xref: /openbmc/linux/drivers/mmc/host/mxcmmc.c (revision 95e9fd10)
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 separate 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 #include <linux/regulator/consumer.h>
35 #include <linux/dmaengine.h>
36 #include <linux/types.h>
37 
38 #include <asm/dma.h>
39 #include <asm/irq.h>
40 #include <asm/sizes.h>
41 #include <mach/mmc.h>
42 
43 #include <mach/dma.h>
44 #include <mach/hardware.h>
45 
46 #define DRIVER_NAME "mxc-mmc"
47 
48 #define MMC_REG_STR_STP_CLK		0x00
49 #define MMC_REG_STATUS			0x04
50 #define MMC_REG_CLK_RATE		0x08
51 #define MMC_REG_CMD_DAT_CONT		0x0C
52 #define MMC_REG_RES_TO			0x10
53 #define MMC_REG_READ_TO			0x14
54 #define MMC_REG_BLK_LEN			0x18
55 #define MMC_REG_NOB			0x1C
56 #define MMC_REG_REV_NO			0x20
57 #define MMC_REG_INT_CNTR		0x24
58 #define MMC_REG_CMD			0x28
59 #define MMC_REG_ARG			0x2C
60 #define MMC_REG_RES_FIFO		0x34
61 #define MMC_REG_BUFFER_ACCESS		0x38
62 
63 #define STR_STP_CLK_RESET               (1 << 3)
64 #define STR_STP_CLK_START_CLK           (1 << 1)
65 #define STR_STP_CLK_STOP_CLK            (1 << 0)
66 
67 #define STATUS_CARD_INSERTION		(1 << 31)
68 #define STATUS_CARD_REMOVAL		(1 << 30)
69 #define STATUS_YBUF_EMPTY		(1 << 29)
70 #define STATUS_XBUF_EMPTY		(1 << 28)
71 #define STATUS_YBUF_FULL		(1 << 27)
72 #define STATUS_XBUF_FULL		(1 << 26)
73 #define STATUS_BUF_UND_RUN		(1 << 25)
74 #define STATUS_BUF_OVFL			(1 << 24)
75 #define STATUS_SDIO_INT_ACTIVE		(1 << 14)
76 #define STATUS_END_CMD_RESP		(1 << 13)
77 #define STATUS_WRITE_OP_DONE		(1 << 12)
78 #define STATUS_DATA_TRANS_DONE		(1 << 11)
79 #define STATUS_READ_OP_DONE		(1 << 11)
80 #define STATUS_WR_CRC_ERROR_CODE_MASK	(3 << 10)
81 #define STATUS_CARD_BUS_CLK_RUN		(1 << 8)
82 #define STATUS_BUF_READ_RDY		(1 << 7)
83 #define STATUS_BUF_WRITE_RDY		(1 << 6)
84 #define STATUS_RESP_CRC_ERR		(1 << 5)
85 #define STATUS_CRC_READ_ERR		(1 << 3)
86 #define STATUS_CRC_WRITE_ERR		(1 << 2)
87 #define STATUS_TIME_OUT_RESP		(1 << 1)
88 #define STATUS_TIME_OUT_READ		(1 << 0)
89 #define STATUS_ERR_MASK			0x2f
90 
91 #define CMD_DAT_CONT_CMD_RESP_LONG_OFF	(1 << 12)
92 #define CMD_DAT_CONT_STOP_READWAIT	(1 << 11)
93 #define CMD_DAT_CONT_START_READWAIT	(1 << 10)
94 #define CMD_DAT_CONT_BUS_WIDTH_4	(2 << 8)
95 #define CMD_DAT_CONT_INIT		(1 << 7)
96 #define CMD_DAT_CONT_WRITE		(1 << 4)
97 #define CMD_DAT_CONT_DATA_ENABLE	(1 << 3)
98 #define CMD_DAT_CONT_RESPONSE_48BIT_CRC	(1 << 0)
99 #define CMD_DAT_CONT_RESPONSE_136BIT	(2 << 0)
100 #define CMD_DAT_CONT_RESPONSE_48BIT	(3 << 0)
101 
102 #define INT_SDIO_INT_WKP_EN		(1 << 18)
103 #define INT_CARD_INSERTION_WKP_EN	(1 << 17)
104 #define INT_CARD_REMOVAL_WKP_EN		(1 << 16)
105 #define INT_CARD_INSERTION_EN		(1 << 15)
106 #define INT_CARD_REMOVAL_EN		(1 << 14)
107 #define INT_SDIO_IRQ_EN			(1 << 13)
108 #define INT_DAT0_EN			(1 << 12)
109 #define INT_BUF_READ_EN			(1 << 4)
110 #define INT_BUF_WRITE_EN		(1 << 3)
111 #define INT_END_CMD_RES_EN		(1 << 2)
112 #define INT_WRITE_OP_DONE_EN		(1 << 1)
113 #define INT_READ_OP_EN			(1 << 0)
114 
115 struct mxcmci_host {
116 	struct mmc_host		*mmc;
117 	struct resource		*res;
118 	void __iomem		*base;
119 	int			irq;
120 	int			detect_irq;
121 	struct dma_chan		*dma;
122 	struct dma_async_tx_descriptor *desc;
123 	int			do_dma;
124 	int			default_irq_mask;
125 	int			use_sdio;
126 	unsigned int		power_mode;
127 	struct imxmmc_platform_data *pdata;
128 
129 	struct mmc_request	*req;
130 	struct mmc_command	*cmd;
131 	struct mmc_data		*data;
132 
133 	unsigned int		datasize;
134 	unsigned int		dma_dir;
135 
136 	u16			rev_no;
