xref: /openbmc/linux/drivers/mmc/host/mxs-mmc.c (revision 92a76f6d)
1 /*
2  * Portions copyright (C) 2003 Russell King, PXA MMCI Driver
3  * Portions copyright (C) 2004-2005 Pierre Ossman, W83L51xD SD/MMC driver
4  *
5  * Copyright 2008 Embedded Alley Solutions, Inc.
6  * Copyright 2009-2011 Freescale Semiconductor, Inc.
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 along
19  * with this program; if not, write to the Free Software Foundation, Inc.,
20  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
21  */
22 
23 #include <linux/kernel.h>
24 #include <linux/init.h>
25 #include <linux/ioport.h>
26 #include <linux/of.h>
27 #include <linux/of_device.h>
28 #include <linux/of_gpio.h>
29 #include <linux/platform_device.h>
30 #include <linux/delay.h>
31 #include <linux/interrupt.h>
32 #include <linux/dma-mapping.h>
33 #include <linux/dmaengine.h>
34 #include <linux/highmem.h>
35 #include <linux/clk.h>
36 #include <linux/err.h>
37 #include <linux/completion.h>
38 #include <linux/mmc/host.h>
39 #include <linux/mmc/mmc.h>
40 #include <linux/mmc/sdio.h>
41 #include <linux/mmc/slot-gpio.h>
42 #include <linux/gpio.h>
43 #include <linux/regulator/consumer.h>
44 #include <linux/module.h>
45 #include <linux/stmp_device.h>
46 #include <linux/spi/mxs-spi.h>
47 
48 #define DRIVER_NAME	"mxs-mmc"
49 
50 #define MXS_MMC_IRQ_BITS	(BM_SSP_CTRL1_SDIO_IRQ		| \
51 				 BM_SSP_CTRL1_RESP_ERR_IRQ	| \
52 				 BM_SSP_CTRL1_RESP_TIMEOUT_IRQ	| \
53 				 BM_SSP_CTRL1_DATA_TIMEOUT_IRQ	| \
54 				 BM_SSP_CTRL1_DATA_CRC_IRQ	| \
55 				 BM_SSP_CTRL1_FIFO_UNDERRUN_IRQ	| \
56 				 BM_SSP_CTRL1_RECV_TIMEOUT_IRQ  | \
57 				 BM_SSP_CTRL1_FIFO_OVERRUN_IRQ)
58 
59 /* card detect polling timeout */
60 #define MXS_MMC_DETECT_TIMEOUT			(HZ/2)
61 
62 struct mxs_mmc_host {
63 	struct mxs_ssp			ssp;
64 
65 	struct mmc_host			*mmc;
66 	struct mmc_request		*mrq;
67 	struct mmc_command		*cmd;
68 	struct mmc_data			*data;
69 
70 	unsigned char			bus_width;
71 	spinlock_t			lock;
72 	int				sdio_irq_en;
73 	bool				broken_cd;
74 };
75 
76 static int mxs_mmc_get_cd(struct mmc_host *mmc)
77 {
78 	struct mxs_mmc_host *host = mmc_priv(mmc);
79 	struct mxs_ssp *ssp = &host->ssp;
80 	int present, ret;
81 
82 	if (host->broken_cd)
83 		return -ENOSYS;
84 
85 	ret = mmc_gpio_get_cd(mmc);
86 	if (ret >= 0)
