xref: /openbmc/linux/drivers/mmc/host/omap.c (revision 63705da3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/drivers/mmc/host/omap.c
4  *
5  *  Copyright (C) 2004 Nokia Corporation
6  *  Written by Tuukka Tikkanen and Juha Yrjölä<juha.yrjola@nokia.com>
7  *  Misc hacks here and there by Tony Lindgren <tony@atomide.com>
8  *  Other hacks (DMA, SD, etc) by David Brownell
9  */
10 
11 #include <linux/module.h>
12 #include <linux/moduleparam.h>
13 #include <linux/init.h>
14 #include <linux/ioport.h>
15 #include <linux/platform_device.h>
16 #include <linux/interrupt.h>
17 #include <linux/dmaengine.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/delay.h>
20 #include <linux/spinlock.h>
21 #include <linux/timer.h>
22 #include <linux/of.h>
23 #include <linux/mmc/host.h>
24 #include <linux/mmc/card.h>
25 #include <linux/mmc/mmc.h>
26 #include <linux/clk.h>
27 #include <linux/scatterlist.h>
28 #include <linux/slab.h>
29 #include <linux/platform_data/mmc-omap.h>
30 
31 
32 #define	OMAP_MMC_REG_CMD	0x00
33 #define	OMAP_MMC_REG_ARGL	0x01
34 #define	OMAP_MMC_REG_ARGH	0x02
35 #define	OMAP_MMC_REG_CON	0x03
36 #define	OMAP_MMC_REG_STAT	0x04
37 #define	OMAP_MMC_REG_IE		0x05
38 #define	OMAP_MMC_REG_CTO	0x06
39 #define	OMAP_MMC_REG_DTO	0x07
40 #define	OMAP_MMC_REG_DATA	0x08
41 #define	OMAP_MMC_REG_BLEN	0x09
42 #define	OMAP_MMC_REG_NBLK	0x0a
43 #define	OMAP_MMC_REG_BUF	0x0b
44 #define	OMAP_MMC_REG_SDIO	0x0d
45 #define	OMAP_MMC_REG_REV	0x0f
46 #define	OMAP_MMC_REG_RSP0	0x10
47 #define	OMAP_MMC_REG_RSP1	0x11
48 #define	OMAP_MMC_REG_RSP2	0x12
49 #define	OMAP_MMC_REG_RSP3	0x13
50 #define	OMAP_MMC_REG_RSP4	0x14
51 #define	OMAP_MMC_REG_RSP5	0x15
52 #define	OMAP_MMC_REG_RSP6	0x16
53 #define	OMAP_MMC_REG_RSP7	0x17
54 #define	OMAP_MMC_REG_IOSR	0x18
55 #define	OMAP_MMC_REG_SYSC	0x19
56 #define	OMAP_MMC_REG_SYSS	0x1a
57 
58 #define	OMAP_MMC_STAT_CARD_ERR		(1 << 14)
59 #define	OMAP_MMC_STAT_CARD_IRQ		(1 << 13)
60 #define	OMAP_MMC_STAT_OCR_BUSY		(1 << 12)
61 #define	OMAP_MMC_STAT_A_EMPTY		(1 << 11)
62 #define	OMAP_MMC_STAT_A_FULL		(1 << 10)
63 #define	OMAP_MMC_STAT_CMD_CRC		(1 <<  8)
64 #define	OMAP_MMC_STAT_CMD_TOUT		(1 <<  7)
65 #define	OMAP_MMC_STAT_DATA_CRC		(1 <<  6)
66 #define	OMAP_MMC_STAT_DATA_TOUT		(1 <<  5)
67 #define	OMAP_MMC_STAT_END_BUSY		(1 <<  4)
68 #define	OMAP_MMC_STAT_END_OF_DATA	(1 <<  3)
69 #define	OMAP_MMC_STAT_CARD_BUSY		(1 <<  2)
70 #define	OMAP_MMC_STAT_END_OF_CMD	(1 <<  0)
71 
72 #define mmc_omap7xx()	(host->features & MMC_OMAP7XX)
73 #define mmc_omap15xx()	(host->features & MMC_OMAP15XX)
74 #define mmc_omap16xx()	(host->features & MMC_OMAP16XX)
75 #define MMC_OMAP1_MASK	(MMC_OMAP7XX | MMC_OMAP15XX | MMC_OMAP16XX)
76 #define mmc_omap1()	(host->features & MMC_OMAP1_MASK)
77 #define mmc_omap2()	(!mmc_omap1())
78 
79 #define OMAP_MMC_REG(host, reg)		(OMAP_MMC_REG_##reg << (host)->reg_shift)
80 #define OMAP_MMC_READ(host, reg)	__raw_readw((host)->virt_base + OMAP_MMC_REG(host, reg))
81 #define OMAP_MMC_WRITE(host, reg, val)	__raw_writew((val), (host)->virt_base + OMAP_MMC_REG(host, reg))
82 
83 /*
84  * Command types
85  */
86 #define OMAP_MMC_CMDTYPE_BC	0
87 #define OMAP_MMC_CMDTYPE_BCR	1
88 #define OMAP_MMC_CMDTYPE_AC	2
89 #define OMAP_MMC_CMDTYPE_ADTC	3
90 
91 #define DRIVER_NAME "mmci-omap"
92 
93 /* Specifies how often in millisecs to poll for card status changes
94  * when the cover switch is open */
95 #define OMAP_MMC_COVER_POLL_DELAY	500
96 
97 struct mmc_omap_host;
98 
99 struct mmc_omap_slot {
100 	int			id;
101 	unsigned int		vdd;
102 	u16			saved_con;
103 	u16			bus_mode;
104 	u16			power_mode;
105 	unsigned int		fclk_freq;
106 
107 	struct tasklet_struct	cover_tasklet;
108 	struct timer_list       cover_timer;
109 	unsigned		cover_open;
110 
111 	struct mmc_request      *mrq;
112 	struct mmc_omap_host    *host;
113 	struct mmc_host		*mmc;
114 	struct omap_mmc_slot_data *pdata;
115 };
116 
117 struct mmc_omap_host {
118 	int			initialized;
119 	struct mmc_request *	mrq;
120 	struct mmc_command *	cmd;
121 	struct mmc_data *	data;
122 	struct mmc_host *	mmc;
123 	struct device *		dev;
124 	unsigned char		id; /* 16xx chips have 2 MMC blocks */
125 	struct clk *		iclk;
126 	struct clk *		fclk;
127 	struct dma_chan		*dma_rx;
128 	u32			dma_rx_burst;
129 	struct dma_chan		*dma_tx;
130 	u32			dma_tx_burst;
131 	void __iomem		*virt_base;
132 	unsigned int		phys_base;
133 	int			irq;
134 	unsigned char		bus_mode;
135 	unsigned int		reg_shift;
136 
137 	struct work_struct	cmd_abort_work;
138 	unsigned		abort:1;
139 	struct timer_list	cmd_abort_timer;
140 
141 	struct work_struct      slot_release_work;
142 	struct mmc_omap_slot    *next_slot;
143 	struct work_struct      send_stop_work;
144 	struct mmc_data		*stop_data;
145 
146 	unsigned int		sg_len;
147 	int			sg_idx;
148 	u16 *			buffer;
149 	u32			buffer_bytes_left;
150 	u32			total_bytes_left;
151 
152 	unsigned		features;
153 	unsigned		brs_received:1, dma_done:1;
154 	unsigned		dma_in_use:1;
155 	spinlock_t		dma_lock;
156 
157 	struct mmc_omap_slot    *slots[OMAP_MMC_MAX_SLOTS];
158 	struct mmc_omap_slot    *current_slot;
159 	spinlock_t              slot_lock;
160 	wait_queue_head_t       slot_wq;
161 	int                     nr_slots;
162 
163 	struct timer_list       clk_timer;
164 	spinlock_t		clk_lock;     /* for changing enabled state */
165 	unsigned int            fclk_enabled:1;
166 	struct workqueue_struct *mmc_omap_wq;
167 
168 	struct omap_mmc_platform_data *pdata;
169 };
170 
171 
172 static void mmc_omap_fclk_offdelay(struct mmc_omap_slot *slot)
173 {
174 	unsigned long tick_ns;
175 
176 	if (slot != NULL && slot->host->fclk_enabled && slot->fclk_freq > 0) {
177 		tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, slot->fclk_freq);
178 		ndelay(8 * tick_ns);
179 	}
180 }
181 
182 static void mmc_omap_fclk_enable(struct mmc_omap_host *host, unsigned int enable)
183 {
184 	unsigned long flags;
