xref: /openbmc/linux/drivers/mmc/host/atmel-mci.c (revision 76d55564)
1 /*
2  * Atmel MultiMedia Card Interface driver
3  *
4  * Copyright (C) 2004-2008 Atmel Corporation
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 #include <linux/blkdev.h>
11 #include <linux/clk.h>
12 #include <linux/debugfs.h>
13 #include <linux/device.h>
14 #include <linux/dmaengine.h>
15 #include <linux/dma-mapping.h>
16 #include <linux/err.h>
17 #include <linux/gpio.h>
18 #include <linux/init.h>
19 #include <linux/interrupt.h>
20 #include <linux/io.h>
21 #include <linux/ioport.h>
22 #include <linux/module.h>
23 #include <linux/of.h>
24 #include <linux/of_device.h>
25 #include <linux/of_gpio.h>
26 #include <linux/platform_device.h>
27 #include <linux/scatterlist.h>
28 #include <linux/seq_file.h>
29 #include <linux/slab.h>
30 #include <linux/stat.h>
31 #include <linux/types.h>
32 #include <linux/platform_data/atmel.h>
33 #include <linux/platform_data/mmc-atmel-mci.h>
34 
35 #include <linux/mmc/host.h>
36 #include <linux/mmc/sdio.h>
37 
38 #include <linux/atmel-mci.h>
39 #include <linux/atmel_pdc.h>
40 
41 #include <asm/cacheflush.h>
42 #include <asm/io.h>
43 #include <asm/unaligned.h>
44 
45 #include "atmel-mci-regs.h"
46 
47 #define ATMCI_DATA_ERROR_FLAGS	(ATMCI_DCRCE | ATMCI_DTOE | ATMCI_OVRE | ATMCI_UNRE)
48 #define ATMCI_DMA_THRESHOLD	16
49 
50 enum {
51 	EVENT_CMD_RDY = 0,
52 	EVENT_XFER_COMPLETE,
53 	EVENT_NOTBUSY,
54 	EVENT_DATA_ERROR,
55 };
56 
57 enum atmel_mci_state {
58 	STATE_IDLE = 0,
59 	STATE_SENDING_CMD,
60 	STATE_DATA_XFER,
61 	STATE_WAITING_NOTBUSY,
62 	STATE_SENDING_STOP,
63 	STATE_END_REQUEST,
64 };
65 
66 enum atmci_xfer_dir {
67 	XFER_RECEIVE = 0,
68 	XFER_TRANSMIT,
69 };
70 
71 enum atmci_pdc_buf {
72 	PDC_FIRST_BUF = 0,
73 	PDC_SECOND_BUF,
74 };
75 
76 struct atmel_mci_caps {
77 	bool    has_dma_conf_reg;
78 	bool    has_pdc;
79 	bool    has_cfg_reg;
80 	bool    has_cstor_reg;
81 	bool    has_highspeed;
82 	bool    has_rwproof;
83 	bool	has_odd_clk_div;
84 	bool	has_bad_data_ordering;
85 	bool	need_reset_after_xfer;
86 	bool	need_blksz_mul_4;
87 	bool	need_notbusy_for_read_ops;
88 };
89 
90 struct atmel_mci_dma {
91 	struct dma_chan			*chan;
92 	struct dma_async_tx_descriptor	*data_desc;
93 };
94 
95 /**
96  * struct atmel_mci - MMC controller state shared between all slots
97  * @lock: Spinlock protecting the queue and associated data.
98  * @regs: Pointer to MMIO registers.
99  * @sg: Scatterlist entry currently being processed by PIO or PDC code.
100  * @pio_offset: Offset into the current scatterlist entry.
101  * @buffer: Buffer used if we don't have the r/w proof capability. We
102  *      don't have the time to switch pdc buffers so we have to use only
103  *      one buffer for the full transaction.
104  * @buf_size: size of the buffer.
105  * @phys_buf_addr: buffer address needed for pdc.
106  * @cur_slot: The slot which is currently using the controller.
107  * @mrq: The request currently being processed on @cur_slot,
108  *	or NULL if the controller is idle.
109  * @cmd: The command currently being sent to the card, or NULL.
110  * @data: The data currently being transferred, or NULL if no data
111  *	transfer is in progress.
112  * @data_size: just data->blocks * data->blksz.
113  * @dma: DMA client state.
114  * @data_chan: DMA channel being used for the current data transfer.
115  * @cmd_status: Snapshot of SR taken upon completion of the current
116  *	command. Only valid when EVENT_CMD_COMPLETE is pending.
117  * @data_status: Snapshot of SR taken upon completion of the current
118  *	data transfer. Only valid when EVENT_DATA_COMPLETE or
119  *	EVENT_DATA_ERROR is pending.
120  * @stop_cmdr: Value to be loaded into CMDR when the stop command is
121  *	to be sent.
122  * @tasklet: Tasklet running the request state machine.
123  * @pending_events: Bitmask of events flagged by the interrupt handler
124  *	to be processed by the tasklet.
125  * @completed_events: Bitmask of events which the state machine has
126  *	processed.
127  * @state: Tasklet state.
128  * @queue: List of slots waiting for access to the controller.
129  * @need_clock_update: Update the clock rate before the next request.
130  * @need_reset: Reset controller before next request.
131  * @timer: Timer to balance the data timeout error flag which cannot rise.
132  * @mode_reg: Value of the MR register.
133  * @cfg_reg: Value of the CFG register.
134  * @bus_hz: The rate of @mck in Hz. This forms the basis for MMC bus
135  *	rate and timeout calculations.
136  * @mapbase: Physical address of the MMIO registers.
137  * @mck: The peripheral bus clock hooked up to the MMC controller.
138  * @pdev: Platform device associated with the MMC controller.
139  * @slot: Slots sharing this MMC controller.
140  * @caps: MCI capabilities depending on MCI version.
141  * @prepare_data: function to setup MCI before data transfer which
142  * depends on MCI capabilities.
143  * @submit_data: function to start data transfer which depends on MCI
144  * capabilities.
145  * @stop_transfer: function to stop data transfer which depends on MCI
146  * capabilities.
147  *
148  * Locking
149  * =======
150  *
151  * @lock is a softirq-safe spinlock protecting @queue as well as
152  * @cur_slot, @mrq and @state. These must always be updated
153  * at the same time while holding @lock.
154  *
155  * @lock also protects mode_reg and need_clock_update since these are
156  * used to synchronize mode register updates with the queue
157  * processing.
158  *
159  * The @mrq field of struct atmel_mci_slot is also protected by @lock,
160  * and must always be written at the same time as the slot is added to
161  * @queue.
162  *
163  * @pending_events and @completed_events are accessed using atomic bit
164  * operations, so they don't need any locking.
165  *
166  * None of the fields touched by the interrupt handler need any
167  * locking. However, ordering is important: Before EVENT_DATA_ERROR or
168  * EVENT_DATA_COMPLETE is set in @pending_events, all data-related
169  * interrupts must be disabled and @data_status updated with a
170  * snapshot of SR. Similarly, before EVENT_CMD_COMPLETE is set, the
171  * CMDRDY interrupt must be disabled and @cmd_status updated with a
172  * snapshot of SR, and before EVENT_XFER_COMPLETE can be set, the
173  * bytes_xfered field of @data must be written. This is ensured by
174  * using barriers.
175  */
176 struct atmel_mci {
177 	spinlock_t		lock;
178 	void __iomem		*regs;
179 
180 	struct scatterlist	*sg;
181 	unsigned int		sg_len;
182 	unsigned int		pio_offset;
183 	unsigned int		*buffer;
184 	unsigned int		buf_size;
185 	dma_addr_t		buf_phys_addr;
186 
187 	struct atmel_mci_slot	*cur_slot;
188 	struct mmc_request	*mrq;
189 	struct mmc_command	*cmd;
190 	struct mmc_data		*data;
191 	unsigned int		data_size;
192 
193 	struct atmel_mci_dma	dma;
194 	struct dma_chan		*data_chan;
195 	struct dma_slave_config	dma_conf;
196 
197 	u32			cmd_status;
198 	u32			data_status;
199 	u32			stop_cmdr;
200 
201 	struct tasklet_struct	tasklet;
202 	unsigned long		pending_events;
203 	unsigned long		completed_events;
204 	enum atmel_mci_state	state;
205 	struct list_head	queue;
206 
207 	bool			need_clock_update;
208 	bool			need_reset;
209 	struct timer_list	timer;
210 	u32			mode_reg;
211 	u32			cfg_reg;
212 	unsigned long		bus_hz;
213 	unsigned long		mapbase;
214 	struct clk		*mck;
215 	struct platform_device	*pdev;
216 
217 	struct atmel_mci_slot	*slot[ATMCI_MAX_NR_SLOTS];
218 
219 	struct atmel_mci_caps   caps;
220 
221 	u32 (*prepare_data)(struct atmel_mci *host, struct mmc_data *data);
222 	void (*submit_data)(struct atmel_mci *host, struct mmc_data *data);
223 	void (*stop_transfer)(struct atmel_mci *host);
224 };
225 
226 /**
227  * struct atmel_mci_slot - MMC slot state
228  * @mmc: The mmc_host representing this slot.
229  * @host: The MMC controller this slot is using.
230  * @sdc_reg: Value of SDCR to be written before using this slot.
231  * @sdio_irq: SDIO irq mask for this slot.
232  * @mrq: mmc_request currently being processed or waiting to be
233  *	processed, or NULL when the slot is idle.
234  * @queue_node: List node for placing this node in the @queue list of
235  *	&struct atmel_mci.
236  * @clock: Clock rate configured by set_ios(). Protected by host->lock.
237  * @flags: Random state bits associated with the slot.
238  * @detect_pin: GPIO pin used for card detection, or negative if not
239  *	available.
240  * @wp_pin: GPIO pin used for card write protect sending, or negative
241  *	if not available.
242  * @detect_is_active_high: The state of the detect pin when it is active.
243  * @detect_timer: Timer used for debouncing @detect_pin interrupts.
244  */
245 struct atmel_mci_slot {
246 	struct mmc_host		*mmc;
247 	struct atmel_mci	*host;
248 
249 	u32			sdc_reg;
250 	u32			sdio_irq;
251 
252 	struct mmc_request	*mrq;
253 	struct list_head	queue_node;
254 
255 	unsigned int		clock;
256 	unsigned long		flags;
257 #define ATMCI_CARD_PRESENT	0
258 #define ATMCI_CARD_NEED_INIT	1
259 #define ATMCI_SHUTDOWN		2
260 
261 	int			detect_pin;
262 	int			wp_pin;
263 	bool			detect_is_active_high;
264 
265 	struct timer_list	detect_timer;
266 };
267 
268 #define atmci_test_and_clear_pending(host, event)		\
269 	test_and_clear_bit(event, &host->pending_events)
270 #define atmci_set_completed(host, event)			\
271 	set_bit(event, &host->completed_events)
272 #define atmci_set_pending(host, event)				\
273 	set_bit(event, &host->pending_events)
274 
275 /*
276  * The debugfs stuff below is mostly optimized away when
277  * CONFIG_DEBUG_FS is not set.
