xref: /linux/drivers/mmc/host/mxcmmc.c (revision 22d55f02b8922a097cd4be1e2f131dfa7ef65901)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/drivers/mmc/host/mxcmmc.c - Freescale i.MX MMCI driver
4  *
5  *  This is a driver for the SDHC controller found in Freescale MX2/MX3
6  *  SoCs. It is basically the same hardware as found on MX1 (imxmmc.c).
7  *  Unlike the hardware found on MX1, this hardware just works and does
8  *  not need all the quirks found in imxmmc.c, hence the separate driver.
9  *
10  *  Copyright (C) 2008 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
11  *  Copyright (C) 2006 Pavel Pisa, PiKRON <ppisa@pikron.com>
12  *
13  *  derived from pxamci.c by Russell King
14  */
15 
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/ioport.h>
19 #include <linux/platform_device.h>
20 #include <linux/highmem.h>
21 #include <linux/interrupt.h>
22 #include <linux/irq.h>
23 #include <linux/blkdev.h>
24 #include <linux/dma-mapping.h>
25 #include <linux/mmc/host.h>
26 #include <linux/mmc/card.h>
27 #include <linux/delay.h>
28 #include <linux/clk.h>
29 #include <linux/io.h>
30 #include <linux/regulator/consumer.h>
31 #include <linux/dmaengine.h>
32 #include <linux/types.h>
33 #include <linux/of.h>
34 #include <linux/of_device.h>
35 #include <linux/of_dma.h>
36 #include <linux/mmc/slot-gpio.h>
37 
38 #include <asm/dma.h>
39 #include <asm/irq.h>
40 #include <linux/platform_data/mmc-mxcmmc.h>
41 
42 #include <linux/platform_data/dma-imx.h>
43 
44 #define DRIVER_NAME "mxc-mmc"
45 #define MXCMCI_TIMEOUT_MS 10000
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 enum mxcmci_type {
115 	IMX21_MMC,
116 	IMX31_MMC,
117 	MPC512X_MMC,
118 };
119 
120 struct mxcmci_host {
121 	struct mmc_host		*mmc;
122 	void __iomem		*base;
123 	dma_addr_t		phys_base;
124 	int			detect_irq;
125 	struct dma_chan		*dma;
126 	struct dma_async_tx_descriptor *desc;
127 	int			do_dma;
128 	int			default_irq_mask;
129 	int			use_sdio;
130 	unsigned int		power_mode;
131 	struct imxmmc_platform_data *pdata;
132 
133 	struct mmc_request	*req;
134 	struct mmc_command	*cmd;
135 	struct mmc_data		*data;
136 
137 	unsigned int		datasize;
138 	unsigned int		dma_dir;
139 
140 	u16			rev_no;
141 	unsigned int		cmdat;
142 
143 	struct clk		*clk_ipg;
144 	struct clk		*clk_per;
145 
146 	int			clock;
147 
148 	struct work_struct	datawork;
149 	spinlock_t		lock;
150 
151 	int			burstlen;
152 	int			dmareq;
153 	struct dma_slave_config dma_slave_config;
154 	struct imx_dma_data	dma_data;
155 
156 	struct timer_list	watchdog;
157 	enum mxcmci_type	devtype;
158 };
159 
160 static const struct platform_device_id mxcmci_devtype[] = {
161 	{
162 		.name = "imx21-mmc",
163 		.driver_data = IMX21_MMC,
164 	}, {
165 		.name = "imx31-mmc",
166 		.driver_data = IMX31_MMC,
167 	}, {
168 		.name = "mpc512x-sdhc",
169 		.driver_data = MPC512X_MMC,
170 	}, {
171 		/* sentinel */
172 	}
173 };
174 MODULE_DEVICE_TABLE(platform, mxcmci_devtype);
175 
176 static const struct of_device_id mxcmci_of_match[] = {
177 	{
178 		.compatible = "fsl,imx21-mmc",
179 		.data = &mxcmci_devtype[IMX21_MMC],
180 	}, {
181 		.compatible = "fsl,imx31-mmc",
182 		.data = &mxcmci_devtype[IMX31_MMC],
183 	}, {
184 		.compatible = "fsl,mpc5121-sdhc",
185 		.data = &mxcmci_devtype[MPC512X_MMC],
186 	}, {
187 		/* sentinel */
188 	}
189 };
190 MODULE_DEVICE_TABLE(of, mxcmci_of_match);
191 
192 static inline int is_imx31_mmc(struct mxcmci_host *host)
193 {
194 	return host->devtype == IMX31_MMC;
195 }
196 
197 static inline int is_mpc512x_mmc(struct mxcmci_host *host)
198 {
199 	return host->devtype == MPC512X_MMC;
200 }
201 
202 static inline u32 mxcmci_readl(struct mxcmci_host *host, int reg)
203 {
204 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
205 		return ioread32be(host->base + reg);
206 	else
207 		return readl(host->base + reg);
208 }
209 
210 static inline void mxcmci_writel(struct mxcmci_host *host, u32 val, int reg)
211 {
212 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
213 		iowrite32be(val, host->base + reg);
214 	else
215 		writel(val, host->base + reg);
216 }
217 
218 static inline u16 mxcmci_readw(struct mxcmci_host *host, int reg)
219 {
220 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
221 		return ioread32be(host->base + reg);
222 	else
223 		return readw(host->base + reg);
224 }
225 
226 static inline void mxcmci_writew(struct mxcmci_host *host, u16 val, int reg)