87 		return ret;
88 
89 	present = mmc->caps & MMC_CAP_NEEDS_POLL ||
90 		!(readl(ssp->base + HW_SSP_STATUS(ssp)) &
91 			BM_SSP_STATUS_CARD_DETECT);
92 
93 	if (mmc->caps2 & MMC_CAP2_CD_ACTIVE_HIGH)
94 		present = !present;
95 
96 	return present;
97 }
98 
99 static int mxs_mmc_reset(struct mxs_mmc_host *host)
100 {
101 	struct mxs_ssp *ssp = &host->ssp;
102 	u32 ctrl0, ctrl1;
103 	int ret;
104 
105 	ret = stmp_reset_block(ssp->base);
106 	if (ret)
107 		return ret;
108 
109 	ctrl0 = BM_SSP_CTRL0_IGNORE_CRC;
110 	ctrl1 = BF_SSP(0x3, CTRL1_SSP_MODE) |
111 		BF_SSP(0x7, CTRL1_WORD_LENGTH) |
112 		BM_SSP_CTRL1_DMA_ENABLE |
113 		BM_SSP_CTRL1_POLARITY |
114 		BM_SSP_CTRL1_RECV_TIMEOUT_IRQ_EN |
115 		BM_SSP_CTRL1_DATA_CRC_IRQ_EN |
116 		BM_SSP_CTRL1_DATA_TIMEOUT_IRQ_EN |
117 		BM_SSP_CTRL1_RESP_TIMEOUT_IRQ_EN |
118 		BM_SSP_CTRL1_RESP_ERR_IRQ_EN;
119 
120 	writel(BF_SSP(0xffff, TIMING_TIMEOUT) |
121 	       BF_SSP(2, TIMING_CLOCK_DIVIDE) |
122 	       BF_SSP(0, TIMING_CLOCK_RATE),
123 	       ssp->base + HW_SSP_TIMING(ssp));
124 
125 	if (host->sdio_irq_en) {
126 		ctrl0 |= BM_SSP_CTRL0_SDIO_IRQ_CHECK;
127 		ctrl1 |= BM_SSP_CTRL1_SDIO_IRQ_EN;
128 	}
129 
130 	writel(ctrl0, ssp->base + HW_SSP_CTRL0);
131 	writel(ctrl1, ssp->base + HW_SSP_CTRL1(ssp));
132 	return 0;
133 }
134 
135 static void mxs_mmc_start_cmd(struct mxs_mmc_host *host,
136 			      struct mmc_command *cmd);
137 
138 static void mxs_mmc_request_done(struct mxs_mmc_host *host)
139 {
140 	struct mmc_command *cmd = host->cmd;
141 	struct mmc_data *data = host->data;
142 	struct mmc_request *mrq = host->mrq;
143 	struct mxs_ssp *ssp = &host->ssp;
144 
145 	if (mmc_resp_type(cmd) & MMC_RSP_PRESENT) {
146 		if (mmc_resp_type(cmd) & MMC_RSP_136) {
147 			cmd->resp[3] = readl(ssp->base + HW_SSP_SDRESP0(ssp));
148 			cmd->resp[2] = readl(ssp->base + HW_SSP_SDRESP1(ssp));
149 			cmd->resp[1] = readl(ssp->base + HW_SSP_SDRESP2(ssp));
150 			cmd->resp[0] = readl(ssp->base + HW_SSP_SDRESP3(ssp));
151 		} else {
152 			cmd->resp[0] = readl(ssp->base + HW_SSP_SDRESP0(ssp));
153 		}
154 	}
155 
156 	if (data) {
157 		dma_unmap_sg(mmc_dev(host->mmc), data->sg,
158 			     data->sg_len, ssp->dma_dir);
159 		/*
160 		 * If there was an error on any block, we mark all
161 		 * data blocks as being in error.
