xref: /openbmc/linux/drivers/mmc/host/mxcmmc.c (revision 8fdff1dc)
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 <linux/platform_data/mmc-mxcmmc.h>
42 
43 #include <linux/platform_data/dma-imx.h>
44 
45 #define DRIVER_NAME "mxc-mmc"
46 #define MXCMCI_TIMEOUT_MS 10000
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 enum mxcmci_type {
116 	IMX21_MMC,
117 	IMX31_MMC,
118 };
119 
120 struct mxcmci_host {
121 	struct mmc_host		*mmc;
122 	struct resource		*res;
123 	void __iomem		*base;
124 	int			irq;
125 	int			detect_irq;
126 	struct dma_chan		*dma;
127 	struct dma_async_tx_descriptor *desc;
128 	int			do_dma;
129 	int			default_irq_mask;
130 	int			use_sdio;
131 	unsigned int		power_mode;
132 	struct imxmmc_platform_data *pdata;
133 
134 	struct mmc_request	*req;
135 	struct mmc_command	*cmd;
136 	struct mmc_data		*data;
137 
138 	unsigned int		datasize;
139 	unsigned int		dma_dir;
140 
141 	u16			rev_no;
142 	unsigned int		cmdat;
143 
144 	struct clk		*clk_ipg;
145 	struct clk		*clk_per;
146 
147 	int			clock;
148 
149 	struct work_struct	datawork;
150 	spinlock_t		lock;
151 
152 	struct regulator	*vcc;
153 
154 	int			burstlen;
155 	int			dmareq;
156 	struct dma_slave_config dma_slave_config;
157 	struct imx_dma_data	dma_data;
158 
159 	struct timer_list	watchdog;
160 	enum mxcmci_type	devtype;
161 };
162 
163 static struct platform_device_id mxcmci_devtype[] = {
164 	{
165 		.name = "imx21-mmc",
166 		.driver_data = IMX21_MMC,
167 	}, {
168 		.name = "imx31-mmc",
169 		.driver_data = IMX31_MMC,
170 	}, {
171 		/* sentinel */
172 	}
173 };
174 MODULE_DEVICE_TABLE(platform, mxcmci_devtype);
175 
176 static inline int is_imx31_mmc(struct mxcmci_host *host)
177 {
178 	return host->devtype == IMX31_MMC;
179 }
180 
181 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios);
182 
183 static inline void mxcmci_init_ocr(struct mxcmci_host *host)
184 {
185 	host->vcc = regulator_get(mmc_dev(host->mmc), "vmmc");
186 
187 	if (IS_ERR(host->vcc)) {
188 		host->vcc = NULL;
189 	} else {
190 		host->mmc->ocr_avail = mmc_regulator_get_ocrmask(host->vcc);
191 		if (host->pdata && host->pdata->ocr_avail)
192 			dev_warn(mmc_dev(host->mmc),
193 				"pdata->ocr_avail will not be used\n");
194 	}
195 
196 	if (host->vcc == NULL) {
197 		/* fall-back to platform data */
198 		if (host->pdata && host->pdata->ocr_avail)
199 			host->mmc->ocr_avail = host->pdata->ocr_avail;
200 		else
201 			host->mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
202 	}
203 }
204 
205 static inline void mxcmci_set_power(struct mxcmci_host *host,
206 				    unsigned char power_mode,
207 				    unsigned int vdd)
208 {
209 	if (host->vcc) {
210 		if (power_mode == MMC_POWER_UP)
211 			mmc_regulator_set_ocr(host->mmc, host->vcc, vdd);
212 		else if (power_mode == MMC_POWER_OFF)
213 			mmc_regulator_set_ocr(host->mmc, host->vcc, 0);
214 	}
215 
216 	if (host->pdata && host->pdata->setpower)
217 		host->pdata->setpower(mmc_dev(host->mmc), vdd);
218 }
219 
220 static inline int mxcmci_use_dma(struct mxcmci_host *host)
221 {
222 	return host->do_dma;
223 }
224 
225 static void mxcmci_softreset(struct mxcmci_host *host)
226 {
227 	int i;
228 
229 	dev_dbg(mmc_dev(host->mmc), "mxcmci_softreset\n");
230 
231 	/* reset sequence */
232 	writew(STR_STP_CLK_RESET, host->base + MMC_REG_STR_STP_CLK);
233 	writew(STR_STP_CLK_RESET | STR_STP_CLK_START_CLK,
234 			host->base + MMC_REG_STR_STP_CLK);
235 
236 	for (i = 0; i < 8; i++)
237 		writew(STR_STP_CLK_START_CLK, host->base + MMC_REG_STR_STP_CLK);
238 
239 	writew(0xff, host->base + MMC_REG_RES_TO);
240 }
241 static int mxcmci_setup_dma(struct mmc_host *mmc);
242 
