42 #include <linux/err.h>
43 
44 #include <linux/spi/spi.h>
45 
46 #include <linux/platform_data/spi-omap2-mcspi.h>
47 
48 #define OMAP2_MCSPI_MAX_FREQ		48000000
49 #define SPI_AUTOSUSPEND_TIMEOUT		2000
50 
51 #define OMAP2_MCSPI_REVISION		0x00
52 #define OMAP2_MCSPI_SYSSTATUS		0x14
53 #define OMAP2_MCSPI_IRQSTATUS		0x18
54 #define OMAP2_MCSPI_IRQENABLE		0x1c
55 #define OMAP2_MCSPI_WAKEUPENABLE	0x20
56 #define OMAP2_MCSPI_SYST		0x24
57 #define OMAP2_MCSPI_MODULCTRL		0x28
58 
59 /* per-channel banks, 0x14 bytes each, first is: */
60 #define OMAP2_MCSPI_CHCONF0		0x2c
61 #define OMAP2_MCSPI_CHSTAT0		0x30
62 #define OMAP2_MCSPI_CHCTRL0		0x34
63 #define OMAP2_MCSPI_TX0			0x38
64 #define OMAP2_MCSPI_RX0			0x3c
65 
66 /* per-register bitmasks: */
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 
88 #define OMAP2_MCSPI_CHSTAT_RXS		BIT(0)
89 #define OMAP2_MCSPI_CHSTAT_TXS		BIT(1)
90 #define OMAP2_MCSPI_CHSTAT_EOT		BIT(2)
91 
92 #define OMAP2_MCSPI_CHCTRL_EN		BIT(0)
93 
94 #define OMAP2_MCSPI_WAKEUPENABLE_WKEN	BIT(0)
95 
96 /* We have 2 DMA channels per CS, one for RX and one for TX */
97 struct omap2_mcspi_dma {
98 	struct dma_chan *dma_tx;
99 	struct dma_chan *dma_rx;
100 
101 	int dma_tx_sync_dev;
102 	int dma_rx_sync_dev;
103 
104 	struct completion dma_tx_completion;
105 	struct completion dma_rx_completion;
106 };
107 
108 /* use PIO for small transfers, avoiding DMA setup/teardown overhead and
109  * cache operations; better heuristics consider wordsize and bitrate.
110  */
111 #define DMA_MIN_BYTES			160
112 
113 
114 /*
115  * Used for context save and restore, structure members to be updated whenever
116  * corresponding registers are modified.
117  */
118 struct omap2_mcspi_regs {
119 	u32 modulctrl;
120 	u32 wakeupenable;
121 	struct list_head cs;
122 };
123 
124 struct omap2_mcspi {
125 	struct spi_master	*master;
126 	/* Virtual base address of the controller */
127 	void __iomem		*base;
128 	unsigned long		phys;
129 	/* SPI1 has 4 channels, while SPI2 has 2 */
130 	struct omap2_mcspi_dma	*dma_channels;
131 	struct device		*dev;
132 	struct omap2_mcspi_regs ctx;
133 };
134 
135 struct omap2_mcspi_cs {
136 	void __iomem		*base;
137 	unsigned long		phys;
138 	int			word_len;
139 	struct list_head	node;
140 	/* Context save and restore shadow register */
141 	u32			chconf0;
142 };
143 
144 static inline void mcspi_write_reg(struct spi_master *master,
145 		int idx, u32 val)
146 {
147 	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
148 
149 	__raw_writel(val, mcspi->base + idx);
150 }
151 
152 static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
153 {
154 	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
155 
156 	return __raw_readl(mcspi->base + idx);
157 }
158 
159 static inline void mcspi_write_cs_reg(const struct spi_device *spi,
160 		int idx, u32 val)
161 {
162 	struct omap2_mcspi_cs	*cs = spi->controller_state;
163 
164 	__raw_writel(val, cs->base +  idx);
165 }
166 
167 static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
168 {
169 	struct omap2_mcspi_cs	*cs = spi->controller_state;
170 
171 	return __raw_readl(cs->base + idx);
172 }
173 
174 static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
175 {
176 	struct omap2_mcspi_cs *cs = spi->controller_state;
177 
178 	return cs->chconf0;
179 }
180 
181 static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
182 {
183 	struct omap2_mcspi_cs *cs = spi->controller_state;
184 
185 	cs->chconf0 = val;
186 	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
187 	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
188 }
189 
190 static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
191 		int is_read, int enable)
192 {
193 	u32 l, rw;
194 
195 	l = mcspi_cached_chconf0(spi);
196 
197 	if (is_read) /* 1 is read, 0 write */
198 		rw = OMAP2_MCSPI_CHCONF_DMAR;
199 	else
200 		rw = OMAP2_MCSPI_CHCONF_DMAW;
201 
202 	if (enable)
203 		l |= rw;
204 	else
205 		l &= ~rw;
206 
207 	mcspi_write_chconf0(spi, l);
208 }
209 
210 static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
211 {
212 	u32 l;
213 
214 	l = enable ? OMAP2_MCSPI_CHCTRL_EN : 0;
215 	mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, l);
216 	/* Flash post-writes */
217 	mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
218 }
219 
220 static void omap2_mcspi_force_cs(struct spi_device *spi, int cs_active)
221 {
222 	u32 l;
223 
224 	l = mcspi_cached_chconf0(spi);
225 	if (cs_active)
226 		l |= OMAP2_MCSPI_CHCONF_FORCE;
227 	else
228 		l &= ~OMAP2_MCSPI_CHCONF_FORCE;
229 
230 	mcspi_write_chconf0(spi, l);
231 }
232 
233 static void omap2_mcspi_set_master_mode(struct spi_master *master)
234 {
235 	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
236 	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