185 
186 	spin_lock_irqsave(&host->clk_lock, flags);
187 	if (host->fclk_enabled != enable) {
188 		host->fclk_enabled = enable;
189 		if (enable)
190 			clk_enable(host->fclk);
191 		else
192 			clk_disable(host->fclk);
193 	}
194 	spin_unlock_irqrestore(&host->clk_lock, flags);
195 }
196 
197 static void mmc_omap_select_slot(struct mmc_omap_slot *slot, int claimed)
198 {
199 	struct mmc_omap_host *host = slot->host;
200 	unsigned long flags;
201 
202 	if (claimed)
203 		goto no_claim;
204 	spin_lock_irqsave(&host->slot_lock, flags);
205 	while (host->mmc != NULL) {
206 		spin_unlock_irqrestore(&host->slot_lock, flags);
207 		wait_event(host->slot_wq, host->mmc == NULL);
208 		spin_lock_irqsave(&host->slot_lock, flags);
209 	}
210 	host->mmc = slot->mmc;
211 	spin_unlock_irqrestore(&host->slot_lock, flags);
212 no_claim:
213 	del_timer(&host->clk_timer);
214 	if (host->current_slot != slot || !claimed)
215 		mmc_omap_fclk_offdelay(host->current_slot);
216 
217 	if (host->current_slot != slot) {
218 		OMAP_MMC_WRITE(host, CON, slot->saved_con & 0xFC00);
219 		if (host->pdata->switch_slot != NULL)
220 			host->pdata->switch_slot(mmc_dev(slot->mmc), slot->id);
221 		host->current_slot = slot;
222 	}
223 
224 	if (claimed) {
225 		mmc_omap_fclk_enable(host, 1);
226 
227 		/* Doing the dummy read here seems to work around some bug
228 		 * at least in OMAP24xx silicon where the command would not
229 		 * start after writing the CMD register. Sigh. */
230 		OMAP_MMC_READ(host, CON);
231 
232 		OMAP_MMC_WRITE(host, CON, slot->saved_con);
233 	} else
234 		mmc_omap_fclk_enable(host, 0);
235 }
236 
237 static void mmc_omap_start_request(struct mmc_omap_host *host,
238 				   struct mmc_request *req);
239 
240 static void mmc_omap_slot_release_work(struct work_struct *work)
241 {
242 	struct mmc_omap_host *host = container_of(work, struct mmc_omap_host,
243 						  slot_release_work);
244 	struct mmc_omap_slot *next_slot = host->next_slot;
245 	struct mmc_request *rq;
246 
247 	host->next_slot = NULL;
248 	mmc_omap_select_slot(next_slot, 1);
249 
250 	rq = next_slot->mrq;
251 	next_slot->mrq = NULL;
252 	mmc_omap_start_request(host, rq);
253 }
254 
255 static void mmc_omap_release_slot(struct mmc_omap_slot *slot, int clk_enabled)
256 {
257 	struct mmc_omap_host *host = slot->host;
258 	unsigned long flags;
259 	int i;
260 
261 	BUG_ON(slot == NULL || host->mmc == NULL);
262 
263 	if (clk_enabled)
264 		/* Keeps clock running for at least 8 cycles on valid freq */
265 		mod_timer(&host->clk_timer, jiffies  + HZ/10);
266 	else {
267 		del_timer(&host->clk_timer);
268 		mmc_omap_fclk_offdelay(slot);
269 		mmc_omap_fclk_enable(host, 0);
270 	}
271 
272 	spin_lock_irqsave(&host->slot_lock, flags);
273 	/* Check for any pending requests */
274 	for (i = 0; i < host->nr_slots; i++) {
275 		struct mmc_omap_slot *new_slot;
276 
277 		if (host->slots[i] == NULL || host->slots[i]->mrq == NULL)
278 			continue;
279 
280 		BUG_ON(host->next_slot != NULL);
281 		new_slot = host->slots[i];
282 		/* The current slot should not have a request in queue */
283 		BUG_ON(new_slot == host->current_slot);
284 
285 		host->next_slot = new_slot;
286 		host->mmc = new_slot->mmc;
287 		spin_unlock_irqrestore(&host->slot_lock, flags);
288 		queue_work(host->mmc_omap_wq, &host->slot_release_work);
289 		return;
290 	}
291 
292 	host->mmc = NULL;
293 	wake_up(&host->slot_wq);
294 	spin_unlock_irqrestore(&host->slot_lock, flags);
295 }
296 
297 static inline
298 int mmc_omap_cover_is_open(struct mmc_omap_slot *slot)
299 {
300 	if (slot->pdata->get_cover_state)
301 		return slot->pdata->get_cover_state(mmc_dev(slot->mmc),
302 						    slot->id);
303 	return 0;
304 }
305 
306 static ssize_t
307 mmc_omap_show_cover_switch(struct device *dev, struct device_attribute *attr,
308 			   char *buf)
309 {
310 	struct mmc_host *mmc = container_of(dev, struct mmc_host, class_dev);
311 	struct mmc_omap_slot *slot = mmc_priv(mmc);
312 
313 	return sprintf(buf, "%s\n", mmc_omap_cover_is_open(slot) ? "open" :
314 		       "closed");
315 }
316 
317 static DEVICE_ATTR(cover_switch, S_IRUGO, mmc_omap_show_cover_switch, NULL);
318 
319 static ssize_t
320 mmc_omap_show_slot_name(struct device *dev, struct device_attribute *attr,
321 			char *buf)
322 {
323 	struct mmc_host *mmc = container_of(dev, struct mmc_host, class_dev);
324 	struct mmc_omap_slot *slot = mmc_priv(mmc);
325 
326 	return sprintf(buf, "%s\n", slot->pdata->name);
327 }
328 
329 static DEVICE_ATTR(slot_name, S_IRUGO, mmc_omap_show_slot_name, NULL);
330 
331 static void
332 mmc_omap_start_command(struct mmc_omap_host *host, struct mmc_command *cmd)
333 {
334 	u32 cmdreg;
335 	u32 resptype;
336 	u32 cmdtype;
337 	u16 irq_mask;
338 
339 	host->cmd = cmd;
340 
341 	resptype = 0;
342 	cmdtype = 0;
343 
344 	/* Our hardware needs to know exact type */
345 	switch (mmc_resp_type(cmd)) {
346 	case MMC_RSP_NONE:
347 		break;
348 	case MMC_RSP_R1:
349 	case MMC_RSP_R1B:
350 		/* resp 1, 1b, 6, 7 */
351 		resptype = 1;
352 		break;
353 	case MMC_RSP_R2:
354 		resptype = 2;
355 		break;
356 	case MMC_RSP_R3:
357 		resptype = 3;
358 		break;
359 	default:
360 		dev_err(mmc_dev(host->mmc), "Invalid response type: %04x\n", mmc_resp_type(cmd));
361 		break;
362 	}
363 
364 	if (mmc_cmd_type(cmd) == MMC_CMD_ADTC) {
365 		cmdtype = OMAP_MMC_CMDTYPE_ADTC;
366 	} else if (mmc_cmd_type(cmd) == MMC_CMD_BC) {
367 		cmdtype = OMAP_MMC_CMDTYPE_BC;
368 	} else if (mmc_cmd_type(cmd) == MMC_CMD_BCR) {
369 		cmdtype = OMAP_MMC_CMDTYPE_BCR;
370 	} else {
371 		cmdtype = OMAP_MMC_CMDTYPE_AC;
372 	}
373 
374 	cmdreg = cmd->opcode | (resptype << 8) | (cmdtype << 12);
375 
376 	if (host->current_slot->bus_mode == MMC_BUSMODE_OPENDRAIN)
377 		cmdreg |= 1 << 6;
378 
379 	if (cmd->flags & MMC_RSP_BUSY)
380 		cmdreg |= 1 << 11;
381 
382 	if (host->data && !(host->data->flags & MMC_DATA_WRITE))
