xref: /openbmc/linux/drivers/mmc/host/omap.c (revision ebd09753)
1 /*
2  *  linux/drivers/mmc/host/omap.c
3  *
4  *  Copyright (C) 2004 Nokia Corporation
5  *  Written by Tuukka Tikkanen and Juha Yrjölä<juha.yrjola@nokia.com>
6  *  Misc hacks here and there by Tony Lindgren <tony@atomide.com>
7  *  Other hacks (DMA, SD, etc) by David Brownell
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  */
13 
14 #include <linux/module.h>
15 #include <linux/moduleparam.h>
16 #include <linux/init.h>
17 #include <linux/ioport.h>
18 #include <linux/platform_device.h>
19 #include <linux/interrupt.h>
20 #include <linux/dmaengine.h>
21 #include <linux/dma-mapping.h>
22 #include <linux/delay.h>
23 #include <linux/spinlock.h>
24 #include <linux/timer.h>
25 #include <linux/of.h>
26 #include <linux/mmc/host.h>
27 #include <linux/mmc/card.h>
28 #include <linux/mmc/mmc.h>
29 #include <linux/clk.h>
30 #include <linux/scatterlist.h>
31 #include <linux/slab.h>
32 #include <linux/platform_data/mmc-omap.h>
33 
34 
35 #define	OMAP_MMC_REG_CMD	0x00
36 #define	OMAP_MMC_REG_ARGL	0x01
37 #define	OMAP_MMC_REG_ARGH	0x02
38 #define	OMAP_MMC_REG_CON	0x03
39 #define	OMAP_MMC_REG_STAT	0x04
40 #define	OMAP_MMC_REG_IE		0x05
41 #define	OMAP_MMC_REG_CTO	0x06
42 #define	OMAP_MMC_REG_DTO	0x07
43 #define	OMAP_MMC_REG_DATA	0x08
44 #define	OMAP_MMC_REG_BLEN	0x09
45 #define	OMAP_MMC_REG_NBLK	0x0a
46 #define	OMAP_MMC_REG_BUF	0x0b
47 #define	OMAP_MMC_REG_SDIO	0x0d
48 #define	OMAP_MMC_REG_REV	0x0f
49 #define	OMAP_MMC_REG_RSP0	0x10
50 #define	OMAP_MMC_REG_RSP1	0x11
51 #define	OMAP_MMC_REG_RSP2	0x12
52 #define	OMAP_MMC_REG_RSP3	0x13
53 #define	OMAP_MMC_REG_RSP4	0x14
54 #define	OMAP_MMC_REG_RSP5	0x15
55 #define	OMAP_MMC_REG_RSP6	0x16
56 #define	OMAP_MMC_REG_RSP7	0x17
57 #define	OMAP_MMC_REG_IOSR	0x18
58 #define	OMAP_MMC_REG_SYSC	0x19
59 #define	OMAP_MMC_REG_SYSS	0x1a
60 
61 #define	OMAP_MMC_STAT_CARD_ERR		(1 << 14)
62 #define	OMAP_MMC_STAT_CARD_IRQ		(1 << 13)
63 #define	OMAP_MMC_STAT_OCR_BUSY		(1 << 12)
64 #define	OMAP_MMC_STAT_A_EMPTY		(1 << 11)
65 #define	OMAP_MMC_STAT_A_FULL		(1 << 10)
66 #define	OMAP_MMC_STAT_CMD_CRC		(1 <<  8)
67 #define	OMAP_MMC_STAT_CMD_TOUT		(1 <<  7)
68 #define	OMAP_MMC_STAT_DATA_CRC		(1 <<  6)
69 #define	OMAP_MMC_STAT_DATA_TOUT		(1 <<  5)
70 #define	OMAP_MMC_STAT_END_BUSY		(1 <<  4)
71 #define	OMAP_MMC_STAT_END_OF_DATA	(1 <<  3)
72 #define	OMAP_MMC_STAT_CARD_BUSY		(1 <<  2)
73 #define	OMAP_MMC_STAT_END_OF_CMD	(1 <<  0)
74 
75 #define mmc_omap7xx()	(host->features & MMC_OMAP7XX)
76 #define mmc_omap15xx()	(host->features & MMC_OMAP15XX)
77 #define mmc_omap16xx()	(host->features & MMC_OMAP16XX)
78 #define MMC_OMAP1_MASK	(MMC_OMAP7XX | MMC_OMAP15XX | MMC_OMAP16XX)
79 #define mmc_omap1()	(host->features & MMC_OMAP1_MASK)
80 #define mmc_omap2()	(!mmc_omap1())
81 
82 #define OMAP_MMC_REG(host, reg)		(OMAP_MMC_REG_##reg << (host)->reg_shift)
83 #define OMAP_MMC_READ(host, reg)	__raw_readw((host)->virt_base + OMAP_MMC_REG(host, reg))
84 #define OMAP_MMC_WRITE(host, reg, val)	__raw_writew((val), (host)->virt_base + OMAP_MMC_REG(host, reg))
85 
86 /*
87  * Command types
88  */
89 #define OMAP_MMC_CMDTYPE_BC	0
90 #define OMAP_MMC_CMDTYPE_BCR	1
91 #define OMAP_MMC_CMDTYPE_AC	2
92 #define OMAP_MMC_CMDTYPE_ADTC	3
93 
94 #define DRIVER_NAME "mmci-omap"
95 
96 /* Specifies how often in millisecs to poll for card status changes
97  * when the cover switch is open */
98 #define OMAP_MMC_COVER_POLL_DELAY	500
99 
100 struct mmc_omap_host;
101 
102 struct mmc_omap_slot {
103 	int			id;
104 	unsigned int		vdd;
105 	u16			saved_con;
106 	u16			bus_mode;
107 	unsigned int		fclk_freq;
108 
109 	struct tasklet_struct	cover_tasklet;
110 	struct timer_list       cover_timer;
111 	unsigned		cover_open;
112 
113 	struct mmc_request      *mrq;
114 	struct mmc_omap_host    *host;
115 	struct mmc_host		*mmc;
116 	struct omap_mmc_slot_data *pdata;
117 };
118 
119 struct mmc_omap_host {
120 	int			initialized;
121 	struct mmc_request *	mrq;
122 	struct mmc_command *	cmd;
123 	struct mmc_data *	data;
124 	struct mmc_host *	mmc;
125 	struct device *		dev;
126 	unsigned char		id; /* 16xx chips have 2 MMC blocks */
127 	struct clk *		iclk;
128 	struct clk *		fclk;
129 	struct dma_chan		*dma_rx;
130 	u32			dma_rx_burst;
131 	struct dma_chan		*dma_tx;
132 	u32			dma_tx_burst;
133 	void __iomem		*virt_base;
134 	unsigned int		phys_base;
135 	int			irq;
136 	unsigned char		bus_mode;
137 	unsigned int		reg_shift;
138 
139 	struct work_struct	cmd_abort_work;
140 	unsigned		abort:1;
141 	struct timer_list	cmd_abort_timer;
142 
143 	struct work_struct      slot_release_work;
144 	struct mmc_omap_slot    *next_slot;
145 	struct work_struct      send_stop_work;
146 	struct mmc_data		*stop_data;
147 
148 	unsigned int		sg_len;
149 	int			sg_idx;
150 	u16 *			buffer;
151 	u32			buffer_bytes_left;
152 	u32			total_bytes_left;
153 
154 	unsigned		features;
155 	unsigned		brs_received:1, dma_done:1;
156 	unsigned		dma_in_use:1;
157 	spinlock_t		dma_lock;
158 
159 	struct mmc_omap_slot    *slots[OMAP_MMC_MAX_SLOTS];
160 	struct mmc_omap_slot    *current_slot;
161 	spinlock_t              slot_lock;
162 	wait_queue_head_t       slot_wq;
163 	int                     nr_slots;
164 
165 	struct timer_list       clk_timer;
166 	spinlock_t		clk_lock;     /* for changing enabled state */
167 	unsigned int            fclk_enabled:1;
168 	struct workqueue_struct *mmc_omap_wq;
169 
170 	struct omap_mmc_platform_data *pdata;
171 };
172 
173 
174 static void mmc_omap_fclk_offdelay(struct mmc_omap_slot *slot)
175 {
176 	unsigned long tick_ns;
177 
178 	if (slot != NULL && slot->host->fclk_enabled && slot->fclk_freq > 0) {
179 		tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, slot->fclk_freq);
180 		ndelay(8 * tick_ns);
181 	}
182 }
183 
184 static void mmc_omap_fclk_enable(struct mmc_omap_host *host, unsigned int enable)
185 {
186 	unsigned long flags;
