xref: /openbmc/linux/drivers/mmc/host/mxcmmc.c (revision b04b4f78)
1 /*
2  *  linux/drivers/mmc/host/mxcmmc.c - Freescale i.MX MMCI driver
3  *
4  *  This is a driver for the SDHC controller found in Freescale MX2/MX3
5  *  SoCs. It is basically the same hardware as found on MX1 (imxmmc.c).
6  *  Unlike the hardware found on MX1, this hardware just works and does
7  *  not need all the quirks found in imxmmc.c, hence the seperate driver.
8  *
9  *  Copyright (C) 2008 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
10  *  Copyright (C) 2006 Pavel Pisa, PiKRON <ppisa@pikron.com>
11  *
12  *  derived from pxamci.c by Russell King
13  *
14  * This program is free software; you can redistribute it and/or modify
15  * it under the terms of the GNU General Public License version 2 as
16  * published by the Free Software Foundation.
17  *
18  */
19 
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/ioport.h>
23 #include <linux/platform_device.h>
24 #include <linux/interrupt.h>
25 #include <linux/irq.h>
26 #include <linux/blkdev.h>
27 #include <linux/dma-mapping.h>
28 #include <linux/mmc/host.h>
29 #include <linux/mmc/card.h>
30 #include <linux/delay.h>
31 #include <linux/clk.h>
32 #include <linux/io.h>
33 #include <linux/gpio.h>
34 
35 #include <asm/dma.h>
36 #include <asm/irq.h>
37 #include <asm/sizes.h>
38 #include <mach/mmc.h>
39 
40 #ifdef CONFIG_ARCH_MX2
41 #include <mach/dma-mx1-mx2.h>
42 #define HAS_DMA
43 #endif
44 
45 #define DRIVER_NAME "mxc-mmc"
46 
47 #define MMC_REG_STR_STP_CLK		0x00
48 #define MMC_REG_STATUS			0x04
49 #define MMC_REG_CLK_RATE		0x08
50 #define MMC_REG_CMD_DAT_CONT		0x0C
51 #define MMC_REG_RES_TO			0x10
52 #define MMC_REG_READ_TO			0x14
53 #define MMC_REG_BLK_LEN			0x18
54 #define MMC_REG_NOB			0x1C
55 #define MMC_REG_REV_NO			0x20
56 #define MMC_REG_INT_CNTR		0x24
57 #define MMC_REG_CMD			0x28
58 #define MMC_REG_ARG			0x2C
59 #define MMC_REG_RES_FIFO		0x34
60 #define MMC_REG_BUFFER_ACCESS		0x38
61 
62 #define STR_STP_CLK_RESET               (1 << 3)
63 #define STR_STP_CLK_START_CLK           (1 << 1)
64 #define STR_STP_CLK_STOP_CLK            (1 << 0)
65 
66 #define STATUS_CARD_INSERTION		(1 << 31)
67 #define STATUS_CARD_REMOVAL		(1 << 30)
68 #define STATUS_YBUF_EMPTY		(1 << 29)
69 #define STATUS_XBUF_EMPTY		(1 << 28)
70 #define STATUS_YBUF_FULL		(1 << 27)
71 #define STATUS_XBUF_FULL		(1 << 26)
72 #define STATUS_BUF_UND_RUN		(1 << 25)
73 #define STATUS_BUF_OVFL			(1 << 24)
74 #define STATUS_SDIO_INT_ACTIVE		(1 << 14)
75 #define STATUS_END_CMD_RESP		(1 << 13)
76 #define STATUS_WRITE_OP_DONE		(1 << 12)
77 #define STATUS_DATA_TRANS_DONE		(1 << 11)
78 #define STATUS_READ_OP_DONE		(1 << 11)
79 #define STATUS_WR_CRC_ERROR_CODE_MASK	(3 << 10)
80 #define STATUS_CARD_BUS_CLK_RUN		(1 << 8)
81 #define STATUS_BUF_READ_RDY		(1 << 7)
82 #define STATUS_BUF_WRITE_RDY		(1 << 6)
83 #define STATUS_RESP_CRC_ERR		(1 << 5)
