xref: /linux/drivers/mmc/host/omap.c (revision 4b660dbd9ee2059850fd30e0df420ca7a38a1856)
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 	struct sg_mapping_iter	sg_miter;
152 	unsigned int		sg_len;
153 	u32			total_bytes_left;
154 
155 	unsigned		features;
156 	unsigned		brs_received:1, dma_done:1;
157 	unsigned		dma_in_use:1;
158 	spinlock_t		dma_lock;
159 
160 	struct mmc_omap_slot    *slots[OMAP_MMC_MAX_SLOTS];
161 	struct mmc_omap_slot    *current_slot;
162 	spinlock_t              slot_lock;
163 	wait_queue_head_t       slot_wq;
164 	int                     nr_slots;
165 
166 	struct timer_list       clk_timer;
167 	spinlock_t		clk_lock;     /* for changing enabled state */
168 	unsigned int            fclk_enabled:1;
169 	struct workqueue_struct *mmc_omap_wq;
170 
171 	struct omap_mmc_platform_data *pdata;
172 };
173 
174 
175 static void mmc_omap_fclk_offdelay(struct mmc_omap_slot *slot)
176 {
177 	unsigned long tick_ns;
178 
179 	if (slot != NULL && slot->host->fclk_enabled && slot->fclk_freq > 0) {
180 		tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, slot->fclk_freq);
181 		ndelay(8 * tick_ns);
182 	}
183 }
184 
185 static void mmc_omap_fclk_enable(struct mmc_omap_host *host, unsigned int enable)
186 {
187 	unsigned long flags;
188 
189 	spin_lock_irqsave(&host->clk_lock, flags);
190 	if (host->fclk_enabled != enable) {
191 		host->fclk_enabled = enable;
192 		if (enable)
193 			clk_enable(host->fclk);
194 		else
195 			clk_disable(host->fclk);
196 	}
197 	spin_unlock_irqrestore(&host->clk_lock, flags);
198 }
199 
200 static void mmc_omap_select_slot(struct mmc_omap_slot *slot, int claimed)
201 {
202 	struct mmc_omap_host *host = slot->host;
203 	unsigned long flags;
204 
205 	if (claimed)
206 		goto no_claim;
207 	spin_lock_irqsave(&host->slot_lock, flags);
208 	while (host->mmc != NULL) {
209 		spin_unlock_irqrestore(&host->slot_lock, flags);
210 		wait_event(host->slot_wq, host->mmc == NULL);
211 		spin_lock_irqsave(&host->slot_lock, flags);
212 	}
213 	host->mmc = slot->mmc;
214 	spin_unlock_irqrestore(&host->slot_lock, flags);
215 no_claim:
216 	del_timer(&host->clk_timer);
217 	if (host->current_slot != slot || !claimed)
218 		mmc_omap_fclk_offdelay(host->current_slot);
219 
220 	if (host->current_slot != slot) {
221 		OMAP_MMC_WRITE(host, CON, slot->saved_con & 0xFC00);
222 		if (host->slot_switch)
223 			/*
224 			 * With two slots and a simple GPIO switch, setting
225 			 * the GPIO to 0 selects slot ID 0, setting it to 1
226 			 * selects slot ID 1.
227 			 */
228 			gpiod_set_value(host->slot_switch, slot->id);
229 		host->current_slot = slot;
230 	}
231 
232 	if (claimed) {
233 		mmc_omap_fclk_enable(host, 1);
234 
235 		/* Doing the dummy read here seems to work around some bug
236 		 * at least in OMAP24xx silicon where the command would not
237 		 * start after writing the CMD register. Sigh. */
238 		OMAP_MMC_READ(host, CON);
239 
240 		OMAP_MMC_WRITE(host, CON, slot->saved_con);
241 	} else
242 		mmc_omap_fclk_enable(host, 0);
243 }
244 
245 static void mmc_omap_start_request(struct mmc_omap_host *host,
246 				   struct mmc_request *req);
247 
248 static void mmc_omap_slot_release_work(struct work_struct *work)
249 {
250 	struct mmc_omap_host *host = container_of(work, struct mmc_omap_host,
251 						  slot_release_work);
252 	struct mmc_omap_slot *next_slot = host->next_slot;
253 	struct mmc_request *rq;
254 
255 	host->next_slot = NULL;
256 	mmc_omap_select_slot(next_slot, 1);
257 
258 	rq = next_slot->mrq;
259 	next_slot->mrq = NULL;
260 	mmc_omap_start_request(host, rq);
261 }
262 
263 static void mmc_omap_release_slot(struct mmc_omap_slot *slot, int clk_enabled)
264 {
265 	struct mmc_omap_host *host = slot->host;
266 	unsigned long flags;
267 	int i;
268 
269 	BUG_ON(slot == NULL || host->mmc == NULL);
270 
271 	if (clk_enabled)
272 		/* Keeps clock running for at least 8 cycles on valid freq */
273 		mod_timer(&host->clk_timer, jiffies  + HZ/10);
274 	else {
275 		del_timer(&host->clk_timer);
276 		mmc_omap_fclk_offdelay(slot);
277 		mmc_omap_fclk_enable(host, 0);
278 	}
279 
280 	spin_lock_irqsave(&host->slot_lock, flags);
281 	/* Check for any pending requests */
282 	for (i = 0; i < host->nr_slots; i++) {
283 		struct mmc_omap_slot *new_slot;
284 
285 		if (host->slots[i] == NULL || host->slots[i]->mrq == NULL)
286 			continue;
287 
288 		BUG_ON(host->next_slot != NULL);
289 		new_slot = host->slots[i];
290 		/* The current slot should not have a request in queue */
291 		BUG_ON(new_slot == host->current_slot);
292 
293 		host->next_slot = new_slot;
