xref: /openbmc/linux/drivers/mmc/host/atmel-mci.c (revision 62e7ca52)
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/ioport.h>
21 #include <linux/module.h>
22 #include <linux/of.h>
23 #include <linux/of_device.h>
24 #include <linux/of_gpio.h>
25 #include <linux/platform_device.h>
26 #include <linux/scatterlist.h>
27 #include <linux/seq_file.h>
28 #include <linux/slab.h>
29 #include <linux/stat.h>
30 #include <linux/types.h>
31 #include <linux/platform_data/atmel.h>
32 
33 #include <linux/mmc/host.h>
34 #include <linux/mmc/sdio.h>
35 
36 #include <mach/atmel-mci.h>
37 #include <linux/atmel-mci.h>
38 #include <linux/atmel_pdc.h>
39 
40 #include <asm/cacheflush.h>
41 #include <asm/io.h>
42 #include <asm/unaligned.h>
43 
44 #include "atmel-mci-regs.h"
45 
46 #define ATMCI_DATA_ERROR_FLAGS	(ATMCI_DCRCE | ATMCI_DTOE | ATMCI_OVRE | ATMCI_UNRE)
47 #define ATMCI_DMA_THRESHOLD	16
48 
49 enum {
50 	EVENT_CMD_RDY = 0,
51 	EVENT_XFER_COMPLETE,
52 	EVENT_NOTBUSY,
53 	EVENT_DATA_ERROR,
54 };
55 
56 enum atmel_mci_state {
57 	STATE_IDLE = 0,
58 	STATE_SENDING_CMD,
59 	STATE_DATA_XFER,
60 	STATE_WAITING_NOTBUSY,
61 	STATE_SENDING_STOP,
62 	STATE_END_REQUEST,
63 };
64 
65 enum atmci_xfer_dir {
66 	XFER_RECEIVE = 0,
67 	XFER_TRANSMIT,
68 };
69 
70 enum atmci_pdc_buf {
71 	PDC_FIRST_BUF = 0,
72 	PDC_SECOND_BUF,
73 };
74 
75 struct atmel_mci_caps {
76 	bool    has_dma_conf_reg;
77 	bool    has_pdc;
78 	bool    has_cfg_reg;
79 	bool    has_cstor_reg;
80 	bool    has_highspeed;
81 	bool    has_rwproof;
82 	bool	has_odd_clk_div;
83 	bool	has_bad_data_ordering;
84 	bool	need_reset_after_xfer;
85 	bool	need_blksz_mul_4;
86 	bool	need_notbusy_for_read_ops;
87 };
88 
89 struct atmel_mci_dma {
90 	struct dma_chan			*chan;
91 	struct dma_async_tx_descriptor	*data_desc;
92 };
93 
94 /**
95  * struct atmel_mci - MMC controller state shared between all slots
96  * @lock: Spinlock protecting the queue and associated data.
97  * @regs: Pointer to MMIO registers.
98  * @sg: Scatterlist entry currently being processed by PIO or PDC code.
99  * @pio_offset: Offset into the current scatterlist entry.
100  * @buffer: Buffer used if we don't have the r/w proof capability. We
101  *      don't have the time to switch pdc buffers so we have to use only
102  *      one buffer for the full transaction.
103  * @buf_size: size of the buffer.
104  * @phys_buf_addr: buffer address needed for pdc.
105  * @cur_slot: The slot which is currently using the controller.
106  * @mrq: The request currently being processed on @cur_slot,
107  *	or NULL if the controller is idle.
108  * @cmd: The command currently being sent to the card, or NULL.
109  * @data: The data currently being transferred, or NULL if no data
110  *	transfer is in progress.
111  * @data_size: just data->blocks * data->blksz.
112  * @dma: DMA client state.
113  * @data_chan: DMA channel being used for the current data transfer.
114  * @cmd_status: Snapshot of SR taken upon completion of the current
115  *	command. Only valid when EVENT_CMD_COMPLETE is pending.
116  * @data_status: Snapshot of SR taken upon completion of the current
117  *	data transfer. Only valid when EVENT_DATA_COMPLETE or
118  *	EVENT_DATA_ERROR is pending.
119  * @stop_cmdr: Value to be loaded into CMDR when the stop command is
120  *	to be sent.
121  * @tasklet: Tasklet running the request state machine.
122  * @pending_events: Bitmask of events flagged by the interrupt handler
123  *	to be processed by the tasklet.
124  * @completed_events: Bitmask of events which the state machine has
125  *	processed.
126  * @state: Tasklet state.
127  * @queue: List of slots waiting for access to the controller.
128  * @need_clock_update: Update the clock rate before the next request.
129  * @need_reset: Reset controller before next request.
130  * @timer: Timer to balance the data timeout error flag which cannot rise.
131  * @mode_reg: Value of the MR register.
132  * @cfg_reg: Value of the CFG register.
133  * @bus_hz: The rate of @mck in Hz. This forms the basis for MMC bus
134  *	rate and timeout calculations.
135  * @mapbase: Physical address of the MMIO registers.
136  * @mck: The peripheral bus clock hooked up to the MMC controller.
137  * @pdev: Platform device associated with the MMC controller.
138  * @slot: Slots sharing this MMC controller.
139  * @caps: MCI capabilities depending on MCI version.
140  * @prepare_data: function to setup MCI before data transfer which
141  * depends on MCI capabilities.
142  * @submit_data: function to start data transfer which depends on MCI
143  * capabilities.
144  * @stop_transfer: function to stop data transfer which depends on MCI
145  * capabilities.
146  *
147  * Locking
148  * =======
149  *
150  * @lock is a softirq-safe spinlock protecting @queue as well as
151  * @cur_slot, @mrq and @state. These must always be updated
152  * at the same time while holding @lock.
153  *
154  * @lock also protects mode_reg and need_clock_update since these are
155  * used to synchronize mode register updates with the queue
156  * processing.
157  *
158  * The @mrq field of struct atmel_mci_slot is also protected by @lock,
159  * and must always be written at the same time as the slot is added to
160  * @queue.
161  *
162  * @pending_events and @completed_events are accessed using atomic bit
163  * operations, so they don't need any locking.
164  *
165  * None of the fields touched by the interrupt handler need any
166  * locking. However, ordering is important: Before EVENT_DATA_ERROR or
167  * EVENT_DATA_COMPLETE is set in @pending_events, all data-related
168  * interrupts must be disabled and @data_status updated with a
169  * snapshot of SR. Similarly, before EVENT_CMD_COMPLETE is set, the
170  * CMDRDY interrupt must be disabled and @cmd_status updated with a
171  * snapshot of SR, and before EVENT_XFER_COMPLETE can be set, the
172  * bytes_xfered field of @data must be written. This is ensured by
173  * using barriers.
174  */
175 struct atmel_mci {
176 	spinlock_t		lock;
177 	void __iomem		*regs;
178 
179 	struct scatterlist	*sg;
180 	unsigned int		sg_len;
181 	unsigned int		pio_offset;
182 	unsigned int		*buffer;
183 	unsigned int		buf_size;
184 	dma_addr_t		buf_phys_addr;
185 
186 	struct atmel_mci_slot	*cur_slot;
187 	struct mmc_request	*mrq;
188 	struct mmc_command	*cmd;
189 	struct mmc_data		*data;
190 	unsigned int		data_size;
191 
192 	struct atmel_mci_dma	dma;
193 	struct dma_chan		*data_chan;
194 	struct dma_slave_config	dma_conf;
195 
196 	u32			cmd_status;
197 	u32			data_status;
198 	u32			stop_cmdr;
199 
200 	struct tasklet_struct	tasklet;
201 	unsigned long		pending_events;
202 	unsigned long		completed_events;
203 	enum atmel_mci_state	state;
204 	struct list_head	queue;
205 
206 	bool			need_clock_update;
207 	bool			need_reset;
208 	struct timer_list	timer;
209 	u32			mode_reg;
210 	u32			cfg_reg;
211 	unsigned long		bus_hz;
212 	unsigned long		mapbase;
213 	struct clk		*mck;
214 	struct platform_device	*pdev;
215 
216 	struct atmel_mci_slot	*slot[ATMCI_MAX_NR_SLOTS];
217 
218 	struct atmel_mci_caps   caps;
219 
220 	u32 (*prepare_data)(struct atmel_mci *host, struct mmc_data *data);
221 	void (*submit_data)(struct atmel_mci *host, struct mmc_data *data);
222 	void (*stop_transfer)(struct atmel_mci *host);
223 };
224 
225 /**
226  * struct atmel_mci_slot - MMC slot state
227  * @mmc: The mmc_host representing this slot.
228  * @host: The MMC controller this slot is using.
229  * @sdc_reg: Value of SDCR to be written before using this slot.
230  * @sdio_irq: SDIO irq mask for this slot.
231  * @mrq: mmc_request currently being processed or waiting to be
232  *	processed, or NULL when the slot is idle.
233  * @queue_node: List node for placing this node in the @queue list of
234  *	&struct atmel_mci.
235  * @clock: Clock rate configured by set_ios(). Protected by host->lock.
236  * @flags: Random state bits associated with the slot.
237  * @detect_pin: GPIO pin used for card detection, or negative if not
238  *	available.
239  * @wp_pin: GPIO pin used for card write protect sending, or negative
240  *	if not available.
241  * @detect_is_active_high: The state of the detect pin when it is active.
242  * @detect_timer: Timer used for debouncing @detect_pin interrupts.
243  */
244 struct atmel_mci_slot {
245 	struct mmc_host		*mmc;
246 	struct atmel_mci	*host;
247 
248 	u32			sdc_reg;
249 	u32			sdio_irq;
250 
251 	struct mmc_request	*mrq;
252 	struct list_head	queue_node;
253 
254 	unsigned int		clock;
255 	unsigned long		flags;
256 #define ATMCI_CARD_PRESENT	0
257 #define ATMCI_CARD_NEED_INIT	1
258 #define ATMCI_SHUTDOWN		2
259 
260 	int			detect_pin;
261 	int			wp_pin;
262 	bool			detect_is_active_high;
263 
264 	struct timer_list	detect_timer;
265 };
266 
267 #define atmci_test_and_clear_pending(host, event)		\
268 	test_and_clear_bit(event, &host->pending_events)
269 #define atmci_set_completed(host, event)			\
270 	set_bit(event, &host->completed_events)
271 #define atmci_set_pending(host, event)				\
272 	set_bit(event, &host->pending_events)
273 
274 /*
275  * The debugfs stuff below is mostly optimized away when
276  * CONFIG_DEBUG_FS is not set.
277  */
278 static int atmci_req_show(struct seq_file *s, void *v)
279 {
280 	struct atmel_mci_slot	*slot = s->private;
281 	struct mmc_request	*mrq;
282 	struct mmc_command	*cmd;
283 	struct mmc_command	*stop;
284 	struct mmc_data		*data;
285 
286 	/* Make sure we get a consistent snapshot */
287 	spin_lock_bh(&slot->host->lock);
288 	mrq = slot->mrq;
289 
290 	if (mrq) {
291 		cmd = mrq->cmd;
292 		data = mrq->data;
293 		stop = mrq->stop;
294 
295 		if (cmd)
296 			seq_printf(s,
297 				"CMD%u(0x%x) flg %x rsp %x %x %x %x err %d\n",
298 				cmd->opcode, cmd->arg, cmd->flags,
299 				cmd->resp[0], cmd->resp[1], cmd->resp[2],
300 				cmd->resp[3], cmd->error);
301 		if (data)
302 			seq_printf(s, "DATA %u / %u * %u flg %x err %d\n",
303 				data->bytes_xfered, data->blocks,
304 				data->blksz, data->flags, data->error);
305 		if (stop)
306 			seq_printf(s,
307 				"CMD%u(0x%x) flg %x rsp %x %x %x %x err %d\n",
308 				stop->opcode, stop->arg, stop->flags,
309 				stop->resp[0], stop->resp[1], stop->resp[2],
310 				stop->resp[3], stop->error);
311 	}
312 
313 	spin_unlock_bh(&slot->host->lock);
314 
315 	return 0;
316 }
317 
318 static int atmci_req_open(struct inode *inode, struct file *file)
319 {
320 	return single_open(file, atmci_req_show, inode->i_private);
321 }
322 
323 static const struct file_operations atmci_req_fops = {
324 	.owner		= THIS_MODULE,
325 	.open		= atmci_req_open,
326 	.read		= seq_read,
327 	.llseek		= seq_lseek,
328 	.release	= single_release,
329 };
330 
331 static void atmci_show_status_reg(struct seq_file *s,
332 		const char *regname, u32 value)
333 {
334 	static const char	*sr_bit[] = {
335 		[0]	= "CMDRDY",
336 		[1]	= "RXRDY",
337 		[2]	= "TXRDY",
338 		[3]	= "BLKE",
339 		[4]	= "DTIP",
340 		[5]	= "NOTBUSY",
341 		[6]	= "ENDRX",
342 		[7]	= "ENDTX",
343 		[8]	= "SDIOIRQA",
344 		[9]	= "SDIOIRQB",
345 		[12]	= "SDIOWAIT",
346 		[14]	= "RXBUFF",
347 		[15]	= "TXBUFE",
348 		[16]	= "RINDE",
349 		[17]	= "RDIRE",
350 		[18]	= "RCRCE",
351 		[19]	= "RENDE",
352 		[20]	= "RTOE",
353 		[21]	= "DCRCE",
354 		[22]	= "DTOE",
355 		[23]	= "CSTOE",
356 		[24]	= "BLKOVRE",
357 		[25]	= "DMADONE",
358 		[26]	= "FIFOEMPTY",
359 		[27]	= "XFRDONE",
360 		[30]	= "OVRE",
361 		[31]	= "UNRE",
362 	};
363 	unsigned int		i;
364 
365 	seq_printf(s, "%s:\t0x%08x", regname, value);
366 	for (i = 0; i < ARRAY_SIZE(sr_bit); i++) {
367 		if (value & (1 << i)) {
368 			if (sr_bit[i])
369 				seq_printf(s, " %s", sr_bit[i]);
370 			else
371 				seq_puts(s, " UNKNOWN");
372 		}
373 	}
374 	seq_putc(s, '\n');
375 }
376 
377 static int atmci_regs_show(struct seq_file *s, void *v)
378 {
379 	struct atmel_mci	*host = s->private;
380 	u32			*buf;
381 	int			ret = 0;
382 
383 
384 	buf = kmalloc(ATMCI_REGS_SIZE, GFP_KERNEL);
385 	if (!buf)
386 		return -ENOMEM;
387 
388 	/*
389 	 * Grab a more or less consistent snapshot. Note that we're
390 	 * not disabling interrupts, so IMR and SR may not be
391 	 * consistent.