137 	unsigned int		cmdat;
138 
139 	struct clk		*clk_ipg;
140 	struct clk		*clk_per;
141 
142 	int			clock;
143 
144 	struct work_struct	datawork;
145 	spinlock_t		lock;
146 
147 	struct regulator	*vcc;
148 
149 	int			burstlen;
150 	int			dmareq;
151 	struct dma_slave_config dma_slave_config;
152 	struct imx_dma_data	dma_data;
153 };
154 
155 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios);
156 
157 static inline void mxcmci_init_ocr(struct mxcmci_host *host)
158 {
159 	host->vcc = regulator_get(mmc_dev(host->mmc), "vmmc");
160 
161 	if (IS_ERR(host->vcc)) {
162 		host->vcc = NULL;
163 	} else {
164 		host->mmc->ocr_avail = mmc_regulator_get_ocrmask(host->vcc);
165 		if (host->pdata && host->pdata->ocr_avail)
166 			dev_warn(mmc_dev(host->mmc),
167 				"pdata->ocr_avail will not be used\n");
168 	}
169 
170 	if (host->vcc == NULL) {
171 		/* fall-back to platform data */
172 		if (host->pdata && host->pdata->ocr_avail)
173 			host->mmc->ocr_avail = host->pdata->ocr_avail;
174 		else
175 			host->mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
176 	}
177 }
178 
179 static inline void mxcmci_set_power(struct mxcmci_host *host,
180 				    unsigned char power_mode,
181 				    unsigned int vdd)
182 {
183 	if (host->vcc) {
184 		if (power_mode == MMC_POWER_UP)
185 			mmc_regulator_set_ocr(host->mmc, host->vcc, vdd);
186 		else if (power_mode == MMC_POWER_OFF)
187 			mmc_regulator_set_ocr(host->mmc, host->vcc, 0);
188 	}
189 
190 	if (host->pdata && host->pdata->setpower)
191 		host->pdata->setpower(mmc_dev(host->mmc), vdd);
192 }
193 
194 static inline int mxcmci_use_dma(struct mxcmci_host *host)
195 {
196 	return host->do_dma;
197 }
198 
199 static void mxcmci_softreset(struct mxcmci_host *host)
200 {
201 	int i;
202 
203 	dev_dbg(mmc_dev(host->mmc), "mxcmci_softreset\n");
204 
205 	/* reset sequence */
206 	writew(STR_STP_CLK_RESET, host->base + MMC_REG_STR_STP_CLK);
207 	writew(STR_STP_CLK_RESET | STR_STP_CLK_START_CLK,
208 			host->base + MMC_REG_STR_STP_CLK);
209 
210 	for (i = 0; i < 8; i++)
211 		writew(STR_STP_CLK_START_CLK, host->base + MMC_REG_STR_STP_CLK);
212 
213 	writew(0xff, host->base + MMC_REG_RES_TO);
214 }
215 static int mxcmci_setup_dma(struct mmc_host *mmc);
216 
217 static int mxcmci_setup_data(struct mxcmci_host *host, struct mmc_data *data)
218 {
219 	unsigned int nob = data->blocks;
220 	unsigned int blksz = data->blksz;
221 	unsigned int datasize = nob * blksz;
222 	struct scatterlist *sg;
223 	enum dma_transfer_direction slave_dirn;
224 	int i, nents;
225 
226 	if (data->flags & MMC_DATA_STREAM)
227 		nob = 0xffff;
228 
229 	host->data = data;
230 	data->bytes_xfered = 0;
231 
232 	writew(nob, host->base + MMC_REG_NOB);
233 	writew(blksz, host->base + MMC_REG_BLK_LEN);
234 	host->datasize = datasize;
235 
236 	if (!mxcmci_use_dma(host))
237 		return 0;
238 
239 	for_each_sg(data->sg, sg, data->sg_len, i) {
240 		if (sg->offset & 3 || sg->length & 3) {
241 			host->do_dma = 0;
242 			return 0;
243 		}
244 	}
245 
246 	if (data->flags & MMC_DATA_READ) {
247 		host->dma_dir = DMA_FROM_DEVICE;
248 		slave_dirn = DMA_DEV_TO_MEM;
249 	} else {
250 		host->dma_dir = DMA_TO_DEVICE;
251 		slave_dirn = DMA_MEM_TO_DEV;
252 	}
253 
254 	nents = dma_map_sg(host->dma->device->dev, data->sg,
255 				     data->sg_len,  host->dma_dir);
256 	if (nents != data->sg_len)
257 		return -EINVAL;
258 
259 	host->desc = dmaengine_prep_slave_sg(host->dma,
260 		data->sg, data->sg_len, slave_dirn,
261 		DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
262 
263 	if (!host->desc) {
264 		dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