278  */
279 static int atmci_req_show(struct seq_file *s, void *v)
280 {
281 	struct atmel_mci_slot	*slot = s->private;
282 	struct mmc_request	*mrq;
283 	struct mmc_command	*cmd;
284 	struct mmc_command	*stop;
285 	struct mmc_data		*data;
286 
287 	/* Make sure we get a consistent snapshot */
288 	spin_lock_bh(&slot->host->lock);
289 	mrq = slot->mrq;
290 
291 	if (mrq) {
292 		cmd = mrq->cmd;
293 		data = mrq->data;
294 		stop = mrq->stop;
295 
296 		if (cmd)
297 			seq_printf(s,
298 				"CMD%u(0x%x) flg %x rsp %x %x %x %x err %d\n",
299 				cmd->opcode, cmd->arg, cmd->flags,
300 				cmd->resp[0], cmd->resp[1], cmd->resp[2],
301 				cmd->resp[3], cmd->error);
302 		if (data)
303 			seq_printf(s, "DATA %u / %u * %u flg %x err %d\n",
304 				data->bytes_xfered, data->blocks,
305 				data->blksz, data->flags, data->error);
306 		if (stop)
307 			seq_printf(s,
308 				"CMD%u(0x%x) flg %x rsp %x %x %x %x err %d\n",
309 				stop->opcode, stop->arg, stop->flags,
310 				stop->resp[0], stop->resp[1], stop->resp[2],
311 				stop->resp[3], stop->error);
312 	}
313 
314 	spin_unlock_bh(&slot->host->lock);
315 
316 	return 0;
317 }
318 
319 static int atmci_req_open(struct inode *inode, struct file *file)
320 {
321 	return single_open(file, atmci_req_show, inode->i_private);
322 }
323 
324 static const struct file_operations atmci_req_fops = {
325 	.owner		= THIS_MODULE,
326 	.open		= atmci_req_open,
327 	.read		= seq_read,
328 	.llseek		= seq_lseek,
329 	.release	= single_release,
330 };
331 
332 static void atmci_show_status_reg(struct seq_file *s,
333 		const char *regname, u32 value)
334 {
335 	static const char	*sr_bit[] = {
336 		[0]	= "CMDRDY",
337 		[1]	= "RXRDY",
338 		[2]	= "TXRDY",
339 		[3]	= "BLKE",
340 		[4]	= "DTIP",
341 		[5]	= "NOTBUSY",
342 		[6]	= "ENDRX",
343 		[7]	= "ENDTX",
344 		[8]	= "SDIOIRQA",
345 		[9]	= "SDIOIRQB",
346 		[12]	= "SDIOWAIT",
347 		[14]	= "RXBUFF",
348 		[15]	= "TXBUFE",
349 		[16]	= "RINDE",
350 		[17]	= "RDIRE",
351 		[18]	= "RCRCE",
352 		[19]	= "RENDE",
353 		[20]	= "RTOE",
354 		[21]	= "DCRCE",
355 		[22]	= "DTOE",
356 		[23]	= "CSTOE",
357 		[24]	= "BLKOVRE",
358 		[25]	= "DMADONE",
359 		[26]	= "FIFOEMPTY",
360 		[27]	= "XFRDONE",
361 		[30]	= "OVRE",
362 		[31]	= "UNRE",
363 	};
364 	unsigned int		i;
365 
366 	seq_printf(s, "%s:\t0x%08x", regname, value);
367 	for (i = 0; i < ARRAY_SIZE(sr_bit); i++) {
368 		if (value & (1 << i)) {
369 			if (sr_bit[i])
370 				seq_printf(s, " %s", sr_bit[i]);
371 			else
372 				seq_puts(s, " UNKNOWN");
373 		}
374 	}
375 	seq_putc(s, '\n');
376 }
377 
378 static int atmci_regs_show(struct seq_file *s, void *v)
379 {
380 	struct atmel_mci	*host = s->private;
381 	u32			*buf;
382 	int			ret = 0;
383 
384 
385 	buf = kmalloc(ATMCI_REGS_SIZE, GFP_KERNEL);
386 	if (!buf)
387 		return -ENOMEM;
388 
389 	/*
390 	 * Grab a more or less consistent snapshot. Note that we're
391 	 * not disabling interrupts, so IMR and SR may not be
392 	 * consistent.
393 	 */
394 	ret = clk_prepare_enable(host->mck);
395 	if (ret)
396 		goto out;
397 
398 	spin_lock_bh(&host->lock);
399 	memcpy_fromio(buf, host->regs, ATMCI_REGS_SIZE);
400 	spin_unlock_bh(&host->lock);
401 
402 	clk_disable_unprepare(host->mck);
403 
404 	seq_printf(s, "MR:\t0x%08x%s%s ",
405 			buf[ATMCI_MR / 4],
406 			buf[ATMCI_MR / 4] & ATMCI_MR_RDPROOF ? " RDPROOF" : "",
407 			buf[ATMCI_MR / 4] & ATMCI_MR_WRPROOF ? " WRPROOF" : "");
408 	if (host->caps.has_odd_clk_div)
409 		seq_printf(s, "{CLKDIV,CLKODD}=%u\n",
410 				((buf[ATMCI_MR / 4] & 0xff) << 1)
411 				| ((buf[ATMCI_MR / 4] >> 16) & 1));
412 	else
413 		seq_printf(s, "CLKDIV=%u\n",
414 				(buf[ATMCI_MR / 4] & 0xff));
415 	seq_printf(s, "DTOR:\t0x%08x\n", buf[ATMCI_DTOR / 4]);
416 	seq_printf(s, "SDCR:\t0x%08x\n", buf[ATMCI_SDCR / 4]);
417 	seq_printf(s, "ARGR:\t0x%08x\n", buf[ATMCI_ARGR / 4]);
418 	seq_printf(s, "BLKR:\t0x%08x BCNT=%u BLKLEN=%u\n",
419 			buf[ATMCI_BLKR / 4],
420 			buf[ATMCI_BLKR / 4] & 0xffff,
421 			(buf[ATMCI_BLKR / 4] >> 16) & 0xffff);
422 	if (host->caps.has_cstor_reg)
423 		seq_printf(s, "CSTOR:\t0x%08x\n", buf[ATMCI_CSTOR / 4]);
424 
425 	/* Don't read RSPR and RDR; it will consume the data there */
426 
427 	atmci_show_status_reg(s, "SR", buf[ATMCI_SR / 4]);
428 	atmci_show_status_reg(s, "IMR", buf[ATMCI_IMR / 4]);
429 
430 	if (host->caps.has_dma_conf_reg) {
431 		u32 val;
432 
433 		val = buf[ATMCI_DMA / 4];
434 		seq_printf(s, "DMA:\t0x%08x OFFSET=%u CHKSIZE=%u%s\n",
435 				val, val & 3,
436 				((val >> 4) & 3) ?
437 					1 << (((val >> 4) & 3) + 1) : 1,
438 				val & ATMCI_DMAEN ? " DMAEN" : "");
439 	}
440 	if (host->caps.has_cfg_reg) {
441 		u32 val;
442 
443 		val = buf[ATMCI_CFG / 4];
444 		seq_printf(s, "CFG:\t0x%08x%s%s%s%s\n",
445 				val,
446 				val & ATMCI_CFG_FIFOMODE_1DATA ? " FIFOMODE_ONE_DATA" : "",
447 				val & ATMCI_CFG_FERRCTRL_COR ? " FERRCTRL_CLEAR_ON_READ" : "",
448 				val & ATMCI_CFG_HSMODE ? " HSMODE" : "",
449 				val & ATMCI_CFG_LSYNC ? " LSYNC" : "");
450 	}
451 
452 out:
453 	kfree(buf);
454 
455 	return ret;
456 }
457 
458 static int atmci_regs_open(struct inode *inode, struct file *file)
459 {
460 	return single_open(file, atmci_regs_show, inode->i_private);
461 }
462 
463 static const struct file_operations atmci_regs_fops = {
464 	.owner		= THIS_MODULE,
465 	.open		= atmci_regs_open,
466 	.read		= seq_read,
467 	.llseek		= seq_lseek,
468 	.release	= single_release,
469 };
470 
471 static void atmci_init_debugfs(struct atmel_mci_slot *slot)
472 {
473 	struct mmc_host		*mmc = slot->mmc;
474 	struct atmel_mci	*host = slot->host;
475 	struct dentry		*root;
476 	struct dentry		*node;
477 
478 	root = mmc->debugfs_root;
479 	if (!root)
480 		return;
481 
482 	node = debugfs_create_file("regs", S_IRUSR, root, host,
483 			&atmci_regs_fops);
484 	if (IS_ERR(node))
485 		return;
486 	if (!node)
487 		goto err;
488 
489 	node = debugfs_create_file("req", S_IRUSR, root, slot, &atmci_req_fops);
490 	if (!node)
491 		goto err;
492 
493 	node = debugfs_create_u32("state", S_IRUSR, root, (u32 *)&host->state);
494 	if (!node)
495 		goto err;
496 
497 	node = debugfs_create_x32("pending_events", S_IRUSR, root,
498 				     (u32 *)&host->pending_events);
499 	if (!node)
500 		goto err;
501 
502 	node = debugfs_create_x32("completed_events", S_IRUSR, root,
503 				     (u32 *)&host->completed_events);
504 	if (!node)
505 		goto err;
506 
507 	return;
508 
509 err:
510 	dev_err(&mmc->class_dev, "failed to initialize debugfs for slot\n");
511 }
512 
513 #if defined(CONFIG_OF)
514 static const struct of_device_id atmci_dt_ids[] = {
515 	{ .compatible = "atmel,hsmci" },
516 	{ /* sentinel */ }
517 };
518 
519 MODULE_DEVICE_TABLE(of, atmci_dt_ids);
520 
521 static struct mci_platform_data*
522 atmci_of_init(struct platform_device *pdev)
523 {
524 	struct device_node *np = pdev->dev.of_node;
525 	struct device_node *cnp;
526 	struct mci_platform_data *pdata;
527 	u32 slot_id;
528 
529 	if (!np) {
530 		dev_err(&pdev->dev, "device node not found\n");
531 		return ERR_PTR(-EINVAL);
532 	}
533 
534 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
535 	if (!pdata) {
536 		dev_err(&pdev->dev, "could not allocate memory for pdata\n");
537 		return ERR_PTR(-ENOMEM);
538 	}
539 
540 	for_each_child_of_node(np, cnp) {
541 		if (of_property_read_u32(cnp, "reg", &slot_id)) {
542 			dev_warn(&pdev->dev, "reg property is missing for %s\n",
543 				 cnp->full_name);
544 			continue;
545 		}
546 
547 		if (slot_id >= ATMCI_MAX_NR_SLOTS) {
548 			dev_warn(&pdev->dev, "can't have more than %d slots\n",
549 			         ATMCI_MAX_NR_SLOTS);
550 			break;
551 		}
552 
553 		if (of_property_read_u32(cnp, "bus-width",
554 		                         &pdata->slot[slot_id].bus_width))
555 			pdata->slot[slot_id].bus_width = 1;
556 
557 		pdata->slot[slot_id].detect_pin =
558 			of_get_named_gpio(cnp, "cd-gpios", 0);
559 
560 		pdata->slot[slot_id].detect_is_active_high =
561 			of_property_read_bool(cnp, "cd-inverted");
562 
563 		pdata->slot[slot_id].non_removable =
564 			of_property_read_bool(cnp, "non-removable");
565 
566 		pdata->slot[slot_id].wp_pin =
567 			of_get_named_gpio(cnp, "wp-gpios", 0);
568 	}
569 
570 	return pdata;
571 }
572 #else /* CONFIG_OF */
573 static inline struct mci_platform_data*
574 atmci_of_init(struct platform_device *dev)
575 {
576 	return ERR_PTR(-EINVAL);
577 }
578 #endif
579 
580 static inline unsigned int atmci_get_version(struct atmel_mci *host)
581 {
582 	return atmci_readl(host, ATMCI_VERSION) & 0x00000fff;
583 }
584 
585 static void atmci_timeout_timer(unsigned long data)
586 {
587 	struct atmel_mci *host;
588 
589 	host = (struct atmel_mci *)data;
590 
591 	dev_dbg(&host->pdev->dev, "software timeout\n");
592 
593 	if (host->mrq->cmd->data) {
594 		host->mrq->cmd->data->error = -ETIMEDOUT;
595 		host->data = NULL;
596 		/*
597 		 * With some SDIO modules, sometimes DMA transfer hangs. If
598 		 * stop_transfer() is not called then the DMA request is not
599 		 * removed, following ones are queued and never computed.
600 		 */
601 		if (host->state == STATE_DATA_XFER)
602 			host->stop_transfer(host);
603 	} else {
604 		host->mrq->cmd->error = -ETIMEDOUT;
605 		host->cmd = NULL;
606 	}
607 	host->need_reset = 1;
608 	host->state = STATE_END_REQUEST;
609 	smp_wmb();
610 	tasklet_schedule(&host->tasklet);
611 }
612 
613 static inline unsigned int atmci_ns_to_clocks(struct atmel_mci *host,
614 					unsigned int ns)
615 {
616 	/*
617 	 * It is easier here to use us instead of ns for the timeout,
618 	 * it prevents from overflows during calculation.
619 	 */
620 	unsigned int us = DIV_ROUND_UP(ns, 1000);
621 
622 	/* Maximum clock frequency is host->bus_hz/2 */
623 	return us * (DIV_ROUND_UP(host->bus_hz, 2000000));
624 }
625 
626 static void atmci_set_timeout(struct atmel_mci *host,
627 		struct atmel_mci_slot *slot, struct mmc_data *data)
628 {
629 	static unsigned	dtomul_to_shift[] = {
630 		0, 4, 7, 8, 10, 12, 16, 20
631 	};
632 	unsigned	timeout;
633 	unsigned	dtocyc;
634 	unsigned	dtomul;
635 
636 	timeout = atmci_ns_to_clocks(host, data->timeout_ns)
637 		+ data->timeout_clks;
638 
639 	for (dtomul = 0; dtomul < 8; dtomul++) {
640 		unsigned shift = dtomul_to_shift[dtomul];
641 		dtocyc = (timeout + (1 << shift) - 1) >> shift;
642 		if (dtocyc < 15)
643 			break;
644 	}
645 
646 	if (dtomul >= 8) {
647 		dtomul = 7;
648 		dtocyc = 15;
649 	}
650 
651 	dev_vdbg(&slot->mmc->class_dev, "setting timeout to %u cycles\n",
652 			dtocyc << dtomul_to_shift[dtomul]);
653 	atmci_writel(host, ATMCI_DTOR, (ATMCI_DTOMUL(dtomul) | ATMCI_DTOCYC(dtocyc)));
654 }
655 
656 /*
657  * Return mask with command flags to be enabled for this command.
