xref: /linux/drivers/mmc/host/mxs-mmc.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Portions copyright (C) 2003 Russell King, PXA MMCI Driver
4  * Portions copyright (C) 2004-2005 Pierre Ossman, W83L51xD SD/MMC driver
5  *
6  * Copyright 2008 Embedded Alley Solutions, Inc.
7  * Copyright 2009-2011 Freescale Semiconductor, Inc.
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/ioport.h>
13 #include <linux/of.h>
14 #include <linux/platform_device.h>
15 #include <linux/delay.h>
16 #include <linux/interrupt.h>
17 #include <linux/dma-mapping.h>
18 #include <linux/dmaengine.h>
19 #include <linux/dma/mxs-dma.h>
20 #include <linux/highmem.h>
21 #include <linux/clk.h>
22 #include <linux/err.h>
23 #include <linux/completion.h>
24 #include <linux/mmc/host.h>
25 #include <linux/mmc/mmc.h>
26 #include <linux/mmc/sdio.h>
27 #include <linux/mmc/slot-gpio.h>
28 #include <linux/regulator/consumer.h>
29 #include <linux/module.h>
30 #include <linux/stmp_device.h>
31 #include <linux/spi/mxs-spi.h>
32 
33 #define DRIVER_NAME	"mxs-mmc"
34 
35 #define MXS_MMC_IRQ_BITS	(BM_SSP_CTRL1_SDIO_IRQ		| \
36 				 BM_SSP_CTRL1_RESP_ERR_IRQ	| \
37 				 BM_SSP_CTRL1_RESP_TIMEOUT_IRQ	| \
38 				 BM_SSP_CTRL1_DATA_TIMEOUT_IRQ	| \
39 				 BM_SSP_CTRL1_DATA_CRC_IRQ	| \
40 				 BM_SSP_CTRL1_FIFO_UNDERRUN_IRQ	| \
41 				 BM_SSP_CTRL1_RECV_TIMEOUT_IRQ  | \
42 				 BM_SSP_CTRL1_FIFO_OVERRUN_IRQ)
43 
44 /* card detect polling timeout */
45 #define MXS_MMC_DETECT_TIMEOUT			(HZ/2)
46 
47 struct mxs_mmc_host {
48 	struct mxs_ssp			ssp;
49 
50 	struct mmc_host			*mmc;
51 	struct mmc_request		*mrq;
52 	struct mmc_command		*cmd;
53 	struct mmc_data			*data;
54 
55 	unsigned char			bus_width;
56 	spinlock_t			lock;
57 	int				sdio_irq_en;
58 	bool				broken_cd;
59 };
60 
61 static int mxs_mmc_get_cd(struct mmc_host *mmc)
62 {
63 	struct mxs_mmc_host *host = mmc_priv(mmc);
64 	struct mxs_ssp *ssp = &host->ssp;
65 	int present, ret;
66 
67 	if (host->broken_cd)
68 		return -ENOSYS;
69 
70 	ret = mmc_gpio_get_cd(mmc);
71 	if (ret >= 0)
72 		return ret;
73 
74 	present = mmc->caps & MMC_CAP_NEEDS_POLL ||
75 		!(readl(ssp->base + HW_SSP_STATUS(ssp)) &
76 			BM_SSP_STATUS_CARD_DETECT);
77 
78 	if (mmc->caps2 & MMC_CAP2_CD_ACTIVE_HIGH)