294 		host->mmc = new_slot->mmc;
295 		spin_unlock_irqrestore(&host->slot_lock, flags);
296 		queue_work(host->mmc_omap_wq, &host->slot_release_work);
297 		return;
298 	}
299 
300 	host->mmc = NULL;
301 	wake_up(&host->slot_wq);
302 	spin_unlock_irqrestore(&host->slot_lock, flags);
303 }
304 
305 static inline
306 int mmc_omap_cover_is_open(struct mmc_omap_slot *slot)
307 {
308 	/* If we have a GPIO then use that */
309 	if (slot->cover)
310 		return gpiod_get_value(slot->cover);
311 	if (slot->pdata->get_cover_state)
312 		return slot->pdata->get_cover_state(mmc_dev(slot->mmc),
313 						    slot->id);
314 	return 0;
315 }
316 
317 static ssize_t
318 mmc_omap_show_cover_switch(struct device *dev, struct device_attribute *attr,
319 			   char *buf)
320 {
321 	struct mmc_host *mmc = container_of(dev, struct mmc_host, class_dev);
322 	struct mmc_omap_slot *slot = mmc_priv(mmc);
323 
324 	return sprintf(buf, "%s\n", mmc_omap_cover_is_open(slot) ? "open" :
325 		       "closed");
326 }
327 
328 static DEVICE_ATTR(cover_switch, S_IRUGO, mmc_omap_show_cover_switch, NULL);
329 
330 static ssize_t
331 mmc_omap_show_slot_name(struct device *dev, struct device_attribute *attr,
332 			char *buf)
333 {
334 	struct mmc_host *mmc = container_of(dev, struct mmc_host, class_dev);
335 	struct mmc_omap_slot *slot = mmc_priv(mmc);
336 
337 	return sprintf(buf, "%s\n", slot->pdata->name);
338 }
339 
340 static DEVICE_ATTR(slot_name, S_IRUGO, mmc_omap_show_slot_name, NULL);
341 
342 static void
343 mmc_omap_start_command(struct mmc_omap_host *host, struct mmc_command *cmd)
344 {
345 	u32 cmdreg;
346 	u32 resptype;
347 	u32 cmdtype;
348 	u16 irq_mask;
349 
350 	host->cmd = cmd;
351 
352 	resptype = 0;
353 	cmdtype = 0;
354 
355 	/* Our hardware needs to know exact type */
356 	switch (mmc_resp_type(cmd)) {
357 	case MMC_RSP_NONE:
358 		break;
359 	case MMC_RSP_R1:
360 	case MMC_RSP_R1B:
361 		/* resp 1, 1b, 6, 7 */
362 		resptype = 1;
363 		break;
364 	case MMC_RSP_R2:
365 		resptype = 2;
366 		break;
367 	case MMC_RSP_R3:
368 		resptype = 3;
369 		break;
370 	default:
371 		dev_err(mmc_dev(host->mmc), "Invalid response type: %04x\n", mmc_resp_type(cmd));
372 		break;
373 	}
374 
375 	if (mmc_cmd_type(cmd) == MMC_CMD_ADTC) {
376 		cmdtype = OMAP_MMC_CMDTYPE_ADTC;
377 	} else if (mmc_cmd_type(cmd) == MMC_CMD_BC) {
378 		cmdtype = OMAP_MMC_CMDTYPE_BC;
379 	} else if (mmc_cmd_type(cmd) == MMC_CMD_BCR) {
380 		cmdtype = OMAP_MMC_CMDTYPE_BCR;
381 	} else {
382 		cmdtype = OMAP_MMC_CMDTYPE_AC;
383 	}
384 
385 	cmdreg = cmd->opcode | (resptype << 8) | (cmdtype << 12);
386 
387 	if (host->current_slot->bus_mode == MMC_BUSMODE_OPENDRAIN)
388 		cmdreg |= 1 << 6;
389 
390 	if (cmd->flags & MMC_RSP_BUSY)
391 		cmdreg |= 1 << 11;
392 
393 	if (host->data && !(host->data->flags & MMC_DATA_WRITE))
394 		cmdreg |= 1 << 15;
395 
396 	mod_timer(&host->cmd_abort_timer, jiffies + HZ/2);
397 
398 	OMAP_MMC_WRITE(host, CTO, 200);
399 	OMAP_MMC_WRITE(host, ARGL, cmd->arg & 0xffff);
400 	OMAP_MMC_WRITE(host, ARGH, cmd->arg >> 16);
401 	irq_mask = OMAP_MMC_STAT_A_EMPTY    | OMAP_MMC_STAT_A_FULL    |
402 		   OMAP_MMC_STAT_CMD_CRC    | OMAP_MMC_STAT_CMD_TOUT  |
403 		   OMAP_MMC_STAT_DATA_CRC   | OMAP_MMC_STAT_DATA_TOUT |
404 		   OMAP_MMC_STAT_END_OF_CMD | OMAP_MMC_STAT_CARD_ERR  |
405 		   OMAP_MMC_STAT_END_OF_DATA;
406 	if (cmd->opcode == MMC_ERASE)
407 		irq_mask &= ~OMAP_MMC_STAT_DATA_TOUT;
408 	OMAP_MMC_WRITE(host, IE, irq_mask);
409 	OMAP_MMC_WRITE(host, CMD, cmdreg);
410 }
411 
412 static void
413 mmc_omap_release_dma(struct mmc_omap_host *host, struct mmc_data *data,
414 		     int abort)
415 {
416 	enum dma_data_direction dma_data_dir;
417 	struct device *dev = mmc_dev(host->mmc);
418 	struct dma_chan *c;
419 
420 	if (data->flags & MMC_DATA_WRITE) {
421 		dma_data_dir = DMA_TO_DEVICE;
422 		c = host->dma_tx;
423 	} else {
424 		dma_data_dir = DMA_FROM_DEVICE;
425 		c = host->dma_rx;
426 	}
427 	if (c) {
428 		if (data->error) {
429 			dmaengine_terminate_all(c);
430 			/* Claim nothing transferred on error... */
431 			data->bytes_xfered = 0;
432 		}
433 		dev = c->device->dev;
434 	}
435 	dma_unmap_sg(dev, data->sg, host->sg_len, dma_data_dir);
436 }
437 
438 static void mmc_omap_send_stop_work(struct work_struct *work)
439 {
440 	struct mmc_omap_host *host = container_of(work, struct mmc_omap_host,
441 						  send_stop_work);
442 	struct mmc_omap_slot *slot = host->current_slot;
443 	struct mmc_data *data = host->stop_data;
444 	unsigned long tick_ns;
445 
446 	tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, slot->fclk_freq);
447 	ndelay(8*tick_ns);
