xref: /openbmc/linux/drivers/mmc/host/atmel-mci.c (revision 930beb5a)
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/io.h>
41 #include <asm/unaligned.h>
42 
43 #include "atmel-mci-regs.h"
44 
45 #define ATMCI_DATA_ERROR_FLAGS	(ATMCI_DCRCE | ATMCI_DTOE | ATMCI_OVRE | ATMCI_UNRE)
46 #define ATMCI_DMA_THRESHOLD	16
47 
48 enum {
49 	EVENT_CMD_RDY = 0,
50 	EVENT_XFER_COMPLETE,
51 	EVENT_NOTBUSY,
52 	EVENT_DATA_ERROR,
53 };
54 
55 enum atmel_mci_state {
56 	STATE_IDLE = 0,
57 	STATE_SENDING_CMD,
58 	STATE_DATA_XFER,
59 	STATE_WAITING_NOTBUSY,
60 	STATE_SENDING_STOP,
61 	STATE_END_REQUEST,
62 };
63 
64 enum atmci_xfer_dir {
65 	XFER_RECEIVE = 0,
66 	XFER_TRANSMIT,
67 };
68 
69 enum atmci_pdc_buf {
70 	PDC_FIRST_BUF = 0,
71 	PDC_SECOND_BUF,
72 };
73 
74 struct atmel_mci_caps {
75 	bool    has_dma_conf_reg;
76 	bool    has_pdc;
77 	bool    has_cfg_reg;
78 	bool    has_cstor_reg;
79 	bool    has_highspeed;
80 	bool    has_rwproof;
81 	bool	has_odd_clk_div;
82 	bool	has_bad_data_ordering;
83 	bool	need_reset_after_xfer;
84 	bool	need_blksz_mul_4;
85 	bool	need_notbusy_for_read_ops;
86 };
87 
88 struct atmel_mci_dma {
89 	struct dma_chan			*chan;
90 	struct dma_async_tx_descriptor	*data_desc;
91 };
92 
93 /**
94  * struct atmel_mci - MMC controller state shared between all slots
95  * @lock: Spinlock protecting the queue and associated data.
96  * @regs: Pointer to MMIO registers.
97  * @sg: Scatterlist entry currently being processed by PIO or PDC code.
98  * @pio_offset: Offset into the current scatterlist entry.
99  * @buffer: Buffer used if we don't have the r/w proof capability. We
100  *      don't have the time to switch pdc buffers so we have to use only
101  *      one buffer for the full transaction.
102  * @buf_size: size of the buffer.
103  * @phys_buf_addr: buffer address needed for pdc.
104  * @cur_slot: The slot which is currently using the controller.
105  * @mrq: The request currently being processed on @cur_slot,
106  *	or NULL if the controller is idle.
107  * @cmd: The command currently being sent to the card, or NULL.
108  * @data: The data currently being transferred, or NULL if no data
109  *	transfer is in progress.
110  * @data_size: just data->blocks * data->blksz.
111  * @dma: DMA client state.
112  * @data_chan: DMA channel being used for the current data transfer.
113  * @cmd_status: Snapshot of SR taken upon completion of the current
114  *	command. Only valid when EVENT_CMD_COMPLETE is pending.
115  * @data_status: Snapshot of SR taken upon completion of the current
116  *	data transfer. Only valid when EVENT_DATA_COMPLETE or
117  *	EVENT_DATA_ERROR is pending.
118  * @stop_cmdr: Value to be loaded into CMDR when the stop command is
119  *	to be sent.
120  * @tasklet: Tasklet running the request state machine.
121  * @pending_events: Bitmask of events flagged by the interrupt handler
122  *	to be processed by the tasklet.
123  * @completed_events: Bitmask of events which the state machine has
124  *	processed.
125  * @state: Tasklet state.
126  * @queue: List of slots waiting for access to the controller.
127  * @need_clock_update: Update the clock rate before the next request.
128  * @need_reset: Reset controller before next request.
129  * @timer: Timer to balance the data timeout error flag which cannot rise.
130  * @mode_reg: Value of the MR register.
131  * @cfg_reg: Value of the CFG register.
132  * @bus_hz: The rate of @mck in Hz. This forms the basis for MMC bus
133  *	rate and timeout calculations.
134  * @mapbase: Physical address of the MMIO registers.
135  * @mck: The peripheral bus clock hooked up to the MMC controller.
136  * @pdev: Platform device associated with the MMC controller.
137  * @slot: Slots sharing this MMC controller.
138  * @caps: MCI capabilities depending on MCI version.
139  * @prepare_data: function to setup MCI before data transfer which
140  * depends on MCI capabilities.
141  * @submit_data: function to start data transfer which depends on MCI
142  * capabilities.
143  * @stop_transfer: function to stop data transfer which depends on MCI
144  * capabilities.
145  *
146  * Locking
147  * =======
148  *
149  * @lock is a softirq-safe spinlock protecting @queue as well as
150  * @cur_slot, @mrq and @state. These must always be updated
151  * at the same time while holding @lock.
152  *
153  * @lock also protects mode_reg and need_clock_update since these are
154  * used to synchronize mode register updates with the queue
155  * processing.
156  *
157  * The @mrq field of struct atmel_mci_slot is also protected by @lock,
158  * and must always be written at the same time as the slot is added to
159  * @queue.
160  *
161  * @pending_events and @completed_events are accessed using atomic bit
162  * operations, so they don't need any locking.
163  *
164  * None of the fields touched by the interrupt handler need any
165  * locking. However, ordering is important: Before EVENT_DATA_ERROR or
166  * EVENT_DATA_COMPLETE is set in @pending_events, all data-related
167  * interrupts must be disabled and @data_status updated with a
168  * snapshot of SR. Similarly, before EVENT_CMD_COMPLETE is set, the
169  * CMDRDY interrupt must be disabled and @cmd_status updated with a
170  * snapshot of SR, and before EVENT_XFER_COMPLETE can be set, the
171  * bytes_xfered field of @data must be written. This is ensured by
172  * using barriers.
173  */
174 struct atmel_mci {
175 	spinlock_t		lock;
176 	void __iomem		*regs;
177 
178 	struct scatterlist	*sg;
179 	unsigned int		sg_len;
180 	unsigned int		pio_offset;
181 	unsigned int		*buffer;
182 	unsigned int		buf_size;
183 	dma_addr_t		buf_phys_addr;
184 
185 	struct atmel_mci_slot	*cur_slot;
186 	struct mmc_request	*mrq;
187 	struct mmc_command	*cmd;
188 	struct mmc_data		*data;
189 	unsigned int		data_size;
190 
191 	struct atmel_mci_dma	dma;
192 	struct dma_chan		*data_chan;
193 	struct dma_slave_config	dma_conf;
194 
195 	u32			cmd_status;
196 	u32			data_status;
197 	u32			stop_cmdr;
198 
199 	struct tasklet_struct	tasklet;
200 	unsigned long		pending_events;
201 	unsigned long		completed_events;
202 	enum atmel_mci_state	state;
203 	struct list_head	queue;
204 
205 	bool			need_clock_update;
206 	bool			need_reset;
207 	struct timer_list	timer;
208 	u32			mode_reg;
209 	u32			cfg_reg;
210 	unsigned long		bus_hz;
211 	unsigned long		mapbase;
212 	struct clk		*mck;
213 	struct platform_device	*pdev;
214 
215 	struct atmel_mci_slot	*slot[ATMCI_MAX_NR_SLOTS];
216 
217 	struct atmel_mci_caps   caps;
218 
219 	u32 (*prepare_data)(struct atmel_mci *host, struct mmc_data *data);
220 	void (*submit_data)(struct atmel_mci *host, struct mmc_data *data);
221 	void (*stop_transfer)(struct atmel_mci *host);
222 };
223 
224 /**
225  * struct atmel_mci_slot - MMC slot state
226  * @mmc: The mmc_host representing this slot.
227  * @host: The MMC controller this slot is using.
228  * @sdc_reg: Value of SDCR to be written before using this slot.
229  * @sdio_irq: SDIO irq mask for this slot.
230  * @mrq: mmc_request currently being processed or waiting to be
231  *	processed, or NULL when the slot is idle.
232  * @queue_node: List node for placing this node in the @queue list of
233  *	&struct atmel_mci.
234  * @clock: Clock rate configured by set_ios(). Protected by host->lock.
235  * @flags: Random state bits associated with the slot.
236  * @detect_pin: GPIO pin used for card detection, or negative if not
237  *	available.
238  * @wp_pin: GPIO pin used for card write protect sending, or negative
239  *	if not available.
240  * @detect_is_active_high: The state of the detect pin when it is active.
241  * @detect_timer: Timer used for debouncing @detect_pin interrupts.
242  */
243 struct atmel_mci_slot {
244 	struct mmc_host		*mmc;
245 	struct atmel_mci	*host;
246 
247 	u32			sdc_reg;
248 	u32			sdio_irq;
249 
250 	struct mmc_request	*mrq;
251 	struct list_head	queue_node;
252 
253 	unsigned int		clock;
254 	unsigned long		flags;
255 #define ATMCI_CARD_PRESENT	0
256 #define ATMCI_CARD_NEED_INIT	1
257 #define ATMCI_SHUTDOWN		2
258 
259 	int			detect_pin;
260 	int			wp_pin;
261 	bool			detect_is_active_high;
262 
263 	struct timer_list	detect_timer;
264 };
265 
266 #define atmci_test_and_clear_pending(host, event)		\
267 	test_and_clear_bit(event, &host->pending_events)
268 #define atmci_set_completed(host, event)			\
269 	set_bit(event, &host->completed_events)
270 #define atmci_set_pending(host, event)				\
271 	set_bit(event, &host->pending_events)
272 
273 /*
274  * The debugfs stuff below is mostly optimized away when
275  * CONFIG_DEBUG_FS is not set.
276  */
277 static int atmci_req_show(struct seq_file *s, void *v)
278 {
279 	struct atmel_mci_slot	*slot = s->private;
280 	struct mmc_request	*mrq;
281 	struct mmc_command	*cmd;
282 	struct mmc_command	*stop;
283 	struct mmc_data		*data;
284 
285 	/* Make sure we get a consistent snapshot */
286 	spin_lock_bh(&slot->host->lock);
287 	mrq = slot->mrq;
288 
289 	if (mrq) {
290 		cmd = mrq->cmd;
291 		data = mrq->data;
292 		stop = mrq->stop;
293 
294 		if (cmd)
295 			seq_printf(s,
296 				"CMD%u(0x%x) flg %x rsp %x %x %x %x err %d\n",
297 				cmd->opcode, cmd->arg, cmd->flags,
298 				cmd->resp[0], cmd->resp[1], cmd->resp[2],
299 				cmd->resp[3], cmd->error);
300 		if (data)
301 			seq_printf(s, "DATA %u / %u * %u flg %x err %d\n",
302 				data->bytes_xfered, data->blocks,
303 				data->blksz, data->flags, data->error);
304 		if (stop)
305 			seq_printf(s,
306 				"CMD%u(0x%x) flg %x rsp %x %x %x %x err %d\n",
307 				stop->opcode, stop->arg, stop->flags,
308 				stop->resp[0], stop->resp[1], stop->resp[2],
309 				stop->resp[3], stop->error);
310 	}
311 
312 	spin_unlock_bh(&slot->host->lock);
313 
314 	return 0;
315 }
316 
317 static int atmci_req_open(struct inode *inode, struct file *file)
318 {
319 	return single_open(file, atmci_req_show, inode->i_private);
320 }
321 
322 static const struct file_operations atmci_req_fops = {
323 	.owner		= THIS_MODULE,
324 	.open		= atmci_req_open,
325 	.read		= seq_read,
326 	.llseek		= seq_lseek,
327 	.release	= single_release,
328 };
329 
330 static void atmci_show_status_reg(struct seq_file *s,
331 		const char *regname, u32 value)
332 {
333 	static const char	*sr_bit[] = {
334 		[0]	= "CMDRDY",
335 		[1]	= "RXRDY",
336 		[2]	= "TXRDY",
337 		[3]	= "BLKE",
338 		[4]	= "DTIP",
339 		[5]	= "NOTBUSY",
340 		[6]	= "ENDRX",
341 		[7]	= "ENDTX",
342 		[8]	= "SDIOIRQA",
343 		[9]	= "SDIOIRQB",
344 		[12]	= "SDIOWAIT",
345 		[14]	= "RXBUFF",
346 		[15]	= "TXBUFE",
347 		[16]	= "RINDE",
348 		[17]	= "RDIRE",
349 		[18]	= "RCRCE",
350 		[19]	= "RENDE",
351 		[20]	= "RTOE",
352 		[21]	= "DCRCE",
353 		[22]	= "DTOE",
354 		[23]	= "CSTOE",
355 		[24]	= "BLKOVRE",
356 		[25]	= "DMADONE",
357 		[26]	= "FIFOEMPTY",
358 		[27]	= "XFRDONE",
359 		[30]	= "OVRE",
360 		[31]	= "UNRE",
361 	};
362 	unsigned int		i;
363 
364 	seq_printf(s, "%s:\t0x%08x", regname, value);
365 	for (i = 0; i < ARRAY_SIZE(sr_bit); i++) {
366 		if (value & (1 << i)) {
367 			if (sr_bit[i])
368 				seq_printf(s, " %s", sr_bit[i]);
369 			else
370 				seq_puts(s, " UNKNOWN");
371 		}
372 	}
373 	seq_putc(s, '\n');
374 }
375 
376 static int atmci_regs_show(struct seq_file *s, void *v)
377 {
378 	struct atmel_mci	*host = s->private;
379 	u32			*buf;
380 	int			ret = 0;
381 
382 
383 	buf = kmalloc(ATMCI_REGS_SIZE, GFP_KERNEL);
384 	if (!buf)
385 		return -ENOMEM;
386 
387 	/*
388 	 * Grab a more or less consistent snapshot. Note that we're
389 	 * not disabling interrupts, so IMR and SR may not be
390 	 * consistent.
