xref: /openbmc/linux/drivers/mmc/host/mxcmmc.c (revision 275876e2)
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 #include <linux/of.h>
38 #include <linux/of_device.h>
39 #include <linux/of_dma.h>
40 #include <linux/of_gpio.h>
41 #include <linux/mmc/slot-gpio.h>
42 
43 #include <asm/dma.h>
44 #include <asm/irq.h>
45 #include <linux/platform_data/mmc-mxcmmc.h>
46 
47 #include <linux/platform_data/dma-imx.h>
48 
49 #define DRIVER_NAME "mxc-mmc"
50 #define MXCMCI_TIMEOUT_MS 10000
51 
52 #define MMC_REG_STR_STP_CLK		0x00
53 #define MMC_REG_STATUS			0x04
54 #define MMC_REG_CLK_RATE		0x08
55 #define MMC_REG_CMD_DAT_CONT		0x0C
56 #define MMC_REG_RES_TO			0x10
57 #define MMC_REG_READ_TO			0x14
58 #define MMC_REG_BLK_LEN			0x18
59 #define MMC_REG_NOB			0x1C
60 #define MMC_REG_REV_NO			0x20
61 #define MMC_REG_INT_CNTR		0x24
62 #define MMC_REG_CMD			0x28
63 #define MMC_REG_ARG			0x2C
64 #define MMC_REG_RES_FIFO		0x34
65 #define MMC_REG_BUFFER_ACCESS		0x38
66 
67 #define STR_STP_CLK_RESET               (1 << 3)
68 #define STR_STP_CLK_START_CLK           (1 << 1)
69 #define STR_STP_CLK_STOP_CLK            (1 << 0)
70 
71 #define STATUS_CARD_INSERTION		(1 << 31)
72 #define STATUS_CARD_REMOVAL		(1 << 30)
73 #define STATUS_YBUF_EMPTY		(1 << 29)
74 #define STATUS_XBUF_EMPTY		(1 << 28)
75 #define STATUS_YBUF_FULL		(1 << 27)
76 #define STATUS_XBUF_FULL		(1 << 26)
77 #define STATUS_BUF_UND_RUN		(1 << 25)
78 #define STATUS_BUF_OVFL			(1 << 24)
79 #define STATUS_SDIO_INT_ACTIVE		(1 << 14)
80 #define STATUS_END_CMD_RESP		(1 << 13)
81 #define STATUS_WRITE_OP_DONE		(1 << 12)
82 #define STATUS_DATA_TRANS_DONE		(1 << 11)
83 #define STATUS_READ_OP_DONE		(1 << 11)
84 #define STATUS_WR_CRC_ERROR_CODE_MASK	(3 << 10)
85 #define STATUS_CARD_BUS_CLK_RUN		(1 << 8)
86 #define STATUS_BUF_READ_RDY		(1 << 7)
87 #define STATUS_BUF_WRITE_RDY		(1 << 6)
88 #define STATUS_RESP_CRC_ERR		(1 << 5)
89 #define STATUS_CRC_READ_ERR		(1 << 3)
90 #define STATUS_CRC_WRITE_ERR		(1 << 2)
91 #define STATUS_TIME_OUT_RESP		(1 << 1)
92 #define STATUS_TIME_OUT_READ		(1 << 0)
93 #define STATUS_ERR_MASK			0x2f
94 
95 #define CMD_DAT_CONT_CMD_RESP_LONG_OFF	(1 << 12)
96 #define CMD_DAT_CONT_STOP_READWAIT	(1 << 11)
97 #define CMD_DAT_CONT_START_READWAIT	(1 << 10)
98 #define CMD_DAT_CONT_BUS_WIDTH_4	(2 << 8)
99 #define CMD_DAT_CONT_INIT		(1 << 7)
100 #define CMD_DAT_CONT_WRITE		(1 << 4)
101 #define CMD_DAT_CONT_DATA_ENABLE	(1 << 3)
102 #define CMD_DAT_CONT_RESPONSE_48BIT_CRC	(1 << 0)
103 #define CMD_DAT_CONT_RESPONSE_136BIT	(2 << 0)
104 #define CMD_DAT_CONT_RESPONSE_48BIT	(3 << 0)
105 
106 #define INT_SDIO_INT_WKP_EN		(1 << 18)
107 #define INT_CARD_INSERTION_WKP_EN	(1 << 17)
108 #define INT_CARD_REMOVAL_WKP_EN		(1 << 16)
109 #define INT_CARD_INSERTION_EN		(1 << 15)
110 #define INT_CARD_REMOVAL_EN		(1 << 14)
111 #define INT_SDIO_IRQ_EN			(1 << 13)
112 #define INT_DAT0_EN			(1 << 12)
113 #define INT_BUF_READ_EN			(1 << 4)
114 #define INT_BUF_WRITE_EN		(1 << 3)
115 #define INT_END_CMD_RES_EN		(1 << 2)
116 #define INT_WRITE_OP_DONE_EN		(1 << 1)
117 #define INT_READ_OP_EN			(1 << 0)
118 
119 enum mxcmci_type {
120 	IMX21_MMC,
121 	IMX31_MMC,
122 	MPC512X_MMC,
123 };
124 
125 struct mxcmci_host {
126 	struct mmc_host		*mmc;
127 	void __iomem		*base;
128 	dma_addr_t		phys_base;
129 	int			detect_irq;
130 	struct dma_chan		*dma;
131 	struct dma_async_tx_descriptor *desc;
132 	int			do_dma;
133 	int			default_irq_mask;
134 	int			use_sdio;
135 	unsigned int		power_mode;
136 	struct imxmmc_platform_data *pdata;
137 
138 	struct mmc_request	*req;
139 	struct mmc_command	*cmd;
140 	struct mmc_data		*data;
141 
142 	unsigned int		datasize;
143 	unsigned int		dma_dir;
144 
145 	u16			rev_no;
146 	unsigned int		cmdat;
147 
148 	struct clk		*clk_ipg;
149 	struct clk		*clk_per;
150 
151 	int			clock;
152 
153 	struct work_struct	datawork;
154 	spinlock_t		lock;
155 
156 	int			burstlen;
157 	int			dmareq;
158 	struct dma_slave_config dma_slave_config;
159 	struct imx_dma_data	dma_data;
160 
161 	struct timer_list	watchdog;
162 	enum mxcmci_type	devtype;
163 };
164 
165 static const struct platform_device_id mxcmci_devtype[] = {
166 	{
167 		.name = "imx21-mmc",
168 		.driver_data = IMX21_MMC,
169 	}, {
170 		.name = "imx31-mmc",
171 		.driver_data = IMX31_MMC,
172 	}, {
173 		.name = "mpc512x-sdhc",
174 		.driver_data = MPC512X_MMC,