448 
449 	mmc_omap_start_command(host, data->stop);
450 }
451 
452 static void
453 mmc_omap_xfer_done(struct mmc_omap_host *host, struct mmc_data *data)
454 {
455 	if (host->dma_in_use)
456 		mmc_omap_release_dma(host, data, data->error);
457 	else
458 		sg_miter_stop(&host->sg_miter);
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 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 	struct sg_mapping_iter *sgm = &host->sg_miter;
667 	int n, nwords;
668 	u16 *buffer;
669 
670 	if (!sg_miter_next(sgm)) {
671 		/* This should not happen */
672 		dev_err(mmc_dev(host->mmc), "ran out of scatterlist prematurely\n");
673 		return;
674 	}
675 	buffer = sgm->addr;
676 
677 	n = 64;
678 	if (n > sgm->length)
679 		n = sgm->length;
680 	if (n > host->total_bytes_left)
681 		n = host->total_bytes_left;
682 
683 	/* Round up to handle odd number of bytes to transfer */
684 	nwords = DIV_ROUND_UP(n, 2);
685 
686 	sgm->consumed = n;
687 	host->total_bytes_left -= n;
688 	host->data->bytes_xfered += n;
689 
690 	if (write) {
691 		__raw_writesw(host->virt_base + OMAP_MMC_REG(host, DATA),
692 			      buffer, nwords);
693 	} else {
694 		__raw_readsw(host->virt_base + OMAP_MMC_REG(host, DATA),
695 			     buffer, nwords);
696 	}
697 }
698 
699 #ifdef CONFIG_MMC_DEBUG
700 static void mmc_omap_report_irq(struct mmc_omap_host *host, u16 status)
701 {
702 	static const char *mmc_omap_status_bits[] = {
703 		"EOC", "CD", "CB", "BRS", "EOFB", "DTO", "DCRC", "CTO",
704 		"CCRC", "CRW", "AF", "AE", "OCRB", "CIRQ", "CERR"
705 	};
706 	int i;
707 	char res[64], *buf = res;
708 
709 	buf += sprintf(buf, "MMC IRQ 0x%x:", status);
710 
711 	for (i = 0; i < ARRAY_SIZE(mmc_omap_status_bits); i++)
712 		if (status & (1 << i))
713 			buf += sprintf(buf, " %s", mmc_omap_status_bits[i]);
714 	dev_vdbg(mmc_dev(host->mmc), "%s\n", res);
715 }
716 #else
717 static void mmc_omap_report_irq(struct mmc_omap_host *host, u16 status)
718 {
719 }
720 #endif
721 
722 
723 static irqreturn_t mmc_omap_irq(int irq, void *dev_id)
724 {
725 	struct mmc_omap_host * host = (struct mmc_omap_host *)dev_id;
726 	u16 status;
727 	int end_command;
728 	int end_transfer;
729 	int transfer_error, cmd_error;
730 
731 	if (host->cmd == NULL && host->data == NULL) {
732 		status = OMAP_MMC_READ(host, STAT);
733 		dev_info(mmc_dev(host->slots[0]->mmc),
734 			 "Spurious IRQ 0x%04x\n", status);
735 		if (status != 0) {
736 			OMAP_MMC_WRITE(host, STAT, status);
737 			OMAP_MMC_WRITE(host, IE, 0);
738 		}
739 		return IRQ_HANDLED;
740 	}
741 
742 	end_command = 0;
743 	end_transfer = 0;
744 	transfer_error = 0;
745 	cmd_error = 0;
746 
747 	while ((status = OMAP_MMC_READ(host, STAT)) != 0) {
748 		int cmd;
749 
750 		OMAP_MMC_WRITE(host, STAT, status);
751 		if (host->cmd != NULL)
752 			cmd = host->cmd->opcode;
753 		else
754 			cmd = -1;
755 		dev_dbg(mmc_dev(host->mmc), "MMC IRQ %04x (CMD %d): ",
756 			status, cmd);
757 		mmc_omap_report_irq(host, status);
758 
759 		if (host->total_bytes_left) {
760 			if ((status & OMAP_MMC_STAT_A_FULL) ||
761 			    (status & OMAP_MMC_STAT_END_OF_DATA))
762 				mmc_omap_xfer_data(host, 0);
763 			if (status & OMAP_MMC_STAT_A_EMPTY)
764 				mmc_omap_xfer_data(host, 1);
765 		}
766 
767 		if (status & OMAP_MMC_STAT_END_OF_DATA)
768 			end_transfer = 1;
769 
770 		if (status & OMAP_MMC_STAT_DATA_TOUT) {
771 			dev_dbg(mmc_dev(host->mmc), "data timeout (CMD%d)\n",
772 				cmd);
773 			if (host->data) {
774 				host->data->error = -ETIMEDOUT;
775 				transfer_error = 1;
776 			}
777 		}
778 
779 		if (status & OMAP_MMC_STAT_DATA_CRC) {
780 			if (host->data) {
781 				host->data->error = -EILSEQ;
782 				dev_dbg(mmc_dev(host->mmc),
783 					 "data CRC error, bytes left %d\n",
784 					host->total_bytes_left);
785 				transfer_error = 1;
786 			} else {
787 				dev_dbg(mmc_dev(host->mmc), "data CRC error\n");
788 			}
789 		}
790 
791 		if (status & OMAP_MMC_STAT_CMD_TOUT) {
792 			/* Timeouts are routine with some commands */
793 			if (host->cmd) {
794 				struct mmc_omap_slot *slot =
795 					host->current_slot;
796 				if (slot == NULL ||
797 				    !mmc_omap_cover_is_open(slot))
798 					dev_err(mmc_dev(host->mmc),
799 						"command timeout (CMD%d)\n",
800 						cmd);
801 				host->cmd->error = -ETIMEDOUT;
802 				end_command = 1;
803 				cmd_error = 1;
804 			}
805 		}
806 
807 		if (status & OMAP_MMC_STAT_CMD_CRC) {
808 			if (host->cmd) {
809 				dev_err(mmc_dev(host->mmc),
810 					"command CRC error (CMD%d, arg 0x%08x)\n",
811 					cmd, host->cmd->arg);
812 				host->cmd->error = -EILSEQ;
813 				end_command = 1;
814 				cmd_error = 1;
