xref: /linux/drivers/mmc/host/mxcmmc.c (revision 96ac6d435100450f0565708d9b885ea2a7400e0a)
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/highmem.h>
25 #include <linux/interrupt.h>
26 #include <linux/irq.h>
27 #include <linux/blkdev.h>
28 #include <linux/dma-mapping.h>
29 #include <linux/mmc/host.h>
30 #include <linux/mmc/card.h>
31 #include <linux/delay.h>
32 #include <linux/clk.h>
33 #include <linux/io.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/mmc/slot-gpio.h>
41 
42 #include <asm/dma.h>
43 #include <asm/irq.h>
44 #include <linux/platform_data/mmc-mxcmmc.h>
45 
46 #include <linux/platform_data/dma-imx.h>
47 
48 #define DRIVER_NAME "mxc-mmc"
49 #define MXCMCI_TIMEOUT_MS 10000
50 
51 #define MMC_REG_STR_STP_CLK		0x00
52 #define MMC_REG_STATUS			0x04
53 #define MMC_REG_CLK_RATE		0x08
54 #define MMC_REG_CMD_DAT_CONT		0x0C
55 #define MMC_REG_RES_TO			0x10
56 #define MMC_REG_READ_TO			0x14
57 #define MMC_REG_BLK_LEN			0x18
58 #define MMC_REG_NOB			0x1C
59 #define MMC_REG_REV_NO			0x20
60 #define MMC_REG_INT_CNTR		0x24
61 #define MMC_REG_CMD			0x28
62 #define MMC_REG_ARG			0x2C
63 #define MMC_REG_RES_FIFO		0x34
64 #define MMC_REG_BUFFER_ACCESS		0x38
65 
66 #define STR_STP_CLK_RESET               (1 << 3)
67 #define STR_STP_CLK_START_CLK           (1 << 1)
68 #define STR_STP_CLK_STOP_CLK            (1 << 0)
69 
70 #define STATUS_CARD_INSERTION		(1 << 31)
71 #define STATUS_CARD_REMOVAL		(1 << 30)
72 #define STATUS_YBUF_EMPTY		(1 << 29)
73 #define STATUS_XBUF_EMPTY		(1 << 28)
74 #define STATUS_YBUF_FULL		(1 << 27)
75 #define STATUS_XBUF_FULL		(1 << 26)
76 #define STATUS_BUF_UND_RUN		(1 << 25)
77 #define STATUS_BUF_OVFL			(1 << 24)
78 #define STATUS_SDIO_INT_ACTIVE		(1 << 14)
79 #define STATUS_END_CMD_RESP		(1 << 13)
80 #define STATUS_WRITE_OP_DONE		(1 << 12)
81 #define STATUS_DATA_TRANS_DONE		(1 << 11)
82 #define STATUS_READ_OP_DONE		(1 << 11)
83 #define STATUS_WR_CRC_ERROR_CODE_MASK	(3 << 10)
84 #define STATUS_CARD_BUS_CLK_RUN		(1 << 8)
85 #define STATUS_BUF_READ_RDY		(1 << 7)
86 #define STATUS_BUF_WRITE_RDY		(1 << 6)
87 #define STATUS_RESP_CRC_ERR		(1 << 5)
88 #define STATUS_CRC_READ_ERR		(1 << 3)
89 #define STATUS_CRC_WRITE_ERR		(1 << 2)
90 #define STATUS_TIME_OUT_RESP		(1 << 1)
91 #define STATUS_TIME_OUT_READ		(1 << 0)
92 #define STATUS_ERR_MASK			0x2f
93 
94 #define CMD_DAT_CONT_CMD_RESP_LONG_OFF	(1 << 12)
95 #define CMD_DAT_CONT_STOP_READWAIT	(1 << 11)
96 #define CMD_DAT_CONT_START_READWAIT	(1 << 10)
97 #define CMD_DAT_CONT_BUS_WIDTH_4	(2 << 8)
98 #define CMD_DAT_CONT_INIT		(1 << 7)
99 #define CMD_DAT_CONT_WRITE		(1 << 4)
100 #define CMD_DAT_CONT_DATA_ENABLE	(1 << 3)
101 #define CMD_DAT_CONT_RESPONSE_48BIT_CRC	(1 << 0)
102 #define CMD_DAT_CONT_RESPONSE_136BIT	(2 << 0)
103 #define CMD_DAT_CONT_RESPONSE_48BIT	(3 << 0)
104 
105 #define INT_SDIO_INT_WKP_EN		(1 << 18)
106 #define INT_CARD_INSERTION_WKP_EN	(1 << 17)
107 #define INT_CARD_REMOVAL_WKP_EN		(1 << 16)
108 #define INT_CARD_INSERTION_EN		(1 << 15)
109 #define INT_CARD_REMOVAL_EN		(1 << 14)
110 #define INT_SDIO_IRQ_EN			(1 << 13)
111 #define INT_DAT0_EN			(1 << 12)
112 #define INT_BUF_READ_EN			(1 << 4)
113 #define INT_BUF_WRITE_EN		(1 << 3)
114 #define INT_END_CMD_RES_EN		(1 << 2)
115 #define INT_WRITE_OP_DONE_EN		(1 << 1)
116 #define INT_READ_OP_EN			(1 << 0)
117 
118 enum mxcmci_type {
119 	IMX21_MMC,
120 	IMX31_MMC,
121 	MPC512X_MMC,
122 };
123 
124 struct mxcmci_host {
125 	struct mmc_host		*mmc;
126 	void __iomem		*base;
127 	dma_addr_t		phys_base;
128 	int			detect_irq;
129 	struct dma_chan		*dma;
130 	struct dma_async_tx_descriptor *desc;
131 	int			do_dma;
132 	int			default_irq_mask;
133 	int			use_sdio;
134 	unsigned int		power_mode;
135 	struct imxmmc_platform_data *pdata;
136 
137 	struct mmc_request	*req;
138 	struct mmc_command	*cmd;
139 	struct mmc_data		*data;
140 
141 	unsigned int		datasize;
142 	unsigned int		dma_dir;
143 
144 	u16			rev_no;
145 	unsigned int		cmdat;
146 
147 	struct clk		*clk_ipg;
148 	struct clk		*clk_per;
149 
150 	int			clock;
151 
152 	struct work_struct	datawork;
153 	spinlock_t		lock;
154 
155 	int			burstlen;
156 	int			dmareq;
157 	struct dma_slave_config dma_slave_config;
158 	struct imx_dma_data	dma_data;
159 
160 	struct timer_list	watchdog;
161 	enum mxcmci_type	devtype;
162 };
163 