79 		present = !present;
80 
81 	return present;
82 }
83 
84 static int mxs_mmc_reset(struct mxs_mmc_host *host)
85 {
86 	struct mxs_ssp *ssp = &host->ssp;
87 	u32 ctrl0, ctrl1;
88 	int ret;
89 
90 	ret = stmp_reset_block(ssp->base);
91 	if (ret)
92 		return ret;
93 
94 	ctrl0 = BM_SSP_CTRL0_IGNORE_CRC;
95 	ctrl1 = BF_SSP(0x3, CTRL1_SSP_MODE) |
96 		BF_SSP(0x7, CTRL1_WORD_LENGTH) |
97 		BM_SSP_CTRL1_DMA_ENABLE |
98 		BM_SSP_CTRL1_POLARITY |
99 		BM_SSP_CTRL1_RECV_TIMEOUT_IRQ_EN |
100 		BM_SSP_CTRL1_DATA_CRC_IRQ_EN |
101 		BM_SSP_CTRL1_DATA_TIMEOUT_IRQ_EN |
102 		BM_SSP_CTRL1_RESP_TIMEOUT_IRQ_EN |
103 		BM_SSP_CTRL1_RESP_ERR_IRQ_EN;
104 
105 	writel(BF_SSP(0xffff, TIMING_TIMEOUT) |
106 	       BF_SSP(2, TIMING_CLOCK_DIVIDE) |
107 	       BF_SSP(0, TIMING_CLOCK_RATE),
108 	       ssp->base + HW_SSP_TIMING(ssp));
109 
110 	if (host->sdio_irq_en) {
111 		ctrl0 |= BM_SSP_CTRL0_SDIO_IRQ_CHECK;
112 		ctrl1 |= BM_SSP_CTRL1_SDIO_IRQ_EN;
113 	}
114 
115 	writel(ctrl0, ssp->base + HW_SSP_CTRL0);
116 	writel(ctrl1, ssp->base + HW_SSP_CTRL1(ssp));
117 	return 0;
118 }
119 
120 static void mxs_mmc_start_cmd(struct mxs_mmc_host *host,
121 			      struct mmc_command *cmd);
122 
123 static void mxs_mmc_request_done(struct mxs_mmc_host *host)
124 {
125 	struct mmc_command *cmd = host->cmd;
126 	struct mmc_data *data = host->data;
127 	struct mmc_request *mrq = host->mrq;
128 	struct mxs_ssp *ssp = &host->ssp;
129 
130 	if (mmc_resp_type(cmd) & MMC_RSP_PRESENT) {
131 		if (mmc_resp_type(cmd) & MMC_RSP_136) {
132 			cmd->resp[3] = readl(ssp->base + HW_SSP_SDRESP0(ssp));
133 			cmd->resp[2] = readl(ssp->base + HW_SSP_SDRESP1(ssp));
134 			cmd->resp[1] = readl(ssp->base + HW_SSP_SDRESP2(ssp));
135 			cmd->resp[0] = readl(ssp->base + HW_SSP_SDRESP3(ssp));
136 		} else {
137 			cmd->resp[0] = readl(ssp->base + HW_SSP_SDRESP0(ssp));
138 		}
139 	}
140 
141 	if (cmd == mrq->sbc) {
142 		/* Finished CMD23, now send actual command. */
143 		mxs_mmc_start_cmd(host, mrq->cmd);
144 		return;
145 	} else if (data) {
146 		dma_unmap_sg(mmc_dev(host->mmc), data->sg,
147 			     data->sg_len, ssp->dma_dir);
148 		/*
149 		 * If there was an error on any block, we mark all
150 		 * data blocks as being in error.