237 	u32 l;
238 
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 	l &= ~(OMAP2_MCSPI_MODULCTRL_STEST | OMAP2_MCSPI_MODULCTRL_MS);
245 	l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
246 	mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
247 
248 	ctx->modulctrl = l;
249 }
250 
251 static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
252 {
253 	struct spi_master	*spi_cntrl = mcspi->master;
254 	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
255 	struct omap2_mcspi_cs	*cs;
256 
257 	/* McSPI: context restore */
258 	mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
259 	mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
260 
261 	list_for_each_entry(cs, &ctx->cs, node)
262 		__raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
263 }
264 
265 static int omap2_prepare_transfer(struct spi_master *master)
266 {
267 	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
268 
269 	pm_runtime_get_sync(mcspi->dev);
270 	return 0;
271 }
272 
273 static int omap2_unprepare_transfer(struct spi_master *master)
274 {
275 	struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
276 
277 	pm_runtime_mark_last_busy(mcspi->dev);
278 	pm_runtime_put_autosuspend(mcspi->dev);
279 	return 0;
280 }
281 
282 static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
283 {
284 	unsigned long timeout;
285 
286 	timeout = jiffies + msecs_to_jiffies(1000);
287 	while (!(__raw_readl(reg) & bit)) {
288 		if (time_after(jiffies, timeout))
289 			return -1;
290 		cpu_relax();
291 	}
292 	return 0;
293 }
294 
295 static void omap2_mcspi_rx_callback(void *data)
296 {
297 	struct spi_device *spi = data;
298 	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
299 	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
300 
301 	complete(&mcspi_dma->dma_rx_completion);
302 
303 	/* We must disable the DMA RX request */
304 	omap2_mcspi_set_dma_req(spi, 1, 0);
305 }
306 
307 static void omap2_mcspi_tx_callback(void *data)
308 {
309 	struct spi_device *spi = data;
310 	struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
311 	struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
312 
313 	complete(&mcspi_dma->dma_tx_completion);
314 
315 	/* We must disable the DMA TX request */
316 	omap2_mcspi_set_dma_req(spi, 0, 0);
317 }
318 
319 static void omap2_mcspi_tx_dma(struct spi_device *spi,
320 				struct spi_transfer *xfer,
321 				struct dma_slave_config cfg)
322 {
323 	struct omap2_mcspi	*mcspi;
324 	struct omap2_mcspi_dma  *mcspi_dma;
325 	unsigned int		count;
326 	u8			* rx;
327 	const u8		* tx;
328 	void __iomem		*chstat_reg;
329 	struct omap2_mcspi_cs	*cs = spi->controller_state;
330 
331 	mcspi = spi_master_get_devdata(spi->master);
332 	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
333 	count = xfer->len;
334 
335 	rx = xfer->rx_buf;
336 	tx = xfer->tx_buf;
337 	chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
338 
339 	if (mcspi_dma->dma_tx) {
340 		struct dma_async_tx_descriptor *tx;
341 		struct scatterlist sg;
342 
343 		dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
344 
345 		sg_init_table(&sg, 1);
346 		sg_dma_address(&sg) = xfer->tx_dma;
347 		sg_dma_len(&sg) = xfer->len;
348 
349 		tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, &sg, 1,
350 		DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
351 		if (tx) {
352 			tx->callback = omap2_mcspi_tx_callback;
353 			tx->callback_param = spi;
354 			dmaengine_submit(tx);
355 		} else {
356 			/* FIXME: fall back to PIO? */
357 		}
358 	}
359 	dma_async_issue_pending(mcspi_dma->dma_tx);
360 	omap2_mcspi_set_dma_req(spi, 0, 1);
361 
362 	wait_for_completion(&mcspi_dma->dma_tx_completion);
363 	dma_unmap_single(mcspi->dev, xfer->tx_dma, count,
364 			 DMA_TO_DEVICE);
365 
366 	/* for TX_ONLY mode, be sure all words have shifted out */
367 	if (rx == NULL) {
368 		if (mcspi_wait_for_reg_bit(chstat_reg,
369 					OMAP2_MCSPI_CHSTAT_TXS) < 0)
370 			dev_err(&spi->dev, "TXS timed out\n");
371 		else if (mcspi_wait_for_reg_bit(chstat_reg,
372 					OMAP2_MCSPI_CHSTAT_EOT) < 0)
373 			dev_err(&spi->dev, "EOT timed out\n");
374 	}
375 }
376 
377 static unsigned
378 omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
379 				struct dma_slave_config cfg,
380 				unsigned es)
381 {
382 	struct omap2_mcspi	*mcspi;
383 	struct omap2_mcspi_dma  *mcspi_dma;
384 	unsigned int		count;
385 	u32			l;
386 	int			elements = 0;
387 	int			word_len, element_count;
388 	struct omap2_mcspi_cs	*cs = spi->controller_state;
389 	mcspi = spi_master_get_devdata(spi->master);
390 	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
391 	count = xfer->len;
392 	word_len = cs->word_len;
393 	l = mcspi_cached_chconf0(spi);
394 
395 	if (word_len <= 8)