658  */
659 static u32 atmci_prepare_command(struct mmc_host *mmc,
660 				 struct mmc_command *cmd)
661 {
662 	struct mmc_data	*data;
663 	u32		cmdr;
664 
665 	cmd->error = -EINPROGRESS;
666 
667 	cmdr = ATMCI_CMDR_CMDNB(cmd->opcode);
668 
669 	if (cmd->flags & MMC_RSP_PRESENT) {
670 		if (cmd->flags & MMC_RSP_136)
671 			cmdr |= ATMCI_CMDR_RSPTYP_136BIT;
672 		else
673 			cmdr |= ATMCI_CMDR_RSPTYP_48BIT;
674 	}
675 
676 	/*
677 	 * This should really be MAXLAT_5 for CMD2 and ACMD41, but
678 	 * it's too difficult to determine whether this is an ACMD or
679 	 * not. Better make it 64.
680 	 */
681 	cmdr |= ATMCI_CMDR_MAXLAT_64CYC;
682 
683 	if (mmc->ios.bus_mode == MMC_BUSMODE_OPENDRAIN)
684 		cmdr |= ATMCI_CMDR_OPDCMD;
685 
686 	data = cmd->data;
687 	if (data) {
688 		cmdr |= ATMCI_CMDR_START_XFER;
689 
690 		if (cmd->opcode == SD_IO_RW_EXTENDED) {
691 			cmdr |= ATMCI_CMDR_SDIO_BLOCK;
692 		} else {
693 			if (data->flags & MMC_DATA_STREAM)
694 				cmdr |= ATMCI_CMDR_STREAM;
695 			else if (data->blocks > 1)
696 				cmdr |= ATMCI_CMDR_MULTI_BLOCK;
697 			else
698 				cmdr |= ATMCI_CMDR_BLOCK;
699 		}
700 
701 		if (data->flags & MMC_DATA_READ)
702 			cmdr |= ATMCI_CMDR_TRDIR_READ;
703 	}
704 
705 	return cmdr;
706 }
707 
708 static void atmci_send_command(struct atmel_mci *host,
709 		struct mmc_command *cmd, u32 cmd_flags)
710 {
711 	WARN_ON(host->cmd);
712 	host->cmd = cmd;
713 
714 	dev_vdbg(&host->pdev->dev,
715 			"start command: ARGR=0x%08x CMDR=0x%08x\n",
716 			cmd->arg, cmd_flags);
717 
718 	atmci_writel(host, ATMCI_ARGR, cmd->arg);
719 	atmci_writel(host, ATMCI_CMDR, cmd_flags);
720 }
721 
722 static void atmci_send_stop_cmd(struct atmel_mci *host, struct mmc_data *data)
723 {
724 	dev_dbg(&host->pdev->dev, "send stop command\n");
725 	atmci_send_command(host, data->stop, host->stop_cmdr);
726 	atmci_writel(host, ATMCI_IER, ATMCI_CMDRDY);
727 }
728 
729 /*
730  * Configure given PDC buffer taking care of alignement issues.
731  * Update host->data_size and host->sg.
732  */
733 static void atmci_pdc_set_single_buf(struct atmel_mci *host,
734 	enum atmci_xfer_dir dir, enum atmci_pdc_buf buf_nb)
735 {
736 	u32 pointer_reg, counter_reg;
737 	unsigned int buf_size;
738 
739 	if (dir == XFER_RECEIVE) {
740 		pointer_reg = ATMEL_PDC_RPR;
741 		counter_reg = ATMEL_PDC_RCR;
742 	} else {
743 		pointer_reg = ATMEL_PDC_TPR;
744 		counter_reg = ATMEL_PDC_TCR;
745 	}
746 
747 	if (buf_nb == PDC_SECOND_BUF) {
748 		pointer_reg += ATMEL_PDC_SCND_BUF_OFF;
749 		counter_reg += ATMEL_PDC_SCND_BUF_OFF;
750 	}
751 
752 	if (!host->caps.has_rwproof) {
753 		buf_size = host->buf_size;
754 		atmci_writel(host, pointer_reg, host->buf_phys_addr);
755 	} else {
756 		buf_size = sg_dma_len(host->sg);
757 		atmci_writel(host, pointer_reg, sg_dma_address(host->sg));
758 	}
759 
760 	if (host->data_size <= buf_size) {
761 		if (host->data_size & 0x3) {
762 			/* If size is different from modulo 4, transfer bytes */
763 			atmci_writel(host, counter_reg, host->data_size);
764 			atmci_writel(host, ATMCI_MR, host->mode_reg | ATMCI_MR_PDCFBYTE);
765 		} else {
766 			/* Else transfer 32-bits words */
767 			atmci_writel(host, counter_reg, host->data_size / 4);
768 		}
769 		host->data_size = 0;
770 	} else {
771 		/* We assume the size of a page is 32-bits aligned */
772 		atmci_writel(host, counter_reg, sg_dma_len(host->sg) / 4);
773 		host->data_size -= sg_dma_len(host->sg);
774 		if (host->data_size)
775 			host->sg = sg_next(host->sg);
776 	}
777 }
778 
779 /*
780  * Configure PDC buffer according to the data size ie configuring one or two
781  * buffers. Don't use this function if you want to configure only the second
782  * buffer. In this case, use atmci_pdc_set_single_buf.
783  */
784 static void atmci_pdc_set_both_buf(struct atmel_mci *host, int dir)
785 {
786 	atmci_pdc_set_single_buf(host, dir, PDC_FIRST_BUF);
787 	if (host->data_size)
788 		atmci_pdc_set_single_buf(host, dir, PDC_SECOND_BUF);
789 }
790 
791 /*
792  * Unmap sg lists, called when transfer is finished.
793  */
794 static void atmci_pdc_cleanup(struct atmel_mci *host)
795 {
796 	struct mmc_data         *data = host->data;
797 
798 	if (data)
799 		dma_unmap_sg(&host->pdev->dev,
800 				data->sg, data->sg_len,
801 				((data->flags & MMC_DATA_WRITE)
802 				 ? DMA_TO_DEVICE : DMA_FROM_DEVICE));
803 }
804 
805 /*
806  * Disable PDC transfers. Update pending flags to EVENT_XFER_COMPLETE after
807  * having received ATMCI_TXBUFE or ATMCI_RXBUFF interrupt. Enable ATMCI_NOTBUSY
808  * interrupt needed for both transfer directions.
809  */
810 static void atmci_pdc_complete(struct atmel_mci *host)
811 {
812 	int transfer_size = host->data->blocks * host->data->blksz;
813 	int i;
814 
815 	atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
816 
817 	if ((!host->caps.has_rwproof)
818 	    && (host->data->flags & MMC_DATA_READ)) {
819 		if (host->caps.has_bad_data_ordering)
820 			for (i = 0; i < transfer_size; i++)
821 				host->buffer[i] = swab32(host->buffer[i]);
822 		sg_copy_from_buffer(host->data->sg, host->data->sg_len,
823 		                    host->buffer, transfer_size);
824 	}
825 
826 	atmci_pdc_cleanup(host);
827 
828 	dev_dbg(&host->pdev->dev, "(%s) set pending xfer complete\n", __func__);
829 	atmci_set_pending(host, EVENT_XFER_COMPLETE);
830 	tasklet_schedule(&host->tasklet);
831 }
832 
833 static void atmci_dma_cleanup(struct atmel_mci *host)
834 {
835 	struct mmc_data                 *data = host->data;
836 
837 	if (data)
838 		dma_unmap_sg(host->dma.chan->device->dev,
839 				data->sg, data->sg_len,
840 				((data->flags & MMC_DATA_WRITE)
841 				 ? DMA_TO_DEVICE : DMA_FROM_DEVICE));
842 }
843 
844 /*
845  * This function is called by the DMA driver from tasklet context.
846  */
847 static void atmci_dma_complete(void *arg)
848 {
849 	struct atmel_mci	*host = arg;
850 	struct mmc_data		*data = host->data;
851 
852 	dev_vdbg(&host->pdev->dev, "DMA complete\n");
853 
854 	if (host->caps.has_dma_conf_reg)
855 		/* Disable DMA hardware handshaking on MCI */
856 		atmci_writel(host, ATMCI_DMA, atmci_readl(host, ATMCI_DMA) & ~ATMCI_DMAEN);
857 
858 	atmci_dma_cleanup(host);
859 
860 	/*
861 	 * If the card was removed, data will be NULL. No point trying
862 	 * to send the stop command or waiting for NBUSY in this case.
863 	 */
864 	if (data) {
865 		dev_dbg(&host->pdev->dev,
866 		        "(%s) set pending xfer complete\n", __func__);
867 		atmci_set_pending(host, EVENT_XFER_COMPLETE);
868 		tasklet_schedule(&host->tasklet);
869 
870 		/*
871 		 * Regardless of what the documentation says, we have
872 		 * to wait for NOTBUSY even after block read
873 		 * operations.
874 		 *
875 		 * When the DMA transfer is complete, the controller
876 		 * may still be reading the CRC from the card, i.e.
877 		 * the data transfer is still in progress and we
878 		 * haven't seen all the potential error bits yet.
879 		 *
880 		 * The interrupt handler will schedule a different
881 		 * tasklet to finish things up when the data transfer
882 		 * is completely done.
883 		 *
884 		 * We may not complete the mmc request here anyway
885 		 * because the mmc layer may call back and cause us to
886 		 * violate the "don't submit new operations from the
887 		 * completion callback" rule of the dma engine
888 		 * framework.
889 		 */
890 		atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
891 	}
892 }
893 
894 /*
895  * Returns a mask of interrupt flags to be enabled after the whole
896  * request has been prepared.
897  */
898 static u32 atmci_prepare_data(struct atmel_mci *host, struct mmc_data *data)
899 {
900 	u32 iflags;
901 
902 	data->error = -EINPROGRESS;
903 
904 	host->sg = data->sg;
905 	host->sg_len = data->sg_len;
906 	host->data = data;
907 	host->data_chan = NULL;
908 
909 	iflags = ATMCI_DATA_ERROR_FLAGS;
910 
911 	/*
912 	 * Errata: MMC data write operation with less than 12
913 	 * bytes is impossible.
914 	 *
915 	 * Errata: MCI Transmit Data Register (TDR) FIFO
916 	 * corruption when length is not multiple of 4.
917 	 */
918 	if (data->blocks * data->blksz < 12
919 			|| (data->blocks * data->blksz) & 3)
920 		host->need_reset = true;
921 
922 	host->pio_offset = 0;
923 	if (data->flags & MMC_DATA_READ)
924 		iflags |= ATMCI_RXRDY;
925 	else
926 		iflags |= ATMCI_TXRDY;
927 
928 	return iflags;
929 }
930 
931 /*
932  * Set interrupt flags and set block length into the MCI mode register even
933  * if this value is also accessible in the MCI block register. It seems to be
934  * necessary before the High Speed MCI version. It also map sg and configure
935  * PDC registers.
936  */
937 static u32
938 atmci_prepare_data_pdc(struct atmel_mci *host, struct mmc_data *data)
939 {
940 	u32 iflags, tmp;
941 	unsigned int sg_len;
942 	enum dma_data_direction dir;
943 	int i;
944 
945 	data->error = -EINPROGRESS;
946 
947 	host->data = data;
948 	host->sg = data->sg;
949 	iflags = ATMCI_DATA_ERROR_FLAGS;
950 
951 	/* Enable pdc mode */
952 	atmci_writel(host, ATMCI_MR, host->mode_reg | ATMCI_MR_PDCMODE);
953 
954 	if (data->flags & MMC_DATA_READ) {
955 		dir = DMA_FROM_DEVICE;
956 		iflags |= ATMCI_ENDRX | ATMCI_RXBUFF;
957 	} else {
958 		dir = DMA_TO_DEVICE;
959 		iflags |= ATMCI_ENDTX | ATMCI_TXBUFE | ATMCI_BLKE;
960 	}
961 
962 	/* Set BLKLEN */
963 	tmp = atmci_readl(host, ATMCI_MR);
964 	tmp &= 0x0000ffff;
965 	tmp |= ATMCI_BLKLEN(data->blksz);
966 	atmci_writel(host, ATMCI_MR, tmp);
967 
968 	/* Configure PDC */
969 	host->data_size = data->blocks * data->blksz;
970 	sg_len = dma_map_sg(&host->pdev->dev, data->sg, data->sg_len, dir);
971 
972 	if ((!host->caps.has_rwproof)
973 	    && (host->data->flags & MMC_DATA_WRITE)) {
974 		sg_copy_to_buffer(host->data->sg, host->data->sg_len,
975 		                  host->buffer, host->data_size);
976 		if (host->caps.has_bad_data_ordering)
977 			for (i = 0; i < host->data_size; i++)
978 				host->buffer[i] = swab32(host->buffer[i]);
979 	}
980 
981 	if (host->data_size)
982 		atmci_pdc_set_both_buf(host,
983 			((dir == DMA_FROM_DEVICE) ? XFER_RECEIVE : XFER_TRANSMIT));
984 
985 	return iflags;
986 }
987 
988 static u32
989 atmci_prepare_data_dma(struct atmel_mci *host, struct mmc_data *data)
990 {
991 	struct dma_chan			*chan;
992 	struct dma_async_tx_descriptor	*desc;
993 	struct scatterlist		*sg;
994 	unsigned int			i;
995 	enum dma_data_direction		direction;
996 	enum dma_transfer_direction	slave_dirn;
997 	unsigned int			sglen;
998 	u32				maxburst;
999 	u32 iflags;
1000 
1001 	data->error = -EINPROGRESS;
1002 
1003 	WARN_ON(host->data);
1004 	host->sg = NULL;
1005 	host->data = data;
1006 
1007 	iflags = ATMCI_DATA_ERROR_FLAGS;
1008 
1009 	/*
1010 	 * We don't do DMA on "complex" transfers, i.e. with
1011 	 * non-word-aligned buffers or lengths. Also, we don't bother
1012 	 * with all the DMA setup overhead for short transfers.
