xref: /linux/drivers/mmc/host/atmel-mci.c (revision 439164663e5d1753360ff84ea4d5c598459e5d50)
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/platform_device.h>
23 #include <linux/scatterlist.h>
24 #include <linux/seq_file.h>
25 #include <linux/slab.h>
26 #include <linux/stat.h>
27 #include <linux/types.h>
28 
29 #include <linux/mmc/host.h>
30 #include <linux/mmc/sdio.h>
31 
32 #include <mach/atmel-mci.h>
33 #include <linux/atmel-mci.h>
34 #include <linux/atmel_pdc.h>
35 
36 #include <asm/io.h>
37 #include <asm/unaligned.h>
38 
39 #include <mach/cpu.h>
40 #include <mach/board.h>
41 
42 #include "atmel-mci-regs.h"
43 
44 #define ATMCI_DATA_ERROR_FLAGS	(ATMCI_DCRCE | ATMCI_DTOE | ATMCI_OVRE | ATMCI_UNRE)
45 #define ATMCI_DMA_THRESHOLD	16
46 
47 enum {
48 	EVENT_CMD_RDY = 0,
49 	EVENT_XFER_COMPLETE,
50 	EVENT_NOTBUSY,
51 	EVENT_DATA_ERROR,
52 };
53 
54 enum atmel_mci_state {
55 	STATE_IDLE = 0,
56 	STATE_SENDING_CMD,
57 	STATE_DATA_XFER,
58 	STATE_WAITING_NOTBUSY,
59 	STATE_SENDING_STOP,
60 	STATE_END_REQUEST,
61 };
62 
63 enum atmci_xfer_dir {
64 	XFER_RECEIVE = 0,
65 	XFER_TRANSMIT,
66 };
67 
68 enum atmci_pdc_buf {
69 	PDC_FIRST_BUF = 0,
70 	PDC_SECOND_BUF,
71 };
72 
73 struct atmel_mci_caps {
74 	bool    has_dma;
75 	bool    has_pdc;
76 	bool    has_cfg_reg;
77 	bool    has_cstor_reg;
78 	bool    has_highspeed;
79 	bool    has_rwproof;
80 	bool	has_odd_clk_div;
81 	bool	has_bad_data_ordering;
82 	bool	need_reset_after_xfer;
83 	bool	need_blksz_mul_4;
84 };
85 
86 struct atmel_mci_dma {
87 	struct dma_chan			*chan;
88 	struct dma_async_tx_descriptor	*data_desc;
89 };
90 
91 /**
92  * struct atmel_mci - MMC controller state shared between all slots
93  * @lock: Spinlock protecting the queue and associated data.
94  * @regs: Pointer to MMIO registers.
95  * @sg: Scatterlist entry currently being processed by PIO or PDC code.
96  * @pio_offset: Offset into the current scatterlist entry.
97  * @buffer: Buffer used if we don't have the r/w proof capability. We
98  *      don't have the time to switch pdc buffers so we have to use only
99  *      one buffer for the full transaction.
100  * @buf_size: size of the buffer.
101  * @phys_buf_addr: buffer address needed for pdc.
102  * @cur_slot: The slot which is currently using the controller.
103  * @mrq: The request currently being processed on @cur_slot,
104  *	or NULL if the controller is idle.
105  * @cmd: The command currently being sent to the card, or NULL.
106  * @data: The data currently being transferred, or NULL if no data
107  *	transfer is in progress.
108  * @data_size: just data->blocks * data->blksz.
109  * @dma: DMA client state.
110  * @data_chan: DMA channel being used for the current data transfer.
111  * @cmd_status: Snapshot of SR taken upon completion of the current
112  *	command. Only valid when EVENT_CMD_COMPLETE is pending.
113  * @data_status: Snapshot of SR taken upon completion of the current
114  *	data transfer. Only valid when EVENT_DATA_COMPLETE or
115  *	EVENT_DATA_ERROR is pending.
116  * @stop_cmdr: Value to be loaded into CMDR when the stop command is
117  *	to be sent.
118  * @tasklet: Tasklet running the request state machine.