151 		 */
152 		if (!data->error)
153 			data->bytes_xfered = data->blocks * data->blksz;
154 		else
155 			data->bytes_xfered = 0;
156 
157 		host->data = NULL;
158 		if (data->stop && (data->error || !mrq->sbc)) {
159 			mxs_mmc_start_cmd(host, mrq->stop);
160 			return;
161 		}
162 	}
163 
164 	host->mrq = NULL;
165 	mmc_request_done(host->mmc, mrq);
166 }
167 
168 static void mxs_mmc_dma_irq_callback(void *param)
169 {
170 	struct mxs_mmc_host *host = param;
171 
172 	mxs_mmc_request_done(host);
173 }
174 
175 static irqreturn_t mxs_mmc_irq_handler(int irq, void *dev_id)
176 {
177 	struct mxs_mmc_host *host = dev_id;
178 	struct mmc_command *cmd = host->cmd;
179 	struct mmc_data *data = host->data;
180 	struct mxs_ssp *ssp = &host->ssp;
181 	u32 stat;
182 
183 	spin_lock(&host->lock);
184 
185 	stat = readl(ssp->base + HW_SSP_CTRL1(ssp));
186 	writel(stat & MXS_MMC_IRQ_BITS,
187 	       ssp->base + HW_SSP_CTRL1(ssp) + STMP_OFFSET_REG_CLR);
188 
189 	spin_unlock(&host->lock);
190 
191 	if ((stat & BM_SSP_CTRL1_SDIO_IRQ) && (stat & BM_SSP_CTRL1_SDIO_IRQ_EN))
192 		mmc_signal_sdio_irq(host->mmc);
193 
194 	if (stat & BM_SSP_CTRL1_RESP_TIMEOUT_IRQ)
195 		cmd->error = -ETIMEDOUT;
196 	else if (stat & BM_SSP_CTRL1_RESP_ERR_IRQ)
197 		cmd->error = -EIO;
198 
199 	if (data) {
200 		if (stat & (BM_SSP_CTRL1_DATA_TIMEOUT_IRQ |
201 			    BM_SSP_CTRL1_RECV_TIMEOUT_IRQ))
202 			data->error = -ETIMEDOUT;
203 		else if (stat & BM_SSP_CTRL1_DATA_CRC_IRQ)
204 			data->error = -EILSEQ;
205 		else if (stat & (BM_SSP_CTRL1_FIFO_UNDERRUN_IRQ |
206 				 BM_SSP_CTRL1_FIFO_OVERRUN_IRQ))
207 			data->error = -EIO;
208 	}
209 
210 	return IRQ_HANDLED;
211 }
212 
213 static struct dma_async_tx_descriptor *mxs_mmc_prep_dma(
214 	struct mxs_mmc_host *host, unsigned long flags)
215 {
216 	struct mxs_ssp *ssp = &host->ssp;
217 	struct dma_async_tx_descriptor *desc;
218 	struct mmc_data *data = host->data;
219 	struct scatterlist * sgl;
220 	unsigned int sg_len;
221 
222 	if (data) {
223 		/* data */
224 		dma_map_sg(mmc_dev(host->mmc), data->sg,
225 			   data->sg_len, ssp->dma_dir);
226 		sgl = data->sg;
227 		sg_len = data->sg_len;
228 	} else {
229 		/* pio */
230 		sgl = (struct scatterlist *) ssp->ssp_pio_words;
231 		sg_len = SSP_PIO_NUM;
232 	}
233 
234 	desc = dmaengine_prep_slave_sg(ssp->dmach,
235 				sgl, sg_len, ssp->slave_dirn, flags);
236 	if (desc) {
237 		desc->callback = mxs_mmc_dma_irq_callback;
238 		desc->callback_param = host;
239 	} else {
240 		if (data)
241 			dma_unmap_sg(mmc_dev(host->mmc), data->sg,
242 				     data->sg_len, ssp->dma_dir);
243 	}
244 
245 	return desc;
246 }
247 
248 static void mxs_mmc_bc(struct mxs_mmc_host *host)
249 {
250 	struct mxs_ssp *ssp = &host->ssp;
251 	struct mmc_command *cmd = host->cmd;
252 	struct dma_async_tx_descriptor *desc;
253 	u32 ctrl0, cmd0, cmd1;
254 
255 	ctrl0 = BM_SSP_CTRL0_ENABLE | BM_SSP_CTRL0_IGNORE_CRC;
256 	cmd0 = BF_SSP(cmd->opcode, CMD0_CMD) | BM_SSP_CMD0_APPEND_8CYC;
257 	cmd1 = cmd->arg;
258 
259 	if (host->sdio_irq_en) {
260 		ctrl0 |= BM_SSP_CTRL0_SDIO_IRQ_CHECK;
261 		cmd0 |= BM_SSP_CMD0_CONT_CLKING_EN | BM_SSP_CMD0_SLOW_CLKING_EN;
262 	}
263 
264 	ssp->ssp_pio_words[0] = ctrl0;
265 	ssp->ssp_pio_words[1] = cmd0;
266 	ssp->ssp_pio_words[2] = cmd1;
267 	ssp->dma_dir = DMA_NONE;
268 	ssp->slave_dirn = DMA_TRANS_NONE;
269 	desc = mxs_mmc_prep_dma(host, MXS_DMA_CTRL_WAIT4END);
270 	if (!desc)
271 		goto out;
272 
273 	dmaengine_submit(desc);
274 	dma_async_issue_pending(ssp->dmach);
275 	return;
276 
277 out:
278 	dev_warn(mmc_dev(host->mmc),
279 		 "%s: failed to prep dma\n", __func__);
280 }
281 
282 static void mxs_mmc_ac(struct mxs_mmc_host *host)
283 {
284 	struct mxs_ssp *ssp = &host->ssp;
285 	struct mmc_command *cmd = host->cmd;
286 	struct dma_async_tx_descriptor *desc;
287 	u32 ignore_crc, get_resp, long_resp;
288 	u32 ctrl0, cmd0, cmd1;
289 
290 	ignore_crc = (mmc_resp_type(cmd) & MMC_RSP_CRC) ?