187 
188 	spin_lock_irqsave(&host->clk_lock, flags);
189 	if (host->fclk_enabled != enable) {
190 		host->fclk_enabled = enable;
191 		if (enable)
192 			clk_enable(host->fclk);
193 		else
194 			clk_disable(host->fclk);
195 	}
196 	spin_unlock_irqrestore(&host->clk_lock, flags);
197 }
198 
199 static void mmc_omap_select_slot(struct mmc_omap_slot *slot, int claimed)
200 {
201 	struct mmc_omap_host *host = slot->host;
202 	unsigned long flags;
203 
204 	if (claimed)
205 		goto no_claim;
206 	spin_lock_irqsave(&host->slot_lock, flags);
207 	while (host->mmc != NULL) {
208 		spin_unlock_irqrestore(&host->slot_lock, flags);
209 		wait_event(host->slot_wq, host->mmc == NULL);
210 		spin_lock_irqsave(&host->slot_lock, flags);
211 	}
212 	host->mmc = slot->mmc;
213 	spin_unlock_irqrestore(&host->slot_lock, flags);
214 no_claim:
215 	del_timer(&host->clk_timer);
216 	if (host->current_slot != slot || !claimed)
217 		mmc_omap_fclk_offdelay(host->current_slot);
218 
219 	if (host->current_slot != slot) {
220 		OMAP_MMC_WRITE(host, CON, slot->saved_con & 0xFC00);
221 		if (host->pdata->switch_slot != NULL)
222 			host->pdata->switch_slot(mmc_dev(slot->mmc), slot->id);
223 		host->current_slot = slot;
224 	}
225 
226 	if (claimed) {
227 		mmc_omap_fclk_enable(host, 1);
228 
229 		/* Doing the dummy read here seems to work around some bug
230 		 * at least in OMAP24xx silicon where the command would not
231 		 * start after writing the CMD register. Sigh. */
232 		OMAP_MMC_READ(host, CON);
233 
234 		OMAP_MMC_WRITE(host, CON, slot->saved_con);
235 	} else
236 		mmc_omap_fclk_enable(host, 0);
237 }
238 
239 static void mmc_omap_start_request(struct mmc_omap_host *host,
240 				   struct mmc_request *req);
241 
242 static void mmc_omap_slot_release_work(struct work_struct *work)
243 {
244 	struct mmc_omap_host *host = container_of(work, struct mmc_omap_host,
245 						  slot_release_work);
246 	struct mmc_omap_slot *next_slot = host->next_slot;
247 	struct mmc_request *rq;
248 
249 	host->next_slot = NULL;
250 	mmc_omap_select_slot(next_slot, 1);
251 
252 	rq = next_slot->mrq;
253 	next_slot->mrq = NULL;
254 	mmc_omap_start_request(host, rq);
255 }
256 
257 static void mmc_omap_release_slot(struct mmc_omap_slot *slot, int clk_enabled)
258 {
259 	struct mmc_omap_host *host = slot->host;
260 	unsigned long flags;
261 	int i;
262 
263 	BUG_ON(slot == NULL || host->mmc == NULL);
264 
265 	if (clk_enabled)
266 		/* Keeps clock running for at least 8 cycles on valid freq */
267 		mod_timer(&host->clk_timer, jiffies  + HZ/10);
268 	else {
269 		del_timer(&host->clk_timer);
270 		mmc_omap_fclk_offdelay(slot);
271 		mmc_omap_fclk_enable(host, 0);
272 	}
273 
274 	spin_lock_irqsave(&host->slot_lock, flags);
275 	/* Check for any pending requests */
276 	for (i = 0; i < host->nr_slots; i++) {
277 		struct mmc_omap_slot *new_slot;
278 
279 		if (host->slots[i] == NULL || host->slots[i]->mrq == NULL)
280 			continue;
281 
282 		BUG_ON(host->next_slot != NULL);
283 		new_slot = host->slots[i];
284 		/* The current slot should not have a request in queue */
285 		BUG_ON(new_slot == host->current_slot);
286 
287 		host->next_slot = new_slot;
288 		host->mmc = new_slot->mmc;
289 		spin_unlock_irqrestore(&host->slot_lock, flags);
290 		queue_work(host->mmc_omap_wq, &host->slot_release_work);
291 		return;
292 	}
293 
294 	host->mmc = NULL;
295 	wake_up(&host->slot_wq);
296 	spin_unlock_irqrestore(&host->slot_lock, flags);
297 }
298 
299 static inline
300 int mmc_omap_cover_is_open(struct mmc_omap_slot *slot)
301 {
302 	if (slot->pdata->get_cover_state)
303 		return slot->pdata->get_cover_state(mmc_dev(slot->mmc),
304 						    slot->id);
305 	return 0;
306 }
307 
308 static ssize_t
309 mmc_omap_show_cover_switch(struct device *dev, struct device_attribute *attr,
310 			   char *buf)
311 {
312 	struct mmc_host *mmc = container_of(dev, struct mmc_host, class_dev);
313 	struct mmc_omap_slot *slot = mmc_priv(mmc);
314 
315 	return sprintf(buf, "%s\n", mmc_omap_cover_is_open(slot) ? "open" :
316 		       "closed");
317 }
318 
319 static DEVICE_ATTR(cover_switch, S_IRUGO, mmc_omap_show_cover_switch, NULL);
320 
321 static ssize_t
322 mmc_omap_show_slot_name(struct device *dev, struct device_attribute *attr,
323 			char *buf)
324 {
325 	struct mmc_host *mmc = container_of(dev, struct mmc_host, class_dev);
326 	struct mmc_omap_slot *slot = mmc_priv(mmc);
327 
328 	return sprintf(buf, "%s\n", slot->pdata->name);
329 }
330 
331 static DEVICE_ATTR(slot_name, S_IRUGO, mmc_omap_show_slot_name, NULL);
332 
333 static void
334 mmc_omap_start_command(struct mmc_omap_host *host, struct mmc_command *cmd)
335 {
336 	u32 cmdreg;
337 	u32 resptype;
338 	u32 cmdtype;
339 	u16 irq_mask;
340 
341 	host->cmd = cmd;
342 
343 	resptype = 0;
344 	cmdtype = 0;
345 
346 	/* Our hardware needs to know exact type */
347 	switch (mmc_resp_type(cmd)) {
348 	case MMC_RSP_NONE:
349 		break;
350 	case MMC_RSP_R1:
351 	case MMC_RSP_R1B:
352 		/* resp 1, 1b, 6, 7 */
353 		resptype = 1;
354 		break;
355 	case MMC_RSP_R2:
356 		resptype = 2;
357 		break;
358 	case MMC_RSP_R3:
359 		resptype = 3;
360 		break;
361 	default:
362 		dev_err(mmc_dev(host->mmc), "Invalid response type: %04x\n", mmc_resp_type(cmd));
363 		break;
364 	}
365 
366 	if (mmc_cmd_type(cmd) == MMC_CMD_ADTC) {
367 		cmdtype = OMAP_MMC_CMDTYPE_ADTC;
368 	} else if (mmc_cmd_type(cmd) == MMC_CMD_BC) {
369 		cmdtype = OMAP_MMC_CMDTYPE_BC;
370 	} else if (mmc_cmd_type(cmd) == MMC_CMD_BCR) {
371 		cmdtype = OMAP_MMC_CMDTYPE_BCR;
372 	} else {
373 		cmdtype = OMAP_MMC_CMDTYPE_AC;
374 	}
375 
376 	cmdreg = cmd->opcode | (resptype << 8) | (cmdtype << 12);
377 
378 	if (host->current_slot->bus_mode == MMC_BUSMODE_OPENDRAIN)
379 		cmdreg |= 1 << 6;
380 
381 	if (cmd->flags & MMC_RSP_BUSY)
382 		cmdreg |= 1 << 11;
383 
384 	if (host->data && !(host->data->flags & MMC_DATA_WRITE))