119  * @pending_events: Bitmask of events flagged by the interrupt handler
120  *	to be processed by the tasklet.
121  * @completed_events: Bitmask of events which the state machine has
122  *	processed.
123  * @state: Tasklet state.
124  * @queue: List of slots waiting for access to the controller.
125  * @need_clock_update: Update the clock rate before the next request.
126  * @need_reset: Reset controller before next request.
127  * @timer: Timer to balance the data timeout error flag which cannot rise.
128  * @mode_reg: Value of the MR register.
129  * @cfg_reg: Value of the CFG register.
130  * @bus_hz: The rate of @mck in Hz. This forms the basis for MMC bus
131  *	rate and timeout calculations.
132  * @mapbase: Physical address of the MMIO registers.
133  * @mck: The peripheral bus clock hooked up to the MMC controller.
134  * @pdev: Platform device associated with the MMC controller.
135  * @slot: Slots sharing this MMC controller.
136  * @caps: MCI capabilities depending on MCI version.
137  * @prepare_data: function to setup MCI before data transfer which
138  * depends on MCI capabilities.
139  * @submit_data: function to start data transfer which depends on MCI
140  * capabilities.
141  * @stop_transfer: function to stop data transfer which depends on MCI
142  * capabilities.
143  *
144  * Locking
145  * =======
146  *
147  * @lock is a softirq-safe spinlock protecting @queue as well as
148  * @cur_slot, @mrq and @state. These must always be updated
149  * at the same time while holding @lock.
150  *
151  * @lock also protects mode_reg and need_clock_update since these are
152  * used to synchronize mode register updates with the queue
153  * processing.
154  *
155  * The @mrq field of struct atmel_mci_slot is also protected by @lock,
156  * and must always be written at the same time as the slot is added to
157  * @queue.
158  *
159  * @pending_events and @completed_events are accessed using atomic bit
160  * operations, so they don't need any locking.
161  *
162  * None of the fields touched by the interrupt handler need any
163  * locking. However, ordering is important: Before EVENT_DATA_ERROR or
164  * EVENT_DATA_COMPLETE is set in @pending_events, all data-related
165  * interrupts must be disabled and @data_status updated with a
166  * snapshot of SR. Similarly, before EVENT_CMD_COMPLETE is set, the
167  * CMDRDY interrupt must be disabled and @cmd_status updated with a
168  * snapshot of SR, and before EVENT_XFER_COMPLETE can be set, the
169  * bytes_xfered field of @data must be written. This is ensured by
170  * using barriers.
171  */
172 struct atmel_mci {
173 	spinlock_t		lock;
174 	void __iomem		*regs;
175 
176 	struct scatterlist	*sg;
177 	unsigned int		pio_offset;
178 	unsigned int		*buffer;
179 	unsigned int		buf_size;
180 	dma_addr_t		buf_phys_addr;
181 
182 	struct atmel_mci_slot	*cur_slot;
183 	struct mmc_request	*mrq;
184 	struct mmc_command	*cmd;
185 	struct mmc_data		*data;
186 	unsigned int		data_size;
187 
188 	struct atmel_mci_dma	dma;
189 	struct dma_chan		*data_chan;
190 	struct dma_slave_config	dma_conf;
191 
192 	u32			cmd_status;
193 	u32			data_status;
194 	u32			stop_cmdr;
195 
196 	struct tasklet_struct	tasklet;
197 	unsigned long		pending_events;
198 	unsigned long		completed_events;
199 	enum atmel_mci_state	state;
200 	struct list_head	queue;
201 
202 	bool			need_clock_update;
203 	bool			need_reset;
204 	struct timer_list	timer;
205 	u32			mode_reg;
206 	u32			cfg_reg;
207 	unsigned long		bus_hz;
208 	unsigned long		mapbase;
209 	struct clk		*mck;
210 	struct platform_device	*pdev;
211 
212 	struct atmel_mci_slot	*slot[ATMCI_MAX_NR_SLOTS];
213 
214 	struct atmel_mci_caps   caps;
215 
216 	u32 (*prepare_data)(struct atmel_mci *host, struct mmc_data *data);
217 	void (*submit_data)(struct atmel_mci *host, struct mmc_data *data);
218 	void (*stop_transfer)(struct atmel_mci *host);
219 };
220 
221 /**
222  * struct atmel_mci_slot - MMC slot state
223  * @mmc: The mmc_host representing this slot.