291 			0 : BM_SSP_CTRL0_IGNORE_CRC;
292 	get_resp = (mmc_resp_type(cmd) & MMC_RSP_PRESENT) ?
293 			BM_SSP_CTRL0_GET_RESP : 0;
294 	long_resp = (mmc_resp_type(cmd) & MMC_RSP_136) ?
295 			BM_SSP_CTRL0_LONG_RESP : 0;
296 
297 	ctrl0 = BM_SSP_CTRL0_ENABLE | ignore_crc | get_resp | long_resp;
298 	cmd0 = BF_SSP(cmd->opcode, CMD0_CMD);
299 	cmd1 = cmd->arg;
300 
301 	if (cmd->opcode == MMC_STOP_TRANSMISSION)
302 		cmd0 |= BM_SSP_CMD0_APPEND_8CYC;
303 
304 	if (host->sdio_irq_en) {
305 		ctrl0 |= BM_SSP_CTRL0_SDIO_IRQ_CHECK;
306 		cmd0 |= BM_SSP_CMD0_CONT_CLKING_EN | BM_SSP_CMD0_SLOW_CLKING_EN;
307 	}
308 
309 	ssp->ssp_pio_words[0] = ctrl0;
310 	ssp->ssp_pio_words[1] = cmd0;
311 	ssp->ssp_pio_words[2] = cmd1;
312 	ssp->dma_dir = DMA_NONE;
313 	ssp->slave_dirn = DMA_TRANS_NONE;
314 	desc = mxs_mmc_prep_dma(host, MXS_DMA_CTRL_WAIT4END);
315 	if (!desc)
316 		goto out;
317 
318 	dmaengine_submit(desc);
319 	dma_async_issue_pending(ssp->dmach);
320 	return;
321 
322 out:
323 	dev_warn(mmc_dev(host->mmc),
324 		 "%s: failed to prep dma\n", __func__);
325 }
326 
327 static unsigned short mxs_ns_to_ssp_ticks(unsigned clock_rate, unsigned ns)
328 {
329 	const unsigned int ssp_timeout_mul = 4096;
330 	/*
331 	 * Calculate ticks in ms since ns are large numbers
332 	 * and might overflow
333 	 */
334 	const unsigned int clock_per_ms = clock_rate / 1000;
335 	const unsigned int ms = ns / 1000;
336 	const unsigned int ticks = ms * clock_per_ms;
337 	const unsigned int ssp_ticks = ticks / ssp_timeout_mul;
338 
339 	WARN_ON(ssp_ticks == 0);
340 	return ssp_ticks;
341 }
342 
343 static void mxs_mmc_adtc(struct mxs_mmc_host *host)
344 {
345 	struct mmc_command *cmd = host->cmd;
346 	struct mmc_data *data = cmd->data;
347 	struct dma_async_tx_descriptor *desc;
348 	struct scatterlist *sgl = data->sg, *sg;
349 	unsigned int sg_len = data->sg_len;
350 	unsigned int i;
351 
352 	unsigned short dma_data_dir, timeout;
353 	enum dma_transfer_direction slave_dirn;
354 	unsigned int data_size = 0, log2_blksz;
355 	unsigned int blocks = data->blocks;
356 
357 	struct mxs_ssp *ssp = &host->ssp;
358 
359 	u32 ignore_crc, get_resp, long_resp, read;
360 	u32 ctrl0, cmd0, cmd1, val;
361 
362 	ignore_crc = (mmc_resp_type(cmd) & MMC_RSP_CRC) ?