383 		cmdreg |= 1 << 15;
384 
385 	mod_timer(&host->cmd_abort_timer, jiffies + HZ/2);
386 
387 	OMAP_MMC_WRITE(host, CTO, 200);
388 	OMAP_MMC_WRITE(host, ARGL, cmd->arg & 0xffff);
389 	OMAP_MMC_WRITE(host, ARGH, cmd->arg >> 16);
390 	irq_mask = OMAP_MMC_STAT_A_EMPTY    | OMAP_MMC_STAT_A_FULL    |
391 		   OMAP_MMC_STAT_CMD_CRC    | OMAP_MMC_STAT_CMD_TOUT  |
392 		   OMAP_MMC_STAT_DATA_CRC   | OMAP_MMC_STAT_DATA_TOUT |
393 		   OMAP_MMC_STAT_END_OF_CMD | OMAP_MMC_STAT_CARD_ERR  |
394 		   OMAP_MMC_STAT_END_OF_DATA;
395 	if (cmd->opcode == MMC_ERASE)
396 		irq_mask &= ~OMAP_MMC_STAT_DATA_TOUT;
397 	OMAP_MMC_WRITE(host, IE, irq_mask);
398 	OMAP_MMC_WRITE(host, CMD, cmdreg);
399 }
400 
401 static void
402 mmc_omap_release_dma(struct mmc_omap_host *host, struct mmc_data *data,
403 		     int abort)
404 {
405 	enum dma_data_direction dma_data_dir;
406 	struct device *dev = mmc_dev(host->mmc);
407 	struct dma_chan *c;
408 
409 	if (data->flags & MMC_DATA_WRITE) {
410 		dma_data_dir = DMA_TO_DEVICE;
411 		c = host->dma_tx;
412 	} else {
413 		dma_data_dir = DMA_FROM_DEVICE;
414 		c = host->dma_rx;
415 	}
416 	if (c) {
417 		if (data->error) {
418 			dmaengine_terminate_all(c);
419 			/* Claim nothing transferred on error... */
420 			data->bytes_xfered = 0;
421 		}
422 		dev = c->device->dev;
423 	}
424 	dma_unmap_sg(dev, data->sg, host->sg_len, dma_data_dir);
425 }
426 
427 static void mmc_omap_send_stop_work(struct work_struct *work)
428 {
429 	struct mmc_omap_host *host = container_of(work, struct mmc_omap_host,
430 						  send_stop_work);
431 	struct mmc_omap_slot *slot = host->current_slot;
432 	struct mmc_data *data = host->stop_data;
433 	unsigned long tick_ns;
434 
435 	tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, slot->fclk_freq);
436 	ndelay(8*tick_ns);
437 
438 	mmc_omap_start_command(host, data->stop);
439 }
440 
441 static void
442 mmc_omap_xfer_done(struct mmc_omap_host *host, struct mmc_data *data)
443 {
444 	if (host->dma_in_use)
445 		mmc_omap_release_dma(host, data, data->error);
446 
447 	host->data = NULL;
448 	host->sg_len = 0;
449 
450 	/* NOTE:  MMC layer will sometimes poll-wait CMD13 next, issuing
451 	 * dozens of requests until the card finishes writing data.
452 	 * It'd be cheaper to just wait till an EOFB interrupt arrives...
453 	 */
454 
455 	if (!data->stop) {
456 		struct mmc_host *mmc;
457 
458 		host->mrq = NULL;
459 		mmc = host->mmc;
460 		mmc_omap_release_slot(host->current_slot, 1);
461 		mmc_request_done(mmc, data->mrq);
462 		return;
463 	}
464 
465 	host->stop_data = data;
466 	queue_work(host->mmc_omap_wq, &host->send_stop_work);
467 }
468 
469 static void
470 mmc_omap_send_abort(struct mmc_omap_host *host, int maxloops)
471 {
472 	struct mmc_omap_slot *slot = host->current_slot;
473 	unsigned int restarts, passes, timeout;
474 	u16 stat = 0;
475 
476 	/* Sending abort takes 80 clocks. Have some extra and round up */
477 	timeout = DIV_ROUND_UP(120 * USEC_PER_SEC, slot->fclk_freq);
478 	restarts = 0;
479 	while (restarts < maxloops) {
480 		OMAP_MMC_WRITE(host, STAT, 0xFFFF);
481 		OMAP_MMC_WRITE(host, CMD, (3 << 12) | (1 << 7));
482 
483 		passes = 0;
484 		while (passes < timeout) {
485 			stat = OMAP_MMC_READ(host, STAT);
486 			if (stat & OMAP_MMC_STAT_END_OF_CMD)
487 				goto out;
488 			udelay(1);
489 			passes++;
490 		}
491 
492 		restarts++;
493 	}
494 out:
495 	OMAP_MMC_WRITE(host, STAT, stat);
496 }
497 
498 static void
499 mmc_omap_abort_xfer(struct mmc_omap_host *host, struct mmc_data *data)
500 {
501 	if (host->dma_in_use)
502 		mmc_omap_release_dma(host, data, 1);
503 
504 	host->data = NULL;
505 	host->sg_len = 0;
506 
507 	mmc_omap_send_abort(host, 10000);
508 }
509 
510 static void
511 mmc_omap_end_of_data(struct mmc_omap_host *host, struct mmc_data *data)
512 {
513 	unsigned long flags;
514 	int done;
515 
516 	if (!host->dma_in_use) {
517 		mmc_omap_xfer_done(host, data);
518 		return;
519 	}
520 	done = 0;
521 	spin_lock_irqsave(&host->dma_lock, flags);
522 	if (host->dma_done)
523 		done = 1;
524 	else
525 		host->brs_received = 1;
526 	spin_unlock_irqrestore(&host->dma_lock, flags);
527 	if (done)
528 		mmc_omap_xfer_done(host, data);
529 }
530 
531 static void
532 mmc_omap_dma_done(struct mmc_omap_host *host, struct mmc_data *data)
533 {
534 	unsigned long flags;
535 	int done;
536 
537 	done = 0;
538 	spin_lock_irqsave(&host->dma_lock, flags);
539 	if (host->brs_received)
540 		done = 1;
541 	else
542 		host->dma_done = 1;
543 	spin_unlock_irqrestore(&host->dma_lock, flags);
544 	if (done)
545 		mmc_omap_xfer_done(host, data);
546 }
547 
548 static void
549 mmc_omap_cmd_done(struct mmc_omap_host *host, struct mmc_command *cmd)
550 {
551 	host->cmd = NULL;
552 
553 	del_timer(&host->cmd_abort_timer);
554 
555 	if (cmd->flags & MMC_RSP_PRESENT) {
556 		if (cmd->flags & MMC_RSP_136) {
557 			/* response type 2 */
558 			cmd->resp[3] =
559 				OMAP_MMC_READ(host, RSP0) |
560 				(OMAP_MMC_READ(host, RSP1) << 16);
561 			cmd->resp[2] =
562 				OMAP_MMC_READ(host, RSP2) |
563 				(OMAP_MMC_READ(host, RSP3) << 16);
564 			cmd->resp[1] =
565 				OMAP_MMC_READ(host, RSP4) |
566 				(OMAP_MMC_READ(host, RSP5) << 16);
567 			cmd->resp[0] =
568 				OMAP_MMC_READ(host, RSP6) |
569 				(OMAP_MMC_READ(host, RSP7) << 16);
570 		} else {
571 			/* response types 1, 1b, 3, 4, 5, 6 */
572 			cmd->resp[0] =
573 				OMAP_MMC_READ(host, RSP6) |
574 				(OMAP_MMC_READ(host, RSP7) << 16);
575 		}
576 	}
577 
578 	if (host->data == NULL || cmd->error) {
579 		struct mmc_host *mmc;
580 
581 		if (host->data != NULL)
582 			mmc_omap_abort_xfer(host, host->data);
583 		host->mrq = NULL;
584 		mmc = host->mmc;
585 		mmc_omap_release_slot(host->current_slot, 1);
586 		mmc_request_done(mmc, cmd->mrq);
587 	}
588 }
589 
590 /*
591  * Abort stuck command. Can occur when card is removed while it is being
592  * read.