224  * @host: The MMC controller this slot is using.
225  * @sdc_reg: Value of SDCR to be written before using this slot.
226  * @sdio_irq: SDIO irq mask for this slot.
227  * @mrq: mmc_request currently being processed or waiting to be
228  *	processed, or NULL when the slot is idle.
229  * @queue_node: List node for placing this node in the @queue list of
230  *	&struct atmel_mci.
231  * @clock: Clock rate configured by set_ios(). Protected by host->lock.
232  * @flags: Random state bits associated with the slot.
233  * @detect_pin: GPIO pin used for card detection, or negative if not
234  *	available.
235  * @wp_pin: GPIO pin used for card write protect sending, or negative
236  *	if not available.
237  * @detect_is_active_high: The state of the detect pin when it is active.
238  * @detect_timer: Timer used for debouncing @detect_pin interrupts.
239  */
240 struct atmel_mci_slot {
241 	struct mmc_host		*mmc;
242 	struct atmel_mci	*host;
243 
244 	u32			sdc_reg;
245 	u32			sdio_irq;
246 
247 	struct mmc_request	*mrq;
248 	struct list_head	queue_node;
249 
250 	unsigned int		clock;
251 	unsigned long		flags;
252 #define ATMCI_CARD_PRESENT	0
253 #define ATMCI_CARD_NEED_INIT	1
254 #define ATMCI_SHUTDOWN		2
255 #define ATMCI_SUSPENDED		3
256 
257 	int			detect_pin;
258 	int			wp_pin;
259 	bool			detect_is_active_high;
260 
261 	struct timer_list	detect_timer;
262 };
263 
264 #define atmci_test_and_clear_pending(host, event)		\
265 	test_and_clear_bit(event, &host->pending_events)
266 #define atmci_set_completed(host, event)			\
267 	set_bit(event, &host->completed_events)
268 #define atmci_set_pending(host, event)				\
269 	set_bit(event, &host->pending_events)
270 
271 /*
272  * The debugfs stuff below is mostly optimized away when
273  * CONFIG_DEBUG_FS is not set.
274  */
275 static int atmci_req_show(struct seq_file *s, void *v)
276 {
277 	struct atmel_mci_slot	*slot = s->private;
278 	struct mmc_request	*mrq;
279 	struct mmc_command	*cmd;
280 	struct mmc_command	*stop;
281 	struct mmc_data		*data;
282 
283 	/* Make sure we get a consistent snapshot */
284 	spin_lock_bh(&slot->host->lock);
285 	mrq = slot->mrq;
286 
287 	if (mrq) {
288 		cmd = mrq->cmd;
289 		data = mrq->data;
290 		stop = mrq->stop;
291 
292 		if (cmd)
293 			seq_printf(s,
294 				"CMD%u(0x%x) flg %x rsp %x %x %x %x err %d\n",
295 				cmd->opcode, cmd->arg, cmd->flags,
296 				cmd->resp[0], cmd->resp[1], cmd->resp[2],
297 				cmd->resp[3], cmd->error);
298 		if (data)
299 			seq_printf(s, "DATA %u / %u * %u flg %x err %d\n",
300 				data->bytes_xfered, data->blocks,
301 				data->blksz, data->flags, data->error);
302 		if (stop)
303 			seq_printf(s,
304 				"CMD%u(0x%x) flg %x rsp %x %x %x %x err %d\n",
305 				stop->opcode, stop->arg, stop->flags,
306 				stop->resp[0], stop->resp[1], stop->resp[2],
307 				stop->resp[3], stop->error);
308 	}
309 
310 	spin_unlock_bh(&slot->host->lock);
311 
312 	return 0;
313 }
314 
315 static int atmci_req_open(struct inode *inode, struct file *file)
316 {
317 	return single_open(file, atmci_req_show, inode->i_private);
318 }
319 