265 				host->dma_dir);
266 		host->do_dma = 0;
267 		return 0; /* Fall back to PIO */
268 	}
269 	wmb();
270 
271 	dmaengine_submit(host->desc);
272 	dma_async_issue_pending(host->dma);
273 
274 	return 0;
275 }
276 
277 static int mxcmci_start_cmd(struct mxcmci_host *host, struct mmc_command *cmd,
278 		unsigned int cmdat)
279 {
280 	u32 int_cntr = host->default_irq_mask;
281 	unsigned long flags;
282 
283 	WARN_ON(host->cmd != NULL);
284 	host->cmd = cmd;
285 
286 	switch (mmc_resp_type(cmd)) {
287 	case MMC_RSP_R1: /* short CRC, OPCODE */
288 	case MMC_RSP_R1B:/* short CRC, OPCODE, BUSY */
289 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT_CRC;
290 		break;
291 	case MMC_RSP_R2: /* long 136 bit + CRC */
292 		cmdat |= CMD_DAT_CONT_RESPONSE_136BIT;
293 		break;
294 	case MMC_RSP_R3: /* short */
295 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT;
296 		break;
297 	case MMC_RSP_NONE:
298 		break;
299 	default:
300 		dev_err(mmc_dev(host->mmc), "unhandled response type 0x%x\n",
301 				mmc_resp_type(cmd));
302 		cmd->error = -EINVAL;
303 		return -EINVAL;
304 	}
305 
306 	int_cntr = INT_END_CMD_RES_EN;
307 
308 	if (mxcmci_use_dma(host))
309 		int_cntr |= INT_READ_OP_EN | INT_WRITE_OP_DONE_EN;
310 
311 	spin_lock_irqsave(&host->lock, flags);
312 	if (host->use_sdio)
313 		int_cntr |= INT_SDIO_IRQ_EN;
314 	writel(int_cntr, host->base + MMC_REG_INT_CNTR);
315 	spin_unlock_irqrestore(&host->lock, flags);
316 
317 	writew(cmd->opcode, host->base + MMC_REG_CMD);
318 	writel(cmd->arg, host->base + MMC_REG_ARG);
319 	writew(cmdat, host->base + MMC_REG_CMD_DAT_CONT);
320 
321 	return 0;
322 }
323 
324 static void mxcmci_finish_request(struct mxcmci_host *host,
325 		struct mmc_request *req)
326 {
327 	u32 int_cntr = host->default_irq_mask;
328 	unsigned long flags;
329 
330 	spin_lock_irqsave(&host->lock, flags);
331 	if (host->use_sdio)
332 		int_cntr |= INT_SDIO_IRQ_EN;
333 	writel(int_cntr, host->base + MMC_REG_INT_CNTR);
334 	spin_unlock_irqrestore(&host->lock, flags);
335 
336 	host->req = NULL;
337 	host->cmd = NULL;
338 	host->data = NULL;
339 
340 	mmc_request_done(host->mmc, req);
341 }
342 
343 static int mxcmci_finish_data(struct mxcmci_host *host, unsigned int stat)
344 {
345 	struct mmc_data *data = host->data;
346 	int data_error;
347 
348 	if (mxcmci_use_dma(host)) {
349 		dmaengine_terminate_all(host->dma);
350 		dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
351 				host->dma_dir);
352 	}
353 
354 	if (stat & STATUS_ERR_MASK) {
355 		dev_dbg(mmc_dev(host->mmc), "request failed. status: 0x%08x\n",
356 				stat);
357 		if (stat & STATUS_CRC_READ_ERR) {
358 			dev_err(mmc_dev(host->mmc), "%s: -EILSEQ\n", __func__);
359 			data->error = -EILSEQ;
360 		} else if (stat & STATUS_CRC_WRITE_ERR) {
361 			u32 err_code = (stat >> 9) & 0x3;
362 			if (err_code == 2) { /* No CRC response */
363 				dev_err(mmc_dev(host->mmc),
364 					"%s: No CRC -ETIMEDOUT\n", __func__);
365 				data->error = -ETIMEDOUT;
366 			} else {
367 				dev_err(mmc_dev(host->mmc),
368 					"%s: -EILSEQ\n", __func__);
369 				data->error = -EILSEQ;
370 			}
371 		} else if (stat & STATUS_TIME_OUT_READ) {
372 			dev_err(mmc_dev(host->mmc),
373 				"%s: read -ETIMEDOUT\n", __func__);
374 			data->error = -ETIMEDOUT;
375 		} else {
376 			dev_err(mmc_dev(host->mmc), "%s: -EIO\n", __func__);
377 			data->error = -EIO;
378 		}
379 	} else {
380 		data->bytes_xfered = host->datasize;
381 	}
382 
383 	data_error = data->error;
384 
385 	host->data = NULL;
386 
387 	return data_error;
388 }
389 