164 static const struct platform_device_id mxcmci_devtype[] = {
165 	{
166 		.name = "imx21-mmc",
167 		.driver_data = IMX21_MMC,
168 	}, {
169 		.name = "imx31-mmc",
170 		.driver_data = IMX31_MMC,
171 	}, {
172 		.name = "mpc512x-sdhc",
173 		.driver_data = MPC512X_MMC,
174 	}, {
175 		/* sentinel */
176 	}
177 };
178 MODULE_DEVICE_TABLE(platform, mxcmci_devtype);
179 
180 static const struct of_device_id mxcmci_of_match[] = {
181 	{
182 		.compatible = "fsl,imx21-mmc",
183 		.data = &mxcmci_devtype[IMX21_MMC],
184 	}, {
185 		.compatible = "fsl,imx31-mmc",
186 		.data = &mxcmci_devtype[IMX31_MMC],
187 	}, {
188 		.compatible = "fsl,mpc5121-sdhc",
189 		.data = &mxcmci_devtype[MPC512X_MMC],
190 	}, {
191 		/* sentinel */
192 	}
193 };
194 MODULE_DEVICE_TABLE(of, mxcmci_of_match);
195 
196 static inline int is_imx31_mmc(struct mxcmci_host *host)
197 {
198 	return host->devtype == IMX31_MMC;
199 }
200 
201 static inline int is_mpc512x_mmc(struct mxcmci_host *host)
202 {
203 	return host->devtype == MPC512X_MMC;
204 }
205 
206 static inline u32 mxcmci_readl(struct mxcmci_host *host, int reg)
207 {
208 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
209 		return ioread32be(host->base + reg);
210 	else
211 		return readl(host->base + reg);
212 }
213 
214 static inline void mxcmci_writel(struct mxcmci_host *host, u32 val, int reg)
215 {
216 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
217 		iowrite32be(val, host->base + reg);
218 	else
219 		writel(val, host->base + reg);
220 }
221 
222 static inline u16 mxcmci_readw(struct mxcmci_host *host, int reg)
223 {
224 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
225 		return ioread32be(host->base + reg);
226 	else
227 		return readw(host->base + reg);
228 }
229 
230 static inline void mxcmci_writew(struct mxcmci_host *host, u16 val, int reg)
231 {
232 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
233 		iowrite32be(val, host->base + reg);
234 	else
235 		writew(val, host->base + reg);
236 }
237 
238 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios);
239 
240 static void mxcmci_set_power(struct mxcmci_host *host, unsigned int vdd)
241 {
242 	if (!IS_ERR(host->mmc->supply.vmmc)) {
243 		if (host->power_mode == MMC_POWER_UP)
244 			mmc_regulator_set_ocr(host->mmc,
245 					      host->mmc->supply.vmmc, vdd);
246 		else if (host->power_mode == MMC_POWER_OFF)
247 			mmc_regulator_set_ocr(host->mmc,
248 					      host->mmc->supply.vmmc, 0);
249 	}
250 
251 	if (host->pdata && host->pdata->setpower)
252 		host->pdata->setpower(mmc_dev(host->mmc), vdd);
253 }
254 
255 static inline int mxcmci_use_dma(struct mxcmci_host *host)
256 {
257 	return host->do_dma;
258 }
259 
260 static void mxcmci_softreset(struct mxcmci_host *host)
261 {
262 	int i;
263 
264 	dev_dbg(mmc_dev(host->mmc), "mxcmci_softreset\n");
265 
266 	/* reset sequence */
267 	mxcmci_writew(host, STR_STP_CLK_RESET, MMC_REG_STR_STP_CLK);
268 	mxcmci_writew(host, STR_STP_CLK_RESET | STR_STP_CLK_START_CLK,
269 			MMC_REG_STR_STP_CLK);
270 
271 	for (i = 0; i < 8; i++)
272 		mxcmci_writew(host, STR_STP_CLK_START_CLK, MMC_REG_STR_STP_CLK);
273 
274 	mxcmci_writew(host, 0xff, MMC_REG_RES_TO);
275 }
276 
277 #if IS_ENABLED(CONFIG_PPC_MPC512x)
278 static inline void buffer_swap32(u32 *buf, int len)
279 {
280 	int i;
281 
282 	for (i = 0; i < ((len + 3) / 4); i++) {
283 		*buf = swab32(*buf);
284 		buf++;
285 	}
286 }
287 
288 static void mxcmci_swap_buffers(struct mmc_data *data)
289 {
290 	struct scatterlist *sg;
291 	int i;
292 
293 	for_each_sg(data->sg, sg, data->sg_len, i)
294 		buffer_swap32(sg_virt(sg), sg->length);
295 }
296 #else
297 static inline void mxcmci_swap_buffers(struct mmc_data *data) {}
298 #endif
299 
300 static int mxcmci_setup_data(struct mxcmci_host *host, struct mmc_data *data)
301 {
302 	unsigned int nob = data->blocks;
303 	unsigned int blksz = data->blksz;
304 	unsigned int datasize = nob * blksz;
305 	struct scatterlist *sg;
306 	enum dma_transfer_direction slave_dirn;
307 	int i, nents;
308 
309 	host->data = data;
310 	data->bytes_xfered = 0;
311 
312 	mxcmci_writew(host, nob, MMC_REG_NOB);
313 	mxcmci_writew(host, blksz, MMC_REG_BLK_LEN);
314 	host->datasize = datasize;
315 
316 	if (!mxcmci_use_dma(host))
317 		return 0;
318 
319 	for_each_sg(data->sg, sg, data->sg_len, i) {