320 static const struct file_operations atmci_req_fops = {
321 	.owner		= THIS_MODULE,
322 	.open		= atmci_req_open,
323 	.read		= seq_read,
324 	.llseek		= seq_lseek,
325 	.release	= single_release,
326 };
327 
328 static void atmci_show_status_reg(struct seq_file *s,
329 		const char *regname, u32 value)
330 {
331 	static const char	*sr_bit[] = {
332 		[0]	= "CMDRDY",
333 		[1]	= "RXRDY",
334 		[2]	= "TXRDY",
335 		[3]	= "BLKE",
336 		[4]	= "DTIP",
337 		[5]	= "NOTBUSY",
338 		[6]	= "ENDRX",
339 		[7]	= "ENDTX",
340 		[8]	= "SDIOIRQA",
341 		[9]	= "SDIOIRQB",
342 		[12]	= "SDIOWAIT",
343 		[14]	= "RXBUFF",
344 		[15]	= "TXBUFE",
345 		[16]	= "RINDE",
346 		[17]	= "RDIRE",
347 		[18]	= "RCRCE",
348 		[19]	= "RENDE",
349 		[20]	= "RTOE",
350 		[21]	= "DCRCE",
351 		[22]	= "DTOE",
352 		[23]	= "CSTOE",
353 		[24]	= "BLKOVRE",
354 		[25]	= "DMADONE",
355 		[26]	= "FIFOEMPTY",
356 		[27]	= "XFRDONE",
357 		[30]	= "OVRE",
358 		[31]	= "UNRE",
359 	};
360 	unsigned int		i;
361 
362 	seq_printf(s, "%s:\t0x%08x", regname, value);
363 	for (i = 0; i < ARRAY_SIZE(sr_bit); i++) {
364 		if (value & (1 << i)) {
365 			if (sr_bit[i])
366 				seq_printf(s, " %s", sr_bit[i]);
367 			else
368 				seq_puts(s, " UNKNOWN");
369 		}
370 	}
371 	seq_putc(s, '\n');
372 }
373 
374 static int atmci_regs_show(struct seq_file *s, void *v)
375 {
376 	struct atmel_mci	*host = s->private;
377 	u32			*buf;
378 
379 	buf = kmalloc(ATMCI_REGS_SIZE, GFP_KERNEL);
380 	if (!buf)
381 		return -ENOMEM;
382 
383 	/*
384 	 * Grab a more or less consistent snapshot. Note that we're
385 	 * not disabling interrupts, so IMR and SR may not be
386 	 * consistent.
387 	 */
388 	spin_lock_bh(&host->lock);
389 	clk_enable(host->mck);
390 	memcpy_fromio(buf, host->regs, ATMCI_REGS_SIZE);
391 	clk_disable(host->mck);
392 	spin_unlock_bh(&host->lock);
393 
394 	seq_printf(s, "MR:\t0x%08x%s%s ",
395 			buf[ATMCI_MR / 4],
396 			buf[ATMCI_MR / 4] & ATMCI_MR_RDPROOF ? " RDPROOF" : "",
397 			buf[ATMCI_MR / 4] & ATMCI_MR_WRPROOF ? " WRPROOF" : "");
398 	if (host->caps.has_odd_clk_div)
399 		seq_printf(s, "{CLKDIV,CLKODD}=%u\n",
400 				((buf[ATMCI_MR / 4] & 0xff) << 1)
401 				| ((buf[ATMCI_MR / 4] >> 16) & 1));
402 	else
403 		seq_printf(s, "CLKDIV=%u\n",
404 				(buf[ATMCI_MR / 4] & 0xff));
405 	seq_printf(s, "DTOR:\t0x%08x\n", buf[ATMCI_DTOR / 4]);
406 	seq_printf(s, "SDCR:\t0x%08x\n", buf[ATMCI_SDCR / 4]);
407 	seq_printf(s, "ARGR:\t0x%08x\n", buf[ATMCI_ARGR / 4]);
408 	seq_printf(s, "BLKR:\t0x%08x BCNT=%u BLKLEN=%u\n",
409 			buf[ATMCI_BLKR / 4],
410 			buf[ATMCI_BLKR / 4] & 0xffff,
411 			(buf[ATMCI_BLKR / 4] >> 16) & 0xffff);
412 	if (host->caps.has_cstor_reg)
413 		seq_printf(s, "CSTOR:\t0x%08x\n", buf[ATMCI_CSTOR / 4]);
414 
415 	/* Don't read RSPR and RDR; it will consume the data there */
416 
417 	atmci_show_status_reg(s, "SR", buf[ATMCI_SR / 4]);
418 	atmci_show_status_reg(s, "IMR", buf[ATMCI_IMR / 4]);
419 
420 	if (host->caps.has_dma) {
421 		u32 val;
422 
423 		val = buf[ATMCI_DMA / 4];
424 		seq_printf(s, "DMA:\t0x%08x OFFSET=%u CHKSIZE=%u%s\n",
425 				val, val & 3,
426 				((val >> 4) & 3) ?