391 	 */
392 	ret = clk_prepare_enable(host->mck);
393 	if (ret)
394 		goto out;
395 
396 	spin_lock_bh(&host->lock);
397 	memcpy_fromio(buf, host->regs, ATMCI_REGS_SIZE);
398 	spin_unlock_bh(&host->lock);
399 
400 	clk_disable_unprepare(host->mck);
401 
402 	seq_printf(s, "MR:\t0x%08x%s%s ",
403 			buf[ATMCI_MR / 4],
404 			buf[ATMCI_MR / 4] & ATMCI_MR_RDPROOF ? " RDPROOF" : "",
405 			buf[ATMCI_MR / 4] & ATMCI_MR_WRPROOF ? " WRPROOF" : "");
406 	if (host->caps.has_odd_clk_div)
407 		seq_printf(s, "{CLKDIV,CLKODD}=%u\n",
408 				((buf[ATMCI_MR / 4] & 0xff) << 1)
409 				| ((buf[ATMCI_MR / 4] >> 16) & 1));
410 	else
411 		seq_printf(s, "CLKDIV=%u\n",
412 				(buf[ATMCI_MR / 4] & 0xff));
413 	seq_printf(s, "DTOR:\t0x%08x\n", buf[ATMCI_DTOR / 4]);
414 	seq_printf(s, "SDCR:\t0x%08x\n", buf[ATMCI_SDCR / 4]);
415 	seq_printf(s, "ARGR:\t0x%08x\n", buf[ATMCI_ARGR / 4]);
416 	seq_printf(s, "BLKR:\t0x%08x BCNT=%u BLKLEN=%u\n",
417 			buf[ATMCI_BLKR / 4],
418 			buf[ATMCI_BLKR / 4] & 0xffff,
419 			(buf[ATMCI_BLKR / 4] >> 16) & 0xffff);
420 	if (host->caps.has_cstor_reg)
421 		seq_printf(s, "CSTOR:\t0x%08x\n", buf[ATMCI_CSTOR / 4]);
422 
423 	/* Don't read RSPR and RDR; it will consume the data there */
424 
425 	atmci_show_status_reg(s, "SR", buf[ATMCI_SR / 4]);
426 	atmci_show_status_reg(s, "IMR", buf[ATMCI_IMR / 4]);
427 
428 	if (host->caps.has_dma_conf_reg) {
429 		u32 val;
430 
431 		val = buf[ATMCI_DMA / 4];
432 		seq_printf(s, "DMA:\t0x%08x OFFSET=%u CHKSIZE=%u%s\n",
433 				val, val & 3,
434 				((val >> 4) & 3) ?
435 					1 << (((val >> 4) & 3) + 1) : 1,
436 				val & ATMCI_DMAEN ? " DMAEN" : "");
437 	}
438 	if (host->caps.has_cfg_reg) {
439 		u32 val;
440 
441 		val = buf[ATMCI_CFG / 4];
442 		seq_printf(s, "CFG:\t0x%08x%s%s%s%s\n",
443 				val,
444 				val & ATMCI_CFG_FIFOMODE_1DATA ? " FIFOMODE_ONE_DATA" : "",
445 				val & ATMCI_CFG_FERRCTRL_COR ? " FERRCTRL_CLEAR_ON_READ" : "",
446 				val & ATMCI_CFG_HSMODE ? " HSMODE" : "",
447 				val & ATMCI_CFG_LSYNC ? " LSYNC" : "");
448 	}
449 
450 out:
451 	kfree(buf);
452 
453 	return ret;
454 }
455 
456 static int atmci_regs_open(struct inode *inode, struct file *file)
457 {
458 	return single_open(file, atmci_regs_show, inode->i_private);
459 }
460 
461 static const struct file_operations atmci_regs_fops = {
462 	.owner		= THIS_MODULE,
463 	.open		= atmci_regs_open,
464 	.read		= seq_read,
465 	.llseek		= seq_lseek,
466 	.release	= single_release,
467 };
468 
469 static void atmci_init_debugfs(struct atmel_mci_slot *slot)
470 {
471 	struct mmc_host		*mmc = slot->mmc;
472 	struct atmel_mci	*host = slot->host;
473 	struct dentry		*root;
474 	struct dentry		*node;
475 
476 	root = mmc->debugfs_root;
477 	if (!root)
478 		return;
479 
480 	node = debugfs_create_file("regs", S_IRUSR, root, host,
481 			&atmci_regs_fops);
482 	if (IS_ERR(node))
483 		return;
484 	if (!node)
485 		goto err;
486 
487 	node = debugfs_create_file("req", S_IRUSR, root, slot, &atmci_req_fops);
488 	if (!node)
489 		goto err;
490 
491 	node = debugfs_create_u32("state", S_IRUSR, root, (u32 *)&host->state);
492 	if (!node)
493 		goto err;
494 
495 	node = debugfs_create_x32("pending_events", S_IRUSR, root,
496 				     (u32 *)&host->pending_events);
497 	if (!node)
498 		goto err;
499 
500 	node = debugfs_create_x32("completed_events", S_IRUSR, root,
501 				     (u32 *)&host->completed_events);
502 	if (!node)
503 		goto err;
504 
505 	return;
506 
507 err:
508 	dev_err(&mmc->class_dev, "failed to initialize debugfs for slot\n");
509 }
510 
511 #if defined(CONFIG_OF)
512 static const struct of_device_id atmci_dt_ids[] = {
513 	{ .compatible = "atmel,hsmci" },
514 	{ /* sentinel */ }
515 };
516 
517 MODULE_DEVICE_TABLE(of, atmci_dt_ids);
518 
519 static struct mci_platform_data*
520 atmci_of_init(struct platform_device *pdev)
521 {
522 	struct device_node *np = pdev->dev.of_node;
523 	struct device_node *cnp;
524 	struct mci_platform_data *pdata;
525 	u32 slot_id;
526 
527 	if (!np) {
528 		dev_err(&pdev->dev, "device node not found\n");
529 		return ERR_PTR(-EINVAL);
530 	}
531 
532 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
533 	if (!pdata) {
534 		dev_err(&pdev->dev, "could not allocate memory for pdata\n");
535 		return ERR_PTR(-ENOMEM);
536 	}
537 
538 	for_each_child_of_node(np, cnp) {
539 		if (of_property_read_u32(cnp, "reg", &slot_id)) {
540 			dev_warn(&pdev->dev, "reg property is missing for %s\n",
541 				 cnp->full_name);
542 			continue;
543 		}
544 
545 		if (slot_id >= ATMCI_MAX_NR_SLOTS) {
546 			dev_warn(&pdev->dev, "can't have more than %d slots\n",
547 			         ATMCI_MAX_NR_SLOTS);
548 			break;
549 		}
550 
551 		if (of_property_read_u32(cnp, "bus-width",
552 		                         &pdata->slot[slot_id].bus_width))
553 			pdata->slot[slot_id].bus_width = 1;
554 
555 		pdata->slot[slot_id].detect_pin =
556 			of_get_named_gpio(cnp, "cd-gpios", 0);
557 
558 		pdata->slot[slot_id].detect_is_active_high =
559 			of_property_read_bool(cnp, "cd-inverted");
560 
561 		pdata->slot[slot_id].wp_pin =
562 			of_get_named_gpio(cnp, "wp-gpios", 0);
563 	}
564 
565 	return pdata;
566 }
567 #else /* CONFIG_OF */
568 static inline struct mci_platform_data*
569 atmci_of_init(struct platform_device *dev)
570 {
571 	return ERR_PTR(-EINVAL);
572 }
573 #endif
574 
575 static inline unsigned int atmci_get_version(struct atmel_mci *host)
576 {
577 	return atmci_readl(host, ATMCI_VERSION) & 0x00000fff;
578 }
579 
580 static void atmci_timeout_timer(unsigned long data)
581 {
582 	struct atmel_mci *host;
583 
584 	host = (struct atmel_mci *)data;
585 
586 	dev_dbg(&host->pdev->dev, "software timeout\n");
587 
588 	if (host->mrq->cmd->data) {
589 		host->mrq->cmd->data->error = -ETIMEDOUT;
590 		host->data = NULL;
591 		/*
592 		 * With some SDIO modules, sometimes DMA transfer hangs. If
593 		 * stop_transfer() is not called then the DMA request is not
594 		 * removed, following ones are queued and never computed.
595 		 */
596 		if (host->state == STATE_DATA_XFER)
597 			host->stop_transfer(host);
598 	} else {
599 		host->mrq->cmd->error = -ETIMEDOUT;
600 		host->cmd = NULL;
601 	}
602 	host->need_reset = 1;
603 	host->state = STATE_END_REQUEST;
604 	smp_wmb();
605 	tasklet_schedule(&host->tasklet);
606 }
607 
608 static inline unsigned int atmci_ns_to_clocks(struct atmel_mci *host,
609 					unsigned int ns)
610 {
611 	/*
612 	 * It is easier here to use us instead of ns for the timeout,
613 	 * it prevents from overflows during calculation.
614 	 */
615 	unsigned int us = DIV_ROUND_UP(ns, 1000);
616 
617 	/* Maximum clock frequency is host->bus_hz/2 */
618 	return us * (DIV_ROUND_UP(host->bus_hz, 2000000));
619 }
620 
621 static void atmci_set_timeout(struct atmel_mci *host,
622 		struct atmel_mci_slot *slot, struct mmc_data *data)
623 {
624 	static unsigned	dtomul_to_shift[] = {
625 		0, 4, 7, 8, 10, 12, 16, 20
626 	};
627 	unsigned	timeout;
628 	unsigned	dtocyc;
629 	unsigned	dtomul;
630 
631 	timeout = atmci_ns_to_clocks(host, data->timeout_ns)
632 		+ data->timeout_clks;
633 
634 	for (dtomul = 0; dtomul < 8; dtomul++) {
635 		unsigned shift = dtomul_to_shift[dtomul];
636 		dtocyc = (timeout + (1 << shift) - 1) >> shift;
637 		if (dtocyc < 15)
638 			break;
639 	}
640 
641 	if (dtomul >= 8) {
642 		dtomul = 7;
643 		dtocyc = 15;
644 	}
645 
646 	dev_vdbg(&slot->mmc->class_dev, "setting timeout to %u cycles\n",
647 			dtocyc << dtomul_to_shift[dtomul]);
648 	atmci_writel(host, ATMCI_DTOR, (ATMCI_DTOMUL(dtomul) | ATMCI_DTOCYC(dtocyc)));
649 }
650 
651 /*
652  * Return mask with command flags to be enabled for this command.
653  */
654 static u32 atmci_prepare_command(struct mmc_host *mmc,
655 				 struct mmc_command *cmd)
656 {
657 	struct mmc_data	*data;
658 	u32		cmdr;
659 
660 	cmd->error = -EINPROGRESS;
661 
662 	cmdr = ATMCI_CMDR_CMDNB(cmd->opcode);
663 
664 	if (cmd->flags & MMC_RSP_PRESENT) {
665 		if (cmd->flags & MMC_RSP_136)
666 			cmdr |= ATMCI_CMDR_RSPTYP_136BIT;
667 		else
668 			cmdr |= ATMCI_CMDR_RSPTYP_48BIT;
669 	}
670 
671 	/*
672 	 * This should really be MAXLAT_5 for CMD2 and ACMD41, but
673 	 * it's too difficult to determine whether this is an ACMD or
674 	 * not. Better make it 64.