162 		 */
163 		if (!data->error)
164 			data->bytes_xfered = data->blocks * data->blksz;
165 		else
166 			data->bytes_xfered = 0;
167 
168 		host->data = NULL;
169 		if (mrq->stop) {
170 			mxs_mmc_start_cmd(host, mrq->stop);
171 			return;
172 		}
173 	}
174 
175 	host->mrq = NULL;
176 	mmc_request_done(host->mmc, mrq);
177 }
178 
179 static void mxs_mmc_dma_irq_callback(void *param)
180 {
181 	struct mxs_mmc_host *host = param;
182 
183 	mxs_mmc_request_done(host);
184 }
185 
186 static irqreturn_t mxs_mmc_irq_handler(int irq, void *dev_id)
187 {
188 	struct mxs_mmc_host *host = dev_id;
189 	struct mmc_command *cmd = host->cmd;
190 	struct mmc_data *data = host->data;
191 	struct mxs_ssp *ssp = &host->ssp;
192 	u32 stat;
193 
194 	spin_lock(&host->lock);
195 
196 	stat = readl(ssp->base + HW_SSP_CTRL1(ssp));
197 	writel(stat & MXS_MMC_IRQ_BITS,
198 	       ssp->base + HW_SSP_CTRL1(ssp) + STMP_OFFSET_REG_CLR);
199 
200 	spin_unlock(&host->lock);
201 
202 	if ((stat & BM_SSP_CTRL1_SDIO_IRQ) && (stat & BM_SSP_CTRL1_SDIO_IRQ_EN))
203 		mmc_signal_sdio_irq(host->mmc);
204 
205 	if (stat & BM_SSP_CTRL1_RESP_TIMEOUT_IRQ)
206 		cmd->error = -ETIMEDOUT;
207 	else if (stat & BM_SSP_CTRL1_RESP_ERR_IRQ)
208 		cmd->error = -EIO;
209 
210 	if (data) {
211 		if (stat & (BM_SSP_CTRL1_DATA_TIMEOUT_IRQ |
212 			    BM_SSP_CTRL1_RECV_TIMEOUT_IRQ))
213 			data->error = -ETIMEDOUT;
214 		else if (stat & BM_SSP_CTRL1_DATA_CRC_IRQ)
215 			data->error = -EILSEQ;
216 		else if (stat & (BM_SSP_CTRL1_FIFO_UNDERRUN_IRQ |
217 				 BM_SSP_CTRL1_FIFO_OVERRUN_IRQ))
218 			data->error = -EIO;
219 	}
220 
221 	return IRQ_HANDLED;
222 }
223 
224 static struct dma_async_tx_descriptor *mxs_mmc_prep_dma(
225 	struct mxs_mmc_host *host, unsigned long flags)
226 {
227 	struct mxs_ssp *ssp = &host->ssp;
228 	struct dma_async_tx_descriptor *desc;
229 	struct mmc_data *data = host->data;
230 	struct scatterlist * sgl;
231 	unsigned int sg_len;
232 
233 	if (data) {
234 		/* data */
235 		dma_map_sg(mmc_dev(host->mmc), data->sg,
236 			   data->sg_len, ssp->dma_dir);
237 		sgl = data->sg;
238 		sg_len = data->sg_len;
239 	} else {
240 		/* pio */
241 		sgl = (struct scatterlist *) ssp->ssp_pio_words;
242 		sg_len = SSP_PIO_NUM;
243 	}
244 
245 	desc = dmaengine_prep_slave_sg(ssp->dmach,
246 				sgl, sg_len, ssp->slave_dirn, flags);
247 	if (desc) {
248 		desc->callback = mxs_mmc_dma_irq_callback;
249 		desc->callback_param = host;
250 	} else {
251 		if (data)
252 			dma_unmap_sg(mmc_dev(host->mmc), data->sg,
253 				     data->sg_len, ssp->dma_dir);
254 	}
255 
256 	return desc;
257 }
258 
259 static void mxs_mmc_bc(struct mxs_mmc_host *host)
260 {
261 	struct mxs_ssp *ssp = &host->ssp;
262 	struct mmc_command *cmd = host->cmd;
263 	struct dma_async_tx_descriptor *desc;
264 	u32 ctrl0, cmd0, cmd1;
265 
266 	ctrl0 = BM_SSP_CTRL0_ENABLE | BM_SSP_CTRL0_IGNORE_CRC;
267 	cmd0 = BF_SSP(cmd->opcode, CMD0_CMD) | BM_SSP_CMD0_APPEND_8CYC;
268 	cmd1 = cmd->arg;
269 
270 	if (host->sdio_irq_en) {
271 		ctrl0 |= BM_SSP_CTRL0_SDIO_IRQ_CHECK;
272 		cmd0 |= BM_SSP_CMD0_CONT_CLKING_EN | BM_SSP_CMD0_SLOW_CLKING_EN;
273 	}
274 
275 	ssp->ssp_pio_words[0] = ctrl0;
276 	ssp->ssp_pio_words[1] = cmd0;
277 	ssp->ssp_pio_words[2] = cmd1;
278 	ssp->dma_dir = DMA_NONE;
279 	ssp->slave_dirn = DMA_TRANS_NONE;
280 	desc = mxs_mmc_prep_dma(host, DMA_CTRL_ACK);
281 	if (!desc)
282 		goto out;
283 
284 	dmaengine_submit(desc);
285 	dma_async_issue_pending(ssp->dmach);
286 	return;
287 
288 out:
289 	dev_warn(mmc_dev(host->mmc),
290 		 "%s: failed to prep dma\n", __func__);
291 }
292 
293 static void mxs_mmc_ac(struct mxs_mmc_host *host)
294 {
295 	struct mxs_ssp *ssp = &host->ssp;
296 	struct mmc_command *cmd = host->cmd;
297 	struct dma_async_tx_descriptor *desc;
298 	u32 ignore_crc, get_resp, long_resp;
299 	u32 ctrl0, cmd0, cmd1;
300 
301 	ignore_crc = (mmc_resp_type(cmd) & MMC_RSP_CRC) ?