390 static void mxcmci_read_response(struct mxcmci_host *host, unsigned int stat)
391 {
392 	struct mmc_command *cmd = host->cmd;
393 	int i;
394 	u32 a, b, c;
395 
396 	if (!cmd)
397 		return;
398 
399 	if (stat & STATUS_TIME_OUT_RESP) {
400 		dev_dbg(mmc_dev(host->mmc), "CMD TIMEOUT\n");
401 		cmd->error = -ETIMEDOUT;
402 	} else if (stat & STATUS_RESP_CRC_ERR && cmd->flags & MMC_RSP_CRC) {
403 		dev_dbg(mmc_dev(host->mmc), "cmd crc error\n");
404 		cmd->error = -EILSEQ;
405 	}
406 
407 	if (cmd->flags & MMC_RSP_PRESENT) {
408 		if (cmd->flags & MMC_RSP_136) {
409 			for (i = 0; i < 4; i++) {
410 				a = readw(host->base + MMC_REG_RES_FIFO);
411 				b = readw(host->base + MMC_REG_RES_FIFO);
412 				cmd->resp[i] = a << 16 | b;
413 			}
414 		} else {
415 			a = readw(host->base + MMC_REG_RES_FIFO);
416 			b = readw(host->base + MMC_REG_RES_FIFO);
417 			c = readw(host->base + MMC_REG_RES_FIFO);
418 			cmd->resp[0] = a << 24 | b << 8 | c >> 8;
419 		}
420 	}
421 }
422 
423 static int mxcmci_poll_status(struct mxcmci_host *host, u32 mask)
424 {
425 	u32 stat;
426 	unsigned long timeout = jiffies + HZ;
427 
428 	do {
429 		stat = readl(host->base + MMC_REG_STATUS);
430 		if (stat & STATUS_ERR_MASK)
431 			return stat;
432 		if (time_after(jiffies, timeout)) {
433 			mxcmci_softreset(host);
434 			mxcmci_set_clk_rate(host, host->clock);
435 			return STATUS_TIME_OUT_READ;
436 		}
437 		if (stat & mask)
438 			return 0;
439 		cpu_relax();
440 	} while (1);
441 }
442 
443 static int mxcmci_pull(struct mxcmci_host *host, void *_buf, int bytes)
444 {
445 	unsigned int stat;
446 	u32 *buf = _buf;
447 
448 	while (bytes > 3) {
449 		stat = mxcmci_poll_status(host,
450 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
451 		if (stat)
452 			return stat;
453 		*buf++ = readl(host->base + MMC_REG_BUFFER_ACCESS);
454 		bytes -= 4;
455 	}
456 
457 	if (bytes) {
458 		u8 *b = (u8 *)buf;
459 		u32 tmp;
460 
461 		stat = mxcmci_poll_status(host,
462 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
463 		if (stat)
464 			return stat;
465 		tmp = readl(host->base + MMC_REG_BUFFER_ACCESS);
466 		memcpy(b, &tmp, bytes);
467 	}
468 
469 	return 0;
470 }
471 
472 static int mxcmci_push(struct mxcmci_host *host, void *_buf, int bytes)
473 {
474 	unsigned int stat;
475 	u32 *buf = _buf;
476 
477 	while (bytes > 3) {
478 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
479 		if (stat)
480 			return stat;
481 		writel(*buf++, host->base + MMC_REG_BUFFER_ACCESS);
482 		bytes -= 4;
483 	}
484 
485 	if (bytes) {
486 		u8 *b = (u8 *)buf;
487 		u32 tmp;
488 
489 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
490 		if (stat)
491 			return stat;
492 
493 		memcpy(&tmp, b, bytes);
494 		writel(tmp, host->base + MMC_REG_BUFFER_ACCESS);
495 	}
496 
497 	stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
498 	if (stat)
499 		return stat;
500 
501 	return 0;
502 }
503 
504 static int mxcmci_transfer_data(struct mxcmci_host *host)
505 {
506 	struct mmc_data *data = host->req->data;
507 	struct scatterlist *sg;
508 	int stat, i;
509 
510 	host->data = data;
511 	host->datasize = 0;
512 
513 	if (data->flags & MMC_DATA_READ) {
514 		for_each_sg(data->sg, sg, data->sg_len, i) {
515 			stat = mxcmci_pull(host, sg_virt(sg), sg->length);
516 			if (stat)
517 				return stat;
518 			host->datasize += sg->length;
519 		}
520 	} else {
521 		for_each_sg(data->sg, sg, data->sg_len, i) {
522 			stat = mxcmci_push(host, sg_virt(sg), sg->length);
523 			if (stat)
524 				return stat;
525 			host->datasize += sg->length;
526 		}
527 		stat = mxcmci_poll_status(host, STATUS_WRITE_OP_DONE);