227 {
228 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
229 		iowrite32be(val, host->base + reg);
230 	else
231 		writew(val, host->base + reg);
232 }
233 
234 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios);
235 
236 static void mxcmci_set_power(struct mxcmci_host *host, unsigned int vdd)
237 {
238 	if (!IS_ERR(host->mmc->supply.vmmc)) {
239 		if (host->power_mode == MMC_POWER_UP)
240 			mmc_regulator_set_ocr(host->mmc,
241 					      host->mmc->supply.vmmc, vdd);
242 		else if (host->power_mode == MMC_POWER_OFF)
243 			mmc_regulator_set_ocr(host->mmc,
244 					      host->mmc->supply.vmmc, 0);
245 	}
246 
247 	if (host->pdata && host->pdata->setpower)
248 		host->pdata->setpower(mmc_dev(host->mmc), vdd);
249 }
250 
251 static inline int mxcmci_use_dma(struct mxcmci_host *host)
252 {
253 	return host->do_dma;
254 }
255 
256 static void mxcmci_softreset(struct mxcmci_host *host)
257 {
258 	int i;
259 
260 	dev_dbg(mmc_dev(host->mmc), "mxcmci_softreset\n");
261 
262 	/* reset sequence */
263 	mxcmci_writew(host, STR_STP_CLK_RESET, MMC_REG_STR_STP_CLK);
264 	mxcmci_writew(host, STR_STP_CLK_RESET | STR_STP_CLK_START_CLK,
265 			MMC_REG_STR_STP_CLK);
266 
267 	for (i = 0; i < 8; i++)
268 		mxcmci_writew(host, STR_STP_CLK_START_CLK, MMC_REG_STR_STP_CLK);
269 
270 	mxcmci_writew(host, 0xff, MMC_REG_RES_TO);
271 }
272 
273 #if IS_ENABLED(CONFIG_PPC_MPC512x)
274 static inline void buffer_swap32(u32 *buf, int len)
275 {
276 	int i;
277 
278 	for (i = 0; i < ((len + 3) / 4); i++) {
279 		*buf = swab32(*buf);
280 		buf++;
281 	}
282 }
283 
284 static void mxcmci_swap_buffers(struct mmc_data *data)
285 {
286 	struct scatterlist *sg;
287 	int i;
288 
289 	for_each_sg(data->sg, sg, data->sg_len, i)
290 		buffer_swap32(sg_virt(sg), sg->length);
291 }
292 #else
293 static inline void mxcmci_swap_buffers(struct mmc_data *data) {}
294 #endif
295 
296 static int mxcmci_setup_data(struct mxcmci_host *host, struct mmc_data *data)
297 {
298 	unsigned int nob = data->blocks;
299 	unsigned int blksz = data->blksz;
300 	unsigned int datasize = nob * blksz;
301 	struct scatterlist *sg;
302 	enum dma_transfer_direction slave_dirn;
303 	int i, nents;
304 
305 	host->data = data;
306 	data->bytes_xfered = 0;
307 
308 	mxcmci_writew(host, nob, MMC_REG_NOB);
309 	mxcmci_writew(host, blksz, MMC_REG_BLK_LEN);
310 	host->datasize = datasize;
311 
312 	if (!mxcmci_use_dma(host))
313 		return 0;
314 
315 	for_each_sg(data->sg, sg, data->sg_len, i) {
316 		if (sg->offset & 3 || sg->length & 3 || sg->length < 512) {
317 			host->do_dma = 0;
318 			return 0;
319 		}
320 	}
321 
322 	if (data->flags & MMC_DATA_READ) {
323 		host->dma_dir = DMA_FROM_DEVICE;
324 		slave_dirn = DMA_DEV_TO_MEM;
325 	} else {
326 		host->dma_dir = DMA_TO_DEVICE;
327 		slave_dirn = DMA_MEM_TO_DEV;
328 
329 		mxcmci_swap_buffers(data);
330 	}
331 
332 	nents = dma_map_sg(host->dma->device->dev, data->sg,
333 				     data->sg_len,  host->dma_dir);
334 	if (nents != data->sg_len)
335 		return -EINVAL;
336 
337 	host->desc = dmaengine_prep_slave_sg(host->dma,
338 		data->sg, data->sg_len, slave_dirn,
339 		DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
340 
341 	if (!host->desc) {
342 		dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
343 				host->dma_dir);
344 		host->do_dma = 0;
345 		return 0; /* Fall back to PIO */
346 	}
347 	wmb();
348 
349 	dmaengine_submit(host->desc);
350 	dma_async_issue_pending(host->dma);
351 
352 	mod_timer(&host->watchdog, jiffies + msecs_to_jiffies(MXCMCI_TIMEOUT_MS));
353 
354 	return 0;
355 }
356 
357 static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat);
358 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat);
359 
360 static void mxcmci_dma_callback(void *data)
361 {
362 	struct mxcmci_host *host = data;
363 	u32 stat;
364 
365 	del_timer(&host->watchdog);
366 
367 	stat = mxcmci_readl(host, MMC_REG_STATUS);
368 
369 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
370 
371 	mxcmci_data_done(host, stat);
372 }
373 
374 static int mxcmci_start_cmd(struct mxcmci_host *host, struct mmc_command *cmd,
375 		unsigned int cmdat)
376 {
377 	u32 int_cntr = host->default_irq_mask;
378 	unsigned long flags;
379 
380 	WARN_ON(host->cmd != NULL);
381 	host->cmd = cmd;
382 
383 	switch (mmc_resp_type(cmd)) {
384 	case MMC_RSP_R1: /* short CRC, OPCODE */
