xref: /openbmc/linux/drivers/mmc/host/omap.c (revision 2a598d0b)
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/gpio/consumer.h>
30 #include <linux/platform_data/mmc-omap.h>
31 
32 
33 #define	OMAP_MMC_REG_CMD	0x00
34 #define	OMAP_MMC_REG_ARGL	0x01
35 #define	OMAP_MMC_REG_ARGH	0x02
36 #define	OMAP_MMC_REG_CON	0x03
37 #define	OMAP_MMC_REG_STAT	0x04
38 #define	OMAP_MMC_REG_IE		0x05
39 #define	OMAP_MMC_REG_CTO	0x06
40 #define	OMAP_MMC_REG_DTO	0x07
41 #define	OMAP_MMC_REG_DATA	0x08
42 #define	OMAP_MMC_REG_BLEN	0x09
43 #define	OMAP_MMC_REG_NBLK	0x0a
44 #define	OMAP_MMC_REG_BUF	0x0b
45 #define	OMAP_MMC_REG_SDIO	0x0d
46 #define	OMAP_MMC_REG_REV	0x0f
47 #define	OMAP_MMC_REG_RSP0	0x10
48 #define	OMAP_MMC_REG_RSP1	0x11
49 #define	OMAP_MMC_REG_RSP2	0x12
50 #define	OMAP_MMC_REG_RSP3	0x13
51 #define	OMAP_MMC_REG_RSP4	0x14
52 #define	OMAP_MMC_REG_RSP5	0x15
53 #define	OMAP_MMC_REG_RSP6	0x16
54 #define	OMAP_MMC_REG_RSP7	0x17
55 #define	OMAP_MMC_REG_IOSR	0x18
56 #define	OMAP_MMC_REG_SYSC	0x19
57 #define	OMAP_MMC_REG_SYSS	0x1a
58 
59 #define	OMAP_MMC_STAT_CARD_ERR		(1 << 14)
60 #define	OMAP_MMC_STAT_CARD_IRQ		(1 << 13)
61 #define	OMAP_MMC_STAT_OCR_BUSY		(1 << 12)
62 #define	OMAP_MMC_STAT_A_EMPTY		(1 << 11)
63 #define	OMAP_MMC_STAT_A_FULL		(1 << 10)
64 #define	OMAP_MMC_STAT_CMD_CRC		(1 <<  8)
65 #define	OMAP_MMC_STAT_CMD_TOUT		(1 <<  7)
66 #define	OMAP_MMC_STAT_DATA_CRC		(1 <<  6)
67 #define	OMAP_MMC_STAT_DATA_TOUT		(1 <<  5)
68 #define	OMAP_MMC_STAT_END_BUSY		(1 <<  4)
69 #define	OMAP_MMC_STAT_END_OF_DATA	(1 <<  3)
70 #define	OMAP_MMC_STAT_CARD_BUSY		(1 <<  2)
71 #define	OMAP_MMC_STAT_END_OF_CMD	(1 <<  0)
72 
73 #define mmc_omap7xx()	(host->features & MMC_OMAP7XX)
74 #define mmc_omap15xx()	(host->features & MMC_OMAP15XX)
75 #define mmc_omap16xx()	(host->features & MMC_OMAP16XX)
76 #define MMC_OMAP1_MASK	(MMC_OMAP7XX | MMC_OMAP15XX | MMC_OMAP16XX)
77 #define mmc_omap1()	(host->features & MMC_OMAP1_MASK)
78 #define mmc_omap2()	(!mmc_omap1())
79 
80 #define OMAP_MMC_REG(host, reg)		(OMAP_MMC_REG_##reg << (host)->reg_shift)
81 #define OMAP_MMC_READ(host, reg)	__raw_readw((host)->virt_base + OMAP_MMC_REG(host, reg))
82 #define OMAP_MMC_WRITE(host, reg, val)	__raw_writew((val), (host)->virt_base + OMAP_MMC_REG(host, reg))
83 
84 /*
85  * Command types
86  */
87 #define OMAP_MMC_CMDTYPE_BC	0
88 #define OMAP_MMC_CMDTYPE_BCR	1
89 #define OMAP_MMC_CMDTYPE_AC	2
90 #define OMAP_MMC_CMDTYPE_ADTC	3
91 
92 #define DRIVER_NAME "mmci-omap"
93 
94 /* Specifies how often in millisecs to poll for card status changes
95  * when the cover switch is open */
96 #define OMAP_MMC_COVER_POLL_DELAY	500
97 
98 struct mmc_omap_host;
99 
100 struct mmc_omap_slot {
101 	int			id;
102 	unsigned int		vdd;
103 	u16			saved_con;
104 	u16			bus_mode;
105 	u16			power_mode;
106 	unsigned int		fclk_freq;
107 
108 	struct tasklet_struct	cover_tasklet;
109 	struct timer_list       cover_timer;
110 	unsigned		cover_open;
111 
112 	struct mmc_request      *mrq;
113 	struct mmc_omap_host    *host;
114 	struct mmc_host		*mmc;
115 	struct gpio_desc	*vsd;
116 	struct gpio_desc	*vio;
117 	struct gpio_desc	*cover;
118 	struct omap_mmc_slot_data *pdata;
119 };
120 
121 struct mmc_omap_host {
122 	int			initialized;
123 	struct mmc_request *	mrq;
124 	struct mmc_command *	cmd;
125 	struct mmc_data *	data;
126 	struct mmc_host *	mmc;
127 	struct device *		dev;
128 	unsigned char		id; /* 16xx chips have 2 MMC blocks */
129 	struct clk *		iclk;
130 	struct clk *		fclk;
131 	struct dma_chan		*dma_rx;
132 	u32			dma_rx_burst;
133 	struct dma_chan		*dma_tx;
134 	u32			dma_tx_burst;
135 	void __iomem		*virt_base;
136 	unsigned int		phys_base;
137 	int			irq;
138 	unsigned char		bus_mode;
139 	unsigned int		reg_shift;
140 	struct gpio_desc	*slot_switch;
141 
142 	struct work_struct	cmd_abort_work;
143 	unsigned		abort:1;
144 	struct timer_list	cmd_abort_timer;
145 
146 	struct work_struct      slot_release_work;
147 	struct mmc_omap_slot    *next_slot;
148 	struct work_struct      send_stop_work;
149 	struct mmc_data		*stop_data;
150 
151 	unsigned int		sg_len;
152 	int			sg_idx;
153 	u16 *			buffer;
154 	u32			buffer_bytes_left;
155 	u32			total_bytes_left;
156 
157 	unsigned		features;
158 	unsigned		brs_received:1, dma_done:1;
159 	unsigned		dma_in_use:1;
160 	spinlock_t		dma_lock;
161 
162 	struct mmc_omap_slot    *slots[OMAP_MMC_MAX_SLOTS];
163 	struct mmc_omap_slot    *current_slot;
164 	spinlock_t              slot_lock;
165 	wait_queue_head_t       slot_wq;
166 	int                     nr_slots;
167 
168 	struct timer_list       clk_timer;
169 	spinlock_t		clk_lock;     /* for changing enabled state */
170 	unsigned int            fclk_enabled:1;
171 	struct workqueue_struct *mmc_omap_wq;
172 
173 	struct omap_mmc_platform_data *pdata;
174 };
175 
176 
177 static void mmc_omap_fclk_offdelay(struct mmc_omap_slot *slot)
178 {
179 	unsigned long tick_ns;
180 
181 	if (slot != NULL && slot->host->fclk_enabled && slot->fclk_freq > 0) {
182 		tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, slot->fclk_freq);
183 		ndelay(8 * tick_ns);
184 	}
185 }
186 
187 static void mmc_omap_fclk_enable(struct mmc_omap_host *host, unsigned int enable)
188 {
189 	unsigned long flags;
190 
191 	spin_lock_irqsave(&host->clk_lock, flags);
192 	if (host->fclk_enabled != enable) {
193 		host->fclk_enabled = enable;
194 		if (enable)
195 			clk_enable(host->fclk);
196 		else
197 			clk_disable(host->fclk);
198 	}
199 	spin_unlock_irqrestore(&host->clk_lock, flags);
200 }
201 
202 static void mmc_omap_select_slot(struct mmc_omap_slot *slot, int claimed)
203 {
204 	struct mmc_omap_host *host = slot->host;
205 	unsigned long flags;
206 
207 	if (claimed)
208 		goto no_claim;
209 	spin_lock_irqsave(&host->slot_lock, flags);
210 	while (host->mmc != NULL) {
211 		spin_unlock_irqrestore(&host->slot_lock, flags);
212 		wait_event(host->slot_wq, host->mmc == NULL);
213 		spin_lock_irqsave(&host->slot_lock, flags);
214 	}
215 	host->mmc = slot->mmc;
216 	spin_unlock_irqrestore(&host->slot_lock, flags);
217 no_claim:
218 	del_timer(&host->clk_timer);
219 	if (host->current_slot != slot || !claimed)
220 		mmc_omap_fclk_offdelay(host->current_slot);
221 
222 	if (host->current_slot != slot) {
223 		OMAP_MMC_WRITE(host, CON, slot->saved_con & 0xFC00);
224 		if (host->slot_switch)
225 			/*
226 			 * With two slots and a simple GPIO switch, setting
227 			 * the GPIO to 0 selects slot ID 0, setting it to 1
228 			 * selects slot ID 1.