528 		if (stat)
529 			return stat;
530 	}
531 	return 0;
532 }
533 
534 static void mxcmci_datawork(struct work_struct *work)
535 {
536 	struct mxcmci_host *host = container_of(work, struct mxcmci_host,
537 						  datawork);
538 	int datastat = mxcmci_transfer_data(host);
539 
540 	writel(STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE,
541 		host->base + MMC_REG_STATUS);
542 	mxcmci_finish_data(host, datastat);
543 
544 	if (host->req->stop) {
545 		if (mxcmci_start_cmd(host, host->req->stop, 0)) {
546 			mxcmci_finish_request(host, host->req);
547 			return;
548 		}
549 	} else {
550 		mxcmci_finish_request(host, host->req);
551 	}
552 }
553 
554 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat)
555 {
556 	struct mmc_data *data = host->data;
557 	int data_error;
558 
559 	if (!data)
560 		return;
561 
562 	data_error = mxcmci_finish_data(host, stat);
563 
564 	mxcmci_read_response(host, stat);
565 	host->cmd = NULL;
566 
567 	if (host->req->stop) {
568 		if (mxcmci_start_cmd(host, host->req->stop, 0)) {
569 			mxcmci_finish_request(host, host->req);
570 			return;
571 		}
572 	} else {
573 		mxcmci_finish_request(host, host->req);
574 	}
575 }
576 
577 static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat)
578 {
579 	mxcmci_read_response(host, stat);
580 	host->cmd = NULL;
581 
582 	if (!host->data && host->req) {
583 		mxcmci_finish_request(host, host->req);
584 		return;
585 	}
586 
587 	/* For the DMA case the DMA engine handles the data transfer
588 	 * automatically. For non DMA we have to do it ourselves.
589 	 * Don't do it in interrupt context though.
590 	 */
591 	if (!mxcmci_use_dma(host) && host->data)
592 		schedule_work(&host->datawork);
593 
594 }
595 
596 static irqreturn_t mxcmci_irq(int irq, void *devid)
597 {
598 	struct mxcmci_host *host = devid;
599 	unsigned long flags;
600 	bool sdio_irq;
601 	u32 stat;
602 
603 	stat = readl(host->base + MMC_REG_STATUS);
604 	writel(stat & ~(STATUS_SDIO_INT_ACTIVE | STATUS_DATA_TRANS_DONE |
605 			STATUS_WRITE_OP_DONE), host->base + MMC_REG_STATUS);
606 
607 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
608 
609 	spin_lock_irqsave(&host->lock, flags);
610 	sdio_irq = (stat & STATUS_SDIO_INT_ACTIVE) && host->use_sdio;
611 	spin_unlock_irqrestore(&host->lock, flags);
612 
613 	if (mxcmci_use_dma(host) &&
614 	    (stat & (STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE)))
615 		writel(STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE,
616 			host->base + MMC_REG_STATUS);
617 
618 	if (sdio_irq) {
619 		writel(STATUS_SDIO_INT_ACTIVE, host->base + MMC_REG_STATUS);
620 		mmc_signal_sdio_irq(host->mmc);
621 	}
622 
623 	if (stat & STATUS_END_CMD_RESP)
624 		mxcmci_cmd_done(host, stat);
625 
626 	if (mxcmci_use_dma(host) &&
627 		  (stat & (STATUS_DATA_TRANS_DONE | STATUS_WRITE_OP_DONE)))
628 		mxcmci_data_done(host, stat);
629 
630 	if (host->default_irq_mask &&
631 		  (stat & (STATUS_CARD_INSERTION | STATUS_CARD_REMOVAL)))
632 		mmc_detect_change(host->mmc, msecs_to_jiffies(200));
633 
634 	return IRQ_HANDLED;
635 }
636 
637 static void mxcmci_request(struct mmc_host *mmc, struct mmc_request *req)
638 {
639 	struct mxcmci_host *host = mmc_priv(mmc);
640 	unsigned int cmdat = host->cmdat;
641 	int error;
642 
643 	WARN_ON(host->req != NULL);
644 
645 	host->req = req;
646 	host->cmdat &= ~CMD_DAT_CONT_INIT;
647 
648 	if (host->dma)
649 		host->do_dma = 1;
650 
651 	if (req->data) {
652 		error = mxcmci_setup_data(host, req->data);
653 		if (error) {
654 			req->cmd->error = error;
655 			goto out;
656 		}
657 
658 
659 		cmdat |= CMD_DAT_CONT_DATA_ENABLE;