385 	case MMC_RSP_R1B:/* short CRC, OPCODE, BUSY */
386 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT_CRC;
387 		break;
388 	case MMC_RSP_R2: /* long 136 bit + CRC */
389 		cmdat |= CMD_DAT_CONT_RESPONSE_136BIT;
390 		break;
391 	case MMC_RSP_R3: /* short */
392 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT;
393 		break;
394 	case MMC_RSP_NONE:
395 		break;
396 	default:
397 		dev_err(mmc_dev(host->mmc), "unhandled response type 0x%x\n",
398 				mmc_resp_type(cmd));
399 		cmd->error = -EINVAL;
400 		return -EINVAL;
401 	}
402 
403 	int_cntr = INT_END_CMD_RES_EN;
404 
405 	if (mxcmci_use_dma(host)) {
406 		if (host->dma_dir == DMA_FROM_DEVICE) {
407 			host->desc->callback = mxcmci_dma_callback;
408 			host->desc->callback_param = host;
409 		} else {
410 			int_cntr |= INT_WRITE_OP_DONE_EN;
411 		}
412 	}
413 
414 	spin_lock_irqsave(&host->lock, flags);
415 	if (host->use_sdio)
416 		int_cntr |= INT_SDIO_IRQ_EN;
417 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
418 	spin_unlock_irqrestore(&host->lock, flags);
419 
420 	mxcmci_writew(host, cmd->opcode, MMC_REG_CMD);
421 	mxcmci_writel(host, cmd->arg, MMC_REG_ARG);
422 	mxcmci_writew(host, cmdat, MMC_REG_CMD_DAT_CONT);
423 
424 	return 0;
425 }
426 
427 static void mxcmci_finish_request(struct mxcmci_host *host,
428 		struct mmc_request *req)
429 {
430 	u32 int_cntr = host->default_irq_mask;
431 	unsigned long flags;
432 
433 	spin_lock_irqsave(&host->lock, flags);
434 	if (host->use_sdio)
435 		int_cntr |= INT_SDIO_IRQ_EN;
436 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
437 	spin_unlock_irqrestore(&host->lock, flags);
438 
439 	host->req = NULL;
440 	host->cmd = NULL;
441 	host->data = NULL;
442 
443 	mmc_request_done(host->mmc, req);
444 }
445 
446 static int mxcmci_finish_data(struct mxcmci_host *host, unsigned int stat)
447 {
448 	struct mmc_data *data = host->data;
449 	int data_error;
450 
451 	if (mxcmci_use_dma(host)) {
452 		dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
453 				host->dma_dir);
454 		mxcmci_swap_buffers(data);
455 	}
456 
457 	if (stat & STATUS_ERR_MASK) {
458 		dev_dbg(mmc_dev(host->mmc), "request failed. status: 0x%08x\n",
459 				stat);
460 		if (stat & STATUS_CRC_READ_ERR) {
461 			dev_err(mmc_dev(host->mmc), "%s: -EILSEQ\n", __func__);
462 			data->error = -EILSEQ;
463 		} else if (stat & STATUS_CRC_WRITE_ERR) {
464 			u32 err_code = (stat >> 9) & 0x3;
465 			if (err_code == 2) { /* No CRC response */
466 				dev_err(mmc_dev(host->mmc),
467 					"%s: No CRC -ETIMEDOUT\n", __func__);
468 				data->error = -ETIMEDOUT;
469 			} else {
470 				dev_err(mmc_dev(host->mmc),
471 					"%s: -EILSEQ\n", __func__);
472 				data->error = -EILSEQ;
473 			}
474 		} else if (stat & STATUS_TIME_OUT_READ) {
475 			dev_err(mmc_dev(host->mmc),
476 				"%s: read -ETIMEDOUT\n", __func__);
477 			data->error = -ETIMEDOUT;
478 		} else {
479 			dev_err(mmc_dev(host->mmc), "%s: -EIO\n", __func__);
480 			data->error = -EIO;
481 		}
482 	} else {
483 		data->bytes_xfered = host->datasize;
484 	}
485 
486 	data_error = data->error;
487 
488 	host->data = NULL;
489 
490 	return data_error;
491 }
492 
493 static void mxcmci_read_response(struct mxcmci_host *host, unsigned int stat)
494 {
495 	struct mmc_command *cmd = host->cmd;
496 	int i;
497 	u32 a, b, c;
498 
499 	if (!cmd)
500 		return;
501 
502 	if (stat & STATUS_TIME_OUT_RESP) {
503 		dev_dbg(mmc_dev(host->mmc), "CMD TIMEOUT\n");
504 		cmd->error = -ETIMEDOUT;
505 	} else if (stat & STATUS_RESP_CRC_ERR && cmd->flags & MMC_RSP_CRC) {
506 		dev_dbg(mmc_dev(host->mmc), "cmd crc error\n");
507 		cmd->error = -EILSEQ;
508 	}
509 
510 	if (cmd->flags & MMC_RSP_PRESENT) {
511 		if (cmd->flags & MMC_RSP_136) {
512 			for (i = 0; i < 4; i++) {
513 				a = mxcmci_readw(host, MMC_REG_RES_FIFO);
514 				b = mxcmci_readw(host, MMC_REG_RES_FIFO);
515 				cmd->resp[i] = a << 16 | b;
516 			}
517 		} else {
518 			a = mxcmci_readw(host, MMC_REG_RES_FIFO);
519 			b = mxcmci_readw(host, MMC_REG_RES_FIFO);
520 			c = mxcmci_readw(host, MMC_REG_RES_FIFO);
521 			cmd->resp[0] = a << 24 | b << 8 | c >> 8;
522 		}
523 	}
524 }
525 
526 static int mxcmci_poll_status(struct mxcmci_host *host, u32 mask)
527 {
528 	u32 stat;
529 	unsigned long timeout = jiffies + HZ;
530 
531 	do {
532 		stat = mxcmci_readl(host, MMC_REG_STATUS);
533 		if (stat & STATUS_ERR_MASK)