84 #define STATUS_CRC_READ_ERR		(1 << 3)
85 #define STATUS_CRC_WRITE_ERR		(1 << 2)
86 #define STATUS_TIME_OUT_RESP		(1 << 1)
87 #define STATUS_TIME_OUT_READ		(1 << 0)
88 #define STATUS_ERR_MASK			0x2f
89 
90 #define CMD_DAT_CONT_CMD_RESP_LONG_OFF	(1 << 12)
91 #define CMD_DAT_CONT_STOP_READWAIT	(1 << 11)
92 #define CMD_DAT_CONT_START_READWAIT	(1 << 10)
93 #define CMD_DAT_CONT_BUS_WIDTH_4	(2 << 8)
94 #define CMD_DAT_CONT_INIT		(1 << 7)
95 #define CMD_DAT_CONT_WRITE		(1 << 4)
96 #define CMD_DAT_CONT_DATA_ENABLE	(1 << 3)
97 #define CMD_DAT_CONT_RESPONSE_48BIT_CRC	(1 << 0)
98 #define CMD_DAT_CONT_RESPONSE_136BIT	(2 << 0)
99 #define CMD_DAT_CONT_RESPONSE_48BIT	(3 << 0)
100 
101 #define INT_SDIO_INT_WKP_EN		(1 << 18)
102 #define INT_CARD_INSERTION_WKP_EN	(1 << 17)
103 #define INT_CARD_REMOVAL_WKP_EN		(1 << 16)
104 #define INT_CARD_INSERTION_EN		(1 << 15)
105 #define INT_CARD_REMOVAL_EN		(1 << 14)
106 #define INT_SDIO_IRQ_EN			(1 << 13)
107 #define INT_DAT0_EN			(1 << 12)
108 #define INT_BUF_READ_EN			(1 << 4)
109 #define INT_BUF_WRITE_EN		(1 << 3)
110 #define INT_END_CMD_RES_EN		(1 << 2)
111 #define INT_WRITE_OP_DONE_EN		(1 << 1)
112 #define INT_READ_OP_EN			(1 << 0)
113 
114 struct mxcmci_host {
115 	struct mmc_host		*mmc;
116 	struct resource		*res;
117 	void __iomem		*base;
118 	int			irq;
119 	int			detect_irq;
120 	int			dma;
121 	int			do_dma;
122 	unsigned int		power_mode;
123 	struct imxmmc_platform_data *pdata;
124 
125 	struct mmc_request	*req;
126 	struct mmc_command	*cmd;
127 	struct mmc_data		*data;
128 
129 	unsigned int		dma_nents;
130 	unsigned int		datasize;
131 	unsigned int		dma_dir;
132 
133 	u16			rev_no;
134 	unsigned int		cmdat;
135 
136 	struct clk		*clk;
137 
138 	int			clock;
139 
140 	struct work_struct	datawork;
141 };
142 
143 static inline int mxcmci_use_dma(struct mxcmci_host *host)
144 {
145 	return host->do_dma;
146 }
147 
148 static void mxcmci_softreset(struct mxcmci_host *host)
149 {
150 	int i;
151 
152 	/* reset sequence */
153 	writew(STR_STP_CLK_RESET, host->base + MMC_REG_STR_STP_CLK);
154 	writew(STR_STP_CLK_RESET | STR_STP_CLK_START_CLK,
155 			host->base + MMC_REG_STR_STP_CLK);
156 
157 	for (i = 0; i < 8; i++)
158 		writew(STR_STP_CLK_START_CLK, host->base + MMC_REG_STR_STP_CLK);
159 
160 	writew(0xff, host->base + MMC_REG_RES_TO);
161 }
162 
163 static void mxcmci_setup_data(struct mxcmci_host *host, struct mmc_data *data)
164 {
165 	unsigned int nob = data->blocks;
166 	unsigned int blksz = data->blksz;
167 	unsigned int datasize = nob * blksz;
168 #ifdef HAS_DMA
169 	struct scatterlist *sg;
170 	int i;
171 #endif
172 	if (data->flags & MMC_DATA_STREAM)
173 		nob = 0xffff;
174 
175 	host->data = data;
176 	data->bytes_xfered = 0;
177 
178 	writew(nob, host->base + MMC_REG_NOB);
179 	writew(blksz, host->base + MMC_REG_BLK_LEN);
180 	host->datasize = datasize;
181 