175 	}, {
176 		/* sentinel */
177 	}
178 };
179 MODULE_DEVICE_TABLE(platform, mxcmci_devtype);
180 
181 static const struct of_device_id mxcmci_of_match[] = {
182 	{
183 		.compatible = "fsl,imx21-mmc",
184 		.data = &mxcmci_devtype[IMX21_MMC],
185 	}, {
186 		.compatible = "fsl,imx31-mmc",
187 		.data = &mxcmci_devtype[IMX31_MMC],
188 	}, {
189 		.compatible = "fsl,mpc5121-sdhc",
190 		.data = &mxcmci_devtype[MPC512X_MMC],
191 	}, {
192 		/* sentinel */
193 	}
194 };
195 MODULE_DEVICE_TABLE(of, mxcmci_of_match);
196 
197 static inline int is_imx31_mmc(struct mxcmci_host *host)
198 {
199 	return host->devtype == IMX31_MMC;
200 }
201 
202 static inline int is_mpc512x_mmc(struct mxcmci_host *host)
203 {
204 	return host->devtype == MPC512X_MMC;
205 }
206 
207 static inline u32 mxcmci_readl(struct mxcmci_host *host, int reg)
208 {
209 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
210 		return ioread32be(host->base + reg);
211 	else
212 		return readl(host->base + reg);
213 }
214 
215 static inline void mxcmci_writel(struct mxcmci_host *host, u32 val, int reg)
216 {
217 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
218 		iowrite32be(val, host->base + reg);
219 	else
220 		writel(val, host->base + reg);
221 }
222 
223 static inline u16 mxcmci_readw(struct mxcmci_host *host, int reg)
224 {
225 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
226 		return ioread32be(host->base + reg);
227 	else
228 		return readw(host->base + reg);
229 }
230 
231 static inline void mxcmci_writew(struct mxcmci_host *host, u16 val, int reg)
232 {
233 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
234 		iowrite32be(val, host->base + reg);
235 	else
236 		writew(val, host->base + reg);
237 }
238 
239 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios);
240 
241 static void mxcmci_set_power(struct mxcmci_host *host, unsigned int vdd)
242 {
243 	if (!IS_ERR(host->mmc->supply.vmmc)) {
244 		if (host->power_mode == MMC_POWER_UP)
245 			mmc_regulator_set_ocr(host->mmc,
246 					      host->mmc->supply.vmmc, vdd);
247 		else if (host->power_mode == MMC_POWER_OFF)
248 			mmc_regulator_set_ocr(host->mmc,
249 					      host->mmc->supply.vmmc, 0);
250 	}
251 
252 	if (host->pdata && host->pdata->setpower)
253 		host->pdata->setpower(mmc_dev(host->mmc), vdd);
254 }
255 
256 static inline int mxcmci_use_dma(struct mxcmci_host *host)
257 {
258 	return host->do_dma;
259 }
260 
261 static void mxcmci_softreset(struct mxcmci_host *host)
262 {
263 	int i;
264 
265 	dev_dbg(mmc_dev(host->mmc), "mxcmci_softreset\n");
266 
267 	/* reset sequence */
268 	mxcmci_writew(host, STR_STP_CLK_RESET, MMC_REG_STR_STP_CLK);
269 	mxcmci_writew(host, STR_STP_CLK_RESET | STR_STP_CLK_START_CLK,
270 			MMC_REG_STR_STP_CLK);
271 
272 	for (i = 0; i < 8; i++)
273 		mxcmci_writew(host, STR_STP_CLK_START_CLK, MMC_REG_STR_STP_CLK);
274 
275 	mxcmci_writew(host, 0xff, MMC_REG_RES_TO);
276 }
277 
278 #if IS_ENABLED(CONFIG_PPC_MPC512x)
279 static inline void buffer_swap32(u32 *buf, int len)
280 {
281 	int i;
282 
283 	for (i = 0; i < ((len + 3) / 4); i++) {
284 		st_le32(buf, *buf);
285 		buf++;
286 	}
287 }
288 
289 static void mxcmci_swap_buffers(struct mmc_data *data)
290 {
291 	struct scatterlist *sg;
292 	int i;
293 
294 	for_each_sg(data->sg, sg, data->sg_len, i)
295 		buffer_swap32(sg_virt(sg), sg->length);
296 }
297 #else
298 static inline void mxcmci_swap_buffers(struct mmc_data *data) {}
299 #endif
300 
301 static int mxcmci_setup_data(struct mxcmci_host *host, struct mmc_data *data)
302 {
303 	unsigned int nob = data->blocks;
304 	unsigned int blksz = data->blksz;
305 	unsigned int datasize = nob * blksz;
306 	struct scatterlist *sg;
307 	enum dma_transfer_direction slave_dirn;
308 	int i, nents;
309 
310 	if (data->flags & MMC_DATA_STREAM)
311 		nob = 0xffff;
312 
313 	host->data = data;
314 	data->bytes_xfered = 0;
315 
316 	mxcmci_writew(host, nob, MMC_REG_NOB);
317 	mxcmci_writew(host, blksz, MMC_REG_BLK_LEN);
318 	host->datasize = datasize;
319 
320 	if (!mxcmci_use_dma(host))
321 		return 0;
322 
323 	for_each_sg(data->sg, sg, data->sg_len, i) {
324 		if (sg->offset & 3 || sg->length & 3 || sg->length < 512) {
325 			host->do_dma = 0;
326 			return 0;
327 		}
328 	}
329 
330 	if (data->flags & MMC_DATA_READ) {
331 		host->dma_dir = DMA_FROM_DEVICE;