534 			return stat;
535 		if (time_after(jiffies, timeout)) {
536 			mxcmci_softreset(host);
537 			mxcmci_set_clk_rate(host, host->clock);
538 			return STATUS_TIME_OUT_READ;
539 		}
540 		if (stat & mask)
541 			return 0;
542 		cpu_relax();
543 	} while (1);
544 }
545 
546 static int mxcmci_pull(struct mxcmci_host *host, void *_buf, int bytes)
547 {
548 	unsigned int stat;
549 	u32 *buf = _buf;
550 
551 	while (bytes > 3) {
552 		stat = mxcmci_poll_status(host,
553 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
554 		if (stat)
555 			return stat;
556 		*buf++ = cpu_to_le32(mxcmci_readl(host, MMC_REG_BUFFER_ACCESS));
557 		bytes -= 4;
558 	}
559 
560 	if (bytes) {
561 		u8 *b = (u8 *)buf;
562 		u32 tmp;
563 
564 		stat = mxcmci_poll_status(host,
565 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
566 		if (stat)
567 			return stat;
568 		tmp = cpu_to_le32(mxcmci_readl(host, MMC_REG_BUFFER_ACCESS));
569 		memcpy(b, &tmp, bytes);
570 	}
571 
572 	return 0;
573 }
574 
575 static int mxcmci_push(struct mxcmci_host *host, void *_buf, int bytes)
576 {
577 	unsigned int stat;
578 	u32 *buf = _buf;
579 
580 	while (bytes > 3) {
581 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
582 		if (stat)
583 			return stat;
584 		mxcmci_writel(host, cpu_to_le32(*buf++), MMC_REG_BUFFER_ACCESS);
585 		bytes -= 4;
586 	}
587 
588 	if (bytes) {
589 		u8 *b = (u8 *)buf;
590 		u32 tmp;
591 
592 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
593 		if (stat)
594 			return stat;
595 
596 		memcpy(&tmp, b, bytes);
597 		mxcmci_writel(host, cpu_to_le32(tmp), MMC_REG_BUFFER_ACCESS);
598 	}
599 
600 	return mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
601 }
602 
603 static int mxcmci_transfer_data(struct mxcmci_host *host)
604 {
605 	struct mmc_data *data = host->req->data;
606 	struct scatterlist *sg;
607 	int stat, i;
608 
609 	host->data = data;
610 	host->datasize = 0;
611 
612 	if (data->flags & MMC_DATA_READ) {
613 		for_each_sg(data->sg, sg, data->sg_len, i) {
614 			stat = mxcmci_pull(host, sg_virt(sg), sg->length);
615 			if (stat)
616 				return stat;
617 			host->datasize += sg->length;
618 		}
619 	} else {
620 		for_each_sg(data->sg, sg, data->sg_len, i) {
621 			stat = mxcmci_push(host, sg_virt(sg), sg->length);
622 			if (stat)
623 				return stat;
624 			host->datasize += sg->length;
625 		}
626 		stat = mxcmci_poll_status(host, STATUS_WRITE_OP_DONE);
627 		if (stat)
628 			return stat;
629 	}
630 	return 0;
631 }
632 
633 static void mxcmci_datawork(struct work_struct *work)
634 {
635 	struct mxcmci_host *host = container_of(work, struct mxcmci_host,
636 						  datawork);
637 	int datastat = mxcmci_transfer_data(host);
638 
639 	mxcmci_writel(host, STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE,
640 		MMC_REG_STATUS);
641 	mxcmci_finish_data(host, datastat);
642 
643 	if (host->req->stop) {
644 		if (mxcmci_start_cmd(host, host->req->stop, 0)) {
645 			mxcmci_finish_request(host, host->req);
646 			return;
647 		}
648 	} else {
649 		mxcmci_finish_request(host, host->req);
650 	}
651 }
652 
653 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat)
654 {
655 	struct mmc_request *req;
656 	int data_error;
657 	unsigned long flags;
658 
659 	spin_lock_irqsave(&host->lock, flags);
660 
661 	if (!host->data) {
662 		spin_unlock_irqrestore(&host->lock, flags);
663 		return;
664 	}
665 
666 	if (!host->req) {
667 		spin_unlock_irqrestore(&host->lock, flags);
668 		return;
669 	}
670 
671 	req = host->req;
672 	if (!req->stop)
673 		host->req = NULL; /* we will handle finish req below */
674 
675 	data_error = mxcmci_finish_data(host, stat);
676 
677 	spin_unlock_irqrestore(&host->lock, flags);
678 
679 	if (data_error)
680 		return;
681 
682 	mxcmci_read_response(host, stat);
683 	host->cmd = NULL;
684 
685 	if (req->stop) {
686 		if (mxcmci_start_cmd(host, req->stop, 0)) {
687 			mxcmci_finish_request(host, req);
688 			return;
689 		}
690 	} else {
691 		mxcmci_finish_request(host, req);
692 	}
693 }
694 
695 static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat)
696 {
697 	mxcmci_read_response(host, stat);
698 	host->cmd = NULL;
699 
700 	if (!host->data && host->req) {
701 		mxcmci_finish_request(host, host->req);
702 		return;
703 	}
704 
705 	/* For the DMA case the DMA engine handles the data transfer
706 	 * automatically. For non DMA we have to do it ourselves.