593  */
594 static void mmc_omap_abort_command(struct work_struct *work)
595 {
596 	struct mmc_omap_host *host = container_of(work, struct mmc_omap_host,
597 						  cmd_abort_work);
598 	BUG_ON(!host->cmd);
599 
600 	dev_dbg(mmc_dev(host->mmc), "Aborting stuck command CMD%d\n",
601 		host->cmd->opcode);
602 
603 	if (host->cmd->error == 0)
604 		host->cmd->error = -ETIMEDOUT;
605 
606 	if (host->data == NULL) {
607 		struct mmc_command *cmd;
608 		struct mmc_host    *mmc;
609 
610 		cmd = host->cmd;
611 		host->cmd = NULL;
612 		mmc_omap_send_abort(host, 10000);
613 
614 		host->mrq = NULL;
615 		mmc = host->mmc;
616 		mmc_omap_release_slot(host->current_slot, 1);
617 		mmc_request_done(mmc, cmd->mrq);
618 	} else
619 		mmc_omap_cmd_done(host, host->cmd);
620 
621 	host->abort = 0;
622 	enable_irq(host->irq);
623 }
624 
625 static void
626 mmc_omap_cmd_timer(struct timer_list *t)
627 {
628 	struct mmc_omap_host *host = from_timer(host, t, cmd_abort_timer);
629 	unsigned long flags;
630 
631 	spin_lock_irqsave(&host->slot_lock, flags);
632 	if (host->cmd != NULL && !host->abort) {
633 		OMAP_MMC_WRITE(host, IE, 0);
634 		disable_irq(host->irq);
635 		host->abort = 1;
636 		queue_work(host->mmc_omap_wq, &host->cmd_abort_work);
637 	}
638 	spin_unlock_irqrestore(&host->slot_lock, flags);
639 }
640 
641 /* PIO only */
642 static void
643 mmc_omap_sg_to_buf(struct mmc_omap_host *host)
644 {
645 	struct scatterlist *sg;
646 
647 	sg = host->data->sg + host->sg_idx;
648 	host->buffer_bytes_left = sg->length;
649 	host->buffer = sg_virt(sg);
650 	if (host->buffer_bytes_left > host->total_bytes_left)
651 		host->buffer_bytes_left = host->total_bytes_left;
652 }
653 
654 static void
655 mmc_omap_clk_timer(struct timer_list *t)
656 {
657 	struct mmc_omap_host *host = from_timer(host, t, clk_timer);
658 
659 	mmc_omap_fclk_enable(host, 0);
660 }
661 
662 /* PIO only */
663 static void
664 mmc_omap_xfer_data(struct mmc_omap_host *host, int write)
665 {
666 	int n, nwords;
667 
668 	if (host->buffer_bytes_left == 0) {
669 		host->sg_idx++;
670 		BUG_ON(host->sg_idx == host->sg_len);
671 		mmc_omap_sg_to_buf(host);
672 	}
673 	n = 64;
674 	if (n > host->buffer_bytes_left)
675 		n = host->buffer_bytes_left;
676 
677 	/* Round up to handle odd number of bytes to transfer */
678 	nwords = DIV_ROUND_UP(n, 2);
679 
680 	host->buffer_bytes_left -= n;
681 	host->total_bytes_left -= n;
682 	host->data->bytes_xfered += n;
683 
684 	if (write) {
685 		__raw_writesw(host->virt_base + OMAP_MMC_REG(host, DATA),
686 			      host->buffer, nwords);
687 	} else {
688 		__raw_readsw(host->virt_base + OMAP_MMC_REG(host, DATA),
689 			     host->buffer, nwords);
690 	}
691 
692 	host->buffer += nwords;
693 }
694 
695 #ifdef CONFIG_MMC_DEBUG
696 static void mmc_omap_report_irq(struct mmc_omap_host *host, u16 status)
697 {
698 	static const char *mmc_omap_status_bits[] = {
699 		"EOC", "CD", "CB", "BRS", "EOFB", "DTO", "DCRC", "CTO",
700 		"CCRC", "CRW", "AF", "AE", "OCRB", "CIRQ", "CERR"
701 	};
702 	int i;
703 	char res[64], *buf = res;
704 
705 	buf += sprintf(buf, "MMC IRQ 0x%x:", status);
706 
707 	for (i = 0; i < ARRAY_SIZE(mmc_omap_status_bits); i++)
708 		if (status & (1 << i))
709 			buf += sprintf(buf, " %s", mmc_omap_status_bits[i]);
710 	dev_vdbg(mmc_dev(host->mmc), "%s\n", res);
711 }
712 #else
713 static void mmc_omap_report_irq(struct mmc_omap_host *host, u16 status)
714 {
715 }
716 #endif
717 
718 
719 static irqreturn_t mmc_omap_irq(int irq, void *dev_id)
720 {
721 	struct mmc_omap_host * host = (struct mmc_omap_host *)dev_id;
722 	u16 status;
723 	int end_command;
724 	int end_transfer;
725 	int transfer_error, cmd_error;
726 
727 	if (host->cmd == NULL && host->data == NULL) {
728 		status = OMAP_MMC_READ(host, STAT);
729 		dev_info(mmc_dev(host->slots[0]->mmc),
730 			 "Spurious IRQ 0x%04x\n", status);
731 		if (status != 0) {
732 			OMAP_MMC_WRITE(host, STAT, status);
733 			OMAP_MMC_WRITE(host, IE, 0);
734 		}
735 		return IRQ_HANDLED;
736 	}
737 
738 	end_command = 0;
739 	end_transfer = 0;
740 	transfer_error = 0;
741 	cmd_error = 0;
742 
743 	while ((status = OMAP_MMC_READ(host, STAT)) != 0) {
744 		int cmd;
745 
746 		OMAP_MMC_WRITE(host, STAT, status);
747 		if (host->cmd != NULL)
748 			cmd = host->cmd->opcode;
749 		else
750 			cmd = -1;
751 		dev_dbg(mmc_dev(host->mmc), "MMC IRQ %04x (CMD %d): ",
752 			status, cmd);
753 		mmc_omap_report_irq(host, status);
754 
755 		if (host->total_bytes_left) {
756 			if ((status & OMAP_MMC_STAT_A_FULL) ||
757 			    (status & OMAP_MMC_STAT_END_OF_DATA))
758 				mmc_omap_xfer_data(host, 0);
759 			if (status & OMAP_MMC_STAT_A_EMPTY)
760 				mmc_omap_xfer_data(host, 1);
761 		}
762 
763 		if (status & OMAP_MMC_STAT_END_OF_DATA)
764 			end_transfer = 1;
765 
766 		if (status & OMAP_MMC_STAT_DATA_TOUT) {
767 			dev_dbg(mmc_dev(host->mmc), "data timeout (CMD%d)\n",
768 				cmd);
769 			if (host->data) {
770 				host->data->error = -ETIMEDOUT;
771 				transfer_error = 1;
772 			}
773 		}
774 
775 		if (status & OMAP_MMC_STAT_DATA_CRC) {
776 			if (host->data) {
777 				host->data->error = -EILSEQ;
778 				dev_dbg(mmc_dev(host->mmc),
779 					 "data CRC error, bytes left %d\n",
780 					host->total_bytes_left);
781 				transfer_error = 1;
782 			} else {