302 			0 : BM_SSP_CTRL0_IGNORE_CRC;
303 	get_resp = (mmc_resp_type(cmd) & MMC_RSP_PRESENT) ?
304 			BM_SSP_CTRL0_GET_RESP : 0;
305 	long_resp = (mmc_resp_type(cmd) & MMC_RSP_136) ?
306 			BM_SSP_CTRL0_LONG_RESP : 0;
307 
308 	ctrl0 = BM_SSP_CTRL0_ENABLE | ignore_crc | get_resp | long_resp;
309 	cmd0 = BF_SSP(cmd->opcode, CMD0_CMD);
310 	cmd1 = cmd->arg;
311 
312 	if (host->sdio_irq_en) {
313 		ctrl0 |= BM_SSP_CTRL0_SDIO_IRQ_CHECK;
314 		cmd0 |= BM_SSP_CMD0_CONT_CLKING_EN | BM_SSP_CMD0_SLOW_CLKING_EN;
315 	}
316 
317 	ssp->ssp_pio_words[0] = ctrl0;
318 	ssp->ssp_pio_words[1] = cmd0;
319 	ssp->ssp_pio_words[2] = cmd1;
320 	ssp->dma_dir = DMA_NONE;
321 	ssp->slave_dirn = DMA_TRANS_NONE;
322 	desc = mxs_mmc_prep_dma(host, DMA_CTRL_ACK);
323 	if (!desc)
324 		goto out;
325 
326 	dmaengine_submit(desc);
327 	dma_async_issue_pending(ssp->dmach);
328 	return;
329 
330 out:
331 	dev_warn(mmc_dev(host->mmc),
332 		 "%s: failed to prep dma\n", __func__);
333 }
334 
335 static unsigned short mxs_ns_to_ssp_ticks(unsigned clock_rate, unsigned ns)
336 {
337 	const unsigned int ssp_timeout_mul = 4096;
338 	/*
339 	 * Calculate ticks in ms since ns are large numbers
340 	 * and might overflow
341 	 */
342 	const unsigned int clock_per_ms = clock_rate / 1000;
343 	const unsigned int ms = ns / 1000;
344 	const unsigned int ticks = ms * clock_per_ms;
345 	const unsigned int ssp_ticks = ticks / ssp_timeout_mul;
346 
347 	WARN_ON(ssp_ticks == 0);
348 	return ssp_ticks;
349 }
350 
351 static void mxs_mmc_adtc(struct mxs_mmc_host *host)
352 {
353 	struct mmc_command *cmd = host->cmd;
354 	struct mmc_data *data = cmd->data;
355 	struct dma_async_tx_descriptor *desc;
356 	struct scatterlist *sgl = data->sg, *sg;
357 	unsigned int sg_len = data->sg_len;
358 	unsigned int i;
359 
360 	unsigned short dma_data_dir, timeout;
361 	enum dma_transfer_direction slave_dirn;
362 	unsigned int data_size = 0, log2_blksz;
363 	unsigned int blocks = data->blocks;
364 
365 	struct mxs_ssp *ssp = &host->ssp;
366 
367 	u32 ignore_crc, get_resp, long_resp, read;
368 	u32 ctrl0, cmd0, cmd1, val;
369 
370 	ignore_crc = (mmc_resp_type(cmd) & MMC_RSP_CRC) ?