396 		element_count = count;
397 	else if (word_len <= 16)
398 		element_count = count >> 1;
399 	else /* word_len <= 32 */
400 		element_count = count >> 2;
401 
402 	if (mcspi_dma->dma_rx) {
403 		struct dma_async_tx_descriptor *tx;
404 		struct scatterlist sg;
405 		size_t len = xfer->len - es;
406 
407 		dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
408 
409 		if (l & OMAP2_MCSPI_CHCONF_TURBO)
410 			len -= es;
411 
412 		sg_init_table(&sg, 1);
413 		sg_dma_address(&sg) = xfer->rx_dma;
414 		sg_dma_len(&sg) = len;
415 
416 		tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, &sg, 1,
417 				DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT |
418 				DMA_CTRL_ACK);
419 		if (tx) {
420 			tx->callback = omap2_mcspi_rx_callback;
421 			tx->callback_param = spi;
422 			dmaengine_submit(tx);
423 		} else {
424 				/* FIXME: fall back to PIO? */
425 		}
426 	}
427 
428 	dma_async_issue_pending(mcspi_dma->dma_rx);
429 	omap2_mcspi_set_dma_req(spi, 1, 1);
430 
431 	wait_for_completion(&mcspi_dma->dma_rx_completion);
432 	dma_unmap_single(mcspi->dev, xfer->rx_dma, count,
433 			 DMA_FROM_DEVICE);
434 	omap2_mcspi_set_enable(spi, 0);
435 
436 	elements = element_count - 1;
437 
438 	if (l & OMAP2_MCSPI_CHCONF_TURBO) {
439 		elements--;
440 
441 		if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
442 				   & OMAP2_MCSPI_CHSTAT_RXS)) {
443 			u32 w;
444 
445 			w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
446 			if (word_len <= 8)
447 				((u8 *)xfer->rx_buf)[elements++] = w;
448 			else if (word_len <= 16)
449 				((u16 *)xfer->rx_buf)[elements++] = w;
450 			else /* word_len <= 32 */
451 				((u32 *)xfer->rx_buf)[elements++] = w;
452 		} else {
453 			dev_err(&spi->dev, "DMA RX penultimate word empty");
454 			count -= (word_len <= 8)  ? 2 :
455 				(word_len <= 16) ? 4 :
456 				/* word_len <= 32 */ 8;
457 			omap2_mcspi_set_enable(spi, 1);
458 			return count;
459 		}
460 	}
461 	if (likely(mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHSTAT0)
462 				& OMAP2_MCSPI_CHSTAT_RXS)) {
463 		u32 w;
464 
465 		w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
466 		if (word_len <= 8)
467 			((u8 *)xfer->rx_buf)[elements] = w;
468 		else if (word_len <= 16)
469 			((u16 *)xfer->rx_buf)[elements] = w;
470 		else /* word_len <= 32 */
471 			((u32 *)xfer->rx_buf)[elements] = w;
472 	} else {
473 		dev_err(&spi->dev, "DMA RX last word empty");
474 		count -= (word_len <= 8)  ? 1 :
475 			 (word_len <= 16) ? 2 :
476 		       /* word_len <= 32 */ 4;
477 	}
478 	omap2_mcspi_set_enable(spi, 1);
479 	return count;
480 }
481 
482 static unsigned
483 omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
484 {
485 	struct omap2_mcspi	*mcspi;
486 	struct omap2_mcspi_cs	*cs = spi->controller_state;
487 	struct omap2_mcspi_dma  *mcspi_dma;
488 	unsigned int		count;
489 	u32			l;
490 	u8			*rx;
491 	const u8		*tx;
492 	struct dma_slave_config	cfg;
493 	enum dma_slave_buswidth width;
494 	unsigned es;
495 
496 	mcspi = spi_master_get_devdata(spi->master);
497 	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
498 	l = mcspi_cached_chconf0(spi);
499 
500 
501 	if (cs->word_len <= 8) {
502 		width = DMA_SLAVE_BUSWIDTH_1_BYTE;
503 		es = 1;
504 	} else if (cs->word_len <= 16) {
505 		width = DMA_SLAVE_BUSWIDTH_2_BYTES;
506 		es = 2;
507 	} else {
508 		width = DMA_SLAVE_BUSWIDTH_4_BYTES;
509 		es = 4;
510 	}
511 
512 	memset(&cfg, 0, sizeof(cfg));
513 	cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
514 	cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
515 	cfg.src_addr_width = width;
516 	cfg.dst_addr_width = width;
517 	cfg.src_maxburst = 1;
518 	cfg.dst_maxburst = 1;
519 
520 	rx = xfer->rx_buf;
521 	tx = xfer->tx_buf;
522 
523 	count = xfer->len;
524 
525 	if (tx != NULL)
526 		omap2_mcspi_tx_dma(spi, xfer, cfg);
527 
528 	if (rx != NULL)
529 		return omap2_mcspi_rx_dma(spi, xfer, cfg, es);
530 
531 	return count;
532 }
533 
534 static unsigned
535 omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
536 {
537 	struct omap2_mcspi	*mcspi;
538 	struct omap2_mcspi_cs	*cs = spi->controller_state;
539 	unsigned int		count, c;
540 	u32			l;
541 	void __iomem		*base = cs->base;
542 	void __iomem		*tx_reg;
543 	void __iomem		*rx_reg;
544 	void __iomem		*chstat_reg;
545 	int			word_len;
546 
547 	mcspi = spi_master_get_devdata(spi->master);
548 	count = xfer->len;
549 	c = count;
550 	word_len = cs->word_len;
551 
552 	l = mcspi_cached_chconf0(spi);
553 
554 	/* We store the pre-calculated register addresses on stack to speed
555 	 * up the transfer loop. */
556 	tx_reg		= base + OMAP2_MCSPI_TX0;
557 	rx_reg		= base + OMAP2_MCSPI_RX0;
558 	chstat_reg	= base + OMAP2_MCSPI_CHSTAT0;
559 
560 	if (c < (word_len>>3))
561 		return 0;
562 