182 #ifdef HAS_DMA
183 	for_each_sg(data->sg, sg, data->sg_len, i) {
184 		if (sg->offset & 3 || sg->length & 3) {
185 			host->do_dma = 0;
186 			return;
187 		}
188 	}
189 
190 	if (data->flags & MMC_DATA_READ) {
191 		host->dma_dir = DMA_FROM_DEVICE;
192 		host->dma_nents = dma_map_sg(mmc_dev(host->mmc), data->sg,
193 					     data->sg_len,  host->dma_dir);
194 
195 		imx_dma_setup_sg(host->dma, data->sg, host->dma_nents, datasize,
196 				 host->res->start + MMC_REG_BUFFER_ACCESS,
197 				 DMA_MODE_READ);
198 	} else {
199 		host->dma_dir = DMA_TO_DEVICE;
200 		host->dma_nents = dma_map_sg(mmc_dev(host->mmc), data->sg,
201 					     data->sg_len,  host->dma_dir);
202 
203 		imx_dma_setup_sg(host->dma, data->sg, host->dma_nents, datasize,
204 				 host->res->start + MMC_REG_BUFFER_ACCESS,
205 				 DMA_MODE_WRITE);
206 	}
207 
208 	wmb();
209 
210 	imx_dma_enable(host->dma);
211 #endif /* HAS_DMA */
212 }
213 
214 static int mxcmci_start_cmd(struct mxcmci_host *host, struct mmc_command *cmd,
215 		unsigned int cmdat)
216 {
217 	WARN_ON(host->cmd != NULL);
218 	host->cmd = cmd;
219 
220 	switch (mmc_resp_type(cmd)) {
221 	case MMC_RSP_R1: /* short CRC, OPCODE */
222 	case MMC_RSP_R1B:/* short CRC, OPCODE, BUSY */
223 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT_CRC;
224 		break;
225 	case MMC_RSP_R2: /* long 136 bit + CRC */
226 		cmdat |= CMD_DAT_CONT_RESPONSE_136BIT;
227 		break;
228 	case MMC_RSP_R3: /* short */
229 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT;
230 		break;
231 	case MMC_RSP_NONE:
232 		break;
233 	default:
234 		dev_err(mmc_dev(host->mmc), "unhandled response type 0x%x\n",
235 				mmc_resp_type(cmd));
236 		cmd->error = -EINVAL;
237 		return -EINVAL;
238 	}
239 
240 	if (mxcmci_use_dma(host))
241 		writel(INT_READ_OP_EN | INT_WRITE_OP_DONE_EN |
242 				INT_END_CMD_RES_EN,
243 				host->base + MMC_REG_INT_CNTR);
244 	else
245 		writel(INT_END_CMD_RES_EN, host->base + MMC_REG_INT_CNTR);
246 
247 	writew(cmd->opcode, host->base + MMC_REG_CMD);
248 	writel(cmd->arg, host->base + MMC_REG_ARG);
249 	writew(cmdat, host->base + MMC_REG_CMD_DAT_CONT);
250 
251 	return 0;
252 }
253 
254 static void mxcmci_finish_request(struct mxcmci_host *host,
255 		struct mmc_request *req)
256 {
257 	writel(0, host->base + MMC_REG_INT_CNTR);
258 
259 	host->req = NULL;
260 	host->cmd = NULL;
261 	host->data = NULL;
262 
263 	mmc_request_done(host->mmc, req);
264 }
265 
266 static int mxcmci_finish_data(struct mxcmci_host *host, unsigned int stat)
267 {
268 	struct mmc_data *data = host->data;
269 	int data_error;
270 
271 #ifdef HAS_DMA
272 	if (mxcmci_use_dma(host)) {
273 		imx_dma_disable(host->dma);
274 		dma_unmap_sg(mmc_dev(host->mmc), data->sg, host->dma_nents,
275 				host->dma_dir);
276 	}
277 #endif
278 
279 	if (stat & STATUS_ERR_MASK) {
280 		dev_dbg(mmc_dev(host->mmc), "request failed. status: 0x%08x\n",