660 
661 		if (req->data->flags & MMC_DATA_WRITE)
662 			cmdat |= CMD_DAT_CONT_WRITE;
663 	}
664 
665 	error = mxcmci_start_cmd(host, req->cmd, cmdat);
666 
667 out:
668 	if (error)
669 		mxcmci_finish_request(host, req);
670 }
671 
672 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios)
673 {
674 	unsigned int divider;
675 	int prescaler = 0;
676 	unsigned int clk_in = clk_get_rate(host->clk_per);
677 
678 	while (prescaler <= 0x800) {
679 		for (divider = 1; divider <= 0xF; divider++) {
680 			int x;
681 
682 			x = (clk_in / (divider + 1));
683 
684 			if (prescaler)
685 				x /= (prescaler * 2);
686 
687 			if (x <= clk_ios)
688 				break;
689 		}
690 		if (divider < 0x10)
691 			break;
692 
693 		if (prescaler == 0)
694 			prescaler = 1;
695 		else
696 			prescaler <<= 1;
697 	}
698 
699 	writew((prescaler << 4) | divider, host->base + MMC_REG_CLK_RATE);
700 
701 	dev_dbg(mmc_dev(host->mmc), "scaler: %d divider: %d in: %d out: %d\n",
702 			prescaler, divider, clk_in, clk_ios);
703 }
704 
705 static int mxcmci_setup_dma(struct mmc_host *mmc)
706 {
707 	struct mxcmci_host *host = mmc_priv(mmc);
708 	struct dma_slave_config *config = &host->dma_slave_config;
709 
710 	config->dst_addr = host->res->start + MMC_REG_BUFFER_ACCESS;
711 	config->src_addr = host->res->start + MMC_REG_BUFFER_ACCESS;
712 	config->dst_addr_width = 4;
713 	config->src_addr_width = 4;
714 	config->dst_maxburst = host->burstlen;
715 	config->src_maxburst = host->burstlen;
716 	config->device_fc = false;
717 
718 	return dmaengine_slave_config(host->dma, config);
719 }
720 
721 static void mxcmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
722 {
723 	struct mxcmci_host *host = mmc_priv(mmc);
724 	int burstlen, ret;
725 
726 	/*
727 	 * use burstlen of 64 (16 words) in 4 bit mode (--> reg value  0)
728 	 * use burstlen of 16 (4 words) in 1 bit mode (--> reg value 16)
729 	 */
730 	if (ios->bus_width == MMC_BUS_WIDTH_4)
731 		burstlen = 16;
732 	else
733 		burstlen = 4;
734 
735 	if (mxcmci_use_dma(host) && burstlen != host->burstlen) {
736 		host->burstlen = burstlen;
737 		ret = mxcmci_setup_dma(mmc);
738 		if (ret) {
739 			dev_err(mmc_dev(host->mmc),
740 				"failed to config DMA channel. Falling back to PIO\n");
741 			dma_release_channel(host->dma);
742 			host->do_dma = 0;
743 			host->dma = NULL;
744 		}
745 	}
746 
747 	if (ios->bus_width == MMC_BUS_WIDTH_4)
748 		host->cmdat |= CMD_DAT_CONT_BUS_WIDTH_4;
749 	else
750 		host->cmdat &= ~CMD_DAT_CONT_BUS_WIDTH_4;
751 
752 	if (host->power_mode != ios->power_mode) {
753 		mxcmci_set_power(host, ios->power_mode, ios->vdd);
754 		host->power_mode = ios->power_mode;
755 
756 		if (ios->power_mode == MMC_POWER_ON)
757 			host->cmdat |= CMD_DAT_CONT_INIT;
758 	}
759 
760 	if (ios->clock) {
761 		mxcmci_set_clk_rate(host, ios->clock);
762 		writew(STR_STP_CLK_START_CLK, host->base + MMC_REG_STR_STP_CLK);
763 	} else {
764 		writew(STR_STP_CLK_STOP_CLK, host->base + MMC_REG_STR_STP_CLK);
765 	}
766 
767 	host->clock = ios->clock;
768 }
769 
770 static irqreturn_t mxcmci_detect_irq(int irq, void *data)
771 {
772 	struct mmc_host *mmc = data;
773 
774 	dev_dbg(mmc_dev(mmc), "%s\n", __func__);
775 
776 	mmc_detect_change(mmc, msecs_to_jiffies(250));
777 	return IRQ_HANDLED;
778 }
779 
780 static int mxcmci_get_ro(struct mmc_host *mmc)
781 {
782 	struct mxcmci_host *host = mmc_priv(mmc);
783 
784 	if (host->pdata && host->pdata->get_ro)
785 		return !!host->pdata->get_ro(mmc_dev(mmc));
786 	/*
787 	 * Board doesn't support read only detection; let the mmc core
788 	 * decide what to do.
