xref: /openbmc/linux/drivers/mmc/host/mxcmmc.c (revision 2c684d89)
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 		*buf = swab32(*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 
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 	int stat, i;
616 
617 	host->data = data;
618 	host->datasize = 0;
619 
620 	if (data->flags & MMC_DATA_READ) {
621 		for_each_sg(data->sg, sg, data->sg_len, i) {
622 			stat = mxcmci_pull(host, sg_virt(sg), sg->length);
623 			if (stat)
624 				return stat;
625 			host->datasize += sg->length;
626 		}
627 	} else {
628 		for_each_sg(data->sg, sg, data->sg_len, i) {
629 			stat = mxcmci_push(host, sg_virt(sg), sg->length);
630 			if (stat)
631 				return stat;
632 			host->datasize += sg->length;
633 		}
634 		stat = mxcmci_poll_status(host, STATUS_WRITE_OP_DONE);
635 		if (stat)
636 			return stat;
637 	}
638 	return 0;
639 }
640 
641 static void mxcmci_datawork(struct work_struct *work)
642 {
643 	struct mxcmci_host *host = container_of(work, struct mxcmci_host,
644 						  datawork);
645 	int datastat = mxcmci_transfer_data(host);
646 
647 	mxcmci_writel(host, STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE,
648 		MMC_REG_STATUS);
649 	mxcmci_finish_data(host, datastat);
650 
651 	if (host->req->stop) {
652 		if (mxcmci_start_cmd(host, host->req->stop, 0)) {
653 			mxcmci_finish_request(host, host->req);
654 			return;
655 		}
656 	} else {
657 		mxcmci_finish_request(host, host->req);
658 	}
659 }
660 
661 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat)
662 {
663 	struct mmc_request *req;
664 	int data_error;
665 	unsigned long flags;
666 
667 	spin_lock_irqsave(&host->lock, flags);
668 
669 	if (!host->data) {
670 		spin_unlock_irqrestore(&host->lock, flags);
671 		return;
672 	}
673 
674 	if (!host->req) {
675 		spin_unlock_irqrestore(&host->lock, flags);
676 		return;
677 	}
678 
679 	req = host->req;
680 	if (!req->stop)
681 		host->req = NULL; /* we will handle finish req below */
682 
683 	data_error = mxcmci_finish_data(host, stat);
684 
685 	spin_unlock_irqrestore(&host->lock, flags);
686 
687 	mxcmci_read_response(host, stat);
688 	host->cmd = NULL;
689 
690 	if (req->stop) {
691 		if (mxcmci_start_cmd(host, req->stop, 0)) {
692 			mxcmci_finish_request(host, req);
693 			return;
694 		}
695 	} else {
696 		mxcmci_finish_request(host, req);
697 	}
698 }
699 
700 static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat)
701 {
702 	mxcmci_read_response(host, stat);
703 	host->cmd = NULL;
704 
705 	if (!host->data && host->req) {
706 		mxcmci_finish_request(host, host->req);
707 		return;
708 	}
709 
710 	/* For the DMA case the DMA engine handles the data transfer
711 	 * automatically. For non DMA we have to do it ourselves.
712 	 * Don't do it in interrupt context though.