320 		if (sg->offset & 3 || sg->length & 3 || sg->length < 512) {
321 			host->do_dma = 0;
322 			return 0;
323 		}
324 	}
325 
326 	if (data->flags & MMC_DATA_READ) {
327 		host->dma_dir = DMA_FROM_DEVICE;
328 		slave_dirn = DMA_DEV_TO_MEM;
329 	} else {
330 		host->dma_dir = DMA_TO_DEVICE;
331 		slave_dirn = DMA_MEM_TO_DEV;
332 
333 		mxcmci_swap_buffers(data);
334 	}
335 
336 	nents = dma_map_sg(host->dma->device->dev, data->sg,
337 				     data->sg_len,  host->dma_dir);
338 	if (nents != data->sg_len)
339 		return -EINVAL;
340 
341 	host->desc = dmaengine_prep_slave_sg(host->dma,
342 		data->sg, data->sg_len, slave_dirn,
343 		DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
344 
345 	if (!host->desc) {
346 		dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
347 				host->dma_dir);
348 		host->do_dma = 0;
349 		return 0; /* Fall back to PIO */
350 	}
351 	wmb();
352 
353 	dmaengine_submit(host->desc);
354 	dma_async_issue_pending(host->dma);
355 
356 	mod_timer(&host->watchdog, jiffies + msecs_to_jiffies(MXCMCI_TIMEOUT_MS));
357 
358 	return 0;
359 }
360 
361 static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat);
362 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat);
363 
364 static void mxcmci_dma_callback(void *data)
365 {
366 	struct mxcmci_host *host = data;
367 	u32 stat;
368 
369 	del_timer(&host->watchdog);
370 
371 	stat = mxcmci_readl(host, MMC_REG_STATUS);
372 
373 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
374 
375 	mxcmci_data_done(host, stat);
376 }
377 
378 static int mxcmci_start_cmd(struct mxcmci_host *host, struct mmc_command *cmd,
379 		unsigned int cmdat)
380 {
381 	u32 int_cntr = host->default_irq_mask;
382 	unsigned long flags;
383 
384 	WARN_ON(host->cmd != NULL);
385 	host->cmd = cmd;
386 
387 	switch (mmc_resp_type(cmd)) {
388 	case MMC_RSP_R1: /* short CRC, OPCODE */
389 	case MMC_RSP_R1B:/* short CRC, OPCODE, BUSY */
390 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT_CRC;
391 		break;
392 	case MMC_RSP_R2: /* long 136 bit + CRC */
393 		cmdat |= CMD_DAT_CONT_RESPONSE_136BIT;
394 		break;
395 	case MMC_RSP_R3: /* short */
396 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT;
397 		break;
398 	case MMC_RSP_NONE:
399 		break;
400 	default:
401 		dev_err(mmc_dev(host->mmc), "unhandled response type 0x%x\n",
402 				mmc_resp_type(cmd));
403 		cmd->error = -EINVAL;
404 		return -EINVAL;
405 	}
406 
407 	int_cntr = INT_END_CMD_RES_EN;
408 
409 	if (mxcmci_use_dma(host)) {
410 		if (host->dma_dir == DMA_FROM_DEVICE) {
411 			host->desc->callback = mxcmci_dma_callback;
412 			host->desc->callback_param = host;
413 		} else {
414 			int_cntr |= INT_WRITE_OP_DONE_EN;
415 		}
416 	}
417 
418 	spin_lock_irqsave(&host->lock, flags);
419 	if (host->use_sdio)
420 		int_cntr |= INT_SDIO_IRQ_EN;
421 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
422 	spin_unlock_irqrestore(&host->lock, flags);
423 
424 	mxcmci_writew(host, cmd->opcode, MMC_REG_CMD);
425 	mxcmci_writel(host, cmd->arg, MMC_REG_ARG);
426 	mxcmci_writew(host, cmdat, MMC_REG_CMD_DAT_CONT);
427 
428 	return 0;
429 }
430 
431 static void mxcmci_finish_request(struct mxcmci_host *host,
432 		struct mmc_request *req)
433 {
434 	u32 int_cntr = host->default_irq_mask;
435 	unsigned long flags;
436 
437 	spin_lock_irqsave(&host->lock, flags);
438 	if (host->use_sdio)
439 		int_cntr |= INT_SDIO_IRQ_EN;
440 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
441 	spin_unlock_irqrestore(&host->lock, flags);
442 
443 	host->req = NULL;
444 	host->cmd = NULL;
445 	host->data = NULL;
446 
447 	mmc_request_done(host->mmc, req);
448 }
449 
450 static int mxcmci_finish_data(struct mxcmci_host *host, unsigned int stat)
451 {
452 	struct mmc_data *data = host->data;
453 	int data_error;
454 
455 	if (mxcmci_use_dma(host)) {
456 		dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
457 				host->dma_dir);
458 		mxcmci_swap_buffers(data);
459 	}
460 
461 	if (stat & STATUS_ERR_MASK) {
462 		dev_dbg(mmc_dev(host->mmc), "request failed. status: 0x%08x\n",
463 				stat);
464 		if (stat & STATUS_CRC_READ_ERR) {
465 			dev_err(mmc_dev(host->mmc), "%s: -EILSEQ\n", __func__);
466 			data->error = -EILSEQ;
467 		} else if (stat & STATUS_CRC_WRITE_ERR) {
468 			u32 err_code = (stat >> 9) & 0x3;