783 				dev_dbg(mmc_dev(host->mmc), "data CRC error\n");
784 			}
785 		}
786 
787 		if (status & OMAP_MMC_STAT_CMD_TOUT) {
788 			/* Timeouts are routine with some commands */
789 			if (host->cmd) {
790 				struct mmc_omap_slot *slot =
791 					host->current_slot;
792 				if (slot == NULL ||
793 				    !mmc_omap_cover_is_open(slot))
794 					dev_err(mmc_dev(host->mmc),
795 						"command timeout (CMD%d)\n",
796 						cmd);
797 				host->cmd->error = -ETIMEDOUT;
798 				end_command = 1;
799 				cmd_error = 1;
800 			}
801 		}
802 
803 		if (status & OMAP_MMC_STAT_CMD_CRC) {
804 			if (host->cmd) {
805 				dev_err(mmc_dev(host->mmc),
806 					"command CRC error (CMD%d, arg 0x%08x)\n",
807 					cmd, host->cmd->arg);
808 				host->cmd->error = -EILSEQ;
809 				end_command = 1;
810 				cmd_error = 1;
811 			} else
812 				dev_err(mmc_dev(host->mmc),
813 					"command CRC error without cmd?\n");
814 		}
815 
816 		if (status & OMAP_MMC_STAT_CARD_ERR) {
817 			dev_dbg(mmc_dev(host->mmc),
818 				"ignoring card status error (CMD%d)\n",
819 				cmd);
820 			end_command = 1;
821 		}
822 
823 		/*
824 		 * NOTE: On 1610 the END_OF_CMD may come too early when
825 		 * starting a write
826 		 */
827 		if ((status & OMAP_MMC_STAT_END_OF_CMD) &&
828 		    (!(status & OMAP_MMC_STAT_A_EMPTY))) {
829 			end_command = 1;
830 		}
831 	}
832 
833 	if (cmd_error && host->data) {
834 		del_timer(&host->cmd_abort_timer);
835 		host->abort = 1;
836 		OMAP_MMC_WRITE(host, IE, 0);
837 		disable_irq_nosync(host->irq);
838 		queue_work(host->mmc_omap_wq, &host->cmd_abort_work);
839 		return IRQ_HANDLED;
840 	}
841 
842 	if (end_command && host->cmd)
843 		mmc_omap_cmd_done(host, host->cmd);
844 	if (host->data != NULL) {
845 		if (transfer_error)
846 			mmc_omap_xfer_done(host, host->data);
847 		else if (end_transfer)
848 			mmc_omap_end_of_data(host, host->data);
849 	}
850 
851 	return IRQ_HANDLED;
852 }
853 
854 void omap_mmc_notify_cover_event(struct device *dev, int num, int is_closed)
855 {
856 	int cover_open;
857 	struct mmc_omap_host *host = dev_get_drvdata(dev);
858 	struct mmc_omap_slot *slot = host->slots[num];
859 
860 	BUG_ON(num >= host->nr_slots);
861 
862 	/* Other subsystems can call in here before we're initialised. */
863 	if (host->nr_slots == 0 || !host->slots[num])
864 		return;
865 
866 	cover_open = mmc_omap_cover_is_open(slot);
867 	if (cover_open != slot->cover_open) {
868 		slot->cover_open = cover_open;
869 		sysfs_notify(&slot->mmc->class_dev.kobj, NULL, "cover_switch");
870 	}
871 
872 	tasklet_hi_schedule(&slot->cover_tasklet);
873 }
874 
875 static void mmc_omap_cover_timer(struct timer_list *t)
876 {
877 	struct mmc_omap_slot *slot = from_timer(slot, t, cover_timer);
878 	tasklet_schedule(&slot->cover_tasklet);
879 }
880 
881 static void mmc_omap_cover_handler(struct tasklet_struct *t)
882 {
883 	struct mmc_omap_slot *slot = from_tasklet(slot, t, cover_tasklet);
884 	int cover_open = mmc_omap_cover_is_open(slot);
885 
886 	mmc_detect_change(slot->mmc, 0);
887 	if (!cover_open)
888 		return;
889 
890 	/*
891 	 * If no card is inserted, we postpone polling until
892 	 * the cover has been closed.
893 	 */
894 	if (slot->mmc->card == NULL)
895 		return;
896 
897 	mod_timer(&slot->cover_timer,
898 		  jiffies + msecs_to_jiffies(OMAP_MMC_COVER_POLL_DELAY));
899 }
900 
901 static void mmc_omap_dma_callback(void *priv)
902 {
903 	struct mmc_omap_host *host = priv;
904 	struct mmc_data *data = host->data;
905 
906 	/* If we got to the end of DMA, assume everything went well */
907 	data->bytes_xfered += data->blocks * data->blksz;
908 
909 	mmc_omap_dma_done(host, data);
910 }
911 
912 static inline void set_cmd_timeout(struct mmc_omap_host *host, struct mmc_request *req)
913 {
914 	u16 reg;
915 
916 	reg = OMAP_MMC_READ(host, SDIO);
917 	reg &= ~(1 << 5);
918 	OMAP_MMC_WRITE(host, SDIO, reg);
919 	/* Set maximum timeout */
920 	OMAP_MMC_WRITE(host, CTO, 0xfd);
921 }
922 
923 static inline void set_data_timeout(struct mmc_omap_host *host, struct mmc_request *req)
924 {
925 	unsigned int timeout, cycle_ns;
926 	u16 reg;
927 
928 	cycle_ns = 1000000000 / host->current_slot->fclk_freq;
929 	timeout = req->data->timeout_ns / cycle_ns;
930 	timeout += req->data->timeout_clks;
931 
932 	/* Check if we need to use timeout multiplier register */
933 	reg = OMAP_MMC_READ(host, SDIO);
934 	if (timeout > 0xffff) {
935 		reg |= (1 << 5);
936 		timeout /= 1024;
937 	} else
938 		reg &= ~(1 << 5);
939 	OMAP_MMC_WRITE(host, SDIO, reg);
940 	OMAP_MMC_WRITE(host, DTO, timeout);
941 }
942 
943 static void
944 mmc_omap_prepare_data(struct mmc_omap_host *host, struct mmc_request *req)
945 {
946 	struct mmc_data *data = req->data;
947 	int i, use_dma = 1, block_size;
948 	struct scatterlist *sg;
949 	unsigned sg_len;
950 
951 	host->data = data;
952 	if (data == NULL) {
953 		OMAP_MMC_WRITE(host, BLEN, 0);
954 		OMAP_MMC_WRITE(host, NBLK, 0);
955 		OMAP_MMC_WRITE(host, BUF, 0);
956 		host->dma_in_use = 0;
957 		set_cmd_timeout(host, req);
958 		return;
959 	}
960 
961 	block_size = data->blksz;
962 
963 	OMAP_MMC_WRITE(host, NBLK, data->blocks - 1);
964 	OMAP_MMC_WRITE(host, BLEN, block_size - 1);
965 	set_data_timeout(host, req);
966 
967 	/* cope with calling layer confusion; it issues "single
968 	 * block" writes using multi-block scatterlists.