229 			 */
230 			gpiod_set_value(host->slot_switch, slot->id);
231 		host->current_slot = slot;
232 	}
233 
234 	if (claimed) {
235 		mmc_omap_fclk_enable(host, 1);
236 
237 		/* Doing the dummy read here seems to work around some bug
238 		 * at least in OMAP24xx silicon where the command would not
239 		 * start after writing the CMD register. Sigh. */
240 		OMAP_MMC_READ(host, CON);
241 
242 		OMAP_MMC_WRITE(host, CON, slot->saved_con);
243 	} else
244 		mmc_omap_fclk_enable(host, 0);
245 }
246 
247 static void mmc_omap_start_request(struct mmc_omap_host *host,
248 				   struct mmc_request *req);
249 
250 static void mmc_omap_slot_release_work(struct work_struct *work)
251 {
252 	struct mmc_omap_host *host = container_of(work, struct mmc_omap_host,
253 						  slot_release_work);
254 	struct mmc_omap_slot *next_slot = host->next_slot;
255 	struct mmc_request *rq;
256 
257 	host->next_slot = NULL;
258 	mmc_omap_select_slot(next_slot, 1);
259 
260 	rq = next_slot->mrq;
261 	next_slot->mrq = NULL;
262 	mmc_omap_start_request(host, rq);
263 }
264 
265 static void mmc_omap_release_slot(struct mmc_omap_slot *slot, int clk_enabled)
266 {
267 	struct mmc_omap_host *host = slot->host;
268 	unsigned long flags;
269 	int i;
270 
271 	BUG_ON(slot == NULL || host->mmc == NULL);
272 
273 	if (clk_enabled)
274 		/* Keeps clock running for at least 8 cycles on valid freq */
275 		mod_timer(&host->clk_timer, jiffies  + HZ/10);
276 	else {
277 		del_timer(&host->clk_timer);
278 		mmc_omap_fclk_offdelay(slot);
279 		mmc_omap_fclk_enable(host, 0);
280 	}
281 
282 	spin_lock_irqsave(&host->slot_lock, flags);
283 	/* Check for any pending requests */
284 	for (i = 0; i < host->nr_slots; i++) {
285 		struct mmc_omap_slot *new_slot;
286 
287 		if (host->slots[i] == NULL || host->slots[i]->mrq == NULL)
288 			continue;
289 
290 		BUG_ON(host->next_slot != NULL);
291 		new_slot = host->slots[i];
292 		/* The current slot should not have a request in queue */
293 		BUG_ON(new_slot == host->current_slot);
294 
295 		host->next_slot = new_slot;
296 		host->mmc = new_slot->mmc;
297 		spin_unlock_irqrestore(&host->slot_lock, flags);
298 		queue_work(host->mmc_omap_wq, &host->slot_release_work);
299 		return;
300 	}
301 
302 	host->mmc = NULL;
303 	wake_up(&host->slot_wq);
304 	spin_unlock_irqrestore(&host->slot_lock, flags);
305 }
306 
307 static inline
308 int mmc_omap_cover_is_open(struct mmc_omap_slot *slot)
309 {
310 	/* If we have a GPIO then use that */
311 	if (slot->cover)
312 		return gpiod_get_value(slot->cover);
313 	if (slot->pdata->get_cover_state)
314 		return slot->pdata->get_cover_state(mmc_dev(slot->mmc),
315 						    slot->id);
316 	return 0;
317 }
318 
319 static ssize_t
320 mmc_omap_show_cover_switch(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", mmc_omap_cover_is_open(slot) ? "open" :
327 		       "closed");
328 }
329 
330 static DEVICE_ATTR(cover_switch, S_IRUGO, mmc_omap_show_cover_switch, NULL);
331 
332 static ssize_t
333 mmc_omap_show_slot_name(struct device *dev, struct device_attribute *attr,
334 			char *buf)
335 {
336 	struct mmc_host *mmc = container_of(dev, struct mmc_host, class_dev);
337 	struct mmc_omap_slot *slot = mmc_priv(mmc);
338 
339 	return sprintf(buf, "%s\n", slot->pdata->name);
340 }
341 
342 static DEVICE_ATTR(slot_name, S_IRUGO, mmc_omap_show_slot_name, NULL);
343 
344 static void
345 mmc_omap_start_command(struct mmc_omap_host *host, struct mmc_command *cmd)
346 {
347 	u32 cmdreg;
348 	u32 resptype;
349 	u32 cmdtype;
350 	u16 irq_mask;
351 
352 	host->cmd = cmd;
353 
354 	resptype = 0;
355 	cmdtype = 0;
356 
357 	/* Our hardware needs to know exact type */
358 	switch (mmc_resp_type(cmd)) {
359 	case MMC_RSP_NONE:
360 		break;
361 	case MMC_RSP_R1:
362 	case MMC_RSP_R1B:
363 		/* resp 1, 1b, 6, 7 */
364 		resptype = 1;
365 		break;
366 	case MMC_RSP_R2:
367 		resptype = 2;
368 		break;
369 	case MMC_RSP_R3:
370 		resptype = 3;
371 		break;
372 	default:
373 		dev_err(mmc_dev(host->mmc), "Invalid response type: %04x\n", mmc_resp_type(cmd));
374 		break;
375 	}
376 
377 	if (mmc_cmd_type(cmd) == MMC_CMD_ADTC) {
378 		cmdtype = OMAP_MMC_CMDTYPE_ADTC;
379 	} else if (mmc_cmd_type(cmd) == MMC_CMD_BC) {
380 		cmdtype = OMAP_MMC_CMDTYPE_BC;
381 	} else if (mmc_cmd_type(cmd) == MMC_CMD_BCR) {
382 		cmdtype = OMAP_MMC_CMDTYPE_BCR;
383 	} else {
384 		cmdtype = OMAP_MMC_CMDTYPE_AC;
385 	}
386 
387 	cmdreg = cmd->opcode | (resptype << 8) | (cmdtype << 12);
388 
389 	if (host->current_slot->bus_mode == MMC_BUSMODE_OPENDRAIN)
390 		cmdreg |= 1 << 6;
391 
392 	if (cmd->flags & MMC_RSP_BUSY)
393 		cmdreg |= 1 << 11;
394 
395 	if (host->data && !(host->data->flags & MMC_DATA_WRITE))
396 		cmdreg |= 1 << 15;
397 
398 	mod_timer(&host->cmd_abort_timer, jiffies + HZ/2);
399 
400 	OMAP_MMC_WRITE(host, CTO, 200);
401 	OMAP_MMC_WRITE(host, ARGL, cmd->arg & 0xffff);
402 	OMAP_MMC_WRITE(host, ARGH, cmd->arg >> 16);
403 	irq_mask = OMAP_MMC_STAT_A_EMPTY    | OMAP_MMC_STAT_A_FULL    |
404 		   OMAP_MMC_STAT_CMD_CRC    | OMAP_MMC_STAT_CMD_TOUT  |
405 		   OMAP_MMC_STAT_DATA_CRC   | OMAP_MMC_STAT_DATA_TOUT |
406 		   OMAP_MMC_STAT_END_OF_CMD | OMAP_MMC_STAT_CARD_ERR  |
407 		   OMAP_MMC_STAT_END_OF_DATA;
408 	if (cmd->opcode == MMC_ERASE)
409 		irq_mask &= ~OMAP_MMC_STAT_DATA_TOUT;
