xref: /linux/drivers/mmc/host/mxcmmc.c (revision 5c35a02c545a7bbe77f3a1ae337d9e29beed079b)
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/gpio.h>
35 #include <linux/regulator/consumer.h>
36 #include <linux/dmaengine.h>
37 #include <linux/types.h>
38 #include <linux/of.h>
39 #include <linux/of_device.h>
40 #include <linux/of_dma.h>
41 #include <linux/of_gpio.h>
42 #include <linux/mmc/slot-gpio.h>
43 
44 #include <asm/dma.h>
45 #include <asm/irq.h>
46 #include <linux/platform_data/mmc-mxcmmc.h>
47 
48 #include <linux/platform_data/dma-imx.h>
49 
50 #define DRIVER_NAME "mxc-mmc"
51 #define MXCMCI_TIMEOUT_MS 10000
52 
53 #define MMC_REG_STR_STP_CLK		0x00
54 #define MMC_REG_STATUS			0x04
55 #define MMC_REG_CLK_RATE		0x08
56 #define MMC_REG_CMD_DAT_CONT		0x0C
57 #define MMC_REG_RES_TO			0x10
58 #define MMC_REG_READ_TO			0x14
59 #define MMC_REG_BLK_LEN			0x18
60 #define MMC_REG_NOB			0x1C
61 #define MMC_REG_REV_NO			0x20
62 #define MMC_REG_INT_CNTR		0x24
63 #define MMC_REG_CMD			0x28
64 #define MMC_REG_ARG			0x2C
65 #define MMC_REG_RES_FIFO		0x34
66 #define MMC_REG_BUFFER_ACCESS		0x38
67 
68 #define STR_STP_CLK_RESET               (1 << 3)
69 #define STR_STP_CLK_START_CLK           (1 << 1)
70 #define STR_STP_CLK_STOP_CLK            (1 << 0)
71 
72 #define STATUS_CARD_INSERTION		(1 << 31)
73 #define STATUS_CARD_REMOVAL		(1 << 30)
74 #define STATUS_YBUF_EMPTY		(1 << 29)
75 #define STATUS_XBUF_EMPTY		(1 << 28)
76 #define STATUS_YBUF_FULL		(1 << 27)
77 #define STATUS_XBUF_FULL		(1 << 26)
78 #define STATUS_BUF_UND_RUN		(1 << 25)
79 #define STATUS_BUF_OVFL			(1 << 24)
80 #define STATUS_SDIO_INT_ACTIVE		(1 << 14)
81 #define STATUS_END_CMD_RESP		(1 << 13)
82 #define STATUS_WRITE_OP_DONE		(1 << 12)
83 #define STATUS_DATA_TRANS_DONE		(1 << 11)
84 #define STATUS_READ_OP_DONE		(1 << 11)
85 #define STATUS_WR_CRC_ERROR_CODE_MASK	(3 << 10)
86 #define STATUS_CARD_BUS_CLK_RUN		(1 << 8)
87 #define STATUS_BUF_READ_RDY		(1 << 7)
88 #define STATUS_BUF_WRITE_RDY		(1 << 6)
89 #define STATUS_RESP_CRC_ERR		(1 << 5)
90 #define STATUS_CRC_READ_ERR		(1 << 3)
91 #define STATUS_CRC_WRITE_ERR		(1 << 2)
92 #define STATUS_TIME_OUT_RESP		(1 << 1)
93 #define STATUS_TIME_OUT_READ		(1 << 0)
94 #define STATUS_ERR_MASK			0x2f
95 
96 #define CMD_DAT_CONT_CMD_RESP_LONG_OFF	(1 << 12)
97 #define CMD_DAT_CONT_STOP_READWAIT	(1 << 11)
98 #define CMD_DAT_CONT_START_READWAIT	(1 << 10)
99 #define CMD_DAT_CONT_BUS_WIDTH_4	(2 << 8)
100 #define CMD_DAT_CONT_INIT		(1 << 7)
101 #define CMD_DAT_CONT_WRITE		(1 << 4)
102 #define CMD_DAT_CONT_DATA_ENABLE	(1 << 3)
103 #define CMD_DAT_CONT_RESPONSE_48BIT_CRC	(1 << 0)
104 #define CMD_DAT_CONT_RESPONSE_136BIT	(2 << 0)
105 #define CMD_DAT_CONT_RESPONSE_48BIT	(3 << 0)
106 
107 #define INT_SDIO_INT_WKP_EN		(1 << 18)
108 #define INT_CARD_INSERTION_WKP_EN	(1 << 17)
109 #define INT_CARD_REMOVAL_WKP_EN		(1 << 16)
110 #define INT_CARD_INSERTION_EN		(1 << 15)
111 #define INT_CARD_REMOVAL_EN		(1 << 14)
112 #define INT_SDIO_IRQ_EN			(1 << 13)
113 #define INT_DAT0_EN			(1 << 12)
114 #define INT_BUF_READ_EN			(1 << 4)
115 #define INT_BUF_WRITE_EN		(1 << 3)
116 #define INT_END_CMD_RES_EN		(1 << 2)
117 #define INT_WRITE_OP_DONE_EN		(1 << 1)
118 #define INT_READ_OP_EN			(1 << 0)
119 
120 enum mxcmci_type {
121 	IMX21_MMC,
122 	IMX31_MMC,
123 	MPC512X_MMC,
124 };
125 
126 struct mxcmci_host {
127 	struct mmc_host		*mmc;
128 	void __iomem		*base;
129 	dma_addr_t		phys_base;
130 	int			detect_irq;
131 	struct dma_chan		*dma;
132 	struct dma_async_tx_descriptor *desc;
133 	int			do_dma;
134 	int			default_irq_mask;
135 	int			use_sdio;
136 	unsigned int		power_mode;
137 	struct imxmmc_platform_data *pdata;
138 
139 	struct mmc_request	*req;
140 	struct mmc_command	*cmd;
141 	struct mmc_data		*data;
142 
143 	unsigned int		datasize;
144 	unsigned int		dma_dir;
145 
146 	u16			rev_no;