713 	 */
714 	if (!mxcmci_use_dma(host) && host->data)
715 		schedule_work(&host->datawork);
716 
717 }
718 
719 static irqreturn_t mxcmci_irq(int irq, void *devid)
720 {
721 	struct mxcmci_host *host = devid;
722 	unsigned long flags;
723 	bool sdio_irq;
724 	u32 stat;
725 
726 	stat = mxcmci_readl(host, MMC_REG_STATUS);
727 	mxcmci_writel(host,
728 		stat & ~(STATUS_SDIO_INT_ACTIVE | STATUS_DATA_TRANS_DONE |
729 			 STATUS_WRITE_OP_DONE),
730 		MMC_REG_STATUS);
731 
732 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
733 
734 	spin_lock_irqsave(&host->lock, flags);
735 	sdio_irq = (stat & STATUS_SDIO_INT_ACTIVE) && host->use_sdio;
736 	spin_unlock_irqrestore(&host->lock, flags);
737 
738 	if (mxcmci_use_dma(host) && (stat & (STATUS_WRITE_OP_DONE)))
739 		mxcmci_writel(host, STATUS_WRITE_OP_DONE, MMC_REG_STATUS);
740 
741 	if (sdio_irq) {
742 		mxcmci_writel(host, STATUS_SDIO_INT_ACTIVE, MMC_REG_STATUS);
743 		mmc_signal_sdio_irq(host->mmc);
744 	}
745 
746 	if (stat & STATUS_END_CMD_RESP)
747 		mxcmci_cmd_done(host, stat);
748 
749 	if (mxcmci_use_dma(host) && (stat & STATUS_WRITE_OP_DONE)) {
750 		del_timer(&host->watchdog);
751 		mxcmci_data_done(host, stat);
752 	}
753 
754 	if (host->default_irq_mask &&
755 		  (stat & (STATUS_CARD_INSERTION | STATUS_CARD_REMOVAL)))
756 		mmc_detect_change(host->mmc, msecs_to_jiffies(200));
757 
758 	return IRQ_HANDLED;
759 }
760 
761 static void mxcmci_request(struct mmc_host *mmc, struct mmc_request *req)
762 {
763 	struct mxcmci_host *host = mmc_priv(mmc);
764 	unsigned int cmdat = host->cmdat;
765 	int error;
766 
767 	WARN_ON(host->req != NULL);
768 
769 	host->req = req;
770 	host->cmdat &= ~CMD_DAT_CONT_INIT;
771 
772 	if (host->dma)
773 		host->do_dma = 1;
774 
775 	if (req->data) {
776 		error = mxcmci_setup_data(host, req->data);
777 		if (error) {
778 			req->cmd->error = error;
779 			goto out;
780 		}
781 
782 
783 		cmdat |= CMD_DAT_CONT_DATA_ENABLE;
784 
785 		if (req->data->flags & MMC_DATA_WRITE)
786 			cmdat |= CMD_DAT_CONT_WRITE;
787 	}
788 
789 	error = mxcmci_start_cmd(host, req->cmd, cmdat);
790 
791 out:
792 	if (error)
793 		mxcmci_finish_request(host, req);
794 }
795 
796 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios)
797 {
798 	unsigned int divider;
799 	int prescaler = 0;
800 	unsigned int clk_in = clk_get_rate(host->clk_per);
801 
802 	while (prescaler <= 0x800) {
803 		for (divider = 1; divider <= 0xF; divider++) {
804 			int x;
805 
806 			x = (clk_in / (divider + 1));
807 
808 			if (prescaler)
809 				x /= (prescaler * 2);
810 
811 			if (x <= clk_ios)
812 				break;
813 		}
814 		if (divider < 0x10)
815 			break;
816 
817 		if (prescaler == 0)
818 			prescaler = 1;
819 		else
820 			prescaler <<= 1;
821 	}
822 
823 	mxcmci_writew(host, (prescaler << 4) | divider, MMC_REG_CLK_RATE);
824 
825 	dev_dbg(mmc_dev(host->mmc), "scaler: %d divider: %d in: %d out: %d\n",
826 			prescaler, divider, clk_in, clk_ios);
827 }
828 
829 static int mxcmci_setup_dma(struct mmc_host *mmc)
830 {
831 	struct mxcmci_host *host = mmc_priv(mmc);
832 	struct dma_slave_config *config = &host->dma_slave_config;
833 
834 	config->dst_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
835 	config->src_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