1013 	 */
1014 	if (data->blocks * data->blksz < ATMCI_DMA_THRESHOLD)
1015 		return atmci_prepare_data(host, data);
1016 	if (data->blksz & 3)
1017 		return atmci_prepare_data(host, data);
1018 
1019 	for_each_sg(data->sg, sg, data->sg_len, i) {
1020 		if (sg->offset & 3 || sg->length & 3)
1021 			return atmci_prepare_data(host, data);
1022 	}
1023 
1024 	/* If we don't have a channel, we can't do DMA */
1025 	chan = host->dma.chan;
1026 	if (chan)
1027 		host->data_chan = chan;
1028 
1029 	if (!chan)
1030 		return -ENODEV;
1031 
1032 	if (data->flags & MMC_DATA_READ) {
1033 		direction = DMA_FROM_DEVICE;
1034 		host->dma_conf.direction = slave_dirn = DMA_DEV_TO_MEM;
1035 		maxburst = atmci_convert_chksize(host->dma_conf.src_maxburst);
1036 	} else {
1037 		direction = DMA_TO_DEVICE;
1038 		host->dma_conf.direction = slave_dirn = DMA_MEM_TO_DEV;
1039 		maxburst = atmci_convert_chksize(host->dma_conf.dst_maxburst);
1040 	}
1041 
1042 	if (host->caps.has_dma_conf_reg)
1043 		atmci_writel(host, ATMCI_DMA, ATMCI_DMA_CHKSIZE(maxburst) |
1044 			ATMCI_DMAEN);
1045 
1046 	sglen = dma_map_sg(chan->device->dev, data->sg,
1047 			data->sg_len, direction);
1048 
1049 	dmaengine_slave_config(chan, &host->dma_conf);
1050 	desc = dmaengine_prep_slave_sg(chan,
1051 			data->sg, sglen, slave_dirn,
1052 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1053 	if (!desc)
1054 		goto unmap_exit;
1055 
1056 	host->dma.data_desc = desc;
1057 	desc->callback = atmci_dma_complete;
1058 	desc->callback_param = host;
1059 
1060 	return iflags;
1061 unmap_exit:
1062 	dma_unmap_sg(chan->device->dev, data->sg, data->sg_len, direction);
1063 	return -ENOMEM;
1064 }
1065 
1066 static void
1067 atmci_submit_data(struct atmel_mci *host, struct mmc_data *data)
1068 {
1069 	return;
1070 }
1071 
1072 /*
1073  * Start PDC according to transfer direction.
1074  */
1075 static void
1076 atmci_submit_data_pdc(struct atmel_mci *host, struct mmc_data *data)
1077 {
1078 	if (data->flags & MMC_DATA_READ)
1079 		atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTEN);
1080 	else
1081 		atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN);
1082 }
1083 
1084 static void
1085 atmci_submit_data_dma(struct atmel_mci *host, struct mmc_data *data)
1086 {
1087 	struct dma_chan			*chan = host->data_chan;
1088 	struct dma_async_tx_descriptor	*desc = host->dma.data_desc;
1089 
1090 	if (chan) {
1091 		dmaengine_submit(desc);
1092 		dma_async_issue_pending(chan);
1093 	}
1094 }
1095 
1096 static void atmci_stop_transfer(struct atmel_mci *host)
1097 {
1098 	dev_dbg(&host->pdev->dev,
1099 	        "(%s) set pending xfer complete\n", __func__);
1100 	atmci_set_pending(host, EVENT_XFER_COMPLETE);
1101 	atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1102 }
1103 
1104 /*
1105  * Stop data transfer because error(s) occurred.
1106  */
1107 static void atmci_stop_transfer_pdc(struct atmel_mci *host)
1108 {
1109 	atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
1110 }
1111 
1112 static void atmci_stop_transfer_dma(struct atmel_mci *host)
1113 {
1114 	struct dma_chan *chan = host->data_chan;
1115 
1116 	if (chan) {
1117 		dmaengine_terminate_all(chan);
1118 		atmci_dma_cleanup(host);
1119 	} else {
1120 		/* Data transfer was stopped by the interrupt handler */
1121 		dev_dbg(&host->pdev->dev,
1122 		        "(%s) set pending xfer complete\n", __func__);
1123 		atmci_set_pending(host, EVENT_XFER_COMPLETE);
1124 		atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1125 	}
1126 }
1127 
1128 /*
1129  * Start a request: prepare data if needed, prepare the command and activate
1130  * interrupts.
1131  */
1132 static void atmci_start_request(struct atmel_mci *host,
1133 		struct atmel_mci_slot *slot)
1134 {
1135 	struct mmc_request	*mrq;
1136 	struct mmc_command	*cmd;
1137 	struct mmc_data		*data;
1138 	u32			iflags;
1139 	u32			cmdflags;
1140 
1141 	mrq = slot->mrq;
1142 	host->cur_slot = slot;
1143 	host->mrq = mrq;
1144 
1145 	host->pending_events = 0;
1146 	host->completed_events = 0;
1147 	host->cmd_status = 0;
1148 	host->data_status = 0;
1149 
1150 	dev_dbg(&host->pdev->dev, "start request: cmd %u\n", mrq->cmd->opcode);
1151 
1152 	if (host->need_reset || host->caps.need_reset_after_xfer) {
1153 		iflags = atmci_readl(host, ATMCI_IMR);
1154 		iflags &= (ATMCI_SDIOIRQA | ATMCI_SDIOIRQB);
1155 		atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
1156 		atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
1157 		atmci_writel(host, ATMCI_MR, host->mode_reg);
1158 		if (host->caps.has_cfg_reg)
1159 			atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1160 		atmci_writel(host, ATMCI_IER, iflags);
1161 		host->need_reset = false;
1162 	}
1163 	atmci_writel(host, ATMCI_SDCR, slot->sdc_reg);
1164 
1165 	iflags = atmci_readl(host, ATMCI_IMR);
1166 	if (iflags & ~(ATMCI_SDIOIRQA | ATMCI_SDIOIRQB))
1167 		dev_dbg(&slot->mmc->class_dev, "WARNING: IMR=0x%08x\n",
1168 				iflags);
1169 
1170 	if (unlikely(test_and_clear_bit(ATMCI_CARD_NEED_INIT, &slot->flags))) {
1171 		/* Send init sequence (74 clock cycles) */
1172 		atmci_writel(host, ATMCI_CMDR, ATMCI_CMDR_SPCMD_INIT);
1173 		while (!(atmci_readl(host, ATMCI_SR) & ATMCI_CMDRDY))
1174 			cpu_relax();
1175 	}
1176 	iflags = 0;
1177 	data = mrq->data;
1178 	if (data) {
1179 		atmci_set_timeout(host, slot, data);
1180 
1181 		/* Must set block count/size before sending command */
1182 		atmci_writel(host, ATMCI_BLKR, ATMCI_BCNT(data->blocks)
1183 				| ATMCI_BLKLEN(data->blksz));
1184 		dev_vdbg(&slot->mmc->class_dev, "BLKR=0x%08x\n",
1185 			ATMCI_BCNT(data->blocks) | ATMCI_BLKLEN(data->blksz));
1186 
1187 		iflags |= host->prepare_data(host, data);
1188 	}
1189 
1190 	iflags |= ATMCI_CMDRDY;
1191 	cmd = mrq->cmd;
1192 	cmdflags = atmci_prepare_command(slot->mmc, cmd);
1193 
1194 	/*
1195 	 * DMA transfer should be started before sending the command to avoid
1196 	 * unexpected errors especially for read operations in SDIO mode.
1197 	 * Unfortunately, in PDC mode, command has to be sent before starting
1198 	 * the transfer.
1199 	 */
1200 	if (host->submit_data != &atmci_submit_data_dma)
1201 		atmci_send_command(host, cmd, cmdflags);
1202 
1203 	if (data)
1204 		host->submit_data(host, data);
1205 
1206 	if (host->submit_data == &atmci_submit_data_dma)
1207 		atmci_send_command(host, cmd, cmdflags);
1208 
1209 	if (mrq->stop) {
1210 		host->stop_cmdr = atmci_prepare_command(slot->mmc, mrq->stop);
1211 		host->stop_cmdr |= ATMCI_CMDR_STOP_XFER;
1212 		if (!(data->flags & MMC_DATA_WRITE))
1213 			host->stop_cmdr |= ATMCI_CMDR_TRDIR_READ;
1214 		if (data->flags & MMC_DATA_STREAM)
1215 			host->stop_cmdr |= ATMCI_CMDR_STREAM;
1216 		else
1217 			host->stop_cmdr |= ATMCI_CMDR_MULTI_BLOCK;
1218 	}
1219 
1220 	/*
1221 	 * We could have enabled interrupts earlier, but I suspect
1222 	 * that would open up a nice can of interesting race
1223 	 * conditions (e.g. command and data complete, but stop not
1224 	 * prepared yet.)
1225 	 */
1226 	atmci_writel(host, ATMCI_IER, iflags);
1227 
1228 	mod_timer(&host->timer, jiffies +  msecs_to_jiffies(2000));
1229 }
1230 
1231 static void atmci_queue_request(struct atmel_mci *host,
1232 		struct atmel_mci_slot *slot, struct mmc_request *mrq)
1233 {
1234 	dev_vdbg(&slot->mmc->class_dev, "queue request: state=%d\n",
1235 			host->state);
1236 
1237 	spin_lock_bh(&host->lock);
1238 	slot->mrq = mrq;
1239 	if (host->state == STATE_IDLE) {
1240 		host->state = STATE_SENDING_CMD;
1241 		atmci_start_request(host, slot);
1242 	} else {
1243 		dev_dbg(&host->pdev->dev, "queue request\n");
1244 		list_add_tail(&slot->queue_node, &host->queue);
1245 	}
1246 	spin_unlock_bh(&host->lock);
1247 }
1248 
1249 static void atmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
1250 {
1251 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1252 	struct atmel_mci	*host = slot->host;
1253 	struct mmc_data		*data;
1254 
1255 	WARN_ON(slot->mrq);
1256 	dev_dbg(&host->pdev->dev, "MRQ: cmd %u\n", mrq->cmd->opcode);
1257 
1258 	/*
1259 	 * We may "know" the card is gone even though there's still an
1260 	 * electrical connection. If so, we really need to communicate
1261 	 * this to the MMC core since there won't be any more
1262 	 * interrupts as the card is completely removed. Otherwise,
1263 	 * the MMC core might believe the card is still there even
1264 	 * though the card was just removed very slowly.
1265 	 */
1266 	if (!test_bit(ATMCI_CARD_PRESENT, &slot->flags)) {
1267 		mrq->cmd->error = -ENOMEDIUM;
1268 		mmc_request_done(mmc, mrq);
1269 		return;
1270 	}
1271 
1272 	/* We don't support multiple blocks of weird lengths. */
1273 	data = mrq->data;
1274 	if (data && data->blocks > 1 && data->blksz & 3) {
1275 		mrq->cmd->error = -EINVAL;
1276 		mmc_request_done(mmc, mrq);
1277 	}
1278 
1279 	atmci_queue_request(host, slot, mrq);
1280 }
1281 
1282 static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
1283 {
1284 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1285 	struct atmel_mci	*host = slot->host;
1286 	unsigned int		i;
1287 	bool			unprepare_clk;
1288 
1289 	slot->sdc_reg &= ~ATMCI_SDCBUS_MASK;
1290 	switch (ios->bus_width) {
1291 	case MMC_BUS_WIDTH_1:
1292 		slot->sdc_reg |= ATMCI_SDCBUS_1BIT;
1293 		break;
1294 	case MMC_BUS_WIDTH_4:
1295 		slot->sdc_reg |= ATMCI_SDCBUS_4BIT;
1296 		break;
1297 	}
1298 
1299 	if (ios->clock) {
1300 		unsigned int clock_min = ~0U;
1301 		u32 clkdiv;
1302 
1303 		clk_prepare(host->mck);
1304 		unprepare_clk = true;
1305 
1306 		spin_lock_bh(&host->lock);
1307 		if (!host->mode_reg) {
1308 			clk_enable(host->mck);
1309 			unprepare_clk = false;
1310 			atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
1311 			atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
1312 			if (host->caps.has_cfg_reg)
1313 				atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1314 		}
1315 
1316 		/*
1317 		 * Use mirror of ios->clock to prevent race with mmc
1318 		 * core ios update when finding the minimum.