815 			} else
816 				dev_err(mmc_dev(host->mmc),
817 					"command CRC error without cmd?\n");
818 		}
819 
820 		if (status & OMAP_MMC_STAT_CARD_ERR) {
821 			dev_dbg(mmc_dev(host->mmc),
822 				"ignoring card status error (CMD%d)\n",
823 				cmd);
824 			end_command = 1;
825 		}
826 
827 		/*
828 		 * NOTE: On 1610 the END_OF_CMD may come too early when
829 		 * starting a write
830 		 */
831 		if ((status & OMAP_MMC_STAT_END_OF_CMD) &&
832 		    (!(status & OMAP_MMC_STAT_A_EMPTY))) {
833 			end_command = 1;
834 		}
835 	}
836 
837 	if (cmd_error && host->data) {
838 		del_timer(&host->cmd_abort_timer);
839 		host->abort = 1;
840 		OMAP_MMC_WRITE(host, IE, 0);
841 		disable_irq_nosync(host->irq);
842 		queue_work(host->mmc_omap_wq, &host->cmd_abort_work);
843 		return IRQ_HANDLED;
844 	}
845 
846 	if (end_command && host->cmd)
847 		mmc_omap_cmd_done(host, host->cmd);
848 	if (host->data != NULL) {
849 		if (transfer_error)
850 			mmc_omap_xfer_done(host, host->data);
851 		else if (end_transfer)
852 			mmc_omap_end_of_data(host, host->data);
853 	}
854 
855 	return IRQ_HANDLED;
856 }
857 
858 void omap_mmc_notify_cover_event(struct device *dev, int num, int is_closed)
859 {
860 	int cover_open;
861 	struct mmc_omap_host *host = dev_get_drvdata(dev);
862 	struct mmc_omap_slot *slot = host->slots[num];
863 
864 	BUG_ON(num >= host->nr_slots);
865 
866 	/* Other subsystems can call in here before we're initialised. */
867 	if (host->nr_slots == 0 || !host->slots[num])
868 		return;
869 
870 	cover_open = mmc_omap_cover_is_open(slot);
871 	if (cover_open != slot->cover_open) {
872 		slot->cover_open = cover_open;
873 		sysfs_notify(&slot->mmc->class_dev.kobj, NULL, "cover_switch");
874 	}
875 
876 	tasklet_hi_schedule(&slot->cover_tasklet);
877 }
878 
879 static void mmc_omap_cover_timer(struct timer_list *t)
880 {
881 	struct mmc_omap_slot *slot = from_timer(slot, t, cover_timer);
882 	tasklet_schedule(&slot->cover_tasklet);
883 }
884 
885 static void mmc_omap_cover_handler(struct tasklet_struct *t)
886 {
887 	struct mmc_omap_slot *slot = from_tasklet(slot, t, cover_tasklet);
888 	int cover_open = mmc_omap_cover_is_open(slot);
889 
890 	mmc_detect_change(slot->mmc, 0);
891 	if (!cover_open)
892 		return;
893 
894 	/*
895 	 * If no card is inserted, we postpone polling until
896 	 * the cover has been closed.
897 	 */
898 	if (slot->mmc->card == NULL)
899 		return;
900 
901 	mod_timer(&slot->cover_timer,
902 		  jiffies + msecs_to_jiffies(OMAP_MMC_COVER_POLL_DELAY));
903 }
904 
905 static void mmc_omap_dma_callback(void *priv)
906 {
907 	struct mmc_omap_host *host = priv;
908 	struct mmc_data *data = host->data;
909 
910 	/* If we got to the end of DMA, assume everything went well */
911 	data->bytes_xfered += data->blocks * data->blksz;
912 
913 	mmc_omap_dma_done(host, data);
914 }
915 
916 static inline void set_cmd_timeout(struct mmc_omap_host *host, struct mmc_request *req)
917 {
918 	u16 reg;
919 
920 	reg = OMAP_MMC_READ(host, SDIO);
921 	reg &= ~(1 << 5);
922 	OMAP_MMC_WRITE(host, SDIO, reg);
923 	/* Set maximum timeout */
924 	OMAP_MMC_WRITE(host, CTO, 0xfd);
925 }
926 
927 static inline void set_data_timeout(struct mmc_omap_host *host, struct mmc_request *req)
928 {
929 	unsigned int timeout, cycle_ns;
930 	u16 reg;
931 
932 	cycle_ns = 1000000000 / host->current_slot->fclk_freq;
933 	timeout = req->data->timeout_ns / cycle_ns;
934 	timeout += req->data->timeout_clks;
935 
936 	/* Check if we need to use timeout multiplier register */
937 	reg = OMAP_MMC_READ(host, SDIO);
938 	if (timeout > 0xffff) {
939 		reg |= (1 << 5);
940 		timeout /= 1024;
941 	} else
942 		reg &= ~(1 << 5);
943 	OMAP_MMC_WRITE(host, SDIO, reg);
944 	OMAP_MMC_WRITE(host, DTO, timeout);
945 }
946 
947 static void
948 mmc_omap_prepare_data(struct mmc_omap_host *host, struct mmc_request *req)
949 {
950 	unsigned int miter_flags = SG_MITER_ATOMIC; /* Used from IRQ */
951 	struct mmc_data *data = req->data;
952 	int i, use_dma = 1, block_size;
953 	struct scatterlist *sg;
954 	unsigned sg_len;
955 
956 	host->data = data;
957 	if (data == NULL) {
958 		OMAP_MMC_WRITE(host, BLEN, 0);
959 		OMAP_MMC_WRITE(host, NBLK, 0);
960 		OMAP_MMC_WRITE(host, BUF, 0);
961 		host->dma_in_use = 0;
962 		set_cmd_timeout(host, req);
963 		return;
964 	}
965 
966 	block_size = data->blksz;
967 
968 	OMAP_MMC_WRITE(host, NBLK, data->blocks - 1);
969 	OMAP_MMC_WRITE(host, BLEN, block_size - 1);
970 	set_data_timeout(host, req);
971 
972 	/* cope with calling layer confusion; it issues "single
973 	 * block" writes using multi-block scatterlists.