281 				stat);
282 		if (stat & STATUS_CRC_READ_ERR) {
283 			data->error = -EILSEQ;
284 		} else if (stat & STATUS_CRC_WRITE_ERR) {
285 			u32 err_code = (stat >> 9) & 0x3;
286 			if (err_code == 2) /* No CRC response */
287 				data->error = -ETIMEDOUT;
288 			else
289 				data->error = -EILSEQ;
290 		} else if (stat & STATUS_TIME_OUT_READ) {
291 			data->error = -ETIMEDOUT;
292 		} else {
293 			data->error = -EIO;
294 		}
295 	} else {
296 		data->bytes_xfered = host->datasize;
297 	}
298 
299 	data_error = data->error;
300 
301 	host->data = NULL;
302 
303 	return data_error;
304 }
305 
306 static void mxcmci_read_response(struct mxcmci_host *host, unsigned int stat)
307 {
308 	struct mmc_command *cmd = host->cmd;
309 	int i;
310 	u32 a, b, c;
311 
312 	if (!cmd)
313 		return;
314 
315 	if (stat & STATUS_TIME_OUT_RESP) {
316 		dev_dbg(mmc_dev(host->mmc), "CMD TIMEOUT\n");
317 		cmd->error = -ETIMEDOUT;
318 	} else if (stat & STATUS_RESP_CRC_ERR && cmd->flags & MMC_RSP_CRC) {
319 		dev_dbg(mmc_dev(host->mmc), "cmd crc error\n");
320 		cmd->error = -EILSEQ;
321 	}
322 
323 	if (cmd->flags & MMC_RSP_PRESENT) {
324 		if (cmd->flags & MMC_RSP_136) {
325 			for (i = 0; i < 4; i++) {
326 				a = readw(host->base + MMC_REG_RES_FIFO);
327 				b = readw(host->base + MMC_REG_RES_FIFO);
328 				cmd->resp[i] = a << 16 | b;
329 			}
330 		} else {
331 			a = readw(host->base + MMC_REG_RES_FIFO);
332 			b = readw(host->base + MMC_REG_RES_FIFO);
333 			c = readw(host->base + MMC_REG_RES_FIFO);
334 			cmd->resp[0] = a << 24 | b << 8 | c >> 8;
335 		}
336 	}
337 }
338 
339 static int mxcmci_poll_status(struct mxcmci_host *host, u32 mask)
340 {
341 	u32 stat;
342 	unsigned long timeout = jiffies + HZ;
343 
344 	do {
345 		stat = readl(host->base + MMC_REG_STATUS);
346 		if (stat & STATUS_ERR_MASK)
347 			return stat;
348 		if (time_after(jiffies, timeout))
349 			return STATUS_TIME_OUT_READ;
350 		if (stat & mask)
351 			return 0;
352 		cpu_relax();
353 	} while (1);
354 }
355 
356 static int mxcmci_pull(struct mxcmci_host *host, void *_buf, int bytes)
357 {
358 	unsigned int stat;
359 	u32 *buf = _buf;
360 
361 	while (bytes > 3) {
362 		stat = mxcmci_poll_status(host,
363 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
364 		if (stat)
365 			return stat;
366 		*buf++ = readl(host->base + MMC_REG_BUFFER_ACCESS);
367 		bytes -= 4;
368 	}
369 
370 	if (bytes) {
371 		u8 *b = (u8 *)buf;
372 		u32 tmp;
373 
374 		stat = mxcmci_poll_status(host,
375 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
376 		if (stat)
377 			return stat;
378 		tmp = readl(host->base + MMC_REG_BUFFER_ACCESS);
379 		memcpy(b, &tmp, bytes);
380 	}
381 
382 	return 0;
383 }
384 
385 static int mxcmci_push(struct mxcmci_host *host, void *_buf, int bytes)
386 {
387 	unsigned int stat;
388 	u32 *buf = _buf;
389 
390 	while (bytes > 3) {