836 	config->dst_addr_width = 4;
837 	config->src_addr_width = 4;
838 	config->dst_maxburst = host->burstlen;
839 	config->src_maxburst = host->burstlen;
840 	config->device_fc = false;
841 
842 	return dmaengine_slave_config(host->dma, config);
843 }
844 
845 static void mxcmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
846 {
847 	struct mxcmci_host *host = mmc_priv(mmc);
848 	int burstlen, ret;
849 
850 	/*
851 	 * use burstlen of 64 (16 words) in 4 bit mode (--> reg value  0)
852 	 * use burstlen of 16 (4 words) in 1 bit mode (--> reg value 16)
853 	 */
854 	if (ios->bus_width == MMC_BUS_WIDTH_4)
855 		burstlen = 16;
856 	else
857 		burstlen = 4;
858 
859 	if (mxcmci_use_dma(host) && burstlen != host->burstlen) {
860 		host->burstlen = burstlen;
861 		ret = mxcmci_setup_dma(mmc);
862 		if (ret) {
863 			dev_err(mmc_dev(host->mmc),
864 				"failed to config DMA channel. Falling back to PIO\n");
865 			dma_release_channel(host->dma);
866 			host->do_dma = 0;
867 			host->dma = NULL;
868 		}
869 	}
870 
871 	if (ios->bus_width == MMC_BUS_WIDTH_4)
872 		host->cmdat |= CMD_DAT_CONT_BUS_WIDTH_4;
873 	else
874 		host->cmdat &= ~CMD_DAT_CONT_BUS_WIDTH_4;
875 
876 	if (host->power_mode != ios->power_mode) {
877 		host->power_mode = ios->power_mode;
878 		mxcmci_set_power(host, ios->vdd);
879 
880 		if (ios->power_mode == MMC_POWER_ON)
881 			host->cmdat |= CMD_DAT_CONT_INIT;
882 	}
883 
884 	if (ios->clock) {
885 		mxcmci_set_clk_rate(host, ios->clock);
886 		mxcmci_writew(host, STR_STP_CLK_START_CLK, MMC_REG_STR_STP_CLK);
887 	} else {
888 		mxcmci_writew(host, STR_STP_CLK_STOP_CLK, MMC_REG_STR_STP_CLK);
889 	}
890 
891 	host->clock = ios->clock;
892 }
893 
894 static irqreturn_t mxcmci_detect_irq(int irq, void *data)
895 {
896 	struct mmc_host *mmc = data;
897 
898 	dev_dbg(mmc_dev(mmc), "%s\n", __func__);
899 
900 	mmc_detect_change(mmc, msecs_to_jiffies(250));
901 	return IRQ_HANDLED;
902 }
903 
904 static int mxcmci_get_ro(struct mmc_host *mmc)
905 {
906 	struct mxcmci_host *host = mmc_priv(mmc);
907 
908 	if (host->pdata && host->pdata->get_ro)
909 		return !!host->pdata->get_ro(mmc_dev(mmc));
910 	/*
911 	 * If board doesn't support read only detection (no mmc_gpio
912 	 * context or gpio is invalid), then let the mmc core decide
913 	 * what to do.
914 	 */
915 	return mmc_gpio_get_ro(mmc);
916 }
917 
918 static void mxcmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
919 {
920 	struct mxcmci_host *host = mmc_priv(mmc);
921 	unsigned long flags;
922 	u32 int_cntr;
923 
924 	spin_lock_irqsave(&host->lock, flags);
925 	host->use_sdio = enable;
926 	int_cntr = mxcmci_readl(host, MMC_REG_INT_CNTR);
927 
928 	if (enable)
929 		int_cntr |= INT_SDIO_IRQ_EN;
930 	else
931 		int_cntr &= ~INT_SDIO_IRQ_EN;
932 
933 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
934 	spin_unlock_irqrestore(&host->lock, flags);
935 }
936 
937 static void mxcmci_init_card(struct mmc_host *host, struct mmc_card *card)
938 {
939 	struct mxcmci_host *mxcmci = mmc_priv(host);
940 
941 	/*
942 	 * MX3 SoCs have a silicon bug which corrupts CRC calculation of
943 	 * multi-block transfers when connected SDIO peripheral doesn't
944 	 * drive the BUSY line as required by the specs.