675 	 */
676 	cmdr |= ATMCI_CMDR_MAXLAT_64CYC;
677 
678 	if (mmc->ios.bus_mode == MMC_BUSMODE_OPENDRAIN)
679 		cmdr |= ATMCI_CMDR_OPDCMD;
680 
681 	data = cmd->data;
682 	if (data) {
683 		cmdr |= ATMCI_CMDR_START_XFER;
684 
685 		if (cmd->opcode == SD_IO_RW_EXTENDED) {
686 			cmdr |= ATMCI_CMDR_SDIO_BLOCK;
687 		} else {
688 			if (data->flags & MMC_DATA_STREAM)
689 				cmdr |= ATMCI_CMDR_STREAM;
690 			else if (data->blocks > 1)
691 				cmdr |= ATMCI_CMDR_MULTI_BLOCK;
692 			else
693 				cmdr |= ATMCI_CMDR_BLOCK;
694 		}
695 
696 		if (data->flags & MMC_DATA_READ)
697 			cmdr |= ATMCI_CMDR_TRDIR_READ;
698 	}
699 
700 	return cmdr;
701 }
702 
703 static void atmci_send_command(struct atmel_mci *host,
704 		struct mmc_command *cmd, u32 cmd_flags)
705 {
706 	WARN_ON(host->cmd);
707 	host->cmd = cmd;
708 
709 	dev_vdbg(&host->pdev->dev,
710 			"start command: ARGR=0x%08x CMDR=0x%08x\n",
711 			cmd->arg, cmd_flags);
712 
713 	atmci_writel(host, ATMCI_ARGR, cmd->arg);
714 	atmci_writel(host, ATMCI_CMDR, cmd_flags);
715 }
716 
717 static void atmci_send_stop_cmd(struct atmel_mci *host, struct mmc_data *data)
718 {
719 	dev_dbg(&host->pdev->dev, "send stop command\n");
720 	atmci_send_command(host, data->stop, host->stop_cmdr);
721 	atmci_writel(host, ATMCI_IER, ATMCI_CMDRDY);
722 }
723 
724 /*
725  * Configure given PDC buffer taking care of alignement issues.
726  * Update host->data_size and host->sg.
727  */
728 static void atmci_pdc_set_single_buf(struct atmel_mci *host,
729 	enum atmci_xfer_dir dir, enum atmci_pdc_buf buf_nb)
730 {
731 	u32 pointer_reg, counter_reg;
732 	unsigned int buf_size;
733 
734 	if (dir == XFER_RECEIVE) {
735 		pointer_reg = ATMEL_PDC_RPR;
736 		counter_reg = ATMEL_PDC_RCR;
737 	} else {
738 		pointer_reg = ATMEL_PDC_TPR;
739 		counter_reg = ATMEL_PDC_TCR;
740 	}
741 
742 	if (buf_nb == PDC_SECOND_BUF) {
743 		pointer_reg += ATMEL_PDC_SCND_BUF_OFF;
744 		counter_reg += ATMEL_PDC_SCND_BUF_OFF;
745 	}
746 
747 	if (!host->caps.has_rwproof) {
748 		buf_size = host->buf_size;
749 		atmci_writel(host, pointer_reg, host->buf_phys_addr);
750 	} else {
751 		buf_size = sg_dma_len(host->sg);
752 		atmci_writel(host, pointer_reg, sg_dma_address(host->sg));
753 	}
754 
755 	if (host->data_size <= buf_size) {
756 		if (host->data_size & 0x3) {
757 			/* If size is different from modulo 4, transfer bytes */
758 			atmci_writel(host, counter_reg, host->data_size);
759 			atmci_writel(host, ATMCI_MR, host->mode_reg | ATMCI_MR_PDCFBYTE);
760 		} else {
761 			/* Else transfer 32-bits words */
762 			atmci_writel(host, counter_reg, host->data_size / 4);
763 		}
764 		host->data_size = 0;
765 	} else {
766 		/* We assume the size of a page is 32-bits aligned */
767 		atmci_writel(host, counter_reg, sg_dma_len(host->sg) / 4);
768 		host->data_size -= sg_dma_len(host->sg);
769 		if (host->data_size)
770 			host->sg = sg_next(host->sg);
771 	}
772 }
773 
774 /*
775  * Configure PDC buffer according to the data size ie configuring one or two
776  * buffers. Don't use this function if you want to configure only the second
777  * buffer. In this case, use atmci_pdc_set_single_buf.
778  */
779 static void atmci_pdc_set_both_buf(struct atmel_mci *host, int dir)
780 {
781 	atmci_pdc_set_single_buf(host, dir, PDC_FIRST_BUF);
782 	if (host->data_size)
783 		atmci_pdc_set_single_buf(host, dir, PDC_SECOND_BUF);
784 }
785 
786 /*
787  * Unmap sg lists, called when transfer is finished.
788  */
789 static void atmci_pdc_cleanup(struct atmel_mci *host)
790 {
791 	struct mmc_data         *data = host->data;
792 
793 	if (data)
794 		dma_unmap_sg(&host->pdev->dev,
795 				data->sg, data->sg_len,
796 				((data->flags & MMC_DATA_WRITE)
797 				 ? DMA_TO_DEVICE : DMA_FROM_DEVICE));
798 }
799 
800 /*
801  * Disable PDC transfers. Update pending flags to EVENT_XFER_COMPLETE after
802  * having received ATMCI_TXBUFE or ATMCI_RXBUFF interrupt. Enable ATMCI_NOTBUSY
803  * interrupt needed for both transfer directions.
804  */
805 static void atmci_pdc_complete(struct atmel_mci *host)
806 {
807 	int transfer_size = host->data->blocks * host->data->blksz;
808 	int i;
809 
810 	atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
811 
812 	if ((!host->caps.has_rwproof)
813 	    && (host->data->flags & MMC_DATA_READ)) {
814 		if (host->caps.has_bad_data_ordering)
815 			for (i = 0; i < transfer_size; i++)
816 				host->buffer[i] = swab32(host->buffer[i]);
817 		sg_copy_from_buffer(host->data->sg, host->data->sg_len,
818 		                    host->buffer, transfer_size);
819 	}
820 
821 	atmci_pdc_cleanup(host);
822 
823 	/*
824 	 * If the card was removed, data will be NULL. No point trying
825 	 * to send the stop command or waiting for NBUSY in this case.
826 	 */
827 	if (host->data) {
828 		dev_dbg(&host->pdev->dev,
829 		        "(%s) set pending xfer complete\n", __func__);
830 		atmci_set_pending(host, EVENT_XFER_COMPLETE);
831 		tasklet_schedule(&host->tasklet);
832 	}
833 }
834 
835 static void atmci_dma_cleanup(struct atmel_mci *host)
836 {
837 	struct mmc_data                 *data = host->data;
838 
839 	if (data)
840 		dma_unmap_sg(host->dma.chan->device->dev,
841 				data->sg, data->sg_len,
842 				((data->flags & MMC_DATA_WRITE)
843 				 ? DMA_TO_DEVICE : DMA_FROM_DEVICE));
844 }
845 
846 /*
847  * This function is called by the DMA driver from tasklet context.
848  */
849 static void atmci_dma_complete(void *arg)
850 {
851 	struct atmel_mci	*host = arg;
852 	struct mmc_data		*data = host->data;
853 
854 	dev_vdbg(&host->pdev->dev, "DMA complete\n");
855 
856 	if (host->caps.has_dma_conf_reg)
857 		/* Disable DMA hardware handshaking on MCI */
858 		atmci_writel(host, ATMCI_DMA, atmci_readl(host, ATMCI_DMA) & ~ATMCI_DMAEN);
859 
860 	atmci_dma_cleanup(host);
861 
862 	/*
863 	 * If the card was removed, data will be NULL. No point trying
864 	 * to send the stop command or waiting for NBUSY in this case.
865 	 */
866 	if (data) {
867 		dev_dbg(&host->pdev->dev,
868 		        "(%s) set pending xfer complete\n", __func__);
869 		atmci_set_pending(host, EVENT_XFER_COMPLETE);
870 		tasklet_schedule(&host->tasklet);
871 
872 		/*
873 		 * Regardless of what the documentation says, we have
874 		 * to wait for NOTBUSY even after block read
875 		 * operations.
876 		 *
877 		 * When the DMA transfer is complete, the controller
878 		 * may still be reading the CRC from the card, i.e.
879 		 * the data transfer is still in progress and we
880 		 * haven't seen all the potential error bits yet.
881 		 *
882 		 * The interrupt handler will schedule a different
883 		 * tasklet to finish things up when the data transfer
884 		 * is completely done.
885 		 *
886 		 * We may not complete the mmc request here anyway
887 		 * because the mmc layer may call back and cause us to
888 		 * violate the "don't submit new operations from the
889 		 * completion callback" rule of the dma engine
890 		 * framework.
891 		 */
892 		atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
893 	}
894 }
895 
896 /*
897  * Returns a mask of interrupt flags to be enabled after the whole
898  * request has been prepared.
899  */
900 static u32 atmci_prepare_data(struct atmel_mci *host, struct mmc_data *data)
901 {
902 	u32 iflags;
903 
904 	data->error = -EINPROGRESS;
905 
906 	host->sg = data->sg;
907 	host->sg_len = data->sg_len;
908 	host->data = data;
909 	host->data_chan = NULL;
910 
911 	iflags = ATMCI_DATA_ERROR_FLAGS;
912 
913 	/*
914 	 * Errata: MMC data write operation with less than 12
915 	 * bytes is impossible.
916 	 *
917 	 * Errata: MCI Transmit Data Register (TDR) FIFO
918 	 * corruption when length is not multiple of 4.
919 	 */
920 	if (data->blocks * data->blksz < 12
921 			|| (data->blocks * data->blksz) & 3)
922 		host->need_reset = true;
923 
924 	host->pio_offset = 0;
925 	if (data->flags & MMC_DATA_READ)
926 		iflags |= ATMCI_RXRDY;
927 	else
928 		iflags |= ATMCI_TXRDY;
929 
930 	return iflags;
931 }
932 
933 /*
934  * Set interrupt flags and set block length into the MCI mode register even
935  * if this value is also accessible in the MCI block register. It seems to be
936  * necessary before the High Speed MCI version. It also map sg and configure
937  * PDC registers.
938  */
939 static u32
940 atmci_prepare_data_pdc(struct atmel_mci *host, struct mmc_data *data)
941 {
942 	u32 iflags, tmp;
943 	unsigned int sg_len;
944 	enum dma_data_direction dir;
945 	int i;
946 
947 	data->error = -EINPROGRESS;
948 
949 	host->data = data;
950 	host->sg = data->sg;
951 	iflags = ATMCI_DATA_ERROR_FLAGS;
952 
953 	/* Enable pdc mode */
954 	atmci_writel(host, ATMCI_MR, host->mode_reg | ATMCI_MR_PDCMODE);
955 
956 	if (data->flags & MMC_DATA_READ) {
957 		dir = DMA_FROM_DEVICE;
958 		iflags |= ATMCI_ENDRX | ATMCI_RXBUFF;
959 	} else {
960 		dir = DMA_TO_DEVICE;
961 		iflags |= ATMCI_ENDTX | ATMCI_TXBUFE | ATMCI_BLKE;
962 	}
963 
964 	/* Set BLKLEN */
965 	tmp = atmci_readl(host, ATMCI_MR);
966 	tmp &= 0x0000ffff;
967 	tmp |= ATMCI_BLKLEN(data->blksz);
968 	atmci_writel(host, ATMCI_MR, tmp);
969 
970 	/* Configure PDC */
971 	host->data_size = data->blocks * data->blksz;
972 	sg_len = dma_map_sg(&host->pdev->dev, data->sg, data->sg_len, dir);
973 
974 	if ((!host->caps.has_rwproof)
975 	    && (host->data->flags & MMC_DATA_WRITE)) {
976 		sg_copy_to_buffer(host->data->sg, host->data->sg_len,
977 		                  host->buffer, host->data_size);
978 		if (host->caps.has_bad_data_ordering)
979 			for (i = 0; i < host->data_size; i++)
980 				host->buffer[i] = swab32(host->buffer[i]);
981 	}
982 
983 	if (host->data_size)
984 		atmci_pdc_set_both_buf(host,
985 			((dir == DMA_FROM_DEVICE) ? XFER_RECEIVE : XFER_TRANSMIT));
986 
987 	return iflags;
988 }
989 
990 static u32
991 atmci_prepare_data_dma(struct atmel_mci *host, struct mmc_data *data)
992 {
993 	struct dma_chan			*chan;
994 	struct dma_async_tx_descriptor	*desc;
995 	struct scatterlist		*sg;
996 	unsigned int			i;
997 	enum dma_data_direction		direction;
998 	enum dma_transfer_direction	slave_dirn;
999 	unsigned int			sglen;
1000 	u32				maxburst;
1001 	u32 iflags;
1002 
1003 	data->error = -EINPROGRESS;
1004 
1005 	WARN_ON(host->data);
1006 	host->sg = NULL;
1007 	host->data = data;
1008 
1009 	iflags = ATMCI_DATA_ERROR_FLAGS;
1010 
1011 	/*
1012 	 * We don't do DMA on "complex" transfers, i.e. with
1013 	 * non-word-aligned buffers or lengths. Also, we don't bother
1014 	 * with all the DMA setup overhead for short transfers.