469 			if (err_code == 2) { /* No CRC response */
470 				dev_err(mmc_dev(host->mmc),
471 					"%s: No CRC -ETIMEDOUT\n", __func__);
472 				data->error = -ETIMEDOUT;
473 			} else {
474 				dev_err(mmc_dev(host->mmc),
475 					"%s: -EILSEQ\n", __func__);
476 				data->error = -EILSEQ;
477 			}
478 		} else if (stat & STATUS_TIME_OUT_READ) {
479 			dev_err(mmc_dev(host->mmc),
480 				"%s: read -ETIMEDOUT\n", __func__);
481 			data->error = -ETIMEDOUT;
482 		} else {
483 			dev_err(mmc_dev(host->mmc), "%s: -EIO\n", __func__);
484 			data->error = -EIO;
485 		}
486 	} else {
487 		data->bytes_xfered = host->datasize;
488 	}
489 
490 	data_error = data->error;
491 
492 	host->data = NULL;
493 
494 	return data_error;
495 }
496 
497 static void mxcmci_read_response(struct mxcmci_host *host, unsigned int stat)
498 {
499 	struct mmc_command *cmd = host->cmd;
500 	int i;
501 	u32 a, b, c;
502 
503 	if (!cmd)
504 		return;
505 
506 	if (stat & STATUS_TIME_OUT_RESP) {
507 		dev_dbg(mmc_dev(host->mmc), "CMD TIMEOUT\n");
508 		cmd->error = -ETIMEDOUT;
509 	} else if (stat & STATUS_RESP_CRC_ERR && cmd->flags & MMC_RSP_CRC) {
510 		dev_dbg(mmc_dev(host->mmc), "cmd crc error\n");
511 		cmd->error = -EILSEQ;
512 	}
513 
514 	if (cmd->flags & MMC_RSP_PRESENT) {
515 		if (cmd->flags & MMC_RSP_136) {
516 			for (i = 0; i < 4; i++) {
517 				a = mxcmci_readw(host, MMC_REG_RES_FIFO);
518 				b = mxcmci_readw(host, MMC_REG_RES_FIFO);
519 				cmd->resp[i] = a << 16 | b;
520 			}
521 		} else {
522 			a = mxcmci_readw(host, MMC_REG_RES_FIFO);
523 			b = mxcmci_readw(host, MMC_REG_RES_FIFO);
524 			c = mxcmci_readw(host, MMC_REG_RES_FIFO);
525 			cmd->resp[0] = a << 24 | b << 8 | c >> 8;
526 		}
527 	}
528 }
529 
530 static int mxcmci_poll_status(struct mxcmci_host *host, u32 mask)
531 {
532 	u32 stat;
533 	unsigned long timeout = jiffies + HZ;
534 
535 	do {
536 		stat = mxcmci_readl(host, MMC_REG_STATUS);
537 		if (stat & STATUS_ERR_MASK)
538 			return stat;
539 		if (time_after(jiffies, timeout)) {
540 			mxcmci_softreset(host);
541 			mxcmci_set_clk_rate(host, host->clock);
542 			return STATUS_TIME_OUT_READ;
543 		}
544 		if (stat & mask)
545 			return 0;
546 		cpu_relax();
547 	} while (1);
548 }
549 
550 static int mxcmci_pull(struct mxcmci_host *host, void *_buf, int bytes)
551 {
552 	unsigned int stat;
553 	u32 *buf = _buf;
554 
555 	while (bytes > 3) {
556 		stat = mxcmci_poll_status(host,
557 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
558 		if (stat)
559 			return stat;
560 		*buf++ = cpu_to_le32(mxcmci_readl(host, MMC_REG_BUFFER_ACCESS));
561 		bytes -= 4;
562 	}
563 
564 	if (bytes) {
565 		u8 *b = (u8 *)buf;
566 		u32 tmp;
567 
568 		stat = mxcmci_poll_status(host,
569 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
570 		if (stat)
571 			return stat;
572 		tmp = cpu_to_le32(mxcmci_readl(host, MMC_REG_BUFFER_ACCESS));
573 		memcpy(b, &tmp, bytes);
574 	}
575 
576 	return 0;
577 }
578 
579 static int mxcmci_push(struct mxcmci_host *host, void *_buf, int bytes)
580 {
581 	unsigned int stat;
582 	u32 *buf = _buf;
583 
584 	while (bytes > 3) {
585 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
586 		if (stat)
587 			return stat;
588 		mxcmci_writel(host, cpu_to_le32(*buf++), MMC_REG_BUFFER_ACCESS);
589 		bytes -= 4;
590 	}
591 
592 	if (bytes) {
593 		u8 *b = (u8 *)buf;
594 		u32 tmp;
595 
596 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
597 		if (stat)
598 			return stat;
599 
600 		memcpy(&tmp, b, bytes);
601 		mxcmci_writel(host, cpu_to_le32(tmp), MMC_REG_BUFFER_ACCESS);
602 	}
603 
604 	return mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
605 }
606 
607 static int mxcmci_transfer_data(struct mxcmci_host *host)
608 {
609 	struct mmc_data *data = host->req->data;
610 	struct scatterlist *sg;
611 	int stat, i;
612 
613 	host->data = data;
614 	host->datasize = 0;
615 
616 	if (data->flags & MMC_DATA_READ) {
617 		for_each_sg(data->sg, sg, data->sg_len, i) {
618 			stat = mxcmci_pull(host, sg_virt(sg), sg->length);
619 			if (stat)
620 				return stat;
621 			host->datasize += sg->length;
622 		}
623 	} else {
624 		for_each_sg(data->sg, sg, data->sg_len, i) {
625 			stat = mxcmci_push(host, sg_virt(sg), sg->length);
626 			if (stat)
627 				return stat;
628 			host->datasize += sg->length;
629 		}