243 static int mxcmci_setup_data(struct mxcmci_host *host, struct mmc_data *data)
244 {
245 	unsigned int nob = data->blocks;
246 	unsigned int blksz = data->blksz;
247 	unsigned int datasize = nob * blksz;
248 	struct scatterlist *sg;
249 	enum dma_transfer_direction slave_dirn;
250 	int i, nents;
251 
252 	if (data->flags & MMC_DATA_STREAM)
253 		nob = 0xffff;
254 
255 	host->data = data;
256 	data->bytes_xfered = 0;
257 
258 	writew(nob, host->base + MMC_REG_NOB);
259 	writew(blksz, host->base + MMC_REG_BLK_LEN);
260 	host->datasize = datasize;
261 
262 	if (!mxcmci_use_dma(host))
263 		return 0;
264 
265 	for_each_sg(data->sg, sg, data->sg_len, i) {
266 		if (sg->offset & 3 || sg->length & 3 || sg->length < 512) {
267 			host->do_dma = 0;
268 			return 0;
269 		}
270 	}
271 
272 	if (data->flags & MMC_DATA_READ) {
273 		host->dma_dir = DMA_FROM_DEVICE;
274 		slave_dirn = DMA_DEV_TO_MEM;
275 	} else {
276 		host->dma_dir = DMA_TO_DEVICE;
277 		slave_dirn = DMA_MEM_TO_DEV;
278 	}
279 
280 	nents = dma_map_sg(host->dma->device->dev, data->sg,
281 				     data->sg_len,  host->dma_dir);
282 	if (nents != data->sg_len)
283 		return -EINVAL;
284 
285 	host->desc = dmaengine_prep_slave_sg(host->dma,
286 		data->sg, data->sg_len, slave_dirn,
287 		DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
288 
289 	if (!host->desc) {
290 		dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
291 				host->dma_dir);
292 		host->do_dma = 0;
293 		return 0; /* Fall back to PIO */
294 	}
295 	wmb();
296 
297 	dmaengine_submit(host->desc);
298 	dma_async_issue_pending(host->dma);
299 
300 	mod_timer(&host->watchdog, jiffies + msecs_to_jiffies(MXCMCI_TIMEOUT_MS));
301 
302 	return 0;
303 }
304 
305 static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat);
306 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat);
307 
308 static void mxcmci_dma_callback(void *data)
309 {
310 	struct mxcmci_host *host = data;
311 	u32 stat;
312 
313 	del_timer(&host->watchdog);
314 
315 	stat = readl(host->base + MMC_REG_STATUS);
316 	writel(stat & ~STATUS_DATA_TRANS_DONE, host->base + MMC_REG_STATUS);
317 
318 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
319 
320 	if (stat & STATUS_READ_OP_DONE)
321 		writel(STATUS_READ_OP_DONE, host->base + MMC_REG_STATUS);
322 
323 	mxcmci_data_done(host, stat);
324 }
325 
326 static int mxcmci_start_cmd(struct mxcmci_host *host, struct mmc_command *cmd,
327 		unsigned int cmdat)
328 {
329 	u32 int_cntr = host->default_irq_mask;
330 	unsigned long flags;
331 
332 	WARN_ON(host->cmd != NULL);
333 	host->cmd = cmd;
334 
335 	switch (mmc_resp_type(cmd)) {
336 	case MMC_RSP_R1: /* short CRC, OPCODE */
337 	case MMC_RSP_R1B:/* short CRC, OPCODE, BUSY */
338 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT_CRC;
339 		break;
340 	case MMC_RSP_R2: /* long 136 bit + CRC */
341 		cmdat |= CMD_DAT_CONT_RESPONSE_136BIT;
342 		break;
343 	case MMC_RSP_R3: /* short */
344 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT;
345 		break;
346 	case MMC_RSP_NONE:
347 		break;
348 	default:
349 		dev_err(mmc_dev(host->mmc), "unhandled response type 0x%x\n",
350 				mmc_resp_type(cmd));
351 		cmd->error = -EINVAL;
352 		return -EINVAL;
353 	}
354 
355 	int_cntr = INT_END_CMD_RES_EN;
356 
357 	if (mxcmci_use_dma(host)) {
358 		if (host->dma_dir == DMA_FROM_DEVICE) {
359 			host->desc->callback = mxcmci_dma_callback;
360 			host->desc->callback_param = host;
361 		} else {
362 			int_cntr |= INT_WRITE_OP_DONE_EN;
363 		}
364 	}
365 
366 	spin_lock_irqsave(&host->lock, flags);
367 	if (host->use_sdio)
368 		int_cntr |= INT_SDIO_IRQ_EN;
369 	writel(int_cntr, host->base + MMC_REG_INT_CNTR);