1015 	 */
1016 	if (data->blocks * data->blksz < ATMCI_DMA_THRESHOLD)
1017 		return atmci_prepare_data(host, data);
1018 	if (data->blksz & 3)
1019 		return atmci_prepare_data(host, data);
1020 
1021 	for_each_sg(data->sg, sg, data->sg_len, i) {
1022 		if (sg->offset & 3 || sg->length & 3)
1023 			return atmci_prepare_data(host, data);
1024 	}
1025 
1026 	/* If we don't have a channel, we can't do DMA */
1027 	chan = host->dma.chan;
1028 	if (chan)
1029 		host->data_chan = chan;
1030 
1031 	if (!chan)
1032 		return -ENODEV;
1033 
1034 	if (data->flags & MMC_DATA_READ) {
1035 		direction = DMA_FROM_DEVICE;
1036 		host->dma_conf.direction = slave_dirn = DMA_DEV_TO_MEM;
1037 		maxburst = atmci_convert_chksize(host->dma_conf.src_maxburst);
1038 	} else {
1039 		direction = DMA_TO_DEVICE;
1040 		host->dma_conf.direction = slave_dirn = DMA_MEM_TO_DEV;
1041 		maxburst = atmci_convert_chksize(host->dma_conf.dst_maxburst);
1042 	}
1043 
1044 	if (host->caps.has_dma_conf_reg)
1045 		atmci_writel(host, ATMCI_DMA, ATMCI_DMA_CHKSIZE(maxburst) |
1046 			ATMCI_DMAEN);
1047 
1048 	sglen = dma_map_sg(chan->device->dev, data->sg,
1049 			data->sg_len, direction);
1050 
1051 	dmaengine_slave_config(chan, &host->dma_conf);
1052 	desc = dmaengine_prep_slave_sg(chan,
1053 			data->sg, sglen, slave_dirn,
1054 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1055 	if (!desc)
1056 		goto unmap_exit;
1057 
1058 	host->dma.data_desc = desc;
1059 	desc->callback = atmci_dma_complete;
1060 	desc->callback_param = host;
1061 
1062 	return iflags;
1063 unmap_exit:
1064 	dma_unmap_sg(chan->device->dev, data->sg, data->sg_len, direction);
1065 	return -ENOMEM;
1066 }
1067 
1068 static void
1069 atmci_submit_data(struct atmel_mci *host, struct mmc_data *data)
1070 {
1071 	return;
1072 }
1073 
1074 /*
1075  * Start PDC according to transfer direction.
1076  */
1077 static void
1078 atmci_submit_data_pdc(struct atmel_mci *host, struct mmc_data *data)
1079 {
1080 	if (data->flags & MMC_DATA_READ)
1081 		atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTEN);
1082 	else
1083 		atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN);
1084 }
1085 
1086 static void
1087 atmci_submit_data_dma(struct atmel_mci *host, struct mmc_data *data)
1088 {
1089 	struct dma_chan			*chan = host->data_chan;
1090 	struct dma_async_tx_descriptor	*desc = host->dma.data_desc;
1091 
1092 	if (chan) {
1093 		dmaengine_submit(desc);
1094 		dma_async_issue_pending(chan);
1095 	}
1096 }
1097 
1098 static void atmci_stop_transfer(struct atmel_mci *host)
1099 {
1100 	dev_dbg(&host->pdev->dev,
1101 	        "(%s) set pending xfer complete\n", __func__);
1102 	atmci_set_pending(host, EVENT_XFER_COMPLETE);
1103 	atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1104 }
1105 
1106 /*
1107  * Stop data transfer because error(s) occurred.
1108  */
1109 static void atmci_stop_transfer_pdc(struct atmel_mci *host)
1110 {
1111 	atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
1112 }
1113 
1114 static void atmci_stop_transfer_dma(struct atmel_mci *host)
1115 {
1116 	struct dma_chan *chan = host->data_chan;
1117 
1118 	if (chan) {
1119 		dmaengine_terminate_all(chan);
1120 		atmci_dma_cleanup(host);
1121 	} else {
1122 		/* Data transfer was stopped by the interrupt handler */
1123 		dev_dbg(&host->pdev->dev,
1124 		        "(%s) set pending xfer complete\n", __func__);
1125 		atmci_set_pending(host, EVENT_XFER_COMPLETE);
1126 		atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1127 	}
1128 }
1129 
1130 /*
1131  * Start a request: prepare data if needed, prepare the command and activate
1132  * interrupts.
1133  */
1134 static void atmci_start_request(struct atmel_mci *host,
1135 		struct atmel_mci_slot *slot)
1136 {
1137 	struct mmc_request	*mrq;
1138 	struct mmc_command	*cmd;
1139 	struct mmc_data		*data;
1140 	u32			iflags;
1141 	u32			cmdflags;
1142 
1143 	mrq = slot->mrq;
1144 	host->cur_slot = slot;
1145 	host->mrq = mrq;
1146 
1147 	host->pending_events = 0;
1148 	host->completed_events = 0;
1149 	host->cmd_status = 0;
1150 	host->data_status = 0;
1151 
1152 	dev_dbg(&host->pdev->dev, "start request: cmd %u\n", mrq->cmd->opcode);
1153 
1154 	if (host->need_reset || host->caps.need_reset_after_xfer) {
1155 		iflags = atmci_readl(host, ATMCI_IMR);
1156 		iflags &= (ATMCI_SDIOIRQA | ATMCI_SDIOIRQB);
1157 		atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
1158 		atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
1159 		atmci_writel(host, ATMCI_MR, host->mode_reg);
1160 		if (host->caps.has_cfg_reg)
1161 			atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1162 		atmci_writel(host, ATMCI_IER, iflags);
1163 		host->need_reset = false;
1164 	}
1165 	atmci_writel(host, ATMCI_SDCR, slot->sdc_reg);
1166 
1167 	iflags = atmci_readl(host, ATMCI_IMR);
1168 	if (iflags & ~(ATMCI_SDIOIRQA | ATMCI_SDIOIRQB))
1169 		dev_dbg(&slot->mmc->class_dev, "WARNING: IMR=0x%08x\n",
1170 				iflags);
1171 
1172 	if (unlikely(test_and_clear_bit(ATMCI_CARD_NEED_INIT, &slot->flags))) {
1173 		/* Send init sequence (74 clock cycles) */
1174 		atmci_writel(host, ATMCI_CMDR, ATMCI_CMDR_SPCMD_INIT);
1175 		while (!(atmci_readl(host, ATMCI_SR) & ATMCI_CMDRDY))
1176 			cpu_relax();
1177 	}
1178 	iflags = 0;
1179 	data = mrq->data;
1180 	if (data) {
1181 		atmci_set_timeout(host, slot, data);
1182 
1183 		/* Must set block count/size before sending command */
1184 		atmci_writel(host, ATMCI_BLKR, ATMCI_BCNT(data->blocks)
1185 				| ATMCI_BLKLEN(data->blksz));
1186 		dev_vdbg(&slot->mmc->class_dev, "BLKR=0x%08x\n",
1187 			ATMCI_BCNT(data->blocks) | ATMCI_BLKLEN(data->blksz));
1188 
1189 		iflags |= host->prepare_data(host, data);
1190 	}
1191 
1192 	iflags |= ATMCI_CMDRDY;
1193 	cmd = mrq->cmd;
1194 	cmdflags = atmci_prepare_command(slot->mmc, cmd);
1195 	atmci_send_command(host, cmd, cmdflags);
1196 
1197 	if (data)
1198 		host->submit_data(host, data);
1199 
1200 	if (mrq->stop) {
1201 		host->stop_cmdr = atmci_prepare_command(slot->mmc, mrq->stop);
1202 		host->stop_cmdr |= ATMCI_CMDR_STOP_XFER;
1203 		if (!(data->flags & MMC_DATA_WRITE))
1204 			host->stop_cmdr |= ATMCI_CMDR_TRDIR_READ;
1205 		if (data->flags & MMC_DATA_STREAM)
1206 			host->stop_cmdr |= ATMCI_CMDR_STREAM;
1207 		else
1208 			host->stop_cmdr |= ATMCI_CMDR_MULTI_BLOCK;
1209 	}
1210 
1211 	/*
1212 	 * We could have enabled interrupts earlier, but I suspect
1213 	 * that would open up a nice can of interesting race
1214 	 * conditions (e.g. command and data complete, but stop not
1215 	 * prepared yet.)
1216 	 */
1217 	atmci_writel(host, ATMCI_IER, iflags);
1218 
1219 	mod_timer(&host->timer, jiffies +  msecs_to_jiffies(2000));
1220 }
1221 
1222 static void atmci_queue_request(struct atmel_mci *host,
1223 		struct atmel_mci_slot *slot, struct mmc_request *mrq)
1224 {
1225 	dev_vdbg(&slot->mmc->class_dev, "queue request: state=%d\n",
1226 			host->state);
1227 
1228 	spin_lock_bh(&host->lock);
1229 	slot->mrq = mrq;
1230 	if (host->state == STATE_IDLE) {
1231 		host->state = STATE_SENDING_CMD;
1232 		atmci_start_request(host, slot);
1233 	} else {
1234 		dev_dbg(&host->pdev->dev, "queue request\n");
1235 		list_add_tail(&slot->queue_node, &host->queue);
1236 	}
1237 	spin_unlock_bh(&host->lock);
1238 }
1239 
1240 static void atmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
1241 {
1242 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1243 	struct atmel_mci	*host = slot->host;
1244 	struct mmc_data		*data;
1245 
1246 	WARN_ON(slot->mrq);
1247 	dev_dbg(&host->pdev->dev, "MRQ: cmd %u\n", mrq->cmd->opcode);
1248 
1249 	/*
1250 	 * We may "know" the card is gone even though there's still an
1251 	 * electrical connection. If so, we really need to communicate
1252 	 * this to the MMC core since there won't be any more
1253 	 * interrupts as the card is completely removed. Otherwise,
1254 	 * the MMC core might believe the card is still there even
1255 	 * though the card was just removed very slowly.
1256 	 */
1257 	if (!test_bit(ATMCI_CARD_PRESENT, &slot->flags)) {
1258 		mrq->cmd->error = -ENOMEDIUM;
1259 		mmc_request_done(mmc, mrq);
1260 		return;
1261 	}
1262 
1263 	/* We don't support multiple blocks of weird lengths. */
1264 	data = mrq->data;
1265 	if (data && data->blocks > 1 && data->blksz & 3) {
1266 		mrq->cmd->error = -EINVAL;
1267 		mmc_request_done(mmc, mrq);
1268 	}
1269 
1270 	atmci_queue_request(host, slot, mrq);
1271 }
1272 
1273 static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
1274 {
1275 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1276 	struct atmel_mci	*host = slot->host;
1277 	unsigned int		i;
1278 	bool			unprepare_clk;
1279 
1280 	slot->sdc_reg &= ~ATMCI_SDCBUS_MASK;
1281 	switch (ios->bus_width) {
1282 	case MMC_BUS_WIDTH_1:
1283 		slot->sdc_reg |= ATMCI_SDCBUS_1BIT;
1284 		break;
1285 	case MMC_BUS_WIDTH_4:
1286 		slot->sdc_reg |= ATMCI_SDCBUS_4BIT;
1287 		break;
1288 	}
1289 
1290 	if (ios->clock) {
1291 		unsigned int clock_min = ~0U;
1292 		u32 clkdiv;
1293 
1294 		clk_prepare(host->mck);
1295 		unprepare_clk = true;
1296 
1297 		spin_lock_bh(&host->lock);
1298 		if (!host->mode_reg) {
1299 			clk_enable(host->mck);
1300 			unprepare_clk = false;
1301 			atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
1302 			atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
1303 			if (host->caps.has_cfg_reg)
1304 				atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1305 		}
1306 
1307 		/*
1308 		 * Use mirror of ios->clock to prevent race with mmc
1309 		 * core ios update when finding the minimum.