392 	 */
393 	ret = clk_prepare_enable(host->mck);
394 	if (ret)
395 		goto out;
396 
397 	spin_lock_bh(&host->lock);
398 	memcpy_fromio(buf, host->regs, ATMCI_REGS_SIZE);
399 	spin_unlock_bh(&host->lock);
400 
401 	clk_disable_unprepare(host->mck);
402 
403 	seq_printf(s, "MR:\t0x%08x%s%s ",
404 			buf[ATMCI_MR / 4],
405 			buf[ATMCI_MR / 4] & ATMCI_MR_RDPROOF ? " RDPROOF" : "",
406 			buf[ATMCI_MR / 4] & ATMCI_MR_WRPROOF ? " WRPROOF" : "");
407 	if (host->caps.has_odd_clk_div)
408 		seq_printf(s, "{CLKDIV,CLKODD}=%u\n",
409 				((buf[ATMCI_MR / 4] & 0xff) << 1)
410 				| ((buf[ATMCI_MR / 4] >> 16) & 1));
411 	else
412 		seq_printf(s, "CLKDIV=%u\n",
413 				(buf[ATMCI_MR / 4] & 0xff));
414 	seq_printf(s, "DTOR:\t0x%08x\n", buf[ATMCI_DTOR / 4]);
415 	seq_printf(s, "SDCR:\t0x%08x\n", buf[ATMCI_SDCR / 4]);
416 	seq_printf(s, "ARGR:\t0x%08x\n", buf[ATMCI_ARGR / 4]);
417 	seq_printf(s, "BLKR:\t0x%08x BCNT=%u BLKLEN=%u\n",
418 			buf[ATMCI_BLKR / 4],
419 			buf[ATMCI_BLKR / 4] & 0xffff,
420 			(buf[ATMCI_BLKR / 4] >> 16) & 0xffff);
421 	if (host->caps.has_cstor_reg)
422 		seq_printf(s, "CSTOR:\t0x%08x\n", buf[ATMCI_CSTOR / 4]);
423 
424 	/* Don't read RSPR and RDR; it will consume the data there */
425 
426 	atmci_show_status_reg(s, "SR", buf[ATMCI_SR / 4]);
427 	atmci_show_status_reg(s, "IMR", buf[ATMCI_IMR / 4]);
428 
429 	if (host->caps.has_dma_conf_reg) {
430 		u32 val;
431 
432 		val = buf[ATMCI_DMA / 4];
433 		seq_printf(s, "DMA:\t0x%08x OFFSET=%u CHKSIZE=%u%s\n",
434 				val, val & 3,
435 				((val >> 4) & 3) ?
436 					1 << (((val >> 4) & 3) + 1) : 1,
437 				val & ATMCI_DMAEN ? " DMAEN" : "");
438 	}
439 	if (host->caps.has_cfg_reg) {
440 		u32 val;
441 
442 		val = buf[ATMCI_CFG / 4];
443 		seq_printf(s, "CFG:\t0x%08x%s%s%s%s\n",
444 				val,
445 				val & ATMCI_CFG_FIFOMODE_1DATA ? " FIFOMODE_ONE_DATA" : "",
446 				val & ATMCI_CFG_FERRCTRL_COR ? " FERRCTRL_CLEAR_ON_READ" : "",
447 				val & ATMCI_CFG_HSMODE ? " HSMODE" : "",
448 				val & ATMCI_CFG_LSYNC ? " LSYNC" : "");
449 	}
450 
451 out:
452 	kfree(buf);
453 
454 	return ret;
455 }
456 
457 static int atmci_regs_open(struct inode *inode, struct file *file)
458 {
459 	return single_open(file, atmci_regs_show, inode->i_private);
460 }
461 
462 static const struct file_operations atmci_regs_fops = {
463 	.owner		= THIS_MODULE,
464 	.open		= atmci_regs_open,
465 	.read		= seq_read,
466 	.llseek		= seq_lseek,
467 	.release	= single_release,
468 };
469 
470 static void atmci_init_debugfs(struct atmel_mci_slot *slot)
471 {
472 	struct mmc_host		*mmc = slot->mmc;
473 	struct atmel_mci	*host = slot->host;
474 	struct dentry		*root;
475 	struct dentry		*node;
476 
477 	root = mmc->debugfs_root;
478 	if (!root)
479 		return;
480 
481 	node = debugfs_create_file("regs", S_IRUSR, root, host,
482 			&atmci_regs_fops);
483 	if (IS_ERR(node))
484 		return;
485 	if (!node)
486 		goto err;
487 
488 	node = debugfs_create_file("req", S_IRUSR, root, slot, &atmci_req_fops);
489 	if (!node)
490 		goto err;
491 
492 	node = debugfs_create_u32("state", S_IRUSR, root, (u32 *)&host->state);
493 	if (!node)
494 		goto err;
495 
496 	node = debugfs_create_x32("pending_events", S_IRUSR, root,
497 				     (u32 *)&host->pending_events);
498 	if (!node)
499 		goto err;
500 
501 	node = debugfs_create_x32("completed_events", S_IRUSR, root,
502 				     (u32 *)&host->completed_events);
503 	if (!node)
504 		goto err;
505 
506 	return;
507 
508 err:
509 	dev_err(&mmc->class_dev, "failed to initialize debugfs for slot\n");
510 }
511 
512 #if defined(CONFIG_OF)
513 static const struct of_device_id atmci_dt_ids[] = {
514 	{ .compatible = "atmel,hsmci" },
515 	{ /* sentinel */ }
516 };
517 
518 MODULE_DEVICE_TABLE(of, atmci_dt_ids);
519 
520 static struct mci_platform_data*
521 atmci_of_init(struct platform_device *pdev)
522 {
523 	struct device_node *np = pdev->dev.of_node;
524 	struct device_node *cnp;
525 	struct mci_platform_data *pdata;
526 	u32 slot_id;
527 
528 	if (!np) {
529 		dev_err(&pdev->dev, "device node not found\n");
530 		return ERR_PTR(-EINVAL);
531 	}
532 
533 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
534 	if (!pdata) {
535 		dev_err(&pdev->dev, "could not allocate memory for pdata\n");
536 		return ERR_PTR(-ENOMEM);
537 	}
538 
539 	for_each_child_of_node(np, cnp) {
540 		if (of_property_read_u32(cnp, "reg", &slot_id)) {
541 			dev_warn(&pdev->dev, "reg property is missing for %s\n",
542 				 cnp->full_name);
543 			continue;
544 		}
545 
546 		if (slot_id >= ATMCI_MAX_NR_SLOTS) {
547 			dev_warn(&pdev->dev, "can't have more than %d slots\n",
548 			         ATMCI_MAX_NR_SLOTS);
549 			break;
550 		}
551 
552 		if (of_property_read_u32(cnp, "bus-width",
553 		                         &pdata->slot[slot_id].bus_width))
554 			pdata->slot[slot_id].bus_width = 1;
555 
556 		pdata->slot[slot_id].detect_pin =
557 			of_get_named_gpio(cnp, "cd-gpios", 0);
558 
559 		pdata->slot[slot_id].detect_is_active_high =
560 			of_property_read_bool(cnp, "cd-inverted");
561 
562 		pdata->slot[slot_id].wp_pin =
563 			of_get_named_gpio(cnp, "wp-gpios", 0);
564 	}
565 
566 	return pdata;
567 }
568 #else /* CONFIG_OF */
569 static inline struct mci_platform_data*
570 atmci_of_init(struct platform_device *dev)
571 {
572 	return ERR_PTR(-EINVAL);
573 }
574 #endif
575 
576 static inline unsigned int atmci_get_version(struct atmel_mci *host)
577 {
578 	return atmci_readl(host, ATMCI_VERSION) & 0x00000fff;
579 }
580 
581 static void atmci_timeout_timer(unsigned long data)
582 {
583 	struct atmel_mci *host;
584 
585 	host = (struct atmel_mci *)data;
586 
587 	dev_dbg(&host->pdev->dev, "software timeout\n");
588 
589 	if (host->mrq->cmd->data) {
590 		host->mrq->cmd->data->error = -ETIMEDOUT;
591 		host->data = NULL;
592 		/*
593 		 * With some SDIO modules, sometimes DMA transfer hangs. If
594 		 * stop_transfer() is not called then the DMA request is not
595 		 * removed, following ones are queued and never computed.
596 		 */
597 		if (host->state == STATE_DATA_XFER)
598 			host->stop_transfer(host);
599 	} else {
600 		host->mrq->cmd->error = -ETIMEDOUT;
601 		host->cmd = NULL;
602 	}
603 	host->need_reset = 1;
604 	host->state = STATE_END_REQUEST;
605 	smp_wmb();
606 	tasklet_schedule(&host->tasklet);
607 }
608 
609 static inline unsigned int atmci_ns_to_clocks(struct atmel_mci *host,
610 					unsigned int ns)
611 {
612 	/*
613 	 * It is easier here to use us instead of ns for the timeout,
614 	 * it prevents from overflows during calculation.
615 	 */
616 	unsigned int us = DIV_ROUND_UP(ns, 1000);
617 
618 	/* Maximum clock frequency is host->bus_hz/2 */
619 	return us * (DIV_ROUND_UP(host->bus_hz, 2000000));
620 }
621 
622 static void atmci_set_timeout(struct atmel_mci *host,
623 		struct atmel_mci_slot *slot, struct mmc_data *data)
624 {
625 	static unsigned	dtomul_to_shift[] = {
626 		0, 4, 7, 8, 10, 12, 16, 20
627 	};
628 	unsigned	timeout;
629 	unsigned	dtocyc;
630 	unsigned	dtomul;
631 
632 	timeout = atmci_ns_to_clocks(host, data->timeout_ns)
633 		+ data->timeout_clks;
634 
635 	for (dtomul = 0; dtomul < 8; dtomul++) {
636 		unsigned shift = dtomul_to_shift[dtomul];
637 		dtocyc = (timeout + (1 << shift) - 1) >> shift;
638 		if (dtocyc < 15)
639 			break;
640 	}
641 
642 	if (dtomul >= 8) {
643 		dtomul = 7;
644 		dtocyc = 15;
645 	}
646 
647 	dev_vdbg(&slot->mmc->class_dev, "setting timeout to %u cycles\n",
648 			dtocyc << dtomul_to_shift[dtomul]);
649 	atmci_writel(host, ATMCI_DTOR, (ATMCI_DTOMUL(dtomul) | ATMCI_DTOCYC(dtocyc)));
650 }
651 
652 /*
653  * Return mask with command flags to be enabled for this command.