391 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
392 		if (stat)
393 			return stat;
394 		writel(*buf++, host->base + MMC_REG_BUFFER_ACCESS);
395 		bytes -= 4;
396 	}
397 
398 	if (bytes) {
399 		u8 *b = (u8 *)buf;
400 		u32 tmp;
401 
402 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
403 		if (stat)
404 			return stat;
405 
406 		memcpy(&tmp, b, bytes);
407 		writel(tmp, host->base + MMC_REG_BUFFER_ACCESS);
408 	}
409 
410 	stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
411 	if (stat)
412 		return stat;
413 
414 	return 0;
415 }
416 
417 static int mxcmci_transfer_data(struct mxcmci_host *host)
418 {
419 	struct mmc_data *data = host->req->data;
420 	struct scatterlist *sg;
421 	int stat, i;
422 
423 	host->datasize = 0;
424 
425 	host->data = data;
426 	host->datasize = 0;
427 
428 	if (data->flags & MMC_DATA_READ) {
429 		for_each_sg(data->sg, sg, data->sg_len, i) {
430 			stat = mxcmci_pull(host, sg_virt(sg), sg->length);
431 			if (stat)
432 				return stat;
433 			host->datasize += sg->length;
434 		}
435 	} else {
436 		for_each_sg(data->sg, sg, data->sg_len, i) {
437 			stat = mxcmci_push(host, sg_virt(sg), sg->length);
438 			if (stat)
439 				return stat;
440 			host->datasize += sg->length;
441 		}
442 		stat = mxcmci_poll_status(host, STATUS_WRITE_OP_DONE);
443 		if (stat)
444 			return stat;
445 	}
446 	return 0;
447 }
448 
449 static void mxcmci_datawork(struct work_struct *work)
450 {
451 	struct mxcmci_host *host = container_of(work, struct mxcmci_host,
452 						  datawork);
453 	int datastat = mxcmci_transfer_data(host);
454 	mxcmci_finish_data(host, datastat);
455 
456 	if (host->req->stop) {
457 		if (mxcmci_start_cmd(host, host->req->stop, 0)) {
458 			mxcmci_finish_request(host, host->req);
459 			return;
460 		}
461 	} else {
462 		mxcmci_finish_request(host, host->req);
463 	}
464 }
465 
466 #ifdef HAS_DMA
467 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat)
468 {
469 	struct mmc_data *data = host->data;
470 	int data_error;
471 
472 	if (!data)
473 		return;
474 
475 	data_error = mxcmci_finish_data(host, stat);
476 
477 	mxcmci_read_response(host, stat);
478 	host->cmd = NULL;
479 
480 	if (host->req->stop) {
481 		if (mxcmci_start_cmd(host, host->req->stop, 0)) {
482 			mxcmci_finish_request(host, host->req);
483 			return;
484 		}
485 	} else {
486 		mxcmci_finish_request(host, host->req);
487 	}
488 }
489 #endif /* HAS_DMA */
490 
491 static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat)
492 {
493 	mxcmci_read_response(host, stat);
494 	host->cmd = NULL;
495 
496 	if (!host->data && host->req) {
497 		mxcmci_finish_request(host, host->req);
498 		return;
499 	}
500 
501 	/* For the DMA case the DMA engine handles the data transfer
502 	 * automatically. For non DMA we have to to it ourselves.
503 	 * Don't do it in interrupt context though.