385 		cmdreg |= 1 << 15;
386 
387 	mod_timer(&host->cmd_abort_timer, jiffies + HZ/2);
388 
389 	OMAP_MMC_WRITE(host, CTO, 200);
390 	OMAP_MMC_WRITE(host, ARGL, cmd->arg & 0xffff);
391 	OMAP_MMC_WRITE(host, ARGH, cmd->arg >> 16);
392 	irq_mask = OMAP_MMC_STAT_A_EMPTY    | OMAP_MMC_STAT_A_FULL    |
393 		   OMAP_MMC_STAT_CMD_CRC    | OMAP_MMC_STAT_CMD_TOUT  |
394 		   OMAP_MMC_STAT_DATA_CRC   | OMAP_MMC_STAT_DATA_TOUT |
395 		   OMAP_MMC_STAT_END_OF_CMD | OMAP_MMC_STAT_CARD_ERR  |
396 		   OMAP_MMC_STAT_END_OF_DATA;
397 	if (cmd->opcode == MMC_ERASE)
398 		irq_mask &= ~OMAP_MMC_STAT_DATA_TOUT;
399 	OMAP_MMC_WRITE(host, IE, irq_mask);
400 	OMAP_MMC_WRITE(host, CMD, cmdreg);
401 }
402 
403 static void
404 mmc_omap_release_dma(struct mmc_omap_host *host, struct mmc_data *data,
405 		     int abort)
406 {
407 	enum dma_data_direction dma_data_dir;
408 	struct device *dev = mmc_dev(host->mmc);
409 	struct dma_chan *c;
410 
411 	if (data->flags & MMC_DATA_WRITE) {
412 		dma_data_dir = DMA_TO_DEVICE;
413 		c = host->dma_tx;
414 	} else {
415 		dma_data_dir = DMA_FROM_DEVICE;
416 		c = host->dma_rx;
417 	}
418 	if (c) {
419 		if (data->error) {
420 			dmaengine_terminate_all(c);
421 			/* Claim nothing transferred on error... */
422 			data->bytes_xfered = 0;
423 		}
424 		dev = c->device->dev;
425 	}
426 	dma_unmap_sg(dev, data->sg, host->sg_len, dma_data_dir);
427 }
428 
429 static void mmc_omap_send_stop_work(struct work_struct *work)
430 {
431 	struct mmc_omap_host *host = container_of(work, struct mmc_omap_host,
432 						  send_stop_work);
433 	struct mmc_omap_slot *slot = host->current_slot;
434 	struct mmc_data *data = host->stop_data;
435 	unsigned long tick_ns;
436 
437 	tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, slot->fclk_freq);
438 	ndelay(8*tick_ns);
439 
440 	mmc_omap_start_command(host, data->stop);
441 }
442 
443 static void
444 mmc_omap_xfer_done(struct mmc_omap_host *host, struct mmc_data *data)
445 {
446 	if (host->dma_in_use)
447 		mmc_omap_release_dma(host, data, data->error);
448 
449 	host->data = NULL;
450 	host->sg_len = 0;
451 
452 	/* NOTE:  MMC layer will sometimes poll-wait CMD13 next, issuing
453 	 * dozens of requests until the card finishes writing data.
454 	 * It'd be cheaper to just wait till an EOFB interrupt arrives...
455 	 */
456 
457 	if (!data->stop) {
458 		struct mmc_host *mmc;
459 
460 		host->mrq = NULL;
461 		mmc = host->mmc;
462 		mmc_omap_release_slot(host->current_slot, 1);
463 		mmc_request_done(mmc, data->mrq);
464 		return;
465 	}
466 
467 	host->stop_data = data;
468 	queue_work(host->mmc_omap_wq, &host->send_stop_work);
469 }
470 
471 static void
472 mmc_omap_send_abort(struct mmc_omap_host *host, int maxloops)
473 {
474 	struct mmc_omap_slot *slot = host->current_slot;
475 	unsigned int restarts, passes, timeout;
476 	u16 stat = 0;
477 
478 	/* Sending abort takes 80 clocks. Have some extra and round up */
479 	timeout = DIV_ROUND_UP(120 * USEC_PER_SEC, slot->fclk_freq);
480 	restarts = 0;
481 	while (restarts < maxloops) {
482 		OMAP_MMC_WRITE(host, STAT, 0xFFFF);
483 		OMAP_MMC_WRITE(host, CMD, (3 << 12) | (1 << 7));
484 
485 		passes = 0;
486 		while (passes < timeout) {
487 			stat = OMAP_MMC_READ(host, STAT);
488 			if (stat & OMAP_MMC_STAT_END_OF_CMD)
489 				goto out;
490 			udelay(1);
491 			passes++;
492 		}
493 
494 		restarts++;
495 	}
496 out:
497 	OMAP_MMC_WRITE(host, STAT, stat);
498 }
499 
500 static void
501 mmc_omap_abort_xfer(struct mmc_omap_host *host, struct mmc_data *data)
502 {
503 	if (host->dma_in_use)
504 		mmc_omap_release_dma(host, data, 1);
505 
506 	host->data = NULL;
507 	host->sg_len = 0;
508 
509 	mmc_omap_send_abort(host, 10000);
510 }
511 
512 static void
513 mmc_omap_end_of_data(struct mmc_omap_host *host, struct mmc_data *data)
514 {
515 	unsigned long flags;
516 	int done;
517 
518 	if (!host->dma_in_use) {
519 		mmc_omap_xfer_done(host, data);
520 		return;
521 	}
522 	done = 0;
523 	spin_lock_irqsave(&host->dma_lock, flags);
524 	if (host->dma_done)
525 		done = 1;
526 	else
527 		host->brs_received = 1;
528 	spin_unlock_irqrestore(&host->dma_lock, flags);
529 	if (done)
530 		mmc_omap_xfer_done(host, data);
531 }
532 
533 static void
534 mmc_omap_dma_done(struct mmc_omap_host *host, struct mmc_data *data)
535 {
536 	unsigned long flags;
537 	int done;
538 
539 	done = 0;
540 	spin_lock_irqsave(&host->dma_lock, flags);
541 	if (host->brs_received)
542 		done = 1;
543 	else
544 		host->dma_done = 1;
545 	spin_unlock_irqrestore(&host->dma_lock, flags);
546 	if (done)
547 		mmc_omap_xfer_done(host, data);
548 }
549 
550 static void
551 mmc_omap_cmd_done(struct mmc_omap_host *host, struct mmc_command *cmd)
552 {
553 	host->cmd = NULL;
554 
555 	del_timer(&host->cmd_abort_timer);
556 
557 	if (cmd->flags & MMC_RSP_PRESENT) {
558 		if (cmd->flags & MMC_RSP_136) {
559 			/* response type 2 */
560 			cmd->resp[3] =
561 				OMAP_MMC_READ(host, RSP0) |
562 				(OMAP_MMC_READ(host, RSP1) << 16);
563 			cmd->resp[2] =
564 				OMAP_MMC_READ(host, RSP2) |
565 				(OMAP_MMC_READ(host, RSP3) << 16);
566 			cmd->resp[1] =
567 				OMAP_MMC_READ(host, RSP4) |
568 				(OMAP_MMC_READ(host, RSP5) << 16);
569 			cmd->resp[0] =
570 				OMAP_MMC_READ(host, RSP6) |
571 				(OMAP_MMC_READ(host, RSP7) << 16);
572 		} else {
573 			/* response types 1, 1b, 3, 4, 5, 6 */
574 			cmd->resp[0] =
575 				OMAP_MMC_READ(host, RSP6) |
576 				(OMAP_MMC_READ(host, RSP7) << 16);
577 		}
578 	}
579 
580 	if (host->data == NULL || cmd->error) {
581 		struct mmc_host *mmc;
582 
583 		if (host->data != NULL)
584 			mmc_omap_abort_xfer(host, host->data);
585 		host->mrq = NULL;
586 		mmc = host->mmc;
587 		mmc_omap_release_slot(host->current_slot, 1);
588 		mmc_request_done(mmc, cmd->mrq);
589 	}
590 }
591 
592 /*
593  * Abort stuck command. Can occur when card is removed while it is being
594  * read.