332 		slave_dirn = DMA_DEV_TO_MEM;
333 	} else {
334 		host->dma_dir = DMA_TO_DEVICE;
335 		slave_dirn = DMA_MEM_TO_DEV;
336 
337 		mxcmci_swap_buffers(data);
338 	}
339 
340 	nents = dma_map_sg(host->dma->device->dev, data->sg,
341 				     data->sg_len,  host->dma_dir);
342 	if (nents != data->sg_len)
343 		return -EINVAL;
344 
345 	host->desc = dmaengine_prep_slave_sg(host->dma,
346 		data->sg, data->sg_len, slave_dirn,
347 		DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
348 
349 	if (!host->desc) {
350 		dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
351 				host->dma_dir);
352 		host->do_dma = 0;
353 		return 0; /* Fall back to PIO */
354 	}
355 	wmb();
356 
357 	dmaengine_submit(host->desc);
358 	dma_async_issue_pending(host->dma);
359 
360 	mod_timer(&host->watchdog, jiffies + msecs_to_jiffies(MXCMCI_TIMEOUT_MS));
361 
362 	return 0;
363 }
364 
365 static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat);
366 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat);
367 
368 static void mxcmci_dma_callback(void *data)
369 {
370 	struct mxcmci_host *host = data;
371 	u32 stat;
372 
373 	del_timer(&host->watchdog);
374 
375 	stat = mxcmci_readl(host, MMC_REG_STATUS);
376 	mxcmci_writel(host, stat & ~STATUS_DATA_TRANS_DONE, MMC_REG_STATUS);
377 
378 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
379 
380 	if (stat & STATUS_READ_OP_DONE)
381 		mxcmci_writel(host, STATUS_READ_OP_DONE, MMC_REG_STATUS);
382 
383 	mxcmci_data_done(host, stat);
384 }
385 
386 static int mxcmci_start_cmd(struct mxcmci_host *host, struct mmc_command *cmd,
387 		unsigned int cmdat)
388 {
389 	u32 int_cntr = host->default_irq_mask;
390 	unsigned long flags;
391 
392 	WARN_ON(host->cmd != NULL);
393 	host->cmd = cmd;
394 
395 	switch (mmc_resp_type(cmd)) {
396 	case MMC_RSP_R1: /* short CRC, OPCODE */
397 	case MMC_RSP_R1B:/* short CRC, OPCODE, BUSY */
398 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT_CRC;
399 		break;
400 	case MMC_RSP_R2: /* long 136 bit + CRC */
401 		cmdat |= CMD_DAT_CONT_RESPONSE_136BIT;
402 		break;
403 	case MMC_RSP_R3: /* short */
404 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT;
405 		break;
406 	case MMC_RSP_NONE:
407 		break;
408 	default:
409 		dev_err(mmc_dev(host->mmc), "unhandled response type 0x%x\n",
410 				mmc_resp_type(cmd));
411 		cmd->error = -EINVAL;
412 		return -EINVAL;
413 	}
414 
415 	int_cntr = INT_END_CMD_RES_EN;
416 
417 	if (mxcmci_use_dma(host)) {
418 		if (host->dma_dir == DMA_FROM_DEVICE) {
419 			host->desc->callback = mxcmci_dma_callback;
420 			host->desc->callback_param = host;
421 		} else {
422 			int_cntr |= INT_WRITE_OP_DONE_EN;
423 		}
424 	}
425 
426 	spin_lock_irqsave(&host->lock, flags);
427 	if (host->use_sdio)
428 		int_cntr |= INT_SDIO_IRQ_EN;
429 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
430 	spin_unlock_irqrestore(&host->lock, flags);
431 
432 	mxcmci_writew(host, cmd->opcode, MMC_REG_CMD);
433 	mxcmci_writel(host, cmd->arg, MMC_REG_ARG);
434 	mxcmci_writew(host, cmdat, MMC_REG_CMD_DAT_CONT);
435 
436 	return 0;
437 }
438 
439 static void mxcmci_finish_request(struct mxcmci_host *host,
440 		struct mmc_request *req)
441 {
442 	u32 int_cntr = host->default_irq_mask;
443 	unsigned long flags;
444 
445 	spin_lock_irqsave(&host->lock, flags);
446 	if (host->use_sdio)
447 		int_cntr |= INT_SDIO_IRQ_EN;
448 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
449 	spin_unlock_irqrestore(&host->lock, flags);
450 
451 	host->req = NULL;
452 	host->cmd = NULL;
453 	host->data = NULL;
454 
455 	mmc_request_done(host->mmc, req);
456 }
457 
458 static int mxcmci_finish_data(struct mxcmci_host *host, unsigned int stat)
459 {
460 	struct mmc_data *data = host->data;
461 	int data_error;
462 
463 	if (mxcmci_use_dma(host)) {
464 		dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
465 				host->dma_dir);
466 		mxcmci_swap_buffers(data);
467 	}
468 
469 	if (stat & STATUS_ERR_MASK) {
470 		dev_dbg(mmc_dev(host->mmc), "request failed. status: 0x%08x\n",
471 				stat);
472 		if (stat & STATUS_CRC_READ_ERR) {
473 			dev_err(mmc_dev(host->mmc), "%s: -EILSEQ\n", __func__);
474 			data->error = -EILSEQ;
475 		} else if (stat & STATUS_CRC_WRITE_ERR) {
476 			u32 err_code = (stat >> 9) & 0x3;
477 			if (err_code == 2) { /* No CRC response */
478 				dev_err(mmc_dev(host->mmc),