1310 		 */
1311 		slot->clock = ios->clock;
1312 		for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
1313 			if (host->slot[i] && host->slot[i]->clock
1314 					&& host->slot[i]->clock < clock_min)
1315 				clock_min = host->slot[i]->clock;
1316 		}
1317 
1318 		/* Calculate clock divider */
1319 		if (host->caps.has_odd_clk_div) {
1320 			clkdiv = DIV_ROUND_UP(host->bus_hz, clock_min) - 2;
1321 			if (clkdiv > 511) {
1322 				dev_warn(&mmc->class_dev,
1323 				         "clock %u too slow; using %lu\n",
1324 				         clock_min, host->bus_hz / (511 + 2));
1325 				clkdiv = 511;
1326 			}
1327 			host->mode_reg = ATMCI_MR_CLKDIV(clkdiv >> 1)
1328 			                 | ATMCI_MR_CLKODD(clkdiv & 1);
1329 		} else {
1330 			clkdiv = DIV_ROUND_UP(host->bus_hz, 2 * clock_min) - 1;
1331 			if (clkdiv > 255) {
1332 				dev_warn(&mmc->class_dev,
1333 				         "clock %u too slow; using %lu\n",
1334 				         clock_min, host->bus_hz / (2 * 256));
1335 				clkdiv = 255;
1336 			}
1337 			host->mode_reg = ATMCI_MR_CLKDIV(clkdiv);
1338 		}
1339 
1340 		/*
1341 		 * WRPROOF and RDPROOF prevent overruns/underruns by
1342 		 * stopping the clock when the FIFO is full/empty.
1343 		 * This state is not expected to last for long.
1344 		 */
1345 		if (host->caps.has_rwproof)
1346 			host->mode_reg |= (ATMCI_MR_WRPROOF | ATMCI_MR_RDPROOF);
1347 
1348 		if (host->caps.has_cfg_reg) {
1349 			/* setup High Speed mode in relation with card capacity */
1350 			if (ios->timing == MMC_TIMING_SD_HS)
1351 				host->cfg_reg |= ATMCI_CFG_HSMODE;
1352 			else
1353 				host->cfg_reg &= ~ATMCI_CFG_HSMODE;
1354 		}
1355 
1356 		if (list_empty(&host->queue)) {
1357 			atmci_writel(host, ATMCI_MR, host->mode_reg);
1358 			if (host->caps.has_cfg_reg)
1359 				atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1360 		} else {
1361 			host->need_clock_update = true;
1362 		}
1363 
1364 		spin_unlock_bh(&host->lock);
1365 	} else {
1366 		bool any_slot_active = false;
1367 
1368 		unprepare_clk = false;
1369 
1370 		spin_lock_bh(&host->lock);
1371 		slot->clock = 0;
1372 		for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
1373 			if (host->slot[i] && host->slot[i]->clock) {
1374 				any_slot_active = true;
1375 				break;
1376 			}
1377 		}
1378 		if (!any_slot_active) {
1379 			atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIDIS);
1380 			if (host->mode_reg) {
1381 				atmci_readl(host, ATMCI_MR);
1382 				clk_disable(host->mck);
1383 				unprepare_clk = true;
1384 			}
1385 			host->mode_reg = 0;
1386 		}
1387 		spin_unlock_bh(&host->lock);
1388 	}
1389 
1390 	if (unprepare_clk)
1391 		clk_unprepare(host->mck);
1392 
1393 	switch (ios->power_mode) {
1394 	case MMC_POWER_UP:
1395 		set_bit(ATMCI_CARD_NEED_INIT, &slot->flags);
1396 		break;
1397 	default:
1398 		/*
1399 		 * TODO: None of the currently available AVR32-based
1400 		 * boards allow MMC power to be turned off. Implement
1401 		 * power control when this can be tested properly.
1402 		 *
1403 		 * We also need to hook this into the clock management
1404 		 * somehow so that newly inserted cards aren't
1405 		 * subjected to a fast clock before we have a chance
1406 		 * to figure out what the maximum rate is. Currently,
1407 		 * there's no way to avoid this, and there never will
1408 		 * be for boards that don't support power control.
1409 		 */
1410 		break;
1411 	}
1412 }
1413 
1414 static int atmci_get_ro(struct mmc_host *mmc)
1415 {
1416 	int			read_only = -ENOSYS;
1417 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1418 
1419 	if (gpio_is_valid(slot->wp_pin)) {
1420 		read_only = gpio_get_value(slot->wp_pin);
1421 		dev_dbg(&mmc->class_dev, "card is %s\n",
1422 				read_only ? "read-only" : "read-write");
1423 	}
1424 
1425 	return read_only;
1426 }
1427 
1428 static int atmci_get_cd(struct mmc_host *mmc)
1429 {
1430 	int			present = -ENOSYS;
1431 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1432 
1433 	if (gpio_is_valid(slot->detect_pin)) {
1434 		present = !(gpio_get_value(slot->detect_pin) ^
1435 			    slot->detect_is_active_high);
1436 		dev_dbg(&mmc->class_dev, "card is %spresent\n",
1437 				present ? "" : "not ");
1438 	}
1439 
1440 	return present;
1441 }
1442 
1443 static void atmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
1444 {
1445 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1446 	struct atmel_mci	*host = slot->host;
1447 
1448 	if (enable)
1449 		atmci_writel(host, ATMCI_IER, slot->sdio_irq);
1450 	else
1451 		atmci_writel(host, ATMCI_IDR, slot->sdio_irq);
1452 }
1453 
1454 static const struct mmc_host_ops atmci_ops = {
1455 	.request	= atmci_request,
1456 	.set_ios	= atmci_set_ios,
1457 	.get_ro		= atmci_get_ro,
1458 	.get_cd		= atmci_get_cd,
1459 	.enable_sdio_irq = atmci_enable_sdio_irq,
1460 };
1461 
1462 /* Called with host->lock held */
1463 static void atmci_request_end(struct atmel_mci *host, struct mmc_request *mrq)
1464 	__releases(&host->lock)
1465 	__acquires(&host->lock)
1466 {
1467 	struct atmel_mci_slot	*slot = NULL;
1468 	struct mmc_host		*prev_mmc = host->cur_slot->mmc;
1469 
1470 	WARN_ON(host->cmd || host->data);
1471 
1472 	/*
1473 	 * Update the MMC clock rate if necessary. This may be
1474 	 * necessary if set_ios() is called when a different slot is
1475 	 * busy transferring data.
1476 	 */
1477 	if (host->need_clock_update) {
1478 		atmci_writel(host, ATMCI_MR, host->mode_reg);
1479 		if (host->caps.has_cfg_reg)
1480 			atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1481 	}
1482 
1483 	host->cur_slot->mrq = NULL;
1484 	host->mrq = NULL;
1485 	if (!list_empty(&host->queue)) {
1486 		slot = list_entry(host->queue.next,
1487 				struct atmel_mci_slot, queue_node);
1488 		list_del(&slot->queue_node);
1489 		dev_vdbg(&host->pdev->dev, "list not empty: %s is next\n",
1490 				mmc_hostname(slot->mmc));
1491 		host->state = STATE_SENDING_CMD;
1492 		atmci_start_request(host, slot);
1493 	} else {
1494 		dev_vdbg(&host->pdev->dev, "list empty\n");
1495 		host->state = STATE_IDLE;
1496 	}
1497 
1498 	del_timer(&host->timer);
1499 
1500 	spin_unlock(&host->lock);
1501 	mmc_request_done(prev_mmc, mrq);
1502 	spin_lock(&host->lock);
1503 }
1504 
1505 static void atmci_command_complete(struct atmel_mci *host,
1506 			struct mmc_command *cmd)
1507 {
1508 	u32		status = host->cmd_status;
1509 
1510 	/* Read the response from the card (up to 16 bytes) */
1511 	cmd->resp[0] = atmci_readl(host, ATMCI_RSPR);
1512 	cmd->resp[1] = atmci_readl(host, ATMCI_RSPR);
1513 	cmd->resp[2] = atmci_readl(host, ATMCI_RSPR);
1514 	cmd->resp[3] = atmci_readl(host, ATMCI_RSPR);
1515 
1516 	if (status & ATMCI_RTOE)
1517 		cmd->error = -ETIMEDOUT;
1518 	else if ((cmd->flags & MMC_RSP_CRC) && (status & ATMCI_RCRCE))
1519 		cmd->error = -EILSEQ;
1520 	else if (status & (ATMCI_RINDE | ATMCI_RDIRE | ATMCI_RENDE))
1521 		cmd->error = -EIO;
1522 	else if (host->mrq->data && (host->mrq->data->blksz & 3)) {
1523 		if (host->caps.need_blksz_mul_4) {
1524 			cmd->error = -EINVAL;
1525 			host->need_reset = 1;
1526 		}
1527 	} else
1528 		cmd->error = 0;
1529 }
1530 
1531 static void atmci_detect_change(unsigned long data)
1532 {
1533 	struct atmel_mci_slot	*slot = (struct atmel_mci_slot *)data;
1534 	bool			present;
1535 	bool			present_old;
1536 
1537 	/*
1538 	 * atmci_cleanup_slot() sets the ATMCI_SHUTDOWN flag before
1539 	 * freeing the interrupt. We must not re-enable the interrupt
1540 	 * if it has been freed, and if we're shutting down, it
1541 	 * doesn't really matter whether the card is present or not.
1542 	 */
1543 	smp_rmb();
1544 	if (test_bit(ATMCI_SHUTDOWN, &slot->flags))
1545 		return;
1546 
1547 	enable_irq(gpio_to_irq(slot->detect_pin));
1548 	present = !(gpio_get_value(slot->detect_pin) ^
1549 		    slot->detect_is_active_high);
1550 	present_old = test_bit(ATMCI_CARD_PRESENT, &slot->flags);
1551 
1552 	dev_vdbg(&slot->mmc->class_dev, "detect change: %d (was %d)\n",
1553 			present, present_old);
1554 
1555 	if (present != present_old) {
1556 		struct atmel_mci	*host = slot->host;
1557 		struct mmc_request	*mrq;
1558 
1559 		dev_dbg(&slot->mmc->class_dev, "card %s\n",
1560 			present ? "inserted" : "removed");
1561 
1562 		spin_lock(&host->lock);
1563 
1564 		if (!present)
1565 			clear_bit(ATMCI_CARD_PRESENT, &slot->flags);
1566 		else
1567 			set_bit(ATMCI_CARD_PRESENT, &slot->flags);
1568 
1569 		/* Clean up queue if present */
1570 		mrq = slot->mrq;
1571 		if (mrq) {
1572 			if (mrq == host->mrq) {
1573 				/*
1574 				 * Reset controller to terminate any ongoing
1575 				 * commands or data transfers.
1576 				 */
1577 				atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
1578 				atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
1579 				atmci_writel(host, ATMCI_MR, host->mode_reg);
1580 				if (host->caps.has_cfg_reg)
1581 					atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1582 
1583 				host->data = NULL;
1584 				host->cmd = NULL;
1585 
1586 				switch (host->state) {
1587 				case STATE_IDLE:
1588 					break;
1589 				case STATE_SENDING_CMD:
1590 					mrq->cmd->error = -ENOMEDIUM;
1591 					if (mrq->data)
1592 						host->stop_transfer(host);
1593 					break;
1594 				case STATE_DATA_XFER:
1595 					mrq->data->error = -ENOMEDIUM;
1596 					host->stop_transfer(host);
1597 					break;
1598 				case STATE_WAITING_NOTBUSY:
1599 					mrq->data->error = -ENOMEDIUM;
1600 					break;
1601 				case STATE_SENDING_STOP:
1602 					mrq->stop->error = -ENOMEDIUM;
1603 					break;
1604 				case STATE_END_REQUEST:
1605 					break;
1606 				}
1607 
1608 				atmci_request_end(host, mrq);
1609 			} else {
1610 				list_del(&slot->queue_node);
1611 				mrq->cmd->error = -ENOMEDIUM;
1612 				if (mrq->data)
1613 					mrq->data->error = -ENOMEDIUM;
1614 				if (mrq->stop)
1615 					mrq->stop->error = -ENOMEDIUM;
1616 
1617 				spin_unlock(&host->lock);
1618 				mmc_request_done(slot->mmc, mrq);
1619 				spin_lock(&host->lock);
1620 			}
1621 		}
1622 		spin_unlock(&host->lock);
1623 
1624 		mmc_detect_change(slot->mmc, 0);
1625 	}
1626 }
1627 
1628 static void atmci_tasklet_func(unsigned long priv)
1629 {
1630 	struct atmel_mci	*host = (struct atmel_mci *)priv;
1631 	struct mmc_request	*mrq = host->mrq;
1632 	struct mmc_data		*data = host->data;
1633 	enum atmel_mci_state	state = host->state;
1634 	enum atmel_mci_state	prev_state;
1635 	u32			status;
1636 
1637 	spin_lock(&host->lock);
1638 
1639 	state = host->state;
1640 
1641 	dev_vdbg(&host->pdev->dev,
1642 		"tasklet: state %u pending/completed/mask %lx/%lx/%x\n",
1643 		state, host->pending_events, host->completed_events,
1644 		atmci_readl(host, ATMCI_IMR));
1645 
1646 	do {
1647 		prev_state = state;
1648 		dev_dbg(&host->pdev->dev, "FSM: state=%d\n", state);
1649 
1650 		switch (state) {
1651 		case STATE_IDLE:
1652 			break;
1653 
1654 		case STATE_SENDING_CMD:
1655 			/*
1656 			 * Command has been sent, we are waiting for command
1657 			 * ready. Then we have three next states possible:
1658 			 * END_REQUEST by default, WAITING_NOTBUSY if it's a
1659 			 * command needing it or DATA_XFER if there is data.