595  */
596 static void mmc_omap_abort_command(struct work_struct *work)
597 {
598 	struct mmc_omap_host *host = container_of(work, struct mmc_omap_host,
599 						  cmd_abort_work);
600 	BUG_ON(!host->cmd);
601 
602 	dev_dbg(mmc_dev(host->mmc), "Aborting stuck command CMD%d\n",
603 		host->cmd->opcode);
604 
605 	if (host->cmd->error == 0)
606 		host->cmd->error = -ETIMEDOUT;
607 
608 	if (host->data == NULL) {
609 		struct mmc_command *cmd;
610 		struct mmc_host    *mmc;
611 
612 		cmd = host->cmd;
613 		host->cmd = NULL;
614 		mmc_omap_send_abort(host, 10000);
615 
616 		host->mrq = NULL;
617 		mmc = host->mmc;
618 		mmc_omap_release_slot(host->current_slot, 1);
619 		mmc_request_done(mmc, cmd->mrq);
620 	} else
621 		mmc_omap_cmd_done(host, host->cmd);
622 
623 	host->abort = 0;
624 	enable_irq(host->irq);
625 }
626 
627 static void
628 mmc_omap_cmd_timer(struct timer_list *t)
629 {
630 	struct mmc_omap_host *host = from_timer(host, t, cmd_abort_timer);
631 	unsigned long flags;
632 
633 	spin_lock_irqsave(&host->slot_lock, flags);
634 	if (host->cmd != NULL && !host->abort) {
635 		OMAP_MMC_WRITE(host, IE, 0);
636 		disable_irq(host->irq);
637 		host->abort = 1;
638 		queue_work(host->mmc_omap_wq, &host->cmd_abort_work);
639 	}
640 	spin_unlock_irqrestore(&host->slot_lock, flags);
641 }
642 
643 /* PIO only */
644 static void
645 mmc_omap_sg_to_buf(struct mmc_omap_host *host)
646 {
647 	struct scatterlist *sg;
648 
649 	sg = host->data->sg + host->sg_idx;
650 	host->buffer_bytes_left = sg->length;
651 	host->buffer = sg_virt(sg);
652 	if (host->buffer_bytes_left > host->total_bytes_left)
653 		host->buffer_bytes_left = host->total_bytes_left;
654 }
655 
656 static void
657 mmc_omap_clk_timer(struct timer_list *t)
658 {
659 	struct mmc_omap_host *host = from_timer(host, t, clk_timer);
660 
661 	mmc_omap_fclk_enable(host, 0);
662 }
663 
664 /* PIO only */
665 static void
666 mmc_omap_xfer_data(struct mmc_omap_host *host, int write)
667 {
668 	int n, nwords;
669 
670 	if (host->buffer_bytes_left == 0) {
671 		host->sg_idx++;
672 		BUG_ON(host->sg_idx == host->sg_len);
673 		mmc_omap_sg_to_buf(host);
674 	}
675 	n = 64;
676 	if (n > host->buffer_bytes_left)
677 		n = host->buffer_bytes_left;
678 
679 	/* Round up to handle odd number of bytes to transfer */
680 	nwords = DIV_ROUND_UP(n, 2);
681 
682 	host->buffer_bytes_left -= n;
683 	host->total_bytes_left -= n;
684 	host->data->bytes_xfered += n;
685 
686 	if (write) {
687 		__raw_writesw(host->virt_base + OMAP_MMC_REG(host, DATA),
688 			      host->buffer, nwords);
689 	} else {
690 		__raw_readsw(host->virt_base + OMAP_MMC_REG(host, DATA),
691 			     host->buffer, nwords);
692 	}
693 
694 	host->buffer += nwords;
695 }
696 
697 #ifdef CONFIG_MMC_DEBUG
698 static void mmc_omap_report_irq(struct mmc_omap_host *host, u16 status)
699 {
700 	static const char *mmc_omap_status_bits[] = {
701 		"EOC", "CD", "CB", "BRS", "EOFB", "DTO", "DCRC", "CTO",
702 		"CCRC", "CRW", "AF", "AE", "OCRB", "CIRQ", "CERR"
703 	};
704 	int i;
705 	char res[64], *buf = res;
706 
707 	buf += sprintf(buf, "MMC IRQ 0x%x:", status);
708 
709 	for (i = 0; i < ARRAY_SIZE(mmc_omap_status_bits); i++)
710 		if (status & (1 << i))
711 			buf += sprintf(buf, " %s", mmc_omap_status_bits[i]);
712 	dev_vdbg(mmc_dev(host->mmc), "%s\n", res);
713 }
714 #else
715 static void mmc_omap_report_irq(struct mmc_omap_host *host, u16 status)
716 {
717 }
718 #endif
719 
720 
721 static irqreturn_t mmc_omap_irq(int irq, void *dev_id)
722 {
723 	struct mmc_omap_host * host = (struct mmc_omap_host *)dev_id;
724 	u16 status;
725 	int end_command;
726 	int end_transfer;
727 	int transfer_error, cmd_error;
728 
729 	if (host->cmd == NULL && host->data == NULL) {
730 		status = OMAP_MMC_READ(host, STAT);
731 		dev_info(mmc_dev(host->slots[0]->mmc),
732 			 "Spurious IRQ 0x%04x\n", status);
733 		if (status != 0) {
734 			OMAP_MMC_WRITE(host, STAT, status);
735 			OMAP_MMC_WRITE(host, IE, 0);
736 		}
737 		return IRQ_HANDLED;
738 	}
739 
740 	end_command = 0;
741 	end_transfer = 0;
742 	transfer_error = 0;
743 	cmd_error = 0;
744 
745 	while ((status = OMAP_MMC_READ(host, STAT)) != 0) {
746 		int cmd;
747 
748 		OMAP_MMC_WRITE(host, STAT, status);
749 		if (host->cmd != NULL)
750 			cmd = host->cmd->opcode;
751 		else
752 			cmd = -1;
753 		dev_dbg(mmc_dev(host->mmc), "MMC IRQ %04x (CMD %d): ",
754 			status, cmd);
755 		mmc_omap_report_irq(host, status);
756 
757 		if (host->total_bytes_left) {
758 			if ((status & OMAP_MMC_STAT_A_FULL) ||
759 			    (status & OMAP_MMC_STAT_END_OF_DATA))
760 				mmc_omap_xfer_data(host, 0);
761 			if (status & OMAP_MMC_STAT_A_EMPTY)
762 				mmc_omap_xfer_data(host, 1);
763 		}
764 
765 		if (status & OMAP_MMC_STAT_END_OF_DATA)
766 			end_transfer = 1;
767 
768 		if (status & OMAP_MMC_STAT_DATA_TOUT) {
769 			dev_dbg(mmc_dev(host->mmc), "data timeout (CMD%d)\n",
770 				cmd);
771 			if (host->data) {
772 				host->data->error = -ETIMEDOUT;
773 				transfer_error = 1;
774 			}
775 		}
776 
777 		if (status & OMAP_MMC_STAT_DATA_CRC) {
778 			if (host->data) {
779 				host->data->error = -EILSEQ;
780 				dev_dbg(mmc_dev(host->mmc),
781 					 "data CRC error, bytes left %d\n",
782 					host->total_bytes_left);
783 				transfer_error = 1;
784 			} else {