630 		stat = mxcmci_poll_status(host, STATUS_WRITE_OP_DONE);
631 		if (stat)
632 			return stat;
633 	}
634 	return 0;
635 }
636 
637 static void mxcmci_datawork(struct work_struct *work)
638 {
639 	struct mxcmci_host *host = container_of(work, struct mxcmci_host,
640 						  datawork);
641 	int datastat = mxcmci_transfer_data(host);
642 
643 	mxcmci_writel(host, STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE,
644 		MMC_REG_STATUS);
645 	mxcmci_finish_data(host, datastat);
646 
647 	if (host->req->stop) {
648 		if (mxcmci_start_cmd(host, host->req->stop, 0)) {
649 			mxcmci_finish_request(host, host->req);
650 			return;
651 		}
652 	} else {
653 		mxcmci_finish_request(host, host->req);
654 	}
655 }
656 
657 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat)
658 {
659 	struct mmc_request *req;
660 	int data_error;
661 	unsigned long flags;
662 
663 	spin_lock_irqsave(&host->lock, flags);
664 
665 	if (!host->data) {
666 		spin_unlock_irqrestore(&host->lock, flags);
667 		return;
668 	}
669 
670 	if (!host->req) {
671 		spin_unlock_irqrestore(&host->lock, flags);
672 		return;
673 	}
674 
675 	req = host->req;
676 	if (!req->stop)
677 		host->req = NULL; /* we will handle finish req below */
678 
679 	data_error = mxcmci_finish_data(host, stat);
680 
681 	spin_unlock_irqrestore(&host->lock, flags);
682 
683 	if (data_error)
684 		return;
685 
686 	mxcmci_read_response(host, stat);
687 	host->cmd = NULL;
688 
689 	if (req->stop) {
690 		if (mxcmci_start_cmd(host, req->stop, 0)) {
691 			mxcmci_finish_request(host, req);
692 			return;
693 		}
694 	} else {
695 		mxcmci_finish_request(host, req);
696 	}
697 }
698 
699 static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat)
700 {
701 	mxcmci_read_response(host, stat);
702 	host->cmd = NULL;
703 
704 	if (!host->data && host->req) {
705 		mxcmci_finish_request(host, host->req);
706 		return;
707 	}
708 
709 	/* For the DMA case the DMA engine handles the data transfer
710 	 * automatically. For non DMA we have to do it ourselves.
711 	 * Don't do it in interrupt context though.
712 	 */
713 	if (!mxcmci_use_dma(host) && host->data)
714 		schedule_work(&host->datawork);
715 
716 }
717 
718 static irqreturn_t mxcmci_irq(int irq, void *devid)
719 {
720 	struct mxcmci_host *host = devid;
721 	bool sdio_irq;
722 	u32 stat;
723 
724 	stat = mxcmci_readl(host, MMC_REG_STATUS);
725 	mxcmci_writel(host,
726 		stat & ~(STATUS_SDIO_INT_ACTIVE | STATUS_DATA_TRANS_DONE |
727 			 STATUS_WRITE_OP_DONE),
728 		MMC_REG_STATUS);
729 
730 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
731 
732 	spin_lock(&host->lock);
733 	sdio_irq = (stat & STATUS_SDIO_INT_ACTIVE) && host->use_sdio;
734 	spin_unlock(&host->lock);
735 
736 	if (mxcmci_use_dma(host) && (stat & (STATUS_WRITE_OP_DONE)))
737 		mxcmci_writel(host, STATUS_WRITE_OP_DONE, MMC_REG_STATUS);
738 
739 	if (sdio_irq) {
740 		mxcmci_writel(host, STATUS_SDIO_INT_ACTIVE, MMC_REG_STATUS);
741 		mmc_signal_sdio_irq(host->mmc);
742 	}
743 
744 	if (stat & STATUS_END_CMD_RESP)
745 		mxcmci_cmd_done(host, stat);
746 
747 	if (mxcmci_use_dma(host) && (stat & STATUS_WRITE_OP_DONE)) {
748 		del_timer(&host->watchdog);
749 		mxcmci_data_done(host, stat);
750 	}
751 
752 	if (host->default_irq_mask &&
753 		  (stat & (STATUS_CARD_INSERTION | STATUS_CARD_REMOVAL)))
754 		mmc_detect_change(host->mmc, msecs_to_jiffies(200));
755 
756 	return IRQ_HANDLED;
757 }
758 
759 static void mxcmci_request(struct mmc_host *mmc, struct mmc_request *req)
760 {
761 	struct mxcmci_host *host = mmc_priv(mmc);
762 	unsigned int cmdat = host->cmdat;
763 	int error;
764 
765 	WARN_ON(host->req != NULL);
766 
767 	host->req = req;
768 	host->cmdat &= ~CMD_DAT_CONT_INIT;
769 
770 	if (host->dma)
771 		host->do_dma = 1;
772 
773 	if (req->data) {
774 		error = mxcmci_setup_data(host, req->data);
775 		if (error) {
776 			req->cmd->error = error;
777 			goto out;
778 		}
779 
780 
781 		cmdat |= CMD_DAT_CONT_DATA_ENABLE;
782 
783 		if (req->data->flags & MMC_DATA_WRITE)
784 			cmdat |= CMD_DAT_CONT_WRITE;
785 	}
786 
787 	error = mxcmci_start_cmd(host, req->cmd, cmdat);
788 
789 out:
790 	if (error)
791 		mxcmci_finish_request(host, req);
792 }
793 
794 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios)
795 {
796 	unsigned int divider;