363 			0 : BM_SSP_CTRL0_IGNORE_CRC;
364 	get_resp = (mmc_resp_type(cmd) & MMC_RSP_PRESENT) ?
365 			BM_SSP_CTRL0_GET_RESP : 0;
366 	long_resp = (mmc_resp_type(cmd) & MMC_RSP_136) ?
367 			BM_SSP_CTRL0_LONG_RESP : 0;
368 
369 	if (data->flags & MMC_DATA_WRITE) {
370 		dma_data_dir = DMA_TO_DEVICE;
371 		slave_dirn = DMA_MEM_TO_DEV;
372 		read = 0;
373 	} else {
374 		dma_data_dir = DMA_FROM_DEVICE;
375 		slave_dirn = DMA_DEV_TO_MEM;
376 		read = BM_SSP_CTRL0_READ;
377 	}
378 
379 	ctrl0 = BF_SSP(host->bus_width, CTRL0_BUS_WIDTH) |
380 		ignore_crc | get_resp | long_resp |
381 		BM_SSP_CTRL0_DATA_XFER | read |
382 		BM_SSP_CTRL0_WAIT_FOR_IRQ |
383 		BM_SSP_CTRL0_ENABLE;
384 
385 	cmd0 = BF_SSP(cmd->opcode, CMD0_CMD);
386 
387 	/* get logarithm to base 2 of block size for setting register */
388 	log2_blksz = ilog2(data->blksz);
389 
390 	/*
391 	 * take special care of the case that data size from data->sg
392 	 * is not equal to blocks x blksz
393 	 */
394 	for_each_sg(sgl, sg, sg_len, i)
395 		data_size += sg->length;
396 
397 	if (data_size != data->blocks * data->blksz)
398 		blocks = 1;
399 
400 	/* xfer count, block size and count need to be set differently */
401 	if (ssp_is_old(ssp)) {
402 		ctrl0 |= BF_SSP(data_size, CTRL0_XFER_COUNT);
403 		cmd0 |= BF_SSP(log2_blksz, CMD0_BLOCK_SIZE) |
404 			BF_SSP(blocks - 1, CMD0_BLOCK_COUNT);
405 	} else {
406 		writel(data_size, ssp->base + HW_SSP_XFER_SIZE);
407 		writel(BF_SSP(log2_blksz, BLOCK_SIZE_BLOCK_SIZE) |
408 		       BF_SSP(blocks - 1, BLOCK_SIZE_BLOCK_COUNT),
409 		       ssp->base + HW_SSP_BLOCK_SIZE);
410 	}
411 
412 	if (cmd->opcode == SD_IO_RW_EXTENDED)
413 		cmd0 |= BM_SSP_CMD0_APPEND_8CYC;
414 
415 	cmd1 = cmd->arg;
416 
417 	if (host->sdio_irq_en) {
418 		ctrl0 |= BM_SSP_CTRL0_SDIO_IRQ_CHECK;
419 		cmd0 |= BM_SSP_CMD0_CONT_CLKING_EN | BM_SSP_CMD0_SLOW_CLKING_EN;
420 	}
421 
422 	/* set the timeout count */
423 	timeout = mxs_ns_to_ssp_ticks(ssp->clk_rate, data->timeout_ns);
424 	val = readl(ssp->base + HW_SSP_TIMING(ssp));
425 	val &= ~(BM_SSP_TIMING_TIMEOUT);
426 	val |= BF_SSP(timeout, TIMING_TIMEOUT);
427 	writel(val, ssp->base + HW_SSP_TIMING(ssp));
428 
429 	/* pio */
430 	ssp->ssp_pio_words[0] = ctrl0;
431 	ssp->ssp_pio_words[1] = cmd0;
432 	ssp->ssp_pio_words[2] = cmd1;
433 	ssp->dma_dir = DMA_NONE;
434 	ssp->slave_dirn = DMA_TRANS_NONE;
435 	desc = mxs_mmc_prep_dma(host, 0);
436 	if (!desc)
437 		goto out;
438 
439 	/* append data sg */
440 	WARN_ON(host->data != NULL);
441 	host->data = data;
442 	ssp->dma_dir = dma_data_dir;
443 	ssp->slave_dirn = slave_dirn;
444 	desc = mxs_mmc_prep_dma(host, DMA_PREP_INTERRUPT | MXS_DMA_CTRL_WAIT4END);