969 	 */
970 	sg_len = (data->blocks == 1) ? 1 : data->sg_len;
971 
972 	/* Only do DMA for entire blocks */
973 	for_each_sg(data->sg, sg, sg_len, i) {
974 		if ((sg->length % block_size) != 0) {
975 			use_dma = 0;
976 			break;
977 		}
978 	}
979 
980 	host->sg_idx = 0;
981 	if (use_dma) {
982 		enum dma_data_direction dma_data_dir;
983 		struct dma_async_tx_descriptor *tx;
984 		struct dma_chan *c;
985 		u32 burst, *bp;
986 		u16 buf;
987 
988 		/*
989 		 * FIFO is 16x2 bytes on 15xx, and 32x2 bytes on 16xx
990 		 * and 24xx. Use 16 or 32 word frames when the
991 		 * blocksize is at least that large. Blocksize is
992 		 * usually 512 bytes; but not for some SD reads.
993 		 */
994 		burst = mmc_omap15xx() ? 32 : 64;
995 		if (burst > data->blksz)
996 			burst = data->blksz;
997 
998 		burst >>= 1;
999 
1000 		if (data->flags & MMC_DATA_WRITE) {
1001 			c = host->dma_tx;
1002 			bp = &host->dma_tx_burst;
1003 			buf = 0x0f80 | (burst - 1) << 0;
1004 			dma_data_dir = DMA_TO_DEVICE;
1005 		} else {
1006 			c = host->dma_rx;
1007 			bp = &host->dma_rx_burst;
1008 			buf = 0x800f | (burst - 1) << 8;
1009 			dma_data_dir = DMA_FROM_DEVICE;
1010 		}
1011 
1012 		if (!c)
1013 			goto use_pio;
1014 
1015 		/* Only reconfigure if we have a different burst size */
1016 		if (*bp != burst) {
1017 			struct dma_slave_config cfg = {
1018 				.src_addr = host->phys_base +
1019 					    OMAP_MMC_REG(host, DATA),
1020 				.dst_addr = host->phys_base +
1021 					    OMAP_MMC_REG(host, DATA),
1022 				.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES,
1023 				.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES,
1024 				.src_maxburst = burst,
1025 				.dst_maxburst = burst,
1026 			};
1027 
1028 			if (dmaengine_slave_config(c, &cfg))
1029 				goto use_pio;
1030 
1031 			*bp = burst;
1032 		}
1033 
1034 		host->sg_len = dma_map_sg(c->device->dev, data->sg, sg_len,
1035 					  dma_data_dir);
1036 		if (host->sg_len == 0)
1037 			goto use_pio;
1038 
1039 		tx = dmaengine_prep_slave_sg(c, data->sg, host->sg_len,
1040 			data->flags & MMC_DATA_WRITE ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM,
1041 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1042 		if (!tx)
1043 			goto use_pio;
1044 
1045 		OMAP_MMC_WRITE(host, BUF, buf);
1046 
1047 		tx->callback = mmc_omap_dma_callback;
1048 		tx->callback_param = host;
1049 		dmaengine_submit(tx);
1050 		host->brs_received = 0;
1051 		host->dma_done = 0;
1052 		host->dma_in_use = 1;
1053 		return;
1054 	}
1055  use_pio:
1056 
1057 	/* Revert to PIO? */
1058 	OMAP_MMC_WRITE(host, BUF, 0x1f1f);
1059 	host->total_bytes_left = data->blocks * block_size;
1060 	host->sg_len = sg_len;
1061 	mmc_omap_sg_to_buf(host);
1062 	host->dma_in_use = 0;
1063 }
1064 
1065 static void mmc_omap_start_request(struct mmc_omap_host *host,
1066 				   struct mmc_request *req)
1067 {
1068 	BUG_ON(host->mrq != NULL);
1069 
1070 	host->mrq = req;
1071 
1072 	/* only touch fifo AFTER the controller readies it */
1073 	mmc_omap_prepare_data(host, req);
1074 	mmc_omap_start_command(host, req->cmd);
1075 	if (host->dma_in_use) {
1076 		struct dma_chan *c = host->data->flags & MMC_DATA_WRITE ?
1077 				host->dma_tx : host->dma_rx;
1078 
1079 		dma_async_issue_pending(c);
1080 	}
1081 }
1082 
1083 static void mmc_omap_request(struct mmc_host *mmc, struct mmc_request *req)
1084 {
1085 	struct mmc_omap_slot *slot = mmc_priv(mmc);
1086 	struct mmc_omap_host *host = slot->host;
1087 	unsigned long flags;
1088 
1089 	spin_lock_irqsave(&host->slot_lock, flags);
1090 	if (host->mmc != NULL) {
1091 		BUG_ON(slot->mrq != NULL);
1092 		slot->mrq = req;
1093 		spin_unlock_irqrestore(&host->slot_lock, flags);
1094 		return;
1095 	} else
1096 		host->mmc = mmc;
1097 	spin_unlock_irqrestore(&host->slot_lock, flags);
1098 	mmc_omap_select_slot(slot, 1);
1099 	mmc_omap_start_request(host, req);
1100 }
1101 
1102 static void mmc_omap_set_power(struct mmc_omap_slot *slot, int power_on,
1103 				int vdd)
1104 {
1105 	struct mmc_omap_host *host;
1106 
1107 	host = slot->host;
1108 
1109 	if (slot->pdata->set_power != NULL)
1110 		slot->pdata->set_power(mmc_dev(slot->mmc), slot->id, power_on,
1111 					vdd);
1112 	if (mmc_omap2()) {
1113 		u16 w;
1114 
1115 		if (power_on) {
1116 			w = OMAP_MMC_READ(host, CON);
1117 			OMAP_MMC_WRITE(host, CON, w | (1 << 11));
1118 		} else {
1119 			w = OMAP_MMC_READ(host, CON);
1120 			OMAP_MMC_WRITE(host, CON, w & ~(1 << 11));
1121 		}
1122 	}
1123 }
1124 
1125 static int mmc_omap_calc_divisor(struct mmc_host *mmc, struct mmc_ios *ios)
1126 {
1127 	struct mmc_omap_slot *slot = mmc_priv(mmc);
1128 	struct mmc_omap_host *host = slot->host;
1129 	int func_clk_rate = clk_get_rate(host->fclk);
1130 	int dsor;
1131 
1132 	if (ios->clock == 0)
1133 		return 0;
1134 
1135 	dsor = func_clk_rate / ios->clock;
1136 	if (dsor < 1)
1137 		dsor = 1;
1138 
1139 	if (func_clk_rate / dsor > ios->clock)
1140 		dsor++;
1141 
1142 	if (dsor > 250)
1143 		dsor = 250;
1144 
1145 	slot->fclk_freq = func_clk_rate / dsor;
1146 
1147 	if (ios->bus_width == MMC_BUS_WIDTH_4)
1148 		dsor |= 1 << 15;
1149 
1150 	return dsor;
1151 }
1152 
1153 static void mmc_omap_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
1154 {
1155 	struct mmc_omap_slot *slot = mmc_priv(mmc);
1156 	struct mmc_omap_host *host = slot->host;
1157 	int i, dsor;
1158 	int clk_enabled, init_stream;
1159 
1160 	mmc_omap_select_slot(slot, 0);
1161 
1162 	dsor = mmc_omap_calc_divisor(mmc, ios);
1163 
1164 	if (ios->vdd != slot->vdd)
1165 		slot->vdd = ios->vdd;
1166 
1167 	clk_enabled = 0;
1168 	init_stream = 0;
1169 	switch (ios->power_mode) {
1170 	case MMC_POWER_OFF:
1171 		mmc_omap_set_power(slot, 0, ios->vdd);
1172 		break;
1173 	case MMC_POWER_UP:
1174 		/* Cannot touch dsor yet, just power up MMC */
1175 		mmc_omap_set_power(slot, 1, ios->vdd);
1176 		slot->power_mode = ios->power_mode;
1177 		goto exit;
1178 	case MMC_POWER_ON:
1179 		mmc_omap_fclk_enable(host, 1);
1180 		clk_enabled = 1;
1181 		dsor |= 1 << 11;
1182 		if (slot->power_mode != MMC_POWER_ON)
1183 			init_stream = 1;
1184 		break;
1185 	}
1186 	slot->power_mode = ios->power_mode;
1187 
1188 	if (slot->bus_mode != ios->bus_mode) {
1189 		if (slot->pdata->set_bus_mode != NULL)
1190 			slot->pdata->set_bus_mode(mmc_dev(mmc), slot->id,
1191 						  ios->bus_mode);
1192 		slot->bus_mode = ios->bus_mode;
1193 	}
1194 
1195 	/* On insanely high arm_per frequencies something sometimes
1196 	 * goes somehow out of sync, and the POW bit is not being set,
1197 	 * which results in the while loop below getting stuck.