410 	OMAP_MMC_WRITE(host, IE, irq_mask);
411 	OMAP_MMC_WRITE(host, CMD, cmdreg);
412 }
413 
414 static void
415 mmc_omap_release_dma(struct mmc_omap_host *host, struct mmc_data *data,
416 		     int abort)
417 {
418 	enum dma_data_direction dma_data_dir;
419 	struct device *dev = mmc_dev(host->mmc);
420 	struct dma_chan *c;
421 
422 	if (data->flags & MMC_DATA_WRITE) {
423 		dma_data_dir = DMA_TO_DEVICE;
424 		c = host->dma_tx;
425 	} else {
426 		dma_data_dir = DMA_FROM_DEVICE;
427 		c = host->dma_rx;
428 	}
429 	if (c) {
430 		if (data->error) {
431 			dmaengine_terminate_all(c);
432 			/* Claim nothing transferred on error... */
433 			data->bytes_xfered = 0;
434 		}
435 		dev = c->device->dev;
436 	}
437 	dma_unmap_sg(dev, data->sg, host->sg_len, dma_data_dir);
438 }
439 
440 static void mmc_omap_send_stop_work(struct work_struct *work)
441 {
442 	struct mmc_omap_host *host = container_of(work, struct mmc_omap_host,
443 						  send_stop_work);
444 	struct mmc_omap_slot *slot = host->current_slot;
445 	struct mmc_data *data = host->stop_data;
446 	unsigned long tick_ns;
447 
448 	tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, slot->fclk_freq);
449 	ndelay(8*tick_ns);
450 
451 	mmc_omap_start_command(host, data->stop);
452 }
453 
454 static void
455 mmc_omap_xfer_done(struct mmc_omap_host *host, struct mmc_data *data)
456 {
457 	if (host->dma_in_use)
458 		mmc_omap_release_dma(host, data, data->error);
459 
460 	host->data = NULL;
461 	host->sg_len = 0;
462 
463 	/* NOTE:  MMC layer will sometimes poll-wait CMD13 next, issuing
464 	 * dozens of requests until the card finishes writing data.
465 	 * It'd be cheaper to just wait till an EOFB interrupt arrives...
466 	 */
467 
468 	if (!data->stop) {
469 		struct mmc_host *mmc;
470 
471 		host->mrq = NULL;
472 		mmc = host->mmc;
473 		mmc_omap_release_slot(host->current_slot, 1);
474 		mmc_request_done(mmc, data->mrq);
475 		return;
476 	}
477 
478 	host->stop_data = data;
479 	queue_work(host->mmc_omap_wq, &host->send_stop_work);
480 }
481 
482 static void
483 mmc_omap_send_abort(struct mmc_omap_host *host, int maxloops)
484 {
485 	struct mmc_omap_slot *slot = host->current_slot;
486 	unsigned int restarts, passes, timeout;
487 	u16 stat = 0;
488 
489 	/* Sending abort takes 80 clocks. Have some extra and round up */
490 	timeout = DIV_ROUND_UP(120 * USEC_PER_SEC, slot->fclk_freq);
491 	restarts = 0;
492 	while (restarts < maxloops) {
493 		OMAP_MMC_WRITE(host, STAT, 0xFFFF);
494 		OMAP_MMC_WRITE(host, CMD, (3 << 12) | (1 << 7));
495 
496 		passes = 0;
497 		while (passes < timeout) {
498 			stat = OMAP_MMC_READ(host, STAT);
499 			if (stat & OMAP_MMC_STAT_END_OF_CMD)
500 				goto out;
501 			udelay(1);
502 			passes++;
503 		}
504 
505 		restarts++;
506 	}
507 out:
508 	OMAP_MMC_WRITE(host, STAT, stat);
509 }
510 
511 static void
512 mmc_omap_abort_xfer(struct mmc_omap_host *host, struct mmc_data *data)
513 {
514 	if (host->dma_in_use)
515 		mmc_omap_release_dma(host, data, 1);
516 
517 	host->data = NULL;
518 	host->sg_len = 0;
519 
520 	mmc_omap_send_abort(host, 10000);
521 }
522 
523 static void
524 mmc_omap_end_of_data(struct mmc_omap_host *host, struct mmc_data *data)
525 {
526 	unsigned long flags;
527 	int done;
528 
529 	if (!host->dma_in_use) {
530 		mmc_omap_xfer_done(host, data);
531 		return;
532 	}
533 	done = 0;
534 	spin_lock_irqsave(&host->dma_lock, flags);
535 	if (host->dma_done)
536 		done = 1;
537 	else
538 		host->brs_received = 1;
539 	spin_unlock_irqrestore(&host->dma_lock, flags);
540 	if (done)
541 		mmc_omap_xfer_done(host, data);
542 }
543 
544 static void
545 mmc_omap_dma_done(struct mmc_omap_host *host, struct mmc_data *data)
546 {
547 	unsigned long flags;
548 	int done;
549 
550 	done = 0;
551 	spin_lock_irqsave(&host->dma_lock, flags);
552 	if (host->brs_received)
553 		done = 1;
554 	else
555 		host->dma_done = 1;
556 	spin_unlock_irqrestore(&host->dma_lock, flags);
557 	if (done)
558 		mmc_omap_xfer_done(host, data);
559 }
560 
561 static void
562 mmc_omap_cmd_done(struct mmc_omap_host *host, struct mmc_command *cmd)
563 {
564 	host->cmd = NULL;
565 
566 	del_timer(&host->cmd_abort_timer);
567 
568 	if (cmd->flags & MMC_RSP_PRESENT) {
569 		if (cmd->flags & MMC_RSP_136) {
570 			/* response type 2 */
571 			cmd->resp[3] =
572 				OMAP_MMC_READ(host, RSP0) |
573 				(OMAP_MMC_READ(host, RSP1) << 16);
574 			cmd->resp[2] =
575 				OMAP_MMC_READ(host, RSP2) |
576 				(OMAP_MMC_READ(host, RSP3) << 16);
577 			cmd->resp[1] =
578 				OMAP_MMC_READ(host, RSP4) |
579 				(OMAP_MMC_READ(host, RSP5) << 16);
580 			cmd->resp[0] =
581 				OMAP_MMC_READ(host, RSP6) |
582 				(OMAP_MMC_READ(host, RSP7) << 16);
583 		} else {
584 			/* response types 1, 1b, 3, 4, 5, 6 */
585 			cmd->resp[0] =
586 				OMAP_MMC_READ(host, RSP6) |
587 				(OMAP_MMC_READ(host, RSP7) << 16);
588 		}
589 	}
590 
591 	if (host->data == NULL || cmd->error) {
592 		struct mmc_host *mmc;
593 
594 		if (host->data != NULL)
595 			mmc_omap_abort_xfer(host, host->data);
596 		host->mrq = NULL;
597 		mmc = host->mmc;
598 		mmc_omap_release_slot(host->current_slot, 1);
599 		mmc_request_done(mmc, cmd->mrq);
600 	}
601 }
602 
603 /*
604  * Abort stuck command. Can occur when card is removed while it is being
605  * read.