563 	if (word_len <= 8) {
564 		u8		*rx;
565 		const u8	*tx;
566 
567 		rx = xfer->rx_buf;
568 		tx = xfer->tx_buf;
569 
570 		do {
571 			c -= 1;
572 			if (tx != NULL) {
573 				if (mcspi_wait_for_reg_bit(chstat_reg,
574 						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
575 					dev_err(&spi->dev, "TXS timed out\n");
576 					goto out;
577 				}
578 				dev_vdbg(&spi->dev, "write-%d %02x\n",
579 						word_len, *tx);
580 				__raw_writel(*tx++, tx_reg);
581 			}
582 			if (rx != NULL) {
583 				if (mcspi_wait_for_reg_bit(chstat_reg,
584 						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
585 					dev_err(&spi->dev, "RXS timed out\n");
586 					goto out;
587 				}
588 
589 				if (c == 1 && tx == NULL &&
590 				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
591 					omap2_mcspi_set_enable(spi, 0);
592 					*rx++ = __raw_readl(rx_reg);
593 					dev_vdbg(&spi->dev, "read-%d %02x\n",
594 						    word_len, *(rx - 1));
595 					if (mcspi_wait_for_reg_bit(chstat_reg,
596 						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
597 						dev_err(&spi->dev,
598 							"RXS timed out\n");
599 						goto out;
600 					}
601 					c = 0;
602 				} else if (c == 0 && tx == NULL) {
603 					omap2_mcspi_set_enable(spi, 0);
604 				}
605 
606 				*rx++ = __raw_readl(rx_reg);
607 				dev_vdbg(&spi->dev, "read-%d %02x\n",
608 						word_len, *(rx - 1));
609 			}
610 		} while (c);
611 	} else if (word_len <= 16) {
612 		u16		*rx;
613 		const u16	*tx;
614 
615 		rx = xfer->rx_buf;
616 		tx = xfer->tx_buf;
617 		do {
618 			c -= 2;
619 			if (tx != NULL) {
620 				if (mcspi_wait_for_reg_bit(chstat_reg,
621 						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
622 					dev_err(&spi->dev, "TXS timed out\n");
623 					goto out;
624 				}
625 				dev_vdbg(&spi->dev, "write-%d %04x\n",
626 						word_len, *tx);
627 				__raw_writel(*tx++, tx_reg);
628 			}
629 			if (rx != NULL) {
630 				if (mcspi_wait_for_reg_bit(chstat_reg,
631 						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
632 					dev_err(&spi->dev, "RXS timed out\n");
633 					goto out;
634 				}
635 
636 				if (c == 2 && tx == NULL &&
637 				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
638 					omap2_mcspi_set_enable(spi, 0);
639 					*rx++ = __raw_readl(rx_reg);
640 					dev_vdbg(&spi->dev, "read-%d %04x\n",
641 						    word_len, *(rx - 1));
642 					if (mcspi_wait_for_reg_bit(chstat_reg,
643 						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
644 						dev_err(&spi->dev,
645 							"RXS timed out\n");
646 						goto out;
647 					}
648 					c = 0;
649 				} else if (c == 0 && tx == NULL) {
650 					omap2_mcspi_set_enable(spi, 0);
651 				}
652 
653 				*rx++ = __raw_readl(rx_reg);
654 				dev_vdbg(&spi->dev, "read-%d %04x\n",
655 						word_len, *(rx - 1));
656 			}
657 		} while (c >= 2);
658 	} else if (word_len <= 32) {
659 		u32		*rx;
660 		const u32	*tx;
661 
662 		rx = xfer->rx_buf;
663 		tx = xfer->tx_buf;
664 		do {
665 			c -= 4;
666 			if (tx != NULL) {
667 				if (mcspi_wait_for_reg_bit(chstat_reg,
668 						OMAP2_MCSPI_CHSTAT_TXS) < 0) {
669 					dev_err(&spi->dev, "TXS timed out\n");
670 					goto out;
671 				}
672 				dev_vdbg(&spi->dev, "write-%d %08x\n",
673 						word_len, *tx);
674 				__raw_writel(*tx++, tx_reg);
675 			}
676 			if (rx != NULL) {
677 				if (mcspi_wait_for_reg_bit(chstat_reg,
678 						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
679 					dev_err(&spi->dev, "RXS timed out\n");
680 					goto out;
681 				}
682 
683 				if (c == 4 && tx == NULL &&
684 				    (l & OMAP2_MCSPI_CHCONF_TURBO)) {
685 					omap2_mcspi_set_enable(spi, 0);
686 					*rx++ = __raw_readl(rx_reg);
687 					dev_vdbg(&spi->dev, "read-%d %08x\n",
688 						    word_len, *(rx - 1));
689 					if (mcspi_wait_for_reg_bit(chstat_reg,
690 						OMAP2_MCSPI_CHSTAT_RXS) < 0) {
691 						dev_err(&spi->dev,
692 							"RXS timed out\n");
693 						goto out;
694 					}
695 					c = 0;
696 				} else if (c == 0 && tx == NULL) {
697 					omap2_mcspi_set_enable(spi, 0);
698 				}
699 
700 				*rx++ = __raw_readl(rx_reg);
701 				dev_vdbg(&spi->dev, "read-%d %08x\n",
702 						word_len, *(rx - 1));
703 			}
704 		} while (c >= 4);
705 	}
706 
707 	/* for TX_ONLY mode, be sure all words have shifted out */
708 	if (xfer->rx_buf == NULL) {
709 		if (mcspi_wait_for_reg_bit(chstat_reg,
710 				OMAP2_MCSPI_CHSTAT_TXS) < 0) {
711 			dev_err(&spi->dev, "TXS timed out\n");
712 		} else if (mcspi_wait_for_reg_bit(chstat_reg,
713 				OMAP2_MCSPI_CHSTAT_EOT) < 0)
714 			dev_err(&spi->dev, "EOT timed out\n");
715 
716 		/* disable chan to purge rx datas received in TX_ONLY transfer,
717 		 * otherwise these rx datas will affect the direct following
718 		 * RX_ONLY transfer.