147 	unsigned int		cmdat;
148 
149 	struct clk		*clk_ipg;
150 	struct clk		*clk_per;
151 
152 	int			clock;
153 
154 	struct work_struct	datawork;
155 	spinlock_t		lock;
156 
157 	int			burstlen;
158 	int			dmareq;
159 	struct dma_slave_config dma_slave_config;
160 	struct imx_dma_data	dma_data;
161 
162 	struct timer_list	watchdog;
163 	enum mxcmci_type	devtype;
164 };
165 
166 static const struct platform_device_id mxcmci_devtype[] = {
167 	{
168 		.name = "imx21-mmc",
169 		.driver_data = IMX21_MMC,
170 	}, {
171 		.name = "imx31-mmc",
172 		.driver_data = IMX31_MMC,
173 	}, {
174 		.name = "mpc512x-sdhc",
175 		.driver_data = MPC512X_MMC,
176 	}, {
177 		/* sentinel */
178 	}
179 };
180 MODULE_DEVICE_TABLE(platform, mxcmci_devtype);
181 
182 static const struct of_device_id mxcmci_of_match[] = {
183 	{
184 		.compatible = "fsl,imx21-mmc",
185 		.data = &mxcmci_devtype[IMX21_MMC],
186 	}, {
187 		.compatible = "fsl,imx31-mmc",
188 		.data = &mxcmci_devtype[IMX31_MMC],
189 	}, {
190 		.compatible = "fsl,mpc5121-sdhc",
191 		.data = &mxcmci_devtype[MPC512X_MMC],
192 	}, {
193 		/* sentinel */
194 	}
195 };
196 MODULE_DEVICE_TABLE(of, mxcmci_of_match);
197 
198 static inline int is_imx31_mmc(struct mxcmci_host *host)
199 {
200 	return host->devtype == IMX31_MMC;
201 }
202 
203 static inline int is_mpc512x_mmc(struct mxcmci_host *host)
204 {
205 	return host->devtype == MPC512X_MMC;
206 }
207 
208 static inline u32 mxcmci_readl(struct mxcmci_host *host, int reg)
209 {
210 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
211 		return ioread32be(host->base + reg);
212 	else
213 		return readl(host->base + reg);
214 }
215 
216 static inline void mxcmci_writel(struct mxcmci_host *host, u32 val, int reg)
217 {
218 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
219 		iowrite32be(val, host->base + reg);
220 	else
221 		writel(val, host->base + reg);
222 }
223 
224 static inline u16 mxcmci_readw(struct mxcmci_host *host, int reg)
225 {
226 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
227 		return ioread32be(host->base + reg);
228 	else
229 		return readw(host->base + reg);
230 }
231 
232 static inline void mxcmci_writew(struct mxcmci_host *host, u16 val, int reg)
233 {
234 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
235 		iowrite32be(val, host->base + reg);
236 	else
237 		writew(val, host->base + reg);
238 }
239 
240 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios);
241 
242 static void mxcmci_set_power(struct mxcmci_host *host, unsigned int vdd)
243 {
244 	if (!IS_ERR(host->mmc->supply.vmmc)) {
245 		if (host->power_mode == MMC_POWER_UP)
246 			mmc_regulator_set_ocr(host->mmc,
247 					      host->mmc->supply.vmmc, vdd);
248 		else if (host->power_mode == MMC_POWER_OFF)
249 			mmc_regulator_set_ocr(host->mmc,
250 					      host->mmc->supply.vmmc, 0);
251 	}
252 
253 	if (host->pdata && host->pdata->setpower)
254 		host->pdata->setpower(mmc_dev(host->mmc), vdd);
255 }
256 
257 static inline int mxcmci_use_dma(struct mxcmci_host *host)
258 {
259 	return host->do_dma;
260 }
261 
262 static void mxcmci_softreset(struct mxcmci_host *host)
263 {
264 	int i;
265 
266 	dev_dbg(mmc_dev(host->mmc), "mxcmci_softreset\n");
267 
268 	/* reset sequence */
269 	mxcmci_writew(host, STR_STP_CLK_RESET, MMC_REG_STR_STP_CLK);
270 	mxcmci_writew(host, STR_STP_CLK_RESET | STR_STP_CLK_START_CLK,
271 			MMC_REG_STR_STP_CLK);
272 
273 	for (i = 0; i < 8; i++)
274 		mxcmci_writew(host, STR_STP_CLK_START_CLK, MMC_REG_STR_STP_CLK);
275 
276 	mxcmci_writew(host, 0xff, MMC_REG_RES_TO);
277 }
278 
279 #if IS_ENABLED(CONFIG_PPC_MPC512x)
280 static inline void buffer_swap32(u32 *buf, int len)
281 {
282 	int i;
283 
284 	for (i = 0; i < ((len + 3) / 4); i++) {
285 		*buf = swab32(*buf);
286 		buf++;
287 	}
288 }
289 
290 static void mxcmci_swap_buffers(struct mmc_data *data)