479 					"%s: No CRC -ETIMEDOUT\n", __func__);
480 				data->error = -ETIMEDOUT;
481 			} else {
482 				dev_err(mmc_dev(host->mmc),
483 					"%s: -EILSEQ\n", __func__);
484 				data->error = -EILSEQ;
485 			}
486 		} else if (stat & STATUS_TIME_OUT_READ) {
487 			dev_err(mmc_dev(host->mmc),
488 				"%s: read -ETIMEDOUT\n", __func__);
489 			data->error = -ETIMEDOUT;
490 		} else {
491 			dev_err(mmc_dev(host->mmc), "%s: -EIO\n", __func__);
492 			data->error = -EIO;
493 		}
494 	} else {
495 		data->bytes_xfered = host->datasize;
496 	}
497 
498 	data_error = data->error;
499 
500 	host->data = NULL;
501 
502 	return data_error;
503 }
504 
505 static void mxcmci_read_response(struct mxcmci_host *host, unsigned int stat)
506 {
507 	struct mmc_command *cmd = host->cmd;
508 	int i;
509 	u32 a, b, c;
510 
511 	if (!cmd)
512 		return;
513 
514 	if (stat & STATUS_TIME_OUT_RESP) {
515 		dev_dbg(mmc_dev(host->mmc), "CMD TIMEOUT\n");
516 		cmd->error = -ETIMEDOUT;
517 	} else if (stat & STATUS_RESP_CRC_ERR && cmd->flags & MMC_RSP_CRC) {
518 		dev_dbg(mmc_dev(host->mmc), "cmd crc error\n");
519 		cmd->error = -EILSEQ;
520 	}
521 
522 	if (cmd->flags & MMC_RSP_PRESENT) {
523 		if (cmd->flags & MMC_RSP_136) {
524 			for (i = 0; i < 4; i++) {
525 				a = mxcmci_readw(host, MMC_REG_RES_FIFO);
526 				b = mxcmci_readw(host, MMC_REG_RES_FIFO);
527 				cmd->resp[i] = a << 16 | b;
528 			}
529 		} else {
530 			a = mxcmci_readw(host, MMC_REG_RES_FIFO);
531 			b = mxcmci_readw(host, MMC_REG_RES_FIFO);
532 			c = mxcmci_readw(host, MMC_REG_RES_FIFO);
533 			cmd->resp[0] = a << 24 | b << 8 | c >> 8;
534 		}
535 	}
536 }
537 
538 static int mxcmci_poll_status(struct mxcmci_host *host, u32 mask)
539 {
540 	u32 stat;
541 	unsigned long timeout = jiffies + HZ;
542 
543 	do {
544 		stat = mxcmci_readl(host, MMC_REG_STATUS);
545 		if (stat & STATUS_ERR_MASK)
546 			return stat;
547 		if (time_after(jiffies, timeout)) {
548 			mxcmci_softreset(host);
549 			mxcmci_set_clk_rate(host, host->clock);
550 			return STATUS_TIME_OUT_READ;
551 		}
552 		if (stat & mask)
553 			return 0;
554 		cpu_relax();
555 	} while (1);
556 }
557 
558 static int mxcmci_pull(struct mxcmci_host *host, void *_buf, int bytes)
559 {
560 	unsigned int stat;
561 	u32 *buf = _buf;
562 
563 	while (bytes > 3) {
564 		stat = mxcmci_poll_status(host,
565 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
566 		if (stat)
567 			return stat;
568 		*buf++ = cpu_to_le32(mxcmci_readl(host, MMC_REG_BUFFER_ACCESS));
569 		bytes -= 4;
570 	}
571 
572 	if (bytes) {
573 		u8 *b = (u8 *)buf;
574 		u32 tmp;
575 
576 		stat = mxcmci_poll_status(host,
577 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
578 		if (stat)
579 			return stat;
580 		tmp = cpu_to_le32(mxcmci_readl(host, MMC_REG_BUFFER_ACCESS));
581 		memcpy(b, &tmp, bytes);
582 	}
583 
584 	return 0;
585 }
586 
587 static int mxcmci_push(struct mxcmci_host *host, void *_buf, int bytes)
588 {
589 	unsigned int stat;
590 	u32 *buf = _buf;
591 
592 	while (bytes > 3) {
593 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
594 		if (stat)
595 			return stat;
596 		mxcmci_writel(host, cpu_to_le32(*buf++), MMC_REG_BUFFER_ACCESS);
597 		bytes -= 4;
598 	}
599 
600 	if (bytes) {
601 		u8 *b = (u8 *)buf;
602 		u32 tmp;
603 
604 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
605 		if (stat)
606 			return stat;
607 
608 		memcpy(&tmp, b, bytes);
609 		mxcmci_writel(host, cpu_to_le32(tmp), MMC_REG_BUFFER_ACCESS);
610 	}
611 
612 	stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
613 	if (stat)
614 		return stat;
615 
616 	return 0;
617 }
618 
619 static int mxcmci_transfer_data(struct mxcmci_host *host)
620 {
621 	struct mmc_data *data = host->req->data;
622 	struct scatterlist *sg;
623 	int stat, i;
624 
625 	host->data = data;
626 	host->datasize = 0;
627 
628 	if (data->flags & MMC_DATA_READ) {
629 		for_each_sg(data->sg, sg, data->sg_len, i) {
630 			stat = mxcmci_pull(host, sg_virt(sg), sg->length);
631 			if (stat)
632 				return stat;
633 			host->datasize += sg->length;
634 		}
635 	} else {
636 		for_each_sg(data->sg, sg, data->sg_len, i) {
637 			stat = mxcmci_push(host, sg_virt(sg), sg->length);
638 			if (stat)
639 				return stat;
640 			host->datasize += sg->length;
641 		}
642 		stat = mxcmci_poll_status(host, STATUS_WRITE_OP_DONE);
643 		if (stat)