606  */
607 static void mmc_omap_abort_command(struct work_struct *work)
608 {
609 	struct mmc_omap_host *host = container_of(work, struct mmc_omap_host,
610 						  cmd_abort_work);
611 	BUG_ON(!host->cmd);
612 
613 	dev_dbg(mmc_dev(host->mmc), "Aborting stuck command CMD%d\n",
614 		host->cmd->opcode);
615 
616 	if (host->cmd->error == 0)
617 		host->cmd->error = -ETIMEDOUT;
618 
619 	if (host->data == NULL) {
620 		struct mmc_command *cmd;
621 		struct mmc_host    *mmc;
622 
623 		cmd = host->cmd;
624 		host->cmd = NULL;
625 		mmc_omap_send_abort(host, 10000);
626 
627 		host->mrq = NULL;
628 		mmc = host->mmc;
629 		mmc_omap_release_slot(host->current_slot, 1);
630 		mmc_request_done(mmc, cmd->mrq);
631 	} else
632 		mmc_omap_cmd_done(host, host->cmd);
633 
634 	host->abort = 0;
635 	enable_irq(host->irq);
636 }
637 
638 static void
639 mmc_omap_cmd_timer(struct timer_list *t)
640 {
641 	struct mmc_omap_host *host = from_timer(host, t, cmd_abort_timer);
642 	unsigned long flags;
643 
644 	spin_lock_irqsave(&host->slot_lock, flags);
645 	if (host->cmd != NULL && !host->abort) {
646 		OMAP_MMC_WRITE(host, IE, 0);
647 		disable_irq(host->irq);
648 		host->abort = 1;
649 		queue_work(host->mmc_omap_wq, &host->cmd_abort_work);
650 	}
651 	spin_unlock_irqrestore(&host->slot_lock, flags);
652 }
653 
654 /* PIO only */
655 static void
656 mmc_omap_sg_to_buf(struct mmc_omap_host *host)
657 {
658 	struct scatterlist *sg;
659 
660 	sg = host->data->sg + host->sg_idx;
661 	host->buffer_bytes_left = sg->length;
662 	host->buffer = sg_virt(sg);
663 	if (host->buffer_bytes_left > host->total_bytes_left)
664 		host->buffer_bytes_left = host->total_bytes_left;
665 }
666 
667 static void
668 mmc_omap_clk_timer(struct timer_list *t)
669 {
670 	struct mmc_omap_host *host = from_timer(host, t, clk_timer);
671 
672 	mmc_omap_fclk_enable(host, 0);
673 }
674 
675 /* PIO only */
676 static void
677 mmc_omap_xfer_data(struct mmc_omap_host *host, int write)
678 {
679 	int n, nwords;
680 
681 	if (host->buffer_bytes_left == 0) {
682 		host->sg_idx++;
683 		BUG_ON(host->sg_idx == host->sg_len);
684 		mmc_omap_sg_to_buf(host);
685 	}
686 	n = 64;
687 	if (n > host->buffer_bytes_left)
688 		n = host->buffer_bytes_left;
689 
690 	/* Round up to handle odd number of bytes to transfer */
691 	nwords = DIV_ROUND_UP(n, 2);
692 
693 	host->buffer_bytes_left -= n;
694 	host->total_bytes_left -= n;
695 	host->data->bytes_xfered += n;
696 
697 	if (write) {
698 		__raw_writesw(host->virt_base + OMAP_MMC_REG(host, DATA),
699 			      host->buffer, nwords);
700 	} else {
701 		__raw_readsw(host->virt_base + OMAP_MMC_REG(host, DATA),
702 			     host->buffer, nwords);
703 	}
704 
705 	host->buffer += nwords;
706 }
707 
708 #ifdef CONFIG_MMC_DEBUG
709 static void mmc_omap_report_irq(struct mmc_omap_host *host, u16 status)
710 {
711 	static const char *mmc_omap_status_bits[] = {
712 		"EOC", "CD", "CB", "BRS", "EOFB", "DTO", "DCRC", "CTO",
713 		"CCRC", "CRW", "AF", "AE", "OCRB", "CIRQ", "CERR"
714 	};
715 	int i;
716 	char res[64], *buf = res;
717 
718 	buf += sprintf(buf, "MMC IRQ 0x%x:", status);
719 
720 	for (i = 0; i < ARRAY_SIZE(mmc_omap_status_bits); i++)
721 		if (status & (1 << i))
722 			buf += sprintf(buf, " %s", mmc_omap_status_bits[i]);
723 	dev_vdbg(mmc_dev(host->mmc), "%s\n", res);
724 }
725 #else
726 static void mmc_omap_report_irq(struct mmc_omap_host *host, u16 status)
727 {
728 }
729 #endif
730 
731 
732 static irqreturn_t mmc_omap_irq(int irq, void *dev_id)
733 {
734 	struct mmc_omap_host * host = (struct mmc_omap_host *)dev_id;
735 	u16 status;
736 	int end_command;
737 	int end_transfer;
738 	int transfer_error, cmd_error;
739 
740 	if (host->cmd == NULL && host->data == NULL) {
741 		status = OMAP_MMC_READ(host, STAT);
742 		dev_info(mmc_dev(host->slots[0]->mmc),
743 			 "Spurious IRQ 0x%04x\n", status);
744 		if (status != 0) {
745 			OMAP_MMC_WRITE(host, STAT, status);
746 			OMAP_MMC_WRITE(host, IE, 0);
747 		}
748 		return IRQ_HANDLED;
749 	}
750 
751 	end_command = 0;
752 	end_transfer = 0;
753 	transfer_error = 0;
754 	cmd_error = 0;
755 
756 	while ((status = OMAP_MMC_READ(host, STAT)) != 0) {
757 		int cmd;
758 
759 		OMAP_MMC_WRITE(host, STAT, status);
760 		if (host->cmd != NULL)
761 			cmd = host->cmd->opcode;
762 		else
763 			cmd = -1;
764 		dev_dbg(mmc_dev(host->mmc), "MMC IRQ %04x (CMD %d): ",
765 			status, cmd);
766 		mmc_omap_report_irq(host, status);
767 
768 		if (host->total_bytes_left) {
769 			if ((status & OMAP_MMC_STAT_A_FULL) ||
770 			    (status & OMAP_MMC_STAT_END_OF_DATA))
771 				mmc_omap_xfer_data(host, 0);
772 			if (status & OMAP_MMC_STAT_A_EMPTY)
773 				mmc_omap_xfer_data(host, 1);
774 		}
775 
776 		if (status & OMAP_MMC_STAT_END_OF_DATA)
777 			end_transfer = 1;
778 
779 		if (status & OMAP_MMC_STAT_DATA_TOUT) {
780 			dev_dbg(mmc_dev(host->mmc), "data timeout (CMD%d)\n",
781 				cmd);
782 			if (host->data) {
783 				host->data->error = -ETIMEDOUT;
784 				transfer_error = 1;
785 			}
786 		}
787 
788 		if (status & OMAP_MMC_STAT_DATA_CRC) {
789 			if (host->data) {
790 				host->data->error = -EILSEQ;
791 				dev_dbg(mmc_dev(host->mmc),
792 					 "data CRC error, bytes left %d\n",
793 					host->total_bytes_left);
794 				transfer_error = 1;
795 			} else {