797 	int prescaler = 0;
798 	unsigned int clk_in = clk_get_rate(host->clk_per);
799 
800 	while (prescaler <= 0x800) {
801 		for (divider = 1; divider <= 0xF; divider++) {
802 			int x;
803 
804 			x = (clk_in / (divider + 1));
805 
806 			if (prescaler)
807 				x /= (prescaler * 2);
808 
809 			if (x <= clk_ios)
810 				break;
811 		}
812 		if (divider < 0x10)
813 			break;
814 
815 		if (prescaler == 0)
816 			prescaler = 1;
817 		else
818 			prescaler <<= 1;
819 	}
820 
821 	mxcmci_writew(host, (prescaler << 4) | divider, MMC_REG_CLK_RATE);
822 
823 	dev_dbg(mmc_dev(host->mmc), "scaler: %d divider: %d in: %d out: %d\n",
824 			prescaler, divider, clk_in, clk_ios);
825 }
826 
827 static int mxcmci_setup_dma(struct mmc_host *mmc)
828 {
829 	struct mxcmci_host *host = mmc_priv(mmc);
830 	struct dma_slave_config *config = &host->dma_slave_config;
831 
832 	config->dst_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
833 	config->src_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
834 	config->dst_addr_width = 4;
835 	config->src_addr_width = 4;
836 	config->dst_maxburst = host->burstlen;
837 	config->src_maxburst = host->burstlen;
838 	config->device_fc = false;
839 
840 	return dmaengine_slave_config(host->dma, config);
841 }
842 
843 static void mxcmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
844 {
845 	struct mxcmci_host *host = mmc_priv(mmc);
846 	int burstlen, ret;
847 
848 	/*
849 	 * use burstlen of 64 (16 words) in 4 bit mode (--> reg value  0)
850 	 * use burstlen of 16 (4 words) in 1 bit mode (--> reg value 16)
851 	 */
852 	if (ios->bus_width == MMC_BUS_WIDTH_4)
853 		burstlen = 16;
854 	else
855 		burstlen = 4;
856 
857 	if (mxcmci_use_dma(host) && burstlen != host->burstlen) {
858 		host->burstlen = burstlen;
859 		ret = mxcmci_setup_dma(mmc);
860 		if (ret) {
861 			dev_err(mmc_dev(host->mmc),
862 				"failed to config DMA channel. Falling back to PIO\n");
863 			dma_release_channel(host->dma);
864 			host->do_dma = 0;
865 			host->dma = NULL;
866 		}
867 	}
868 
869 	if (ios->bus_width == MMC_BUS_WIDTH_4)
870 		host->cmdat |= CMD_DAT_CONT_BUS_WIDTH_4;
871 	else
872 		host->cmdat &= ~CMD_DAT_CONT_BUS_WIDTH_4;
873 
874 	if (host->power_mode != ios->power_mode) {
875 		host->power_mode = ios->power_mode;
876 		mxcmci_set_power(host, ios->vdd);
877 
878 		if (ios->power_mode == MMC_POWER_ON)
879 			host->cmdat |= CMD_DAT_CONT_INIT;
880 	}
881 
882 	if (ios->clock) {
883 		mxcmci_set_clk_rate(host, ios->clock);
884 		mxcmci_writew(host, STR_STP_CLK_START_CLK, MMC_REG_STR_STP_CLK);
885 	} else {
886 		mxcmci_writew(host, STR_STP_CLK_STOP_CLK, MMC_REG_STR_STP_CLK);
887 	}
888 
889 	host->clock = ios->clock;
890 }
891 
892 static irqreturn_t mxcmci_detect_irq(int irq, void *data)
893 {
894 	struct mmc_host *mmc = data;
895 
896 	dev_dbg(mmc_dev(mmc), "%s\n", __func__);
897 
898 	mmc_detect_change(mmc, msecs_to_jiffies(250));
899 	return IRQ_HANDLED;
900 }
901 
902 static int mxcmci_get_ro(struct mmc_host *mmc)
903 {
904 	struct mxcmci_host *host = mmc_priv(mmc);
905 
906 	if (host->pdata && host->pdata->get_ro)
907 		return !!host->pdata->get_ro(mmc_dev(mmc));
908 	/*
909 	 * If board doesn't support read only detection (no mmc_gpio
910 	 * context or gpio is invalid), then let the mmc core decide
911 	 * what to do.
912 	 */
913 	return mmc_gpio_get_ro(mmc);
914 }
915 
916 static void mxcmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
917 {
918 	struct mxcmci_host *host = mmc_priv(mmc);
919 	unsigned long flags;
920 	u32 int_cntr;
921 
922 	spin_lock_irqsave(&host->lock, flags);
923 	host->use_sdio = enable;
924 	int_cntr = mxcmci_readl(host, MMC_REG_INT_CNTR);
925 
926 	if (enable)
927 		int_cntr |= INT_SDIO_IRQ_EN;
928 	else
929 		int_cntr &= ~INT_SDIO_IRQ_EN;
930 
931 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
932 	spin_unlock_irqrestore(&host->lock, flags);
933 }
934 
935 static void mxcmci_init_card(struct mmc_host *host, struct mmc_card *card)
936 {
937 	struct mxcmci_host *mxcmci = mmc_priv(host);
938 
939 	/*
940 	 * MX3 SoCs have a silicon bug which corrupts CRC calculation of
941 	 * multi-block transfers when connected SDIO peripheral doesn't
942 	 * drive the BUSY line as required by the specs.
943 	 * One way to prevent this is to only allow 1-bit transfers.