719 		 */
720 		omap2_mcspi_set_enable(spi, 0);
721 	}
722 out:
723 	omap2_mcspi_set_enable(spi, 1);
724 	return count - c;
725 }
726 
727 static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
728 {
729 	u32 div;
730 
731 	for (div = 0; div < 15; div++)
732 		if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
733 			return div;
734 
735 	return 15;
736 }
737 
738 /* called only when no transfer is active to this device */
739 static int omap2_mcspi_setup_transfer(struct spi_device *spi,
740 		struct spi_transfer *t)
741 {
742 	struct omap2_mcspi_cs *cs = spi->controller_state;
743 	struct omap2_mcspi *mcspi;
744 	struct spi_master *spi_cntrl;
745 	u32 l = 0, div = 0;
746 	u8 word_len = spi->bits_per_word;
747 	u32 speed_hz = spi->max_speed_hz;
748 
749 	mcspi = spi_master_get_devdata(spi->master);
750 	spi_cntrl = mcspi->master;
751 
752 	if (t != NULL && t->bits_per_word)
753 		word_len = t->bits_per_word;
754 
755 	cs->word_len = word_len;
756 
757 	if (t && t->speed_hz)
758 		speed_hz = t->speed_hz;
759 
760 	speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
761 	div = omap2_mcspi_calc_divisor(speed_hz);
762 
763 	l = mcspi_cached_chconf0(spi);
764 
765 	/* standard 4-wire master mode:  SCK, MOSI/out, MISO/in, nCS
766 	 * REVISIT: this controller could support SPI_3WIRE mode.
767 	 */
768 	l &= ~(OMAP2_MCSPI_CHCONF_IS|OMAP2_MCSPI_CHCONF_DPE1);
769 	l |= OMAP2_MCSPI_CHCONF_DPE0;
770 
771 	/* wordlength */
772 	l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
773 	l |= (word_len - 1) << 7;
774 
775 	/* set chipselect polarity; manage with FORCE */
776 	if (!(spi->mode & SPI_CS_HIGH))
777 		l |= OMAP2_MCSPI_CHCONF_EPOL;	/* active-low; normal */
778 	else
779 		l &= ~OMAP2_MCSPI_CHCONF_EPOL;
780 
781 	/* set clock divisor */
782 	l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
783 	l |= div << 2;
784 
785 	/* set SPI mode 0..3 */
786 	if (spi->mode & SPI_CPOL)
787 		l |= OMAP2_MCSPI_CHCONF_POL;
788 	else
789 		l &= ~OMAP2_MCSPI_CHCONF_POL;
790 	if (spi->mode & SPI_CPHA)
791 		l |= OMAP2_MCSPI_CHCONF_PHA;
792 	else
793 		l &= ~OMAP2_MCSPI_CHCONF_PHA;
794 
795 	mcspi_write_chconf0(spi, l);
796 
797 	dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
798 			OMAP2_MCSPI_MAX_FREQ >> div,
799 			(spi->mode & SPI_CPHA) ? "trailing" : "leading",
800 			(spi->mode & SPI_CPOL) ? "inverted" : "normal");
801 
802 	return 0;
803 }
804 
805 static int omap2_mcspi_request_dma(struct spi_device *spi)
806 {
807 	struct spi_master	*master = spi->master;
808 	struct omap2_mcspi	*mcspi;
809 	struct omap2_mcspi_dma	*mcspi_dma;
810 	dma_cap_mask_t mask;
811 	unsigned sig;
812 
813 	mcspi = spi_master_get_devdata(master);
814 	mcspi_dma = mcspi->dma_channels + spi->chip_select;
815 
816 	init_completion(&mcspi_dma->dma_rx_completion);
817 	init_completion(&mcspi_dma->dma_tx_completion);
818 
819 	dma_cap_zero(mask);
820 	dma_cap_set(DMA_SLAVE, mask);
821 	sig = mcspi_dma->dma_rx_sync_dev;
822 	mcspi_dma->dma_rx = dma_request_channel(mask, omap_dma_filter_fn, &sig);
823 	if (!mcspi_dma->dma_rx) {
824 		dev_err(&spi->dev, "no RX DMA engine channel for McSPI\n");
825 		return -EAGAIN;
826 	}
827 
828 	sig = mcspi_dma->dma_tx_sync_dev;
829 	mcspi_dma->dma_tx = dma_request_channel(mask, omap_dma_filter_fn, &sig);
830 	if (!mcspi_dma->dma_tx) {
831 		dev_err(&spi->dev, "no TX DMA engine channel for McSPI\n");
832 		dma_release_channel(mcspi_dma->dma_rx);
833 		mcspi_dma->dma_rx = NULL;
834 		return -EAGAIN;
835 	}
836 
837 	return 0;
838 }
839 
840 static int omap2_mcspi_setup(struct spi_device *spi)
841 {
842 	int			ret;
843 	struct omap2_mcspi	*mcspi = spi_master_get_devdata(spi->master);
844 	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
845 	struct omap2_mcspi_dma	*mcspi_dma;
846 	struct omap2_mcspi_cs	*cs = spi->controller_state;
847 
848 	if (spi->bits_per_word < 4 || spi->bits_per_word > 32) {
849 		dev_dbg(&spi->dev, "setup: unsupported %d bit words\n",
850 			spi->bits_per_word);
851 		return -EINVAL;
852 	}
853 
854 	mcspi_dma = &mcspi->dma_channels[spi->chip_select];
855 
856 	if (!cs) {
857 		cs = kzalloc(sizeof *cs, GFP_KERNEL);
858 		if (!cs)
859 			return -ENOMEM;
860 		cs->base = mcspi->base + spi->chip_select * 0x14;
861 		cs->phys = mcspi->phys + spi->chip_select * 0x14;
862 		cs->chconf0 = 0;
863 		spi->controller_state = cs;
864 		/* Link this to context save list */
865 		list_add_tail(&cs->node, &ctx->cs);
866 	}
867 
868 	if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) {
869 		ret = omap2_mcspi_request_dma(spi);
870 		if (ret < 0)
871 			return ret;
872 	}
873 
874 	ret = pm_runtime_get_sync(mcspi->dev);
875 	if (ret < 0)
876 		return ret;
877 
878 	ret = omap2_mcspi_setup_transfer(spi, NULL);
879 	pm_runtime_mark_last_busy(mcspi->dev);
880 	pm_runtime_put_autosuspend(mcspi->dev);
881 
882 	return ret;
883 }
884 
885 static void omap2_mcspi_cleanup(struct spi_device *spi)
886 {
887 	struct omap2_mcspi	*mcspi;
888 	struct omap2_mcspi_dma	*mcspi_dma;
889 	struct omap2_mcspi_cs	*cs;
890 
891 	mcspi = spi_master_get_devdata(spi->master);
892 
893 	if (spi->controller_state) {
894 		/* Unlink controller state from context save list */
895 		cs = spi->controller_state;
896 		list_del(&cs->node);
897 
898 		kfree(cs);
899 	}
900 
901 	if (spi->chip_select < spi->master->num_chipselect) {
902 		mcspi_dma = &mcspi->dma_channels[spi->chip_select];
903 
904 		if (mcspi_dma->dma_rx) {
905 			dma_release_channel(mcspi_dma->dma_rx);
906 			mcspi_dma->dma_rx = NULL;
907 		}
908 		if (mcspi_dma->dma_tx) {
909 			dma_release_channel(mcspi_dma->dma_tx);
910 			mcspi_dma->dma_tx = NULL;
911 		}
912 	}
913 }
914 
915 static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m)
916 {
917 
918 	/* We only enable one channel at a time -- the one whose message is
919 	 * -- although this controller would gladly
920 	 * arbitrate among multiple channels.  This corresponds to "single
921 	 * channel" master mode.  As a side effect, we need to manage the
922 	 * chipselect with the FORCE bit ... CS != channel enable.