291 {
292 	struct scatterlist *sg;
293 	int i;
294 
295 	for_each_sg(data->sg, sg, data->sg_len, i) {
296 		void *buf = kmap_atomic(sg_page(sg) + sg->offset;
297 		buffer_swap32(buf, sg->length);
298 		kunmap_atomic(buf);
299 }
300 #else
301 static inline void mxcmci_swap_buffers(struct mmc_data *data) {}
302 #endif
303 
304 static int mxcmci_setup_data(struct mxcmci_host *host, struct mmc_data *data)
305 {
306 	unsigned int nob = data->blocks;
307 	unsigned int blksz = data->blksz;
308 	unsigned int datasize = nob * blksz;
309 	struct scatterlist *sg;
310 	enum dma_transfer_direction slave_dirn;
311 	int i, nents;
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 
377 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
378 
379 	mxcmci_data_done(host, stat);
380 }
381 
382 static int mxcmci_start_cmd(struct mxcmci_host *host, struct mmc_command *cmd,
383 		unsigned int cmdat)
384 {
385 	u32 int_cntr = host->default_irq_mask;
386 	unsigned long flags;
387 
388 	WARN_ON(host->cmd != NULL);
389 	host->cmd = cmd;
390 
391 	switch (mmc_resp_type(cmd)) {
392 	case MMC_RSP_R1: /* short CRC, OPCODE */
393 	case MMC_RSP_R1B:/* short CRC, OPCODE, BUSY */
394 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT_CRC;
395 		break;
396 	case MMC_RSP_R2: /* long 136 bit + CRC */
397 		cmdat |= CMD_DAT_CONT_RESPONSE_136BIT;
398 		break;
399 	case MMC_RSP_R3: /* short */
400 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT;
401 		break;
402 	case MMC_RSP_NONE:
403 		break;
404 	default:
405 		dev_err(mmc_dev(host->mmc), "unhandled response type 0x%x\n",
406 				mmc_resp_type(cmd));
407 		cmd->error = -EINVAL;
408 		return -EINVAL;
409 	}
410 
411 	int_cntr = INT_END_CMD_RES_EN;
412 
413 	if (mxcmci_use_dma(host)) {
414 		if (host->dma_dir == DMA_FROM_DEVICE) {
415 			host->desc->callback = mxcmci_dma_callback;
416 			host->desc->callback_param = host;
417 		} else {
418 			int_cntr |= INT_WRITE_OP_DONE_EN;
419 		}
420 	}
421 
422 	spin_lock_irqsave(&host->lock, flags);
423 	if (host->use_sdio)
424 		int_cntr |= INT_SDIO_IRQ_EN;
425 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
426 	spin_unlock_irqrestore(&host->lock, flags);
427 
428 	mxcmci_writew(host, cmd->opcode, MMC_REG_CMD);
429 	mxcmci_writel(host, cmd->arg, MMC_REG_ARG);
430 	mxcmci_writew(host, cmdat, MMC_REG_CMD_DAT_CONT);
431 
432 	return 0;
433 }
434 
435 static void mxcmci_finish_request(struct mxcmci_host *host,
436 		struct mmc_request *req)
437 {
438 	u32 int_cntr = host->default_irq_mask;
439 	unsigned long flags;
440 
441 	spin_lock_irqsave(&host->lock, flags);
442 	if (host->use_sdio)
443 		int_cntr |= INT_SDIO_IRQ_EN;
444 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
445 	spin_unlock_irqrestore(&host->lock, flags);
446 
447 	host->req = NULL;
448 	host->cmd = NULL;
449 	host->data = NULL;
450 
451 	mmc_request_done(host->mmc, req);
452 }
453 
454 static int mxcmci_finish_data(struct mxcmci_host *host, unsigned int stat)
455 {
456 	struct mmc_data *data = host->data;
457 	int data_error;
458 
459 	if (mxcmci_use_dma(host)) {
460 		dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
461 				host->dma_dir);
462 		mxcmci_swap_buffers(data);
463 	}
464 
465 	if (stat & STATUS_ERR_MASK) {
466 		dev_dbg(mmc_dev(host->mmc), "request failed. status: 0x%08x\n",
467 				stat);
468 		if (stat & STATUS_CRC_READ_ERR) {
469 			dev_err(mmc_dev(host->mmc), "%s: -EILSEQ\n", __func__);
470 			data->error = -EILSEQ;
471 		} else if (stat & STATUS_CRC_WRITE_ERR) {
472 			u32 err_code = (stat >> 9) & 0x3;
473 			if (err_code == 2) { /* No CRC response */
474 				dev_err(mmc_dev(host->mmc),
475 					"%s: No CRC -ETIMEDOUT\n", __func__);
476 				data->error = -ETIMEDOUT;
477 			} else {
478 				dev_err(mmc_dev(host->mmc),
479 					"%s: -EILSEQ\n", __func__);