945 	 * One way to prevent this is to only allow 1-bit transfers.
946 	 */
947 
948 	if (is_imx31_mmc(mxcmci) && card->type == MMC_TYPE_SDIO)
949 		host->caps &= ~MMC_CAP_4_BIT_DATA;
950 	else
951 		host->caps |= MMC_CAP_4_BIT_DATA;
952 }
953 
954 static bool filter(struct dma_chan *chan, void *param)
955 {
956 	struct mxcmci_host *host = param;
957 
958 	if (!imx_dma_is_general_purpose(chan))
959 		return false;
960 
961 	chan->private = &host->dma_data;
962 
963 	return true;
964 }
965 
966 static void mxcmci_watchdog(unsigned long data)
967 {
968 	struct mmc_host *mmc = (struct mmc_host *)data;
969 	struct mxcmci_host *host = mmc_priv(mmc);
970 	struct mmc_request *req = host->req;
971 	unsigned int stat = mxcmci_readl(host, MMC_REG_STATUS);
972 
973 	if (host->dma_dir == DMA_FROM_DEVICE) {
974 		dmaengine_terminate_all(host->dma);
975 		dev_err(mmc_dev(host->mmc),
976 			"%s: read time out (status = 0x%08x)\n",
977 			__func__, stat);
978 	} else {
979 		dev_err(mmc_dev(host->mmc),
980 			"%s: write time out (status = 0x%08x)\n",
981 			__func__, stat);
982 		mxcmci_softreset(host);
983 	}
984 
985 	/* Mark transfer as erroneus and inform the upper layers */
986 
987 	if (host->data)
988 		host->data->error = -ETIMEDOUT;
989 	host->req = NULL;
990 	host->cmd = NULL;
991 	host->data = NULL;
992 	mmc_request_done(host->mmc, req);
993 }
994 
995 static const struct mmc_host_ops mxcmci_ops = {
996 	.request		= mxcmci_request,
997 	.set_ios		= mxcmci_set_ios,
998 	.get_ro			= mxcmci_get_ro,
999 	.enable_sdio_irq	= mxcmci_enable_sdio_irq,
1000 	.init_card		= mxcmci_init_card,
1001 };
1002 
1003 static int mxcmci_probe(struct platform_device *pdev)
1004 {
1005 	struct mmc_host *mmc;
1006 	struct mxcmci_host *host;
1007 	struct resource *res;
1008 	int ret = 0, irq;
1009 	bool dat3_card_detect = false;
1010 	dma_cap_mask_t mask;
1011 	const struct of_device_id *of_id;
1012 	struct imxmmc_platform_data *pdata = pdev->dev.platform_data;
1013 
1014 	pr_info("i.MX/MPC512x SDHC driver\n");
1015 
1016 	of_id = of_match_device(mxcmci_of_match, &pdev->dev);
1017 
1018 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1019 	irq = platform_get_irq(pdev, 0);
1020 	if (irq < 0)
1021 		return -EINVAL;
1022 
1023 	mmc = mmc_alloc_host(sizeof(*host), &pdev->dev);
1024 	if (!mmc)
1025 		return -ENOMEM;
1026 
1027 	host = mmc_priv(mmc);
1028 
1029 	host->base = devm_ioremap_resource(&pdev->dev, res);
1030 	if (IS_ERR(host->base)) {
1031 		ret = PTR_ERR(host->base);
1032 		goto out_free;
1033 	}
1034 
1035 	host->phys_base = res->start;
1036 
1037 	ret = mmc_of_parse(mmc);
1038 	if (ret)
1039 		goto out_free;
1040 	mmc->ops = &mxcmci_ops;
1041 
1042 	/* For devicetree parsing, the bus width is read from devicetree */
1043 	if (pdata)
1044 		mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
1045 	else