785 				dev_dbg(mmc_dev(host->mmc), "data CRC error\n");
786 			}
787 		}
788 
789 		if (status & OMAP_MMC_STAT_CMD_TOUT) {
790 			/* Timeouts are routine with some commands */
791 			if (host->cmd) {
792 				struct mmc_omap_slot *slot =
793 					host->current_slot;
794 				if (slot == NULL ||
795 				    !mmc_omap_cover_is_open(slot))
796 					dev_err(mmc_dev(host->mmc),
797 						"command timeout (CMD%d)\n",
798 						cmd);
799 				host->cmd->error = -ETIMEDOUT;
800 				end_command = 1;
801 				cmd_error = 1;
802 			}
803 		}
804 
805 		if (status & OMAP_MMC_STAT_CMD_CRC) {
806 			if (host->cmd) {
807 				dev_err(mmc_dev(host->mmc),
808 					"command CRC error (CMD%d, arg 0x%08x)\n",
809 					cmd, host->cmd->arg);
810 				host->cmd->error = -EILSEQ;
811 				end_command = 1;
812 				cmd_error = 1;
813 			} else
814 				dev_err(mmc_dev(host->mmc),
815 					"command CRC error without cmd?\n");
816 		}
817 
818 		if (status & OMAP_MMC_STAT_CARD_ERR) {
819 			dev_dbg(mmc_dev(host->mmc),
820 				"ignoring card status error (CMD%d)\n",
821 				cmd);
822 			end_command = 1;
823 		}
824 
825 		/*
826 		 * NOTE: On 1610 the END_OF_CMD may come too early when
827 		 * starting a write
828 		 */
829 		if ((status & OMAP_MMC_STAT_END_OF_CMD) &&
830 		    (!(status & OMAP_MMC_STAT_A_EMPTY))) {
831 			end_command = 1;
832 		}
833 	}
834 
835 	if (cmd_error && host->data) {
836 		del_timer(&host->cmd_abort_timer);
837 		host->abort = 1;
838 		OMAP_MMC_WRITE(host, IE, 0);
839 		disable_irq_nosync(host->irq);
840 		queue_work(host->mmc_omap_wq, &host->cmd_abort_work);
841 		return IRQ_HANDLED;
842 	}
843 
844 	if (end_command && host->cmd)
845 		mmc_omap_cmd_done(host, host->cmd);
846 	if (host->data != NULL) {
847 		if (transfer_error)
848 			mmc_omap_xfer_done(host, host->data);
849 		else if (end_transfer)
850 			mmc_omap_end_of_data(host, host->data);
851 	}
852 
853 	return IRQ_HANDLED;
854 }
855 
856 void omap_mmc_notify_cover_event(struct device *dev, int num, int is_closed)
857 {
858 	int cover_open;
859 	struct mmc_omap_host *host = dev_get_drvdata(dev);
860 	struct mmc_omap_slot *slot = host->slots[num];
861 
862 	BUG_ON(num >= host->nr_slots);
863 
864 	/* Other subsystems can call in here before we're initialised. */
865 	if (host->nr_slots == 0 || !host->slots[num])
866 		return;
867 
868 	cover_open = mmc_omap_cover_is_open(slot);
869 	if (cover_open != slot->cover_open) {
870 		slot->cover_open = cover_open;
871 		sysfs_notify(&slot->mmc->class_dev.kobj, NULL, "cover_switch");
872 	}
873 
874 	tasklet_hi_schedule(&slot->cover_tasklet);
875 }
876 
877 static void mmc_omap_cover_timer(struct timer_list *t)
878 {
879 	struct mmc_omap_slot *slot = from_timer(slot, t, cover_timer);
880 	tasklet_schedule(&slot->cover_tasklet);
881 }
882 
883 static void mmc_omap_cover_handler(unsigned long param)
884 {
885 	struct mmc_omap_slot *slot = (struct mmc_omap_slot *)param;
886 	int cover_open = mmc_omap_cover_is_open(slot);
887 
888 	mmc_detect_change(slot->mmc, 0);
889 	if (!cover_open)
890 		return;
891 
892 	/*
893 	 * If no card is inserted, we postpone polling until
894 	 * the cover has been closed.
895 	 */
896 	if (slot->mmc->card == NULL)
897 		return;
898 
899 	mod_timer(&slot->cover_timer,
900 		  jiffies + msecs_to_jiffies(OMAP_MMC_COVER_POLL_DELAY));
901 }
902 
903 static void mmc_omap_dma_callback(void *priv)
904 {
905 	struct mmc_omap_host *host = priv;
906 	struct mmc_data *data = host->data;
907 
908 	/* If we got to the end of DMA, assume everything went well */
909 	data->bytes_xfered += data->blocks * data->blksz;
910 
911 	mmc_omap_dma_done(host, data);
912 }
913 
914 static inline void set_cmd_timeout(struct mmc_omap_host *host, struct mmc_request *req)
915 {
916 	u16 reg;
917 
918 	reg = OMAP_MMC_READ(host, SDIO);
919 	reg &= ~(1 << 5);
920 	OMAP_MMC_WRITE(host, SDIO, reg);
921 	/* Set maximum timeout */
922 	OMAP_MMC_WRITE(host, CTO, 0xff);
923 }
924 
925 static inline void set_data_timeout(struct mmc_omap_host *host, struct mmc_request *req)
926 {
927 	unsigned int timeout, cycle_ns;
928 	u16 reg;
929 
930 	cycle_ns = 1000000000 / host->current_slot->fclk_freq;
931 	timeout = req->data->timeout_ns / cycle_ns;
932 	timeout += req->data->timeout_clks;
933 
934 	/* Check if we need to use timeout multiplier register */
935 	reg = OMAP_MMC_READ(host, SDIO);
936 	if (timeout > 0xffff) {
937 		reg |= (1 << 5);
938 		timeout /= 1024;
939 	} else
940 		reg &= ~(1 << 5);
941 	OMAP_MMC_WRITE(host, SDIO, reg);
942 	OMAP_MMC_WRITE(host, DTO, timeout);
943 }
944 
945 static void
946 mmc_omap_prepare_data(struct mmc_omap_host *host, struct mmc_request *req)
947 {
948 	struct mmc_data *data = req->data;
949 	int i, use_dma = 1, block_size;
950 	struct scatterlist *sg;
951 	unsigned sg_len;
952 
953 	host->data = data;
954 	if (data == NULL) {
955 		OMAP_MMC_WRITE(host, BLEN, 0);
956 		OMAP_MMC_WRITE(host, NBLK, 0);
957 		OMAP_MMC_WRITE(host, BUF, 0);
958 		host->dma_in_use = 0;
959 		set_cmd_timeout(host, req);
960 		return;
961 	}
962 
963 	block_size = data->blksz;
964 
965 	OMAP_MMC_WRITE(host, NBLK, data->blocks - 1);
966 	OMAP_MMC_WRITE(host, BLEN, block_size - 1);
967 	set_data_timeout(host, req);
968 
969 	/* cope with calling layer confusion; it issues "single
970 	 * block" writes using multi-block scatterlists.