370 	spin_unlock_irqrestore(&host->lock, flags);
371 
372 	writew(cmd->opcode, host->base + MMC_REG_CMD);
373 	writel(cmd->arg, host->base + MMC_REG_ARG);
374 	writew(cmdat, host->base + MMC_REG_CMD_DAT_CONT);
375 
376 	return 0;
377 }
378 
379 static void mxcmci_finish_request(struct mxcmci_host *host,
380 		struct mmc_request *req)
381 {
382 	u32 int_cntr = host->default_irq_mask;
383 	unsigned long flags;
384 
385 	spin_lock_irqsave(&host->lock, flags);
386 	if (host->use_sdio)
387 		int_cntr |= INT_SDIO_IRQ_EN;
388 	writel(int_cntr, host->base + MMC_REG_INT_CNTR);
389 	spin_unlock_irqrestore(&host->lock, flags);
390 
391 	host->req = NULL;
392 	host->cmd = NULL;
393 	host->data = NULL;
394 
395 	mmc_request_done(host->mmc, req);
396 }
397 
398 static int mxcmci_finish_data(struct mxcmci_host *host, unsigned int stat)
399 {
400 	struct mmc_data *data = host->data;
401 	int data_error;
402 
403 	if (mxcmci_use_dma(host))
404 		dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
405 				host->dma_dir);
406 
407 	if (stat & STATUS_ERR_MASK) {
408 		dev_dbg(mmc_dev(host->mmc), "request failed. status: 0x%08x\n",
409 				stat);
410 		if (stat & STATUS_CRC_READ_ERR) {
411 			dev_err(mmc_dev(host->mmc), "%s: -EILSEQ\n", __func__);
412 			data->error = -EILSEQ;
413 		} else if (stat & STATUS_CRC_WRITE_ERR) {
414 			u32 err_code = (stat >> 9) & 0x3;
415 			if (err_code == 2) { /* No CRC response */
416 				dev_err(mmc_dev(host->mmc),
417 					"%s: No CRC -ETIMEDOUT\n", __func__);
418 				data->error = -ETIMEDOUT;
419 			} else {
420 				dev_err(mmc_dev(host->mmc),
421 					"%s: -EILSEQ\n", __func__);
422 				data->error = -EILSEQ;
423 			}
424 		} else if (stat & STATUS_TIME_OUT_READ) {
425 			dev_err(mmc_dev(host->mmc),
426 				"%s: read -ETIMEDOUT\n", __func__);
427 			data->error = -ETIMEDOUT;
428 		} else {
429 			dev_err(mmc_dev(host->mmc), "%s: -EIO\n", __func__);
430 			data->error = -EIO;
431 		}
432 	} else {
433 		data->bytes_xfered = host->datasize;
434 	}
435 
436 	data_error = data->error;
437 
438 	host->data = NULL;
439 
440 	return data_error;
441 }
442 
443 static void mxcmci_read_response(struct mxcmci_host *host, unsigned int stat)
444 {
445 	struct mmc_command *cmd = host->cmd;
446 	int i;
447 	u32 a, b, c;
448 
449 	if (!cmd)
450 		return;
451 
452 	if (stat & STATUS_TIME_OUT_RESP) {
453 		dev_dbg(mmc_dev(host->mmc), "CMD TIMEOUT\n");
454 		cmd->error = -ETIMEDOUT;
455 	} else if (stat & STATUS_RESP_CRC_ERR && cmd->flags & MMC_RSP_CRC) {
456 		dev_dbg(mmc_dev(host->mmc), "cmd crc error\n");
457 		cmd->error = -EILSEQ;
458 	}
459 
460 	if (cmd->flags & MMC_RSP_PRESENT) {
461 		if (cmd->flags & MMC_RSP_136) {
462 			for (i = 0; i < 4; i++) {
463 				a = readw(host->base + MMC_REG_RES_FIFO);
464 				b = readw(host->base + MMC_REG_RES_FIFO);
465 				cmd->resp[i] = a << 16 | b;
466 			}
467 		} else {
468 			a = readw(host->base + MMC_REG_RES_FIFO);
469 			b = readw(host->base + MMC_REG_RES_FIFO);
470 			c = readw(host->base + MMC_REG_RES_FIFO);
471 			cmd->resp[0] = a << 24 | b << 8 | c >> 8;
472 		}
473 	}
474 }
475 
476 static int mxcmci_poll_status(struct mxcmci_host *host, u32 mask)
477 {
478 	u32 stat;
479 	unsigned long timeout = jiffies + HZ;
480 
481 	do {
482 		stat = readl(host->base + MMC_REG_STATUS);
483 		if (stat & STATUS_ERR_MASK)
484 			return stat;
485 		if (time_after(jiffies, timeout)) {
486 			mxcmci_softreset(host);
487 			mxcmci_set_clk_rate(host, host->clock);
488 			return STATUS_TIME_OUT_READ;
489 		}
490 		if (stat & mask)
491 			return 0;
492 		cpu_relax();
493 	} while (1);
494 }
495 
496 static int mxcmci_pull(struct mxcmci_host *host, void *_buf, int bytes)
497 {