644 			return stat;
645 	}
646 	return 0;
647 }
648 
649 static void mxcmci_datawork(struct work_struct *work)
650 {
651 	struct mxcmci_host *host = container_of(work, struct mxcmci_host,
652 						  datawork);
653 	int datastat = mxcmci_transfer_data(host);
654 
655 	mxcmci_writel(host, STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE,
656 		MMC_REG_STATUS);
657 	mxcmci_finish_data(host, datastat);
658 
659 	if (host->req->stop) {
660 		if (mxcmci_start_cmd(host, host->req->stop, 0)) {
661 			mxcmci_finish_request(host, host->req);
662 			return;
663 		}
664 	} else {
665 		mxcmci_finish_request(host, host->req);
666 	}
667 }
668 
669 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat)
670 {
671 	struct mmc_request *req;
672 	int data_error;
673 	unsigned long flags;
674 
675 	spin_lock_irqsave(&host->lock, flags);
676 
677 	if (!host->data) {
678 		spin_unlock_irqrestore(&host->lock, flags);
679 		return;
680 	}
681 
682 	if (!host->req) {
683 		spin_unlock_irqrestore(&host->lock, flags);
684 		return;
685 	}
686 
687 	req = host->req;
688 	if (!req->stop)
689 		host->req = NULL; /* we will handle finish req below */
690 
691 	data_error = mxcmci_finish_data(host, stat);
692 
693 	spin_unlock_irqrestore(&host->lock, flags);
694 
695 	mxcmci_read_response(host, stat);
696 	host->cmd = NULL;
697 
698 	if (req->stop) {
699 		if (mxcmci_start_cmd(host, req->stop, 0)) {
700 			mxcmci_finish_request(host, req);
701 			return;
702 		}
703 	} else {
704 		mxcmci_finish_request(host, req);
705 	}
706 }
707 
708 static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat)
709 {
710 	mxcmci_read_response(host, stat);
711 	host->cmd = NULL;
712 
713 	if (!host->data && host->req) {
714 		mxcmci_finish_request(host, host->req);
715 		return;
716 	}
717 
718 	/* For the DMA case the DMA engine handles the data transfer
719 	 * automatically. For non DMA we have to do it ourselves.
720 	 * Don't do it in interrupt context though.
721 	 */
722 	if (!mxcmci_use_dma(host) && host->data)
723 		schedule_work(&host->datawork);
724 
725 }
726 
727 static irqreturn_t mxcmci_irq(int irq, void *devid)
728 {
729 	struct mxcmci_host *host = devid;
730 	unsigned long flags;
731 	bool sdio_irq;
732 	u32 stat;
733 
734 	stat = mxcmci_readl(host, MMC_REG_STATUS);
735 	mxcmci_writel(host,
736 		stat & ~(STATUS_SDIO_INT_ACTIVE | STATUS_DATA_TRANS_DONE |
737 			 STATUS_WRITE_OP_DONE),
738 		MMC_REG_STATUS);
739 
740 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
741 
742 	spin_lock_irqsave(&host->lock, flags);
743 	sdio_irq = (stat & STATUS_SDIO_INT_ACTIVE) && host->use_sdio;
744 	spin_unlock_irqrestore(&host->lock, flags);
745 
746 	if (mxcmci_use_dma(host) &&
747 	    (stat & (STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE)))
748 		mxcmci_writel(host, STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE,
749 			MMC_REG_STATUS);
750 
751 	if (sdio_irq) {
752 		mxcmci_writel(host, STATUS_SDIO_INT_ACTIVE, MMC_REG_STATUS);
753 		mmc_signal_sdio_irq(host->mmc);
754 	}
755 
756 	if (stat & STATUS_END_CMD_RESP)
757 		mxcmci_cmd_done(host, stat);
758 
759 	if (mxcmci_use_dma(host) &&
760 		  (stat & (STATUS_DATA_TRANS_DONE | STATUS_WRITE_OP_DONE))) {
761 		del_timer(&host->watchdog);
762 		mxcmci_data_done(host, stat);
763 	}
764 
765 	if (host->default_irq_mask &&
766 		  (stat & (STATUS_CARD_INSERTION | STATUS_CARD_REMOVAL)))
767 		mmc_detect_change(host->mmc, msecs_to_jiffies(200));
768 
769 	return IRQ_HANDLED;
770 }
771 
772 static void mxcmci_request(struct mmc_host *mmc, struct mmc_request *req)
773 {
774 	struct mxcmci_host *host = mmc_priv(mmc);
775 	unsigned int cmdat = host->cmdat;
776 	int error;
777 
778 	WARN_ON(host->req != NULL);
779 
780 	host->req = req;
781 	host->cmdat &= ~CMD_DAT_CONT_INIT;
782 
783 	if (host->dma)
784 		host->do_dma = 1;
785 
786 	if (req->data) {
787 		error = mxcmci_setup_data(host, req->data);
788 		if (error) {
789 			req->cmd->error = error;
790 			goto out;
791 		}
792 
793 
794 		cmdat |= CMD_DAT_CONT_DATA_ENABLE;
795 
796 		if (req->data->flags & MMC_DATA_WRITE)
797 			cmdat |= CMD_DAT_CONT_WRITE;
798 	}
799 
800 	error = mxcmci_start_cmd(host, req->cmd, cmdat);
801 
802 out:
803 	if (error)
804 		mxcmci_finish_request(host, req);
805 }
806 
807 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios)