707 	 * Don't do it in interrupt context though.
708 	 */
709 	if (!mxcmci_use_dma(host) && host->data)
710 		schedule_work(&host->datawork);
711 
712 }
713 
714 static irqreturn_t mxcmci_irq(int irq, void *devid)
715 {
716 	struct mxcmci_host *host = devid;
717 	bool sdio_irq;
718 	u32 stat;
719 
720 	stat = mxcmci_readl(host, MMC_REG_STATUS);
721 	mxcmci_writel(host,
722 		stat & ~(STATUS_SDIO_INT_ACTIVE | STATUS_DATA_TRANS_DONE |
723 			 STATUS_WRITE_OP_DONE),
724 		MMC_REG_STATUS);
725 
726 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
727 
728 	spin_lock(&host->lock);
729 	sdio_irq = (stat & STATUS_SDIO_INT_ACTIVE) && host->use_sdio;
730 	spin_unlock(&host->lock);
731 
732 	if (mxcmci_use_dma(host) && (stat & (STATUS_WRITE_OP_DONE)))
733 		mxcmci_writel(host, STATUS_WRITE_OP_DONE, MMC_REG_STATUS);
734 
735 	if (sdio_irq) {
736 		mxcmci_writel(host, STATUS_SDIO_INT_ACTIVE, MMC_REG_STATUS);
737 		mmc_signal_sdio_irq(host->mmc);
738 	}
739 
740 	if (stat & STATUS_END_CMD_RESP)
741 		mxcmci_cmd_done(host, stat);
742 
743 	if (mxcmci_use_dma(host) && (stat & STATUS_WRITE_OP_DONE)) {
744 		del_timer(&host->watchdog);
745 		mxcmci_data_done(host, stat);
746 	}
747 
748 	if (host->default_irq_mask &&
749 		  (stat & (STATUS_CARD_INSERTION | STATUS_CARD_REMOVAL)))
750 		mmc_detect_change(host->mmc, msecs_to_jiffies(200));
751 
752 	return IRQ_HANDLED;
753 }
754 
755 static void mxcmci_request(struct mmc_host *mmc, struct mmc_request *req)
756 {
757 	struct mxcmci_host *host = mmc_priv(mmc);
758 	unsigned int cmdat = host->cmdat;
759 	int error;
760 
761 	WARN_ON(host->req != NULL);
762 
763 	host->req = req;
764 	host->cmdat &= ~CMD_DAT_CONT_INIT;
765 
766 	if (host->dma)
767 		host->do_dma = 1;
768 
769 	if (req->data) {
770 		error = mxcmci_setup_data(host, req->data);
771 		if (error) {
772 			req->cmd->error = error;
773 			goto out;
774 		}
775 
776 
777 		cmdat |= CMD_DAT_CONT_DATA_ENABLE;
778 
779 		if (req->data->flags & MMC_DATA_WRITE)
780 			cmdat |= CMD_DAT_CONT_WRITE;
781 	}
782 
783 	error = mxcmci_start_cmd(host, req->cmd, cmdat);
784 
785 out:
786 	if (error)
787 		mxcmci_finish_request(host, req);
788 }
789 
790 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios)
791 {
792 	unsigned int divider;
793 	int prescaler = 0;
794 	unsigned int clk_in = clk_get_rate(host->clk_per);
795 
796 	while (prescaler <= 0x800) {
797 		for (divider = 1; divider <= 0xF; divider++) {
798 			int x;
799 
800 			x = (clk_in / (divider + 1));
801 
802 			if (prescaler)
803 				x /= (prescaler * 2);
804 
805 			if (x <= clk_ios)
806 				break;
807 		}
808 		if (divider < 0x10)
809 			break;
810 
811 		if (prescaler == 0)
812 			prescaler = 1;
813 		else
814 			prescaler <<= 1;
815 	}
816 
817 	mxcmci_writew(host, (prescaler << 4) | divider, MMC_REG_CLK_RATE);
818 
819 	dev_dbg(mmc_dev(host->mmc), "scaler: %d divider: %d in: %d out: %d\n",
820 			prescaler, divider, clk_in, clk_ios);
821 }
822 
823 static int mxcmci_setup_dma(struct mmc_host *mmc)
824 {
825 	struct mxcmci_host *host = mmc_priv(mmc);
826 	struct dma_slave_config *config = &host->dma_slave_config;
827 
828 	config->dst_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
829 	config->src_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