498 	unsigned int stat;
499 	u32 *buf = _buf;
500 
501 	while (bytes > 3) {
502 		stat = mxcmci_poll_status(host,
503 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
504 		if (stat)
505 			return stat;
506 		*buf++ = readl(host->base + MMC_REG_BUFFER_ACCESS);
507 		bytes -= 4;
508 	}
509 
510 	if (bytes) {
511 		u8 *b = (u8 *)buf;
512 		u32 tmp;
513 
514 		stat = mxcmci_poll_status(host,
515 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
516 		if (stat)
517 			return stat;
518 		tmp = readl(host->base + MMC_REG_BUFFER_ACCESS);
519 		memcpy(b, &tmp, bytes);
520 	}
521 
522 	return 0;
523 }
524 
525 static int mxcmci_push(struct mxcmci_host *host, void *_buf, int bytes)
526 {
527 	unsigned int stat;
528 	u32 *buf = _buf;
529 
530 	while (bytes > 3) {
531 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
532 		if (stat)
533 			return stat;
534 		writel(*buf++, host->base + MMC_REG_BUFFER_ACCESS);
535 		bytes -= 4;
536 	}
537 
538 	if (bytes) {
539 		u8 *b = (u8 *)buf;
540 		u32 tmp;
541 
542 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
543 		if (stat)
544 			return stat;
545 
546 		memcpy(&tmp, b, bytes);
547 		writel(tmp, host->base + MMC_REG_BUFFER_ACCESS);
548 	}
549 
550 	stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
551 	if (stat)
552 		return stat;
553 
554 	return 0;
555 }
556 
557 static int mxcmci_transfer_data(struct mxcmci_host *host)
558 {
559 	struct mmc_data *data = host->req->data;
560 	struct scatterlist *sg;
561 	int stat, i;
562 
563 	host->data = data;
564 	host->datasize = 0;
565 
566 	if (data->flags & MMC_DATA_READ) {
567 		for_each_sg(data->sg, sg, data->sg_len, i) {
568 			stat = mxcmci_pull(host, sg_virt(sg), sg->length);
569 			if (stat)
570 				return stat;
571 			host->datasize += sg->length;
572 		}
573 	} else {
574 		for_each_sg(data->sg, sg, data->sg_len, i) {
575 			stat = mxcmci_push(host, sg_virt(sg), sg->length);
576 			if (stat)
577 				return stat;
578 			host->datasize += sg->length;
579 		}
580 		stat = mxcmci_poll_status(host, STATUS_WRITE_OP_DONE);
581 		if (stat)
582 			return stat;
583 	}
584 	return 0;
585 }
586 
587 static void mxcmci_datawork(struct work_struct *work)
588 {
589 	struct mxcmci_host *host = container_of(work, struct mxcmci_host,
590 						  datawork);
591 	int datastat = mxcmci_transfer_data(host);
592 
593 	writel(STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE,
594 		host->base + MMC_REG_STATUS);
595 	mxcmci_finish_data(host, datastat);
596 
597 	if (host->req->stop) {
598 		if (mxcmci_start_cmd(host, host->req->stop, 0)) {
599 			mxcmci_finish_request(host, host->req);
600 			return;
601 		}
602 	} else {
603 		mxcmci_finish_request(host, host->req);
604 	}
605 }
606 
607 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat)
608 {
609 	struct mmc_data *data = host->data;
610 	int data_error;
611 
612 	if (!data)
613 		return;
614 
615 	data_error = mxcmci_finish_data(host, stat);
616 
617 	mxcmci_read_response(host, stat);
618 	host->cmd = NULL;
619 
620 	if (host->req->stop) {
621 		if (mxcmci_start_cmd(host, host->req->stop, 0)) {
622 			mxcmci_finish_request(host, host->req);
623 			return;
624 		}
625 	} else {
626 		mxcmci_finish_request(host, host->req);
627 	}
628 }
629 
630 static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat)
631 {
632 	mxcmci_read_response(host, stat);
633 	host->cmd = NULL;
634 
635 	if (!host->data && host->req) {
636 		mxcmci_finish_request(host, host->req);
637 		return;
638 	}
639 
640 	/* For the DMA case the DMA engine handles the data transfer
641 	 * automatically. For non DMA we have to do it ourselves.
642 	 * Don't do it in interrupt context though.