1319 		 */
1320 		slot->clock = ios->clock;
1321 		for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
1322 			if (host->slot[i] && host->slot[i]->clock
1323 					&& host->slot[i]->clock < clock_min)
1324 				clock_min = host->slot[i]->clock;
1325 		}
1326 
1327 		/* Calculate clock divider */
1328 		if (host->caps.has_odd_clk_div) {
1329 			clkdiv = DIV_ROUND_UP(host->bus_hz, clock_min) - 2;
1330 			if (clkdiv > 511) {
1331 				dev_warn(&mmc->class_dev,
1332 				         "clock %u too slow; using %lu\n",
1333 				         clock_min, host->bus_hz / (511 + 2));
1334 				clkdiv = 511;
1335 			}
1336 			host->mode_reg = ATMCI_MR_CLKDIV(clkdiv >> 1)
1337 			                 | ATMCI_MR_CLKODD(clkdiv & 1);
1338 		} else {
1339 			clkdiv = DIV_ROUND_UP(host->bus_hz, 2 * clock_min) - 1;
1340 			if (clkdiv > 255) {
1341 				dev_warn(&mmc->class_dev,
1342 				         "clock %u too slow; using %lu\n",
1343 				         clock_min, host->bus_hz / (2 * 256));
1344 				clkdiv = 255;
1345 			}
1346 			host->mode_reg = ATMCI_MR_CLKDIV(clkdiv);
1347 		}
1348 
1349 		/*
1350 		 * WRPROOF and RDPROOF prevent overruns/underruns by
1351 		 * stopping the clock when the FIFO is full/empty.
1352 		 * This state is not expected to last for long.
1353 		 */
1354 		if (host->caps.has_rwproof)
1355 			host->mode_reg |= (ATMCI_MR_WRPROOF | ATMCI_MR_RDPROOF);
1356 
1357 		if (host->caps.has_cfg_reg) {
1358 			/* setup High Speed mode in relation with card capacity */
1359 			if (ios->timing == MMC_TIMING_SD_HS)
1360 				host->cfg_reg |= ATMCI_CFG_HSMODE;
1361 			else
1362 				host->cfg_reg &= ~ATMCI_CFG_HSMODE;
1363 		}
1364 
1365 		if (list_empty(&host->queue)) {
1366 			atmci_writel(host, ATMCI_MR, host->mode_reg);
1367 			if (host->caps.has_cfg_reg)
1368 				atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1369 		} else {
1370 			host->need_clock_update = true;
1371 		}
1372 
1373 		spin_unlock_bh(&host->lock);
1374 	} else {
1375 		bool any_slot_active = false;
1376 
1377 		unprepare_clk = false;
1378 
1379 		spin_lock_bh(&host->lock);
1380 		slot->clock = 0;
1381 		for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
1382 			if (host->slot[i] && host->slot[i]->clock) {
1383 				any_slot_active = true;
1384 				break;
1385 			}
1386 		}
1387 		if (!any_slot_active) {
1388 			atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIDIS);
1389 			if (host->mode_reg) {
1390 				atmci_readl(host, ATMCI_MR);
1391 				clk_disable(host->mck);
1392 				unprepare_clk = true;
1393 			}
1394 			host->mode_reg = 0;
1395 		}
1396 		spin_unlock_bh(&host->lock);
1397 	}
1398 
1399 	if (unprepare_clk)
1400 		clk_unprepare(host->mck);
1401 
1402 	switch (ios->power_mode) {
1403 	case MMC_POWER_OFF:
1404 		if (!IS_ERR(mmc->supply.vmmc))
1405 			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, 0);
1406 		break;
1407 	case MMC_POWER_UP:
1408 		set_bit(ATMCI_CARD_NEED_INIT, &slot->flags);
1409 		if (!IS_ERR(mmc->supply.vmmc))
1410 			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, ios->vdd);
1411 		break;
1412 	default:
1413 		/*
1414 		 * TODO: None of the currently available AVR32-based
1415 		 * boards allow MMC power to be turned off. Implement
1416 		 * power control when this can be tested properly.
1417 		 *
1418 		 * We also need to hook this into the clock management
1419 		 * somehow so that newly inserted cards aren't
1420 		 * subjected to a fast clock before we have a chance
1421 		 * to figure out what the maximum rate is. Currently,
1422 		 * there's no way to avoid this, and there never will
1423 		 * be for boards that don't support power control.
1424 		 */
1425 		break;
1426 	}
1427 }
1428 
1429 static int atmci_get_ro(struct mmc_host *mmc)
1430 {
1431 	int			read_only = -ENOSYS;
1432 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1433 
1434 	if (gpio_is_valid(slot->wp_pin)) {
1435 		read_only = gpio_get_value(slot->wp_pin);
1436 		dev_dbg(&mmc->class_dev, "card is %s\n",
1437 				read_only ? "read-only" : "read-write");
1438 	}
1439 
1440 	return read_only;
1441 }
1442 
1443 static int atmci_get_cd(struct mmc_host *mmc)
1444 {
1445 	int			present = -ENOSYS;
1446 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1447 
1448 	if (gpio_is_valid(slot->detect_pin)) {
1449 		present = !(gpio_get_value(slot->detect_pin) ^
1450 			    slot->detect_is_active_high);
1451 		dev_dbg(&mmc->class_dev, "card is %spresent\n",
1452 				present ? "" : "not ");
1453 	}
1454 
1455 	return present;
1456 }
1457 
1458 static void atmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
1459 {
1460 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1461 	struct atmel_mci	*host = slot->host;
1462 
1463 	if (enable)
1464 		atmci_writel(host, ATMCI_IER, slot->sdio_irq);
1465 	else
1466 		atmci_writel(host, ATMCI_IDR, slot->sdio_irq);
1467 }
1468 
1469 static const struct mmc_host_ops atmci_ops = {
1470 	.request	= atmci_request,
1471 	.set_ios	= atmci_set_ios,
1472 	.get_ro		= atmci_get_ro,
1473 	.get_cd		= atmci_get_cd,
1474 	.enable_sdio_irq = atmci_enable_sdio_irq,
1475 };
1476 
1477 /* Called with host->lock held */
1478 static void atmci_request_end(struct atmel_mci *host, struct mmc_request *mrq)
1479 	__releases(&host->lock)
1480 	__acquires(&host->lock)
1481 {
1482 	struct atmel_mci_slot	*slot = NULL;
1483 	struct mmc_host		*prev_mmc = host->cur_slot->mmc;
1484 
1485 	WARN_ON(host->cmd || host->data);
1486 
1487 	/*
1488 	 * Update the MMC clock rate if necessary. This may be
1489 	 * necessary if set_ios() is called when a different slot is
1490 	 * busy transferring data.
1491 	 */
1492 	if (host->need_clock_update) {
1493 		atmci_writel(host, ATMCI_MR, host->mode_reg);
1494 		if (host->caps.has_cfg_reg)
1495 			atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1496 	}
1497 
1498 	host->cur_slot->mrq = NULL;
1499 	host->mrq = NULL;
1500 	if (!list_empty(&host->queue)) {
1501 		slot = list_entry(host->queue.next,
1502 				struct atmel_mci_slot, queue_node);
1503 		list_del(&slot->queue_node);
1504 		dev_vdbg(&host->pdev->dev, "list not empty: %s is next\n",
1505 				mmc_hostname(slot->mmc));
1506 		host->state = STATE_SENDING_CMD;
1507 		atmci_start_request(host, slot);
1508 	} else {
1509 		dev_vdbg(&host->pdev->dev, "list empty\n");
1510 		host->state = STATE_IDLE;
1511 	}
1512 
1513 	del_timer(&host->timer);
1514 
1515 	spin_unlock(&host->lock);
1516 	mmc_request_done(prev_mmc, mrq);
1517 	spin_lock(&host->lock);
1518 }
1519 
1520 static void atmci_command_complete(struct atmel_mci *host,
1521 			struct mmc_command *cmd)
1522 {
1523 	u32		status = host->cmd_status;
1524 
1525 	/* Read the response from the card (up to 16 bytes) */
1526 	cmd->resp[0] = atmci_readl(host, ATMCI_RSPR);
1527 	cmd->resp[1] = atmci_readl(host, ATMCI_RSPR);
1528 	cmd->resp[2] = atmci_readl(host, ATMCI_RSPR);
1529 	cmd->resp[3] = atmci_readl(host, ATMCI_RSPR);
1530 
1531 	if (status & ATMCI_RTOE)
1532 		cmd->error = -ETIMEDOUT;
1533 	else if ((cmd->flags & MMC_RSP_CRC) && (status & ATMCI_RCRCE))
1534 		cmd->error = -EILSEQ;
1535 	else if (status & (ATMCI_RINDE | ATMCI_RDIRE | ATMCI_RENDE))
1536 		cmd->error = -EIO;
1537 	else if (host->mrq->data && (host->mrq->data->blksz & 3)) {
1538 		if (host->caps.need_blksz_mul_4) {
1539 			cmd->error = -EINVAL;
1540 			host->need_reset = 1;
1541 		}
1542 	} else
1543 		cmd->error = 0;
1544 }
1545 
1546 static void atmci_detect_change(unsigned long data)
1547 {
1548 	struct atmel_mci_slot	*slot = (struct atmel_mci_slot *)data;
1549 	bool			present;
1550 	bool			present_old;
1551 
1552 	/*
1553 	 * atmci_cleanup_slot() sets the ATMCI_SHUTDOWN flag before
1554 	 * freeing the interrupt. We must not re-enable the interrupt
1555 	 * if it has been freed, and if we're shutting down, it
1556 	 * doesn't really matter whether the card is present or not.
1557 	 */
1558 	smp_rmb();
1559 	if (test_bit(ATMCI_SHUTDOWN, &slot->flags))
1560 		return;
1561 
1562 	enable_irq(gpio_to_irq(slot->detect_pin));
1563 	present = !(gpio_get_value(slot->detect_pin) ^
1564 		    slot->detect_is_active_high);
1565 	present_old = test_bit(ATMCI_CARD_PRESENT, &slot->flags);
1566 
1567 	dev_vdbg(&slot->mmc->class_dev, "detect change: %d (was %d)\n",
1568 			present, present_old);
1569 
1570 	if (present != present_old) {
1571 		struct atmel_mci	*host = slot->host;
1572 		struct mmc_request	*mrq;
1573 
1574 		dev_dbg(&slot->mmc->class_dev, "card %s\n",
1575 			present ? "inserted" : "removed");
1576 
1577 		spin_lock(&host->lock);
1578 
1579 		if (!present)
1580 			clear_bit(ATMCI_CARD_PRESENT, &slot->flags);
1581 		else
1582 			set_bit(ATMCI_CARD_PRESENT, &slot->flags);
1583 
1584 		/* Clean up queue if present */
1585 		mrq = slot->mrq;
1586 		if (mrq) {
1587 			if (mrq == host->mrq) {
1588 				/*
1589 				 * Reset controller to terminate any ongoing
1590 				 * commands or data transfers.