371 			0 : BM_SSP_CTRL0_IGNORE_CRC;
372 	get_resp = (mmc_resp_type(cmd) & MMC_RSP_PRESENT) ?
373 			BM_SSP_CTRL0_GET_RESP : 0;
374 	long_resp = (mmc_resp_type(cmd) & MMC_RSP_136) ?
375 			BM_SSP_CTRL0_LONG_RESP : 0;
376 
377 	if (data->flags & MMC_DATA_WRITE) {
378 		dma_data_dir = DMA_TO_DEVICE;
379 		slave_dirn = DMA_MEM_TO_DEV;
380 		read = 0;
381 	} else {
382 		dma_data_dir = DMA_FROM_DEVICE;
383 		slave_dirn = DMA_DEV_TO_MEM;
384 		read = BM_SSP_CTRL0_READ;
385 	}
386 
387 	ctrl0 = BF_SSP(host->bus_width, CTRL0_BUS_WIDTH) |
388 		ignore_crc | get_resp | long_resp |
389 		BM_SSP_CTRL0_DATA_XFER | read |
390 		BM_SSP_CTRL0_WAIT_FOR_IRQ |
391 		BM_SSP_CTRL0_ENABLE;
392 
393 	cmd0 = BF_SSP(cmd->opcode, CMD0_CMD);
394 
395 	/* get logarithm to base 2 of block size for setting register */
396 	log2_blksz = ilog2(data->blksz);
397 
398 	/*
399 	 * take special care of the case that data size from data->sg
400 	 * is not equal to blocks x blksz
401 	 */
402 	for_each_sg(sgl, sg, sg_len, i)
403 		data_size += sg->length;
404 
405 	if (data_size != data->blocks * data->blksz)
406 		blocks = 1;
407 
408 	/* xfer count, block size and count need to be set differently */
409 	if (ssp_is_old(ssp)) {
410 		ctrl0 |= BF_SSP(data_size, CTRL0_XFER_COUNT);
411 		cmd0 |= BF_SSP(log2_blksz, CMD0_BLOCK_SIZE) |
412 			BF_SSP(blocks - 1, CMD0_BLOCK_COUNT);
413 	} else {
414 		writel(data_size, ssp->base + HW_SSP_XFER_SIZE);
415 		writel(BF_SSP(log2_blksz, BLOCK_SIZE_BLOCK_SIZE) |
416 		       BF_SSP(blocks - 1, BLOCK_SIZE_BLOCK_COUNT),
417 		       ssp->base + HW_SSP_BLOCK_SIZE);
418 	}
419 
420 	if ((cmd->opcode == MMC_STOP_TRANSMISSION) ||
421 	    (cmd->opcode == SD_IO_RW_EXTENDED))
422 		cmd0 |= BM_SSP_CMD0_APPEND_8CYC;
423 
424 	cmd1 = cmd->arg;
425 
426 	if (host->sdio_irq_en) {
427 		ctrl0 |= BM_SSP_CTRL0_SDIO_IRQ_CHECK;
428 		cmd0 |= BM_SSP_CMD0_CONT_CLKING_EN | BM_SSP_CMD0_SLOW_CLKING_EN;
429 	}
430 
431 	/* set the timeout count */
432 	timeout = mxs_ns_to_ssp_ticks(ssp->clk_rate, data->timeout_ns);
433 	val = readl(ssp->base + HW_SSP_TIMING(ssp));
434 	val &= ~(BM_SSP_TIMING_TIMEOUT);
435 	val |= BF_SSP(timeout, TIMING_TIMEOUT);
436 	writel(val, ssp->base + HW_SSP_TIMING(ssp));
437 
438 	/* pio */
439 	ssp->ssp_pio_words[0] = ctrl0;
440 	ssp->ssp_pio_words[1] = cmd0;
441 	ssp->ssp_pio_words[2] = cmd1;
442 	ssp->dma_dir = DMA_NONE;
443 	ssp->slave_dirn = DMA_TRANS_NONE;
444 	desc = mxs_mmc_prep_dma(host, 0);
445 	if (!desc)
446 		goto out;
447 
448 	/* append data sg */
449 	WARN_ON(host->data != NULL);
450 	host->data = data;
451 	ssp->dma_dir = dma_data_dir;
452 	ssp->slave_dirn = slave_dirn;