654  */
655 static u32 atmci_prepare_command(struct mmc_host *mmc,
656 				 struct mmc_command *cmd)
657 {
658 	struct mmc_data	*data;
659 	u32		cmdr;
660 
661 	cmd->error = -EINPROGRESS;
662 
663 	cmdr = ATMCI_CMDR_CMDNB(cmd->opcode);
664 
665 	if (cmd->flags & MMC_RSP_PRESENT) {
666 		if (cmd->flags & MMC_RSP_136)
667 			cmdr |= ATMCI_CMDR_RSPTYP_136BIT;
668 		else
669 			cmdr |= ATMCI_CMDR_RSPTYP_48BIT;
670 	}
671 
672 	/*
673 	 * This should really be MAXLAT_5 for CMD2 and ACMD41, but
674 	 * it's too difficult to determine whether this is an ACMD or
675 	 * not. Better make it 64.
676 	 */
677 	cmdr |= ATMCI_CMDR_MAXLAT_64CYC;
678 
679 	if (mmc->ios.bus_mode == MMC_BUSMODE_OPENDRAIN)
680 		cmdr |= ATMCI_CMDR_OPDCMD;
681 
682 	data = cmd->data;
683 	if (data) {
684 		cmdr |= ATMCI_CMDR_START_XFER;
685 
686 		if (cmd->opcode == SD_IO_RW_EXTENDED) {
687 			cmdr |= ATMCI_CMDR_SDIO_BLOCK;
688 		} else {
689 			if (data->flags & MMC_DATA_STREAM)
690 				cmdr |= ATMCI_CMDR_STREAM;
691 			else if (data->blocks > 1)
692 				cmdr |= ATMCI_CMDR_MULTI_BLOCK;
693 			else
694 				cmdr |= ATMCI_CMDR_BLOCK;
695 		}
696 
697 		if (data->flags & MMC_DATA_READ)
698 			cmdr |= ATMCI_CMDR_TRDIR_READ;
699 	}
700 
701 	return cmdr;
702 }
703 
704 static void atmci_send_command(struct atmel_mci *host,
705 		struct mmc_command *cmd, u32 cmd_flags)
706 {
707 	WARN_ON(host->cmd);
708 	host->cmd = cmd;
709 
710 	dev_vdbg(&host->pdev->dev,
711 			"start command: ARGR=0x%08x CMDR=0x%08x\n",
712 			cmd->arg, cmd_flags);
713 
714 	atmci_writel(host, ATMCI_ARGR, cmd->arg);
715 	atmci_writel(host, ATMCI_CMDR, cmd_flags);
716 }
717 
718 static void atmci_send_stop_cmd(struct atmel_mci *host, struct mmc_data *data)
719 {
720 	dev_dbg(&host->pdev->dev, "send stop command\n");
721 	atmci_send_command(host, data->stop, host->stop_cmdr);
722 	atmci_writel(host, ATMCI_IER, ATMCI_CMDRDY);
723 }
724 
725 /*
726  * Configure given PDC buffer taking care of alignement issues.
727  * Update host->data_size and host->sg.
728  */
729 static void atmci_pdc_set_single_buf(struct atmel_mci *host,
730 	enum atmci_xfer_dir dir, enum atmci_pdc_buf buf_nb)
731 {
732 	u32 pointer_reg, counter_reg;
733 	unsigned int buf_size;
734 
735 	if (dir == XFER_RECEIVE) {
736 		pointer_reg = ATMEL_PDC_RPR;
737 		counter_reg = ATMEL_PDC_RCR;
738 	} else {
739 		pointer_reg = ATMEL_PDC_TPR;
740 		counter_reg = ATMEL_PDC_TCR;
741 	}
742 
743 	if (buf_nb == PDC_SECOND_BUF) {
744 		pointer_reg += ATMEL_PDC_SCND_BUF_OFF;
745 		counter_reg += ATMEL_PDC_SCND_BUF_OFF;
746 	}
747 
748 	if (!host->caps.has_rwproof) {
749 		buf_size = host->buf_size;
750 		atmci_writel(host, pointer_reg, host->buf_phys_addr);
751 	} else {
752 		buf_size = sg_dma_len(host->sg);
753 		atmci_writel(host, pointer_reg, sg_dma_address(host->sg));
754 	}
755 
756 	if (host->data_size <= buf_size) {
757 		if (host->data_size & 0x3) {
758 			/* If size is different from modulo 4, transfer bytes */
759 			atmci_writel(host, counter_reg, host->data_size);
760 			atmci_writel(host, ATMCI_MR, host->mode_reg | ATMCI_MR_PDCFBYTE);
761 		} else {
762 			/* Else transfer 32-bits words */
763 			atmci_writel(host, counter_reg, host->data_size / 4);
764 		}
765 		host->data_size = 0;
766 	} else {
767 		/* We assume the size of a page is 32-bits aligned */
768 		atmci_writel(host, counter_reg, sg_dma_len(host->sg) / 4);
769 		host->data_size -= sg_dma_len(host->sg);
770 		if (host->data_size)
771 			host->sg = sg_next(host->sg);
772 	}
773 }
774 
775 /*
776  * Configure PDC buffer according to the data size ie configuring one or two
777  * buffers. Don't use this function if you want to configure only the second
778  * buffer. In this case, use atmci_pdc_set_single_buf.
779  */
780 static void atmci_pdc_set_both_buf(struct atmel_mci *host, int dir)
781 {
782 	atmci_pdc_set_single_buf(host, dir, PDC_FIRST_BUF);
783 	if (host->data_size)
784 		atmci_pdc_set_single_buf(host, dir, PDC_SECOND_BUF);
785 }
786 
787 /*
788  * Unmap sg lists, called when transfer is finished.
789  */
790 static void atmci_pdc_cleanup(struct atmel_mci *host)
791 {
792 	struct mmc_data         *data = host->data;
793 
794 	if (data)
795 		dma_unmap_sg(&host->pdev->dev,
796 				data->sg, data->sg_len,
797 				((data->flags & MMC_DATA_WRITE)
798 				 ? DMA_TO_DEVICE : DMA_FROM_DEVICE));
799 }
800 
801 /*
802  * Disable PDC transfers. Update pending flags to EVENT_XFER_COMPLETE after
803  * having received ATMCI_TXBUFE or ATMCI_RXBUFF interrupt. Enable ATMCI_NOTBUSY
804  * interrupt needed for both transfer directions.
805  */
806 static void atmci_pdc_complete(struct atmel_mci *host)
807 {
808 	int transfer_size = host->data->blocks * host->data->blksz;
809 	int i;
810 
811 	atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
812 
813 	if ((!host->caps.has_rwproof)
814 	    && (host->data->flags & MMC_DATA_READ)) {
815 		if (host->caps.has_bad_data_ordering)
816 			for (i = 0; i < transfer_size; i++)
817 				host->buffer[i] = swab32(host->buffer[i]);
818 		sg_copy_from_buffer(host->data->sg, host->data->sg_len,
819 		                    host->buffer, transfer_size);
820 	}
821 
822 	atmci_pdc_cleanup(host);
823 
824 	dev_dbg(&host->pdev->dev, "(%s) set pending xfer complete\n", __func__);
825 	atmci_set_pending(host, EVENT_XFER_COMPLETE);
826 	tasklet_schedule(&host->tasklet);
827 }
828 
829 static void atmci_dma_cleanup(struct atmel_mci *host)
830 {
831 	struct mmc_data                 *data = host->data;
832 
833 	if (data)
834 		dma_unmap_sg(host->dma.chan->device->dev,
835 				data->sg, data->sg_len,
836 				((data->flags & MMC_DATA_WRITE)
837 				 ? DMA_TO_DEVICE : DMA_FROM_DEVICE));
838 }
839 
840 /*
841  * This function is called by the DMA driver from tasklet context.
842  */
843 static void atmci_dma_complete(void *arg)
844 {
845 	struct atmel_mci	*host = arg;
846 	struct mmc_data		*data = host->data;
847 
848 	dev_vdbg(&host->pdev->dev, "DMA complete\n");
849 
850 	if (host->caps.has_dma_conf_reg)
851 		/* Disable DMA hardware handshaking on MCI */
852 		atmci_writel(host, ATMCI_DMA, atmci_readl(host, ATMCI_DMA) & ~ATMCI_DMAEN);
853 
854 	atmci_dma_cleanup(host);
855 
856 	/*
857 	 * If the card was removed, data will be NULL. No point trying
858 	 * to send the stop command or waiting for NBUSY in this case.
859 	 */
860 	if (data) {
861 		dev_dbg(&host->pdev->dev,
862 		        "(%s) set pending xfer complete\n", __func__);
863 		atmci_set_pending(host, EVENT_XFER_COMPLETE);
864 		tasklet_schedule(&host->tasklet);
865 
866 		/*
867 		 * Regardless of what the documentation says, we have
868 		 * to wait for NOTBUSY even after block read
869 		 * operations.
870 		 *
871 		 * When the DMA transfer is complete, the controller
872 		 * may still be reading the CRC from the card, i.e.
873 		 * the data transfer is still in progress and we
874 		 * haven't seen all the potential error bits yet.
875 		 *
876 		 * The interrupt handler will schedule a different
877 		 * tasklet to finish things up when the data transfer
878 		 * is completely done.
879 		 *
880 		 * We may not complete the mmc request here anyway
881 		 * because the mmc layer may call back and cause us to
882 		 * violate the "don't submit new operations from the
883 		 * completion callback" rule of the dma engine
884 		 * framework.
885 		 */
886 		atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
887 	}
888 }
889 
890 /*
891  * Returns a mask of interrupt flags to be enabled after the whole
892  * request has been prepared.
893  */
894 static u32 atmci_prepare_data(struct atmel_mci *host, struct mmc_data *data)
895 {
896 	u32 iflags;
897 
898 	data->error = -EINPROGRESS;
899 
900 	host->sg = data->sg;
901 	host->sg_len = data->sg_len;
902 	host->data = data;
903 	host->data_chan = NULL;
904 
905 	iflags = ATMCI_DATA_ERROR_FLAGS;
906 
907 	/*
908 	 * Errata: MMC data write operation with less than 12
909 	 * bytes is impossible.
910 	 *
911 	 * Errata: MCI Transmit Data Register (TDR) FIFO
912 	 * corruption when length is not multiple of 4.
913 	 */
914 	if (data->blocks * data->blksz < 12
915 			|| (data->blocks * data->blksz) & 3)
916 		host->need_reset = true;
917 
918 	host->pio_offset = 0;
919 	if (data->flags & MMC_DATA_READ)
920 		iflags |= ATMCI_RXRDY;
921 	else
922 		iflags |= ATMCI_TXRDY;
923 
924 	return iflags;
925 }
926 
927 /*
928  * Set interrupt flags and set block length into the MCI mode register even
929  * if this value is also accessible in the MCI block register. It seems to be
930  * necessary before the High Speed MCI version. It also map sg and configure
931  * PDC registers.
932  */
933 static u32
934 atmci_prepare_data_pdc(struct atmel_mci *host, struct mmc_data *data)
935 {
936 	u32 iflags, tmp;
937 	unsigned int sg_len;
938 	enum dma_data_direction dir;
939 	int i;
940 
941 	data->error = -EINPROGRESS;
942 
943 	host->data = data;
944 	host->sg = data->sg;
945 	iflags = ATMCI_DATA_ERROR_FLAGS;
946 
947 	/* Enable pdc mode */
948 	atmci_writel(host, ATMCI_MR, host->mode_reg | ATMCI_MR_PDCMODE);
949 
950 	if (data->flags & MMC_DATA_READ) {
951 		dir = DMA_FROM_DEVICE;
952 		iflags |= ATMCI_ENDRX | ATMCI_RXBUFF;
953 	} else {
954 		dir = DMA_TO_DEVICE;
955 		iflags |= ATMCI_ENDTX | ATMCI_TXBUFE | ATMCI_BLKE;
956 	}
957 
958 	/* Set BLKLEN */
959 	tmp = atmci_readl(host, ATMCI_MR);
960 	tmp &= 0x0000ffff;
961 	tmp |= ATMCI_BLKLEN(data->blksz);
962 	atmci_writel(host, ATMCI_MR, tmp);
963 
964 	/* Configure PDC */
965 	host->data_size = data->blocks * data->blksz;
966 	sg_len = dma_map_sg(&host->pdev->dev, data->sg, data->sg_len, dir);
967 
968 	if ((!host->caps.has_rwproof)
969 	    && (host->data->flags & MMC_DATA_WRITE)) {
970 		sg_copy_to_buffer(host->data->sg, host->data->sg_len,
971 		                  host->buffer, host->data_size);
972 		if (host->caps.has_bad_data_ordering)
973 			for (i = 0; i < host->data_size; i++)
974 				host->buffer[i] = swab32(host->buffer[i]);
975 	}
976 
977 	if (host->data_size)
978 		atmci_pdc_set_both_buf(host,
979 			((dir == DMA_FROM_DEVICE) ? XFER_RECEIVE : XFER_TRANSMIT));
980 
981 	return iflags;
982 }
983 
984 static u32
985 atmci_prepare_data_dma(struct atmel_mci *host, struct mmc_data *data)
986 {
987 	struct dma_chan			*chan;
988 	struct dma_async_tx_descriptor	*desc;
989 	struct scatterlist		*sg;
990 	unsigned int			i;
991 	enum dma_data_direction		direction;
992 	enum dma_transfer_direction	slave_dirn;
993 	unsigned int			sglen;
994 	u32				maxburst;
995 	u32 iflags;
996 
997 	data->error = -EINPROGRESS;
998 
999 	WARN_ON(host->data);
1000 	host->sg = NULL;
1001 	host->data = data;
1002 
1003 	iflags = ATMCI_DATA_ERROR_FLAGS;
1004 
1005 	/*
1006 	 * We don't do DMA on "complex" transfers, i.e. with
1007 	 * non-word-aligned buffers or lengths. Also, we don't bother
1008 	 * with all the DMA setup overhead for short transfers.