830 	config->dst_addr_width = 4;
831 	config->src_addr_width = 4;
832 	config->dst_maxburst = host->burstlen;
833 	config->src_maxburst = host->burstlen;
834 	config->device_fc = false;
835 
836 	return dmaengine_slave_config(host->dma, config);
837 }
838 
839 static void mxcmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
840 {
841 	struct mxcmci_host *host = mmc_priv(mmc);
842 	int burstlen, ret;
843 
844 	/*
845 	 * use burstlen of 64 (16 words) in 4 bit mode (--> reg value  0)
846 	 * use burstlen of 16 (4 words) in 1 bit mode (--> reg value 16)
847 	 */
848 	if (ios->bus_width == MMC_BUS_WIDTH_4)
849 		burstlen = 16;
850 	else
851 		burstlen = 4;
852 
853 	if (mxcmci_use_dma(host) && burstlen != host->burstlen) {
854 		host->burstlen = burstlen;
855 		ret = mxcmci_setup_dma(mmc);
856 		if (ret) {
857 			dev_err(mmc_dev(host->mmc),
858 				"failed to config DMA channel. Falling back to PIO\n");
859 			dma_release_channel(host->dma);
860 			host->do_dma = 0;
861 			host->dma = NULL;
862 		}
863 	}
864 
865 	if (ios->bus_width == MMC_BUS_WIDTH_4)
866 		host->cmdat |= CMD_DAT_CONT_BUS_WIDTH_4;
867 	else
868 		host->cmdat &= ~CMD_DAT_CONT_BUS_WIDTH_4;
869 
870 	if (host->power_mode != ios->power_mode) {
871 		host->power_mode = ios->power_mode;
872 		mxcmci_set_power(host, ios->vdd);
873 
874 		if (ios->power_mode == MMC_POWER_ON)
875 			host->cmdat |= CMD_DAT_CONT_INIT;
876 	}
877 
878 	if (ios->clock) {
879 		mxcmci_set_clk_rate(host, ios->clock);
880 		mxcmci_writew(host, STR_STP_CLK_START_CLK, MMC_REG_STR_STP_CLK);
881 	} else {
882 		mxcmci_writew(host, STR_STP_CLK_STOP_CLK, MMC_REG_STR_STP_CLK);
883 	}
884 
885 	host->clock = ios->clock;
886 }
887 
888 static irqreturn_t mxcmci_detect_irq(int irq, void *data)
889 {
890 	struct mmc_host *mmc = data;
891 
892 	dev_dbg(mmc_dev(mmc), "%s\n", __func__);
893 
894 	mmc_detect_change(mmc, msecs_to_jiffies(250));
895 	return IRQ_HANDLED;
896 }
897 
898 static int mxcmci_get_ro(struct mmc_host *mmc)
899 {
900 	struct mxcmci_host *host = mmc_priv(mmc);
901 
902 	if (host->pdata && host->pdata->get_ro)
903 		return !!host->pdata->get_ro(mmc_dev(mmc));
904 	/*
905 	 * If board doesn't support read only detection (no mmc_gpio
906 	 * context or gpio is invalid), then let the mmc core decide
907 	 * what to do.
908 	 */
909 	return mmc_gpio_get_ro(mmc);
910 }
911 
912 static void mxcmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
913 {
914 	struct mxcmci_host *host = mmc_priv(mmc);
915 	unsigned long flags;
916 	u32 int_cntr;
917 
918 	spin_lock_irqsave(&host->lock, flags);
919 	host->use_sdio = enable;
920 	int_cntr = mxcmci_readl(host, MMC_REG_INT_CNTR);
921 
922 	if (enable)
923 		int_cntr |= INT_SDIO_IRQ_EN;
924 	else
925 		int_cntr &= ~INT_SDIO_IRQ_EN;
926 
927 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
928 	spin_unlock_irqrestore(&host->lock, flags);
929 }
930 
931 static void mxcmci_init_card(struct mmc_host *host, struct mmc_card *card)
932 {
933 	struct mxcmci_host *mxcmci = mmc_priv(host);
934 
935 	/*
936 	 * MX3 SoCs have a silicon bug which corrupts CRC calculation of
937 	 * multi-block transfers when connected SDIO peripheral doesn't
938 	 * drive the BUSY line as required by the specs.
939 	 * One way to prevent this is to only allow 1-bit transfers.