480 				data->error = -EILSEQ;
481 			}
482 		} else if (stat & STATUS_TIME_OUT_READ) {
483 			dev_err(mmc_dev(host->mmc),
484 				"%s: read -ETIMEDOUT\n", __func__);
485 			data->error = -ETIMEDOUT;
486 		} else {
487 			dev_err(mmc_dev(host->mmc), "%s: -EIO\n", __func__);
488 			data->error = -EIO;
489 		}
490 	} else {
491 		data->bytes_xfered = host->datasize;
492 	}
493 
494 	data_error = data->error;
495 
496 	host->data = NULL;
497 
498 	return data_error;
499 }
500 
501 static void mxcmci_read_response(struct mxcmci_host *host, unsigned int stat)
502 {
503 	struct mmc_command *cmd = host->cmd;
504 	int i;
505 	u32 a, b, c;
506 
507 	if (!cmd)
508 		return;
509 
510 	if (stat & STATUS_TIME_OUT_RESP) {
511 		dev_dbg(mmc_dev(host->mmc), "CMD TIMEOUT\n");
512 		cmd->error = -ETIMEDOUT;
513 	} else if (stat & STATUS_RESP_CRC_ERR && cmd->flags & MMC_RSP_CRC) {
514 		dev_dbg(mmc_dev(host->mmc), "cmd crc error\n");
515 		cmd->error = -EILSEQ;
516 	}
517 
518 	if (cmd->flags & MMC_RSP_PRESENT) {
519 		if (cmd->flags & MMC_RSP_136) {
520 			for (i = 0; i < 4; i++) {
521 				a = mxcmci_readw(host, MMC_REG_RES_FIFO);
522 				b = mxcmci_readw(host, MMC_REG_RES_FIFO);
523 				cmd->resp[i] = a << 16 | b;
524 			}
525 		} else {
526 			a = mxcmci_readw(host, MMC_REG_RES_FIFO);
527 			b = mxcmci_readw(host, MMC_REG_RES_FIFO);
528 			c = mxcmci_readw(host, MMC_REG_RES_FIFO);
529 			cmd->resp[0] = a << 24 | b << 8 | c >> 8;
530 		}
531 	}
532 }
533 
534 static int mxcmci_poll_status(struct mxcmci_host *host, u32 mask)
535 {
536 	u32 stat;
537 	unsigned long timeout = jiffies + HZ;
538 
539 	do {
540 		stat = mxcmci_readl(host, MMC_REG_STATUS);
541 		if (stat & STATUS_ERR_MASK)
542 			return stat;
543 		if (time_after(jiffies, timeout)) {
544 			mxcmci_softreset(host);
545 			mxcmci_set_clk_rate(host, host->clock);
546 			return STATUS_TIME_OUT_READ;
547 		}
548 		if (stat & mask)
549 			return 0;
550 		cpu_relax();
551 	} while (1);
552 }
553 
554 static int mxcmci_pull(struct mxcmci_host *host, void *_buf, int bytes)
555 {
556 	unsigned int stat;
557 	u32 *buf = _buf;
558 
559 	while (bytes > 3) {
560 		stat = mxcmci_poll_status(host,
561 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
562 		if (stat)
563 			return stat;
564 		*buf++ = cpu_to_le32(mxcmci_readl(host, MMC_REG_BUFFER_ACCESS));
565 		bytes -= 4;
566 	}
567 
568 	if (bytes) {
569 		u8 *b = (u8 *)buf;
570 		u32 tmp;
571 
572 		stat = mxcmci_poll_status(host,
573 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
574 		if (stat)
575 			return stat;
576 		tmp = cpu_to_le32(mxcmci_readl(host, MMC_REG_BUFFER_ACCESS));
577 		memcpy(b, &tmp, bytes);
578 	}
579 
580 	return 0;
581 }
582 
583 static int mxcmci_push(struct mxcmci_host *host, void *_buf, int bytes)
584 {
585 	unsigned int stat;
586 	u32 *buf = _buf;
587 
588 	while (bytes > 3) {
589 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
590 		if (stat)
591 			return stat;
592 		mxcmci_writel(host, cpu_to_le32(*buf++), MMC_REG_BUFFER_ACCESS);
593 		bytes -= 4;
594 	}
595 
596 	if (bytes) {
597 		u8 *b = (u8 *)buf;
598 		u32 tmp;
599 
600 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
601 		if (stat)
602 			return stat;
603 
604 		memcpy(&tmp, b, bytes);
605 		mxcmci_writel(host, cpu_to_le32(tmp), MMC_REG_BUFFER_ACCESS);
606 	}
607 
608 	return mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
609 }
610 
611 static int mxcmci_transfer_data(struct mxcmci_host *host)
612 {
613 	struct mmc_data *data = host->req->data;
614 	struct scatterlist *sg;
615 	void *buf;
616 	int stat, i;
617 
618 	host->data = data;
619 	host->datasize = 0;
620 
621 	if (data->flags & MMC_DATA_READ) {
622 		for_each_sg(data->sg, sg, data->sg_len, i) {
623 			buf = kmap_atomic(sg_page(sg) + sg->offset);
624 			stat = mxcmci_pull(host, buf, sg->length);