789 	 */
790 	return -ENOSYS;
791 }
792 
793 static void mxcmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
794 {
795 	struct mxcmci_host *host = mmc_priv(mmc);
796 	unsigned long flags;
797 	u32 int_cntr;
798 
799 	spin_lock_irqsave(&host->lock, flags);
800 	host->use_sdio = enable;
801 	int_cntr = readl(host->base + MMC_REG_INT_CNTR);
802 
803 	if (enable)
804 		int_cntr |= INT_SDIO_IRQ_EN;
805 	else
806 		int_cntr &= ~INT_SDIO_IRQ_EN;
807 
808 	writel(int_cntr, host->base + MMC_REG_INT_CNTR);
809 	spin_unlock_irqrestore(&host->lock, flags);
810 }
811 
812 static void mxcmci_init_card(struct mmc_host *host, struct mmc_card *card)
813 {
814 	/*
815 	 * MX3 SoCs have a silicon bug which corrupts CRC calculation of
816 	 * multi-block transfers when connected SDIO peripheral doesn't
817 	 * drive the BUSY line as required by the specs.
818 	 * One way to prevent this is to only allow 1-bit transfers.
819 	 */
820 
821 	if (cpu_is_mx3() && card->type == MMC_TYPE_SDIO)
822 		host->caps &= ~MMC_CAP_4_BIT_DATA;
823 	else
824 		host->caps |= MMC_CAP_4_BIT_DATA;
825 }
826 
827 static bool filter(struct dma_chan *chan, void *param)
828 {
829 	struct mxcmci_host *host = param;
830 
831 	if (!imx_dma_is_general_purpose(chan))
832 		return false;
833 
834 	chan->private = &host->dma_data;
835 
836 	return true;
837 }
838 
839 static const struct mmc_host_ops mxcmci_ops = {
840 	.request		= mxcmci_request,
841 	.set_ios		= mxcmci_set_ios,
842 	.get_ro			= mxcmci_get_ro,
843 	.enable_sdio_irq	= mxcmci_enable_sdio_irq,
844 	.init_card		= mxcmci_init_card,
845 };
846 
847 static int mxcmci_probe(struct platform_device *pdev)
848 {
849 	struct mmc_host *mmc;
850 	struct mxcmci_host *host = NULL;
851 	struct resource *iores, *r;
852 	int ret = 0, irq;
853 	dma_cap_mask_t mask;
854 
855 	pr_info("i.MX SDHC driver\n");
856 
857 	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
858 	irq = platform_get_irq(pdev, 0);
859 	if (!iores || irq < 0)
860 		return -EINVAL;
861 
862 	r = request_mem_region(iores->start, resource_size(iores), pdev->name);
863 	if (!r)
864 		return -EBUSY;
865 
866 	mmc = mmc_alloc_host(sizeof(struct mxcmci_host), &pdev->dev);
867 	if (!mmc) {
868 		ret = -ENOMEM;
869 		goto out_release_mem;
870 	}
871 
872 	mmc->ops = &mxcmci_ops;
873 	mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
874 
875 	/* MMC core transfer sizes tunable parameters */
876 	mmc->max_segs = 64;
877 	mmc->max_blk_size = 2048;
878 	mmc->max_blk_count = 65535;
879 	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
880 	mmc->max_seg_size = mmc->max_req_size;
881 
882 	host = mmc_priv(mmc);
883 	host->base = ioremap(r->start, resource_size(r));
884 	if (!host->base) {
885 		ret = -ENOMEM;
886 		goto out_free;
887 	}
888 
889 	host->mmc = mmc;
890 	host->pdata = pdev->dev.platform_data;
891 	spin_lock_init(&host->lock);
892 
893 	mxcmci_init_ocr(host);
894 
895 	if (host->pdata && host->pdata->dat3_card_detect)
896 		host->default_irq_mask =
897 			INT_CARD_INSERTION_EN | INT_CARD_REMOVAL_EN;
898 	else
899 		host->default_irq_mask = 0;
900 
901 	host->res = r;
902 	host->irq = irq;
903 
904 	host->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
905 	if (IS_ERR(host->clk_ipg)) {
906 		ret = PTR_ERR(host->clk_ipg);
907 		goto out_iounmap;
908 	}
909 
910 	host->clk_per = devm_clk_get(&pdev->dev, "per");
911 	if (IS_ERR(host->clk_per)) {
912 		ret = PTR_ERR(host->clk_per);
913 		goto out_iounmap;
914 	}
915 
916 	clk_prepare_enable(host->clk_per);
917 	clk_prepare_enable(host->clk_ipg);
918 
919 	mxcmci_softreset(host);
920 
921 	host->rev_no = readw(host->base + MMC_REG_REV_NO);
922 	if (host->rev_no != 0x400) {
923 		ret = -ENODEV;
924 		dev_err(mmc_dev(host->mmc), "wrong rev.no. 0x%08x. aborting.\n",
925 			host->rev_no);
926 		goto out_clk_put;
927 	}
928 
929 	mmc->f_min = clk_get_rate(host->clk_per) >> 16;