974 	 */
975 	sg_len = (data->blocks == 1) ? 1 : data->sg_len;
976 
977 	/* Only do DMA for entire blocks */
978 	for_each_sg(data->sg, sg, sg_len, i) {
979 		if ((sg->length % block_size) != 0) {
980 			use_dma = 0;
981 			break;
982 		}
983 	}
984 
985 	if (use_dma) {
986 		enum dma_data_direction dma_data_dir;
987 		struct dma_async_tx_descriptor *tx;
988 		struct dma_chan *c;
989 		u32 burst, *bp;
990 		u16 buf;
991 
992 		/*
993 		 * FIFO is 16x2 bytes on 15xx, and 32x2 bytes on 16xx
994 		 * and 24xx. Use 16 or 32 word frames when the
995 		 * blocksize is at least that large. Blocksize is
996 		 * usually 512 bytes; but not for some SD reads.
997 		 */
998 		burst = mmc_omap15xx() ? 32 : 64;
999 		if (burst > data->blksz)
1000 			burst = data->blksz;
1001 
1002 		burst >>= 1;
1003 
1004 		if (data->flags & MMC_DATA_WRITE) {
1005 			c = host->dma_tx;
1006 			bp = &host->dma_tx_burst;
1007 			buf = 0x0f80 | (burst - 1) << 0;
1008 			dma_data_dir = DMA_TO_DEVICE;
1009 		} else {
1010 			c = host->dma_rx;
1011 			bp = &host->dma_rx_burst;
1012 			buf = 0x800f | (burst - 1) << 8;
1013 			dma_data_dir = DMA_FROM_DEVICE;
1014 		}
1015 
1016 		if (!c)
1017 			goto use_pio;
1018 
1019 		/* Only reconfigure if we have a different burst size */
1020 		if (*bp != burst) {
1021 			struct dma_slave_config cfg = {
1022 				.src_addr = host->phys_base +
1023 					    OMAP_MMC_REG(host, DATA),
1024 				.dst_addr = host->phys_base +
1025 					    OMAP_MMC_REG(host, DATA),
1026 				.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES,
1027 				.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES,
1028 				.src_maxburst = burst,
1029 				.dst_maxburst = burst,
1030 			};
1031 
1032 			if (dmaengine_slave_config(c, &cfg))
1033 				goto use_pio;
1034 
1035 			*bp = burst;
1036 		}
1037 
1038 		host->sg_len = dma_map_sg(c->device->dev, data->sg, sg_len,
1039 					  dma_data_dir);
1040 		if (host->sg_len == 0)
1041 			goto use_pio;
1042 
1043 		tx = dmaengine_prep_slave_sg(c, data->sg, host->sg_len,
1044 			data->flags & MMC_DATA_WRITE ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM,
1045 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1046 		if (!tx)
1047 			goto use_pio;
1048 
1049 		OMAP_MMC_WRITE(host, BUF, buf);
1050 
1051 		tx->callback = mmc_omap_dma_callback;
1052 		tx->callback_param = host;
1053 		dmaengine_submit(tx);
1054 		host->brs_received = 0;
1055 		host->dma_done = 0;
1056 		host->dma_in_use = 1;
1057 		return;
1058 	}
1059  use_pio:
1060 
1061 	/* Revert to PIO? */
1062 	OMAP_MMC_WRITE(host, BUF, 0x1f1f);
1063 	host->total_bytes_left = data->blocks * block_size;
1064 	host->sg_len = sg_len;
1065 	if (data->flags & MMC_DATA_READ)
1066 		miter_flags |= SG_MITER_TO_SG;
1067 	else
1068 		miter_flags |= SG_MITER_FROM_SG;
1069 	sg_miter_start(&host->sg_miter, data->sg, data->sg_len, miter_flags);
1070 	host->dma_in_use = 0;
1071 }
1072 
1073 static void mmc_omap_start_request(struct mmc_omap_host *host,
1074 				   struct mmc_request *req)
1075 {
1076 	BUG_ON(host->mrq != NULL);
1077 
1078 	host->mrq = req;
1079 
1080 	/* only touch fifo AFTER the controller readies it */
1081 	mmc_omap_prepare_data(host, req);
1082 	mmc_omap_start_command(host, req->cmd);
1083 	if (host->dma_in_use) {
1084 		struct dma_chan *c = host->data->flags & MMC_DATA_WRITE ?