453 	desc = mxs_mmc_prep_dma(host, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
454 	if (!desc)
455 		goto out;
456 
457 	dmaengine_submit(desc);
458 	dma_async_issue_pending(ssp->dmach);
459 	return;
460 out:
461 	dev_warn(mmc_dev(host->mmc),
462 		 "%s: failed to prep dma\n", __func__);
463 }
464 
465 static void mxs_mmc_start_cmd(struct mxs_mmc_host *host,
466 			      struct mmc_command *cmd)
467 {
468 	host->cmd = cmd;
469 
470 	switch (mmc_cmd_type(cmd)) {
471 	case MMC_CMD_BC:
472 		mxs_mmc_bc(host);
473 		break;
474 	case MMC_CMD_BCR:
475 		mxs_mmc_ac(host);
476 		break;
477 	case MMC_CMD_AC:
478 		mxs_mmc_ac(host);
479 		break;
480 	case MMC_CMD_ADTC:
481 		mxs_mmc_adtc(host);
482 		break;
483 	default:
484 		dev_warn(mmc_dev(host->mmc),
485 			 "%s: unknown MMC command\n", __func__);
486 		break;
487 	}
488 }
489 
490 static void mxs_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
491 {
492 	struct mxs_mmc_host *host = mmc_priv(mmc);
493 
494 	WARN_ON(host->mrq != NULL);
495 	host->mrq = mrq;
496 	mxs_mmc_start_cmd(host, mrq->cmd);
497 }
498 
499 static void mxs_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
500 {
501 	struct mxs_mmc_host *host = mmc_priv(mmc);
502 
503 	if (ios->bus_width == MMC_BUS_WIDTH_8)
504 		host->bus_width = 2;
505 	else if (ios->bus_width == MMC_BUS_WIDTH_4)
506 		host->bus_width = 1;
507 	else
508 		host->bus_width = 0;
509 
510 	if (ios->clock)
511 		mxs_ssp_set_clk_rate(&host->ssp, ios->clock);
512 }
513 
514 static void mxs_mmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
515 {
516 	struct mxs_mmc_host *host = mmc_priv(mmc);
517 	struct mxs_ssp *ssp = &host->ssp;
518 	unsigned long flags;
519 
520 	spin_lock_irqsave(&host->lock, flags);
521 
522 	host->sdio_irq_en = enable;
523 
524 	if (enable) {
525 		writel(BM_SSP_CTRL0_SDIO_IRQ_CHECK,
526 		       ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET);
527 		writel(BM_SSP_CTRL1_SDIO_IRQ_EN,
528 		       ssp->base + HW_SSP_CTRL1(ssp) + STMP_OFFSET_REG_SET);
529 	} else {
530 		writel(BM_SSP_CTRL0_SDIO_IRQ_CHECK,
531 		       ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR);
532 		writel(BM_SSP_CTRL1_SDIO_IRQ_EN,
533 		       ssp->base + HW_SSP_CTRL1(ssp) + STMP_OFFSET_REG_CLR);
534 	}
535 
536 	spin_unlock_irqrestore(&host->lock, flags);
537 
538 	if (enable && readl(ssp->base + HW_SSP_STATUS(ssp)) &
539 			BM_SSP_STATUS_SDIO_IRQ)
540 		mmc_signal_sdio_irq(host->mmc);
541 
542 }
543 
544 static const struct mmc_host_ops mxs_mmc_ops = {
545 	.request = mxs_mmc_request,
546 	.get_ro = mmc_gpio_get_ro,
547 	.get_cd = mxs_mmc_get_cd,
548 	.set_ios = mxs_mmc_set_ios,
549 	.enable_sdio_irq = mxs_mmc_enable_sdio_irq,