1009 	 */
1010 	if (data->blocks * data->blksz < ATMCI_DMA_THRESHOLD)
1011 		return atmci_prepare_data(host, data);
1012 	if (data->blksz & 3)
1013 		return atmci_prepare_data(host, data);
1014 
1015 	for_each_sg(data->sg, sg, data->sg_len, i) {
1016 		if (sg->offset & 3 || sg->length & 3)
1017 			return atmci_prepare_data(host, data);
1018 	}
1019 
1020 	/* If we don't have a channel, we can't do DMA */
1021 	chan = host->dma.chan;
1022 	if (chan)
1023 		host->data_chan = chan;
1024 
1025 	if (!chan)
1026 		return -ENODEV;
1027 
1028 	if (data->flags & MMC_DATA_READ) {
1029 		direction = DMA_FROM_DEVICE;
1030 		host->dma_conf.direction = slave_dirn = DMA_DEV_TO_MEM;
1031 		maxburst = atmci_convert_chksize(host->dma_conf.src_maxburst);
1032 	} else {
1033 		direction = DMA_TO_DEVICE;
1034 		host->dma_conf.direction = slave_dirn = DMA_MEM_TO_DEV;
1035 		maxburst = atmci_convert_chksize(host->dma_conf.dst_maxburst);
1036 	}
1037 
1038 	if (host->caps.has_dma_conf_reg)
1039 		atmci_writel(host, ATMCI_DMA, ATMCI_DMA_CHKSIZE(maxburst) |
1040 			ATMCI_DMAEN);
1041 
1042 	sglen = dma_map_sg(chan->device->dev, data->sg,
1043 			data->sg_len, direction);
1044 
1045 	dmaengine_slave_config(chan, &host->dma_conf);
1046 	desc = dmaengine_prep_slave_sg(chan,
1047 			data->sg, sglen, slave_dirn,
1048 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1049 	if (!desc)
1050 		goto unmap_exit;
1051 
1052 	host->dma.data_desc = desc;
1053 	desc->callback = atmci_dma_complete;
1054 	desc->callback_param = host;
1055 
1056 	return iflags;
1057 unmap_exit:
1058 	dma_unmap_sg(chan->device->dev, data->sg, data->sg_len, direction);
1059 	return -ENOMEM;
1060 }
1061 
1062 static void
1063 atmci_submit_data(struct atmel_mci *host, struct mmc_data *data)
1064 {
1065 	return;
1066 }
1067 
1068 /*
1069  * Start PDC according to transfer direction.
1070  */
1071 static void
1072 atmci_submit_data_pdc(struct atmel_mci *host, struct mmc_data *data)
1073 {
1074 	if (data->flags & MMC_DATA_READ)
1075 		atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTEN);
1076 	else
1077 		atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN);
1078 }
1079 
1080 static void
1081 atmci_submit_data_dma(struct atmel_mci *host, struct mmc_data *data)
1082 {
1083 	struct dma_chan			*chan = host->data_chan;
1084 	struct dma_async_tx_descriptor	*desc = host->dma.data_desc;
1085 
1086 	if (chan) {
1087 		dmaengine_submit(desc);
1088 		dma_async_issue_pending(chan);
1089 	}
1090 }
1091 
1092 static void atmci_stop_transfer(struct atmel_mci *host)
1093 {
1094 	dev_dbg(&host->pdev->dev,
1095 	        "(%s) set pending xfer complete\n", __func__);
1096 	atmci_set_pending(host, EVENT_XFER_COMPLETE);
1097 	atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1098 }
1099 
1100 /*
1101  * Stop data transfer because error(s) occurred.
1102  */
1103 static void atmci_stop_transfer_pdc(struct atmel_mci *host)
1104 {
1105 	atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
1106 }
1107 
1108 static void atmci_stop_transfer_dma(struct atmel_mci *host)
1109 {
1110 	struct dma_chan *chan = host->data_chan;
1111 
1112 	if (chan) {
1113 		dmaengine_terminate_all(chan);
1114 		atmci_dma_cleanup(host);
1115 	} else {
1116 		/* Data transfer was stopped by the interrupt handler */
1117 		dev_dbg(&host->pdev->dev,
1118 		        "(%s) set pending xfer complete\n", __func__);
1119 		atmci_set_pending(host, EVENT_XFER_COMPLETE);
1120 		atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1121 	}
1122 }
1123 
1124 /*
1125  * Start a request: prepare data if needed, prepare the command and activate
1126  * interrupts.
1127  */
1128 static void atmci_start_request(struct atmel_mci *host,
1129 		struct atmel_mci_slot *slot)
1130 {
1131 	struct mmc_request	*mrq;
1132 	struct mmc_command	*cmd;
1133 	struct mmc_data		*data;
1134 	u32			iflags;
1135 	u32			cmdflags;
1136 
1137 	mrq = slot->mrq;
1138 	host->cur_slot = slot;
1139 	host->mrq = mrq;
1140 
1141 	host->pending_events = 0;
1142 	host->completed_events = 0;
1143 	host->cmd_status = 0;
1144 	host->data_status = 0;
1145 
1146 	dev_dbg(&host->pdev->dev, "start request: cmd %u\n", mrq->cmd->opcode);
1147 
1148 	if (host->need_reset || host->caps.need_reset_after_xfer) {
1149 		iflags = atmci_readl(host, ATMCI_IMR);
1150 		iflags &= (ATMCI_SDIOIRQA | ATMCI_SDIOIRQB);
1151 		atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
1152 		atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
1153 		atmci_writel(host, ATMCI_MR, host->mode_reg);
1154 		if (host->caps.has_cfg_reg)
1155 			atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1156 		atmci_writel(host, ATMCI_IER, iflags);
1157 		host->need_reset = false;
1158 	}
1159 	atmci_writel(host, ATMCI_SDCR, slot->sdc_reg);
1160 
1161 	iflags = atmci_readl(host, ATMCI_IMR);
1162 	if (iflags & ~(ATMCI_SDIOIRQA | ATMCI_SDIOIRQB))
1163 		dev_dbg(&slot->mmc->class_dev, "WARNING: IMR=0x%08x\n",
1164 				iflags);
1165 
1166 	if (unlikely(test_and_clear_bit(ATMCI_CARD_NEED_INIT, &slot->flags))) {
1167 		/* Send init sequence (74 clock cycles) */
1168 		atmci_writel(host, ATMCI_CMDR, ATMCI_CMDR_SPCMD_INIT);
1169 		while (!(atmci_readl(host, ATMCI_SR) & ATMCI_CMDRDY))
1170 			cpu_relax();
1171 	}
1172 	iflags = 0;
1173 	data = mrq->data;
1174 	if (data) {
1175 		atmci_set_timeout(host, slot, data);
1176 
1177 		/* Must set block count/size before sending command */
1178 		atmci_writel(host, ATMCI_BLKR, ATMCI_BCNT(data->blocks)
1179 				| ATMCI_BLKLEN(data->blksz));
1180 		dev_vdbg(&slot->mmc->class_dev, "BLKR=0x%08x\n",
1181 			ATMCI_BCNT(data->blocks) | ATMCI_BLKLEN(data->blksz));
1182 
1183 		iflags |= host->prepare_data(host, data);
1184 	}
1185 
1186 	iflags |= ATMCI_CMDRDY;
1187 	cmd = mrq->cmd;
1188 	cmdflags = atmci_prepare_command(slot->mmc, cmd);
1189 
1190 	/*
1191 	 * DMA transfer should be started before sending the command to avoid
1192 	 * unexpected errors especially for read operations in SDIO mode.
1193 	 * Unfortunately, in PDC mode, command has to be sent before starting
1194 	 * the transfer.
1195 	 */
1196 	if (host->submit_data != &atmci_submit_data_dma)
1197 		atmci_send_command(host, cmd, cmdflags);
1198 
1199 	if (data)
1200 		host->submit_data(host, data);
1201 
1202 	if (host->submit_data == &atmci_submit_data_dma)
1203 		atmci_send_command(host, cmd, cmdflags);
1204 
1205 	if (mrq->stop) {
1206 		host->stop_cmdr = atmci_prepare_command(slot->mmc, mrq->stop);
1207 		host->stop_cmdr |= ATMCI_CMDR_STOP_XFER;
1208 		if (!(data->flags & MMC_DATA_WRITE))
1209 			host->stop_cmdr |= ATMCI_CMDR_TRDIR_READ;
1210 		if (data->flags & MMC_DATA_STREAM)
1211 			host->stop_cmdr |= ATMCI_CMDR_STREAM;
1212 		else
1213 			host->stop_cmdr |= ATMCI_CMDR_MULTI_BLOCK;
1214 	}
1215 
1216 	/*
1217 	 * We could have enabled interrupts earlier, but I suspect
1218 	 * that would open up a nice can of interesting race
1219 	 * conditions (e.g. command and data complete, but stop not
1220 	 * prepared yet.)
1221 	 */
1222 	atmci_writel(host, ATMCI_IER, iflags);
1223 
1224 	mod_timer(&host->timer, jiffies +  msecs_to_jiffies(2000));
1225 }
1226 
1227 static void atmci_queue_request(struct atmel_mci *host,
1228 		struct atmel_mci_slot *slot, struct mmc_request *mrq)
1229 {
1230 	dev_vdbg(&slot->mmc->class_dev, "queue request: state=%d\n",
1231 			host->state);
1232 
1233 	spin_lock_bh(&host->lock);
1234 	slot->mrq = mrq;
1235 	if (host->state == STATE_IDLE) {
1236 		host->state = STATE_SENDING_CMD;
1237 		atmci_start_request(host, slot);
1238 	} else {
1239 		dev_dbg(&host->pdev->dev, "queue request\n");
1240 		list_add_tail(&slot->queue_node, &host->queue);
1241 	}
1242 	spin_unlock_bh(&host->lock);
1243 }
1244 
1245 static void atmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
1246 {
1247 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1248 	struct atmel_mci	*host = slot->host;
1249 	struct mmc_data		*data;
1250 
1251 	WARN_ON(slot->mrq);
1252 	dev_dbg(&host->pdev->dev, "MRQ: cmd %u\n", mrq->cmd->opcode);
1253 
1254 	/*
1255 	 * We may "know" the card is gone even though there's still an
1256 	 * electrical connection. If so, we really need to communicate
1257 	 * this to the MMC core since there won't be any more
1258 	 * interrupts as the card is completely removed. Otherwise,
1259 	 * the MMC core might believe the card is still there even
1260 	 * though the card was just removed very slowly.
1261 	 */
1262 	if (!test_bit(ATMCI_CARD_PRESENT, &slot->flags)) {
1263 		mrq->cmd->error = -ENOMEDIUM;
1264 		mmc_request_done(mmc, mrq);
1265 		return;
1266 	}
1267 
1268 	/* We don't support multiple blocks of weird lengths. */
1269 	data = mrq->data;
1270 	if (data && data->blocks > 1 && data->blksz & 3) {
1271 		mrq->cmd->error = -EINVAL;
1272 		mmc_request_done(mmc, mrq);
1273 	}
1274 
1275 	atmci_queue_request(host, slot, mrq);
1276 }
1277 
1278 static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
1279 {
1280 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1281 	struct atmel_mci	*host = slot->host;
1282 	unsigned int		i;
1283 	bool			unprepare_clk;
1284 
1285 	slot->sdc_reg &= ~ATMCI_SDCBUS_MASK;
1286 	switch (ios->bus_width) {
1287 	case MMC_BUS_WIDTH_1:
1288 		slot->sdc_reg |= ATMCI_SDCBUS_1BIT;
1289 		break;
1290 	case MMC_BUS_WIDTH_4:
1291 		slot->sdc_reg |= ATMCI_SDCBUS_4BIT;
1292 		break;
1293 	}
1294 
1295 	if (ios->clock) {
1296 		unsigned int clock_min = ~0U;
1297 		u32 clkdiv;
1298 
1299 		clk_prepare(host->mck);
1300 		unprepare_clk = true;
1301 
1302 		spin_lock_bh(&host->lock);
1303 		if (!host->mode_reg) {
1304 			clk_enable(host->mck);
1305 			unprepare_clk = false;
1306 			atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
1307 			atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
1308 			if (host->caps.has_cfg_reg)
1309 				atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1310 		}
1311 
1312 		/*
1313 		 * Use mirror of ios->clock to prevent race with mmc
1314 		 * core ios update when finding the minimum.