504 	 */
505 	if (!mxcmci_use_dma(host) && host->data)
506 		schedule_work(&host->datawork);
507 
508 }
509 
510 static irqreturn_t mxcmci_irq(int irq, void *devid)
511 {
512 	struct mxcmci_host *host = devid;
513 	u32 stat;
514 
515 	stat = readl(host->base + MMC_REG_STATUS);
516 	writel(stat, host->base + MMC_REG_STATUS);
517 
518 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
519 
520 	if (stat & STATUS_END_CMD_RESP)
521 		mxcmci_cmd_done(host, stat);
522 #ifdef HAS_DMA
523 	if (mxcmci_use_dma(host) &&
524 		  (stat & (STATUS_DATA_TRANS_DONE | STATUS_WRITE_OP_DONE)))
525 		mxcmci_data_done(host, stat);
526 #endif
527 	return IRQ_HANDLED;
528 }
529 
530 static void mxcmci_request(struct mmc_host *mmc, struct mmc_request *req)
531 {
532 	struct mxcmci_host *host = mmc_priv(mmc);
533 	unsigned int cmdat = host->cmdat;
534 
535 	WARN_ON(host->req != NULL);
536 
537 	host->req = req;
538 	host->cmdat &= ~CMD_DAT_CONT_INIT;
539 #ifdef HAS_DMA
540 	host->do_dma = 1;
541 #endif
542 	if (req->data) {
543 		mxcmci_setup_data(host, req->data);
544 
545 		cmdat |= CMD_DAT_CONT_DATA_ENABLE;
546 
547 		if (req->data->flags & MMC_DATA_WRITE)
548 			cmdat |= CMD_DAT_CONT_WRITE;
549 	}
550 
551 	if (mxcmci_start_cmd(host, req->cmd, cmdat))
552 		mxcmci_finish_request(host, req);
553 }
554 
555 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios)
556 {
557 	unsigned int divider;
558 	int prescaler = 0;
559 	unsigned int clk_in = clk_get_rate(host->clk);
560 
561 	while (prescaler <= 0x800) {
562 		for (divider = 1; divider <= 0xF; divider++) {
563 			int x;
564 
565 			x = (clk_in / (divider + 1));
566 
567 			if (prescaler)
568 				x /= (prescaler * 2);
569 
570 			if (x <= clk_ios)
571 				break;
572 		}
573 		if (divider < 0x10)
574 			break;
575 
576 		if (prescaler == 0)
577 			prescaler = 1;
578 		else
579 			prescaler <<= 1;
580 	}
581 
582 	writew((prescaler << 4) | divider, host->base + MMC_REG_CLK_RATE);
583 
584 	dev_dbg(mmc_dev(host->mmc), "scaler: %d divider: %d in: %d out: %d\n",
585 			prescaler, divider, clk_in, clk_ios);
586 }
587 
588 static void mxcmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
589 {
590 	struct mxcmci_host *host = mmc_priv(mmc);
591 #ifdef HAS_DMA
592 	unsigned int blen;
593 	/*
594 	 * use burstlen of 64 in 4 bit mode (--> reg value  0)
595 	 * use burstlen of 16 in 1 bit mode (--> reg value 16)
596 	 */
597 	if (ios->bus_width == MMC_BUS_WIDTH_4)
598 		blen = 0;
599 	else
600 		blen = 16;
601 
602 	imx_dma_config_burstlen(host->dma, blen);
603 #endif
604 	if (ios->bus_width == MMC_BUS_WIDTH_4)
605 		host->cmdat |= CMD_DAT_CONT_BUS_WIDTH_4;
606 	else
607 		host->cmdat &= ~CMD_DAT_CONT_BUS_WIDTH_4;
608 
609 	if (host->power_mode != ios->power_mode) {
610 		if (host->pdata && host->pdata->setpower)
611 			host->pdata->setpower(mmc_dev(mmc), ios->vdd);
612 		host->power_mode = ios->power_mode;
613 		if (ios->power_mode == MMC_POWER_ON)
614 			host->cmdat |= CMD_DAT_CONT_INIT;
615 	}
616 
617 	if (ios->clock) {
618 		mxcmci_set_clk_rate(host, ios->clock);
619 		writew(STR_STP_CLK_START_CLK, host->base + MMC_REG_STR_STP_CLK);
620 	} else {
621 		writew(STR_STP_CLK_STOP_CLK, host->base + MMC_REG_STR_STP_CLK);
622 	}
623 
624 	host->clock = ios->clock;
625 }
626 
627 static irqreturn_t mxcmci_detect_irq(int irq, void *data)
628 {
629 	struct mmc_host *mmc = data;
630 
631 	dev_dbg(mmc_dev(mmc), "%s\n", __func__);
632 
633 	mmc_detect_change(mmc, msecs_to_jiffies(250));
634 	return IRQ_HANDLED;
635 }
636 
637 static int mxcmci_get_ro(struct mmc_host *mmc)
638 {
639 	struct mxcmci_host *host = mmc_priv(mmc);
640 
641 	if (host->pdata && host->pdata->get_ro)
642 		return !!host->pdata->get_ro(mmc_dev(mmc));
643 	/*
644 	 * Board doesn't support read only detection; let the mmc core
645 	 * decide what to do.