550 };
551 
552 static const struct platform_device_id mxs_ssp_ids[] = {
553 	{
554 		.name = "imx23-mmc",
555 		.driver_data = IMX23_SSP,
556 	}, {
557 		.name = "imx28-mmc",
558 		.driver_data = IMX28_SSP,
559 	}, {
560 		/* sentinel */
561 	}
562 };
563 MODULE_DEVICE_TABLE(platform, mxs_ssp_ids);
564 
565 static const struct of_device_id mxs_mmc_dt_ids[] = {
566 	{ .compatible = "fsl,imx23-mmc", .data = (void *) IMX23_SSP, },
567 	{ .compatible = "fsl,imx28-mmc", .data = (void *) IMX28_SSP, },
568 	{ /* sentinel */ }
569 };
570 MODULE_DEVICE_TABLE(of, mxs_mmc_dt_ids);
571 
572 static int mxs_mmc_probe(struct platform_device *pdev)
573 {
574 	const struct of_device_id *of_id =
575 			of_match_device(mxs_mmc_dt_ids, &pdev->dev);
576 	struct device_node *np = pdev->dev.of_node;
577 	struct mxs_mmc_host *host;
578 	struct mmc_host *mmc;
579 	struct resource *iores;
580 	int ret = 0, irq_err;
581 	struct regulator *reg_vmmc;
582 	struct mxs_ssp *ssp;
583 
584 	irq_err = platform_get_irq(pdev, 0);
585 	if (irq_err < 0)
586 		return irq_err;
587 
588 	mmc = mmc_alloc_host(sizeof(struct mxs_mmc_host), &pdev->dev);
589 	if (!mmc)
590 		return -ENOMEM;
591 
592 	host = mmc_priv(mmc);
593 	ssp = &host->ssp;
594 	ssp->dev = &pdev->dev;
595 	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
596 	ssp->base = devm_ioremap_resource(&pdev->dev, iores);
597 	if (IS_ERR(ssp->base)) {
598 		ret = PTR_ERR(ssp->base);
599 		goto out_mmc_free;
600 	}
601 
602 	ssp->devid = (enum mxs_ssp_id) of_id->data;
603 
604 	host->mmc = mmc;
605 	host->sdio_irq_en = 0;
606 
607 	reg_vmmc = devm_regulator_get(&pdev->dev, "vmmc");
608 	if (!IS_ERR(reg_vmmc)) {
609 		ret = regulator_enable(reg_vmmc);
610 		if (ret) {
611 			dev_err(&pdev->dev,
612 				"Failed to enable vmmc regulator: %d\n", ret);
613 			goto out_mmc_free;
614 		}
615 	}
616 
617 	ssp->clk = devm_clk_get(&pdev->dev, NULL);
618 	if (IS_ERR(ssp->clk)) {
619 		ret = PTR_ERR(ssp->clk);
620 		goto out_mmc_free;
621 	}
622 	ret = clk_prepare_enable(ssp->clk);
623 	if (ret)
624 		goto out_mmc_free;
625 
626 	ret = mxs_mmc_reset(host);
627 	if (ret) {
628 		dev_err(&pdev->dev, "Failed to reset mmc: %d\n", ret);
629 		goto out_clk_disable;
630 	}
631 
632 	ssp->dmach = dma_request_slave_channel(&pdev->dev, "rx-tx");
633 	if (!ssp->dmach) {
634 		dev_err(mmc_dev(host->mmc),
635 			"%s: failed to request dma\n", __func__);
636 		ret = -ENODEV;
637 		goto out_clk_disable;
638 	}
639 
640 	/* set mmc core parameters */
641 	mmc->ops = &mxs_mmc_ops;
642 	mmc->caps = MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED |
643 		    MMC_CAP_SDIO_IRQ | MMC_CAP_NEEDS_POLL;
644 