445 	if (!desc)
446 		goto out;
447 
448 	dmaengine_submit(desc);
449 	dma_async_issue_pending(ssp->dmach);
450 	return;
451 out:
452 	dev_warn(mmc_dev(host->mmc),
453 		 "%s: failed to prep dma\n", __func__);
454 }
455 
456 static void mxs_mmc_start_cmd(struct mxs_mmc_host *host,
457 			      struct mmc_command *cmd)
458 {
459 	host->cmd = cmd;
460 
461 	switch (mmc_cmd_type(cmd)) {
462 	case MMC_CMD_BC:
463 		mxs_mmc_bc(host);
464 		break;
465 	case MMC_CMD_BCR:
466 		mxs_mmc_ac(host);
467 		break;
468 	case MMC_CMD_AC:
469 		mxs_mmc_ac(host);
470 		break;
471 	case MMC_CMD_ADTC:
472 		mxs_mmc_adtc(host);
473 		break;
474 	default:
475 		dev_warn(mmc_dev(host->mmc),
476 			 "%s: unknown MMC command\n", __func__);
477 		break;
478 	}
479 }
480 
481 static void mxs_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
482 {
483 	struct mxs_mmc_host *host = mmc_priv(mmc);
484 
485 	WARN_ON(host->mrq != NULL);
486 	host->mrq = mrq;
487 
488 	if (mrq->sbc)
489 		mxs_mmc_start_cmd(host, mrq->sbc);
490 	else
491 		mxs_mmc_start_cmd(host, mrq->cmd);
492 }
493 
494 static void mxs_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
495 {
496 	struct mxs_mmc_host *host = mmc_priv(mmc);
497 
498 	if (ios->bus_width == MMC_BUS_WIDTH_8)
499 		host->bus_width = 2;
500 	else if (ios->bus_width == MMC_BUS_WIDTH_4)
501 		host->bus_width = 1;
502 	else
503 		host->bus_width = 0;
504 
505 	if (ios->clock)
506 		mxs_ssp_set_clk_rate(&host->ssp, ios->clock);
507 }
508 
509 static void mxs_mmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
510 {
511 	struct mxs_mmc_host *host = mmc_priv(mmc);
512 	struct mxs_ssp *ssp = &host->ssp;
513 	unsigned long flags;
514 
515 	spin_lock_irqsave(&host->lock, flags);
516 
517 	host->sdio_irq_en = enable;
518 
519 	if (enable) {
520 		writel(BM_SSP_CTRL0_SDIO_IRQ_CHECK,
521 		       ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET);
522 		writel(BM_SSP_CTRL1_SDIO_IRQ_EN,
523 		       ssp->base + HW_SSP_CTRL1(ssp) + STMP_OFFSET_REG_SET);
524 	} else {
525 		writel(BM_SSP_CTRL0_SDIO_IRQ_CHECK,
526 		       ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR);
527 		writel(BM_SSP_CTRL1_SDIO_IRQ_EN,
528 		       ssp->base + HW_SSP_CTRL1(ssp) + STMP_OFFSET_REG_CLR);
529 	}
530 
531 	spin_unlock_irqrestore(&host->lock, flags);
532 
533 	if (enable && readl(ssp->base + HW_SSP_STATUS(ssp)) &
534 			BM_SSP_STATUS_SDIO_IRQ)
535 		mmc_signal_sdio_irq(host->mmc);
536 
537 }
538 
539 static const struct mmc_host_ops mxs_mmc_ops = {
540 	.request = mxs_mmc_request,
541 	.get_ro = mmc_gpio_get_ro,
542 	.get_cd = mxs_mmc_get_cd,