971 	 */
972 	sg_len = (data->blocks == 1) ? 1 : data->sg_len;
973 
974 	/* Only do DMA for entire blocks */
975 	for_each_sg(data->sg, sg, sg_len, i) {
976 		if ((sg->length % block_size) != 0) {
977 			use_dma = 0;
978 			break;
979 		}
980 	}
981 
982 	host->sg_idx = 0;
983 	if (use_dma) {
984 		enum dma_data_direction dma_data_dir;
985 		struct dma_async_tx_descriptor *tx;
986 		struct dma_chan *c;
987 		u32 burst, *bp;
988 		u16 buf;
989 
990 		/*
991 		 * FIFO is 16x2 bytes on 15xx, and 32x2 bytes on 16xx
992 		 * and 24xx. Use 16 or 32 word frames when the
993 		 * blocksize is at least that large. Blocksize is
994 		 * usually 512 bytes; but not for some SD reads.
995 		 */
996 		burst = mmc_omap15xx() ? 32 : 64;
997 		if (burst > data->blksz)
998 			burst = data->blksz;
999 
1000 		burst >>= 1;
1001 
1002 		if (data->flags & MMC_DATA_WRITE) {
1003 			c = host->dma_tx;
1004 			bp = &host->dma_tx_burst;
1005 			buf = 0x0f80 | (burst - 1) << 0;
1006 			dma_data_dir = DMA_TO_DEVICE;
1007 		} else {
1008 			c = host->dma_rx;
1009 			bp = &host->dma_rx_burst;
1010 			buf = 0x800f | (burst - 1) << 8;
1011 			dma_data_dir = DMA_FROM_DEVICE;
1012 		}
1013 
1014 		if (!c)
1015 			goto use_pio;
1016 
1017 		/* Only reconfigure if we have a different burst size */
1018 		if (*bp != burst) {
1019 			struct dma_slave_config cfg = {
1020 				.src_addr = host->phys_base +
1021 					    OMAP_MMC_REG(host, DATA),
1022 				.dst_addr = host->phys_base +
1023 					    OMAP_MMC_REG(host, DATA),
1024 				.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES,
1025 				.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES,
1026 				.src_maxburst = burst,
1027 				.dst_maxburst = burst,
1028 			};
1029 
1030 			if (dmaengine_slave_config(c, &cfg))
1031 				goto use_pio;
1032 
1033 			*bp = burst;
1034 		}
1035 
1036 		host->sg_len = dma_map_sg(c->device->dev, data->sg, sg_len,
1037 					  dma_data_dir);
1038 		if (host->sg_len == 0)
1039 			goto use_pio;
1040 
1041 		tx = dmaengine_prep_slave_sg(c, data->sg, host->sg_len,
1042 			data->flags & MMC_DATA_WRITE ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM,
1043 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1044 		if (!tx)
1045 			goto use_pio;
1046 
1047 		OMAP_MMC_WRITE(host, BUF, buf);
1048 
1049 		tx->callback = mmc_omap_dma_callback;
1050 		tx->callback_param = host;
1051 		dmaengine_submit(tx);
1052 		host->brs_received = 0;
1053 		host->dma_done = 0;
1054 		host->dma_in_use = 1;
1055 		return;
1056 	}
1057  use_pio:
1058 
1059 	/* Revert to PIO? */
1060 	OMAP_MMC_WRITE(host, BUF, 0x1f1f);
1061 	host->total_bytes_left = data->blocks * block_size;
1062 	host->sg_len = sg_len;
1063 	mmc_omap_sg_to_buf(host);
1064 	host->dma_in_use = 0;
1065 }
1066 
1067 static void mmc_omap_start_request(struct mmc_omap_host *host,
1068 				   struct mmc_request *req)
1069 {
1070 	BUG_ON(host->mrq != NULL);
1071 
1072 	host->mrq = req;
1073 
1074 	/* only touch fifo AFTER the controller readies it */
1075 	mmc_omap_prepare_data(host, req);
1076 	mmc_omap_start_command(host, req->cmd);
1077 	if (host->dma_in_use) {
1078 		struct dma_chan *c = host->data->flags & MMC_DATA_WRITE ?
1079 				host->dma_tx : host->dma_rx;
1080 
1081 		dma_async_issue_pending(c);
1082 	}
1083 }
1084 
1085 static void mmc_omap_request(struct mmc_host *mmc, struct mmc_request *req)
1086 {
1087 	struct mmc_omap_slot *slot = mmc_priv(mmc);
1088 	struct mmc_omap_host *host = slot->host;
1089 	unsigned long flags;
1090 
1091 	spin_lock_irqsave(&host->slot_lock, flags);
1092 	if (host->mmc != NULL) {
1093 		BUG_ON(slot->mrq != NULL);
1094 		slot->mrq = req;
1095 		spin_unlock_irqrestore(&host->slot_lock, flags);
1096 		return;
1097 	} else
1098 		host->mmc = mmc;
1099 	spin_unlock_irqrestore(&host->slot_lock, flags);
1100 	mmc_omap_select_slot(slot, 1);
1101 	mmc_omap_start_request(host, req);
1102 }
1103 
1104 static void mmc_omap_set_power(struct mmc_omap_slot *slot, int power_on,
1105 				int vdd)
1106 {
1107 	struct mmc_omap_host *host;
1108 
1109 	host = slot->host;
1110 
1111 	if (slot->pdata->set_power != NULL)
1112 		slot->pdata->set_power(mmc_dev(slot->mmc), slot->id, power_on,
1113 					vdd);
1114 	if (mmc_omap2()) {
1115 		u16 w;
1116 
1117 		if (power_on) {
1118 			w = OMAP_MMC_READ(host, CON);
1119 			OMAP_MMC_WRITE(host, CON, w | (1 << 11));
1120 		} else {
1121 			w = OMAP_MMC_READ(host, CON);
1122 			OMAP_MMC_WRITE(host, CON, w & ~(1 << 11));
1123 		}
1124 	}
1125 }
1126 
1127 static int mmc_omap_calc_divisor(struct mmc_host *mmc, struct mmc_ios *ios)
1128 {
1129 	struct mmc_omap_slot *slot = mmc_priv(mmc);
1130 	struct mmc_omap_host *host = slot->host;
1131 	int func_clk_rate = clk_get_rate(host->fclk);
1132 	int dsor;
1133 
1134 	if (ios->clock == 0)
1135 		return 0;
1136 
1137 	dsor = func_clk_rate / ios->clock;
1138 	if (dsor < 1)
1139 		dsor = 1;
1140 
1141 	if (func_clk_rate / dsor > ios->clock)
1142 		dsor++;
1143 
1144 	if (dsor > 250)
1145 		dsor = 250;
1146 
1147 	slot->fclk_freq = func_clk_rate / dsor;
1148 
1149 	if (ios->bus_width == MMC_BUS_WIDTH_4)
1150 		dsor |= 1 << 15;
1151 
1152 	return dsor;
1153 }
1154 
1155 static void mmc_omap_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
1156 {
1157 	struct mmc_omap_slot *slot = mmc_priv(mmc);
1158 	struct mmc_omap_host *host = slot->host;
1159 	int i, dsor;
1160 	int clk_enabled;
1161 
1162 	mmc_omap_select_slot(slot, 0);
1163 
1164 	dsor = mmc_omap_calc_divisor(mmc, ios);
1165 
1166 	if (ios->vdd != slot->vdd)
1167 		slot->vdd = ios->vdd;
1168 
1169 	clk_enabled = 0;
1170 	switch (ios->power_mode) {
1171 	case MMC_POWER_OFF:
1172 		mmc_omap_set_power(slot, 0, ios->vdd);
1173 		break;
1174 	case MMC_POWER_UP:
1175 		/* Cannot touch dsor yet, just power up MMC */
1176 		mmc_omap_set_power(slot, 1, ios->vdd);
1177 		goto exit;
1178 	case MMC_POWER_ON:
1179 		mmc_omap_fclk_enable(host, 1);
1180 		clk_enabled = 1;
1181 		dsor |= 1 << 11;
1182 		break;
1183 	}
1184 
1185 	if (slot->bus_mode != ios->bus_mode) {
1186 		if (slot->pdata->set_bus_mode != NULL)
1187 			slot->pdata->set_bus_mode(mmc_dev(mmc), slot->id,
1188 						  ios->bus_mode);
1189 		slot->bus_mode = ios->bus_mode;
1190 	}
1191 
1192 	/* On insanely high arm_per frequencies something sometimes
1193 	 * goes somehow out of sync, and the POW bit is not being set,
1194 	 * which results in the while loop below getting stuck.