1591 				 */
1592 				atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
1593 				atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
1594 				atmci_writel(host, ATMCI_MR, host->mode_reg);
1595 				if (host->caps.has_cfg_reg)
1596 					atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1597 
1598 				host->data = NULL;
1599 				host->cmd = NULL;
1600 
1601 				switch (host->state) {
1602 				case STATE_IDLE:
1603 					break;
1604 				case STATE_SENDING_CMD:
1605 					mrq->cmd->error = -ENOMEDIUM;
1606 					if (mrq->data)
1607 						host->stop_transfer(host);
1608 					break;
1609 				case STATE_DATA_XFER:
1610 					mrq->data->error = -ENOMEDIUM;
1611 					host->stop_transfer(host);
1612 					break;
1613 				case STATE_WAITING_NOTBUSY:
1614 					mrq->data->error = -ENOMEDIUM;
1615 					break;
1616 				case STATE_SENDING_STOP:
1617 					mrq->stop->error = -ENOMEDIUM;
1618 					break;
1619 				case STATE_END_REQUEST:
1620 					break;
1621 				}
1622 
1623 				atmci_request_end(host, mrq);
1624 			} else {
1625 				list_del(&slot->queue_node);
1626 				mrq->cmd->error = -ENOMEDIUM;
1627 				if (mrq->data)
1628 					mrq->data->error = -ENOMEDIUM;
1629 				if (mrq->stop)
1630 					mrq->stop->error = -ENOMEDIUM;
1631 
1632 				spin_unlock(&host->lock);
1633 				mmc_request_done(slot->mmc, mrq);
1634 				spin_lock(&host->lock);
1635 			}
1636 		}
1637 		spin_unlock(&host->lock);
1638 
1639 		mmc_detect_change(slot->mmc, 0);
1640 	}
1641 }
1642 
1643 static void atmci_tasklet_func(unsigned long priv)
1644 {
1645 	struct atmel_mci	*host = (struct atmel_mci *)priv;
1646 	struct mmc_request	*mrq = host->mrq;
1647 	struct mmc_data		*data = host->data;
1648 	enum atmel_mci_state	state = host->state;
1649 	enum atmel_mci_state	prev_state;
1650 	u32			status;
1651 
1652 	spin_lock(&host->lock);
1653 
1654 	state = host->state;
1655 
1656 	dev_vdbg(&host->pdev->dev,
1657 		"tasklet: state %u pending/completed/mask %lx/%lx/%x\n",
1658 		state, host->pending_events, host->completed_events,
1659 		atmci_readl(host, ATMCI_IMR));
1660 
1661 	do {
1662 		prev_state = state;
1663 		dev_dbg(&host->pdev->dev, "FSM: state=%d\n", state);
1664 
1665 		switch (state) {
1666 		case STATE_IDLE:
1667 			break;
1668 
1669 		case STATE_SENDING_CMD:
1670 			/*
1671 			 * Command has been sent, we are waiting for command
1672 			 * ready. Then we have three next states possible:
1673 			 * END_REQUEST by default, WAITING_NOTBUSY if it's a
1674 			 * command needing it or DATA_XFER if there is data.
1675 			 */
1676 			dev_dbg(&host->pdev->dev, "FSM: cmd ready?\n");
1677 			if (!atmci_test_and_clear_pending(host,
1678 						EVENT_CMD_RDY))
1679 				break;
1680 
1681 			dev_dbg(&host->pdev->dev, "set completed cmd ready\n");
1682 			host->cmd = NULL;
1683 			atmci_set_completed(host, EVENT_CMD_RDY);
1684 			atmci_command_complete(host, mrq->cmd);
1685 			if (mrq->data) {
1686 				dev_dbg(&host->pdev->dev,
1687 				        "command with data transfer");
1688 				/*
1689 				 * If there is a command error don't start
1690 				 * data transfer.
1691 				 */
1692 				if (mrq->cmd->error) {
1693 					host->stop_transfer(host);
1694 					host->data = NULL;
1695 					atmci_writel(host, ATMCI_IDR,
1696 					             ATMCI_TXRDY | ATMCI_RXRDY
1697 					             | ATMCI_DATA_ERROR_FLAGS);
1698 					state = STATE_END_REQUEST;
1699 				} else
1700 					state = STATE_DATA_XFER;
1701 			} else if ((!mrq->data) && (mrq->cmd->flags & MMC_RSP_BUSY)) {
1702 				dev_dbg(&host->pdev->dev,
1703 				        "command response need waiting notbusy");
1704 				atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1705 				state = STATE_WAITING_NOTBUSY;
1706 			} else
1707 				state = STATE_END_REQUEST;
1708 
1709 			break;
1710 
1711 		case STATE_DATA_XFER:
1712 			if (atmci_test_and_clear_pending(host,
1713 						EVENT_DATA_ERROR)) {
1714 				dev_dbg(&host->pdev->dev, "set completed data error\n");
1715 				atmci_set_completed(host, EVENT_DATA_ERROR);
1716 				state = STATE_END_REQUEST;
1717 				break;
1718 			}
1719 
1720 			/*
1721 			 * A data transfer is in progress. The event expected
1722 			 * to move to the next state depends of data transfer
1723 			 * type (PDC or DMA). Once transfer done we can move
1724 			 * to the next step which is WAITING_NOTBUSY in write
1725 			 * case and directly SENDING_STOP in read case.
1726 			 */
1727 			dev_dbg(&host->pdev->dev, "FSM: xfer complete?\n");
1728 			if (!atmci_test_and_clear_pending(host,
1729 						EVENT_XFER_COMPLETE))
1730 				break;
1731 
1732 			dev_dbg(&host->pdev->dev,
1733 			        "(%s) set completed xfer complete\n",
1734 				__func__);
1735 			atmci_set_completed(host, EVENT_XFER_COMPLETE);
1736 
1737 			if (host->caps.need_notbusy_for_read_ops ||
1738 			   (host->data->flags & MMC_DATA_WRITE)) {
1739 				atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1740 				state = STATE_WAITING_NOTBUSY;
1741 			} else if (host->mrq->stop) {
1742 				atmci_writel(host, ATMCI_IER, ATMCI_CMDRDY);
1743 				atmci_send_stop_cmd(host, data);
1744 				state = STATE_SENDING_STOP;
1745 			} else {
1746 				host->data = NULL;
1747 				data->bytes_xfered = data->blocks * data->blksz;
1748 				data->error = 0;
1749 				state = STATE_END_REQUEST;
1750 			}
1751 			break;
1752 
1753 		case STATE_WAITING_NOTBUSY:
1754 			/*
1755 			 * We can be in the state for two reasons: a command
1756 			 * requiring waiting not busy signal (stop command
1757 			 * included) or a write operation. In the latest case,
1758 			 * we need to send a stop command.
1759 			 */
1760 			dev_dbg(&host->pdev->dev, "FSM: not busy?\n");
1761 			if (!atmci_test_and_clear_pending(host,
1762 						EVENT_NOTBUSY))
1763 				break;
1764 
1765 			dev_dbg(&host->pdev->dev, "set completed not busy\n");
1766 			atmci_set_completed(host, EVENT_NOTBUSY);
1767 
1768 			if (host->data) {
1769 				/*
1770 				 * For some commands such as CMD53, even if
1771 				 * there is data transfer, there is no stop
1772 				 * command to send.
1773 				 */
1774 				if (host->mrq->stop) {
1775 					atmci_writel(host, ATMCI_IER,
1776 					             ATMCI_CMDRDY);
1777 					atmci_send_stop_cmd(host, data);
1778 					state = STATE_SENDING_STOP;
1779 				} else {
1780 					host->data = NULL;
1781 					data->bytes_xfered = data->blocks
1782 					                     * data->blksz;
1783 					data->error = 0;
1784 					state = STATE_END_REQUEST;
1785 				}
1786 			} else
1787 				state = STATE_END_REQUEST;
1788 			break;
1789 
1790 		case STATE_SENDING_STOP:
1791 			/*
1792 			 * In this state, it is important to set host->data to
1793 			 * NULL (which is tested in the waiting notbusy state)
1794 			 * in order to go to the end request state instead of
1795 			 * sending stop again.
1796 			 */
1797 			dev_dbg(&host->pdev->dev, "FSM: cmd ready?\n");
1798 			if (!atmci_test_and_clear_pending(host,
1799 						EVENT_CMD_RDY))
1800 				break;
1801 
1802 			dev_dbg(&host->pdev->dev, "FSM: cmd ready\n");
1803 			host->cmd = NULL;
1804 			data->bytes_xfered = data->blocks * data->blksz;
1805 			data->error = 0;
1806 			atmci_command_complete(host, mrq->stop);
1807 			if (mrq->stop->error) {
1808 				host->stop_transfer(host);
1809 				atmci_writel(host, ATMCI_IDR,
1810 				             ATMCI_TXRDY | ATMCI_RXRDY
1811 				             | ATMCI_DATA_ERROR_FLAGS);
1812 				state = STATE_END_REQUEST;
1813 			} else {
1814 				atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1815 				state = STATE_WAITING_NOTBUSY;
1816 			}
1817 			host->data = NULL;
1818 			break;
1819 
1820 		case STATE_END_REQUEST:
1821 			atmci_writel(host, ATMCI_IDR, ATMCI_TXRDY | ATMCI_RXRDY
1822 			                   | ATMCI_DATA_ERROR_FLAGS);
1823 			status = host->data_status;
1824 			if (unlikely(status)) {
1825 				host->stop_transfer(host);
1826 				host->data = NULL;
1827 				if (data) {
1828 					if (status & ATMCI_DTOE) {
1829 						data->error = -ETIMEDOUT;
1830 					} else if (status & ATMCI_DCRCE) {
1831 						data->error = -EILSEQ;
1832 					} else {
1833 						data->error = -EIO;
1834 					}
1835 				}
1836 			}
1837 
1838 			atmci_request_end(host, host->mrq);
1839 			state = STATE_IDLE;
1840 			break;
1841 		}
1842 	} while (state != prev_state);
1843 
1844 	host->state = state;
1845 
1846 	spin_unlock(&host->lock);
1847 }
1848 
1849 static void atmci_read_data_pio(struct atmel_mci *host)
1850 {
1851 	struct scatterlist	*sg = host->sg;
1852 	void			*buf = sg_virt(sg);
1853 	unsigned int		offset = host->pio_offset;
1854 	struct mmc_data		*data = host->data;
1855 	u32			value;
1856 	u32			status;
1857 	unsigned int		nbytes = 0;
1858 
1859 	do {
1860 		value = atmci_readl(host, ATMCI_RDR);
1861 		if (likely(offset + 4 <= sg->length)) {
1862 			put_unaligned(value, (u32 *)(buf + offset));
1863 
1864 			offset += 4;
1865 			nbytes += 4;
1866 
1867 			if (offset == sg->length) {
1868 				flush_dcache_page(sg_page(sg));
1869 				host->sg = sg = sg_next(sg);
1870 				host->sg_len--;
1871 				if (!sg || !host->sg_len)
1872 					goto done;
1873 
1874 				offset = 0;
1875 				buf = sg_virt(sg);
1876 			}
1877 		} else {
1878 			unsigned int remaining = sg->length - offset;
1879 			memcpy(buf + offset, &value, remaining);
1880 			nbytes += remaining;
1881 
1882 			flush_dcache_page(sg_page(sg));
1883 			host->sg = sg = sg_next(sg);
1884 			host->sg_len--;
1885 			if (!sg || !host->sg_len)
1886 				goto done;
1887 
1888 			offset = 4 - remaining;
1889 			buf = sg_virt(sg);
1890 			memcpy(buf, (u8 *)&value + remaining, offset);