808 {
809 	unsigned int divider;
810 	int prescaler = 0;
811 	unsigned int clk_in = clk_get_rate(host->clk_per);
812 
813 	while (prescaler <= 0x800) {
814 		for (divider = 1; divider <= 0xF; divider++) {
815 			int x;
816 
817 			x = (clk_in / (divider + 1));
818 
819 			if (prescaler)
820 				x /= (prescaler * 2);
821 
822 			if (x <= clk_ios)
823 				break;
824 		}
825 		if (divider < 0x10)
826 			break;
827 
828 		if (prescaler == 0)
829 			prescaler = 1;
830 		else
831 			prescaler <<= 1;
832 	}
833 
834 	mxcmci_writew(host, (prescaler << 4) | divider, MMC_REG_CLK_RATE);
835 
836 	dev_dbg(mmc_dev(host->mmc), "scaler: %d divider: %d in: %d out: %d\n",
837 			prescaler, divider, clk_in, clk_ios);
838 }
839 
840 static int mxcmci_setup_dma(struct mmc_host *mmc)
841 {
842 	struct mxcmci_host *host = mmc_priv(mmc);
843 	struct dma_slave_config *config = &host->dma_slave_config;
844 
845 	config->dst_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
846 	config->src_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
847 	config->dst_addr_width = 4;
848 	config->src_addr_width = 4;
849 	config->dst_maxburst = host->burstlen;
850 	config->src_maxburst = host->burstlen;
851 	config->device_fc = false;
852 
853 	return dmaengine_slave_config(host->dma, config);
854 }
855 
856 static void mxcmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
857 {
858 	struct mxcmci_host *host = mmc_priv(mmc);
859 	int burstlen, ret;
860 
861 	/*
862 	 * use burstlen of 64 (16 words) in 4 bit mode (--> reg value  0)
863 	 * use burstlen of 16 (4 words) in 1 bit mode (--> reg value 16)
864 	 */
865 	if (ios->bus_width == MMC_BUS_WIDTH_4)
866 		burstlen = 16;
867 	else
868 		burstlen = 4;
869 
870 	if (mxcmci_use_dma(host) && burstlen != host->burstlen) {
871 		host->burstlen = burstlen;
872 		ret = mxcmci_setup_dma(mmc);
873 		if (ret) {
874 			dev_err(mmc_dev(host->mmc),
875 				"failed to config DMA channel. Falling back to PIO\n");
876 			dma_release_channel(host->dma);
877 			host->do_dma = 0;
878 			host->dma = NULL;
879 		}
880 	}
881 
882 	if (ios->bus_width == MMC_BUS_WIDTH_4)
883 		host->cmdat |= CMD_DAT_CONT_BUS_WIDTH_4;
884 	else
885 		host->cmdat &= ~CMD_DAT_CONT_BUS_WIDTH_4;
886 
887 	if (host->power_mode != ios->power_mode) {
888 		host->power_mode = ios->power_mode;
889 		mxcmci_set_power(host, ios->vdd);
890 
891 		if (ios->power_mode == MMC_POWER_ON)
892 			host->cmdat |= CMD_DAT_CONT_INIT;
893 	}
894 
895 	if (ios->clock) {
896 		mxcmci_set_clk_rate(host, ios->clock);
897 		mxcmci_writew(host, STR_STP_CLK_START_CLK, MMC_REG_STR_STP_CLK);
898 	} else {
899 		mxcmci_writew(host, STR_STP_CLK_STOP_CLK, MMC_REG_STR_STP_CLK);
900 	}
901 
902 	host->clock = ios->clock;
903 }
904 
905 static irqreturn_t mxcmci_detect_irq(int irq, void *data)
906 {
907 	struct mmc_host *mmc = data;
908 
909 	dev_dbg(mmc_dev(mmc), "%s\n", __func__);
910 
911 	mmc_detect_change(mmc, msecs_to_jiffies(250));
912 	return IRQ_HANDLED;
913 }
914 
915 static int mxcmci_get_ro(struct mmc_host *mmc)
916 {
917 	struct mxcmci_host *host = mmc_priv(mmc);
918 
919 	if (host->pdata && host->pdata->get_ro)
920 		return !!host->pdata->get_ro(mmc_dev(mmc));
921 	/*
922 	 * If board doesn't support read only detection (no mmc_gpio
923 	 * context or gpio is invalid), then let the mmc core decide
924 	 * what to do.
925 	 */
926 	return mmc_gpio_get_ro(mmc);
927 }
928 
929 static void mxcmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
930 {
931 	struct mxcmci_host *host = mmc_priv(mmc);
932 	unsigned long flags;
933 	u32 int_cntr;
934 
935 	spin_lock_irqsave(&host->lock, flags);
936 	host->use_sdio = enable;
937 	int_cntr = mxcmci_readl(host, MMC_REG_INT_CNTR);
938 
939 	if (enable)
940 		int_cntr |= INT_SDIO_IRQ_EN;
941 	else
942 		int_cntr &= ~INT_SDIO_IRQ_EN;
943 
944 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
945 	spin_unlock_irqrestore(&host->lock, flags);
946 }
947 
948 static void mxcmci_init_card(struct mmc_host *host, struct mmc_card *card)
949 {
950 	struct mxcmci_host *mxcmci = mmc_priv(host);
951 
952 	/*
953 	 * MX3 SoCs have a silicon bug which corrupts CRC calculation of
954 	 * multi-block transfers when connected SDIO peripheral doesn't
955 	 * drive the BUSY line as required by the specs.
956 	 * One way to prevent this is to only allow 1-bit transfers.