625 			kunmap(buf);
626 			if (stat)
627 				return stat;
628 			host->datasize += sg->length;
629 		}
630 	} else {
631 		for_each_sg(data->sg, sg, data->sg_len, i) {
632 			buf = kmap_atomic(sg_page(sg) + sg->offset);
633 			stat = mxcmci_push(host, buf, sg->length);
634 			kunmap(buf);
635 			if (stat)
636 				return stat;
637 			host->datasize += sg->length;
638 		}
639 		stat = mxcmci_poll_status(host, STATUS_WRITE_OP_DONE);
640 		if (stat)
641 			return stat;
642 	}
643 	return 0;
644 }
645 
646 static void mxcmci_datawork(struct work_struct *work)
647 {
648 	struct mxcmci_host *host = container_of(work, struct mxcmci_host,
649 						  datawork);
650 	int datastat = mxcmci_transfer_data(host);
651 
652 	mxcmci_writel(host, STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE,
653 		MMC_REG_STATUS);
654 	mxcmci_finish_data(host, datastat);
655 
656 	if (host->req->stop) {
657 		if (mxcmci_start_cmd(host, host->req->stop, 0)) {
658 			mxcmci_finish_request(host, host->req);
659 			return;
660 		}
661 	} else {
662 		mxcmci_finish_request(host, host->req);
663 	}
664 }
665 
666 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat)
667 {
668 	struct mmc_request *req;
669 	int data_error;
670 	unsigned long flags;
671 
672 	spin_lock_irqsave(&host->lock, flags);
673 
674 	if (!host->data) {
675 		spin_unlock_irqrestore(&host->lock, flags);
676 		return;
677 	}
678 
679 	if (!host->req) {
680 		spin_unlock_irqrestore(&host->lock, flags);
681 		return;
682 	}
683 
684 	req = host->req;
685 	if (!req->stop)
686 		host->req = NULL; /* we will handle finish req below */
687 
688 	data_error = mxcmci_finish_data(host, stat);
689 
690 	spin_unlock_irqrestore(&host->lock, flags);
691 
692 	if (data_error)
693 		return;
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) && (stat & (STATUS_WRITE_OP_DONE)))
747 		mxcmci_writel(host, STATUS_WRITE_OP_DONE, MMC_REG_STATUS);
748 
749 	if (sdio_irq) {
750 		mxcmci_writel(host, STATUS_SDIO_INT_ACTIVE, MMC_REG_STATUS);
751 		mmc_signal_sdio_irq(host->mmc);
752 	}
753 
754 	if (stat & STATUS_END_CMD_RESP)
755 		mxcmci_cmd_done(host, stat);
756 
757 	if (mxcmci_use_dma(host) && (stat & STATUS_WRITE_OP_DONE)) {
758 		del_timer(&host->watchdog);
759 		mxcmci_data_done(host, stat);
760 	}
761 
762 	if (host->default_irq_mask &&
763 		  (stat & (STATUS_CARD_INSERTION | STATUS_CARD_REMOVAL)))
764 		mmc_detect_change(host->mmc, msecs_to_jiffies(200));
765 
766 	return IRQ_HANDLED;
767 }
768 
769 static void mxcmci_request(struct mmc_host *mmc, struct mmc_request *req)
770 {
771 	struct mxcmci_host *host = mmc_priv(mmc);
772 	unsigned int cmdat = host->cmdat;
773 	int error;
774 
775 	WARN_ON(host->req != NULL);
776 
777 	host->req = req;
778 	host->cmdat &= ~CMD_DAT_CONT_INIT;
779 
780 	if (host->dma)
781 		host->do_dma = 1;
782 
783 	if (req->data) {
784 		error = mxcmci_setup_data(host, req->data);
785 		if (error) {
786 			req->cmd->error = error;
787 			goto out;
788 		}
789 
790 
791 		cmdat |= CMD_DAT_CONT_DATA_ENABLE;
792 
793 		if (req->data->flags & MMC_DATA_WRITE)
794 			cmdat |= CMD_DAT_CONT_WRITE;
795 	}
796 
797 	error = mxcmci_start_cmd(host, req->cmd, cmdat);
798 
799 out:
800 	if (error)
801 		mxcmci_finish_request(host, req);
802 }
803 
804 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios)
805 {
806 	unsigned int divider;
807 	int prescaler = 0;
808 	unsigned int clk_in = clk_get_rate(host->clk_per);
809 
810 	while (prescaler <= 0x800) {
811 		for (divider = 1; divider <= 0xF; divider++) {
812 			int x;
813 
814 			x = (clk_in / (divider + 1));
815 
816 			if (prescaler)
817 				x /= (prescaler * 2);
818 
819 			if (x <= clk_ios)
820 				break;
821 		}
822 		if (divider < 0x10)
823 			break;
824 
825 		if (prescaler == 0)
826 			prescaler = 1;
827 		else
828 			prescaler <<= 1;
829 	}
830 