796 				dev_dbg(mmc_dev(host->mmc), "data CRC error\n");
797 			}
798 		}
799 
800 		if (status & OMAP_MMC_STAT_CMD_TOUT) {
801 			/* Timeouts are routine with some commands */
802 			if (host->cmd) {
803 				struct mmc_omap_slot *slot =
804 					host->current_slot;
805 				if (slot == NULL ||
806 				    !mmc_omap_cover_is_open(slot))
807 					dev_err(mmc_dev(host->mmc),
808 						"command timeout (CMD%d)\n",
809 						cmd);
810 				host->cmd->error = -ETIMEDOUT;
811 				end_command = 1;
812 				cmd_error = 1;
813 			}
814 		}
815 
816 		if (status & OMAP_MMC_STAT_CMD_CRC) {
817 			if (host->cmd) {
818 				dev_err(mmc_dev(host->mmc),
819 					"command CRC error (CMD%d, arg 0x%08x)\n",
820 					cmd, host->cmd->arg);
821 				host->cmd->error = -EILSEQ;
822 				end_command = 1;
823 				cmd_error = 1;
824 			} else
825 				dev_err(mmc_dev(host->mmc),
826 					"command CRC error without cmd?\n");
827 		}
828 
829 		if (status & OMAP_MMC_STAT_CARD_ERR) {
830 			dev_dbg(mmc_dev(host->mmc),
831 				"ignoring card status error (CMD%d)\n",
832 				cmd);
833 			end_command = 1;
834 		}
835 
836 		/*
837 		 * NOTE: On 1610 the END_OF_CMD may come too early when
838 		 * starting a write
839 		 */
840 		if ((status & OMAP_MMC_STAT_END_OF_CMD) &&
841 		    (!(status & OMAP_MMC_STAT_A_EMPTY))) {
842 			end_command = 1;
843 		}
844 	}
845 
846 	if (cmd_error && host->data) {
847 		del_timer(&host->cmd_abort_timer);
848 		host->abort = 1;
849 		OMAP_MMC_WRITE(host, IE, 0);
850 		disable_irq_nosync(host->irq);
851 		queue_work(host->mmc_omap_wq, &host->cmd_abort_work);
852 		return IRQ_HANDLED;
853 	}
854 
855 	if (end_command && host->cmd)
856 		mmc_omap_cmd_done(host, host->cmd);
857 	if (host->data != NULL) {
858 		if (transfer_error)
859 			mmc_omap_xfer_done(host, host->data);
860 		else if (end_transfer)
861 			mmc_omap_end_of_data(host, host->data);
862 	}
863 
864 	return IRQ_HANDLED;
865 }
866 
867 void omap_mmc_notify_cover_event(struct device *dev, int num, int is_closed)
868 {
869 	int cover_open;
870 	struct mmc_omap_host *host = dev_get_drvdata(dev);
871 	struct mmc_omap_slot *slot = host->slots[num];
872 
873 	BUG_ON(num >= host->nr_slots);
874 
875 	/* Other subsystems can call in here before we're initialised. */
876 	if (host->nr_slots == 0 || !host->slots[num])
877 		return;
878 
879 	cover_open = mmc_omap_cover_is_open(slot);
880 	if (cover_open != slot->cover_open) {
881 		slot->cover_open = cover_open;
882 		sysfs_notify(&slot->mmc->class_dev.kobj, NULL, "cover_switch");
883 	}
884 
885 	tasklet_hi_schedule(&slot->cover_tasklet);
886 }
887 
888 static void mmc_omap_cover_timer(struct timer_list *t)
889 {
890 	struct mmc_omap_slot *slot = from_timer(slot, t, cover_timer);
891 	tasklet_schedule(&slot->cover_tasklet);
892 }
893 
894 static void mmc_omap_cover_handler(struct tasklet_struct *t)
895 {
896 	struct mmc_omap_slot *slot = from_tasklet(slot, t, cover_tasklet);
897 	int cover_open = mmc_omap_cover_is_open(slot);
898 
899 	mmc_detect_change(slot->mmc, 0);
900 	if (!cover_open)
901 		return;
902 
903 	/*
904 	 * If no card is inserted, we postpone polling until
905 	 * the cover has been closed.
906 	 */
907 	if (slot->mmc->card == NULL)
908 		return;
909 
910 	mod_timer(&slot->cover_timer,
911 		  jiffies + msecs_to_jiffies(OMAP_MMC_COVER_POLL_DELAY));
912 }
913 
914 static void mmc_omap_dma_callback(void *priv)
915 {
916 	struct mmc_omap_host *host = priv;
917 	struct mmc_data *data = host->data;
918 
919 	/* If we got to the end of DMA, assume everything went well */
920 	data->bytes_xfered += data->blocks * data->blksz;
921 
922 	mmc_omap_dma_done(host, data);
923 }
924 
925 static inline void set_cmd_timeout(struct mmc_omap_host *host, struct mmc_request *req)
926 {
927 	u16 reg;
928 
929 	reg = OMAP_MMC_READ(host, SDIO);
930 	reg &= ~(1 << 5);
931 	OMAP_MMC_WRITE(host, SDIO, reg);
932 	/* Set maximum timeout */
933 	OMAP_MMC_WRITE(host, CTO, 0xfd);
934 }
935 
936 static inline void set_data_timeout(struct mmc_omap_host *host, struct mmc_request *req)
937 {
938 	unsigned int timeout, cycle_ns;
939 	u16 reg;
940 
941 	cycle_ns = 1000000000 / host->current_slot->fclk_freq;
942 	timeout = req->data->timeout_ns / cycle_ns;
943 	timeout += req->data->timeout_clks;
944 
945 	/* Check if we need to use timeout multiplier register */
946 	reg = OMAP_MMC_READ(host, SDIO);
947 	if (timeout > 0xffff) {
948 		reg |= (1 << 5);
949 		timeout /= 1024;
950 	} else
951 		reg &= ~(1 << 5);
952 	OMAP_MMC_WRITE(host, SDIO, reg);
953 	OMAP_MMC_WRITE(host, DTO, timeout);
954 }
955 
956 static void
957 mmc_omap_prepare_data(struct mmc_omap_host *host, struct mmc_request *req)
958 {
959 	struct mmc_data *data = req->data;
960 	int i, use_dma = 1, block_size;
961 	struct scatterlist *sg;
962 	unsigned sg_len;
963 
964 	host->data = data;
965 	if (data == NULL) {
966 		OMAP_MMC_WRITE(host, BLEN, 0);
967 		OMAP_MMC_WRITE(host, NBLK, 0);
968 		OMAP_MMC_WRITE(host, BUF, 0);
969 		host->dma_in_use = 0;
970 		set_cmd_timeout(host, req);
971 		return;
972 	}
973 
974 	block_size = data->blksz;
975 
976 	OMAP_MMC_WRITE(host, NBLK, data->blocks - 1);
977 	OMAP_MMC_WRITE(host, BLEN, block_size - 1);
978 	set_data_timeout(host, req);
979 
980 	/* cope with calling layer confusion; it issues "single
981 	 * block" writes using multi-block scatterlists.