923 	 */
924 
925 	struct spi_device		*spi;
926 	struct spi_transfer		*t = NULL;
927 	int				cs_active = 0;
928 	struct omap2_mcspi_cs		*cs;
929 	struct omap2_mcspi_device_config *cd;
930 	int				par_override = 0;
931 	int				status = 0;
932 	u32				chconf;
933 
934 	spi = m->spi;
935 	cs = spi->controller_state;
936 	cd = spi->controller_data;
937 
938 	omap2_mcspi_set_enable(spi, 1);
939 	list_for_each_entry(t, &m->transfers, transfer_list) {
940 		if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) {
941 			status = -EINVAL;
942 			break;
943 		}
944 		if (par_override || t->speed_hz || t->bits_per_word) {
945 			par_override = 1;
946 			status = omap2_mcspi_setup_transfer(spi, t);
947 			if (status < 0)
948 				break;
949 			if (!t->speed_hz && !t->bits_per_word)
950 				par_override = 0;
951 		}
952 
953 		if (!cs_active) {
954 			omap2_mcspi_force_cs(spi, 1);
955 			cs_active = 1;
956 		}
957 
958 		chconf = mcspi_cached_chconf0(spi);
959 		chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
960 		chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
961 
962 		if (t->tx_buf == NULL)
963 			chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
964 		else if (t->rx_buf == NULL)
965 			chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
966 
967 		if (cd && cd->turbo_mode && t->tx_buf == NULL) {
968 			/* Turbo mode is for more than one word */
969 			if (t->len > ((cs->word_len + 7) >> 3))
970 				chconf |= OMAP2_MCSPI_CHCONF_TURBO;
971 		}
972 
973 		mcspi_write_chconf0(spi, chconf);
974 
975 		if (t->len) {
976 			unsigned	count;
977 
978 			/* RX_ONLY mode needs dummy data in TX reg */
979 			if (t->tx_buf == NULL)
980 				__raw_writel(0, cs->base
981 						+ OMAP2_MCSPI_TX0);
982 
983 			if (m->is_dma_mapped || t->len >= DMA_MIN_BYTES)
984 				count = omap2_mcspi_txrx_dma(spi, t);
985 			else
986 				count = omap2_mcspi_txrx_pio(spi, t);
987 			m->actual_length += count;
988 
989 			if (count != t->len) {
990 				status = -EIO;
991 				break;
992 			}
993 		}
994 
995 		if (t->delay_usecs)
996 			udelay(t->delay_usecs);
997 
998 		/* ignore the "leave it on after last xfer" hint */
999 		if (t->cs_change) {
1000 			omap2_mcspi_force_cs(spi, 0);
1001 			cs_active = 0;
1002 		}
1003 	}
1004 	/* Restore defaults if they were overriden */
1005 	if (par_override) {
1006 		par_override = 0;
1007 		status = omap2_mcspi_setup_transfer(spi, NULL);
1008 	}
1009 
1010 	if (cs_active)
1011 		omap2_mcspi_force_cs(spi, 0);
1012 
1013 	omap2_mcspi_set_enable(spi, 0);
1014 
1015 	m->status = status;
1016 
1017 }
1018 
1019 static int omap2_mcspi_transfer_one_message(struct spi_master *master,
1020 						struct spi_message *m)
1021 {
1022 	struct omap2_mcspi	*mcspi;
1023 	struct spi_transfer	*t;
1024 
1025 	mcspi = spi_master_get_devdata(master);
1026 	m->actual_length = 0;
1027 	m->status = 0;
1028 
1029 	/* reject invalid messages and transfers */
1030 	if (list_empty(&m->transfers))
1031 		return -EINVAL;
1032 	list_for_each_entry(t, &m->transfers, transfer_list) {
1033 		const void	*tx_buf = t->tx_buf;
1034 		void		*rx_buf = t->rx_buf;
1035 		unsigned	len = t->len;
1036 
1037 		if (t->speed_hz > OMAP2_MCSPI_MAX_FREQ
1038 				|| (len && !(rx_buf || tx_buf))
1039 				|| (t->bits_per_word &&
1040 					(  t->bits_per_word < 4
1041 					|| t->bits_per_word > 32))) {
1042 			dev_dbg(mcspi->dev, "transfer: %d Hz, %d %s%s, %d bpw\n",
1043 					t->speed_hz,
1044 					len,
1045 					tx_buf ? "tx" : "",
1046 					rx_buf ? "rx" : "",
1047 					t->bits_per_word);
1048 			return -EINVAL;
1049 		}
1050 		if (t->speed_hz && t->speed_hz < (OMAP2_MCSPI_MAX_FREQ >> 15)) {
1051 			dev_dbg(mcspi->dev, "speed_hz %d below minimum %d Hz\n",
1052 				t->speed_hz,
1053 				OMAP2_MCSPI_MAX_FREQ >> 15);
1054 			return -EINVAL;
1055 		}
1056 
1057 		if (m->is_dma_mapped || len < DMA_MIN_BYTES)
1058 			continue;
1059 
1060 		if (tx_buf != NULL) {
1061 			t->tx_dma = dma_map_single(mcspi->dev, (void *) tx_buf,
1062 					len, DMA_TO_DEVICE);
1063 			if (dma_mapping_error(mcspi->dev, t->tx_dma)) {
1064 				dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1065 						'T', len);
1066 				return -EINVAL;
1067 			}
1068 		}
1069 		if (rx_buf != NULL) {