1046 		mmc->caps |= MMC_CAP_SDIO_IRQ;
1047 
1048 	/* MMC core transfer sizes tunable parameters */
1049 	mmc->max_blk_size = 2048;
1050 	mmc->max_blk_count = 65535;
1051 	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
1052 	mmc->max_seg_size = mmc->max_req_size;
1053 
1054 	if (of_id) {
1055 		const struct platform_device_id *id_entry = of_id->data;
1056 		host->devtype = id_entry->driver_data;
1057 	} else {
1058 		host->devtype = pdev->id_entry->driver_data;
1059 	}
1060 
1061 	/* adjust max_segs after devtype detection */
1062 	if (!is_mpc512x_mmc(host))
1063 		mmc->max_segs = 64;
1064 
1065 	host->mmc = mmc;
1066 	host->pdata = pdata;
1067 	spin_lock_init(&host->lock);
1068 
1069 	if (pdata)
1070 		dat3_card_detect = pdata->dat3_card_detect;
1071 	else if (!(mmc->caps & MMC_CAP_NONREMOVABLE)
1072 			&& !of_property_read_bool(pdev->dev.of_node, "cd-gpios"))
1073 		dat3_card_detect = true;
1074 
1075 	ret = mmc_regulator_get_supply(mmc);
1076 	if (ret == -EPROBE_DEFER)
1077 		goto out_free;
1078 
1079 	if (!mmc->ocr_avail) {
1080 		if (pdata && pdata->ocr_avail)
1081 			mmc->ocr_avail = pdata->ocr_avail;
1082 		else
1083 			mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
1084 	}
1085 
1086 	if (dat3_card_detect)
1087 		host->default_irq_mask =
1088 			INT_CARD_INSERTION_EN | INT_CARD_REMOVAL_EN;
1089 	else
1090 		host->default_irq_mask = 0;
1091 
1092 	host->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1093 	if (IS_ERR(host->clk_ipg)) {
1094 		ret = PTR_ERR(host->clk_ipg);
1095 		goto out_free;
1096 	}
1097 
1098 	host->clk_per = devm_clk_get(&pdev->dev, "per");
1099 	if (IS_ERR(host->clk_per)) {
1100 		ret = PTR_ERR(host->clk_per);
1101 		goto out_free;
1102 	}
1103 
1104 	clk_prepare_enable(host->clk_per);
1105 	clk_prepare_enable(host->clk_ipg);
1106 
1107 	mxcmci_softreset(host);
1108 
1109 	host->rev_no = mxcmci_readw(host, MMC_REG_REV_NO);
1110 	if (host->rev_no != 0x400) {
1111 		ret = -ENODEV;
1112 		dev_err(mmc_dev(host->mmc), "wrong rev.no. 0x%08x. aborting.\n",
1113 			host->rev_no);
1114 		goto out_clk_put;
1115 	}
1116 
1117 	mmc->f_min = clk_get_rate(host->clk_per) >> 16;
1118 	mmc->f_max = clk_get_rate(host->clk_per) >> 1;
1119 
1120 	/* recommended in data sheet */
1121 	mxcmci_writew(host, 0x2db4, MMC_REG_READ_TO);
1122 
1123 	mxcmci_writel(host, host->default_irq_mask, MMC_REG_INT_CNTR);
1124 
1125 	if (!host->pdata) {
1126 		host->dma = dma_request_slave_channel(&pdev->dev, "rx-tx");
1127 	} else {
1128 		res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1129 		if (res) {
1130 			host->dmareq = res->start;
1131 			host->dma_data.peripheral_type = IMX_DMATYPE_SDHC;
1132 			host->dma_data.priority = DMA_PRIO_LOW;
1133 			host->dma_data.dma_request = host->dmareq;
1134 			dma_cap_zero(mask);
1135 			dma_cap_set(DMA_SLAVE, mask);
1136 			host->dma = dma_request_channel(mask, filter, host);