982 	 */
983 	sg_len = (data->blocks == 1) ? 1 : data->sg_len;
984 
985 	/* Only do DMA for entire blocks */
986 	for_each_sg(data->sg, sg, sg_len, i) {
987 		if ((sg->length % block_size) != 0) {
988 			use_dma = 0;
989 			break;
990 		}
991 	}
992 
993 	host->sg_idx = 0;
994 	if (use_dma) {
995 		enum dma_data_direction dma_data_dir;
996 		struct dma_async_tx_descriptor *tx;
997 		struct dma_chan *c;
998 		u32 burst, *bp;
999 		u16 buf;
1000 
1001 		/*
1002 		 * FIFO is 16x2 bytes on 15xx, and 32x2 bytes on 16xx
1003 		 * and 24xx. Use 16 or 32 word frames when the
1004 		 * blocksize is at least that large. Blocksize is
1005 		 * usually 512 bytes; but not for some SD reads.
1006 		 */
1007 		burst = mmc_omap15xx() ? 32 : 64;
1008 		if (burst > data->blksz)
1009 			burst = data->blksz;
1010 
1011 		burst >>= 1;
1012 
1013 		if (data->flags & MMC_DATA_WRITE) {
1014 			c = host->dma_tx;
1015 			bp = &host->dma_tx_burst;
1016 			buf = 0x0f80 | (burst - 1) << 0;
1017 			dma_data_dir = DMA_TO_DEVICE;
1018 		} else {
1019 			c = host->dma_rx;
1020 			bp = &host->dma_rx_burst;
1021 			buf = 0x800f | (burst - 1) << 8;
1022 			dma_data_dir = DMA_FROM_DEVICE;
1023 		}
1024 
1025 		if (!c)
1026 			goto use_pio;
1027 
1028 		/* Only reconfigure if we have a different burst size */
1029 		if (*bp != burst) {
1030 			struct dma_slave_config cfg = {
1031 				.src_addr = host->phys_base +
1032 					    OMAP_MMC_REG(host, DATA),
1033 				.dst_addr = host->phys_base +
1034 					    OMAP_MMC_REG(host, DATA),
1035 				.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES,
1036 				.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES,
1037 				.src_maxburst = burst,
1038 				.dst_maxburst = burst,
1039 			};
1040 
1041 			if (dmaengine_slave_config(c, &cfg))
1042 				goto use_pio;
1043 
1044 			*bp = burst;
1045 		}
1046 
1047 		host->sg_len = dma_map_sg(c->device->dev, data->sg, sg_len,
1048 					  dma_data_dir);
1049 		if (host->sg_len == 0)
1050 			goto use_pio;
1051 
1052 		tx = dmaengine_prep_slave_sg(c, data->sg, host->sg_len,
1053 			data->flags & MMC_DATA_WRITE ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM,
1054 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1055 		if (!tx)
1056 			goto use_pio;
1057 
1058 		OMAP_MMC_WRITE(host, BUF, buf);
1059 
1060 		tx->callback = mmc_omap_dma_callback;
1061 		tx->callback_param = host;
1062 		dmaengine_submit(tx);
1063 		host->brs_received = 0;
1064 		host->dma_done = 0;
1065 		host->dma_in_use = 1;
1066 		return;
1067 	}
1068  use_pio:
1069 
1070 	/* Revert to PIO? */
1071 	OMAP_MMC_WRITE(host, BUF, 0x1f1f);
1072 	host->total_bytes_left = data->blocks * block_size;
1073 	host->sg_len = sg_len;
1074 	mmc_omap_sg_to_buf(host);
1075 	host->dma_in_use = 0;
1076 }
1077 
1078 static void mmc_omap_start_request(struct mmc_omap_host *host,
1079 				   struct mmc_request *req)
1080 {
1081 	BUG_ON(host->mrq != NULL);
1082 
1083 	host->mrq = req;
1084 
1085 	/* only touch fifo AFTER the controller readies it */
1086 	mmc_omap_prepare_data(host, req);
1087 	mmc_omap_start_command(host, req->cmd);
1088 	if (host->dma_in_use) {
1089 		struct dma_chan *c = host->data->flags & MMC_DATA_WRITE ?
1090 				host->dma_tx : host->dma_rx;
1091 
1092 		dma_async_issue_pending(c);
1093 	}
1094 }
1095 
1096 static void mmc_omap_request(struct mmc_host *mmc, struct mmc_request *req)
1097 {
1098 	struct mmc_omap_slot *slot = mmc_priv(mmc);
1099 	struct mmc_omap_host *host = slot->host;
1100 	unsigned long flags;
1101 
1102 	spin_lock_irqsave(&host->slot_lock, flags);
1103 	if (host->mmc != NULL) {
1104 		BUG_ON(slot->mrq != NULL);
1105 		slot->mrq = req;
1106 		spin_unlock_irqrestore(&host->slot_lock, flags);
1107 		return;
1108 	} else
1109 		host->mmc = mmc;
1110 	spin_unlock_irqrestore(&host->slot_lock, flags);
1111 	mmc_omap_select_slot(slot, 1);
1112 	mmc_omap_start_request(host, req);
1113 }
1114 
1115 static void mmc_omap_set_power(struct mmc_omap_slot *slot, int power_on,
1116 				int vdd)
1117 {
1118 	struct mmc_omap_host *host;
1119 
1120 	host = slot->host;
1121 
1122 	if (slot->vsd)
1123 		gpiod_set_value(slot->vsd, power_on);
1124 	if (slot->vio)
1125 		gpiod_set_value(slot->vio, power_on);
1126 
1127 	if (slot->pdata->set_power != NULL)
1128 		slot->pdata->set_power(mmc_dev(slot->mmc), slot->id, power_on,
1129 					vdd);
1130 	if (mmc_omap2()) {
1131 		u16 w;
1132 
1133 		if (power_on) {
1134 			w = OMAP_MMC_READ(host, CON);
1135 			OMAP_MMC_WRITE(host, CON, w | (1 << 11));
1136 		} else {
1137 			w = OMAP_MMC_READ(host, CON);
1138 			OMAP_MMC_WRITE(host, CON, w & ~(1 << 11));
1139 		}
1140 	}
1141 }
1142 
1143 static int mmc_omap_calc_divisor(struct mmc_host *mmc, struct mmc_ios *ios)
1144 {
1145 	struct mmc_omap_slot *slot = mmc_priv(mmc);
1146 	struct mmc_omap_host *host = slot->host;
1147 	int func_clk_rate = clk_get_rate(host->fclk);
1148 	int dsor;
1149 
1150 	if (ios->clock == 0)
1151 		return 0;
1152 
1153 	dsor = func_clk_rate / ios->clock;
1154 	if (dsor < 1)
1155 		dsor = 1;
1156 
1157 	if (func_clk_rate / dsor > ios->clock)
1158 		dsor++;
1159 
1160 	if (dsor > 250)
1161 		dsor = 250;
1162 
1163 	slot->fclk_freq = func_clk_rate / dsor;
1164 
1165 	if (ios->bus_width == MMC_BUS_WIDTH_4)
1166 		dsor |= 1 << 15;
1167 
1168 	return dsor;
1169 }
1170 
1171 static void mmc_omap_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
1172 {
1173 	struct mmc_omap_slot *slot = mmc_priv(mmc);
1174 	struct mmc_omap_host *host = slot->host;
1175 	int i, dsor;
1176 	int clk_enabled, init_stream;
1177 
1178 	mmc_omap_select_slot(slot, 0);
1179 
1180 	dsor = mmc_omap_calc_divisor(mmc, ios);
1181 
1182 	if (ios->vdd != slot->vdd)
1183 		slot->vdd = ios->vdd;
1184 
1185 	clk_enabled = 0;
1186 	init_stream = 0;
1187 	switch (ios->power_mode) {
1188 	case MMC_POWER_OFF:
1189 		mmc_omap_set_power(slot, 0, ios->vdd);
1190 		break;
1191 	case MMC_POWER_UP:
1192 		/* Cannot touch dsor yet, just power up MMC */
1193 		mmc_omap_set_power(slot, 1, ios->vdd);
1194 		slot->power_mode = ios->power_mode;
1195 		goto exit;
1196 	case MMC_POWER_ON:
1197 		mmc_omap_fclk_enable(host, 1);
1198 		clk_enabled = 1;
1199 		dsor |= 1 << 11;
1200 		if (slot->power_mode != MMC_POWER_ON)
1201 			init_stream = 1;
1202 		break;
1203 	}
1204 	slot->power_mode = ios->power_mode;
1205 
1206 	if (slot->bus_mode != ios->bus_mode) {
1207 		if (slot->pdata->set_bus_mode != NULL)
1208 			slot->pdata->set_bus_mode(mmc_dev(mmc), slot->id,
1209 						  ios->bus_mode);
1210 		slot->bus_mode = ios->bus_mode;
1211 	}
1212 
1213 	/* On insanely high arm_per frequencies something sometimes
1214 	 * goes somehow out of sync, and the POW bit is not being set,
1215 	 * which results in the while loop below getting stuck.