1085 				host->dma_tx : host->dma_rx;
1086 
1087 		dma_async_issue_pending(c);
1088 	}
1089 }
1090 
1091 static void mmc_omap_request(struct mmc_host *mmc, struct mmc_request *req)
1092 {
1093 	struct mmc_omap_slot *slot = mmc_priv(mmc);
1094 	struct mmc_omap_host *host = slot->host;
1095 	unsigned long flags;
1096 
1097 	spin_lock_irqsave(&host->slot_lock, flags);
1098 	if (host->mmc != NULL) {
1099 		BUG_ON(slot->mrq != NULL);
1100 		slot->mrq = req;
1101 		spin_unlock_irqrestore(&host->slot_lock, flags);
1102 		return;
1103 	} else
1104 		host->mmc = mmc;
1105 	spin_unlock_irqrestore(&host->slot_lock, flags);
1106 	mmc_omap_select_slot(slot, 1);
1107 	mmc_omap_start_request(host, req);
1108 }
1109 
1110 static void mmc_omap_set_power(struct mmc_omap_slot *slot, int power_on,
1111 				int vdd)
1112 {
1113 	struct mmc_omap_host *host;
1114 
1115 	host = slot->host;
1116 
1117 	if (slot->vsd)
1118 		gpiod_set_value(slot->vsd, power_on);
1119 	if (slot->vio)
1120 		gpiod_set_value(slot->vio, power_on);
1121 
1122 	if (slot->pdata->set_power != NULL)
1123 		slot->pdata->set_power(mmc_dev(slot->mmc), slot->id, power_on,
1124 					vdd);
1125 	if (mmc_omap2()) {
1126 		u16 w;
1127 
1128 		if (power_on) {
1129 			w = OMAP_MMC_READ(host, CON);
1130 			OMAP_MMC_WRITE(host, CON, w | (1 << 11));
1131 		} else {
1132 			w = OMAP_MMC_READ(host, CON);
1133 			OMAP_MMC_WRITE(host, CON, w & ~(1 << 11));
1134 		}
1135 	}
1136 }
1137 
1138 static int mmc_omap_calc_divisor(struct mmc_host *mmc, struct mmc_ios *ios)
1139 {
1140 	struct mmc_omap_slot *slot = mmc_priv(mmc);
1141 	struct mmc_omap_host *host = slot->host;
1142 	int func_clk_rate = clk_get_rate(host->fclk);
1143 	int dsor;
1144 
1145 	if (ios->clock == 0)
1146 		return 0;
1147 
1148 	dsor = func_clk_rate / ios->clock;
1149 	if (dsor < 1)
1150 		dsor = 1;
1151 
1152 	if (func_clk_rate / dsor > ios->clock)
1153 		dsor++;
1154 
1155 	if (dsor > 250)
1156 		dsor = 250;
1157 
1158 	slot->fclk_freq = func_clk_rate / dsor;
1159 
1160 	if (ios->bus_width == MMC_BUS_WIDTH_4)
1161 		dsor |= 1 << 15;
1162 
1163 	return dsor;
1164 }
1165 
1166 static void mmc_omap_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
1167 {
1168 	struct mmc_omap_slot *slot = mmc_priv(mmc);
1169 	struct mmc_omap_host *host = slot->host;
1170 	int i, dsor;
1171 	int clk_enabled, init_stream;
1172 
1173 	mmc_omap_select_slot(slot, 0);
1174 
1175 	dsor = mmc_omap_calc_divisor(mmc, ios);
1176 
1177 	if (ios->vdd != slot->vdd)
1178 		slot->vdd = ios->vdd;
1179 
1180 	clk_enabled = 0;
1181 	init_stream = 0;
1182 	switch (ios->power_mode) {
1183 	case MMC_POWER_OFF:
1184 		mmc_omap_set_power(slot, 0, ios->vdd);
1185 		break;
1186 	case MMC_POWER_UP:
1187 		/* Cannot touch dsor yet, just power up MMC */
1188 		mmc_omap_set_power(slot, 1, ios->vdd);
1189 		slot->power_mode = ios->power_mode;
1190 		goto exit;
1191 	case MMC_POWER_ON:
1192 		mmc_omap_fclk_enable(host, 1);
1193 		clk_enabled = 1;
1194 		dsor |= 1 << 11;
1195 		if (slot->power_mode != MMC_POWER_ON)
1196 			init_stream = 1;
1197 		break;
1198 	}
1199 	slot->power_mode = ios->power_mode;
1200 
1201 	if (slot->bus_mode != ios->bus_mode) {
1202 		if (slot->pdata->set_bus_mode != NULL)
1203 			slot->pdata->set_bus_mode(mmc_dev(mmc), slot->id,
1204 						  ios->bus_mode);
1205 		slot->bus_mode = ios->bus_mode;
1206 	}
1207 
1208 	/* On insanely high arm_per frequencies something sometimes
1209 	 * goes somehow out of sync, and the POW bit is not being set,
1210 	 * which results in the while loop below getting stuck.
1211 	 * Writing to the CON register twice seems to do the trick. */
1212 	for (i = 0; i < 2; i++)
1213 		OMAP_MMC_WRITE(host, CON, dsor);
1214 	slot->saved_con = dsor;
1215 	if (init_stream) {
1216 		/* worst case at 400kHz, 80 cycles makes 200 microsecs */
1217 		int usecs = 250;
1218 
1219 		/* Send clock cycles, poll completion */
1220 		OMAP_MMC_WRITE(host, IE, 0);
1221 		OMAP_MMC_WRITE(host, STAT, 0xffff);
1222 		OMAP_MMC_WRITE(host, CMD, 1 << 7);
1223 		while (usecs > 0 && (OMAP_MMC_READ(host, STAT) & 1) == 0) {
1224 			udelay(1);
1225 			usecs--;
1226 		}
1227 		OMAP_MMC_WRITE(host, STAT, 1);
1228 	}
1229 
1230 exit:
1231 	mmc_omap_release_slot(slot, clk_enabled);
1232 }
1233 
1234 static const struct mmc_host_ops mmc_omap_ops = {
1235 	.request	= mmc_omap_request,
1236 	.set_ios	= mmc_omap_set_ios,
1237 };
1238 
1239 static int mmc_omap_new_slot(struct mmc_omap_host *host, int id)
1240 {
1241 	struct mmc_omap_slot *slot = NULL;
1242 	struct mmc_host *mmc;
1243 	int r;
1244 
1245 	mmc = mmc_alloc_host(sizeof(struct mmc_omap_slot), host->dev);
1246 	if (mmc == NULL)
1247 		return -ENOMEM;
1248 
1249 	slot = mmc_priv(mmc);
1250 	slot->host = host;
1251 	slot->mmc = mmc;
1252 	slot->id = id;
1253 	slot->power_mode = MMC_POWER_UNDEFINED;
1254 	slot->pdata = &host->pdata->slots[id];
1255 
1256 	/* Check for some optional GPIO controls */
1257 	slot->vsd = gpiod_get_index_optional(host->dev, "vsd",
1258 					     id, GPIOD_OUT_LOW);
1259 	if (IS_ERR(slot->vsd))
1260 		return dev_err_probe(host->dev, PTR_ERR(slot->vsd),
1261 				     "error looking up VSD GPIO\n");
1262 	slot->vio = gpiod_get_index_optional(host->dev, "vio",
1263 					     id, GPIOD_OUT_LOW);
1264 	if (IS_ERR(slot->vio))
1265 		return dev_err_probe(host->dev, PTR_ERR(slot->vio),
1266 				     "error looking up VIO GPIO\n");
1267 	slot->cover = gpiod_get_index_optional(host->dev, "cover",
1268 						id, GPIOD_IN);
1269 	if (IS_ERR(slot->cover))
1270 		return dev_err_probe(host->dev, PTR_ERR(slot->cover),
1271 				     "error looking up cover switch GPIO\n");
1272 
1273 	host->slots[id] = slot;
1274 
1275 	mmc->caps = 0;
1276 	if (host->pdata->slots[id].wires >= 4)
1277 		mmc->caps |= MMC_CAP_4_BIT_DATA;
1278 
1279 	mmc->ops = &mmc_omap_ops;
1280 	mmc->f_min = 400000;
1281 
1282 	if (mmc_omap2())
1283 		mmc->f_max = 48000000;
1284 	else
1285 		mmc->f_max = 24000000;
1286 	if (host->pdata->max_freq)
1287 		mmc->f_max = min(host->pdata->max_freq, mmc->f_max);
1288 	mmc->ocr_avail = slot->pdata->ocr_mask;
1289 
1290 	/* Use scatterlist DMA to reduce per-transfer costs.