643 	 */
644 	if (!mxcmci_use_dma(host) && host->data)
645 		schedule_work(&host->datawork);
646 
647 }
648 
649 static irqreturn_t mxcmci_irq(int irq, void *devid)
650 {
651 	struct mxcmci_host *host = devid;
652 	unsigned long flags;
653 	bool sdio_irq;
654 	u32 stat;
655 
656 	stat = readl(host->base + MMC_REG_STATUS);
657 	writel(stat & ~(STATUS_SDIO_INT_ACTIVE | STATUS_DATA_TRANS_DONE |
658 			STATUS_WRITE_OP_DONE), host->base + MMC_REG_STATUS);
659 
660 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
661 
662 	spin_lock_irqsave(&host->lock, flags);
663 	sdio_irq = (stat & STATUS_SDIO_INT_ACTIVE) && host->use_sdio;
664 	spin_unlock_irqrestore(&host->lock, flags);
665 
666 	if (mxcmci_use_dma(host) &&
667 	    (stat & (STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE)))
668 		writel(STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE,
669 			host->base + MMC_REG_STATUS);
670 
671 	if (sdio_irq) {
672 		writel(STATUS_SDIO_INT_ACTIVE, host->base + MMC_REG_STATUS);
673 		mmc_signal_sdio_irq(host->mmc);
674 	}
675 
676 	if (stat & STATUS_END_CMD_RESP)
677 		mxcmci_cmd_done(host, stat);
678 
679 	if (mxcmci_use_dma(host) &&
680 		  (stat & (STATUS_DATA_TRANS_DONE | STATUS_WRITE_OP_DONE))) {
681 		del_timer(&host->watchdog);
682 		mxcmci_data_done(host, stat);
683 	}
684 
685 	if (host->default_irq_mask &&
686 		  (stat & (STATUS_CARD_INSERTION | STATUS_CARD_REMOVAL)))
687 		mmc_detect_change(host->mmc, msecs_to_jiffies(200));
688 
689 	return IRQ_HANDLED;
690 }
691 
692 static void mxcmci_request(struct mmc_host *mmc, struct mmc_request *req)
693 {
694 	struct mxcmci_host *host = mmc_priv(mmc);
695 	unsigned int cmdat = host->cmdat;
696 	int error;
697 
698 	WARN_ON(host->req != NULL);
699 
700 	host->req = req;
701 	host->cmdat &= ~CMD_DAT_CONT_INIT;
702 
703 	if (host->dma)
704 		host->do_dma = 1;
705 
706 	if (req->data) {
707 		error = mxcmci_setup_data(host, req->data);
708 		if (error) {
709 			req->cmd->error = error;
710 			goto out;
711 		}
712 
713 
714 		cmdat |= CMD_DAT_CONT_DATA_ENABLE;
715 
716 		if (req->data->flags & MMC_DATA_WRITE)
717 			cmdat |= CMD_DAT_CONT_WRITE;
718 	}
719 
720 	error = mxcmci_start_cmd(host, req->cmd, cmdat);
721 
722 out:
723 	if (error)
724 		mxcmci_finish_request(host, req);
725 }
726 
727 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios)
728 {
729 	unsigned int divider;
730 	int prescaler = 0;
731 	unsigned int clk_in = clk_get_rate(host->clk_per);
732 
733 	while (prescaler <= 0x800) {
734 		for (divider = 1; divider <= 0xF; divider++) {
735 			int x;
736 
737 			x = (clk_in / (divider + 1));
738 
739 			if (prescaler)
740 				x /= (prescaler * 2);
741 
742 			if (x <= clk_ios)
743 				break;
744 		}
745 		if (divider < 0x10)
746 			break;
747 
748 		if (prescaler == 0)
749 			prescaler = 1;
750 		else
751 			prescaler <<= 1;
752 	}
753 
754 	writew((prescaler << 4) | divider, host->base + MMC_REG_CLK_RATE);
755 
756 	dev_dbg(mmc_dev(host->mmc), "scaler: %d divider: %d in: %d out: %d\n",
757 			prescaler, divider, clk_in, clk_ios);
758 }
759 
760 static int mxcmci_setup_dma(struct mmc_host *mmc)
761 {
762 	struct mxcmci_host *host = mmc_priv(mmc);
763 	struct dma_slave_config *config = &host->dma_slave_config;
764 
765 	config->dst_addr = host->res->start + MMC_REG_BUFFER_ACCESS;