1315 		 */
1316 		slot->clock = ios->clock;
1317 		for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
1318 			if (host->slot[i] && host->slot[i]->clock
1319 					&& host->slot[i]->clock < clock_min)
1320 				clock_min = host->slot[i]->clock;
1321 		}
1322 
1323 		/* Calculate clock divider */
1324 		if (host->caps.has_odd_clk_div) {
1325 			clkdiv = DIV_ROUND_UP(host->bus_hz, clock_min) - 2;
1326 			if (clkdiv > 511) {
1327 				dev_warn(&mmc->class_dev,
1328 				         "clock %u too slow; using %lu\n",
1329 				         clock_min, host->bus_hz / (511 + 2));
1330 				clkdiv = 511;
1331 			}
1332 			host->mode_reg = ATMCI_MR_CLKDIV(clkdiv >> 1)
1333 			                 | ATMCI_MR_CLKODD(clkdiv & 1);
1334 		} else {
1335 			clkdiv = DIV_ROUND_UP(host->bus_hz, 2 * clock_min) - 1;
1336 			if (clkdiv > 255) {
1337 				dev_warn(&mmc->class_dev,
1338 				         "clock %u too slow; using %lu\n",
1339 				         clock_min, host->bus_hz / (2 * 256));
1340 				clkdiv = 255;
1341 			}
1342 			host->mode_reg = ATMCI_MR_CLKDIV(clkdiv);
1343 		}
1344 
1345 		/*
1346 		 * WRPROOF and RDPROOF prevent overruns/underruns by
1347 		 * stopping the clock when the FIFO is full/empty.
1348 		 * This state is not expected to last for long.
1349 		 */
1350 		if (host->caps.has_rwproof)
1351 			host->mode_reg |= (ATMCI_MR_WRPROOF | ATMCI_MR_RDPROOF);
1352 
1353 		if (host->caps.has_cfg_reg) {
1354 			/* setup High Speed mode in relation with card capacity */
1355 			if (ios->timing == MMC_TIMING_SD_HS)
1356 				host->cfg_reg |= ATMCI_CFG_HSMODE;
1357 			else
1358 				host->cfg_reg &= ~ATMCI_CFG_HSMODE;
1359 		}
1360 
1361 		if (list_empty(&host->queue)) {
1362 			atmci_writel(host, ATMCI_MR, host->mode_reg);
1363 			if (host->caps.has_cfg_reg)
1364 				atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1365 		} else {
1366 			host->need_clock_update = true;
1367 		}
1368 
1369 		spin_unlock_bh(&host->lock);
1370 	} else {
1371 		bool any_slot_active = false;
1372 
1373 		unprepare_clk = false;
1374 
1375 		spin_lock_bh(&host->lock);
1376 		slot->clock = 0;
1377 		for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
1378 			if (host->slot[i] && host->slot[i]->clock) {
1379 				any_slot_active = true;
1380 				break;
1381 			}
1382 		}
1383 		if (!any_slot_active) {
1384 			atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIDIS);
1385 			if (host->mode_reg) {
1386 				atmci_readl(host, ATMCI_MR);
1387 				clk_disable(host->mck);
1388 				unprepare_clk = true;
1389 			}
1390 			host->mode_reg = 0;
1391 		}
1392 		spin_unlock_bh(&host->lock);
1393 	}
1394 
1395 	if (unprepare_clk)
1396 		clk_unprepare(host->mck);
1397 
1398 	switch (ios->power_mode) {
1399 	case MMC_POWER_OFF:
1400 		if (!IS_ERR(mmc->supply.vmmc))
1401 			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, 0);
1402 		break;
1403 	case MMC_POWER_UP:
1404 		set_bit(ATMCI_CARD_NEED_INIT, &slot->flags);
1405 		if (!IS_ERR(mmc->supply.vmmc))
1406 			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, ios->vdd);
1407 		break;
1408 	default:
1409 		/*
1410 		 * TODO: None of the currently available AVR32-based
1411 		 * boards allow MMC power to be turned off. Implement
1412 		 * power control when this can be tested properly.
1413 		 *
1414 		 * We also need to hook this into the clock management
1415 		 * somehow so that newly inserted cards aren't
1416 		 * subjected to a fast clock before we have a chance
1417 		 * to figure out what the maximum rate is. Currently,
1418 		 * there's no way to avoid this, and there never will
1419 		 * be for boards that don't support power control.
1420 		 */
1421 		break;
1422 	}
1423 }
1424 
1425 static int atmci_get_ro(struct mmc_host *mmc)
1426 {
1427 	int			read_only = -ENOSYS;
1428 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1429 
1430 	if (gpio_is_valid(slot->wp_pin)) {
1431 		read_only = gpio_get_value(slot->wp_pin);
1432 		dev_dbg(&mmc->class_dev, "card is %s\n",
1433 				read_only ? "read-only" : "read-write");
1434 	}
1435 
1436 	return read_only;
1437 }
1438 
1439 static int atmci_get_cd(struct mmc_host *mmc)
1440 {
1441 	int			present = -ENOSYS;
1442 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1443 
1444 	if (gpio_is_valid(slot->detect_pin)) {
1445 		present = !(gpio_get_value(slot->detect_pin) ^
1446 			    slot->detect_is_active_high);
1447 		dev_dbg(&mmc->class_dev, "card is %spresent\n",
1448 				present ? "" : "not ");
1449 	}
1450 
1451 	return present;
1452 }
1453 
1454 static void atmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
1455 {
1456 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1457 	struct atmel_mci	*host = slot->host;
1458 
1459 	if (enable)
1460 		atmci_writel(host, ATMCI_IER, slot->sdio_irq);
1461 	else
1462 		atmci_writel(host, ATMCI_IDR, slot->sdio_irq);
1463 }
1464 
1465 static const struct mmc_host_ops atmci_ops = {
1466 	.request	= atmci_request,
1467 	.set_ios	= atmci_set_ios,
1468 	.get_ro		= atmci_get_ro,
1469 	.get_cd		= atmci_get_cd,
1470 	.enable_sdio_irq = atmci_enable_sdio_irq,
1471 };
1472 
1473 /* Called with host->lock held */
1474 static void atmci_request_end(struct atmel_mci *host, struct mmc_request *mrq)
1475 	__releases(&host->lock)
1476 	__acquires(&host->lock)
1477 {
1478 	struct atmel_mci_slot	*slot = NULL;
1479 	struct mmc_host		*prev_mmc = host->cur_slot->mmc;
1480 
1481 	WARN_ON(host->cmd || host->data);
1482 
1483 	/*
1484 	 * Update the MMC clock rate if necessary. This may be
1485 	 * necessary if set_ios() is called when a different slot is
1486 	 * busy transferring data.
1487 	 */
1488 	if (host->need_clock_update) {
1489 		atmci_writel(host, ATMCI_MR, host->mode_reg);
1490 		if (host->caps.has_cfg_reg)
1491 			atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1492 	}
1493 
1494 	host->cur_slot->mrq = NULL;
1495 	host->mrq = NULL;
1496 	if (!list_empty(&host->queue)) {
1497 		slot = list_entry(host->queue.next,
1498 				struct atmel_mci_slot, queue_node);
1499 		list_del(&slot->queue_node);
1500 		dev_vdbg(&host->pdev->dev, "list not empty: %s is next\n",
1501 				mmc_hostname(slot->mmc));
1502 		host->state = STATE_SENDING_CMD;
1503 		atmci_start_request(host, slot);
1504 	} else {
1505 		dev_vdbg(&host->pdev->dev, "list empty\n");
1506 		host->state = STATE_IDLE;
1507 	}
1508 
1509 	del_timer(&host->timer);
1510 
1511 	spin_unlock(&host->lock);
1512 	mmc_request_done(prev_mmc, mrq);
1513 	spin_lock(&host->lock);
1514 }
1515 
1516 static void atmci_command_complete(struct atmel_mci *host,
1517 			struct mmc_command *cmd)
1518 {
1519 	u32		status = host->cmd_status;
1520 
1521 	/* Read the response from the card (up to 16 bytes) */
1522 	cmd->resp[0] = atmci_readl(host, ATMCI_RSPR);
1523 	cmd->resp[1] = atmci_readl(host, ATMCI_RSPR);
1524 	cmd->resp[2] = atmci_readl(host, ATMCI_RSPR);
1525 	cmd->resp[3] = atmci_readl(host, ATMCI_RSPR);
1526 
1527 	if (status & ATMCI_RTOE)
1528 		cmd->error = -ETIMEDOUT;
1529 	else if ((cmd->flags & MMC_RSP_CRC) && (status & ATMCI_RCRCE))
1530 		cmd->error = -EILSEQ;
1531 	else if (status & (ATMCI_RINDE | ATMCI_RDIRE | ATMCI_RENDE))
1532 		cmd->error = -EIO;
1533 	else if (host->mrq->data && (host->mrq->data->blksz & 3)) {
1534 		if (host->caps.need_blksz_mul_4) {
1535 			cmd->error = -EINVAL;
1536 			host->need_reset = 1;
1537 		}
1538 	} else
1539 		cmd->error = 0;
1540 }
1541 
1542 static void atmci_detect_change(unsigned long data)
1543 {
1544 	struct atmel_mci_slot	*slot = (struct atmel_mci_slot *)data;
1545 	bool			present;
1546 	bool			present_old;
1547 
1548 	/*
1549 	 * atmci_cleanup_slot() sets the ATMCI_SHUTDOWN flag before
1550 	 * freeing the interrupt. We must not re-enable the interrupt
1551 	 * if it has been freed, and if we're shutting down, it
1552 	 * doesn't really matter whether the card is present or not.
1553 	 */
1554 	smp_rmb();
1555 	if (test_bit(ATMCI_SHUTDOWN, &slot->flags))
1556 		return;
1557 
1558 	enable_irq(gpio_to_irq(slot->detect_pin));
1559 	present = !(gpio_get_value(slot->detect_pin) ^
1560 		    slot->detect_is_active_high);
1561 	present_old = test_bit(ATMCI_CARD_PRESENT, &slot->flags);
1562 
1563 	dev_vdbg(&slot->mmc->class_dev, "detect change: %d (was %d)\n",
1564 			present, present_old);
1565 
1566 	if (present != present_old) {
1567 		struct atmel_mci	*host = slot->host;
1568 		struct mmc_request	*mrq;
1569 
1570 		dev_dbg(&slot->mmc->class_dev, "card %s\n",
1571 			present ? "inserted" : "removed");
1572 
1573 		spin_lock(&host->lock);
1574 
1575 		if (!present)
1576 			clear_bit(ATMCI_CARD_PRESENT, &slot->flags);
1577 		else
1578 			set_bit(ATMCI_CARD_PRESENT, &slot->flags);
1579 
1580 		/* Clean up queue if present */
1581 		mrq = slot->mrq;
1582 		if (mrq) {
1583 			if (mrq == host->mrq) {
1584 				/*
1585 				 * Reset controller to terminate any ongoing
1586 				 * commands or data transfers.