944 	 */
945 
946 	if (is_imx31_mmc(mxcmci) && card->type == MMC_TYPE_SDIO)
947 		host->caps &= ~MMC_CAP_4_BIT_DATA;
948 	else
949 		host->caps |= MMC_CAP_4_BIT_DATA;
950 }
951 
952 static bool filter(struct dma_chan *chan, void *param)
953 {
954 	struct mxcmci_host *host = param;
955 
956 	if (!imx_dma_is_general_purpose(chan))
957 		return false;
958 
959 	chan->private = &host->dma_data;
960 
961 	return true;
962 }
963 
964 static void mxcmci_watchdog(struct timer_list *t)
965 {
966 	struct mxcmci_host *host = from_timer(host, t, watchdog);
967 	struct mmc_request *req = host->req;
968 	unsigned int stat = mxcmci_readl(host, MMC_REG_STATUS);
969 
970 	if (host->dma_dir == DMA_FROM_DEVICE) {
971 		dmaengine_terminate_all(host->dma);
972 		dev_err(mmc_dev(host->mmc),
973 			"%s: read time out (status = 0x%08x)\n",
974 			__func__, stat);
975 	} else {
976 		dev_err(mmc_dev(host->mmc),
977 			"%s: write time out (status = 0x%08x)\n",
978 			__func__, stat);
979 		mxcmci_softreset(host);
980 	}
981 
982 	/* Mark transfer as erroneus and inform the upper layers */
983 
984 	if (host->data)
985 		host->data->error = -ETIMEDOUT;
986 	host->req = NULL;
987 	host->cmd = NULL;
988 	host->data = NULL;
989 	mmc_request_done(host->mmc, req);
990 }
991 
992 static const struct mmc_host_ops mxcmci_ops = {
993 	.request		= mxcmci_request,
994 	.set_ios		= mxcmci_set_ios,
995 	.get_ro			= mxcmci_get_ro,
996 	.enable_sdio_irq	= mxcmci_enable_sdio_irq,
997 	.init_card		= mxcmci_init_card,
998 };
999 
1000 static int mxcmci_probe(struct platform_device *pdev)
1001 {
1002 	struct mmc_host *mmc;
1003 	struct mxcmci_host *host;
1004 	struct resource *res;
1005 	int ret = 0, irq;
1006 	bool dat3_card_detect = false;
1007 	dma_cap_mask_t mask;
1008 	const struct of_device_id *of_id;
1009 	struct imxmmc_platform_data *pdata = pdev->dev.platform_data;
1010 
1011 	pr_info("i.MX/MPC512x SDHC driver\n");
1012 
1013 	of_id = of_match_device(mxcmci_of_match, &pdev->dev);
1014 
1015 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1016 	irq = platform_get_irq(pdev, 0);
1017 	if (irq < 0) {
1018 		dev_err(&pdev->dev, "failed to get IRQ: %d\n", irq);
1019 		return irq;
1020 	}
1021 
1022 	mmc = mmc_alloc_host(sizeof(*host), &pdev->dev);
1023 	if (!mmc)
1024 		return -ENOMEM;
1025 
1026 	host = mmc_priv(mmc);
1027 
1028 	host->base = devm_ioremap_resource(&pdev->dev, res);
1029 	if (IS_ERR(host->base)) {
1030 		ret = PTR_ERR(host->base);
1031 		goto out_free;
1032 	}
1033 
1034 	host->phys_base = res->start;
1035 
1036 	ret = mmc_of_parse(mmc);
1037 	if (ret)
1038 		goto out_free;
1039 	mmc->ops = &mxcmci_ops;
1040 
1041 	/* For devicetree parsing, the bus width is read from devicetree */
1042 	if (pdata)
1043 		mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
1044 	else
1045 		mmc->caps |= MMC_CAP_SDIO_IRQ;
1046 
1047 	/* MMC core transfer sizes tunable parameters */
1048 	mmc->max_blk_size = 2048;
1049 	mmc->max_blk_count = 65535;
1050 	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
1051 	mmc->max_seg_size = mmc->max_req_size;
1052 
1053 	if (of_id) {
1054 		const struct platform_device_id *id_entry = of_id->data;
1055 		host->devtype = id_entry->driver_data;
1056 	} else {
1057 		host->devtype = pdev->id_entry->driver_data;
1058 	}
1059 
1060 	/* adjust max_segs after devtype detection */
1061 	if (!is_mpc512x_mmc(host))
1062 		mmc->max_segs = 64;
1063 
1064 	host->mmc = mmc;
1065 	host->pdata = pdata;
1066 	spin_lock_init(&host->lock);
1067 
1068 	if (pdata)
1069 		dat3_card_detect = pdata->dat3_card_detect;
1070 	else if (mmc_card_is_removable(mmc)
1071 			&& !of_property_read_bool(pdev->dev.of_node, "cd-gpios"))
1072 		dat3_card_detect = true;
1073 
1074 	ret = mmc_regulator_get_supply(mmc);
1075 	if (ret)
1076 		goto out_free;
1077 
1078 	if (!mmc->ocr_avail) {
1079 		if (pdata && pdata->ocr_avail)
1080 			mmc->ocr_avail = pdata->ocr_avail;
1081 		else
1082 			mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
1083 	}
1084 
1085 	if (dat3_card_detect)
1086 		host->default_irq_mask =
1087 			INT_CARD_INSERTION_EN | INT_CARD_REMOVAL_EN;
1088 	else
1089 		host->default_irq_mask = 0;
1090 
1091 	host->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1092 	if (IS_ERR(host->clk_ipg)) {
1093 		ret = PTR_ERR(host->clk_ipg);
1094 		goto out_free;
1095 	}
1096 