957 	 */
958 
959 	if (is_imx31_mmc(mxcmci) && card->type == MMC_TYPE_SDIO)
960 		host->caps &= ~MMC_CAP_4_BIT_DATA;
961 	else
962 		host->caps |= MMC_CAP_4_BIT_DATA;
963 }
964 
965 static bool filter(struct dma_chan *chan, void *param)
966 {
967 	struct mxcmci_host *host = param;
968 
969 	if (!imx_dma_is_general_purpose(chan))
970 		return false;
971 
972 	chan->private = &host->dma_data;
973 
974 	return true;
975 }
976 
977 static void mxcmci_watchdog(unsigned long data)
978 {
979 	struct mmc_host *mmc = (struct mmc_host *)data;
980 	struct mxcmci_host *host = mmc_priv(mmc);
981 	struct mmc_request *req = host->req;
982 	unsigned int stat = mxcmci_readl(host, MMC_REG_STATUS);
983 
984 	if (host->dma_dir == DMA_FROM_DEVICE) {
985 		dmaengine_terminate_all(host->dma);
986 		dev_err(mmc_dev(host->mmc),
987 			"%s: read time out (status = 0x%08x)\n",
988 			__func__, stat);
989 	} else {
990 		dev_err(mmc_dev(host->mmc),
991 			"%s: write time out (status = 0x%08x)\n",
992 			__func__, stat);
993 		mxcmci_softreset(host);
994 	}
995 
996 	/* Mark transfer as erroneus and inform the upper layers */
997 
998 	if (host->data)
999 		host->data->error = -ETIMEDOUT;
1000 	host->req = NULL;
1001 	host->cmd = NULL;
1002 	host->data = NULL;
1003 	mmc_request_done(host->mmc, req);
1004 }
1005 
1006 static const struct mmc_host_ops mxcmci_ops = {
1007 	.request		= mxcmci_request,
1008 	.set_ios		= mxcmci_set_ios,
1009 	.get_ro			= mxcmci_get_ro,
1010 	.enable_sdio_irq	= mxcmci_enable_sdio_irq,
1011 	.init_card		= mxcmci_init_card,
1012 };
1013 
1014 static int mxcmci_probe(struct platform_device *pdev)
1015 {
1016 	struct mmc_host *mmc;
1017 	struct mxcmci_host *host;
1018 	struct resource *res;
1019 	int ret = 0, irq;
1020 	bool dat3_card_detect = false;
1021 	dma_cap_mask_t mask;
1022 	const struct of_device_id *of_id;
1023 	struct imxmmc_platform_data *pdata = pdev->dev.platform_data;
1024 
1025 	pr_info("i.MX/MPC512x SDHC driver\n");
1026 
1027 	of_id = of_match_device(mxcmci_of_match, &pdev->dev);
1028 
1029 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1030 	irq = platform_get_irq(pdev, 0);
1031 	if (irq < 0)
1032 		return -EINVAL;
1033 
1034 	mmc = mmc_alloc_host(sizeof(*host), &pdev->dev);
1035 	if (!mmc)
1036 		return -ENOMEM;
1037 
1038 	host = mmc_priv(mmc);
1039 
1040 	host->base = devm_ioremap_resource(&pdev->dev, res);
1041 	if (IS_ERR(host->base)) {
1042 		ret = PTR_ERR(host->base);
1043 		goto out_free;
1044 	}
1045 
1046 	host->phys_base = res->start;
1047 
1048 	ret = mmc_of_parse(mmc);
1049 	if (ret)
1050 		goto out_free;
1051 	mmc->ops = &mxcmci_ops;
1052 
1053 	/* For devicetree parsing, the bus width is read from devicetree */
1054 	if (pdata)
1055 		mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
1056 	else
1057 		mmc->caps |= MMC_CAP_SDIO_IRQ;
1058 
1059 	/* MMC core transfer sizes tunable parameters */
1060 	mmc->max_blk_size = 2048;
1061 	mmc->max_blk_count = 65535;
1062 	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
1063 	mmc->max_seg_size = mmc->max_req_size;
1064 
1065 	if (of_id) {
1066 		const struct platform_device_id *id_entry = of_id->data;
1067 		host->devtype = id_entry->driver_data;
1068 	} else {
1069 		host->devtype = pdev->id_entry->driver_data;
1070 	}
1071 
1072 	/* adjust max_segs after devtype detection */
1073 	if (!is_mpc512x_mmc(host))
1074 		mmc->max_segs = 64;
1075 
1076 	host->mmc = mmc;
1077 	host->pdata = pdata;
1078 	spin_lock_init(&host->lock);
1079 
1080 	if (pdata)
1081 		dat3_card_detect = pdata->dat3_card_detect;
1082 	else if (!(mmc->caps & MMC_CAP_NONREMOVABLE)
1083 			&& !of_property_read_bool(pdev->dev.of_node, "cd-gpios"))
1084 		dat3_card_detect = true;
1085 
1086 	ret = mmc_regulator_get_supply(mmc);
1087 	if (ret) {
1088 		if (pdata && ret != -EPROBE_DEFER)
1089 			mmc->ocr_avail = pdata->ocr_avail ? :
1090 				MMC_VDD_32_33 | MMC_VDD_33_34;
1091 		else
1092 			goto out_free;
1093 	}
1094 
1095 	if (dat3_card_detect)
1096 		host->default_irq_mask =
1097 			INT_CARD_INSERTION_EN | INT_CARD_REMOVAL_EN;
1098 	else
1099 		host->default_irq_mask = 0;
1100 
1101 	host->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1102 	if (IS_ERR(host->clk_ipg)) {
1103 		ret = PTR_ERR(host->clk_ipg);