645 	host->broken_cd = of_property_read_bool(np, "broken-cd");
646 
647 	mmc->f_min = 400000;
648 	mmc->f_max = 288000000;
649 
650 	ret = mmc_of_parse(mmc);
651 	if (ret)
652 		goto out_clk_disable;
653 
654 	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
655 
656 	mmc->max_segs = 52;
657 	mmc->max_blk_size = 1 << 0xf;
658 	mmc->max_blk_count = (ssp_is_old(ssp)) ? 0xff : 0xffffff;
659 	mmc->max_req_size = (ssp_is_old(ssp)) ? 0xffff : 0xffffffff;
660 	mmc->max_seg_size = dma_get_max_seg_size(ssp->dmach->device->dev);
661 
662 	platform_set_drvdata(pdev, mmc);
663 
664 	ret = devm_request_irq(&pdev->dev, irq_err, mxs_mmc_irq_handler, 0,
665 			       dev_name(&pdev->dev), host);
666 	if (ret)
667 		goto out_free_dma;
668 
669 	spin_lock_init(&host->lock);
670 
671 	ret = mmc_add_host(mmc);
672 	if (ret)
673 		goto out_free_dma;
674 
675 	dev_info(mmc_dev(host->mmc), "initialized\n");
676 
677 	return 0;
678 
679 out_free_dma:
680 	dma_release_channel(ssp->dmach);
681 out_clk_disable:
682 	clk_disable_unprepare(ssp->clk);
683 out_mmc_free:
684 	mmc_free_host(mmc);
685 	return ret;
686 }
687 
688 static int mxs_mmc_remove(struct platform_device *pdev)
689 {
690 	struct mmc_host *mmc = platform_get_drvdata(pdev);
691 	struct mxs_mmc_host *host = mmc_priv(mmc);
692 	struct mxs_ssp *ssp = &host->ssp;
693 
694 	mmc_remove_host(mmc);
695 
696 	if (ssp->dmach)
697 		dma_release_channel(ssp->dmach);
698 
699 	clk_disable_unprepare(ssp->clk);
700 
701 	mmc_free_host(mmc);
702 
703 	return 0;
704 }
705 
706 #ifdef CONFIG_PM_SLEEP
707 static int mxs_mmc_suspend(struct device *dev)
708 {
709 	struct mmc_host *mmc = dev_get_drvdata(dev);
710 	struct mxs_mmc_host *host = mmc_priv(mmc);
711 	struct mxs_ssp *ssp = &host->ssp;
712 
713 	clk_disable_unprepare(ssp->clk);
714 	return 0;
715 }
716 
717 static int mxs_mmc_resume(struct device *dev)
718 {
719 	struct mmc_host *mmc = dev_get_drvdata(dev);
720 	struct mxs_mmc_host *host = mmc_priv(mmc);
721 	struct mxs_ssp *ssp = &host->ssp;
722 
723 	return clk_prepare_enable(ssp->clk);
724 }
725 #endif
726 
727 static SIMPLE_DEV_PM_OPS(mxs_mmc_pm_ops, mxs_mmc_suspend, mxs_mmc_resume);
728 
729 static struct platform_driver mxs_mmc_driver = {
730 	.probe		= mxs_mmc_probe,
731 	.remove		= mxs_mmc_remove,
732 	.id_table	= mxs_ssp_ids,
733 	.driver		= {
734 		.name	= DRIVER_NAME,
735 		.pm	= &mxs_mmc_pm_ops,
736 		.of_match_table = mxs_mmc_dt_ids,
737 	},
738 };
739 
740 module_platform_driver(mxs_mmc_driver);
741 
742 MODULE_DESCRIPTION("FREESCALE MXS MMC peripheral");
743 MODULE_AUTHOR("Freescale Semiconductor");
744 MODULE_LICENSE("GPL");
745 MODULE_ALIAS("platform:" DRIVER_NAME);
746