831 	mxcmci_writew(host, (prescaler << 4) | divider, MMC_REG_CLK_RATE);
832 
833 	dev_dbg(mmc_dev(host->mmc), "scaler: %d divider: %d in: %d out: %d\n",
834 			prescaler, divider, clk_in, clk_ios);
835 }
836 
837 static int mxcmci_setup_dma(struct mmc_host *mmc)
838 {
839 	struct mxcmci_host *host = mmc_priv(mmc);
840 	struct dma_slave_config *config = &host->dma_slave_config;
841 
842 	config->dst_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
843 	config->src_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
844 	config->dst_addr_width = 4;
845 	config->src_addr_width = 4;
846 	config->dst_maxburst = host->burstlen;
847 	config->src_maxburst = host->burstlen;
848 	config->device_fc = false;
849 
850 	return dmaengine_slave_config(host->dma, config);
851 }
852 
853 static void mxcmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
854 {
855 	struct mxcmci_host *host = mmc_priv(mmc);
856 	int burstlen, ret;
857 
858 	/*
859 	 * use burstlen of 64 (16 words) in 4 bit mode (--> reg value  0)
860 	 * use burstlen of 16 (4 words) in 1 bit mode (--> reg value 16)
861 	 */
862 	if (ios->bus_width == MMC_BUS_WIDTH_4)
863 		burstlen = 16;
864 	else
865 		burstlen = 4;
866 
867 	if (mxcmci_use_dma(host) && burstlen != host->burstlen) {
868 		host->burstlen = burstlen;
869 		ret = mxcmci_setup_dma(mmc);
870 		if (ret) {
871 			dev_err(mmc_dev(host->mmc),
872 				"failed to config DMA channel. Falling back to PIO\n");
873 			dma_release_channel(host->dma);
874 			host->do_dma = 0;
875 			host->dma = NULL;
876 		}
877 	}
878 
879 	if (ios->bus_width == MMC_BUS_WIDTH_4)
880 		host->cmdat |= CMD_DAT_CONT_BUS_WIDTH_4;
881 	else
882 		host->cmdat &= ~CMD_DAT_CONT_BUS_WIDTH_4;
883 
884 	if (host->power_mode != ios->power_mode) {
885 		host->power_mode = ios->power_mode;
886 		mxcmci_set_power(host, ios->vdd);
887 
888 		if (ios->power_mode == MMC_POWER_ON)
889 			host->cmdat |= CMD_DAT_CONT_INIT;
890 	}
891 
892 	if (ios->clock) {
893 		mxcmci_set_clk_rate(host, ios->clock);
894 		mxcmci_writew(host, STR_STP_CLK_START_CLK, MMC_REG_STR_STP_CLK);
895 	} else {
896 		mxcmci_writew(host, STR_STP_CLK_STOP_CLK, MMC_REG_STR_STP_CLK);
897 	}
898 
899 	host->clock = ios->clock;
900 }
901 
902 static irqreturn_t mxcmci_detect_irq(int irq, void *data)
903 {
904 	struct mmc_host *mmc = data;
905 
906 	dev_dbg(mmc_dev(mmc), "%s\n", __func__);
907 
908 	mmc_detect_change(mmc, msecs_to_jiffies(250));
909 	return IRQ_HANDLED;
910 }
911 
912 static int mxcmci_get_ro(struct mmc_host *mmc)
913 {
914 	struct mxcmci_host *host = mmc_priv(mmc);
915 
916 	if (host->pdata && host->pdata->get_ro)
917 		return !!host->pdata->get_ro(mmc_dev(mmc));
918 	/*
919 	 * If board doesn't support read only detection (no mmc_gpio
920 	 * context or gpio is invalid), then let the mmc core decide
921 	 * what to do.
922 	 */
923 	return mmc_gpio_get_ro(mmc);
924 }
925 
926 static void mxcmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
927 {
928 	struct mxcmci_host *host = mmc_priv(mmc);
929 	unsigned long flags;
930 	u32 int_cntr;
931 
932 	spin_lock_irqsave(&host->lock, flags);
933 	host->use_sdio = enable;
934 	int_cntr = mxcmci_readl(host, MMC_REG_INT_CNTR);
935 
936 	if (enable)
937 		int_cntr |= INT_SDIO_IRQ_EN;
938 	else
939 		int_cntr &= ~INT_SDIO_IRQ_EN;
940 
941 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
942 	spin_unlock_irqrestore(&host->lock, flags);
943 }
944 
945 static void mxcmci_init_card(struct mmc_host *host, struct mmc_card *card)
946 {
947 	struct mxcmci_host *mxcmci = mmc_priv(host);
948 
949 	/*
950 	 * MX3 SoCs have a silicon bug which corrupts CRC calculation of
951 	 * multi-block transfers when connected SDIO peripheral doesn't
952 	 * drive the BUSY line as required by the specs.
953 	 * One way to prevent this is to only allow 1-bit transfers.