1104 		goto out_free;
1105 	}
1106 
1107 	host->clk_per = devm_clk_get(&pdev->dev, "per");
1108 	if (IS_ERR(host->clk_per)) {
1109 		ret = PTR_ERR(host->clk_per);
1110 		goto out_free;
1111 	}
1112 
1113 	clk_prepare_enable(host->clk_per);
1114 	clk_prepare_enable(host->clk_ipg);
1115 
1116 	mxcmci_softreset(host);
1117 
1118 	host->rev_no = mxcmci_readw(host, MMC_REG_REV_NO);
1119 	if (host->rev_no != 0x400) {
1120 		ret = -ENODEV;
1121 		dev_err(mmc_dev(host->mmc), "wrong rev.no. 0x%08x. aborting.\n",
1122 			host->rev_no);
1123 		goto out_clk_put;
1124 	}
1125 
1126 	mmc->f_min = clk_get_rate(host->clk_per) >> 16;
1127 	mmc->f_max = clk_get_rate(host->clk_per) >> 1;
1128 
1129 	/* recommended in data sheet */
1130 	mxcmci_writew(host, 0x2db4, MMC_REG_READ_TO);
1131 
1132 	mxcmci_writel(host, host->default_irq_mask, MMC_REG_INT_CNTR);
1133 
1134 	if (!host->pdata) {
1135 		host->dma = dma_request_slave_channel(&pdev->dev, "rx-tx");
1136 	} else {
1137 		res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1138 		if (res) {
1139 			host->dmareq = res->start;
1140 			host->dma_data.peripheral_type = IMX_DMATYPE_SDHC;
1141 			host->dma_data.priority = DMA_PRIO_LOW;
1142 			host->dma_data.dma_request = host->dmareq;
1143 			dma_cap_zero(mask);
1144 			dma_cap_set(DMA_SLAVE, mask);
1145 			host->dma = dma_request_channel(mask, filter, host);
1146 		}
1147 	}
1148 	if (host->dma)
1149 		mmc->max_seg_size = dma_get_max_seg_size(
1150 				host->dma->device->dev);
1151 	else
1152 		dev_info(mmc_dev(host->mmc), "dma not available. Using PIO\n");
1153 
1154 	INIT_WORK(&host->datawork, mxcmci_datawork);
1155 
1156 	ret = devm_request_irq(&pdev->dev, irq, mxcmci_irq, 0,
1157 			       dev_name(&pdev->dev), host);
1158 	if (ret)
1159 		goto out_free_dma;
1160 
1161 	platform_set_drvdata(pdev, mmc);
1162 
1163 	if (host->pdata && host->pdata->init) {
1164 		ret = host->pdata->init(&pdev->dev, mxcmci_detect_irq,
1165 				host->mmc);
1166 		if (ret)
1167 			goto out_free_dma;
1168 	}
1169 
1170 	init_timer(&host->watchdog);
1171 	host->watchdog.function = &mxcmci_watchdog;
1172 	host->watchdog.data = (unsigned long)mmc;
1173 
1174 	mmc_add_host(mmc);
1175 
1176 	return 0;
1177 
1178 out_free_dma:
1179 	if (host->dma)
1180 		dma_release_channel(host->dma);
1181 
1182 out_clk_put:
1183 	clk_disable_unprepare(host->clk_per);
1184 	clk_disable_unprepare(host->clk_ipg);
1185 
1186 out_free:
1187 	mmc_free_host(mmc);
1188 
1189 	return ret;
1190 }
1191 
1192 static int mxcmci_remove(struct platform_device *pdev)
1193 {
1194 	struct mmc_host *mmc = platform_get_drvdata(pdev);
1195 	struct mxcmci_host *host = mmc_priv(mmc);
1196 
1197 	mmc_remove_host(mmc);
1198 
1199 	if (host->pdata && host->pdata->exit)
1200 		host->pdata->exit(&pdev->dev, mmc);
1201 
1202 	if (host->dma)
1203 		dma_release_channel(host->dma);
1204 
1205 	clk_disable_unprepare(host->clk_per);
1206 	clk_disable_unprepare(host->clk_ipg);
1207 
1208 	mmc_free_host(mmc);
1209 
1210 	return 0;
1211 }
1212 
1213 static int __maybe_unused mxcmci_suspend(struct device *dev)
1214 {
1215 	struct mmc_host *mmc = dev_get_drvdata(dev);
1216 	struct mxcmci_host *host = mmc_priv(mmc);
1217 
1218 	clk_disable_unprepare(host->clk_per);
1219 	clk_disable_unprepare(host->clk_ipg);
1220 	return 0;
1221 }
1222 
1223 static int __maybe_unused mxcmci_resume(struct device *dev)
1224 {
1225 	struct mmc_host *mmc = dev_get_drvdata(dev);
1226 	struct mxcmci_host *host = mmc_priv(mmc);
1227 
1228 	clk_prepare_enable(host->clk_per);
1229 	clk_prepare_enable(host->clk_ipg);
1230 	return 0;
1231 }
1232 
1233 static SIMPLE_DEV_PM_OPS(mxcmci_pm_ops, mxcmci_suspend, mxcmci_resume);
1234 
1235 static struct platform_driver mxcmci_driver = {
1236 	.probe		= mxcmci_probe,
1237 	.remove		= mxcmci_remove,
1238 	.id_table	= mxcmci_devtype,
1239 	.driver		= {
1240 		.name		= DRIVER_NAME,
1241 		.owner		= THIS_MODULE,
1242 		.pm	= &mxcmci_pm_ops,
1243 		.of_match_table	= mxcmci_of_match,
1244 	}
1245 };
1246 
1247 module_platform_driver(mxcmci_driver);
1248 
1249 MODULE_DESCRIPTION("i.MX Multimedia Card Interface Driver");
1250 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1251 MODULE_LICENSE("GPL");
1252 MODULE_ALIAS("platform:mxc-mmc");
1253