427 					1 << (((val >> 4) & 3) + 1) : 1,
428 				val & ATMCI_DMAEN ? " DMAEN" : "");
429 	}
430 	if (host->caps.has_cfg_reg) {
431 		u32 val;
432 
433 		val = buf[ATMCI_CFG / 4];
434 		seq_printf(s, "CFG:\t0x%08x%s%s%s%s\n",
435 				val,
436 				val & ATMCI_CFG_FIFOMODE_1DATA ? " FIFOMODE_ONE_DATA" : "",
437 				val & ATMCI_CFG_FERRCTRL_COR ? " FERRCTRL_CLEAR_ON_READ" : "",
438 				val & ATMCI_CFG_HSMODE ? " HSMODE" : "",
439 				val & ATMCI_CFG_LSYNC ? " LSYNC" : "");
440 	}
441 
442 	kfree(buf);
443 
444 	return 0;
445 }
446 
447 static int atmci_regs_open(struct inode *inode, struct file *file)
448 {
449 	return single_open(file, atmci_regs_show, inode->i_private);
450 }
451 
452 static const struct file_operations atmci_regs_fops = {
453 	.owner		= THIS_MODULE,
454 	.open		= atmci_regs_open,
455 	.read		= seq_read,
456 	.llseek		= seq_lseek,
457 	.release	= single_release,
458 };
459 
460 static void atmci_init_debugfs(struct atmel_mci_slot *slot)
461 {
462 	struct mmc_host		*mmc = slot->mmc;
463 	struct atmel_mci	*host = slot->host;
464 	struct dentry		*root;
465 	struct dentry		*node;
466 
467 	root = mmc->debugfs_root;
468 	if (!root)
469 		return;
470 
471 	node = debugfs_create_file("regs", S_IRUSR, root, host,
472 			&atmci_regs_fops);
473 	if (IS_ERR(node))
474 		return;
475 	if (!node)
476 		goto err;
477 
478 	node = debugfs_create_file("req", S_IRUSR, root, slot, &atmci_req_fops);
479 	if (!node)
480 		goto err;
481 
482 	node = debugfs_create_u32("state", S_IRUSR, root, (u32 *)&host->state);
483 	if (!node)
484 		goto err;
485 
486 	node = debugfs_create_x32("pending_events", S_IRUSR, root,
487 				     (u32 *)&host->pending_events);
488 	if (!node)
489 		goto err;
490 
491 	node = debugfs_create_x32("completed_events", S_IRUSR, root,
492 				     (u32 *)&host->completed_events);
493 	if (!node)
494 		goto err;
495 
496 	return;
497 
498 err:
499 	dev_err(&mmc->class_dev, "failed to initialize debugfs for slot\n");
500 }
501 
502 static inline unsigned int atmci_get_version(struct atmel_mci *host)
503 {
504 	return atmci_readl(host, ATMCI_VERSION) & 0x00000fff;
505 }
506 
507 static void atmci_timeout_timer(unsigned long data)
508 {
509 	struct atmel_mci *host;
510 
511 	host = (struct atmel_mci *)data;
512 
513 	dev_dbg(&host->pdev->dev, "software timeout\n");
514 
515 	if (host->mrq->cmd->data) {
516 		host->mrq->cmd->data->error = -ETIMEDOUT;
517 		host->data = NULL;
518 	} else {
519 		host->mrq->cmd->error = -ETIMEDOUT;
520 		host->cmd = NULL;
521 	}
522 	host->need_reset = 1;
523 	host->state = STATE_END_REQUEST;
524 	smp_wmb();
525 	tasklet_schedule(&host->tasklet);
526 }
527 
528 static inline unsigned int atmci_ns_to_clocks(struct atmel_mci *host,
529 					unsigned int ns)
530 {
531 	/*
532 	 * It is easier here to use us instead of ns for the timeout,
533 	 * it prevents from overflows during calculation.