1291 	 * NOTE max_seg_size assumption that small blocks aren't
1292 	 * normally used (except e.g. for reading SD registers).
1293 	 */
1294 	mmc->max_segs = 32;
1295 	mmc->max_blk_size = 2048;	/* BLEN is 11 bits (+1) */
1296 	mmc->max_blk_count = 2048;	/* NBLK is 11 bits (+1) */
1297 	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
1298 	mmc->max_seg_size = mmc->max_req_size;
1299 
1300 	if (slot->pdata->get_cover_state != NULL) {
1301 		timer_setup(&slot->cover_timer, mmc_omap_cover_timer, 0);
1302 		tasklet_setup(&slot->cover_tasklet, mmc_omap_cover_handler);
1303 	}
1304 
1305 	r = mmc_add_host(mmc);
1306 	if (r < 0)
1307 		goto err_remove_host;
1308 
1309 	if (slot->pdata->name != NULL) {
1310 		r = device_create_file(&mmc->class_dev,
1311 					&dev_attr_slot_name);
1312 		if (r < 0)
1313 			goto err_remove_host;
1314 	}
1315 
1316 	if (slot->pdata->get_cover_state != NULL) {
1317 		r = device_create_file(&mmc->class_dev,
1318 					&dev_attr_cover_switch);
1319 		if (r < 0)
1320 			goto err_remove_slot_name;
1321 		tasklet_schedule(&slot->cover_tasklet);
1322 	}
1323 
1324 	return 0;
1325 
1326 err_remove_slot_name:
1327 	if (slot->pdata->name != NULL)
1328 		device_remove_file(&mmc->class_dev, &dev_attr_slot_name);
1329 err_remove_host:
1330 	mmc_remove_host(mmc);
1331 	mmc_free_host(mmc);
1332 	return r;
1333 }
1334 
1335 static void mmc_omap_remove_slot(struct mmc_omap_slot *slot)
1336 {
1337 	struct mmc_host *mmc = slot->mmc;
1338 
1339 	if (slot->pdata->name != NULL)
1340 		device_remove_file(&mmc->class_dev, &dev_attr_slot_name);
1341 	if (slot->pdata->get_cover_state != NULL)
1342 		device_remove_file(&mmc->class_dev, &dev_attr_cover_switch);
1343 
1344 	tasklet_kill(&slot->cover_tasklet);
1345 	del_timer_sync(&slot->cover_timer);
1346 	flush_workqueue(slot->host->mmc_omap_wq);
1347 
1348 	mmc_remove_host(mmc);
1349 	mmc_free_host(mmc);
1350 }
1351 
1352 static int mmc_omap_probe(struct platform_device *pdev)
1353 {
1354 	struct omap_mmc_platform_data *pdata = pdev->dev.platform_data;
1355 	struct mmc_omap_host *host = NULL;
1356 	struct resource *res;
1357 	int i, ret = 0;
1358 	int irq;
1359 
1360 	if (pdata == NULL) {
1361 		dev_err(&pdev->dev, "platform data missing\n");
1362 		return -ENXIO;
1363 	}
1364 	if (pdata->nr_slots == 0) {
1365 		dev_err(&pdev->dev, "no slots\n");
1366 		return -EPROBE_DEFER;
1367 	}
1368 
1369 	host = devm_kzalloc(&pdev->dev, sizeof(struct mmc_omap_host),
1370 			    GFP_KERNEL);
1371 	if (host == NULL)
1372 		return -ENOMEM;
1373 
1374 	irq = platform_get_irq(pdev, 0);
1375 	if (irq < 0)
1376 		return irq;
1377 
1378 	host->virt_base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1379 	if (IS_ERR(host->virt_base))
1380 		return PTR_ERR(host->virt_base);
1381 
1382 	host->slot_switch = gpiod_get_optional(host->dev, "switch",
1383 					       GPIOD_OUT_LOW);
1384 	if (IS_ERR(host->slot_switch))
1385 		return dev_err_probe(host->dev, PTR_ERR(host->slot_switch),
1386 				     "error looking up slot switch GPIO\n");
1387 
1388 
1389 	INIT_WORK(&host->slot_release_work, mmc_omap_slot_release_work);
1390 	INIT_WORK(&host->send_stop_work, mmc_omap_send_stop_work);
1391 
1392 	INIT_WORK(&host->cmd_abort_work, mmc_omap_abort_command);
1393 	timer_setup(&host->cmd_abort_timer, mmc_omap_cmd_timer, 0);
1394 
1395 	spin_lock_init(&host->clk_lock);
1396 	timer_setup(&host->clk_timer, mmc_omap_clk_timer, 0);
1397 
1398 	spin_lock_init(&host->dma_lock);
1399 	spin_lock_init(&host->slot_lock);
1400 	init_waitqueue_head(&host->slot_wq);
1401 
1402 	host->pdata = pdata;
1403 	host->features = host->pdata->slots[0].features;
1404 	host->dev = &pdev->dev;
1405 	platform_set_drvdata(pdev, host);
1406 
1407 	host->id = pdev->id;
1408 	host->irq = irq;
1409 	host->phys_base = res->start;
1410 	host->iclk = clk_get(&pdev->dev, "ick");
1411 	if (IS_ERR(host->iclk))