1660 			 */
1661 			dev_dbg(&host->pdev->dev, "FSM: cmd ready?\n");
1662 			if (!atmci_test_and_clear_pending(host,
1663 						EVENT_CMD_RDY))
1664 				break;
1665 
1666 			dev_dbg(&host->pdev->dev, "set completed cmd ready\n");
1667 			host->cmd = NULL;
1668 			atmci_set_completed(host, EVENT_CMD_RDY);
1669 			atmci_command_complete(host, mrq->cmd);
1670 			if (mrq->data) {
1671 				dev_dbg(&host->pdev->dev,
1672 				        "command with data transfer");
1673 				/*
1674 				 * If there is a command error don't start
1675 				 * data transfer.
1676 				 */
1677 				if (mrq->cmd->error) {
1678 					host->stop_transfer(host);
1679 					host->data = NULL;
1680 					atmci_writel(host, ATMCI_IDR,
1681 					             ATMCI_TXRDY | ATMCI_RXRDY
1682 					             | ATMCI_DATA_ERROR_FLAGS);
1683 					state = STATE_END_REQUEST;
1684 				} else
1685 					state = STATE_DATA_XFER;
1686 			} else if ((!mrq->data) && (mrq->cmd->flags & MMC_RSP_BUSY)) {
1687 				dev_dbg(&host->pdev->dev,
1688 				        "command response need waiting notbusy");
1689 				atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1690 				state = STATE_WAITING_NOTBUSY;
1691 			} else
1692 				state = STATE_END_REQUEST;
1693 
1694 			break;
1695 
1696 		case STATE_DATA_XFER:
1697 			if (atmci_test_and_clear_pending(host,
1698 						EVENT_DATA_ERROR)) {
1699 				dev_dbg(&host->pdev->dev, "set completed data error\n");
1700 				atmci_set_completed(host, EVENT_DATA_ERROR);
1701 				state = STATE_END_REQUEST;
1702 				break;
1703 			}
1704 
1705 			/*
1706 			 * A data transfer is in progress. The event expected
1707 			 * to move to the next state depends of data transfer
1708 			 * type (PDC or DMA). Once transfer done we can move
1709 			 * to the next step which is WAITING_NOTBUSY in write
1710 			 * case and directly SENDING_STOP in read case.
1711 			 */
1712 			dev_dbg(&host->pdev->dev, "FSM: xfer complete?\n");
1713 			if (!atmci_test_and_clear_pending(host,
1714 						EVENT_XFER_COMPLETE))
1715 				break;
1716 
1717 			dev_dbg(&host->pdev->dev,
1718 			        "(%s) set completed xfer complete\n",
1719 				__func__);
1720 			atmci_set_completed(host, EVENT_XFER_COMPLETE);
1721 
1722 			if (host->caps.need_notbusy_for_read_ops ||
1723 			   (host->data->flags & MMC_DATA_WRITE)) {
1724 				atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1725 				state = STATE_WAITING_NOTBUSY;
1726 			} else if (host->mrq->stop) {
1727 				atmci_writel(host, ATMCI_IER, ATMCI_CMDRDY);
1728 				atmci_send_stop_cmd(host, data);
1729 				state = STATE_SENDING_STOP;
1730 			} else {
1731 				host->data = NULL;
1732 				data->bytes_xfered = data->blocks * data->blksz;
1733 				data->error = 0;
1734 				state = STATE_END_REQUEST;
1735 			}
1736 			break;
1737 
1738 		case STATE_WAITING_NOTBUSY:
1739 			/*
1740 			 * We can be in the state for two reasons: a command
1741 			 * requiring waiting not busy signal (stop command
1742 			 * included) or a write operation. In the latest case,
1743 			 * we need to send a stop command.
1744 			 */
1745 			dev_dbg(&host->pdev->dev, "FSM: not busy?\n");
1746 			if (!atmci_test_and_clear_pending(host,
1747 						EVENT_NOTBUSY))
1748 				break;
1749 
1750 			dev_dbg(&host->pdev->dev, "set completed not busy\n");
1751 			atmci_set_completed(host, EVENT_NOTBUSY);
1752 
1753 			if (host->data) {
1754 				/*
1755 				 * For some commands such as CMD53, even if
1756 				 * there is data transfer, there is no stop
1757 				 * command to send.
1758 				 */
1759 				if (host->mrq->stop) {
1760 					atmci_writel(host, ATMCI_IER,
1761 					             ATMCI_CMDRDY);
1762 					atmci_send_stop_cmd(host, data);
1763 					state = STATE_SENDING_STOP;
1764 				} else {
1765 					host->data = NULL;
1766 					data->bytes_xfered = data->blocks
1767 					                     * data->blksz;
1768 					data->error = 0;
1769 					state = STATE_END_REQUEST;
1770 				}
1771 			} else
1772 				state = STATE_END_REQUEST;
1773 			break;
1774 
1775 		case STATE_SENDING_STOP:
1776 			/*
1777 			 * In this state, it is important to set host->data to
1778 			 * NULL (which is tested in the waiting notbusy state)
1779 			 * in order to go to the end request state instead of
1780 			 * sending stop again.
1781 			 */
1782 			dev_dbg(&host->pdev->dev, "FSM: cmd ready?\n");
1783 			if (!atmci_test_and_clear_pending(host,
1784 						EVENT_CMD_RDY))
1785 				break;
1786 
1787 			dev_dbg(&host->pdev->dev, "FSM: cmd ready\n");
1788 			host->cmd = NULL;
1789 			data->bytes_xfered = data->blocks * data->blksz;
1790 			data->error = 0;
1791 			atmci_command_complete(host, mrq->stop);
1792 			if (mrq->stop->error) {
1793 				host->stop_transfer(host);
1794 				atmci_writel(host, ATMCI_IDR,
1795 				             ATMCI_TXRDY | ATMCI_RXRDY
1796 				             | ATMCI_DATA_ERROR_FLAGS);
1797 				state = STATE_END_REQUEST;
1798 			} else {
1799 				atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1800 				state = STATE_WAITING_NOTBUSY;
1801 			}
1802 			host->data = NULL;
1803 			break;
1804 
1805 		case STATE_END_REQUEST:
1806 			atmci_writel(host, ATMCI_IDR, ATMCI_TXRDY | ATMCI_RXRDY
1807 			                   | ATMCI_DATA_ERROR_FLAGS);
1808 			status = host->data_status;
1809 			if (unlikely(status)) {
1810 				host->stop_transfer(host);
1811 				host->data = NULL;
1812 				if (data) {
1813 					if (status & ATMCI_DTOE) {
1814 						data->error = -ETIMEDOUT;
1815 					} else if (status & ATMCI_DCRCE) {
1816 						data->error = -EILSEQ;
1817 					} else {
1818 						data->error = -EIO;
1819 					}
1820 				}
1821 			}
1822 
1823 			atmci_request_end(host, host->mrq);
1824 			state = STATE_IDLE;
1825 			break;
1826 		}
1827 	} while (state != prev_state);
1828 
1829 	host->state = state;
1830 
1831 	spin_unlock(&host->lock);
1832 }
1833 
1834 static void atmci_read_data_pio(struct atmel_mci *host)
1835 {
1836 	struct scatterlist	*sg = host->sg;
1837 	void			*buf = sg_virt(sg);
1838 	unsigned int		offset = host->pio_offset;
1839 	struct mmc_data		*data = host->data;
1840 	u32			value;
1841 	u32			status;
1842 	unsigned int		nbytes = 0;
1843 
1844 	do {
1845 		value = atmci_readl(host, ATMCI_RDR);
1846 		if (likely(offset + 4 <= sg->length)) {
1847 			put_unaligned(value, (u32 *)(buf + offset));
1848 
1849 			offset += 4;
1850 			nbytes += 4;
1851 
1852 			if (offset == sg->length) {
1853 				flush_dcache_page(sg_page(sg));
1854 				host->sg = sg = sg_next(sg);
1855 				host->sg_len--;
1856 				if (!sg || !host->sg_len)
1857 					goto done;
1858 
1859 				offset = 0;
1860 				buf = sg_virt(sg);
1861 			}
1862 		} else {
1863 			unsigned int remaining = sg->length - offset;
1864 			memcpy(buf + offset, &value, remaining);
1865 			nbytes += remaining;
1866 
1867 			flush_dcache_page(sg_page(sg));
1868 			host->sg = sg = sg_next(sg);
1869 			host->sg_len--;
1870 			if (!sg || !host->sg_len)
1871 				goto done;
1872 
1873 			offset = 4 - remaining;
1874 			buf = sg_virt(sg);
1875 			memcpy(buf, (u8 *)&value + remaining, offset);
1876 			nbytes += offset;
1877 		}
1878 
1879 		status = atmci_readl(host, ATMCI_SR);
1880 		if (status & ATMCI_DATA_ERROR_FLAGS) {
1881 			atmci_writel(host, ATMCI_IDR, (ATMCI_NOTBUSY | ATMCI_RXRDY
1882 						| ATMCI_DATA_ERROR_FLAGS));
1883 			host->data_status = status;
1884 			data->bytes_xfered += nbytes;
1885 			return;
1886 		}
1887 	} while (status & ATMCI_RXRDY);
1888 
1889 	host->pio_offset = offset;
1890 	data->bytes_xfered += nbytes;
1891 
1892 	return;
1893 
1894 done:
1895 	atmci_writel(host, ATMCI_IDR, ATMCI_RXRDY);
1896 	atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1897 	data->bytes_xfered += nbytes;
1898 	smp_wmb();
1899 	atmci_set_pending(host, EVENT_XFER_COMPLETE);
1900 }
1901 
1902 static void atmci_write_data_pio(struct atmel_mci *host)
1903 {
1904 	struct scatterlist	*sg = host->sg;
1905 	void			*buf = sg_virt(sg);
1906 	unsigned int		offset = host->pio_offset;
1907 	struct mmc_data		*data = host->data;
1908 	u32			value;
1909 	u32			status;
1910 	unsigned int		nbytes = 0;
1911 
1912 	do {
1913 		if (likely(offset + 4 <= sg->length)) {
1914 			value = get_unaligned((u32 *)(buf + offset));
1915 			atmci_writel(host, ATMCI_TDR, value);
1916 
1917 			offset += 4;
1918 			nbytes += 4;
1919 			if (offset == sg->length) {