646 	 */
647 	return -ENOSYS;
648 }
649 
650 
651 static const struct mmc_host_ops mxcmci_ops = {
652 	.request	= mxcmci_request,
653 	.set_ios	= mxcmci_set_ios,
654 	.get_ro		= mxcmci_get_ro,
655 };
656 
657 static int mxcmci_probe(struct platform_device *pdev)
658 {
659 	struct mmc_host *mmc;
660 	struct mxcmci_host *host = NULL;
661 	struct resource *r;
662 	int ret = 0, irq;
663 
664 	printk(KERN_INFO "i.MX SDHC driver\n");
665 
666 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
667 	irq = platform_get_irq(pdev, 0);
668 	if (!r || irq < 0)
669 		return -EINVAL;
670 
671 	r = request_mem_region(r->start, resource_size(r), pdev->name);
672 	if (!r)
673 		return -EBUSY;
674 
675 	mmc = mmc_alloc_host(sizeof(struct mxcmci_host), &pdev->dev);
676 	if (!mmc) {
677 		ret = -ENOMEM;
678 		goto out_release_mem;
679 	}
680 
681 	mmc->ops = &mxcmci_ops;
682 	mmc->caps = MMC_CAP_4_BIT_DATA;
683 
684 	/* MMC core transfer sizes tunable parameters */
685 	mmc->max_hw_segs = 64;
686 	mmc->max_phys_segs = 64;
687 	mmc->max_blk_size = 2048;
688 	mmc->max_blk_count = 65535;
689 	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
690 	mmc->max_seg_size = mmc->max_seg_size;
691 
692 	host = mmc_priv(mmc);
693 	host->base = ioremap(r->start, resource_size(r));
694 	if (!host->base) {
695 		ret = -ENOMEM;
696 		goto out_free;
697 	}
698 
699 	host->mmc = mmc;
700 	host->pdata = pdev->dev.platform_data;
701 
702 	if (host->pdata && host->pdata->ocr_avail)
703 		mmc->ocr_avail = host->pdata->ocr_avail;
704 	else
705 		mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
706 
707 	host->res = r;
708 	host->irq = irq;
709 
710 	host->clk = clk_get(&pdev->dev, NULL);
711 	if (IS_ERR(host->clk)) {
712 		ret = PTR_ERR(host->clk);
713 		goto out_iounmap;
714 	}
715 	clk_enable(host->clk);
716 
717 	mxcmci_softreset(host);
718 
719 	host->rev_no = readw(host->base + MMC_REG_REV_NO);
720 	if (host->rev_no != 0x400) {
721 		ret = -ENODEV;
722 		dev_err(mmc_dev(host->mmc), "wrong rev.no. 0x%08x. aborting.\n",
723 			host->rev_no);
724 		goto out_clk_put;
725 	}
726 
727 	mmc->f_min = clk_get_rate(host->clk) >> 7;
728 	mmc->f_max = clk_get_rate(host->clk) >> 1;
729 
730 	/* recommended in data sheet */
731 	writew(0x2db4, host->base + MMC_REG_READ_TO);
732 
733 	writel(0, host->base + MMC_REG_INT_CNTR);
734 
735 #ifdef HAS_DMA
736 	host->dma = imx_dma_request_by_prio(DRIVER_NAME, DMA_PRIO_LOW);
737 	if (host->dma < 0) {
738 		dev_err(mmc_dev(host->mmc), "imx_dma_request_by_prio failed\n");
739 		ret = -EBUSY;
740 		goto out_clk_put;
741 	}
742 
743 	r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
744 	if (!r) {
745 		ret = -EINVAL;
746 		goto out_free_dma;
747 	}
748 
749 	ret = imx_dma_config_channel(host->dma,
750 				     IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_FIFO,
751 				     IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR,
752 				     r->start, 0);
753 	if (ret) {
754 		dev_err(mmc_dev(host->mmc), "failed to config DMA channel\n");