1070 			t->rx_dma = dma_map_single(mcspi->dev, rx_buf, t->len,
1071 					DMA_FROM_DEVICE);
1072 			if (dma_mapping_error(mcspi->dev, t->rx_dma)) {
1073 				dev_dbg(mcspi->dev, "dma %cX %d bytes error\n",
1074 						'R', len);
1075 				if (tx_buf != NULL)
1076 					dma_unmap_single(mcspi->dev, t->tx_dma,
1077 							len, DMA_TO_DEVICE);
1078 				return -EINVAL;
1079 			}
1080 		}
1081 	}
1082 
1083 	omap2_mcspi_work(mcspi, m);
1084 	spi_finalize_current_message(master);
1085 	return 0;
1086 }
1087 
1088 static int __devinit omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
1089 {
1090 	struct spi_master	*master = mcspi->master;
1091 	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1092 	int			ret = 0;
1093 
1094 	ret = pm_runtime_get_sync(mcspi->dev);
1095 	if (ret < 0)
1096 		return ret;
1097 
1098 	mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1099 				OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1100 	ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1101 
1102 	omap2_mcspi_set_master_mode(master);
1103 	pm_runtime_mark_last_busy(mcspi->dev);
1104 	pm_runtime_put_autosuspend(mcspi->dev);
1105 	return 0;
1106 }
1107 
1108 static int omap_mcspi_runtime_resume(struct device *dev)
1109 {
1110 	struct omap2_mcspi	*mcspi;
1111 	struct spi_master	*master;
1112 
1113 	master = dev_get_drvdata(dev);
1114 	mcspi = spi_master_get_devdata(master);
1115 	omap2_mcspi_restore_ctx(mcspi);
1116 
1117 	return 0;
1118 }
1119 
1120 static struct omap2_mcspi_platform_config omap2_pdata = {
1121 	.regs_offset = 0,
1122 };
1123 
1124 static struct omap2_mcspi_platform_config omap4_pdata = {
1125 	.regs_offset = OMAP4_MCSPI_REG_OFFSET,
1126 };
1127 
1128 static const struct of_device_id omap_mcspi_of_match[] = {
1129 	{
1130 		.compatible = "ti,omap2-mcspi",
1131 		.data = &omap2_pdata,
1132 	},
1133 	{
1134 		.compatible = "ti,omap4-mcspi",
1135 		.data = &omap4_pdata,
1136 	},
1137 	{ },
1138 };
1139 MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1140 
1141 static int __devinit omap2_mcspi_probe(struct platform_device *pdev)
1142 {
1143 	struct spi_master	*master;
1144 	const struct omap2_mcspi_platform_config *pdata;
1145 	struct omap2_mcspi	*mcspi;
1146 	struct resource		*r;
1147 	int			status = 0, i;
1148 	u32			regs_offset = 0;
1149 	static int		bus_num = 1;
1150 	struct device_node	*node = pdev->dev.of_node;
1151 	const struct of_device_id *match;
1152 	struct pinctrl *pinctrl;
1153 
1154 	master = spi_alloc_master(&pdev->dev, sizeof *mcspi);
1155 	if (master == NULL) {
1156 		dev_dbg(&pdev->dev, "master allocation failed\n");
1157 		return -ENOMEM;
1158 	}
1159 
1160 	/* the spi->mode bits understood by this driver: */
1161 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1162 
1163 	master->setup = omap2_mcspi_setup;
1164 	master->prepare_transfer_hardware = omap2_prepare_transfer;
1165 	master->unprepare_transfer_hardware = omap2_unprepare_transfer;
1166 	master->transfer_one_message = omap2_mcspi_transfer_one_message;
1167 	master->cleanup = omap2_mcspi_cleanup;
1168 	master->dev.of_node = node;
1169 
1170 	match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1171 	if (match) {
1172 		u32 num_cs = 1; /* default number of chipselect */
1173 		pdata = match->data;
1174 
1175 		of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1176 		master->num_chipselect = num_cs;
1177 		master->bus_num = bus_num++;
1178 	} else {
1179 		pdata = pdev->dev.platform_data;
1180 		master->num_chipselect = pdata->num_cs;
1181 		if (pdev->id != -1)
1182 			master->bus_num = pdev->id;
1183 	}
1184 	regs_offset = pdata->regs_offset;
1185 
1186 	dev_set_drvdata(&pdev->dev, master);
1187 
1188 	mcspi = spi_master_get_devdata(master);
1189 	mcspi->master = master;
1190 
1191 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1192 	if (r == NULL) {
1193 		status = -ENODEV;
1194 		goto free_master;
1195 	}
1196 
1197 	r->start += regs_offset;
1198 	r->end += regs_offset;
1199 	mcspi->phys = r->start;
1200 
1201 	mcspi->base = devm_request_and_ioremap(&pdev->dev, r);
1202 	if (!mcspi->base) {
1203 		dev_dbg(&pdev->dev, "can't ioremap MCSPI\n");
1204 		status = -ENOMEM;
1205 		goto free_master;
1206 	}
1207 
1208 	mcspi->dev = &pdev->dev;