954 	 */
955 
956 	if (is_imx31_mmc(mxcmci) && card->type == MMC_TYPE_SDIO)
957 		host->caps &= ~MMC_CAP_4_BIT_DATA;
958 	else
959 		host->caps |= MMC_CAP_4_BIT_DATA;
960 }
961 
962 static bool filter(struct dma_chan *chan, void *param)
963 {
964 	struct mxcmci_host *host = param;
965 
966 	if (!imx_dma_is_general_purpose(chan))
967 		return false;
968 
969 	chan->private = &host->dma_data;
970 
971 	return true;
972 }
973 
974 static void mxcmci_watchdog(struct timer_list *t)
975 {
976 	struct mxcmci_host *host = from_timer(host, t, watchdog);
977 	struct mmc_request *req = host->req;
978 	unsigned int stat = mxcmci_readl(host, MMC_REG_STATUS);
979 
980 	if (host->dma_dir == DMA_FROM_DEVICE) {
981 		dmaengine_terminate_all(host->dma);
982 		dev_err(mmc_dev(host->mmc),
983 			"%s: read time out (status = 0x%08x)\n",
984 			__func__, stat);
985 	} else {
986 		dev_err(mmc_dev(host->mmc),
987 			"%s: write time out (status = 0x%08x)\n",
988 			__func__, stat);
989 		mxcmci_softreset(host);
990 	}
991 
992 	/* Mark transfer as erroneus and inform the upper layers */
993 
994 	if (host->data)
995 		host->data->error = -ETIMEDOUT;
996 	host->req = NULL;
997 	host->cmd = NULL;
998 	host->data = NULL;
999 	mmc_request_done(host->mmc, req);
1000 }
1001 
1002 static const struct mmc_host_ops mxcmci_ops = {
1003 	.request		= mxcmci_request,
1004 	.set_ios		= mxcmci_set_ios,
1005 	.get_ro			= mxcmci_get_ro,
1006 	.enable_sdio_irq	= mxcmci_enable_sdio_irq,
1007 	.init_card		= mxcmci_init_card,
1008 };
1009 
1010 static int mxcmci_probe(struct platform_device *pdev)
1011 {
1012 	struct mmc_host *mmc;
1013 	struct mxcmci_host *host;
1014 	struct resource *res;
1015 	int ret = 0, irq;
1016 	bool dat3_card_detect = false;
1017 	dma_cap_mask_t mask;
1018 	const struct of_device_id *of_id;
1019 	struct imxmmc_platform_data *pdata = pdev->dev.platform_data;
1020 
1021 	pr_info("i.MX/MPC512x SDHC driver\n");
1022 
1023 	of_id = of_match_device(mxcmci_of_match, &pdev->dev);
1024 
1025 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1026 	irq = platform_get_irq(pdev, 0);
1027 	if (irq < 0) {
1028 		dev_err(&pdev->dev, "failed to get IRQ: %d\n", irq);
1029 		return irq;
1030 	}
1031 
1032 	mmc = mmc_alloc_host(sizeof(*host), &pdev->dev);
1033 	if (!mmc)
1034 		return -ENOMEM;
1035 
1036 	host = mmc_priv(mmc);
1037 
1038 	host->base = devm_ioremap_resource(&pdev->dev, res);
1039 	if (IS_ERR(host->base)) {
1040 		ret = PTR_ERR(host->base);
1041 		goto out_free;
1042 	}
1043 
1044 	host->phys_base = res->start;
1045 
1046 	ret = mmc_of_parse(mmc);
1047 	if (ret)
1048 		goto out_free;
1049 	mmc->ops = &mxcmci_ops;
1050 
1051 	/* For devicetree parsing, the bus width is read from devicetree */
1052 	if (pdata)
1053 		mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
1054 	else
1055 		mmc->caps |= MMC_CAP_SDIO_IRQ;
1056 
1057 	/* MMC core transfer sizes tunable parameters */
1058 	mmc->max_blk_size = 2048;
1059 	mmc->max_blk_count = 65535;
1060 	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
1061 	mmc->max_seg_size = mmc->max_req_size;
1062 
1063 	if (of_id) {
1064 		const struct platform_device_id *id_entry = of_id->data;
1065 		host->devtype = id_entry->driver_data;
1066 	} else {
1067 		host->devtype = pdev->id_entry->driver_data;
1068 	}
1069 
1070 	/* adjust max_segs after devtype detection */
1071 	if (!is_mpc512x_mmc(host))
1072 		mmc->max_segs = 64;
1073 
1074 	host->mmc = mmc;
1075 	host->pdata = pdata;
1076 	spin_lock_init(&host->lock);
1077 
1078 	if (pdata)
1079 		dat3_card_detect = pdata->dat3_card_detect;
1080 	else if (mmc_card_is_removable(mmc)
1081 			&& !of_property_read_bool(pdev->dev.of_node, "cd-gpios"))
1082 		dat3_card_detect = true;
1083 
1084 	ret = mmc_regulator_get_supply(mmc);
1085 	if (ret)
1086 		goto out_free;
1087 
1088 	if (!mmc->ocr_avail) {
1089 		if (pdata && pdata->ocr_avail)
1090 			mmc->ocr_avail = pdata->ocr_avail;
1091 		else
1092 			mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
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 	ret = clk_prepare_enable(host->clk_per);
1114 	if (ret)
1115 		goto out_free;