534 	 */
535 	unsigned int us = DIV_ROUND_UP(ns, 1000);
536 
537 	/* Maximum clock frequency is host->bus_hz/2 */
538 	return us * (DIV_ROUND_UP(host->bus_hz, 2000000));
539 }
540 
541 static void atmci_set_timeout(struct atmel_mci *host,
542 		struct atmel_mci_slot *slot, struct mmc_data *data)
543 {
544 	static unsigned	dtomul_to_shift[] = {
545 		0, 4, 7, 8, 10, 12, 16, 20
546 	};
547 	unsigned	timeout;
548 	unsigned	dtocyc;
549 	unsigned	dtomul;
550 
551 	timeout = atmci_ns_to_clocks(host, data->timeout_ns)
552 		+ data->timeout_clks;
553 
554 	for (dtomul = 0; dtomul < 8; dtomul++) {
555 		unsigned shift = dtomul_to_shift[dtomul];
556 		dtocyc = (timeout + (1 << shift) - 1) >> shift;
557 		if (dtocyc < 15)
558 			break;
559 	}
560 
561 	if (dtomul >= 8) {
562 		dtomul = 7;
563 		dtocyc = 15;
564 	}
565 
566 	dev_vdbg(&slot->mmc->class_dev, "setting timeout to %u cycles\n",
567 			dtocyc << dtomul_to_shift[dtomul]);
568 	atmci_writel(host, ATMCI_DTOR, (ATMCI_DTOMUL(dtomul) | ATMCI_DTOCYC(dtocyc)));
569 }
570 
571 /*
572  * Return mask with command flags to be enabled for this command.
573  */
574 static u32 atmci_prepare_command(struct mmc_host *mmc,
575 				 struct mmc_command *cmd)
576 {
577 	struct mmc_data	*data;
578 	u32		cmdr;
579 
580 	cmd->error = -EINPROGRESS;
581 
582 	cmdr = ATMCI_CMDR_CMDNB(cmd->opcode);
583 
584 	if (cmd->flags & MMC_RSP_PRESENT) {
585 		if (cmd->flags & MMC_RSP_136)
586 			cmdr |= ATMCI_CMDR_RSPTYP_136BIT;
587 		else
588 			cmdr |= ATMCI_CMDR_RSPTYP_48BIT;
589 	}
590 
591 	/*
592 	 * This should really be MAXLAT_5 for CMD2 and ACMD41, but
593 	 * it's too difficult to determine whether this is an ACMD or
594 	 * not. Better make it 64.
595 	 */
596 	cmdr |= ATMCI_CMDR_MAXLAT_64CYC;
597 
598 	if (mmc->ios.bus_mode == MMC_BUSMODE_OPENDRAIN)
599 		cmdr |= ATMCI_CMDR_OPDCMD;
600 
601 	data = cmd->data;
602 	if (data) {
603 		cmdr |= ATMCI_CMDR_START_XFER;
604 
605 		if (cmd->opcode == SD_IO_RW_EXTENDED) {
606 			cmdr |= ATMCI_CMDR_SDIO_BLOCK;
607 		} else {
608 			if (data->flags & MMC_DATA_STREAM)
609 				cmdr |= ATMCI_CMDR_STREAM;
610 			else if (data->blocks > 1)
611 				cmdr |= ATMCI_CMDR_MULTI_BLOCK;
612 			else
613 				cmdr |= ATMCI_CMDR_BLOCK;
614 		}
615 
616 		if (data->flags & MMC_DATA_READ)
617 			cmdr |= ATMCI_CMDR_TRDIR_READ;
618 	}
619 
620 	return cmdr;
621 }
622 
623 static void atmci_send_command(struct atmel_mci *host,
624 		struct mmc_command *cmd, u32 cmd_flags)
625 {
626 	WARN_ON(host->cmd);
627 	host->cmd = cmd;
628 
629 	dev_vdbg(&host->pdev->dev,
630 			"start command: ARGR=0x%08x CMDR=0x%08x\n",
631 			cmd->arg, cmd_flags);
632 
633 	atmci_writel(host, ATMCI_ARGR, cmd->arg);
634 	atmci_writel(host, ATMCI_CMDR, cmd_flags);
635 }
636 
637 static void atmci_send_stop_cmd(struct atmel_mci *host, struct mmc_data *data)
638 {
639 	dev_dbg(&host->pdev->dev, "send stop command\n");
640 	atmci_send_command(host, data->stop, host->stop_cmdr);
641 	atmci_writel(host, ATMCI_IER, ATMCI_CMDRDY);
642 }
643 
644 /*
645  * Configure given PDC buffer taking care of alignement issues.