543 	.set_ios = mxs_mmc_set_ios,
544 	.enable_sdio_irq = mxs_mmc_enable_sdio_irq,
545 };
546 
547 static const struct of_device_id mxs_mmc_dt_ids[] = {
548 	{ .compatible = "fsl,imx23-mmc", .data = (void *) IMX23_SSP, },
549 	{ .compatible = "fsl,imx28-mmc", .data = (void *) IMX28_SSP, },
550 	{ /* sentinel */ }
551 };
552 MODULE_DEVICE_TABLE(of, mxs_mmc_dt_ids);
553 
554 static void mxs_mmc_regulator_disable(void *regulator)
555 {
556 	regulator_disable(regulator);
557 }
558 
559 static int mxs_mmc_probe(struct platform_device *pdev)
560 {
561 	struct device_node *np = pdev->dev.of_node;
562 	struct mxs_mmc_host *host;
563 	struct mmc_host *mmc;
564 	int ret = 0, irq_err;
565 	struct regulator *reg_vmmc;
566 	struct mxs_ssp *ssp;
567 
568 	irq_err = platform_get_irq(pdev, 0);
569 	if (irq_err < 0)
570 		return irq_err;
571 
572 	mmc = mmc_alloc_host(sizeof(struct mxs_mmc_host), &pdev->dev);
573 	if (!mmc)
574 		return -ENOMEM;
575 
576 	host = mmc_priv(mmc);
577 	ssp = &host->ssp;
578 	ssp->dev = &pdev->dev;
579 	ssp->base = devm_platform_ioremap_resource(pdev, 0);
580 	if (IS_ERR(ssp->base)) {
581 		ret = PTR_ERR(ssp->base);
582 		goto out_mmc_free;
583 	}
584 
585 	ssp->devid = (enum mxs_ssp_id)of_device_get_match_data(&pdev->dev);
586 
587 	host->mmc = mmc;
588 	host->sdio_irq_en = 0;
589 
590 	reg_vmmc = devm_regulator_get(&pdev->dev, "vmmc");
591 	if (!IS_ERR(reg_vmmc)) {
592 		ret = regulator_enable(reg_vmmc);
593 		if (ret) {
594 			dev_err(&pdev->dev,
595 				"Failed to enable vmmc regulator: %d\n", ret);
596 			goto out_mmc_free;
597 		}
598 
599 		ret = devm_add_action_or_reset(&pdev->dev, mxs_mmc_regulator_disable,
600 					       reg_vmmc);
601 		if (ret)
602 			goto out_mmc_free;
603 	}
604 
605 	ssp->clk = devm_clk_get(&pdev->dev, NULL);
606 	if (IS_ERR(ssp->clk)) {
607 		ret = PTR_ERR(ssp->clk);
608 		goto out_mmc_free;
609 	}
610 	ret = clk_prepare_enable(ssp->clk);
611 	if (ret)
612 		goto out_mmc_free;
613 
614 	ret = mxs_mmc_reset(host);
615 	if (ret) {
616 		dev_err(&pdev->dev, "Failed to reset mmc: %d\n", ret);
617 		goto out_clk_disable;
618 	}
619 
620 	ssp->dmach = dma_request_chan(&pdev->dev, "rx-tx");
621 	if (IS_ERR(ssp->dmach)) {
622 		dev_err(mmc_dev(host->mmc),
623 			"%s: failed to request dma\n", __func__);
624 		ret = PTR_ERR(ssp->dmach);
625 		goto out_clk_disable;
626 	}
627 
628 	/* set mmc core parameters */
629 	mmc->ops = &mxs_mmc_ops;
630 	mmc->caps = MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED |
631 		    MMC_CAP_SDIO_IRQ | MMC_CAP_NEEDS_POLL | MMC_CAP_CMD23;
632 
633 	host->broken_cd = of_property_read_bool(np, "broken-cd");