1587 				 */
1588 				atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
1589 				atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
1590 				atmci_writel(host, ATMCI_MR, host->mode_reg);
1591 				if (host->caps.has_cfg_reg)
1592 					atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1593 
1594 				host->data = NULL;
1595 				host->cmd = NULL;
1596 
1597 				switch (host->state) {
1598 				case STATE_IDLE:
1599 					break;
1600 				case STATE_SENDING_CMD:
1601 					mrq->cmd->error = -ENOMEDIUM;
1602 					if (mrq->data)
1603 						host->stop_transfer(host);
1604 					break;
1605 				case STATE_DATA_XFER:
1606 					mrq->data->error = -ENOMEDIUM;
1607 					host->stop_transfer(host);
1608 					break;
1609 				case STATE_WAITING_NOTBUSY:
1610 					mrq->data->error = -ENOMEDIUM;
1611 					break;
1612 				case STATE_SENDING_STOP:
1613 					mrq->stop->error = -ENOMEDIUM;
1614 					break;
1615 				case STATE_END_REQUEST:
1616 					break;
1617 				}
1618 
1619 				atmci_request_end(host, mrq);
1620 			} else {
1621 				list_del(&slot->queue_node);
1622 				mrq->cmd->error = -ENOMEDIUM;
1623 				if (mrq->data)
1624 					mrq->data->error = -ENOMEDIUM;
1625 				if (mrq->stop)
1626 					mrq->stop->error = -ENOMEDIUM;
1627 
1628 				spin_unlock(&host->lock);
1629 				mmc_request_done(slot->mmc, mrq);
1630 				spin_lock(&host->lock);
1631 			}
1632 		}
1633 		spin_unlock(&host->lock);
1634 
1635 		mmc_detect_change(slot->mmc, 0);
1636 	}
1637 }
1638 
1639 static void atmci_tasklet_func(unsigned long priv)
1640 {
1641 	struct atmel_mci	*host = (struct atmel_mci *)priv;
1642 	struct mmc_request	*mrq = host->mrq;
1643 	struct mmc_data		*data = host->data;
1644 	enum atmel_mci_state	state = host->state;
1645 	enum atmel_mci_state	prev_state;
1646 	u32			status;
1647 
1648 	spin_lock(&host->lock);
1649 
1650 	state = host->state;
1651 
1652 	dev_vdbg(&host->pdev->dev,
1653 		"tasklet: state %u pending/completed/mask %lx/%lx/%x\n",
1654 		state, host->pending_events, host->completed_events,
1655 		atmci_readl(host, ATMCI_IMR));
1656 
1657 	do {
1658 		prev_state = state;
1659 		dev_dbg(&host->pdev->dev, "FSM: state=%d\n", state);
1660 
1661 		switch (state) {
1662 		case STATE_IDLE:
1663 			break;
1664 
1665 		case STATE_SENDING_CMD:
1666 			/*
1667 			 * Command has been sent, we are waiting for command
1668 			 * ready. Then we have three next states possible:
1669 			 * END_REQUEST by default, WAITING_NOTBUSY if it's a
1670 			 * command needing it or DATA_XFER if there is data.
1671 			 */
1672 			dev_dbg(&host->pdev->dev, "FSM: cmd ready?\n");
1673 			if (!atmci_test_and_clear_pending(host,
1674 						EVENT_CMD_RDY))
1675 				break;
1676 
1677 			dev_dbg(&host->pdev->dev, "set completed cmd ready\n");
1678 			host->cmd = NULL;
1679 			atmci_set_completed(host, EVENT_CMD_RDY);
1680 			atmci_command_complete(host, mrq->cmd);
1681 			if (mrq->data) {
1682 				dev_dbg(&host->pdev->dev,
1683 				        "command with data transfer");
1684 				/*
1685 				 * If there is a command error don't start
1686 				 * data transfer.
1687 				 */
1688 				if (mrq->cmd->error) {
1689 					host->stop_transfer(host);
1690 					host->data = NULL;
1691 					atmci_writel(host, ATMCI_IDR,
1692 					             ATMCI_TXRDY | ATMCI_RXRDY
1693 					             | ATMCI_DATA_ERROR_FLAGS);
1694 					state = STATE_END_REQUEST;
1695 				} else
1696 					state = STATE_DATA_XFER;
1697 			} else if ((!mrq->data) && (mrq->cmd->flags & MMC_RSP_BUSY)) {
1698 				dev_dbg(&host->pdev->dev,
1699 				        "command response need waiting notbusy");
1700 				atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1701 				state = STATE_WAITING_NOTBUSY;
1702 			} else
1703 				state = STATE_END_REQUEST;
1704 
1705 			break;
1706 
1707 		case STATE_DATA_XFER:
1708 			if (atmci_test_and_clear_pending(host,
1709 						EVENT_DATA_ERROR)) {
1710 				dev_dbg(&host->pdev->dev, "set completed data error\n");
1711 				atmci_set_completed(host, EVENT_DATA_ERROR);
1712 				state = STATE_END_REQUEST;
1713 				break;
1714 			}
1715 
1716 			/*
1717 			 * A data transfer is in progress. The event expected
1718 			 * to move to the next state depends of data transfer
1719 			 * type (PDC or DMA). Once transfer done we can move
1720 			 * to the next step which is WAITING_NOTBUSY in write
1721 			 * case and directly SENDING_STOP in read case.
1722 			 */
1723 			dev_dbg(&host->pdev->dev, "FSM: xfer complete?\n");
1724 			if (!atmci_test_and_clear_pending(host,
1725 						EVENT_XFER_COMPLETE))
1726 				break;
1727 
1728 			dev_dbg(&host->pdev->dev,
1729 			        "(%s) set completed xfer complete\n",
1730 				__func__);
1731 			atmci_set_completed(host, EVENT_XFER_COMPLETE);
1732 
1733 			if (host->caps.need_notbusy_for_read_ops ||
1734 			   (host->data->flags & MMC_DATA_WRITE)) {
1735 				atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1736 				state = STATE_WAITING_NOTBUSY;
1737 			} else if (host->mrq->stop) {
1738 				atmci_writel(host, ATMCI_IER, ATMCI_CMDRDY);
1739 				atmci_send_stop_cmd(host, data);
1740 				state = STATE_SENDING_STOP;
1741 			} else {
1742 				host->data = NULL;
1743 				data->bytes_xfered = data->blocks * data->blksz;
1744 				data->error = 0;
1745 				state = STATE_END_REQUEST;
1746 			}
1747 			break;
1748 
1749 		case STATE_WAITING_NOTBUSY:
1750 			/*
1751 			 * We can be in the state for two reasons: a command
1752 			 * requiring waiting not busy signal (stop command
1753 			 * included) or a write operation. In the latest case,
1754 			 * we need to send a stop command.
1755 			 */
1756 			dev_dbg(&host->pdev->dev, "FSM: not busy?\n");
1757 			if (!atmci_test_and_clear_pending(host,
1758 						EVENT_NOTBUSY))
1759 				break;
1760 
1761 			dev_dbg(&host->pdev->dev, "set completed not busy\n");
1762 			atmci_set_completed(host, EVENT_NOTBUSY);
1763 
1764 			if (host->data) {
1765 				/*
1766 				 * For some commands such as CMD53, even if
1767 				 * there is data transfer, there is no stop
1768 				 * command to send.
1769 				 */
1770 				if (host->mrq->stop) {
1771 					atmci_writel(host, ATMCI_IER,
1772 					             ATMCI_CMDRDY);
1773 					atmci_send_stop_cmd(host, data);
1774 					state = STATE_SENDING_STOP;
1775 				} else {
1776 					host->data = NULL;
1777 					data->bytes_xfered = data->blocks
1778 					                     * data->blksz;
1779 					data->error = 0;
1780 					state = STATE_END_REQUEST;
1781 				}
1782 			} else
1783 				state = STATE_END_REQUEST;
1784 			break;
1785 
1786 		case STATE_SENDING_STOP:
1787 			/*
1788 			 * In this state, it is important to set host->data to
1789 			 * NULL (which is tested in the waiting notbusy state)
1790 			 * in order to go to the end request state instead of
1791 			 * sending stop again.
1792 			 */
1793 			dev_dbg(&host->pdev->dev, "FSM: cmd ready?\n");
1794 			if (!atmci_test_and_clear_pending(host,
1795 						EVENT_CMD_RDY))
1796 				break;
1797 
1798 			dev_dbg(&host->pdev->dev, "FSM: cmd ready\n");
1799 			host->cmd = NULL;
1800 			data->bytes_xfered = data->blocks * data->blksz;
1801 			data->error = 0;
1802 			atmci_command_complete(host, mrq->stop);
1803 			if (mrq->stop->error) {
1804 				host->stop_transfer(host);
1805 				atmci_writel(host, ATMCI_IDR,
1806 				             ATMCI_TXRDY | ATMCI_RXRDY
1807 				             | ATMCI_DATA_ERROR_FLAGS);
1808 				state = STATE_END_REQUEST;
1809 			} else {
1810 				atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1811 				state = STATE_WAITING_NOTBUSY;
1812 			}
1813 			host->data = NULL;
1814 			break;
1815 
1816 		case STATE_END_REQUEST:
1817 			atmci_writel(host, ATMCI_IDR, ATMCI_TXRDY | ATMCI_RXRDY
1818 			                   | ATMCI_DATA_ERROR_FLAGS);
1819 			status = host->data_status;
1820 			if (unlikely(status)) {
1821 				host->stop_transfer(host);
1822 				host->data = NULL;
1823 				if (data) {
1824 					if (status & ATMCI_DTOE) {
1825 						data->error = -ETIMEDOUT;
1826 					} else if (status & ATMCI_DCRCE) {
1827 						data->error = -EILSEQ;
1828 					} else {
1829 						data->error = -EIO;
1830 					}
1831 				}
1832 			}
1833 
1834 			atmci_request_end(host, host->mrq);
1835 			state = STATE_IDLE;
1836 			break;
1837 		}
1838 	} while (state != prev_state);
1839 
1840 	host->state = state;
1841 
1842 	spin_unlock(&host->lock);
1843 }
1844 
1845 static void atmci_read_data_pio(struct atmel_mci *host)
1846 {
1847 	struct scatterlist	*sg = host->sg;
1848 	void			*buf = sg_virt(sg);
1849 	unsigned int		offset = host->pio_offset;
1850 	struct mmc_data		*data = host->data;
1851 	u32			value;
1852 	u32			status;
1853 	unsigned int		nbytes = 0;
1854 
1855 	do {
1856 		value = atmci_readl(host, ATMCI_RDR);
1857 		if (likely(offset + 4 <= sg->length)) {
1858 			put_unaligned(value, (u32 *)(buf + offset));
1859 
1860 			offset += 4;
1861 			nbytes += 4;
1862 
1863 			if (offset == sg->length) {
1864 				flush_dcache_page(sg_page(sg));
1865 				host->sg = sg = sg_next(sg);
1866 				host->sg_len--;
1867 				if (!sg || !host->sg_len)
1868 					goto done;
1869 
1870 				offset = 0;
1871 				buf = sg_virt(sg);
1872 			}
1873 		} else {
1874 			unsigned int remaining = sg->length - offset;
1875 			memcpy(buf + offset, &value, remaining);
1876 			nbytes += remaining;
1877 
1878 			flush_dcache_page(sg_page(sg));
1879 			host->sg = sg = sg_next(sg);
1880 			host->sg_len--;
1881 			if (!sg || !host->sg_len)
1882 				goto done;
1883 
1884 			offset = 4 - remaining;
1885 			buf = sg_virt(sg);
1886 			memcpy(buf, (u8 *)&value + remaining, offset);