766 	config->src_addr = host->res->start + MMC_REG_BUFFER_ACCESS;
767 	config->dst_addr_width = 4;
768 	config->src_addr_width = 4;
769 	config->dst_maxburst = host->burstlen;
770 	config->src_maxburst = host->burstlen;
771 	config->device_fc = false;
772 
773 	return dmaengine_slave_config(host->dma, config);
774 }
775 
776 static void mxcmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
777 {
778 	struct mxcmci_host *host = mmc_priv(mmc);
779 	int burstlen, ret;
780 
781 	/*
782 	 * use burstlen of 64 (16 words) in 4 bit mode (--> reg value  0)
783 	 * use burstlen of 16 (4 words) in 1 bit mode (--> reg value 16)
784 	 */
785 	if (ios->bus_width == MMC_BUS_WIDTH_4)
786 		burstlen = 16;
787 	else
788 		burstlen = 4;
789 
790 	if (mxcmci_use_dma(host) && burstlen != host->burstlen) {
791 		host->burstlen = burstlen;
792 		ret = mxcmci_setup_dma(mmc);
793 		if (ret) {
794 			dev_err(mmc_dev(host->mmc),
795 				"failed to config DMA channel. Falling back to PIO\n");
796 			dma_release_channel(host->dma);
797 			host->do_dma = 0;
798 			host->dma = NULL;
799 		}
800 	}
801 
802 	if (ios->bus_width == MMC_BUS_WIDTH_4)
803 		host->cmdat |= CMD_DAT_CONT_BUS_WIDTH_4;
804 	else
805 		host->cmdat &= ~CMD_DAT_CONT_BUS_WIDTH_4;
806 
807 	if (host->power_mode != ios->power_mode) {
808 		mxcmci_set_power(host, ios->power_mode, ios->vdd);
809 		host->power_mode = ios->power_mode;
810 
811 		if (ios->power_mode == MMC_POWER_ON)
812 			host->cmdat |= CMD_DAT_CONT_INIT;
813 	}
814 
815 	if (ios->clock) {
816 		mxcmci_set_clk_rate(host, ios->clock);
817 		writew(STR_STP_CLK_START_CLK, host->base + MMC_REG_STR_STP_CLK);
818 	} else {
819 		writew(STR_STP_CLK_STOP_CLK, host->base + MMC_REG_STR_STP_CLK);
820 	}
821 
822 	host->clock = ios->clock;
823 }
824 
825 static irqreturn_t mxcmci_detect_irq(int irq, void *data)
826 {
827 	struct mmc_host *mmc = data;
828 
829 	dev_dbg(mmc_dev(mmc), "%s\n", __func__);
830 
831 	mmc_detect_change(mmc, msecs_to_jiffies(250));
832 	return IRQ_HANDLED;
833 }
834 
835 static int mxcmci_get_ro(struct mmc_host *mmc)
836 {
837 	struct mxcmci_host *host = mmc_priv(mmc);
838 
839 	if (host->pdata && host->pdata->get_ro)
840 		return !!host->pdata->get_ro(mmc_dev(mmc));
841 	/*
842 	 * Board doesn't support read only detection; let the mmc core
843 	 * decide what to do.
844 	 */
845 	return -ENOSYS;
846 }
847 
848 static void mxcmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
849 {
850 	struct mxcmci_host *host = mmc_priv(mmc);
851 	unsigned long flags;
852 	u32 int_cntr;
853 
854 	spin_lock_irqsave(&host->lock, flags);
855 	host->use_sdio = enable;
856 	int_cntr = readl(host->base + MMC_REG_INT_CNTR);
857 
858 	if (enable)
859 		int_cntr |= INT_SDIO_IRQ_EN;
860 	else
861 		int_cntr &= ~INT_SDIO_IRQ_EN;
862 
863 	writel(int_cntr, host->base + MMC_REG_INT_CNTR);
864 	spin_unlock_irqrestore(&host->lock, flags);
865 }
866 
867 static void mxcmci_init_card(struct mmc_host *host, struct mmc_card *card)
868 {
869 	struct mxcmci_host *mxcmci = mmc_priv(host);
870 
871 	/*
872 	 * MX3 SoCs have a silicon bug which corrupts CRC calculation of
873 	 * multi-block transfers when connected SDIO peripheral doesn't
874 	 * drive the BUSY line as required by the specs.
875 	 * One way to prevent this is to only allow 1-bit transfers.