1891 			nbytes += offset;
1892 		}
1893 
1894 		status = atmci_readl(host, ATMCI_SR);
1895 		if (status & ATMCI_DATA_ERROR_FLAGS) {
1896 			atmci_writel(host, ATMCI_IDR, (ATMCI_NOTBUSY | ATMCI_RXRDY
1897 						| ATMCI_DATA_ERROR_FLAGS));
1898 			host->data_status = status;
1899 			data->bytes_xfered += nbytes;
1900 			return;
1901 		}
1902 	} while (status & ATMCI_RXRDY);
1903 
1904 	host->pio_offset = offset;
1905 	data->bytes_xfered += nbytes;
1906 
1907 	return;
1908 
1909 done:
1910 	atmci_writel(host, ATMCI_IDR, ATMCI_RXRDY);
1911 	atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1912 	data->bytes_xfered += nbytes;
1913 	smp_wmb();
1914 	atmci_set_pending(host, EVENT_XFER_COMPLETE);
1915 }
1916 
1917 static void atmci_write_data_pio(struct atmel_mci *host)
1918 {
1919 	struct scatterlist	*sg = host->sg;
1920 	void			*buf = sg_virt(sg);
1921 	unsigned int		offset = host->pio_offset;
1922 	struct mmc_data		*data = host->data;
1923 	u32			value;
1924 	u32			status;
1925 	unsigned int		nbytes = 0;
1926 
1927 	do {
1928 		if (likely(offset + 4 <= sg->length)) {
1929 			value = get_unaligned((u32 *)(buf + offset));
1930 			atmci_writel(host, ATMCI_TDR, value);
1931 
1932 			offset += 4;
1933 			nbytes += 4;
1934 			if (offset == sg->length) {
1935 				host->sg = sg = sg_next(sg);
1936 				host->sg_len--;
1937 				if (!sg || !host->sg_len)
1938 					goto done;
1939 
1940 				offset = 0;
1941 				buf = sg_virt(sg);
1942 			}
1943 		} else {
1944 			unsigned int remaining = sg->length - offset;
1945 
1946 			value = 0;
1947 			memcpy(&value, buf + offset, remaining);
1948 			nbytes += remaining;
1949 
1950 			host->sg = sg = sg_next(sg);
1951 			host->sg_len--;
1952 			if (!sg || !host->sg_len) {
1953 				atmci_writel(host, ATMCI_TDR, value);
1954 				goto done;
1955 			}
1956 
1957 			offset = 4 - remaining;
1958 			buf = sg_virt(sg);
1959 			memcpy((u8 *)&value + remaining, buf, offset);
1960 			atmci_writel(host, ATMCI_TDR, value);
1961 			nbytes += offset;
1962 		}
1963 
1964 		status = atmci_readl(host, ATMCI_SR);
1965 		if (status & ATMCI_DATA_ERROR_FLAGS) {
1966 			atmci_writel(host, ATMCI_IDR, (ATMCI_NOTBUSY | ATMCI_TXRDY
1967 						| ATMCI_DATA_ERROR_FLAGS));
1968 			host->data_status = status;
1969 			data->bytes_xfered += nbytes;
1970 			return;
1971 		}
1972 	} while (status & ATMCI_TXRDY);
1973 
1974 	host->pio_offset = offset;
1975 	data->bytes_xfered += nbytes;
1976 
1977 	return;
1978 
1979 done:
1980 	atmci_writel(host, ATMCI_IDR, ATMCI_TXRDY);
1981 	atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1982 	data->bytes_xfered += nbytes;
1983 	smp_wmb();
1984 	atmci_set_pending(host, EVENT_XFER_COMPLETE);
1985 }
1986 
1987 static void atmci_sdio_interrupt(struct atmel_mci *host, u32 status)
1988 {
1989 	int	i;
1990 
1991 	for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
1992 		struct atmel_mci_slot *slot = host->slot[i];
1993 		if (slot && (status & slot->sdio_irq)) {
1994 			mmc_signal_sdio_irq(slot->mmc);
1995 		}
1996 	}
1997 }
1998 
1999 
2000 static irqreturn_t atmci_interrupt(int irq, void *dev_id)
2001 {
2002 	struct atmel_mci	*host = dev_id;
2003 	u32			status, mask, pending;
2004 	unsigned int		pass_count = 0;
2005 
2006 	do {
2007 		status = atmci_readl(host, ATMCI_SR);
2008 		mask = atmci_readl(host, ATMCI_IMR);
2009 		pending = status & mask;
2010 		if (!pending)
2011 			break;
2012 
2013 		if (pending & ATMCI_DATA_ERROR_FLAGS) {
2014 			dev_dbg(&host->pdev->dev, "IRQ: data error\n");
2015 			atmci_writel(host, ATMCI_IDR, ATMCI_DATA_ERROR_FLAGS
2016 					| ATMCI_RXRDY | ATMCI_TXRDY
2017 					| ATMCI_ENDRX | ATMCI_ENDTX
2018 					| ATMCI_RXBUFF | ATMCI_TXBUFE);
2019 
2020 			host->data_status = status;
2021 			dev_dbg(&host->pdev->dev, "set pending data error\n");
2022 			smp_wmb();
2023 			atmci_set_pending(host, EVENT_DATA_ERROR);
2024 			tasklet_schedule(&host->tasklet);
2025 		}
2026 
2027 		if (pending & ATMCI_TXBUFE) {
2028 			dev_dbg(&host->pdev->dev, "IRQ: tx buffer empty\n");
2029 			atmci_writel(host, ATMCI_IDR, ATMCI_TXBUFE);
2030 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDTX);
2031 			/*
2032 			 * We can receive this interruption before having configured
2033 			 * the second pdc buffer, so we need to reconfigure first and
2034 			 * second buffers again
2035 			 */
2036 			if (host->data_size) {
2037 				atmci_pdc_set_both_buf(host, XFER_TRANSMIT);
2038 				atmci_writel(host, ATMCI_IER, ATMCI_ENDTX);
2039 				atmci_writel(host, ATMCI_IER, ATMCI_TXBUFE);
2040 			} else {
2041 				atmci_pdc_complete(host);
2042 			}
2043 		} else if (pending & ATMCI_ENDTX) {
2044 			dev_dbg(&host->pdev->dev, "IRQ: end of tx buffer\n");
2045 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDTX);
2046 
2047 			if (host->data_size) {
2048 				atmci_pdc_set_single_buf(host,
2049 						XFER_TRANSMIT, PDC_SECOND_BUF);
2050 				atmci_writel(host, ATMCI_IER, ATMCI_ENDTX);
2051 			}
2052 		}
2053 
2054 		if (pending & ATMCI_RXBUFF) {
2055 			dev_dbg(&host->pdev->dev, "IRQ: rx buffer full\n");
2056 			atmci_writel(host, ATMCI_IDR, ATMCI_RXBUFF);
2057 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDRX);
2058 			/*
2059 			 * We can receive this interruption before having configured
2060 			 * the second pdc buffer, so we need to reconfigure first and
2061 			 * second buffers again
2062 			 */
2063 			if (host->data_size) {
2064 				atmci_pdc_set_both_buf(host, XFER_RECEIVE);
2065 				atmci_writel(host, ATMCI_IER, ATMCI_ENDRX);
2066 				atmci_writel(host, ATMCI_IER, ATMCI_RXBUFF);
2067 			} else {
2068 				atmci_pdc_complete(host);
2069 			}
2070 		} else if (pending & ATMCI_ENDRX) {
2071 			dev_dbg(&host->pdev->dev, "IRQ: end of rx buffer\n");
2072 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDRX);
2073 
2074 			if (host->data_size) {
2075 				atmci_pdc_set_single_buf(host,
2076 						XFER_RECEIVE, PDC_SECOND_BUF);
2077 				atmci_writel(host, ATMCI_IER, ATMCI_ENDRX);
2078 			}
2079 		}
2080 
2081 		/*
2082 		 * First mci IPs, so mainly the ones having pdc, have some
2083 		 * issues with the notbusy signal. You can't get it after
2084 		 * data transmission if you have not sent a stop command.
2085 		 * The appropriate workaround is to use the BLKE signal.
2086 		 */
2087 		if (pending & ATMCI_BLKE) {
2088 			dev_dbg(&host->pdev->dev, "IRQ: blke\n");
2089 			atmci_writel(host, ATMCI_IDR, ATMCI_BLKE);
2090 			smp_wmb();
2091 			dev_dbg(&host->pdev->dev, "set pending notbusy\n");
2092 			atmci_set_pending(host, EVENT_NOTBUSY);
2093 			tasklet_schedule(&host->tasklet);
2094 		}
2095 
2096 		if (pending & ATMCI_NOTBUSY) {
2097 			dev_dbg(&host->pdev->dev, "IRQ: not_busy\n");
2098 			atmci_writel(host, ATMCI_IDR, ATMCI_NOTBUSY);
2099 			smp_wmb();
2100 			dev_dbg(&host->pdev->dev, "set pending notbusy\n");
2101 			atmci_set_pending(host, EVENT_NOTBUSY);
2102 			tasklet_schedule(&host->tasklet);
2103 		}
2104 
2105 		if (pending & ATMCI_RXRDY)
2106 			atmci_read_data_pio(host);
2107 		if (pending & ATMCI_TXRDY)
2108 			atmci_write_data_pio(host);
2109 
2110 		if (pending & ATMCI_CMDRDY) {
2111 			dev_dbg(&host->pdev->dev, "IRQ: cmd ready\n");
2112 			atmci_writel(host, ATMCI_IDR, ATMCI_CMDRDY);
2113 			host->cmd_status = status;
2114 			smp_wmb();
2115 			dev_dbg(&host->pdev->dev, "set pending cmd rdy\n");
2116 			atmci_set_pending(host, EVENT_CMD_RDY);
2117 			tasklet_schedule(&host->tasklet);
2118 		}
2119 
2120 		if (pending & (ATMCI_SDIOIRQA | ATMCI_SDIOIRQB))
2121 			atmci_sdio_interrupt(host, status);
2122 
2123 	} while (pass_count++ < 5);
2124 
2125 	return pass_count ? IRQ_HANDLED : IRQ_NONE;
2126 }
2127 
2128 static irqreturn_t atmci_detect_interrupt(int irq, void *dev_id)
2129 {
2130 	struct atmel_mci_slot	*slot = dev_id;
2131 
2132 	/*
2133 	 * Disable interrupts until the pin has stabilized and check
2134 	 * the state then. Use mod_timer() since we may be in the
2135 	 * middle of the timer routine when this interrupt triggers.
2136 	 */
2137 	disable_irq_nosync(irq);
2138 	mod_timer(&slot->detect_timer, jiffies + msecs_to_jiffies(20));
2139 
2140 	return IRQ_HANDLED;
2141 }
2142 
2143 static int __init atmci_init_slot(struct atmel_mci *host,
2144 		struct mci_slot_pdata *slot_data, unsigned int id,
2145 		u32 sdc_reg, u32 sdio_irq)
2146 {
2147 	struct mmc_host			*mmc;
2148 	struct atmel_mci_slot		*slot;
2149 
2150 	mmc = mmc_alloc_host(sizeof(struct atmel_mci_slot), &host->pdev->dev);
2151 	if (!mmc)
2152 		return -ENOMEM;
2153 
2154 	slot = mmc_priv(mmc);
2155 	slot->mmc = mmc;
2156 	slot->host = host;
2157 	slot->detect_pin = slot_data->detect_pin;
2158 	slot->wp_pin = slot_data->wp_pin;
2159 	slot->detect_is_active_high = slot_data->detect_is_active_high;
2160 	slot->sdc_reg = sdc_reg;
2161 	slot->sdio_irq = sdio_irq;
2162 
2163 	dev_dbg(&mmc->class_dev,
2164 	        "slot[%u]: bus_width=%u, detect_pin=%d, "
2165 		"detect_is_active_high=%s, wp_pin=%d\n",
2166 		id, slot_data->bus_width, slot_data->detect_pin,
2167 		slot_data->detect_is_active_high ? "true" : "false",
2168 		slot_data->wp_pin);
2169 
2170 	mmc->ops = &atmci_ops;
2171 	mmc->f_min = DIV_ROUND_UP(host->bus_hz, 512);
2172 	mmc->f_max = host->bus_hz / 2;
2173 	mmc->ocr_avail	= MMC_VDD_32_33 | MMC_VDD_33_34;
2174 	if (sdio_irq)
2175 		mmc->caps |= MMC_CAP_SDIO_IRQ;
2176 	if (host->caps.has_highspeed)
2177 		mmc->caps |= MMC_CAP_SD_HIGHSPEED;
2178 	/*
2179 	 * Without the read/write proof capability, it is strongly suggested to
2180 	 * use only one bit for data to prevent fifo underruns and overruns
2181 	 * which will corrupt data.