755 		goto out_free_dma;
756 	}
757 #endif
758 	INIT_WORK(&host->datawork, mxcmci_datawork);
759 
760 	ret = request_irq(host->irq, mxcmci_irq, 0, DRIVER_NAME, host);
761 	if (ret)
762 		goto out_free_dma;
763 
764 	platform_set_drvdata(pdev, mmc);
765 
766 	if (host->pdata && host->pdata->init) {
767 		ret = host->pdata->init(&pdev->dev, mxcmci_detect_irq,
768 				host->mmc);
769 		if (ret)
770 			goto out_free_irq;
771 	}
772 
773 	mmc_add_host(mmc);
774 
775 	return 0;
776 
777 out_free_irq:
778 	free_irq(host->irq, host);
779 out_free_dma:
780 #ifdef HAS_DMA
781 	imx_dma_free(host->dma);
782 #endif
783 out_clk_put:
784 	clk_disable(host->clk);
785 	clk_put(host->clk);
786 out_iounmap:
787 	iounmap(host->base);
788 out_free:
789 	mmc_free_host(mmc);
790 out_release_mem:
791 	release_mem_region(host->res->start, resource_size(host->res));
792 	return ret;
793 }
794 
795 static int mxcmci_remove(struct platform_device *pdev)
796 {
797 	struct mmc_host *mmc = platform_get_drvdata(pdev);
798 	struct mxcmci_host *host = mmc_priv(mmc);
799 
800 	platform_set_drvdata(pdev, NULL);
801 
802 	mmc_remove_host(mmc);
803 
804 	if (host->pdata && host->pdata->exit)
805 		host->pdata->exit(&pdev->dev, mmc);
806 
807 	free_irq(host->irq, host);
808 	iounmap(host->base);
809 #ifdef HAS_DMA
810 	imx_dma_free(host->dma);
811 #endif
812 	clk_disable(host->clk);
813 	clk_put(host->clk);
814 
815 	release_mem_region(host->res->start, resource_size(host->res));
816 	release_resource(host->res);
817 
818 	mmc_free_host(mmc);
819 
820 	return 0;
821 }
822 
823 #ifdef CONFIG_PM
824 static int mxcmci_suspend(struct platform_device *dev, pm_message_t state)
825 {
826 	struct mmc_host *mmc = platform_get_drvdata(dev);
827 	int ret = 0;
828 
829 	if (mmc)
830 		ret = mmc_suspend_host(mmc, state);
831 
832 	return ret;
833 }
834 
835 static int mxcmci_resume(struct platform_device *dev)
836 {
837 	struct mmc_host *mmc = platform_get_drvdata(dev);
838 	struct mxcmci_host *host;
839 	int ret = 0;
840 
841 	if (mmc) {
842 		host = mmc_priv(mmc);
843 		ret = mmc_resume_host(mmc);
844 	}
845 
846 	return ret;
847 }
848 #else
849 #define mxcmci_suspend  NULL
850 #define mxcmci_resume   NULL
851 #endif /* CONFIG_PM */
852 
853 static struct platform_driver mxcmci_driver = {
854 	.probe		= mxcmci_probe,
855 	.remove		= mxcmci_remove,
856 	.suspend	= mxcmci_suspend,
857 	.resume		= mxcmci_resume,
858 	.driver		= {
859 		.name		= DRIVER_NAME,
860 		.owner		= THIS_MODULE,
861 	}
862 };
863 
864 static int __init mxcmci_init(void)
865 {
866 	return platform_driver_register(&mxcmci_driver);
867 }
868 
869 static void __exit mxcmci_exit(void)
870 {
871 	platform_driver_unregister(&mxcmci_driver);
872 }
873 
874 module_init(mxcmci_init);
875 module_exit(mxcmci_exit);
876 
877 MODULE_DESCRIPTION("i.MX Multimedia Card Interface Driver");
878 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
879 MODULE_LICENSE("GPL");
880 MODULE_ALIAS("platform:imx-mmc");
881