1195 	 * Writing to the CON register twice seems to do the trick. */
1196 	for (i = 0; i < 2; i++)
1197 		OMAP_MMC_WRITE(host, CON, dsor);
1198 	slot->saved_con = dsor;
1199 	if (ios->power_mode == MMC_POWER_ON) {
1200 		/* worst case at 400kHz, 80 cycles makes 200 microsecs */
1201 		int usecs = 250;
1202 
1203 		/* Send clock cycles, poll completion */
1204 		OMAP_MMC_WRITE(host, IE, 0);
1205 		OMAP_MMC_WRITE(host, STAT, 0xffff);
1206 		OMAP_MMC_WRITE(host, CMD, 1 << 7);
1207 		while (usecs > 0 && (OMAP_MMC_READ(host, STAT) & 1) == 0) {
1208 			udelay(1);
1209 			usecs--;
1210 		}
1211 		OMAP_MMC_WRITE(host, STAT, 1);
1212 	}
1213 
1214 exit:
1215 	mmc_omap_release_slot(slot, clk_enabled);
1216 }
1217 
1218 static const struct mmc_host_ops mmc_omap_ops = {
1219 	.request	= mmc_omap_request,
1220 	.set_ios	= mmc_omap_set_ios,
1221 };
1222 
1223 static int mmc_omap_new_slot(struct mmc_omap_host *host, int id)
1224 {
1225 	struct mmc_omap_slot *slot = NULL;
1226 	struct mmc_host *mmc;
1227 	int r;
1228 
1229 	mmc = mmc_alloc_host(sizeof(struct mmc_omap_slot), host->dev);
1230 	if (mmc == NULL)
1231 		return -ENOMEM;
1232 
1233 	slot = mmc_priv(mmc);
1234 	slot->host = host;
1235 	slot->mmc = mmc;
1236 	slot->id = id;
1237 	slot->pdata = &host->pdata->slots[id];
1238 
1239 	host->slots[id] = slot;
1240 
1241 	mmc->caps = 0;
1242 	if (host->pdata->slots[id].wires >= 4)
1243 		mmc->caps |= MMC_CAP_4_BIT_DATA | MMC_CAP_ERASE;
1244 
1245 	mmc->ops = &mmc_omap_ops;
1246 	mmc->f_min = 400000;
1247 
1248 	if (mmc_omap2())
1249 		mmc->f_max = 48000000;
1250 	else
1251 		mmc->f_max = 24000000;
1252 	if (host->pdata->max_freq)
1253 		mmc->f_max = min(host->pdata->max_freq, mmc->f_max);
1254 	mmc->ocr_avail = slot->pdata->ocr_mask;
1255 
1256 	/* Use scatterlist DMA to reduce per-transfer costs.
1257 	 * NOTE max_seg_size assumption that small blocks aren't
1258 	 * normally used (except e.g. for reading SD registers).
1259 	 */
1260 	mmc->max_segs = 32;
1261 	mmc->max_blk_size = 2048;	/* BLEN is 11 bits (+1) */
1262 	mmc->max_blk_count = 2048;	/* NBLK is 11 bits (+1) */
1263 	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
1264 	mmc->max_seg_size = mmc->max_req_size;
1265 
1266 	if (slot->pdata->get_cover_state != NULL) {
1267 		timer_setup(&slot->cover_timer, mmc_omap_cover_timer, 0);
1268 		tasklet_init(&slot->cover_tasklet, mmc_omap_cover_handler,
1269 			     (unsigned long)slot);
1270 	}
1271 
1272 	r = mmc_add_host(mmc);
1273 	if (r < 0)
1274 		goto err_remove_host;
1275 
1276 	if (slot->pdata->name != NULL) {
1277 		r = device_create_file(&mmc->class_dev,
1278 					&dev_attr_slot_name);
1279 		if (r < 0)
1280 			goto err_remove_host;
1281 	}
1282 
1283 	if (slot->pdata->get_cover_state != NULL) {
1284 		r = device_create_file(&mmc->class_dev,
1285 					&dev_attr_cover_switch);
1286 		if (r < 0)
1287 			goto err_remove_slot_name;
1288 		tasklet_schedule(&slot->cover_tasklet);
1289 	}
1290 
1291 	return 0;
1292 
1293 err_remove_slot_name:
1294 	if (slot->pdata->name != NULL)
1295 		device_remove_file(&mmc->class_dev, &dev_attr_slot_name);
1296 err_remove_host:
1297 	mmc_remove_host(mmc);
1298 	mmc_free_host(mmc);
1299 	return r;
1300 }
1301 
1302 static void mmc_omap_remove_slot(struct mmc_omap_slot *slot)
1303 {
1304 	struct mmc_host *mmc = slot->mmc;
1305 
1306 	if (slot->pdata->name != NULL)
1307 		device_remove_file(&mmc->class_dev, &dev_attr_slot_name);
1308 	if (slot->pdata->get_cover_state != NULL)
1309 		device_remove_file(&mmc->class_dev, &dev_attr_cover_switch);
1310 
1311 	tasklet_kill(&slot->cover_tasklet);
1312 	del_timer_sync(&slot->cover_timer);
1313 	flush_workqueue(slot->host->mmc_omap_wq);
1314 
1315 	mmc_remove_host(mmc);
1316 	mmc_free_host(mmc);
1317 }
1318 
1319 static int mmc_omap_probe(struct platform_device *pdev)
1320 {
1321 	struct omap_mmc_platform_data *pdata = pdev->dev.platform_data;
1322 	struct mmc_omap_host *host = NULL;
1323 	struct resource *res;
1324 	int i, ret = 0;
1325 	int irq;
1326 
1327 	if (pdata == NULL) {
1328 		dev_err(&pdev->dev, "platform data missing\n");
1329 		return -ENXIO;
1330 	}
1331 	if (pdata->nr_slots == 0) {
1332 		dev_err(&pdev->dev, "no slots\n");
1333 		return -EPROBE_DEFER;
1334 	}
1335 
1336 	host = devm_kzalloc(&pdev->dev, sizeof(struct mmc_omap_host),
1337 			    GFP_KERNEL);
1338 	if (host == NULL)
1339 		return -ENOMEM;
1340 
1341 	irq = platform_get_irq(pdev, 0);
1342 	if (irq < 0)
1343 		return -ENXIO;
1344 
1345 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1346 	host->virt_base = devm_ioremap_resource(&pdev->dev, res);
1347 	if (IS_ERR(host->virt_base))