876 	 */
877 
878 	if (is_imx31_mmc(mxcmci) && card->type == MMC_TYPE_SDIO)
879 		host->caps &= ~MMC_CAP_4_BIT_DATA;
880 	else
881 		host->caps |= MMC_CAP_4_BIT_DATA;
882 }
883 
884 static bool filter(struct dma_chan *chan, void *param)
885 {
886 	struct mxcmci_host *host = param;
887 
888 	if (!imx_dma_is_general_purpose(chan))
889 		return false;
890 
891 	chan->private = &host->dma_data;
892 
893 	return true;
894 }
895 
896 static void mxcmci_watchdog(unsigned long data)
897 {
898 	struct mmc_host *mmc = (struct mmc_host *)data;
899 	struct mxcmci_host *host = mmc_priv(mmc);
900 	struct mmc_request *req = host->req;
901 	unsigned int stat = readl(host->base + MMC_REG_STATUS);
902 
903 	if (host->dma_dir == DMA_FROM_DEVICE) {
904 		dmaengine_terminate_all(host->dma);
905 		dev_err(mmc_dev(host->mmc),
906 			"%s: read time out (status = 0x%08x)\n",
907 			__func__, stat);
908 	} else {
909 		dev_err(mmc_dev(host->mmc),
910 			"%s: write time out (status = 0x%08x)\n",
911 			__func__, stat);
912 		mxcmci_softreset(host);
913 	}
914 
915 	/* Mark transfer as erroneus and inform the upper layers */
916 
917 	host->data->error = -ETIMEDOUT;
918 	host->req = NULL;
919 	host->cmd = NULL;
920 	host->data = NULL;
921 	mmc_request_done(host->mmc, req);
922 }
923 
924 static const struct mmc_host_ops mxcmci_ops = {
925 	.request		= mxcmci_request,
926 	.set_ios		= mxcmci_set_ios,
927 	.get_ro			= mxcmci_get_ro,
928 	.enable_sdio_irq	= mxcmci_enable_sdio_irq,
929 	.init_card		= mxcmci_init_card,
930 };
931 
932 static int mxcmci_probe(struct platform_device *pdev)
933 {
934 	struct mmc_host *mmc;
935 	struct mxcmci_host *host = NULL;
936 	struct resource *iores, *r;
937 	int ret = 0, irq;
938 	dma_cap_mask_t mask;
939 
940 	pr_info("i.MX SDHC driver\n");
941 
942 	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
943 	irq = platform_get_irq(pdev, 0);
944 	if (!iores || irq < 0)
945 		return -EINVAL;
946 
947 	r = request_mem_region(iores->start, resource_size(iores), pdev->name);
948 	if (!r)
949 		return -EBUSY;
950 
951 	mmc = mmc_alloc_host(sizeof(struct mxcmci_host), &pdev->dev);
952 	if (!mmc) {
953 		ret = -ENOMEM;
954 		goto out_release_mem;
955 	}
956 
957 	mmc->ops = &mxcmci_ops;
958 	mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
959 
960 	/* MMC core transfer sizes tunable parameters */
961 	mmc->max_segs = 64;
962 	mmc->max_blk_size = 2048;
963 	mmc->max_blk_count = 65535;
964 	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
965 	mmc->max_seg_size = mmc->max_req_size;
966 
967 	host = mmc_priv(mmc);
968 	host->base = ioremap(r->start, resource_size(r));
969 	if (!host->base) {
970 		ret = -ENOMEM;
971 		goto out_free;
972 	}
973 
974 	host->mmc = mmc;
975 	host->pdata = pdev->dev.platform_data;
976 	host->devtype = pdev->id_entry->driver_data;
977 	spin_lock_init(&host->lock);
978 
979 	mxcmci_init_ocr(host);
980 
981 	if (host->pdata && host->pdata->dat3_card_detect)
982 		host->default_irq_mask =
983 			INT_CARD_INSERTION_EN | INT_CARD_REMOVAL_EN;
984 	else
985 		host->default_irq_mask = 0;
986 
987 	host->res = r;
988 	host->irq = irq;
989 
990 	host->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
991 	if (IS_ERR(host->clk_ipg)) {
992 		ret = PTR_ERR(host->clk_ipg);
993 		goto out_iounmap;
994 	}
995 
996 	host->clk_per = devm_clk_get(&pdev->dev, "per");
997 	if (IS_ERR(host->clk_per)) {
998 		ret = PTR_ERR(host->clk_per);
999 		goto out_iounmap;
1000 	}
1001 
1002 	clk_prepare_enable(host->clk_per);
1003 	clk_prepare_enable(host->clk_ipg);
1004 
1005 	mxcmci_softreset(host);
1006 
1007 	host->rev_no = readw(host->base + MMC_REG_REV_NO);
1008 	if (host->rev_no != 0x400) {
1009 		ret = -ENODEV;
1010 		dev_err(mmc_dev(host->mmc), "wrong rev.no. 0x%08x. aborting.\n",
1011 			host->rev_no);
1012 		goto out_clk_put;
1013 	}
1014 
1015 	mmc->f_min = clk_get_rate(host->clk_per) >> 16;
1016 	mmc->f_max = clk_get_rate(host->clk_per) >> 1;
1017 
1018 	/* recommended in data sheet */