646  * Update host->data_size and host->sg.
647  */
648 static void atmci_pdc_set_single_buf(struct atmel_mci *host,
649 	enum atmci_xfer_dir dir, enum atmci_pdc_buf buf_nb)
650 {
651 	u32 pointer_reg, counter_reg;
652 	unsigned int buf_size;
653 
654 	if (dir == XFER_RECEIVE) {
655 		pointer_reg = ATMEL_PDC_RPR;
656 		counter_reg = ATMEL_PDC_RCR;
657 	} else {
658 		pointer_reg = ATMEL_PDC_TPR;
659 		counter_reg = ATMEL_PDC_TCR;
660 	}
661 
662 	if (buf_nb == PDC_SECOND_BUF) {
663 		pointer_reg += ATMEL_PDC_SCND_BUF_OFF;
664 		counter_reg += ATMEL_PDC_SCND_BUF_OFF;
665 	}
666 
667 	if (!host->caps.has_rwproof) {
668 		buf_size = host->buf_size;
669 		atmci_writel(host, pointer_reg, host->buf_phys_addr);
670 	} else {
671 		buf_size = sg_dma_len(host->sg);
672 		atmci_writel(host, pointer_reg, sg_dma_address(host->sg));
673 	}
674 
675 	if (host->data_size <= buf_size) {
676 		if (host->data_size & 0x3) {
677 			/* If size is different from modulo 4, transfer bytes */
678 			atmci_writel(host, counter_reg, host->data_size);
679 			atmci_writel(host, ATMCI_MR, host->mode_reg | ATMCI_MR_PDCFBYTE);
680 		} else {
681 			/* Else transfer 32-bits words */
682 			atmci_writel(host, counter_reg, host->data_size / 4);
683 		}
684 		host->data_size = 0;
685 	} else {
686 		/* We assume the size of a page is 32-bits aligned */
687 		atmci_writel(host, counter_reg, sg_dma_len(host->sg) / 4);
688 		host->data_size -= sg_dma_len(host->sg);
689 		if (host->data_size)
690 			host->sg = sg_next(host->sg);
691 	}
692 }
693 
694 /*
695  * Configure PDC buffer according to the data size ie configuring one or two
696  * buffers. Don't use this function if you want to configure only the second
697  * buffer. In this case, use atmci_pdc_set_single_buf.
698  */
699 static void atmci_pdc_set_both_buf(struct atmel_mci *host, int dir)
700 {
701 	atmci_pdc_set_single_buf(host, dir, PDC_FIRST_BUF);
702 	if (host->data_size)
703 		atmci_pdc_set_single_buf(host, dir, PDC_SECOND_BUF);
704 }
705 
706 /*
707  * Unmap sg lists, called when transfer is finished.