940 	 */
941 
942 	if (is_imx31_mmc(mxcmci) && card->type == MMC_TYPE_SDIO)
943 		host->caps &= ~MMC_CAP_4_BIT_DATA;
944 	else
945 		host->caps |= MMC_CAP_4_BIT_DATA;
946 }
947 
948 static bool filter(struct dma_chan *chan, void *param)
949 {
950 	struct mxcmci_host *host = param;
951 
952 	if (!imx_dma_is_general_purpose(chan))
953 		return false;
954 
955 	chan->private = &host->dma_data;
956 
957 	return true;
958 }
959 
960 static void mxcmci_watchdog(struct timer_list *t)
961 {
962 	struct mxcmci_host *host = from_timer(host, t, watchdog);
963 	struct mmc_request *req = host->req;
964 	unsigned int stat = mxcmci_readl(host, MMC_REG_STATUS);
965 
966 	if (host->dma_dir == DMA_FROM_DEVICE) {
967 		dmaengine_terminate_all(host->dma);
968 		dev_err(mmc_dev(host->mmc),
969 			"%s: read time out (status = 0x%08x)\n",
970 			__func__, stat);
971 	} else {
972 		dev_err(mmc_dev(host->mmc),
973 			"%s: write time out (status = 0x%08x)\n",
974 			__func__, stat);
975 		mxcmci_softreset(host);
976 	}
977 
978 	/* Mark transfer as erroneus and inform the upper layers */
979 
980 	if (host->data)
981 		host->data->error = -ETIMEDOUT;
982 	host->req = NULL;
983 	host->cmd = NULL;
984 	host->data = NULL;
985 	mmc_request_done(host->mmc, req);
986 }
987 
988 static const struct mmc_host_ops mxcmci_ops = {
989 	.request		= mxcmci_request,
990 	.set_ios		= mxcmci_set_ios,
991 	.get_ro			= mxcmci_get_ro,
992 	.enable_sdio_irq	= mxcmci_enable_sdio_irq,
993 	.init_card		= mxcmci_init_card,
994 };
995 
996 static int mxcmci_probe(struct platform_device *pdev)
997 {
998 	struct mmc_host *mmc;
999 	struct mxcmci_host *host;
1000 	struct resource *res;
1001 	int ret = 0, irq;
1002 	bool dat3_card_detect = false;
1003 	dma_cap_mask_t mask;
1004 	const struct of_device_id *of_id;
1005 	struct imxmmc_platform_data *pdata = pdev->dev.platform_data;
1006 
1007 	pr_info("i.MX/MPC512x SDHC driver\n");
1008 
1009 	of_id = of_match_device(mxcmci_of_match, &pdev->dev);
1010 
1011 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1012 	irq = platform_get_irq(pdev, 0);
1013 	if (irq < 0) {
1014 		dev_err(&pdev->dev, "failed to get IRQ: %d\n", irq);
1015 		return irq;
1016 	}
1017 
1018 	mmc = mmc_alloc_host(sizeof(*host), &pdev->dev);
1019 	if (!mmc)
1020 		return -ENOMEM;
1021 
1022 	host = mmc_priv(mmc);
1023 
1024 	host->base = devm_ioremap_resource(&pdev->dev, res);
1025 	if (IS_ERR(host->base)) {
1026 		ret = PTR_ERR(host->base);
1027 		goto out_free;
1028 	}
1029 
1030 	host->phys_base = res->start;
1031 
1032 	ret = mmc_of_parse(mmc);
1033 	if (ret)
1034 		goto out_free;
1035 	mmc->ops = &mxcmci_ops;
1036 
1037 	/* For devicetree parsing, the bus width is read from devicetree */
1038 	if (pdata)
1039 		mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
1040 	else
1041 		mmc->caps |= MMC_CAP_SDIO_IRQ;
1042 
1043 	/* MMC core transfer sizes tunable parameters */
1044 	mmc->max_blk_size = 2048;
1045 	mmc->max_blk_count = 65535;
1046 	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
1047 	mmc->max_seg_size = mmc->max_req_size;
1048 
1049 	if (of_id) {
1050 		const struct platform_device_id *id_entry = of_id->data;
1051 		host->devtype = id_entry->driver_data;
1052 	} else {
1053 		host->devtype = pdev->id_entry->driver_data;
1054 	}
1055 
1056 	/* adjust max_segs after devtype detection */
1057 	if (!is_mpc512x_mmc(host))
1058 		mmc->max_segs = 64;
1059 
1060 	host->mmc = mmc;
1061 	host->pdata = pdata;
1062 	spin_lock_init(&host->lock);
1063 
1064 	if (pdata)
1065 		dat3_card_detect = pdata->dat3_card_detect;
1066 	else if (mmc_card_is_removable(mmc)
1067 			&& !of_property_read_bool(pdev->dev.of_node, "cd-gpios"))
1068 		dat3_card_detect = true;
1069 
1070 	ret = mmc_regulator_get_supply(mmc);
1071 	if (ret)
1072 		goto out_free;
1073 
1074 	if (!mmc->ocr_avail) {
1075 		if (pdata && pdata->ocr_avail)
1076 			mmc->ocr_avail = pdata->ocr_avail;
1077 		else
1078 			mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
1079 	}
1080 
1081 	if (dat3_card_detect)
1082 		host->default_irq_mask =
1083 			INT_CARD_INSERTION_EN | INT_CARD_REMOVAL_EN;
1084 	else
1085 		host->default_irq_mask = 0;
1086 
1087 	host->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1088 	if (IS_ERR(host->clk_ipg)) {
1089 		ret = PTR_ERR(host->clk_ipg);
1090 		goto out_free;
1091 	}
1092 