1198 	 * Writing to the CON register twice seems to do the trick. */
1199 	for (i = 0; i < 2; i++)
1200 		OMAP_MMC_WRITE(host, CON, dsor);
1201 	slot->saved_con = dsor;
1202 	if (init_stream) {
1203 		/* worst case at 400kHz, 80 cycles makes 200 microsecs */
1204 		int usecs = 250;
1205 
1206 		/* Send clock cycles, poll completion */
1207 		OMAP_MMC_WRITE(host, IE, 0);
1208 		OMAP_MMC_WRITE(host, STAT, 0xffff);
1209 		OMAP_MMC_WRITE(host, CMD, 1 << 7);
1210 		while (usecs > 0 && (OMAP_MMC_READ(host, STAT) & 1) == 0) {
1211 			udelay(1);
1212 			usecs--;
1213 		}
1214 		OMAP_MMC_WRITE(host, STAT, 1);
1215 	}
1216 
1217 exit:
1218 	mmc_omap_release_slot(slot, clk_enabled);
1219 }
1220 
1221 static const struct mmc_host_ops mmc_omap_ops = {
1222 	.request	= mmc_omap_request,
1223 	.set_ios	= mmc_omap_set_ios,
1224 };
1225 
1226 static int mmc_omap_new_slot(struct mmc_omap_host *host, int id)
1227 {
1228 	struct mmc_omap_slot *slot = NULL;
1229 	struct mmc_host *mmc;
1230 	int r;
1231 
1232 	mmc = mmc_alloc_host(sizeof(struct mmc_omap_slot), host->dev);
1233 	if (mmc == NULL)
1234 		return -ENOMEM;
1235 
1236 	slot = mmc_priv(mmc);
1237 	slot->host = host;
1238 	slot->mmc = mmc;
1239 	slot->id = id;
1240 	slot->power_mode = MMC_POWER_UNDEFINED;
1241 	slot->pdata = &host->pdata->slots[id];
1242 
1243 	host->slots[id] = slot;
1244 
1245 	mmc->caps = 0;
1246 	if (host->pdata->slots[id].wires >= 4)
1247 		mmc->caps |= MMC_CAP_4_BIT_DATA;
1248 
1249 	mmc->ops = &mmc_omap_ops;
1250 	mmc->f_min = 400000;
1251 
1252 	if (mmc_omap2())
1253 		mmc->f_max = 48000000;
1254 	else
1255 		mmc->f_max = 24000000;
1256 	if (host->pdata->max_freq)
1257 		mmc->f_max = min(host->pdata->max_freq, mmc->f_max);
1258 	mmc->ocr_avail = slot->pdata->ocr_mask;
1259 
1260 	/* Use scatterlist DMA to reduce per-transfer costs.
1261 	 * NOTE max_seg_size assumption that small blocks aren't
1262 	 * normally used (except e.g. for reading SD registers).
1263 	 */
1264 	mmc->max_segs = 32;
1265 	mmc->max_blk_size = 2048;	/* BLEN is 11 bits (+1) */
1266 	mmc->max_blk_count = 2048;	/* NBLK is 11 bits (+1) */
1267 	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
1268 	mmc->max_seg_size = mmc->max_req_size;
1269 
1270 	if (slot->pdata->get_cover_state != NULL) {
1271 		timer_setup(&slot->cover_timer, mmc_omap_cover_timer, 0);
1272 		tasklet_setup(&slot->cover_tasklet, mmc_omap_cover_handler);
1273 	}
1274 
1275 	r = mmc_add_host(mmc);
1276 	if (r < 0)
1277 		goto err_remove_host;
1278 
1279 	if (slot->pdata->name != NULL) {
1280 		r = device_create_file(&mmc->class_dev,
1281 					&dev_attr_slot_name);
1282 		if (r < 0)
1283 			goto err_remove_host;
1284 	}
1285 
1286 	if (slot->pdata->get_cover_state != NULL) {
1287 		r = device_create_file(&mmc->class_dev,
1288 					&dev_attr_cover_switch);
1289 		if (r < 0)
1290 			goto err_remove_slot_name;
1291 		tasklet_schedule(&slot->cover_tasklet);
1292 	}
1293 
1294 	return 0;
1295 
1296 err_remove_slot_name:
1297 	if (slot->pdata->name != NULL)
1298 		device_remove_file(&mmc->class_dev, &dev_attr_slot_name);
1299 err_remove_host:
1300 	mmc_remove_host(mmc);
1301 	mmc_free_host(mmc);
1302 	return r;
1303 }
1304 
1305 static void mmc_omap_remove_slot(struct mmc_omap_slot *slot)
1306 {
1307 	struct mmc_host *mmc = slot->mmc;
1308 
1309 	if (slot->pdata->name != NULL)
1310 		device_remove_file(&mmc->class_dev, &dev_attr_slot_name);
1311 	if (slot->pdata->get_cover_state != NULL)
1312 		device_remove_file(&mmc->class_dev, &dev_attr_cover_switch);
1313 
1314 	tasklet_kill(&slot->cover_tasklet);
1315 	del_timer_sync(&slot->cover_timer);
1316 	flush_workqueue(slot->host->mmc_omap_wq);
1317 
1318 	mmc_remove_host(mmc);
1319 	mmc_free_host(mmc);
1320 }
1321 
1322 static int mmc_omap_probe(struct platform_device *pdev)
1323 {
1324 	struct omap_mmc_platform_data *pdata = pdev->dev.platform_data;
1325 	struct mmc_omap_host *host = NULL;
1326 	struct resource *res;
1327 	int i, ret = 0;
1328 	int irq;
1329 
1330 	if (pdata == NULL) {
1331 		dev_err(&pdev->dev, "platform data missing\n");
1332 		return -ENXIO;
1333 	}
1334 	if (pdata->nr_slots == 0) {
1335 		dev_err(&pdev->dev, "no slots\n");
1336 		return -EPROBE_DEFER;
1337 	}
1338 
1339 	host = devm_kzalloc(&pdev->dev, sizeof(struct mmc_omap_host),
1340 			    GFP_KERNEL);
1341 	if (host == NULL)
1342 		return -ENOMEM;
1343 
1344 	irq = platform_get_irq(pdev, 0);
1345 	if (irq < 0)
1346 		return -ENXIO;
1347 
1348 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1349 	host->virt_base = devm_ioremap_resource(&pdev->dev, res);
1350 	if (IS_ERR(host->virt_base))
1351 		return PTR_ERR(host->virt_base);