1920 				host->sg = sg = sg_next(sg);
1921 				host->sg_len--;
1922 				if (!sg || !host->sg_len)
1923 					goto done;
1924 
1925 				offset = 0;
1926 				buf = sg_virt(sg);
1927 			}
1928 		} else {
1929 			unsigned int remaining = sg->length - offset;
1930 
1931 			value = 0;
1932 			memcpy(&value, buf + offset, remaining);
1933 			nbytes += remaining;
1934 
1935 			host->sg = sg = sg_next(sg);
1936 			host->sg_len--;
1937 			if (!sg || !host->sg_len) {
1938 				atmci_writel(host, ATMCI_TDR, value);
1939 				goto done;
1940 			}
1941 
1942 			offset = 4 - remaining;
1943 			buf = sg_virt(sg);
1944 			memcpy((u8 *)&value + remaining, buf, offset);
1945 			atmci_writel(host, ATMCI_TDR, value);
1946 			nbytes += offset;
1947 		}
1948 
1949 		status = atmci_readl(host, ATMCI_SR);
1950 		if (status & ATMCI_DATA_ERROR_FLAGS) {
1951 			atmci_writel(host, ATMCI_IDR, (ATMCI_NOTBUSY | ATMCI_TXRDY
1952 						| ATMCI_DATA_ERROR_FLAGS));
1953 			host->data_status = status;
1954 			data->bytes_xfered += nbytes;
1955 			return;
1956 		}
1957 	} while (status & ATMCI_TXRDY);
1958 
1959 	host->pio_offset = offset;
1960 	data->bytes_xfered += nbytes;
1961 
1962 	return;
1963 
1964 done:
1965 	atmci_writel(host, ATMCI_IDR, ATMCI_TXRDY);
1966 	atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1967 	data->bytes_xfered += nbytes;
1968 	smp_wmb();
1969 	atmci_set_pending(host, EVENT_XFER_COMPLETE);
1970 }
1971 
1972 static void atmci_sdio_interrupt(struct atmel_mci *host, u32 status)
1973 {
1974 	int	i;
1975 
1976 	for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
1977 		struct atmel_mci_slot *slot = host->slot[i];
1978 		if (slot && (status & slot->sdio_irq)) {
1979 			mmc_signal_sdio_irq(slot->mmc);
1980 		}
1981 	}
1982 }
1983 
1984 
1985 static irqreturn_t atmci_interrupt(int irq, void *dev_id)
1986 {
1987 	struct atmel_mci	*host = dev_id;
1988 	u32			status, mask, pending;
1989 	unsigned int		pass_count = 0;
1990 
1991 	do {
1992 		status = atmci_readl(host, ATMCI_SR);
1993 		mask = atmci_readl(host, ATMCI_IMR);
1994 		pending = status & mask;
1995 		if (!pending)
1996 			break;
1997 
1998 		if (pending & ATMCI_DATA_ERROR_FLAGS) {
1999 			dev_dbg(&host->pdev->dev, "IRQ: data error\n");
2000 			atmci_writel(host, ATMCI_IDR, ATMCI_DATA_ERROR_FLAGS
2001 					| ATMCI_RXRDY | ATMCI_TXRDY
2002 					| ATMCI_ENDRX | ATMCI_ENDTX
2003 					| ATMCI_RXBUFF | ATMCI_TXBUFE);
2004 
2005 			host->data_status = status;
2006 			dev_dbg(&host->pdev->dev, "set pending data error\n");
2007 			smp_wmb();
2008 			atmci_set_pending(host, EVENT_DATA_ERROR);
2009 			tasklet_schedule(&host->tasklet);
2010 		}
2011 
2012 		if (pending & ATMCI_TXBUFE) {
2013 			dev_dbg(&host->pdev->dev, "IRQ: tx buffer empty\n");
2014 			atmci_writel(host, ATMCI_IDR, ATMCI_TXBUFE);
2015 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDTX);
2016 			/*
2017 			 * We can receive this interruption before having configured
2018 			 * the second pdc buffer, so we need to reconfigure first and
2019 			 * second buffers again
2020 			 */
2021 			if (host->data_size) {
2022 				atmci_pdc_set_both_buf(host, XFER_TRANSMIT);
2023 				atmci_writel(host, ATMCI_IER, ATMCI_ENDTX);
2024 				atmci_writel(host, ATMCI_IER, ATMCI_TXBUFE);
2025 			} else {
2026 				atmci_pdc_complete(host);
2027 			}
2028 		} else if (pending & ATMCI_ENDTX) {
2029 			dev_dbg(&host->pdev->dev, "IRQ: end of tx buffer\n");
2030 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDTX);
2031 
2032 			if (host->data_size) {
2033 				atmci_pdc_set_single_buf(host,
2034 						XFER_TRANSMIT, PDC_SECOND_BUF);
2035 				atmci_writel(host, ATMCI_IER, ATMCI_ENDTX);
2036 			}
2037 		}
2038 
2039 		if (pending & ATMCI_RXBUFF) {
2040 			dev_dbg(&host->pdev->dev, "IRQ: rx buffer full\n");
2041 			atmci_writel(host, ATMCI_IDR, ATMCI_RXBUFF);
2042 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDRX);
2043 			/*
2044 			 * We can receive this interruption before having configured
2045 			 * the second pdc buffer, so we need to reconfigure first and
2046 			 * second buffers again
2047 			 */
2048 			if (host->data_size) {
2049 				atmci_pdc_set_both_buf(host, XFER_RECEIVE);
2050 				atmci_writel(host, ATMCI_IER, ATMCI_ENDRX);
2051 				atmci_writel(host, ATMCI_IER, ATMCI_RXBUFF);
2052 			} else {
2053 				atmci_pdc_complete(host);
2054 			}
2055 		} else if (pending & ATMCI_ENDRX) {
2056 			dev_dbg(&host->pdev->dev, "IRQ: end of rx buffer\n");
2057 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDRX);
2058 
2059 			if (host->data_size) {
2060 				atmci_pdc_set_single_buf(host,
2061 						XFER_RECEIVE, PDC_SECOND_BUF);
2062 				atmci_writel(host, ATMCI_IER, ATMCI_ENDRX);
2063 			}
2064 		}
2065 
2066 		/*
2067 		 * First mci IPs, so mainly the ones having pdc, have some
2068 		 * issues with the notbusy signal. You can't get it after
2069 		 * data transmission if you have not sent a stop command.
2070 		 * The appropriate workaround is to use the BLKE signal.
2071 		 */
2072 		if (pending & ATMCI_BLKE) {
2073 			dev_dbg(&host->pdev->dev, "IRQ: blke\n");
2074 			atmci_writel(host, ATMCI_IDR, ATMCI_BLKE);
2075 			smp_wmb();
2076 			dev_dbg(&host->pdev->dev, "set pending notbusy\n");
2077 			atmci_set_pending(host, EVENT_NOTBUSY);
2078 			tasklet_schedule(&host->tasklet);
2079 		}
2080 
2081 		if (pending & ATMCI_NOTBUSY) {
2082 			dev_dbg(&host->pdev->dev, "IRQ: not_busy\n");
2083 			atmci_writel(host, ATMCI_IDR, ATMCI_NOTBUSY);
2084 			smp_wmb();
2085 			dev_dbg(&host->pdev->dev, "set pending notbusy\n");
2086 			atmci_set_pending(host, EVENT_NOTBUSY);
2087 			tasklet_schedule(&host->tasklet);
2088 		}
2089 
2090 		if (pending & ATMCI_RXRDY)
2091 			atmci_read_data_pio(host);
2092 		if (pending & ATMCI_TXRDY)
2093 			atmci_write_data_pio(host);
2094 
2095 		if (pending & ATMCI_CMDRDY) {
2096 			dev_dbg(&host->pdev->dev, "IRQ: cmd ready\n");
2097 			atmci_writel(host, ATMCI_IDR, ATMCI_CMDRDY);
2098 			host->cmd_status = status;
2099 			smp_wmb();
2100 			dev_dbg(&host->pdev->dev, "set pending cmd rdy\n");
2101 			atmci_set_pending(host, EVENT_CMD_RDY);
2102 			tasklet_schedule(&host->tasklet);
2103 		}
2104 
2105 		if (pending & (ATMCI_SDIOIRQA | ATMCI_SDIOIRQB))
2106 			atmci_sdio_interrupt(host, status);
2107 
2108 	} while (pass_count++ < 5);
2109 
2110 	return pass_count ? IRQ_HANDLED : IRQ_NONE;
2111 }
2112 
2113 static irqreturn_t atmci_detect_interrupt(int irq, void *dev_id)
2114 {
2115 	struct atmel_mci_slot	*slot = dev_id;
2116 
2117 	/*
2118 	 * Disable interrupts until the pin has stabilized and check
2119 	 * the state then. Use mod_timer() since we may be in the
2120 	 * middle of the timer routine when this interrupt triggers.
2121 	 */
2122 	disable_irq_nosync(irq);
2123 	mod_timer(&slot->detect_timer, jiffies + msecs_to_jiffies(20));
2124 
2125 	return IRQ_HANDLED;
2126 }
2127 
2128 static int __init atmci_init_slot(struct atmel_mci *host,
2129 		struct mci_slot_pdata *slot_data, unsigned int id,
2130 		u32 sdc_reg, u32 sdio_irq)
2131 {
2132 	struct mmc_host			*mmc;
2133 	struct atmel_mci_slot		*slot;
2134 
2135 	mmc = mmc_alloc_host(sizeof(struct atmel_mci_slot), &host->pdev->dev);
2136 	if (!mmc)
2137 		return -ENOMEM;
2138 
2139 	slot = mmc_priv(mmc);
2140 	slot->mmc = mmc;
2141 	slot->host = host;
2142 	slot->detect_pin = slot_data->detect_pin;
2143 	slot->wp_pin = slot_data->wp_pin;
2144 	slot->detect_is_active_high = slot_data->detect_is_active_high;
2145 	slot->sdc_reg = sdc_reg;
2146 	slot->sdio_irq = sdio_irq;
2147 
2148 	dev_dbg(&mmc->class_dev,
2149 	        "slot[%u]: bus_width=%u, detect_pin=%d, "
2150 		"detect_is_active_high=%s, wp_pin=%d\n",
2151 		id, slot_data->bus_width, slot_data->detect_pin,
2152 		slot_data->detect_is_active_high ? "true" : "false",
2153 		slot_data->wp_pin);
2154 
2155 	mmc->ops = &atmci_ops;
2156 	mmc->f_min = DIV_ROUND_UP(host->bus_hz, 512);
2157 	mmc->f_max = host->bus_hz / 2;
2158 	mmc->ocr_avail	= MMC_VDD_32_33 | MMC_VDD_33_34;
2159 	if (sdio_irq)
2160 		mmc->caps |= MMC_CAP_SDIO_IRQ;
2161 	if (host->caps.has_highspeed)
2162 		mmc->caps |= MMC_CAP_SD_HIGHSPEED;
2163 	/*
2164 	 * Without the read/write proof capability, it is strongly suggested to
2165 	 * use only one bit for data to prevent fifo underruns and overruns
2166 	 * which will corrupt data.