1137 		}
1138 	}
1139 	if (host->dma)
1140 		mmc->max_seg_size = dma_get_max_seg_size(
1141 				host->dma->device->dev);
1142 	else
1143 		dev_info(mmc_dev(host->mmc), "dma not available. Using PIO\n");
1144 
1145 	INIT_WORK(&host->datawork, mxcmci_datawork);
1146 
1147 	ret = devm_request_irq(&pdev->dev, irq, mxcmci_irq, 0,
1148 			       dev_name(&pdev->dev), host);
1149 	if (ret)
1150 		goto out_free_dma;
1151 
1152 	platform_set_drvdata(pdev, mmc);
1153 
1154 	if (host->pdata && host->pdata->init) {
1155 		ret = host->pdata->init(&pdev->dev, mxcmci_detect_irq,
1156 				host->mmc);
1157 		if (ret)
1158 			goto out_free_dma;
1159 	}
1160 
1161 	init_timer(&host->watchdog);
1162 	host->watchdog.function = &mxcmci_watchdog;
1163 	host->watchdog.data = (unsigned long)mmc;
1164 
1165 	mmc_add_host(mmc);
1166 
1167 	return 0;
1168 
1169 out_free_dma:
1170 	if (host->dma)
1171 		dma_release_channel(host->dma);
1172 
1173 out_clk_put:
1174 	clk_disable_unprepare(host->clk_per);
1175 	clk_disable_unprepare(host->clk_ipg);
1176 
1177 out_free:
1178 	mmc_free_host(mmc);
1179 
1180 	return ret;
1181 }
1182 
1183 static int mxcmci_remove(struct platform_device *pdev)
1184 {
1185 	struct mmc_host *mmc = platform_get_drvdata(pdev);
1186 	struct mxcmci_host *host = mmc_priv(mmc);
1187 
1188 	mmc_remove_host(mmc);
1189 
1190 	if (host->pdata && host->pdata->exit)
1191 		host->pdata->exit(&pdev->dev, mmc);
1192 
1193 	if (host->dma)
1194 		dma_release_channel(host->dma);
1195 
1196 	clk_disable_unprepare(host->clk_per);
1197 	clk_disable_unprepare(host->clk_ipg);
1198 
1199 	mmc_free_host(mmc);
1200 
1201 	return 0;
1202 }
1203 
1204 static int __maybe_unused mxcmci_suspend(struct device *dev)
1205 {
1206 	struct mmc_host *mmc = dev_get_drvdata(dev);
1207 	struct mxcmci_host *host = mmc_priv(mmc);
1208 
1209 	clk_disable_unprepare(host->clk_per);
1210 	clk_disable_unprepare(host->clk_ipg);
1211 	return 0;
1212 }
1213 
1214 static int __maybe_unused mxcmci_resume(struct device *dev)
1215 {
1216 	struct mmc_host *mmc = dev_get_drvdata(dev);
1217 	struct mxcmci_host *host = mmc_priv(mmc);
1218 
1219 	clk_prepare_enable(host->clk_per);
1220 	clk_prepare_enable(host->clk_ipg);
1221 	return 0;
1222 }
1223 
1224 static SIMPLE_DEV_PM_OPS(mxcmci_pm_ops, mxcmci_suspend, mxcmci_resume);
1225 
1226 static struct platform_driver mxcmci_driver = {
1227 	.probe		= mxcmci_probe,
1228 	.remove		= mxcmci_remove,
1229 	.id_table	= mxcmci_devtype,
1230 	.driver		= {
1231 		.name		= DRIVER_NAME,
1232 		.pm	= &mxcmci_pm_ops,
1233 		.of_match_table	= mxcmci_of_match,
1234 	}
1235 };
1236 
1237 module_platform_driver(mxcmci_driver);
1238 
1239 MODULE_DESCRIPTION("i.MX Multimedia Card Interface Driver");
1240 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1241 MODULE_LICENSE("GPL");
1242 MODULE_ALIAS("platform:mxc-mmc");
1243