634 
635 	mmc->f_min = 400000;
636 	mmc->f_max = 288000000;
637 
638 	ret = mmc_of_parse(mmc);
639 	if (ret)
640 		goto out_free_dma;
641 
642 	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
643 
644 	mmc->max_segs = 52;
645 	mmc->max_blk_size = 1 << 0xf;
646 	mmc->max_blk_count = (ssp_is_old(ssp)) ? 0xff : 0xffffff;
647 	mmc->max_req_size = (ssp_is_old(ssp)) ? 0xffff : 0xffffffff;
648 	mmc->max_seg_size = dma_get_max_seg_size(ssp->dmach->device->dev);
649 
650 	platform_set_drvdata(pdev, mmc);
651 
652 	spin_lock_init(&host->lock);
653 
654 	ret = devm_request_irq(&pdev->dev, irq_err, mxs_mmc_irq_handler, 0,
655 			       dev_name(&pdev->dev), host);
656 	if (ret)
657 		goto out_free_dma;
658 
659 	ret = mmc_add_host(mmc);
660 	if (ret)
661 		goto out_free_dma;
662 
663 	dev_info(mmc_dev(host->mmc), "initialized\n");
664 
665 	return 0;
666 
667 out_free_dma:
668 	dma_release_channel(ssp->dmach);
669 out_clk_disable:
670 	clk_disable_unprepare(ssp->clk);
671 out_mmc_free:
672 	mmc_free_host(mmc);
673 	return ret;
674 }
675 
676 static void mxs_mmc_remove(struct platform_device *pdev)
677 {
678 	struct mmc_host *mmc = platform_get_drvdata(pdev);
679 	struct mxs_mmc_host *host = mmc_priv(mmc);
680 	struct mxs_ssp *ssp = &host->ssp;
681 
682 	mmc_remove_host(mmc);
683 
684 	if (ssp->dmach)
685 		dma_release_channel(ssp->dmach);
686 
687 	clk_disable_unprepare(ssp->clk);
688 
689 	mmc_free_host(mmc);
690 }
691 
692 #ifdef CONFIG_PM_SLEEP
693 static int mxs_mmc_suspend(struct device *dev)
694 {
695 	struct mmc_host *mmc = dev_get_drvdata(dev);
696 	struct mxs_mmc_host *host = mmc_priv(mmc);
697 	struct mxs_ssp *ssp = &host->ssp;
698 
699 	clk_disable_unprepare(ssp->clk);
700 	return 0;
701 }
702 
703 static int mxs_mmc_resume(struct device *dev)
704 {
705 	struct mmc_host *mmc = dev_get_drvdata(dev);
706 	struct mxs_mmc_host *host = mmc_priv(mmc);
707 	struct mxs_ssp *ssp = &host->ssp;
708 
709 	return clk_prepare_enable(ssp->clk);
710 }
711 #endif
712 
713 static SIMPLE_DEV_PM_OPS(mxs_mmc_pm_ops, mxs_mmc_suspend, mxs_mmc_resume);
714 
715 static struct platform_driver mxs_mmc_driver = {
716 	.probe		= mxs_mmc_probe,
717 	.remove_new	= mxs_mmc_remove,
718 	.driver		= {
719 		.name	= DRIVER_NAME,
720 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
721 		.pm	= &mxs_mmc_pm_ops,
722 		.of_match_table = mxs_mmc_dt_ids,
723 	},
724 };
725 
726 module_platform_driver(mxs_mmc_driver);
727 
728 MODULE_DESCRIPTION("FREESCALE MXS MMC peripheral");
729 MODULE_AUTHOR("Freescale Semiconductor");
730 MODULE_LICENSE("GPL");
731 MODULE_ALIAS("platform:" DRIVER_NAME);
732