1209 
1210 	INIT_LIST_HEAD(&mcspi->ctx.cs);
1211 
1212 	mcspi->dma_channels = kcalloc(master->num_chipselect,
1213 			sizeof(struct omap2_mcspi_dma),
1214 			GFP_KERNEL);
1215 
1216 	if (mcspi->dma_channels == NULL)
1217 		goto free_master;
1218 
1219 	for (i = 0; i < master->num_chipselect; i++) {
1220 		char dma_ch_name[14];
1221 		struct resource *dma_res;
1222 
1223 		sprintf(dma_ch_name, "rx%d", i);
1224 		dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA,
1225 							dma_ch_name);
1226 		if (!dma_res) {
1227 			dev_dbg(&pdev->dev, "cannot get DMA RX channel\n");
1228 			status = -ENODEV;
1229 			break;
1230 		}
1231 
1232 		mcspi->dma_channels[i].dma_rx_sync_dev = dma_res->start;
1233 		sprintf(dma_ch_name, "tx%d", i);
1234 		dma_res = platform_get_resource_byname(pdev, IORESOURCE_DMA,
1235 							dma_ch_name);
1236 		if (!dma_res) {
1237 			dev_dbg(&pdev->dev, "cannot get DMA TX channel\n");
1238 			status = -ENODEV;
1239 			break;
1240 		}
1241 
1242 		mcspi->dma_channels[i].dma_tx_sync_dev = dma_res->start;
1243 	}
1244 
1245 	if (status < 0)
1246 		goto dma_chnl_free;
1247 
1248 	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
1249 	if (IS_ERR(pinctrl))
1250 		dev_warn(&pdev->dev,
1251 			"pins are not configured from the driver\n");
1252 
1253 	pm_runtime_use_autosuspend(&pdev->dev);
1254 	pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1255 	pm_runtime_enable(&pdev->dev);
1256 
1257 	if (status || omap2_mcspi_master_setup(mcspi) < 0)
1258 		goto disable_pm;
1259 
1260 	status = spi_register_master(master);
1261 	if (status < 0)
1262 		goto disable_pm;
1263 
1264 	return status;
1265 
1266 disable_pm:
1267 	pm_runtime_disable(&pdev->dev);
1268 dma_chnl_free:
1269 	kfree(mcspi->dma_channels);
1270 free_master:
1271 	spi_master_put(master);
1272 	return status;
1273 }
1274 
1275 static int __devexit omap2_mcspi_remove(struct platform_device *pdev)
1276 {
1277 	struct spi_master	*master;
1278 	struct omap2_mcspi	*mcspi;
1279 	struct omap2_mcspi_dma	*dma_channels;
1280 
1281 	master = dev_get_drvdata(&pdev->dev);
1282 	mcspi = spi_master_get_devdata(master);
1283 	dma_channels = mcspi->dma_channels;
1284 
1285 	pm_runtime_put_sync(mcspi->dev);
1286 	pm_runtime_disable(&pdev->dev);
1287 
1288 	spi_unregister_master(master);
1289 	kfree(dma_channels);
1290 
1291 	return 0;
1292 }
1293 
1294 /* work with hotplug and coldplug */
1295 MODULE_ALIAS("platform:omap2_mcspi");
1296 
1297 #ifdef	CONFIG_SUSPEND
1298 /*
1299  * When SPI wake up from off-mode, CS is in activate state. If it was in
1300  * unactive state when driver was suspend, then force it to unactive state at
1301  * wake up.
1302  */
1303 static int omap2_mcspi_resume(struct device *dev)
1304 {
1305 	struct spi_master	*master = dev_get_drvdata(dev);
1306 	struct omap2_mcspi	*mcspi = spi_master_get_devdata(master);
1307 	struct omap2_mcspi_regs	*ctx = &mcspi->ctx;
1308 	struct omap2_mcspi_cs	*cs;
1309 
1310 	pm_runtime_get_sync(mcspi->dev);
1311 	list_for_each_entry(cs, &ctx->cs, node) {
1312 		if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1313 			/*
1314 			 * We need to toggle CS state for OMAP take this
1315 			 * change in account.
1316 			 */
1317 			cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1318 			__raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1319 			cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1320 			__raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1321 		}
1322 	}
1323 	pm_runtime_mark_last_busy(mcspi->dev);
1324 	pm_runtime_put_autosuspend(mcspi->dev);
1325 	return 0;
1326 }
1327 #else
1328 #define	omap2_mcspi_resume	NULL
1329 #endif
1330 
1331 static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1332 	.resume = omap2_mcspi_resume,
1333 	.runtime_resume	= omap_mcspi_runtime_resume,
1334 };
1335 
1336 static struct platform_driver omap2_mcspi_driver = {
1337 	.driver = {
1338 		.name =		"omap2_mcspi",
1339 		.owner =	THIS_MODULE,
1340 		.pm =		&omap2_mcspi_pm_ops,
1341 		.of_match_table = omap_mcspi_of_match,
1342 	},
1343 	.probe =	omap2_mcspi_probe,
1344 	.remove =	__devexit_p(omap2_mcspi_remove),
1345 };
1346 
1347 module_platform_driver(omap2_mcspi_driver);
1348 MODULE_LICENSE("GPL");
1349