1116 
1117 	ret = clk_prepare_enable(host->clk_ipg);
1118 	if (ret)
1119 		goto out_clk_per_put;
1120 
1121 	mxcmci_softreset(host);
1122 
1123 	host->rev_no = mxcmci_readw(host, MMC_REG_REV_NO);
1124 	if (host->rev_no != 0x400) {
1125 		ret = -ENODEV;
1126 		dev_err(mmc_dev(host->mmc), "wrong rev.no. 0x%08x. aborting.\n",
1127 			host->rev_no);
1128 		goto out_clk_put;
1129 	}
1130 
1131 	mmc->f_min = clk_get_rate(host->clk_per) >> 16;
1132 	mmc->f_max = clk_get_rate(host->clk_per) >> 1;
1133 
1134 	/* recommended in data sheet */
1135 	mxcmci_writew(host, 0x2db4, MMC_REG_READ_TO);
1136 
1137 	mxcmci_writel(host, host->default_irq_mask, MMC_REG_INT_CNTR);
1138 
1139 	if (!host->pdata) {
1140 		host->dma = dma_request_slave_channel(&pdev->dev, "rx-tx");
1141 	} else {
1142 		res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1143 		if (res) {
1144 			host->dmareq = res->start;
1145 			host->dma_data.peripheral_type = IMX_DMATYPE_SDHC;
1146 			host->dma_data.priority = DMA_PRIO_LOW;
1147 			host->dma_data.dma_request = host->dmareq;
1148 			dma_cap_zero(mask);
1149 			dma_cap_set(DMA_SLAVE, mask);
1150 			host->dma = dma_request_channel(mask, filter, host);
1151 		}
1152 	}
1153 	if (host->dma)
1154 		mmc->max_seg_size = dma_get_max_seg_size(
1155 				host->dma->device->dev);
1156 	else
1157 		dev_info(mmc_dev(host->mmc), "dma not available. Using PIO\n");
1158 
1159 	INIT_WORK(&host->datawork, mxcmci_datawork);
1160 
1161 	ret = devm_request_irq(&pdev->dev, irq, mxcmci_irq, 0,
1162 			       dev_name(&pdev->dev), host);
1163 	if (ret)
1164 		goto out_free_dma;
1165 
1166 	platform_set_drvdata(pdev, mmc);
1167 
1168 	if (host->pdata && host->pdata->init) {
1169 		ret = host->pdata->init(&pdev->dev, mxcmci_detect_irq,
1170 				host->mmc);
1171 		if (ret)
1172 			goto out_free_dma;
1173 	}
1174 
1175 	timer_setup(&host->watchdog, mxcmci_watchdog, 0);
1176 
1177 	mmc_add_host(mmc);
1178 
1179 	return 0;
1180 
1181 out_free_dma:
1182 	if (host->dma)
1183 		dma_release_channel(host->dma);
1184 
1185 out_clk_put:
1186 	clk_disable_unprepare(host->clk_ipg);
1187 out_clk_per_put:
1188 	clk_disable_unprepare(host->clk_per);
1189 
1190 out_free:
1191 	mmc_free_host(mmc);
1192 
1193 	return ret;
1194 }
1195 
1196 static int mxcmci_remove(struct platform_device *pdev)
1197 {
1198 	struct mmc_host *mmc = platform_get_drvdata(pdev);
1199 	struct mxcmci_host *host = mmc_priv(mmc);
1200 
1201 	mmc_remove_host(mmc);
1202 
1203 	if (host->pdata && host->pdata->exit)
1204 		host->pdata->exit(&pdev->dev, mmc);
1205 
1206 	if (host->dma)
1207 		dma_release_channel(host->dma);
1208 
1209 	clk_disable_unprepare(host->clk_per);
1210 	clk_disable_unprepare(host->clk_ipg);
1211 
1212 	mmc_free_host(mmc);
1213 
1214 	return 0;
1215 }
1216 
1217 #ifdef CONFIG_PM_SLEEP
1218 static int mxcmci_suspend(struct device *dev)
1219 {
1220 	struct mmc_host *mmc = dev_get_drvdata(dev);
1221 	struct mxcmci_host *host = mmc_priv(mmc);
1222 
1223 	clk_disable_unprepare(host->clk_per);
1224 	clk_disable_unprepare(host->clk_ipg);
1225 	return 0;
1226 }
1227 
1228 static int mxcmci_resume(struct device *dev)
1229 {
1230 	struct mmc_host *mmc = dev_get_drvdata(dev);
1231 	struct mxcmci_host *host = mmc_priv(mmc);
1232 	int ret;
1233 
1234 	ret = clk_prepare_enable(host->clk_per);
1235 	if (ret)
1236 		return ret;
1237 
1238 	ret = clk_prepare_enable(host->clk_ipg);
1239 	if (ret)
1240 		clk_disable_unprepare(host->clk_per);
1241 
1242 	return ret;
1243 }
1244 #endif
1245 
1246 static SIMPLE_DEV_PM_OPS(mxcmci_pm_ops, mxcmci_suspend, mxcmci_resume);
1247 
1248 static struct platform_driver mxcmci_driver = {
1249 	.probe		= mxcmci_probe,
1250 	.remove		= mxcmci_remove,
1251 	.id_table	= mxcmci_devtype,
1252 	.driver		= {
1253 		.name		= DRIVER_NAME,
1254 		.pm	= &mxcmci_pm_ops,
1255 		.of_match_table	= mxcmci_of_match,
1256 	}
1257 };
1258 
1259 module_platform_driver(mxcmci_driver);
1260 
1261 MODULE_DESCRIPTION("i.MX Multimedia Card Interface Driver");
1262 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1263 MODULE_LICENSE("GPL");
1264 MODULE_ALIAS("platform:mxc-mmc");
1265