1216 	 * Writing to the CON register twice seems to do the trick. */
1217 	for (i = 0; i < 2; i++)
1218 		OMAP_MMC_WRITE(host, CON, dsor);
1219 	slot->saved_con = dsor;
1220 	if (init_stream) {
1221 		/* worst case at 400kHz, 80 cycles makes 200 microsecs */
1222 		int usecs = 250;
1223 
1224 		/* Send clock cycles, poll completion */
1225 		OMAP_MMC_WRITE(host, IE, 0);
1226 		OMAP_MMC_WRITE(host, STAT, 0xffff);
1227 		OMAP_MMC_WRITE(host, CMD, 1 << 7);
1228 		while (usecs > 0 && (OMAP_MMC_READ(host, STAT) & 1) == 0) {
1229 			udelay(1);
1230 			usecs--;
1231 		}
1232 		OMAP_MMC_WRITE(host, STAT, 1);
1233 	}
1234 
1235 exit:
1236 	mmc_omap_release_slot(slot, clk_enabled);
1237 }
1238 
1239 static const struct mmc_host_ops mmc_omap_ops = {
1240 	.request	= mmc_omap_request,
1241 	.set_ios	= mmc_omap_set_ios,
1242 };
1243 
1244 static int mmc_omap_new_slot(struct mmc_omap_host *host, int id)
1245 {
1246 	struct mmc_omap_slot *slot = NULL;
1247 	struct mmc_host *mmc;
1248 	int r;
1249 
1250 	mmc = mmc_alloc_host(sizeof(struct mmc_omap_slot), host->dev);
1251 	if (mmc == NULL)
1252 		return -ENOMEM;
1253 
1254 	slot = mmc_priv(mmc);
1255 	slot->host = host;
1256 	slot->mmc = mmc;
1257 	slot->id = id;
1258 	slot->power_mode = MMC_POWER_UNDEFINED;
1259 	slot->pdata = &host->pdata->slots[id];
1260 
1261 	/* Check for some optional GPIO controls */
1262 	slot->vsd = gpiod_get_index_optional(host->dev, "vsd",
1263 					     id, GPIOD_OUT_LOW);
1264 	if (IS_ERR(slot->vsd))
1265 		return dev_err_probe(host->dev, PTR_ERR(slot->vsd),
1266 				     "error looking up VSD GPIO\n");
1267 	slot->vio = gpiod_get_index_optional(host->dev, "vio",
1268 					     id, GPIOD_OUT_LOW);
1269 	if (IS_ERR(slot->vio))
1270 		return dev_err_probe(host->dev, PTR_ERR(slot->vio),
1271 				     "error looking up VIO GPIO\n");
1272 	slot->cover = gpiod_get_index_optional(host->dev, "cover",
1273 						id, GPIOD_IN);
1274 	if (IS_ERR(slot->cover))
1275 		return dev_err_probe(host->dev, PTR_ERR(slot->cover),
1276 				     "error looking up cover switch GPIO\n");
1277 
1278 	host->slots[id] = slot;
1279 
1280 	mmc->caps = 0;
1281 	if (host->pdata->slots[id].wires >= 4)
1282 		mmc->caps |= MMC_CAP_4_BIT_DATA;
1283 
1284 	mmc->ops = &mmc_omap_ops;
1285 	mmc->f_min = 400000;
1286 
1287 	if (mmc_omap2())
1288 		mmc->f_max = 48000000;
1289 	else
1290 		mmc->f_max = 24000000;
1291 	if (host->pdata->max_freq)
1292 		mmc->f_max = min(host->pdata->max_freq, mmc->f_max);
1293 	mmc->ocr_avail = slot->pdata->ocr_mask;
1294 
1295 	/* Use scatterlist DMA to reduce per-transfer costs.
1296 	 * NOTE max_seg_size assumption that small blocks aren't
1297 	 * normally used (except e.g. for reading SD registers).
1298 	 */
1299 	mmc->max_segs = 32;
1300 	mmc->max_blk_size = 2048;	/* BLEN is 11 bits (+1) */
1301 	mmc->max_blk_count = 2048;	/* NBLK is 11 bits (+1) */
1302 	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
1303 	mmc->max_seg_size = mmc->max_req_size;
1304 
1305 	if (slot->pdata->get_cover_state != NULL) {
1306 		timer_setup(&slot->cover_timer, mmc_omap_cover_timer, 0);
1307 		tasklet_setup(&slot->cover_tasklet, mmc_omap_cover_handler);
1308 	}
1309 
1310 	r = mmc_add_host(mmc);
1311 	if (r < 0)
1312 		goto err_remove_host;
1313 
1314 	if (slot->pdata->name != NULL) {
1315 		r = device_create_file(&mmc->class_dev,
1316 					&dev_attr_slot_name);
1317 		if (r < 0)
1318 			goto err_remove_host;
1319 	}
1320 
1321 	if (slot->pdata->get_cover_state != NULL) {
1322 		r = device_create_file(&mmc->class_dev,
1323 					&dev_attr_cover_switch);
1324 		if (r < 0)
1325 			goto err_remove_slot_name;
1326 		tasklet_schedule(&slot->cover_tasklet);
1327 	}
1328 
1329 	return 0;
1330 
1331 err_remove_slot_name:
1332 	if (slot->pdata->name != NULL)
1333 		device_remove_file(&mmc->class_dev, &dev_attr_slot_name);
1334 err_remove_host:
1335 	mmc_remove_host(mmc);
1336 	mmc_free_host(mmc);
1337 	return r;
1338 }
1339 
1340 static void mmc_omap_remove_slot(struct mmc_omap_slot *slot)
1341 {
1342 	struct mmc_host *mmc = slot->mmc;
1343 
1344 	if (slot->pdata->name != NULL)
1345 		device_remove_file(&mmc->class_dev, &dev_attr_slot_name);
1346 	if (slot->pdata->get_cover_state != NULL)
1347 		device_remove_file(&mmc->class_dev, &dev_attr_cover_switch);
1348 
1349 	tasklet_kill(&slot->cover_tasklet);
1350 	del_timer_sync(&slot->cover_timer);
1351 	flush_workqueue(slot->host->mmc_omap_wq);
1352 
1353 	mmc_remove_host(mmc);
1354 	mmc_free_host(mmc);
1355 }
1356 
1357 static int mmc_omap_probe(struct platform_device *pdev)
1358 {
1359 	struct omap_mmc_platform_data *pdata = pdev->dev.platform_data;
1360 	struct mmc_omap_host *host = NULL;
1361 	struct resource *res;
1362 	int i, ret = 0;
1363 	int irq;
1364 
1365 	if (pdata == NULL) {
1366 		dev_err(&pdev->dev, "platform data missing\n");
1367 		return -ENXIO;
1368 	}
1369 	if (pdata->nr_slots == 0) {
1370 		dev_err(&pdev->dev, "no slots\n");
1371 		return -EPROBE_DEFER;
1372 	}
1373 
1374 	host = devm_kzalloc(&pdev->dev, sizeof(struct mmc_omap_host),
1375 			    GFP_KERNEL);
1376 	if (host == NULL)
1377 		return -ENOMEM;
1378 
1379 	irq = platform_get_irq(pdev, 0);
1380 	if (irq < 0)
1381 		return irq;