1348 		return PTR_ERR(host->virt_base);
1349 
1350 	INIT_WORK(&host->slot_release_work, mmc_omap_slot_release_work);
1351 	INIT_WORK(&host->send_stop_work, mmc_omap_send_stop_work);
1352 
1353 	INIT_WORK(&host->cmd_abort_work, mmc_omap_abort_command);
1354 	timer_setup(&host->cmd_abort_timer, mmc_omap_cmd_timer, 0);
1355 
1356 	spin_lock_init(&host->clk_lock);
1357 	timer_setup(&host->clk_timer, mmc_omap_clk_timer, 0);
1358 
1359 	spin_lock_init(&host->dma_lock);
1360 	spin_lock_init(&host->slot_lock);
1361 	init_waitqueue_head(&host->slot_wq);
1362 
1363 	host->pdata = pdata;
1364 	host->features = host->pdata->slots[0].features;
1365 	host->dev = &pdev->dev;
1366 	platform_set_drvdata(pdev, host);
1367 
1368 	host->id = pdev->id;
1369 	host->irq = irq;
1370 	host->phys_base = res->start;
1371 	host->iclk = clk_get(&pdev->dev, "ick");
1372 	if (IS_ERR(host->iclk))
1373 		return PTR_ERR(host->iclk);
1374 	clk_enable(host->iclk);
1375 
1376 	host->fclk = clk_get(&pdev->dev, "fck");
1377 	if (IS_ERR(host->fclk)) {
1378 		ret = PTR_ERR(host->fclk);
1379 		goto err_free_iclk;
1380 	}
1381 
1382 	host->dma_tx_burst = -1;
1383 	host->dma_rx_burst = -1;
1384 
1385 	host->dma_tx = dma_request_chan(&pdev->dev, "tx");
1386 	if (IS_ERR(host->dma_tx)) {
1387 		ret = PTR_ERR(host->dma_tx);
1388 		if (ret == -EPROBE_DEFER) {
1389 			clk_put(host->fclk);
1390 			goto err_free_iclk;
1391 		}
1392 
1393 		host->dma_tx = NULL;
1394 		dev_warn(host->dev, "TX DMA channel request failed\n");
1395 	}
1396 
1397 	host->dma_rx = dma_request_chan(&pdev->dev, "rx");
1398 	if (IS_ERR(host->dma_rx)) {
1399 		ret = PTR_ERR(host->dma_rx);
1400 		if (ret == -EPROBE_DEFER) {
1401 			if (host->dma_tx)
1402 				dma_release_channel(host->dma_tx);
1403 			clk_put(host->fclk);
1404 			goto err_free_iclk;
1405 		}
1406 
1407 		host->dma_rx = NULL;
1408 		dev_warn(host->dev, "RX DMA channel request failed\n");
1409 	}
1410 
1411 	ret = request_irq(host->irq, mmc_omap_irq, 0, DRIVER_NAME, host);
1412 	if (ret)
1413 		goto err_free_dma;
1414 
1415 	if (pdata->init != NULL) {
1416 		ret = pdata->init(&pdev->dev);
1417 		if (ret < 0)
1418 			goto err_free_irq;
1419 	}
1420 
1421 	host->nr_slots = pdata->nr_slots;
1422 	host->reg_shift = (mmc_omap7xx() ? 1 : 2);
1423 
1424 	host->mmc_omap_wq = alloc_workqueue("mmc_omap", 0, 0);
1425 	if (!host->mmc_omap_wq) {
1426 		ret = -ENOMEM;
1427 		goto err_plat_cleanup;
1428 	}
1429 
1430 	for (i = 0; i < pdata->nr_slots; i++) {
1431 		ret = mmc_omap_new_slot(host, i);
1432 		if (ret < 0) {
1433 			while (--i >= 0)
1434 				mmc_omap_remove_slot(host->slots[i]);
1435 
1436 			goto err_destroy_wq;
1437 		}
1438 	}
1439 
1440 	return 0;
1441 
1442 err_destroy_wq:
1443 	destroy_workqueue(host->mmc_omap_wq);
1444 err_plat_cleanup:
1445 	if (pdata->cleanup)
1446 		pdata->cleanup(&pdev->dev);
1447 err_free_irq:
1448 	free_irq(host->irq, host);
1449 err_free_dma:
1450 	if (host->dma_tx)
1451 		dma_release_channel(host->dma_tx);
1452 	if (host->dma_rx)
1453 		dma_release_channel(host->dma_rx);
1454 	clk_put(host->fclk);
1455 err_free_iclk:
1456 	clk_disable(host->iclk);
1457 	clk_put(host->iclk);
1458 	return ret;
1459 }
1460 
1461 static int mmc_omap_remove(struct platform_device *pdev)
1462 {
1463 	struct mmc_omap_host *host = platform_get_drvdata(pdev);
1464 	int i;
1465 
1466 	BUG_ON(host == NULL);
1467 
1468 	for (i = 0; i < host->nr_slots; i++)
1469 		mmc_omap_remove_slot(host->slots[i]);
1470 
1471 	if (host->pdata->cleanup)
1472 		host->pdata->cleanup(&pdev->dev);
1473 
1474 	mmc_omap_fclk_enable(host, 0);
1475 	free_irq(host->irq, host);
1476 	clk_put(host->fclk);
1477 	clk_disable(host->iclk);
1478 	clk_put(host->iclk);
1479 
1480 	if (host->dma_tx)
1481 		dma_release_channel(host->dma_tx);
1482 	if (host->dma_rx)
1483 		dma_release_channel(host->dma_rx);
1484 
1485 	destroy_workqueue(host->mmc_omap_wq);
1486 
1487 	return 0;
1488 }
1489 
1490 #if IS_BUILTIN(CONFIG_OF)
1491 static const struct of_device_id mmc_omap_match[] = {
1492 	{ .compatible = "ti,omap2420-mmc", },
1493 	{ },
1494 };
1495 MODULE_DEVICE_TABLE(of, mmc_omap_match);
1496 #endif
1497 
1498 static struct platform_driver mmc_omap_driver = {
1499 	.probe		= mmc_omap_probe,
1500 	.remove		= mmc_omap_remove,
1501 	.driver		= {
1502 		.name	= DRIVER_NAME,
1503 		.of_match_table = of_match_ptr(mmc_omap_match),
1504 	},
1505 };
1506 
1507 module_platform_driver(mmc_omap_driver);
1508 MODULE_DESCRIPTION("OMAP Multimedia Card driver");
1509 MODULE_LICENSE("GPL");
1510 MODULE_ALIAS("platform:" DRIVER_NAME);
1511 MODULE_AUTHOR("Juha Yrjölä");
1512