930 	mmc->f_max = clk_get_rate(host->clk_per) >> 1;
931 
932 	/* recommended in data sheet */
933 	writew(0x2db4, host->base + MMC_REG_READ_TO);
934 
935 	writel(host->default_irq_mask, host->base + MMC_REG_INT_CNTR);
936 
937 	r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
938 	if (r) {
939 		host->dmareq = r->start;
940 		host->dma_data.peripheral_type = IMX_DMATYPE_SDHC;
941 		host->dma_data.priority = DMA_PRIO_LOW;
942 		host->dma_data.dma_request = host->dmareq;
943 		dma_cap_zero(mask);
944 		dma_cap_set(DMA_SLAVE, mask);
945 		host->dma = dma_request_channel(mask, filter, host);
946 		if (host->dma)
947 			mmc->max_seg_size = dma_get_max_seg_size(
948 					host->dma->device->dev);
949 	}
950 
951 	if (!host->dma)
952 		dev_info(mmc_dev(host->mmc), "dma not available. Using PIO\n");
953 
954 	INIT_WORK(&host->datawork, mxcmci_datawork);
955 
956 	ret = request_irq(host->irq, mxcmci_irq, 0, DRIVER_NAME, host);
957 	if (ret)
958 		goto out_free_dma;
959 
960 	platform_set_drvdata(pdev, mmc);
961 
962 	if (host->pdata && host->pdata->init) {
963 		ret = host->pdata->init(&pdev->dev, mxcmci_detect_irq,
964 				host->mmc);
965 		if (ret)
966 			goto out_free_irq;
967 	}
968 
969 	mmc_add_host(mmc);
970 
971 	return 0;
972 
973 out_free_irq:
974 	free_irq(host->irq, host);
975 out_free_dma:
976 	if (host->dma)
977 		dma_release_channel(host->dma);
978 out_clk_put:
979 	clk_disable_unprepare(host->clk_per);
980 	clk_disable_unprepare(host->clk_ipg);
981 out_iounmap:
982 	iounmap(host->base);
983 out_free:
984 	mmc_free_host(mmc);
985 out_release_mem:
986 	release_mem_region(iores->start, resource_size(iores));
987 	return ret;
988 }
989 
990 static int mxcmci_remove(struct platform_device *pdev)
991 {
992 	struct mmc_host *mmc = platform_get_drvdata(pdev);
993 	struct mxcmci_host *host = mmc_priv(mmc);
994 
995 	platform_set_drvdata(pdev, NULL);
996 
997 	mmc_remove_host(mmc);
998 
999 	if (host->vcc)
1000 		regulator_put(host->vcc);
1001 
1002 	if (host->pdata && host->pdata->exit)
1003 		host->pdata->exit(&pdev->dev, mmc);
1004 
1005 	free_irq(host->irq, host);
1006 	iounmap(host->base);
1007 
1008 	if (host->dma)
1009 		dma_release_channel(host->dma);
1010 
1011 	clk_disable_unprepare(host->clk_per);
1012 	clk_disable_unprepare(host->clk_ipg);
1013 
1014 	release_mem_region(host->res->start, resource_size(host->res));
1015 
1016 	mmc_free_host(mmc);
1017 
1018 	return 0;
1019 }
1020 
1021 #ifdef CONFIG_PM
1022 static int mxcmci_suspend(struct device *dev)
1023 {
1024 	struct mmc_host *mmc = dev_get_drvdata(dev);
1025 	struct mxcmci_host *host = mmc_priv(mmc);
1026 	int ret = 0;
1027 
1028 	if (mmc)
1029 		ret = mmc_suspend_host(mmc);
1030 	clk_disable_unprepare(host->clk_per);
1031 	clk_disable_unprepare(host->clk_ipg);
1032 
1033 	return ret;
1034 }
1035 
1036 static int mxcmci_resume(struct device *dev)
1037 {
1038 	struct mmc_host *mmc = dev_get_drvdata(dev);
1039 	struct mxcmci_host *host = mmc_priv(mmc);
1040 	int ret = 0;
1041 
1042 	clk_prepare_enable(host->clk_per);
1043 	clk_prepare_enable(host->clk_ipg);
1044 	if (mmc)
1045 		ret = mmc_resume_host(mmc);
1046 
1047 	return ret;
1048 }
1049 
1050 static const struct dev_pm_ops mxcmci_pm_ops = {
1051 	.suspend	= mxcmci_suspend,
1052 	.resume		= mxcmci_resume,
1053 };
1054 #endif
1055 
1056 static struct platform_driver mxcmci_driver = {
1057 	.probe		= mxcmci_probe,
1058 	.remove		= mxcmci_remove,
1059 	.driver		= {
1060 		.name		= DRIVER_NAME,
1061 		.owner		= THIS_MODULE,
1062 #ifdef CONFIG_PM
1063 		.pm	= &mxcmci_pm_ops,
1064 #endif
1065 	}
1066 };
1067 
1068 module_platform_driver(mxcmci_driver);
1069 
1070 MODULE_DESCRIPTION("i.MX Multimedia Card Interface Driver");
1071 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1072 MODULE_LICENSE("GPL");
1073 MODULE_ALIAS("platform:imx-mmc");
1074