2167 	 */
2168 	if ((slot_data->bus_width >= 4) && host->caps.has_rwproof)
2169 		mmc->caps |= MMC_CAP_4_BIT_DATA;
2170 
2171 	if (atmci_get_version(host) < 0x200) {
2172 		mmc->max_segs = 256;
2173 		mmc->max_blk_size = 4095;
2174 		mmc->max_blk_count = 256;
2175 		mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
2176 		mmc->max_seg_size = mmc->max_blk_size * mmc->max_segs;
2177 	} else {
2178 		mmc->max_segs = 64;
2179 		mmc->max_req_size = 32768 * 512;
2180 		mmc->max_blk_size = 32768;
2181 		mmc->max_blk_count = 512;
2182 	}
2183 
2184 	/* Assume card is present initially */
2185 	set_bit(ATMCI_CARD_PRESENT, &slot->flags);
2186 	if (gpio_is_valid(slot->detect_pin)) {
2187 		if (gpio_request(slot->detect_pin, "mmc_detect")) {
2188 			dev_dbg(&mmc->class_dev, "no detect pin available\n");
2189 			slot->detect_pin = -EBUSY;
2190 		} else if (gpio_get_value(slot->detect_pin) ^
2191 				slot->detect_is_active_high) {
2192 			clear_bit(ATMCI_CARD_PRESENT, &slot->flags);
2193 		}
2194 	}
2195 
2196 	if (!gpio_is_valid(slot->detect_pin))
2197 		mmc->caps |= MMC_CAP_NEEDS_POLL;
2198 
2199 	if (gpio_is_valid(slot->wp_pin)) {
2200 		if (gpio_request(slot->wp_pin, "mmc_wp")) {
2201 			dev_dbg(&mmc->class_dev, "no WP pin available\n");
2202 			slot->wp_pin = -EBUSY;
2203 		}
2204 	}
2205 
2206 	host->slot[id] = slot;
2207 	mmc_add_host(mmc);
2208 
2209 	if (gpio_is_valid(slot->detect_pin)) {
2210 		int ret;
2211 
2212 		setup_timer(&slot->detect_timer, atmci_detect_change,
2213 				(unsigned long)slot);
2214 
2215 		ret = request_irq(gpio_to_irq(slot->detect_pin),
2216 				atmci_detect_interrupt,
2217 				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
2218 				"mmc-detect", slot);
2219 		if (ret) {
2220 			dev_dbg(&mmc->class_dev,
2221 				"could not request IRQ %d for detect pin\n",
2222 				gpio_to_irq(slot->detect_pin));
2223 			gpio_free(slot->detect_pin);
2224 			slot->detect_pin = -EBUSY;
2225 		}
2226 	}
2227 
2228 	atmci_init_debugfs(slot);
2229 
2230 	return 0;
2231 }
2232 
2233 static void __exit atmci_cleanup_slot(struct atmel_mci_slot *slot,
2234 		unsigned int id)
2235 {
2236 	/* Debugfs stuff is cleaned up by mmc core */
2237 
2238 	set_bit(ATMCI_SHUTDOWN, &slot->flags);
2239 	smp_wmb();
2240 
2241 	mmc_remove_host(slot->mmc);
2242 
2243 	if (gpio_is_valid(slot->detect_pin)) {
2244 		int pin = slot->detect_pin;
2245 
2246 		free_irq(gpio_to_irq(pin), slot);
2247 		del_timer_sync(&slot->detect_timer);
2248 		gpio_free(pin);
2249 	}
2250 	if (gpio_is_valid(slot->wp_pin))
2251 		gpio_free(slot->wp_pin);
2252 
2253 	slot->host->slot[id] = NULL;
2254 	mmc_free_host(slot->mmc);
2255 }
2256 
2257 static bool atmci_filter(struct dma_chan *chan, void *pdata)
2258 {
2259 	struct mci_platform_data *sl_pdata = pdata;
2260 	struct mci_dma_data *sl;
2261 
2262 	if (!sl_pdata)
2263 		return false;
2264 
2265 	sl = sl_pdata->dma_slave;
2266 	if (sl && find_slave_dev(sl) == chan->device->dev) {
2267 		chan->private = slave_data_ptr(sl);
2268 		return true;
2269 	} else {
2270 		return false;
2271 	}
2272 }
2273 
2274 static bool atmci_configure_dma(struct atmel_mci *host)
2275 {
2276 	struct mci_platform_data	*pdata;
2277 	dma_cap_mask_t mask;
2278 
2279 	if (host == NULL)
2280 		return false;
2281 
2282 	pdata = host->pdev->dev.platform_data;
2283 
2284 	dma_cap_zero(mask);
2285 	dma_cap_set(DMA_SLAVE, mask);
2286 
2287 	host->dma.chan = dma_request_slave_channel_compat(mask, atmci_filter, pdata,
2288 							  &host->pdev->dev, "rxtx");
2289 	if (!host->dma.chan) {
2290 		dev_warn(&host->pdev->dev, "no DMA channel available\n");
2291 		return false;
2292 	} else {
2293 		dev_info(&host->pdev->dev,
2294 					"using %s for DMA transfers\n",
2295 					dma_chan_name(host->dma.chan));
2296 
2297 		host->dma_conf.src_addr = host->mapbase + ATMCI_RDR;
2298 		host->dma_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
2299 		host->dma_conf.src_maxburst = 1;
2300 		host->dma_conf.dst_addr = host->mapbase + ATMCI_TDR;
2301 		host->dma_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
2302 		host->dma_conf.dst_maxburst = 1;
2303 		host->dma_conf.device_fc = false;
2304 		return true;
2305 	}
2306 }
2307 
2308 /*
2309  * HSMCI (High Speed MCI) module is not fully compatible with MCI module.
2310  * HSMCI provides DMA support and a new config register but no more supports
2311  * PDC.
2312  */
2313 static void __init atmci_get_cap(struct atmel_mci *host)
2314 {
2315 	unsigned int version;
2316 
2317 	version = atmci_get_version(host);
2318 	dev_info(&host->pdev->dev,
2319 			"version: 0x%x\n", version);
2320 
2321 	host->caps.has_dma_conf_reg = 0;
2322 	host->caps.has_pdc = ATMCI_PDC_CONNECTED;
2323 	host->caps.has_cfg_reg = 0;
2324 	host->caps.has_cstor_reg = 0;
2325 	host->caps.has_highspeed = 0;
2326 	host->caps.has_rwproof = 0;
2327 	host->caps.has_odd_clk_div = 0;
2328 	host->caps.has_bad_data_ordering = 1;
2329 	host->caps.need_reset_after_xfer = 1;
2330 	host->caps.need_blksz_mul_4 = 1;
2331 	host->caps.need_notbusy_for_read_ops = 0;
2332 
2333 	/* keep only major version number */
2334 	switch (version & 0xf00) {
2335 	case 0x500:
2336 		host->caps.has_odd_clk_div = 1;
2337 	case 0x400:
2338 	case 0x300:
2339 		host->caps.has_dma_conf_reg = 1;
2340 		host->caps.has_pdc = 0;
2341 		host->caps.has_cfg_reg = 1;
2342 		host->caps.has_cstor_reg = 1;
2343 		host->caps.has_highspeed = 1;
2344 	case 0x200:
2345 		host->caps.has_rwproof = 1;
2346 		host->caps.need_blksz_mul_4 = 0;
2347 		host->caps.need_notbusy_for_read_ops = 1;
2348 	case 0x100:
2349 		host->caps.has_bad_data_ordering = 0;
2350 		host->caps.need_reset_after_xfer = 0;
2351 	case 0x0:
2352 		break;
2353 	default:
2354 		host->caps.has_pdc = 0;
2355 		dev_warn(&host->pdev->dev,
2356 				"Unmanaged mci version, set minimum capabilities\n");
2357 		break;
2358 	}
2359 }
2360 
2361 static int __init atmci_probe(struct platform_device *pdev)
2362 {
2363 	struct mci_platform_data	*pdata;
2364 	struct atmel_mci		*host;
2365 	struct resource			*regs;
2366 	unsigned int			nr_slots;
2367 	int				irq;
2368 	int				ret;
2369 
2370 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2371 	if (!regs)
2372 		return -ENXIO;
2373 	pdata = pdev->dev.platform_data;
2374 	if (!pdata) {
2375 		pdata = atmci_of_init(pdev);
2376 		if (IS_ERR(pdata)) {
2377 			dev_err(&pdev->dev, "platform data not available\n");
2378 			return PTR_ERR(pdata);
2379 		}
2380 	}
2381 
2382 	irq = platform_get_irq(pdev, 0);
2383 	if (irq < 0)
2384 		return irq;
2385 
2386 	host = kzalloc(sizeof(struct atmel_mci), GFP_KERNEL);
2387 	if (!host)
2388 		return -ENOMEM;
2389 
2390 	host->pdev = pdev;
2391 	spin_lock_init(&host->lock);
2392 	INIT_LIST_HEAD(&host->queue);
2393 
2394 	host->mck = clk_get(&pdev->dev, "mci_clk");
2395 	if (IS_ERR(host->mck)) {
2396 		ret = PTR_ERR(host->mck);
2397 		goto err_clk_get;
2398 	}
2399 
2400 	ret = -ENOMEM;
2401 	host->regs = ioremap(regs->start, resource_size(regs));
2402 	if (!host->regs)
2403 		goto err_ioremap;
2404 
2405 	ret = clk_prepare_enable(host->mck);
2406 	if (ret)
2407 		goto err_request_irq;
2408 	atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
2409 	host->bus_hz = clk_get_rate(host->mck);
2410 	clk_disable_unprepare(host->mck);
2411 
2412 	host->mapbase = regs->start;
2413 
2414 	tasklet_init(&host->tasklet, atmci_tasklet_func, (unsigned long)host);
2415 
2416 	ret = request_irq(irq, atmci_interrupt, 0, dev_name(&pdev->dev), host);
2417 	if (ret)
2418 		goto err_request_irq;
2419 
2420 	/* Get MCI capabilities and set operations according to it */
2421 	atmci_get_cap(host);
2422 	if (atmci_configure_dma(host)) {
2423 		host->prepare_data = &atmci_prepare_data_dma;
2424 		host->submit_data = &atmci_submit_data_dma;
2425 		host->stop_transfer = &atmci_stop_transfer_dma;
2426 	} else if (host->caps.has_pdc) {
2427 		dev_info(&pdev->dev, "using PDC\n");
2428 		host->prepare_data = &atmci_prepare_data_pdc;
2429 		host->submit_data = &atmci_submit_data_pdc;
2430 		host->stop_transfer = &atmci_stop_transfer_pdc;
2431 	} else {
2432 		dev_info(&pdev->dev, "using PIO\n");
2433 		host->prepare_data = &atmci_prepare_data;
2434 		host->submit_data = &atmci_submit_data;
2435 		host->stop_transfer = &atmci_stop_transfer;
2436 	}
2437 
2438 	platform_set_drvdata(pdev, host);
2439 
2440 	setup_timer(&host->timer, atmci_timeout_timer, (unsigned long)host);
2441 
2442 	/* We need at least one slot to succeed */
2443 	nr_slots = 0;
2444 	ret = -ENODEV;
2445 	if (pdata->slot[0].bus_width) {
2446 		ret = atmci_init_slot(host, &pdata->slot[0],
2447 				0, ATMCI_SDCSEL_SLOT_A, ATMCI_SDIOIRQA);
2448 		if (!ret) {
2449 			nr_slots++;
2450 			host->buf_size = host->slot[0]->mmc->max_req_size;
2451 		}
2452 	}
2453 	if (pdata->slot[1].bus_width) {
2454 		ret = atmci_init_slot(host, &pdata->slot[1],
2455 				1, ATMCI_SDCSEL_SLOT_B, ATMCI_SDIOIRQB);
2456 		if (!ret) {
2457 			nr_slots++;
2458 			if (host->slot[1]->mmc->max_req_size > host->buf_size)
2459 				host->buf_size =
2460 					host->slot[1]->mmc->max_req_size;
2461 		}
2462 	}
2463 
2464 	if (!nr_slots) {
2465 		dev_err(&pdev->dev, "init failed: no slot defined\n");
2466 		goto err_init_slot;
2467 	}
2468 
2469 	if (!host->caps.has_rwproof) {
2470 		host->buffer = dma_alloc_coherent(&pdev->dev, host->buf_size,
2471 		                                  &host->buf_phys_addr,
2472 						  GFP_KERNEL);
2473 		if (!host->buffer) {
2474 			ret = -ENOMEM;
2475 			dev_err(&pdev->dev, "buffer allocation failed\n");
2476 			goto err_init_slot;
2477 		}
2478 	}
2479 
2480 	dev_info(&pdev->dev,
2481 			"Atmel MCI controller at 0x%08lx irq %d, %u slots\n",
2482 			host->mapbase, irq, nr_slots);
2483 
2484 	return 0;
2485 
2486 err_init_slot:
2487 	if (host->dma.chan)
2488 		dma_release_channel(host->dma.chan);
2489 	free_irq(irq, host);
2490 err_request_irq:
2491 	iounmap(host->regs);
2492 err_ioremap:
2493 	clk_put(host->mck);
2494 err_clk_get:
2495 	kfree(host);
2496 	return ret;
2497 }
2498 
2499 static int __exit atmci_remove(struct platform_device *pdev)
2500 {
2501 	struct atmel_mci	*host = platform_get_drvdata(pdev);
2502 	unsigned int		i;
2503 
2504 	if (host->buffer)
2505 		dma_free_coherent(&pdev->dev, host->buf_size,
2506 		                  host->buffer, host->buf_phys_addr);
2507 
2508 	for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
2509 		if (host->slot[i])
2510 			atmci_cleanup_slot(host->slot[i], i);
2511 	}
2512 
2513 	clk_prepare_enable(host->mck);
2514 	atmci_writel(host, ATMCI_IDR, ~0UL);
2515 	atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIDIS);
2516 	atmci_readl(host, ATMCI_SR);
2517 	clk_disable_unprepare(host->mck);
2518 
2519 	if (host->dma.chan)
2520 		dma_release_channel(host->dma.chan);
2521 
2522 	free_irq(platform_get_irq(pdev, 0), host);
2523 	iounmap(host->regs);
2524 
2525 	clk_put(host->mck);
2526 	kfree(host);
2527 
2528 	return 0;
2529 }
2530 
2531 static struct platform_driver atmci_driver = {
2532 	.remove		= __exit_p(atmci_remove),
2533 	.driver		= {
2534 		.name		= "atmel_mci",
2535 		.of_match_table	= of_match_ptr(atmci_dt_ids),
2536 	},
2537 };
2538 
2539 static int __init atmci_init(void)
2540 {
2541 	return platform_driver_probe(&atmci_driver, atmci_probe);
2542 }
2543 
2544 static void __exit atmci_exit(void)
2545 {
2546 	platform_driver_unregister(&atmci_driver);
2547 }
2548 
2549 late_initcall(atmci_init); /* try to load after dma driver when built-in */
2550 module_exit(atmci_exit);
2551 
2552 MODULE_DESCRIPTION("Atmel Multimedia Card Interface driver");
2553 MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
2554 MODULE_LICENSE("GPL v2");
2555