1093 	host->clk_per = devm_clk_get(&pdev->dev, "per");
1094 	if (IS_ERR(host->clk_per)) {
1095 		ret = PTR_ERR(host->clk_per);
1096 		goto out_free;
1097 	}
1098 
1099 	ret = clk_prepare_enable(host->clk_per);
1100 	if (ret)
1101 		goto out_free;
1102 
1103 	ret = clk_prepare_enable(host->clk_ipg);
1104 	if (ret)
1105 		goto out_clk_per_put;
1106 
1107 	mxcmci_softreset(host);
1108 
1109 	host->rev_no = mxcmci_readw(host, MMC_REG_REV_NO);
1110 	if (host->rev_no != 0x400) {
1111 		ret = -ENODEV;
1112 		dev_err(mmc_dev(host->mmc), "wrong rev.no. 0x%08x. aborting.\n",
1113 			host->rev_no);
1114 		goto out_clk_put;
1115 	}
1116 
1117 	mmc->f_min = clk_get_rate(host->clk_per) >> 16;
1118 	mmc->f_max = clk_get_rate(host->clk_per) >> 1;
1119 
1120 	/* recommended in data sheet */
1121 	mxcmci_writew(host, 0x2db4, MMC_REG_READ_TO);
1122 
1123 	mxcmci_writel(host, host->default_irq_mask, MMC_REG_INT_CNTR);
1124 
1125 	if (!host->pdata) {
1126 		host->dma = dma_request_slave_channel(&pdev->dev, "rx-tx");
1127 	} else {
1128 		res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1129 		if (res) {
1130 			host->dmareq = res->start;
1131 			host->dma_data.peripheral_type = IMX_DMATYPE_SDHC;
1132 			host->dma_data.priority = DMA_PRIO_LOW;
1133 			host->dma_data.dma_request = host->dmareq;
1134 			dma_cap_zero(mask);
1135 			dma_cap_set(DMA_SLAVE, mask);
1136 			host->dma = dma_request_channel(mask, filter, host);
1137 		}
1138 	}
1139 	if (host->dma)
1140 		mmc->max_seg_size = dma_get_max_seg_size(
1141 				host->dma->device->dev);
1142 	else
1143 		dev_info(mmc_dev(host->mmc), "dma not available. Using PIO\n");
1144 
1145 	INIT_WORK(&host->datawork, mxcmci_datawork);
1146 
1147 	ret = devm_request_irq(&pdev->dev, irq, mxcmci_irq, 0,
1148 			       dev_name(&pdev->dev), host);
1149 	if (ret)
1150 		goto out_free_dma;
1151 
1152 	platform_set_drvdata(pdev, mmc);
1153 
1154 	if (host->pdata && host->pdata->init) {
1155 		ret = host->pdata->init(&pdev->dev, mxcmci_detect_irq,
1156 				host->mmc);
1157 		if (ret)
1158 			goto out_free_dma;
1159 	}
1160 
1161 	timer_setup(&host->watchdog, mxcmci_watchdog, 0);
1162 
1163 	mmc_add_host(mmc);
1164 
1165 	return 0;
1166 
1167 out_free_dma:
1168 	if (host->dma)
1169 		dma_release_channel(host->dma);
1170 
1171 out_clk_put:
1172 	clk_disable_unprepare(host->clk_ipg);
1173 out_clk_per_put:
1174 	clk_disable_unprepare(host->clk_per);
1175 
1176 out_free:
1177 	mmc_free_host(mmc);
1178 
1179 	return ret;
1180 }
1181 
1182 static int mxcmci_remove(struct platform_device *pdev)
1183 {
1184 	struct mmc_host *mmc = platform_get_drvdata(pdev);
1185 	struct mxcmci_host *host = mmc_priv(mmc);
1186 
1187 	mmc_remove_host(mmc);
1188 
1189 	if (host->pdata && host->pdata->exit)
1190 		host->pdata->exit(&pdev->dev, mmc);
1191 
1192 	if (host->dma)
1193 		dma_release_channel(host->dma);
1194 
1195 	clk_disable_unprepare(host->clk_per);
1196 	clk_disable_unprepare(host->clk_ipg);
1197 
1198 	mmc_free_host(mmc);
1199 
1200 	return 0;
1201 }
1202 
1203 #ifdef CONFIG_PM_SLEEP
1204 static int mxcmci_suspend(struct device *dev)
1205 {
1206 	struct mmc_host *mmc = dev_get_drvdata(dev);
1207 	struct mxcmci_host *host = mmc_priv(mmc);
1208 
1209 	clk_disable_unprepare(host->clk_per);
1210 	clk_disable_unprepare(host->clk_ipg);
1211 	return 0;
1212 }
1213 
1214 static int mxcmci_resume(struct device *dev)
1215 {
1216 	struct mmc_host *mmc = dev_get_drvdata(dev);
1217 	struct mxcmci_host *host = mmc_priv(mmc);
1218 	int ret;
1219 
1220 	ret = clk_prepare_enable(host->clk_per);
1221 	if (ret)
1222 		return ret;
1223 
1224 	ret = clk_prepare_enable(host->clk_ipg);
1225 	if (ret)
1226 		clk_disable_unprepare(host->clk_per);
1227 
1228 	return ret;
1229 }
1230 #endif
1231 
1232 static SIMPLE_DEV_PM_OPS(mxcmci_pm_ops, mxcmci_suspend, mxcmci_resume);
1233 
1234 static struct platform_driver mxcmci_driver = {
1235 	.probe		= mxcmci_probe,
1236 	.remove		= mxcmci_remove,
1237 	.id_table	= mxcmci_devtype,
1238 	.driver		= {
1239 		.name		= DRIVER_NAME,
1240 		.pm	= &mxcmci_pm_ops,
1241 		.of_match_table	= mxcmci_of_match,
1242 	}
1243 };
1244 
1245 module_platform_driver(mxcmci_driver);
1246 
1247 MODULE_DESCRIPTION("i.MX Multimedia Card Interface Driver");
1248 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1249 MODULE_LICENSE("GPL");
1250 MODULE_ALIAS("platform:mxc-mmc");
1251