1412 		return PTR_ERR(host->iclk);
1413 	clk_prepare_enable(host->iclk);
1414 
1415 	host->fclk = clk_get(&pdev->dev, "fck");
1416 	if (IS_ERR(host->fclk)) {
1417 		ret = PTR_ERR(host->fclk);
1418 		goto err_free_iclk;
1419 	}
1420 
1421 	ret = clk_prepare(host->fclk);
1422 	if (ret)
1423 		goto err_put_fclk;
1424 
1425 	host->dma_tx_burst = -1;
1426 	host->dma_rx_burst = -1;
1427 
1428 	host->dma_tx = dma_request_chan(&pdev->dev, "tx");
1429 	if (IS_ERR(host->dma_tx)) {
1430 		ret = PTR_ERR(host->dma_tx);
1431 		if (ret == -EPROBE_DEFER)
1432 			goto err_free_fclk;
1433 
1434 		host->dma_tx = NULL;
1435 		dev_warn(host->dev, "TX DMA channel request failed\n");
1436 	}
1437 
1438 	host->dma_rx = dma_request_chan(&pdev->dev, "rx");
1439 	if (IS_ERR(host->dma_rx)) {
1440 		ret = PTR_ERR(host->dma_rx);
1441 		if (ret == -EPROBE_DEFER) {
1442 			if (host->dma_tx)
1443 				dma_release_channel(host->dma_tx);
1444 			goto err_free_fclk;
1445 		}
1446 
1447 		host->dma_rx = NULL;
1448 		dev_warn(host->dev, "RX DMA channel request failed\n");
1449 	}
1450 
1451 	ret = request_irq(host->irq, mmc_omap_irq, 0, DRIVER_NAME, host);
1452 	if (ret)
1453 		goto err_free_dma;
1454 
1455 	if (pdata->init != NULL) {
1456 		ret = pdata->init(&pdev->dev);
1457 		if (ret < 0)
1458 			goto err_free_irq;
1459 	}
1460 
1461 	host->nr_slots = pdata->nr_slots;
1462 	host->reg_shift = (mmc_omap7xx() ? 1 : 2);
1463 
1464 	host->mmc_omap_wq = alloc_workqueue("mmc_omap", 0, 0);
1465 	if (!host->mmc_omap_wq) {
1466 		ret = -ENOMEM;
1467 		goto err_plat_cleanup;
1468 	}
1469 
1470 	for (i = 0; i < pdata->nr_slots; i++) {
1471 		ret = mmc_omap_new_slot(host, i);
1472 		if (ret < 0) {
1473 			while (--i >= 0)
1474 				mmc_omap_remove_slot(host->slots[i]);
1475 
1476 			goto err_destroy_wq;
1477 		}
1478 	}
1479 
1480 	return 0;
1481 
1482 err_destroy_wq:
1483 	destroy_workqueue(host->mmc_omap_wq);
1484 err_plat_cleanup:
1485 	if (pdata->cleanup)
1486 		pdata->cleanup(&pdev->dev);
1487 err_free_irq:
1488 	free_irq(host->irq, host);
1489 err_free_dma:
1490 	if (host->dma_tx)
1491 		dma_release_channel(host->dma_tx);
1492 	if (host->dma_rx)
1493 		dma_release_channel(host->dma_rx);
1494 err_free_fclk:
1495 	clk_unprepare(host->fclk);
1496 err_put_fclk:
1497 	clk_put(host->fclk);
1498 err_free_iclk:
1499 	clk_disable_unprepare(host->iclk);
1500 	clk_put(host->iclk);
1501 	return ret;
1502 }
1503 
1504 static void mmc_omap_remove(struct platform_device *pdev)
1505 {
1506 	struct mmc_omap_host *host = platform_get_drvdata(pdev);
1507 	int i;
1508 
1509 	BUG_ON(host == NULL);
1510 
1511 	for (i = 0; i < host->nr_slots; i++)
1512 		mmc_omap_remove_slot(host->slots[i]);
1513 
1514 	if (host->pdata->cleanup)
1515 		host->pdata->cleanup(&pdev->dev);
1516 
1517 	mmc_omap_fclk_enable(host, 0);
1518 	free_irq(host->irq, host);
1519 	clk_unprepare(host->fclk);
1520 	clk_put(host->fclk);
1521 	clk_disable_unprepare(host->iclk);
1522 	clk_put(host->iclk);
1523 
1524 	if (host->dma_tx)
1525 		dma_release_channel(host->dma_tx);
1526 	if (host->dma_rx)
1527 		dma_release_channel(host->dma_rx);
1528 
1529 	destroy_workqueue(host->mmc_omap_wq);
1530 }
1531 
1532 #if IS_BUILTIN(CONFIG_OF)
1533 static const struct of_device_id mmc_omap_match[] = {
1534 	{ .compatible = "ti,omap2420-mmc", },
1535 	{ },
1536 };
1537 MODULE_DEVICE_TABLE(of, mmc_omap_match);
1538 #endif
1539 
1540 static struct platform_driver mmc_omap_driver = {
1541 	.probe		= mmc_omap_probe,
1542 	.remove_new	= mmc_omap_remove,
1543 	.driver		= {
1544 		.name	= DRIVER_NAME,
1545 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1546 		.of_match_table = of_match_ptr(mmc_omap_match),
1547 	},
1548 };
1549 
1550 module_platform_driver(mmc_omap_driver);
1551 MODULE_DESCRIPTION("OMAP Multimedia Card driver");
1552 MODULE_LICENSE("GPL");
1553 MODULE_ALIAS("platform:" DRIVER_NAME);
1554 MODULE_AUTHOR("Juha Yrjölä");
1555