1887 			nbytes += offset;
1888 		}
1889 
1890 		status = atmci_readl(host, ATMCI_SR);
1891 		if (status & ATMCI_DATA_ERROR_FLAGS) {
1892 			atmci_writel(host, ATMCI_IDR, (ATMCI_NOTBUSY | ATMCI_RXRDY
1893 						| ATMCI_DATA_ERROR_FLAGS));
1894 			host->data_status = status;
1895 			data->bytes_xfered += nbytes;
1896 			return;
1897 		}
1898 	} while (status & ATMCI_RXRDY);
1899 
1900 	host->pio_offset = offset;
1901 	data->bytes_xfered += nbytes;
1902 
1903 	return;
1904 
1905 done:
1906 	atmci_writel(host, ATMCI_IDR, ATMCI_RXRDY);
1907 	atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1908 	data->bytes_xfered += nbytes;
1909 	smp_wmb();
1910 	atmci_set_pending(host, EVENT_XFER_COMPLETE);
1911 }
1912 
1913 static void atmci_write_data_pio(struct atmel_mci *host)
1914 {
1915 	struct scatterlist	*sg = host->sg;
1916 	void			*buf = sg_virt(sg);
1917 	unsigned int		offset = host->pio_offset;
1918 	struct mmc_data		*data = host->data;
1919 	u32			value;
1920 	u32			status;
1921 	unsigned int		nbytes = 0;
1922 
1923 	do {
1924 		if (likely(offset + 4 <= sg->length)) {
1925 			value = get_unaligned((u32 *)(buf + offset));
1926 			atmci_writel(host, ATMCI_TDR, value);
1927 
1928 			offset += 4;
1929 			nbytes += 4;
1930 			if (offset == sg->length) {
1931 				host->sg = sg = sg_next(sg);
1932 				host->sg_len--;
1933 				if (!sg || !host->sg_len)
1934 					goto done;
1935 
1936 				offset = 0;
1937 				buf = sg_virt(sg);
1938 			}
1939 		} else {
1940 			unsigned int remaining = sg->length - offset;
1941 
1942 			value = 0;
1943 			memcpy(&value, buf + offset, remaining);
1944 			nbytes += remaining;
1945 
1946 			host->sg = sg = sg_next(sg);
1947 			host->sg_len--;
1948 			if (!sg || !host->sg_len) {
1949 				atmci_writel(host, ATMCI_TDR, value);
1950 				goto done;
1951 			}
1952 
1953 			offset = 4 - remaining;
1954 			buf = sg_virt(sg);
1955 			memcpy((u8 *)&value + remaining, buf, offset);
1956 			atmci_writel(host, ATMCI_TDR, value);
1957 			nbytes += offset;
1958 		}
1959 
1960 		status = atmci_readl(host, ATMCI_SR);
1961 		if (status & ATMCI_DATA_ERROR_FLAGS) {
1962 			atmci_writel(host, ATMCI_IDR, (ATMCI_NOTBUSY | ATMCI_TXRDY
1963 						| ATMCI_DATA_ERROR_FLAGS));
1964 			host->data_status = status;
1965 			data->bytes_xfered += nbytes;
1966 			return;
1967 		}
1968 	} while (status & ATMCI_TXRDY);
1969 
1970 	host->pio_offset = offset;
1971 	data->bytes_xfered += nbytes;
1972 
1973 	return;
1974 
1975 done:
1976 	atmci_writel(host, ATMCI_IDR, ATMCI_TXRDY);
1977 	atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1978 	data->bytes_xfered += nbytes;
1979 	smp_wmb();
1980 	atmci_set_pending(host, EVENT_XFER_COMPLETE);
1981 }
1982 
1983 static void atmci_sdio_interrupt(struct atmel_mci *host, u32 status)
1984 {
1985 	int	i;
1986 
1987 	for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
1988 		struct atmel_mci_slot *slot = host->slot[i];
1989 		if (slot && (status & slot->sdio_irq)) {
1990 			mmc_signal_sdio_irq(slot->mmc);
1991 		}
1992 	}
1993 }
1994 
1995 
1996 static irqreturn_t atmci_interrupt(int irq, void *dev_id)
1997 {
1998 	struct atmel_mci	*host = dev_id;
1999 	u32			status, mask, pending;
2000 	unsigned int		pass_count = 0;
2001 
2002 	do {
2003 		status = atmci_readl(host, ATMCI_SR);
2004 		mask = atmci_readl(host, ATMCI_IMR);
2005 		pending = status & mask;
2006 		if (!pending)
2007 			break;
2008 
2009 		if (pending & ATMCI_DATA_ERROR_FLAGS) {
2010 			dev_dbg(&host->pdev->dev, "IRQ: data error\n");
2011 			atmci_writel(host, ATMCI_IDR, ATMCI_DATA_ERROR_FLAGS
2012 					| ATMCI_RXRDY | ATMCI_TXRDY
2013 					| ATMCI_ENDRX | ATMCI_ENDTX
2014 					| ATMCI_RXBUFF | ATMCI_TXBUFE);
2015 
2016 			host->data_status = status;
2017 			dev_dbg(&host->pdev->dev, "set pending data error\n");
2018 			smp_wmb();
2019 			atmci_set_pending(host, EVENT_DATA_ERROR);
2020 			tasklet_schedule(&host->tasklet);
2021 		}
2022 
2023 		if (pending & ATMCI_TXBUFE) {
2024 			dev_dbg(&host->pdev->dev, "IRQ: tx buffer empty\n");
2025 			atmci_writel(host, ATMCI_IDR, ATMCI_TXBUFE);
2026 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDTX);
2027 			/*
2028 			 * We can receive this interruption before having configured
2029 			 * the second pdc buffer, so we need to reconfigure first and
2030 			 * second buffers again
2031 			 */
2032 			if (host->data_size) {
2033 				atmci_pdc_set_both_buf(host, XFER_TRANSMIT);
2034 				atmci_writel(host, ATMCI_IER, ATMCI_ENDTX);
2035 				atmci_writel(host, ATMCI_IER, ATMCI_TXBUFE);
2036 			} else {
2037 				atmci_pdc_complete(host);
2038 			}
2039 		} else if (pending & ATMCI_ENDTX) {
2040 			dev_dbg(&host->pdev->dev, "IRQ: end of tx buffer\n");
2041 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDTX);
2042 
2043 			if (host->data_size) {
2044 				atmci_pdc_set_single_buf(host,
2045 						XFER_TRANSMIT, PDC_SECOND_BUF);
2046 				atmci_writel(host, ATMCI_IER, ATMCI_ENDTX);
2047 			}
2048 		}
2049 
2050 		if (pending & ATMCI_RXBUFF) {
2051 			dev_dbg(&host->pdev->dev, "IRQ: rx buffer full\n");
2052 			atmci_writel(host, ATMCI_IDR, ATMCI_RXBUFF);
2053 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDRX);
2054 			/*
2055 			 * We can receive this interruption before having configured
2056 			 * the second pdc buffer, so we need to reconfigure first and
2057 			 * second buffers again
2058 			 */
2059 			if (host->data_size) {
2060 				atmci_pdc_set_both_buf(host, XFER_RECEIVE);
2061 				atmci_writel(host, ATMCI_IER, ATMCI_ENDRX);
2062 				atmci_writel(host, ATMCI_IER, ATMCI_RXBUFF);
2063 			} else {
2064 				atmci_pdc_complete(host);
2065 			}
2066 		} else if (pending & ATMCI_ENDRX) {
2067 			dev_dbg(&host->pdev->dev, "IRQ: end of rx buffer\n");
2068 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDRX);
2069 
2070 			if (host->data_size) {
2071 				atmci_pdc_set_single_buf(host,
2072 						XFER_RECEIVE, PDC_SECOND_BUF);
2073 				atmci_writel(host, ATMCI_IER, ATMCI_ENDRX);
2074 			}
2075 		}
2076 
2077 		/*
2078 		 * First mci IPs, so mainly the ones having pdc, have some
2079 		 * issues with the notbusy signal. You can't get it after
2080 		 * data transmission if you have not sent a stop command.
2081 		 * The appropriate workaround is to use the BLKE signal.
2082 		 */
2083 		if (pending & ATMCI_BLKE) {
2084 			dev_dbg(&host->pdev->dev, "IRQ: blke\n");
2085 			atmci_writel(host, ATMCI_IDR, ATMCI_BLKE);
2086 			smp_wmb();
2087 			dev_dbg(&host->pdev->dev, "set pending notbusy\n");
2088 			atmci_set_pending(host, EVENT_NOTBUSY);
2089 			tasklet_schedule(&host->tasklet);
2090 		}
2091 
2092 		if (pending & ATMCI_NOTBUSY) {
2093 			dev_dbg(&host->pdev->dev, "IRQ: not_busy\n");
2094 			atmci_writel(host, ATMCI_IDR, ATMCI_NOTBUSY);
2095 			smp_wmb();
2096 			dev_dbg(&host->pdev->dev, "set pending notbusy\n");
2097 			atmci_set_pending(host, EVENT_NOTBUSY);
2098 			tasklet_schedule(&host->tasklet);
2099 		}
2100 
2101 		if (pending & ATMCI_RXRDY)
2102 			atmci_read_data_pio(host);
2103 		if (pending & ATMCI_TXRDY)
2104 			atmci_write_data_pio(host);
2105 
2106 		if (pending & ATMCI_CMDRDY) {
2107 			dev_dbg(&host->pdev->dev, "IRQ: cmd ready\n");
2108 			atmci_writel(host, ATMCI_IDR, ATMCI_CMDRDY);
2109 			host->cmd_status = status;
2110 			smp_wmb();
2111 			dev_dbg(&host->pdev->dev, "set pending cmd rdy\n");
2112 			atmci_set_pending(host, EVENT_CMD_RDY);
2113 			tasklet_schedule(&host->tasklet);
2114 		}
2115 
2116 		if (pending & (ATMCI_SDIOIRQA | ATMCI_SDIOIRQB))
2117 			atmci_sdio_interrupt(host, status);
2118 
2119 	} while (pass_count++ < 5);
2120 
2121 	return pass_count ? IRQ_HANDLED : IRQ_NONE;
2122 }
2123 
2124 static irqreturn_t atmci_detect_interrupt(int irq, void *dev_id)
2125 {
2126 	struct atmel_mci_slot	*slot = dev_id;
2127 
2128 	/*
2129 	 * Disable interrupts until the pin has stabilized and check
2130 	 * the state then. Use mod_timer() since we may be in the
2131 	 * middle of the timer routine when this interrupt triggers.
2132 	 */
2133 	disable_irq_nosync(irq);
2134 	mod_timer(&slot->detect_timer, jiffies + msecs_to_jiffies(20));
2135 
2136 	return IRQ_HANDLED;
2137 }
2138 
2139 static int __init atmci_init_slot(struct atmel_mci *host,
2140 		struct mci_slot_pdata *slot_data, unsigned int id,
2141 		u32 sdc_reg, u32 sdio_irq)
2142 {
2143 	struct mmc_host			*mmc;
2144 	struct atmel_mci_slot		*slot;
2145 
2146 	mmc = mmc_alloc_host(sizeof(struct atmel_mci_slot), &host->pdev->dev);
2147 	if (!mmc)
2148 		return -ENOMEM;
2149 
2150 	slot = mmc_priv(mmc);
2151 	slot->mmc = mmc;
2152 	slot->host = host;
2153 	slot->detect_pin = slot_data->detect_pin;
2154 	slot->wp_pin = slot_data->wp_pin;
2155 	slot->detect_is_active_high = slot_data->detect_is_active_high;
2156 	slot->sdc_reg = sdc_reg;
2157 	slot->sdio_irq = sdio_irq;
2158 
2159 	dev_dbg(&mmc->class_dev,
2160 	        "slot[%u]: bus_width=%u, detect_pin=%d, "
2161 		"detect_is_active_high=%s, wp_pin=%d\n",
2162 		id, slot_data->bus_width, slot_data->detect_pin,
2163 		slot_data->detect_is_active_high ? "true" : "false",
2164 		slot_data->wp_pin);
2165 
2166 	mmc->ops = &atmci_ops;
2167 	mmc->f_min = DIV_ROUND_UP(host->bus_hz, 512);
2168 	mmc->f_max = host->bus_hz / 2;
2169 	mmc->ocr_avail	= MMC_VDD_32_33 | MMC_VDD_33_34;
2170 	if (sdio_irq)
2171 		mmc->caps |= MMC_CAP_SDIO_IRQ;
2172 	if (host->caps.has_highspeed)
2173 		mmc->caps |= MMC_CAP_SD_HIGHSPEED;
2174 	/*
2175 	 * Without the read/write proof capability, it is strongly suggested to
2176 	 * use only one bit for data to prevent fifo underruns and overruns
2177 	 * which will corrupt data.