2182 	 */
2183 	if ((slot_data->bus_width >= 4) && host->caps.has_rwproof)
2184 		mmc->caps |= MMC_CAP_4_BIT_DATA;
2185 
2186 	if (atmci_get_version(host) < 0x200) {
2187 		mmc->max_segs = 256;
2188 		mmc->max_blk_size = 4095;
2189 		mmc->max_blk_count = 256;
2190 		mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
2191 		mmc->max_seg_size = mmc->max_blk_size * mmc->max_segs;
2192 	} else {
2193 		mmc->max_segs = 64;
2194 		mmc->max_req_size = 32768 * 512;
2195 		mmc->max_blk_size = 32768;
2196 		mmc->max_blk_count = 512;
2197 	}
2198 
2199 	/* Assume card is present initially */
2200 	set_bit(ATMCI_CARD_PRESENT, &slot->flags);
2201 	if (gpio_is_valid(slot->detect_pin)) {
2202 		if (devm_gpio_request(&host->pdev->dev, slot->detect_pin,
2203 				      "mmc_detect")) {
2204 			dev_dbg(&mmc->class_dev, "no detect pin available\n");
2205 			slot->detect_pin = -EBUSY;
2206 		} else if (gpio_get_value(slot->detect_pin) ^
2207 				slot->detect_is_active_high) {
2208 			clear_bit(ATMCI_CARD_PRESENT, &slot->flags);
2209 		}
2210 	}
2211 
2212 	if (!gpio_is_valid(slot->detect_pin)) {
2213 		if (slot_data->non_removable)
2214 			mmc->caps |= MMC_CAP_NONREMOVABLE;
2215 		else
2216 			mmc->caps |= MMC_CAP_NEEDS_POLL;
2217 	}
2218 
2219 	if (gpio_is_valid(slot->wp_pin)) {
2220 		if (devm_gpio_request(&host->pdev->dev, slot->wp_pin,
2221 				      "mmc_wp")) {
2222 			dev_dbg(&mmc->class_dev, "no WP pin available\n");
2223 			slot->wp_pin = -EBUSY;
2224 		}
2225 	}
2226 
2227 	host->slot[id] = slot;
2228 	mmc_regulator_get_supply(mmc);
2229 	mmc_add_host(mmc);
2230 
2231 	if (gpio_is_valid(slot->detect_pin)) {
2232 		int ret;
2233 
2234 		setup_timer(&slot->detect_timer, atmci_detect_change,
2235 				(unsigned long)slot);
2236 
2237 		ret = request_irq(gpio_to_irq(slot->detect_pin),
2238 				atmci_detect_interrupt,
2239 				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
2240 				"mmc-detect", slot);
2241 		if (ret) {
2242 			dev_dbg(&mmc->class_dev,
2243 				"could not request IRQ %d for detect pin\n",
2244 				gpio_to_irq(slot->detect_pin));
2245 			slot->detect_pin = -EBUSY;
2246 		}
2247 	}
2248 
2249 	atmci_init_debugfs(slot);
2250 
2251 	return 0;
2252 }
2253 
2254 static void atmci_cleanup_slot(struct atmel_mci_slot *slot,
2255 		unsigned int id)
2256 {
2257 	/* Debugfs stuff is cleaned up by mmc core */
2258 
2259 	set_bit(ATMCI_SHUTDOWN, &slot->flags);
2260 	smp_wmb();
2261 
2262 	mmc_remove_host(slot->mmc);
2263 
2264 	if (gpio_is_valid(slot->detect_pin)) {
2265 		int pin = slot->detect_pin;
2266 
2267 		free_irq(gpio_to_irq(pin), slot);
2268 		del_timer_sync(&slot->detect_timer);
2269 	}
2270 
2271 	slot->host->slot[id] = NULL;
2272 	mmc_free_host(slot->mmc);
2273 }
2274 
2275 static bool atmci_filter(struct dma_chan *chan, void *pdata)
2276 {
2277 	struct mci_platform_data *sl_pdata = pdata;
2278 	struct mci_dma_data *sl;
2279 
2280 	if (!sl_pdata)
2281 		return false;
2282 
2283 	sl = sl_pdata->dma_slave;
2284 	if (sl && find_slave_dev(sl) == chan->device->dev) {
2285 		chan->private = slave_data_ptr(sl);
2286 		return true;
2287 	} else {
2288 		return false;
2289 	}
2290 }
2291 
2292 static bool atmci_configure_dma(struct atmel_mci *host)
2293 {
2294 	struct mci_platform_data	*pdata;
2295 	dma_cap_mask_t mask;
2296 
2297 	if (host == NULL)
2298 		return false;
2299 
2300 	pdata = host->pdev->dev.platform_data;
2301 
2302 	dma_cap_zero(mask);
2303 	dma_cap_set(DMA_SLAVE, mask);
2304 
2305 	host->dma.chan = dma_request_slave_channel_compat(mask, atmci_filter, pdata,
2306 							  &host->pdev->dev, "rxtx");
2307 	if (!host->dma.chan) {
2308 		dev_warn(&host->pdev->dev, "no DMA channel available\n");
2309 		return false;
2310 	} else {
2311 		dev_info(&host->pdev->dev,
2312 					"using %s for DMA transfers\n",
2313 					dma_chan_name(host->dma.chan));
2314 
2315 		host->dma_conf.src_addr = host->mapbase + ATMCI_RDR;
2316 		host->dma_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
2317 		host->dma_conf.src_maxburst = 1;
2318 		host->dma_conf.dst_addr = host->mapbase + ATMCI_TDR;
2319 		host->dma_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
2320 		host->dma_conf.dst_maxburst = 1;
2321 		host->dma_conf.device_fc = false;
2322 		return true;
2323 	}
2324 }
2325 
2326 /*
2327  * HSMCI (High Speed MCI) module is not fully compatible with MCI module.
2328  * HSMCI provides DMA support and a new config register but no more supports
2329  * PDC.
2330  */
2331 static void __init atmci_get_cap(struct atmel_mci *host)
2332 {
2333 	unsigned int version;
2334 
2335 	version = atmci_get_version(host);
2336 	dev_info(&host->pdev->dev,
2337 			"version: 0x%x\n", version);
2338 
2339 	host->caps.has_dma_conf_reg = 0;
2340 	host->caps.has_pdc = ATMCI_PDC_CONNECTED;
2341 	host->caps.has_cfg_reg = 0;
2342 	host->caps.has_cstor_reg = 0;
2343 	host->caps.has_highspeed = 0;
2344 	host->caps.has_rwproof = 0;
2345 	host->caps.has_odd_clk_div = 0;
2346 	host->caps.has_bad_data_ordering = 1;
2347 	host->caps.need_reset_after_xfer = 1;
2348 	host->caps.need_blksz_mul_4 = 1;
2349 	host->caps.need_notbusy_for_read_ops = 0;
2350 
2351 	/* keep only major version number */
2352 	switch (version & 0xf00) {
2353 	case 0x600:
2354 	case 0x500:
2355 		host->caps.has_odd_clk_div = 1;
2356 	case 0x400:
2357 	case 0x300:
2358 		host->caps.has_dma_conf_reg = 1;
2359 		host->caps.has_pdc = 0;
2360 		host->caps.has_cfg_reg = 1;
2361 		host->caps.has_cstor_reg = 1;
2362 		host->caps.has_highspeed = 1;
2363 	case 0x200:
2364 		host->caps.has_rwproof = 1;
2365 		host->caps.need_blksz_mul_4 = 0;
2366 		host->caps.need_notbusy_for_read_ops = 1;
2367 	case 0x100:
2368 		host->caps.has_bad_data_ordering = 0;
2369 		host->caps.need_reset_after_xfer = 0;
2370 	case 0x0:
2371 		break;
2372 	default:
2373 		host->caps.has_pdc = 0;
2374 		dev_warn(&host->pdev->dev,
2375 				"Unmanaged mci version, set minimum capabilities\n");
2376 		break;
2377 	}
2378 }
2379 
2380 static int __init atmci_probe(struct platform_device *pdev)
2381 {
2382 	struct mci_platform_data	*pdata;
2383 	struct atmel_mci		*host;
2384 	struct resource			*regs;
2385 	unsigned int			nr_slots;
2386 	int				irq;
2387 	int				ret, i;
2388 
2389 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2390 	if (!regs)
2391 		return -ENXIO;
2392 	pdata = pdev->dev.platform_data;
2393 	if (!pdata) {
2394 		pdata = atmci_of_init(pdev);
2395 		if (IS_ERR(pdata)) {
2396 			dev_err(&pdev->dev, "platform data not available\n");
2397 			return PTR_ERR(pdata);
2398 		}
2399 	}
2400 
2401 	irq = platform_get_irq(pdev, 0);
2402 	if (irq < 0)
2403 		return irq;
2404 
2405 	host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
2406 	if (!host)
2407 		return -ENOMEM;
2408 
2409 	host->pdev = pdev;
2410 	spin_lock_init(&host->lock);
2411 	INIT_LIST_HEAD(&host->queue);
2412 
2413 	host->mck = devm_clk_get(&pdev->dev, "mci_clk");
2414 	if (IS_ERR(host->mck))
2415 		return PTR_ERR(host->mck);
2416 
2417 	host->regs = devm_ioremap(&pdev->dev, regs->start, resource_size(regs));
2418 	if (!host->regs)
2419 		return -ENOMEM;
2420 
2421 	ret = clk_prepare_enable(host->mck);
2422 	if (ret)
2423 		return ret;
2424 
2425 	atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
2426 	host->bus_hz = clk_get_rate(host->mck);
2427 	clk_disable_unprepare(host->mck);
2428 
2429 	host->mapbase = regs->start;
2430 
2431 	tasklet_init(&host->tasklet, atmci_tasklet_func, (unsigned long)host);
2432 
2433 	ret = request_irq(irq, atmci_interrupt, 0, dev_name(&pdev->dev), host);
2434 	if (ret)
2435 		return ret;
2436 
2437 	/* Get MCI capabilities and set operations according to it */
2438 	atmci_get_cap(host);
2439 	if (atmci_configure_dma(host)) {
2440 		host->prepare_data = &atmci_prepare_data_dma;
2441 		host->submit_data = &atmci_submit_data_dma;
2442 		host->stop_transfer = &atmci_stop_transfer_dma;
2443 	} else if (host->caps.has_pdc) {
2444 		dev_info(&pdev->dev, "using PDC\n");
2445 		host->prepare_data = &atmci_prepare_data_pdc;
2446 		host->submit_data = &atmci_submit_data_pdc;
2447 		host->stop_transfer = &atmci_stop_transfer_pdc;
2448 	} else {
2449 		dev_info(&pdev->dev, "using PIO\n");
2450 		host->prepare_data = &atmci_prepare_data;
2451 		host->submit_data = &atmci_submit_data;
2452 		host->stop_transfer = &atmci_stop_transfer;
2453 	}
2454 
2455 	platform_set_drvdata(pdev, host);
2456 
2457 	setup_timer(&host->timer, atmci_timeout_timer, (unsigned long)host);
2458 
2459 	/* We need at least one slot to succeed */
2460 	nr_slots = 0;
2461 	ret = -ENODEV;
2462 	if (pdata->slot[0].bus_width) {
2463 		ret = atmci_init_slot(host, &pdata->slot[0],
2464 				0, ATMCI_SDCSEL_SLOT_A, ATMCI_SDIOIRQA);
2465 		if (!ret) {
2466 			nr_slots++;
2467 			host->buf_size = host->slot[0]->mmc->max_req_size;
2468 		}
2469 	}
2470 	if (pdata->slot[1].bus_width) {
2471 		ret = atmci_init_slot(host, &pdata->slot[1],
2472 				1, ATMCI_SDCSEL_SLOT_B, ATMCI_SDIOIRQB);
2473 		if (!ret) {
2474 			nr_slots++;
2475 			if (host->slot[1]->mmc->max_req_size > host->buf_size)
2476 				host->buf_size =
2477 					host->slot[1]->mmc->max_req_size;
2478 		}
2479 	}
2480 
2481 	if (!nr_slots) {
2482 		dev_err(&pdev->dev, "init failed: no slot defined\n");
2483 		goto err_init_slot;
2484 	}
2485 
2486 	if (!host->caps.has_rwproof) {
2487 		host->buffer = dma_alloc_coherent(&pdev->dev, host->buf_size,
2488 		                                  &host->buf_phys_addr,
2489 						  GFP_KERNEL);
2490 		if (!host->buffer) {
2491 			ret = -ENOMEM;
2492 			dev_err(&pdev->dev, "buffer allocation failed\n");
2493 			goto err_dma_alloc;
2494 		}
2495 	}
2496 
2497 	dev_info(&pdev->dev,
2498 			"Atmel MCI controller at 0x%08lx irq %d, %u slots\n",
2499 			host->mapbase, irq, nr_slots);
2500 
2501 	return 0;
2502 
2503 err_dma_alloc:
2504 	for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
2505 		if (host->slot[i])
2506 			atmci_cleanup_slot(host->slot[i], i);
2507 	}
2508 err_init_slot:
2509 	del_timer_sync(&host->timer);
2510 	if (host->dma.chan)
2511 		dma_release_channel(host->dma.chan);
2512 	free_irq(irq, host);
2513 	return ret;
2514 }
2515 
2516 static int __exit atmci_remove(struct platform_device *pdev)
2517 {
2518 	struct atmel_mci	*host = platform_get_drvdata(pdev);
2519 	unsigned int		i;
2520 
2521 	if (host->buffer)
2522 		dma_free_coherent(&pdev->dev, host->buf_size,
2523 		                  host->buffer, host->buf_phys_addr);
2524 
2525 	for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
2526 		if (host->slot[i])
2527 			atmci_cleanup_slot(host->slot[i], i);
2528 	}
2529 
2530 	clk_prepare_enable(host->mck);
2531 	atmci_writel(host, ATMCI_IDR, ~0UL);
2532 	atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIDIS);
2533 	atmci_readl(host, ATMCI_SR);
2534 	clk_disable_unprepare(host->mck);
2535 
2536 	del_timer_sync(&host->timer);
2537 	if (host->dma.chan)
2538 		dma_release_channel(host->dma.chan);
2539 
2540 	free_irq(platform_get_irq(pdev, 0), host);
2541 
2542 	return 0;
2543 }
2544 
2545 static struct platform_driver atmci_driver = {
2546 	.remove		= __exit_p(atmci_remove),
2547 	.driver		= {
2548 		.name		= "atmel_mci",
2549 		.of_match_table	= of_match_ptr(atmci_dt_ids),
2550 	},
2551 };
2552 
2553 static int __init atmci_init(void)
2554 {
2555 	return platform_driver_probe(&atmci_driver, atmci_probe);
2556 }
2557 
2558 static void __exit atmci_exit(void)
2559 {
2560 	platform_driver_unregister(&atmci_driver);
2561 }
2562 
2563 late_initcall(atmci_init); /* try to load after dma driver when built-in */
2564 module_exit(atmci_exit);
2565 
2566 MODULE_DESCRIPTION("Atmel Multimedia Card Interface driver");
2567 MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
2568 MODULE_LICENSE("GPL v2");
2569