1382 
1383 	host->virt_base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1384 	if (IS_ERR(host->virt_base))
1385 		return PTR_ERR(host->virt_base);
1386 
1387 	host->slot_switch = gpiod_get_optional(host->dev, "switch",
1388 					       GPIOD_OUT_LOW);
1389 	if (IS_ERR(host->slot_switch))
1390 		return dev_err_probe(host->dev, PTR_ERR(host->slot_switch),
1391 				     "error looking up slot switch GPIO\n");
1392 
1393 
1394 	INIT_WORK(&host->slot_release_work, mmc_omap_slot_release_work);
1395 	INIT_WORK(&host->send_stop_work, mmc_omap_send_stop_work);
1396 
1397 	INIT_WORK(&host->cmd_abort_work, mmc_omap_abort_command);
1398 	timer_setup(&host->cmd_abort_timer, mmc_omap_cmd_timer, 0);
1399 
1400 	spin_lock_init(&host->clk_lock);
1401 	timer_setup(&host->clk_timer, mmc_omap_clk_timer, 0);
1402 
1403 	spin_lock_init(&host->dma_lock);
1404 	spin_lock_init(&host->slot_lock);
1405 	init_waitqueue_head(&host->slot_wq);
1406 
1407 	host->pdata = pdata;
1408 	host->features = host->pdata->slots[0].features;
1409 	host->dev = &pdev->dev;
1410 	platform_set_drvdata(pdev, host);
1411 
1412 	host->id = pdev->id;
1413 	host->irq = irq;
1414 	host->phys_base = res->start;
1415 	host->iclk = clk_get(&pdev->dev, "ick");
1416 	if (IS_ERR(host->iclk))
1417 		return PTR_ERR(host->iclk);
1418 	clk_prepare_enable(host->iclk);
1419 
1420 	host->fclk = clk_get(&pdev->dev, "fck");
1421 	if (IS_ERR(host->fclk)) {
1422 		ret = PTR_ERR(host->fclk);
1423 		goto err_free_iclk;
1424 	}
1425 
1426 	ret = clk_prepare(host->fclk);
1427 	if (ret)
1428 		goto err_put_fclk;
1429 
1430 	host->dma_tx_burst = -1;
1431 	host->dma_rx_burst = -1;
1432 
1433 	host->dma_tx = dma_request_chan(&pdev->dev, "tx");
1434 	if (IS_ERR(host->dma_tx)) {
1435 		ret = PTR_ERR(host->dma_tx);
1436 		if (ret == -EPROBE_DEFER)
1437 			goto err_free_fclk;
1438 
1439 		host->dma_tx = NULL;
1440 		dev_warn(host->dev, "TX DMA channel request failed\n");
1441 	}
1442 
1443 	host->dma_rx = dma_request_chan(&pdev->dev, "rx");
1444 	if (IS_ERR(host->dma_rx)) {
1445 		ret = PTR_ERR(host->dma_rx);
1446 		if (ret == -EPROBE_DEFER) {
1447 			if (host->dma_tx)
1448 				dma_release_channel(host->dma_tx);
1449 			goto err_free_fclk;
1450 		}
1451 
1452 		host->dma_rx = NULL;
1453 		dev_warn(host->dev, "RX DMA channel request failed\n");
1454 	}
1455 
1456 	ret = request_irq(host->irq, mmc_omap_irq, 0, DRIVER_NAME, host);
1457 	if (ret)
1458 		goto err_free_dma;
1459 
1460 	if (pdata->init != NULL) {
1461 		ret = pdata->init(&pdev->dev);
1462 		if (ret < 0)
1463 			goto err_free_irq;
1464 	}
1465 
1466 	host->nr_slots = pdata->nr_slots;
1467 	host->reg_shift = (mmc_omap7xx() ? 1 : 2);
1468 
1469 	host->mmc_omap_wq = alloc_workqueue("mmc_omap", 0, 0);
1470 	if (!host->mmc_omap_wq) {
1471 		ret = -ENOMEM;
1472 		goto err_plat_cleanup;
1473 	}
1474 
1475 	for (i = 0; i < pdata->nr_slots; i++) {
1476 		ret = mmc_omap_new_slot(host, i);
1477 		if (ret < 0) {
1478 			while (--i >= 0)
1479 				mmc_omap_remove_slot(host->slots[i]);
1480 
1481 			goto err_destroy_wq;
1482 		}
1483 	}
1484 
1485 	return 0;
1486 
1487 err_destroy_wq:
1488 	destroy_workqueue(host->mmc_omap_wq);
1489 err_plat_cleanup:
1490 	if (pdata->cleanup)
1491 		pdata->cleanup(&pdev->dev);
1492 err_free_irq:
1493 	free_irq(host->irq, host);
1494 err_free_dma:
1495 	if (host->dma_tx)
1496 		dma_release_channel(host->dma_tx);
1497 	if (host->dma_rx)
1498 		dma_release_channel(host->dma_rx);
1499 err_free_fclk:
1500 	clk_unprepare(host->fclk);
1501 err_put_fclk:
1502 	clk_put(host->fclk);
1503 err_free_iclk:
1504 	clk_disable_unprepare(host->iclk);
1505 	clk_put(host->iclk);
1506 	return ret;
1507 }
1508 
1509 static int mmc_omap_remove(struct platform_device *pdev)
1510 {
1511 	struct mmc_omap_host *host = platform_get_drvdata(pdev);
1512 	int i;
1513 
1514 	BUG_ON(host == NULL);
1515 
1516 	for (i = 0; i < host->nr_slots; i++)
1517 		mmc_omap_remove_slot(host->slots[i]);
1518 
1519 	if (host->pdata->cleanup)
1520 		host->pdata->cleanup(&pdev->dev);
1521 
1522 	mmc_omap_fclk_enable(host, 0);
1523 	free_irq(host->irq, host);
1524 	clk_unprepare(host->fclk);
1525 	clk_put(host->fclk);
1526 	clk_disable_unprepare(host->iclk);
1527 	clk_put(host->iclk);
1528 
1529 	if (host->dma_tx)
1530 		dma_release_channel(host->dma_tx);
1531 	if (host->dma_rx)
1532 		dma_release_channel(host->dma_rx);
1533 
1534 	destroy_workqueue(host->mmc_omap_wq);
1535 
1536 	return 0;
1537 }
1538 
1539 #if IS_BUILTIN(CONFIG_OF)
1540 static const struct of_device_id mmc_omap_match[] = {
1541 	{ .compatible = "ti,omap2420-mmc", },
1542 	{ },
1543 };
1544 MODULE_DEVICE_TABLE(of, mmc_omap_match);
1545 #endif
1546 
1547 static struct platform_driver mmc_omap_driver = {
1548 	.probe		= mmc_omap_probe,
1549 	.remove		= mmc_omap_remove,
1550 	.driver		= {
1551 		.name	= DRIVER_NAME,
1552 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1553 		.of_match_table = of_match_ptr(mmc_omap_match),
1554 	},
1555 };
1556 
1557 module_platform_driver(mmc_omap_driver);
1558 MODULE_DESCRIPTION("OMAP Multimedia Card driver");
1559 MODULE_LICENSE("GPL");
1560 MODULE_ALIAS("platform:" DRIVER_NAME);
1561 MODULE_AUTHOR("Juha Yrjölä");
1562