2178 	 */
2179 	if ((slot_data->bus_width >= 4) && host->caps.has_rwproof)
2180 		mmc->caps |= MMC_CAP_4_BIT_DATA;
2181 
2182 	if (atmci_get_version(host) < 0x200) {
2183 		mmc->max_segs = 256;
2184 		mmc->max_blk_size = 4095;
2185 		mmc->max_blk_count = 256;
2186 		mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
2187 		mmc->max_seg_size = mmc->max_blk_size * mmc->max_segs;
2188 	} else {
2189 		mmc->max_segs = 64;
2190 		mmc->max_req_size = 32768 * 512;
2191 		mmc->max_blk_size = 32768;
2192 		mmc->max_blk_count = 512;
2193 	}
2194 
2195 	/* Assume card is present initially */
2196 	set_bit(ATMCI_CARD_PRESENT, &slot->flags);
2197 	if (gpio_is_valid(slot->detect_pin)) {
2198 		if (gpio_request(slot->detect_pin, "mmc_detect")) {
2199 			dev_dbg(&mmc->class_dev, "no detect pin available\n");
2200 			slot->detect_pin = -EBUSY;
2201 		} else if (gpio_get_value(slot->detect_pin) ^
2202 				slot->detect_is_active_high) {
2203 			clear_bit(ATMCI_CARD_PRESENT, &slot->flags);
2204 		}
2205 	}
2206 
2207 	if (!gpio_is_valid(slot->detect_pin))
2208 		mmc->caps |= MMC_CAP_NEEDS_POLL;
2209 
2210 	if (gpio_is_valid(slot->wp_pin)) {
2211 		if (gpio_request(slot->wp_pin, "mmc_wp")) {
2212 			dev_dbg(&mmc->class_dev, "no WP pin available\n");
2213 			slot->wp_pin = -EBUSY;
2214 		}
2215 	}
2216 
2217 	host->slot[id] = slot;
2218 	mmc_regulator_get_supply(mmc);
2219 	mmc_add_host(mmc);
2220 
2221 	if (gpio_is_valid(slot->detect_pin)) {
2222 		int ret;
2223 
2224 		setup_timer(&slot->detect_timer, atmci_detect_change,
2225 				(unsigned long)slot);
2226 
2227 		ret = request_irq(gpio_to_irq(slot->detect_pin),
2228 				atmci_detect_interrupt,
2229 				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
2230 				"mmc-detect", slot);
2231 		if (ret) {
2232 			dev_dbg(&mmc->class_dev,
2233 				"could not request IRQ %d for detect pin\n",
2234 				gpio_to_irq(slot->detect_pin));
2235 			gpio_free(slot->detect_pin);
2236 			slot->detect_pin = -EBUSY;
2237 		}
2238 	}
2239 
2240 	atmci_init_debugfs(slot);
2241 
2242 	return 0;
2243 }
2244 
2245 static void __exit atmci_cleanup_slot(struct atmel_mci_slot *slot,
2246 		unsigned int id)
2247 {
2248 	/* Debugfs stuff is cleaned up by mmc core */
2249 
2250 	set_bit(ATMCI_SHUTDOWN, &slot->flags);
2251 	smp_wmb();
2252 
2253 	mmc_remove_host(slot->mmc);
2254 
2255 	if (gpio_is_valid(slot->detect_pin)) {
2256 		int pin = slot->detect_pin;
2257 
2258 		free_irq(gpio_to_irq(pin), slot);
2259 		del_timer_sync(&slot->detect_timer);
2260 		gpio_free(pin);
2261 	}
2262 	if (gpio_is_valid(slot->wp_pin))
2263 		gpio_free(slot->wp_pin);
2264 
2265 	slot->host->slot[id] = NULL;
2266 	mmc_free_host(slot->mmc);
2267 }
2268 
2269 static bool atmci_filter(struct dma_chan *chan, void *pdata)
2270 {
2271 	struct mci_platform_data *sl_pdata = pdata;
2272 	struct mci_dma_data *sl;
2273 
2274 	if (!sl_pdata)
2275 		return false;
2276 
2277 	sl = sl_pdata->dma_slave;
2278 	if (sl && find_slave_dev(sl) == chan->device->dev) {
2279 		chan->private = slave_data_ptr(sl);
2280 		return true;
2281 	} else {
2282 		return false;
2283 	}
2284 }
2285 
2286 static bool atmci_configure_dma(struct atmel_mci *host)
2287 {
2288 	struct mci_platform_data	*pdata;
2289 	dma_cap_mask_t mask;
2290 
2291 	if (host == NULL)
2292 		return false;
2293 
2294 	pdata = host->pdev->dev.platform_data;
2295 
2296 	dma_cap_zero(mask);
2297 	dma_cap_set(DMA_SLAVE, mask);
2298 
2299 	host->dma.chan = dma_request_slave_channel_compat(mask, atmci_filter, pdata,
2300 							  &host->pdev->dev, "rxtx");
2301 	if (!host->dma.chan) {
2302 		dev_warn(&host->pdev->dev, "no DMA channel available\n");
2303 		return false;
2304 	} else {
2305 		dev_info(&host->pdev->dev,
2306 					"using %s for DMA transfers\n",
2307 					dma_chan_name(host->dma.chan));
2308 
2309 		host->dma_conf.src_addr = host->mapbase + ATMCI_RDR;
2310 		host->dma_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
2311 		host->dma_conf.src_maxburst = 1;
2312 		host->dma_conf.dst_addr = host->mapbase + ATMCI_TDR;
2313 		host->dma_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
2314 		host->dma_conf.dst_maxburst = 1;
2315 		host->dma_conf.device_fc = false;
2316 		return true;
2317 	}
2318 }
2319 
2320 /*
2321  * HSMCI (High Speed MCI) module is not fully compatible with MCI module.
2322  * HSMCI provides DMA support and a new config register but no more supports
2323  * PDC.
2324  */
2325 static void __init atmci_get_cap(struct atmel_mci *host)
2326 {
2327 	unsigned int version;
2328 
2329 	version = atmci_get_version(host);
2330 	dev_info(&host->pdev->dev,
2331 			"version: 0x%x\n", version);
2332 
2333 	host->caps.has_dma_conf_reg = 0;
2334 	host->caps.has_pdc = ATMCI_PDC_CONNECTED;
2335 	host->caps.has_cfg_reg = 0;
2336 	host->caps.has_cstor_reg = 0;
2337 	host->caps.has_highspeed = 0;
2338 	host->caps.has_rwproof = 0;
2339 	host->caps.has_odd_clk_div = 0;
2340 	host->caps.has_bad_data_ordering = 1;
2341 	host->caps.need_reset_after_xfer = 1;
2342 	host->caps.need_blksz_mul_4 = 1;
2343 	host->caps.need_notbusy_for_read_ops = 0;
2344 
2345 	/* keep only major version number */
2346 	switch (version & 0xf00) {
2347 	case 0x500:
2348 		host->caps.has_odd_clk_div = 1;
2349 	case 0x400:
2350 	case 0x300:
2351 		host->caps.has_dma_conf_reg = 1;
2352 		host->caps.has_pdc = 0;
2353 		host->caps.has_cfg_reg = 1;
2354 		host->caps.has_cstor_reg = 1;
2355 		host->caps.has_highspeed = 1;
2356 	case 0x200:
2357 		host->caps.has_rwproof = 1;
2358 		host->caps.need_blksz_mul_4 = 0;
2359 		host->caps.need_notbusy_for_read_ops = 1;
2360 	case 0x100:
2361 		host->caps.has_bad_data_ordering = 0;
2362 		host->caps.need_reset_after_xfer = 0;
2363 	case 0x0:
2364 		break;
2365 	default:
2366 		host->caps.has_pdc = 0;
2367 		dev_warn(&host->pdev->dev,
2368 				"Unmanaged mci version, set minimum capabilities\n");
2369 		break;
2370 	}
2371 }
2372 
2373 static int __init atmci_probe(struct platform_device *pdev)
2374 {
2375 	struct mci_platform_data	*pdata;
2376 	struct atmel_mci		*host;
2377 	struct resource			*regs;
2378 	unsigned int			nr_slots;
2379 	int				irq;
2380 	int				ret;
2381 
2382 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2383 	if (!regs)
2384 		return -ENXIO;
2385 	pdata = pdev->dev.platform_data;
2386 	if (!pdata) {
2387 		pdata = atmci_of_init(pdev);
2388 		if (IS_ERR(pdata)) {
2389 			dev_err(&pdev->dev, "platform data not available\n");
2390 			return PTR_ERR(pdata);
2391 		}
2392 	}
2393 
2394 	irq = platform_get_irq(pdev, 0);
2395 	if (irq < 0)
2396 		return irq;
2397 
2398 	host = kzalloc(sizeof(struct atmel_mci), GFP_KERNEL);
2399 	if (!host)
2400 		return -ENOMEM;
2401 
2402 	host->pdev = pdev;
2403 	spin_lock_init(&host->lock);
2404 	INIT_LIST_HEAD(&host->queue);
2405 
2406 	host->mck = clk_get(&pdev->dev, "mci_clk");
2407 	if (IS_ERR(host->mck)) {
2408 		ret = PTR_ERR(host->mck);
2409 		goto err_clk_get;
2410 	}
2411 
2412 	ret = -ENOMEM;
2413 	host->regs = ioremap(regs->start, resource_size(regs));
2414 	if (!host->regs)
2415 		goto err_ioremap;
2416 
2417 	ret = clk_prepare_enable(host->mck);
2418 	if (ret)
2419 		goto err_request_irq;
2420 	atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
2421 	host->bus_hz = clk_get_rate(host->mck);
2422 	clk_disable_unprepare(host->mck);
2423 
2424 	host->mapbase = regs->start;
2425 
2426 	tasklet_init(&host->tasklet, atmci_tasklet_func, (unsigned long)host);
2427 
2428 	ret = request_irq(irq, atmci_interrupt, 0, dev_name(&pdev->dev), host);
2429 	if (ret)
2430 		goto err_request_irq;
2431 
2432 	/* Get MCI capabilities and set operations according to it */
2433 	atmci_get_cap(host);
2434 	if (atmci_configure_dma(host)) {
2435 		host->prepare_data = &atmci_prepare_data_dma;
2436 		host->submit_data = &atmci_submit_data_dma;
2437 		host->stop_transfer = &atmci_stop_transfer_dma;
2438 	} else if (host->caps.has_pdc) {
2439 		dev_info(&pdev->dev, "using PDC\n");
2440 		host->prepare_data = &atmci_prepare_data_pdc;
2441 		host->submit_data = &atmci_submit_data_pdc;
2442 		host->stop_transfer = &atmci_stop_transfer_pdc;
2443 	} else {
2444 		dev_info(&pdev->dev, "using PIO\n");
2445 		host->prepare_data = &atmci_prepare_data;
2446 		host->submit_data = &atmci_submit_data;
2447 		host->stop_transfer = &atmci_stop_transfer;
2448 	}
2449 
2450 	platform_set_drvdata(pdev, host);
2451 
2452 	setup_timer(&host->timer, atmci_timeout_timer, (unsigned long)host);
2453 
2454 	/* We need at least one slot to succeed */
2455 	nr_slots = 0;
2456 	ret = -ENODEV;
2457 	if (pdata->slot[0].bus_width) {
2458 		ret = atmci_init_slot(host, &pdata->slot[0],
2459 				0, ATMCI_SDCSEL_SLOT_A, ATMCI_SDIOIRQA);
2460 		if (!ret) {
2461 			nr_slots++;
2462 			host->buf_size = host->slot[0]->mmc->max_req_size;
2463 		}
2464 	}
2465 	if (pdata->slot[1].bus_width) {
2466 		ret = atmci_init_slot(host, &pdata->slot[1],
2467 				1, ATMCI_SDCSEL_SLOT_B, ATMCI_SDIOIRQB);
2468 		if (!ret) {
2469 			nr_slots++;
2470 			if (host->slot[1]->mmc->max_req_size > host->buf_size)
2471 				host->buf_size =
2472 					host->slot[1]->mmc->max_req_size;
2473 		}
2474 	}
2475 
2476 	if (!nr_slots) {
2477 		dev_err(&pdev->dev, "init failed: no slot defined\n");
2478 		goto err_init_slot;
2479 	}
2480 
2481 	if (!host->caps.has_rwproof) {
2482 		host->buffer = dma_alloc_coherent(&pdev->dev, host->buf_size,
2483 		                                  &host->buf_phys_addr,
2484 						  GFP_KERNEL);
2485 		if (!host->buffer) {
2486 			ret = -ENOMEM;
2487 			dev_err(&pdev->dev, "buffer allocation failed\n");
2488 			goto err_init_slot;
2489 		}
2490 	}
2491 
2492 	dev_info(&pdev->dev,
2493 			"Atmel MCI controller at 0x%08lx irq %d, %u slots\n",
2494 			host->mapbase, irq, nr_slots);
2495 
2496 	return 0;
2497 
2498 err_init_slot:
2499 	if (host->dma.chan)
2500 		dma_release_channel(host->dma.chan);
2501 	free_irq(irq, host);
2502 err_request_irq:
2503 	iounmap(host->regs);
2504 err_ioremap:
2505 	clk_put(host->mck);
2506 err_clk_get:
2507 	kfree(host);
2508 	return ret;
2509 }
2510 
2511 static int __exit atmci_remove(struct platform_device *pdev)
2512 {
2513 	struct atmel_mci	*host = platform_get_drvdata(pdev);
2514 	unsigned int		i;
2515 
2516 	if (host->buffer)
2517 		dma_free_coherent(&pdev->dev, host->buf_size,
2518 		                  host->buffer, host->buf_phys_addr);
2519 
2520 	for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
2521 		if (host->slot[i])
2522 			atmci_cleanup_slot(host->slot[i], i);
2523 	}
2524 
2525 	clk_prepare_enable(host->mck);
2526 	atmci_writel(host, ATMCI_IDR, ~0UL);
2527 	atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIDIS);
2528 	atmci_readl(host, ATMCI_SR);
2529 	clk_disable_unprepare(host->mck);
2530 
2531 	if (host->dma.chan)
2532 		dma_release_channel(host->dma.chan);
2533 
2534 	free_irq(platform_get_irq(pdev, 0), host);
2535 	iounmap(host->regs);
2536 
2537 	clk_put(host->mck);
2538 	kfree(host);
2539 
2540 	return 0;
2541 }
2542 
2543 static struct platform_driver atmci_driver = {
2544 	.remove		= __exit_p(atmci_remove),
2545 	.driver		= {
2546 		.name		= "atmel_mci",
2547 		.of_match_table	= of_match_ptr(atmci_dt_ids),
2548 	},
2549 };
2550 
2551 static int __init atmci_init(void)
2552 {
2553 	return platform_driver_probe(&atmci_driver, atmci_probe);
2554 }
2555 
2556 static void __exit atmci_exit(void)
2557 {
2558 	platform_driver_unregister(&atmci_driver);
2559 }
2560 
2561 late_initcall(atmci_init); /* try to load after dma driver when built-in */
2562 module_exit(atmci_exit);
2563 
2564 MODULE_DESCRIPTION("Atmel Multimedia Card Interface driver");
2565 MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
2566 MODULE_LICENSE("GPL v2");
2567