1019 	writew(0x2db4, host->base + MMC_REG_READ_TO);
1020 
1021 	writel(host->default_irq_mask, host->base + MMC_REG_INT_CNTR);
1022 
1023 	r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1024 	if (r) {
1025 		host->dmareq = r->start;
1026 		host->dma_data.peripheral_type = IMX_DMATYPE_SDHC;
1027 		host->dma_data.priority = DMA_PRIO_LOW;
1028 		host->dma_data.dma_request = host->dmareq;
1029 		dma_cap_zero(mask);
1030 		dma_cap_set(DMA_SLAVE, mask);
1031 		host->dma = dma_request_channel(mask, filter, host);
1032 		if (host->dma)
1033 			mmc->max_seg_size = dma_get_max_seg_size(
1034 					host->dma->device->dev);
1035 	}
1036 
1037 	if (!host->dma)
1038 		dev_info(mmc_dev(host->mmc), "dma not available. Using PIO\n");
1039 
1040 	INIT_WORK(&host->datawork, mxcmci_datawork);
1041 
1042 	ret = request_irq(host->irq, mxcmci_irq, 0, DRIVER_NAME, host);
1043 	if (ret)
1044 		goto out_free_dma;
1045 
1046 	platform_set_drvdata(pdev, mmc);
1047 
1048 	if (host->pdata && host->pdata->init) {
1049 		ret = host->pdata->init(&pdev->dev, mxcmci_detect_irq,
1050 				host->mmc);
1051 		if (ret)
1052 			goto out_free_irq;
1053 	}
1054 
1055 	mmc_add_host(mmc);
1056 
1057 	init_timer(&host->watchdog);
1058 	host->watchdog.function = &mxcmci_watchdog;
1059 	host->watchdog.data = (unsigned long)mmc;
1060 
1061 	return 0;
1062 
1063 out_free_irq:
1064 	free_irq(host->irq, host);
1065 out_free_dma:
1066 	if (host->dma)
1067 		dma_release_channel(host->dma);
1068 out_clk_put:
1069 	clk_disable_unprepare(host->clk_per);
1070 	clk_disable_unprepare(host->clk_ipg);
1071 out_iounmap:
1072 	iounmap(host->base);
1073 out_free:
1074 	mmc_free_host(mmc);
1075 out_release_mem:
1076 	release_mem_region(iores->start, resource_size(iores));
1077 	return ret;
1078 }
1079 
1080 static int mxcmci_remove(struct platform_device *pdev)
1081 {
1082 	struct mmc_host *mmc = platform_get_drvdata(pdev);
1083 	struct mxcmci_host *host = mmc_priv(mmc);
1084 
1085 	platform_set_drvdata(pdev, NULL);
1086 
1087 	mmc_remove_host(mmc);
1088 
1089 	if (host->vcc)
1090 		regulator_put(host->vcc);
1091 
1092 	if (host->pdata && host->pdata->exit)
1093 		host->pdata->exit(&pdev->dev, mmc);
1094 
1095 	free_irq(host->irq, host);
1096 	iounmap(host->base);
1097 
1098 	if (host->dma)
1099 		dma_release_channel(host->dma);
1100 
1101 	clk_disable_unprepare(host->clk_per);
1102 	clk_disable_unprepare(host->clk_ipg);
1103 
1104 	release_mem_region(host->res->start, resource_size(host->res));
1105 
1106 	mmc_free_host(mmc);
1107 
1108 	return 0;
1109 }
1110 
1111 #ifdef CONFIG_PM
1112 static int mxcmci_suspend(struct device *dev)
1113 {
1114 	struct mmc_host *mmc = dev_get_drvdata(dev);
1115 	struct mxcmci_host *host = mmc_priv(mmc);
1116 	int ret = 0;
1117 
1118 	if (mmc)
1119 		ret = mmc_suspend_host(mmc);
1120 	clk_disable_unprepare(host->clk_per);
1121 	clk_disable_unprepare(host->clk_ipg);
1122 
1123 	return ret;
1124 }
1125 
1126 static int mxcmci_resume(struct device *dev)
1127 {
1128 	struct mmc_host *mmc = dev_get_drvdata(dev);
1129 	struct mxcmci_host *host = mmc_priv(mmc);
1130 	int ret = 0;
1131 
1132 	clk_prepare_enable(host->clk_per);
1133 	clk_prepare_enable(host->clk_ipg);
1134 	if (mmc)
1135 		ret = mmc_resume_host(mmc);
1136 
1137 	return ret;
1138 }
1139 
1140 static const struct dev_pm_ops mxcmci_pm_ops = {
1141 	.suspend	= mxcmci_suspend,
1142 	.resume		= mxcmci_resume,
1143 };
1144 #endif
1145 
1146 static struct platform_driver mxcmci_driver = {
1147 	.probe		= mxcmci_probe,
1148 	.remove		= mxcmci_remove,
1149 	.id_table	= mxcmci_devtype,
1150 	.driver		= {
1151 		.name		= DRIVER_NAME,
1152 		.owner		= THIS_MODULE,
1153 #ifdef CONFIG_PM
1154 		.pm	= &mxcmci_pm_ops,
1155 #endif
1156 	}
1157 };
1158 
1159 module_platform_driver(mxcmci_driver);
1160 
1161 MODULE_DESCRIPTION("i.MX Multimedia Card Interface Driver");
1162 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1163 MODULE_LICENSE("GPL");
1164 MODULE_ALIAS("platform:mxc-mmc");
1165