1097 	host->clk_per = devm_clk_get(&pdev->dev, "per");
1098 	if (IS_ERR(host->clk_per)) {
1099 		ret = PTR_ERR(host->clk_per);
1100 		goto out_free;
1101 	}
1102 
1103 	ret = clk_prepare_enable(host->clk_per);
1104 	if (ret)
1105 		goto out_free;
1106 
1107 	ret = clk_prepare_enable(host->clk_ipg);
1108 	if (ret)
1109 		goto out_clk_per_put;
1110 
1111 	mxcmci_softreset(host);
1112 
1113 	host->rev_no = mxcmci_readw(host, MMC_REG_REV_NO);
1114 	if (host->rev_no != 0x400) {
1115 		ret = -ENODEV;
1116 		dev_err(mmc_dev(host->mmc), "wrong rev.no. 0x%08x. aborting.\n",
1117 			host->rev_no);
1118 		goto out_clk_put;
1119 	}
1120 
1121 	mmc->f_min = clk_get_rate(host->clk_per) >> 16;
1122 	mmc->f_max = clk_get_rate(host->clk_per) >> 1;
1123 
1124 	/* recommended in data sheet */
1125 	mxcmci_writew(host, 0x2db4, MMC_REG_READ_TO);
1126 
1127 	mxcmci_writel(host, host->default_irq_mask, MMC_REG_INT_CNTR);
1128 
1129 	if (!host->pdata) {
1130 		host->dma = dma_request_slave_channel(&pdev->dev, "rx-tx");
1131 	} else {
1132 		res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1133 		if (res) {
1134 			host->dmareq = res->start;
1135 			host->dma_data.peripheral_type = IMX_DMATYPE_SDHC;
1136 			host->dma_data.priority = DMA_PRIO_LOW;
1137 			host->dma_data.dma_request = host->dmareq;
1138 			dma_cap_zero(mask);
1139 			dma_cap_set(DMA_SLAVE, mask);
1140 			host->dma = dma_request_channel(mask, filter, host);
1141 		}
1142 	}
1143 	if (host->dma)
1144 		mmc->max_seg_size = dma_get_max_seg_size(
1145 				host->dma->device->dev);
1146 	else
1147 		dev_info(mmc_dev(host->mmc), "dma not available. Using PIO\n");
1148 
1149 	INIT_WORK(&host->datawork, mxcmci_datawork);
1150 
1151 	ret = devm_request_irq(&pdev->dev, irq, mxcmci_irq, 0,
1152 			       dev_name(&pdev->dev), host);
1153 	if (ret)
1154 		goto out_free_dma;
1155 
1156 	platform_set_drvdata(pdev, mmc);
1157 
1158 	if (host->pdata && host->pdata->init) {
1159 		ret = host->pdata->init(&pdev->dev, mxcmci_detect_irq,
1160 				host->mmc);
1161 		if (ret)
1162 			goto out_free_dma;
1163 	}
1164 
1165 	timer_setup(&host->watchdog, mxcmci_watchdog, 0);
1166 
1167 	mmc_add_host(mmc);
1168 
1169 	return 0;
1170 
1171 out_free_dma:
1172 	if (host->dma)
1173 		dma_release_channel(host->dma);
1174 
1175 out_clk_put:
1176 	clk_disable_unprepare(host->clk_ipg);
1177 out_clk_per_put:
1178 	clk_disable_unprepare(host->clk_per);
1179 
1180 out_free:
1181 	mmc_free_host(mmc);
1182 
1183 	return ret;
1184 }
1185 
1186 static int mxcmci_remove(struct platform_device *pdev)
1187 {
1188 	struct mmc_host *mmc = platform_get_drvdata(pdev);
1189 	struct mxcmci_host *host = mmc_priv(mmc);
1190 
1191 	mmc_remove_host(mmc);
1192 
1193 	if (host->pdata && host->pdata->exit)
1194 		host->pdata->exit(&pdev->dev, mmc);
1195 
1196 	if (host->dma)
1197 		dma_release_channel(host->dma);
1198 
1199 	clk_disable_unprepare(host->clk_per);
1200 	clk_disable_unprepare(host->clk_ipg);
1201 
1202 	mmc_free_host(mmc);
1203 
1204 	return 0;
1205 }
1206 
1207 #ifdef CONFIG_PM_SLEEP
1208 static int mxcmci_suspend(struct device *dev)
1209 {
1210 	struct mmc_host *mmc = dev_get_drvdata(dev);
1211 	struct mxcmci_host *host = mmc_priv(mmc);
1212 
1213 	clk_disable_unprepare(host->clk_per);
1214 	clk_disable_unprepare(host->clk_ipg);
1215 	return 0;
1216 }
1217 
1218 static int mxcmci_resume(struct device *dev)
1219 {
1220 	struct mmc_host *mmc = dev_get_drvdata(dev);
1221 	struct mxcmci_host *host = mmc_priv(mmc);
1222 	int ret;
1223 
1224 	ret = clk_prepare_enable(host->clk_per);
1225 	if (ret)
1226 		return ret;
1227 
1228 	ret = clk_prepare_enable(host->clk_ipg);
1229 	if (ret)
1230 		clk_disable_unprepare(host->clk_per);
1231 
1232 	return ret;
1233 }
1234 #endif
1235 
1236 static SIMPLE_DEV_PM_OPS(mxcmci_pm_ops, mxcmci_suspend, mxcmci_resume);
1237 
1238 static struct platform_driver mxcmci_driver = {
1239 	.probe		= mxcmci_probe,
1240 	.remove		= mxcmci_remove,
1241 	.id_table	= mxcmci_devtype,
1242 	.driver		= {
1243 		.name		= DRIVER_NAME,
1244 		.pm	= &mxcmci_pm_ops,
1245 		.of_match_table	= mxcmci_of_match,
1246 	}
1247 };
1248 
1249 module_platform_driver(mxcmci_driver);
1250 
1251 MODULE_DESCRIPTION("i.MX Multimedia Card Interface Driver");
1252 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1253 MODULE_LICENSE("GPL");
1254 MODULE_ALIAS("platform:mxc-mmc");
1255