1352 
1353 	INIT_WORK(&host->slot_release_work, mmc_omap_slot_release_work);
1354 	INIT_WORK(&host->send_stop_work, mmc_omap_send_stop_work);
1355 
1356 	INIT_WORK(&host->cmd_abort_work, mmc_omap_abort_command);
1357 	timer_setup(&host->cmd_abort_timer, mmc_omap_cmd_timer, 0);
1358 
1359 	spin_lock_init(&host->clk_lock);
1360 	timer_setup(&host->clk_timer, mmc_omap_clk_timer, 0);
1361 
1362 	spin_lock_init(&host->dma_lock);
1363 	spin_lock_init(&host->slot_lock);
1364 	init_waitqueue_head(&host->slot_wq);
1365 
1366 	host->pdata = pdata;
1367 	host->features = host->pdata->slots[0].features;
1368 	host->dev = &pdev->dev;
1369 	platform_set_drvdata(pdev, host);
1370 
1371 	host->id = pdev->id;
1372 	host->irq = irq;
1373 	host->phys_base = res->start;
1374 	host->iclk = clk_get(&pdev->dev, "ick");
1375 	if (IS_ERR(host->iclk))
1376 		return PTR_ERR(host->iclk);
1377 	clk_enable(host->iclk);
1378 
1379 	host->fclk = clk_get(&pdev->dev, "fck");
1380 	if (IS_ERR(host->fclk)) {
1381 		ret = PTR_ERR(host->fclk);
1382 		goto err_free_iclk;
1383 	}
1384 
1385 	host->dma_tx_burst = -1;
1386 	host->dma_rx_burst = -1;
1387 
1388 	host->dma_tx = dma_request_chan(&pdev->dev, "tx");
1389 	if (IS_ERR(host->dma_tx)) {
1390 		ret = PTR_ERR(host->dma_tx);
1391 		if (ret == -EPROBE_DEFER) {
1392 			clk_put(host->fclk);
1393 			goto err_free_iclk;
1394 		}
1395 
1396 		host->dma_tx = NULL;
1397 		dev_warn(host->dev, "TX DMA channel request failed\n");
1398 	}
1399 
1400 	host->dma_rx = dma_request_chan(&pdev->dev, "rx");
1401 	if (IS_ERR(host->dma_rx)) {
1402 		ret = PTR_ERR(host->dma_rx);
1403 		if (ret == -EPROBE_DEFER) {
1404 			if (host->dma_tx)
1405 				dma_release_channel(host->dma_tx);
1406 			clk_put(host->fclk);
1407 			goto err_free_iclk;
1408 		}
1409 
1410 		host->dma_rx = NULL;
1411 		dev_warn(host->dev, "RX DMA channel request failed\n");
1412 	}
1413 
1414 	ret = request_irq(host->irq, mmc_omap_irq, 0, DRIVER_NAME, host);
1415 	if (ret)
1416 		goto err_free_dma;
1417 
1418 	if (pdata->init != NULL) {
1419 		ret = pdata->init(&pdev->dev);
1420 		if (ret < 0)
1421 			goto err_free_irq;
1422 	}
1423 
1424 	host->nr_slots = pdata->nr_slots;
1425 	host->reg_shift = (mmc_omap7xx() ? 1 : 2);
1426 
1427 	host->mmc_omap_wq = alloc_workqueue("mmc_omap", 0, 0);
1428 	if (!host->mmc_omap_wq) {
1429 		ret = -ENOMEM;
1430 		goto err_plat_cleanup;
1431 	}
1432 
1433 	for (i = 0; i < pdata->nr_slots; i++) {
1434 		ret = mmc_omap_new_slot(host, i);
1435 		if (ret < 0) {
1436 			while (--i >= 0)
1437 				mmc_omap_remove_slot(host->slots[i]);
1438 
1439 			goto err_destroy_wq;
1440 		}
1441 	}
1442 
1443 	return 0;
1444 
1445 err_destroy_wq:
1446 	destroy_workqueue(host->mmc_omap_wq);
1447 err_plat_cleanup:
1448 	if (pdata->cleanup)
1449 		pdata->cleanup(&pdev->dev);
1450 err_free_irq:
1451 	free_irq(host->irq, host);
1452 err_free_dma:
1453 	if (host->dma_tx)
1454 		dma_release_channel(host->dma_tx);
1455 	if (host->dma_rx)
1456 		dma_release_channel(host->dma_rx);
1457 	clk_put(host->fclk);
1458 err_free_iclk:
1459 	clk_disable(host->iclk);
1460 	clk_put(host->iclk);
1461 	return ret;
1462 }
1463 
1464 static int mmc_omap_remove(struct platform_device *pdev)
1465 {
1466 	struct mmc_omap_host *host = platform_get_drvdata(pdev);
1467 	int i;
1468 
1469 	BUG_ON(host == NULL);
1470 
1471 	for (i = 0; i < host->nr_slots; i++)
1472 		mmc_omap_remove_slot(host->slots[i]);
1473 
1474 	if (host->pdata->cleanup)
1475 		host->pdata->cleanup(&pdev->dev);
1476 
1477 	mmc_omap_fclk_enable(host, 0);
1478 	free_irq(host->irq, host);
1479 	clk_put(host->fclk);
1480 	clk_disable(host->iclk);
1481 	clk_put(host->iclk);
1482 
1483 	if (host->dma_tx)
1484 		dma_release_channel(host->dma_tx);
1485 	if (host->dma_rx)
1486 		dma_release_channel(host->dma_rx);
1487 
1488 	destroy_workqueue(host->mmc_omap_wq);
1489 
1490 	return 0;
1491 }
1492 
1493 #if IS_BUILTIN(CONFIG_OF)
1494 static const struct of_device_id mmc_omap_match[] = {
1495 	{ .compatible = "ti,omap2420-mmc", },
1496 	{ },
1497 };
1498 MODULE_DEVICE_TABLE(of, mmc_omap_match);
1499 #endif
1500 
1501 static struct platform_driver mmc_omap_driver = {
1502 	.probe		= mmc_omap_probe,
1503 	.remove		= mmc_omap_remove,
1504 	.driver		= {
1505 		.name	= DRIVER_NAME,
1506 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1507 		.of_match_table = of_match_ptr(mmc_omap_match),
1508 	},
1509 };
1510 
1511 module_platform_driver(mmc_omap_driver);
1512 MODULE_DESCRIPTION("OMAP Multimedia Card driver");
1513 MODULE_LICENSE("GPL");
1514 MODULE_ALIAS("platform:" DRIVER_NAME);
1515 MODULE_AUTHOR("Juha Yrjölä");
1516