708  */
709 static void atmci_pdc_cleanup(struct atmel_mci *host)
710 {
711 	struct mmc_data         *data = host->data;
712 
713 	if (data)
714 		dma_unmap_sg(&host->pdev->dev,
715 				data->sg, data->sg_len,
716 				((data->flags & MMC_DATA_WRITE)
717 				 ? DMA_TO_DEVICE : DMA_FROM_DEVICE));
718 }
719 
720 /*
721  * Disable PDC transfers. Update pending flags to EVENT_XFER_COMPLETE after
722  * having received ATMCI_TXBUFE or ATMCI_RXBUFF interrupt. Enable ATMCI_NOTBUSY
723  * interrupt needed for both transfer directions.
724  */
725 static void atmci_pdc_complete(struct atmel_mci *host)
726 {
727 	int transfer_size = host->data->blocks * host->data->blksz;
728 	int i;
729 
730 	atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
731 
732 	if ((!host->caps.has_rwproof)
733 	    && (host->data->flags & MMC_DATA_READ)) {
734 		if (host->caps.has_bad_data_ordering)
735 			for (i = 0; i < transfer_size; i++)
736 				host->buffer[i] = swab32(host->buffer[i]);
737 		sg_copy_from_buffer(host->data->sg, host->data->sg_len,
738 		                    host->buffer, transfer_size);
739 	}
740 
741 	atmci_pdc_cleanup(host);
742 
743 	/*
744 	 * If the card was removed, data will be NULL. No point trying
745 	 * to send the stop command or waiting for NBUSY in this case.
746 	 */
747 	if (host->data) {
748 		dev_dbg(&host->pdev->dev,
749 		        "(%s) set pending xfer complete\n", __func__);
750 		atmci_set_pending(host, EVENT_XFER_COMPLETE);
751 		tasklet_schedule(&host->tasklet);
752 	}
753 }
754 
755 static void atmci_dma_cleanup(struct atmel_mci *host)
756 {
757 	struct mmc_data                 *data = host->data;
758 
759 	if (data)
760 		dma_unmap_sg(host->dma.chan->device->dev,
761 				data->sg, data->sg_len,
762 				((data->flags & MMC_DATA_WRITE)
763 				 ? DMA_TO_DEVICE : DMA_FROM_DEVICE));
764 }
765 
766 /*
767  * This function is called by the DMA driver from tasklet context.
768  */
769 static void atmci_dma_complete(void *arg)
770 {
771 	struct atmel_mci	*host = arg;
772 	struct mmc_data		*data = host->data;
773 
774 	dev_vdbg(&host->pdev->dev, "DMA complete\n");
775 
776 	if (host->caps.has_dma)
777 		/* Disable DMA hardware handshaking on MCI */
778 		atmci_writel(host, ATMCI_DMA, atmci_readl(host, ATMCI_DMA) & ~ATMCI_DMAEN);
779 
780 	atmci_dma_cleanup(host);
781 
782 	/*
783 	 * If the card was removed, data will be NULL. No point trying
784 	 * to send the stop command or waiting for NBUSY in this case.
785 	 */
786 	if (data) {
787 		dev_dbg(&host->pdev->dev,
788 		        "(%s) set pending xfer complete\n", __func__);
789 		atmci_set_pending(host, EVENT_XFER_COMPLETE);
790 		tasklet_schedule(&host->tasklet);
791 
792 		/*
793 		 * Regardless of what the documentation says, we have
794 		 * to wait for NOTBUSY even after block read
795 		 * operations.
796 		 *
797 		 * When the DMA transfer is complete, the controller
798 		 * may still be reading the CRC from the card, i.e.
799 		 * the data transfer is still in progress and we
800 		 * haven't seen all the potential error bits yet.
801 		 *
802 		 * The interrupt handler will schedule a different
803 		 * tasklet to finish things up when the data transfer
804 		 * is completely done.
805 		 *
806 		 * We may not complete the mmc request here anyway
807 		 * because the mmc layer may call back and cause us to
808 		 * violate the "don't submit new operations from the
809 		 * completion callback" rule of the dma engine
810 		 * framework.
811 		 */
812 		atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
813 	}
814 }
815 
816 /*
817  * Returns a mask of interrupt flags to be enabled after the whole
818  * request has been prepared.
819  */
820 static u32 atmci_prepare_data(struct atmel_mci *host, struct mmc_data *data)
821 {
822 	u32 iflags;
823 
824 	data->error = -EINPROGRESS;
825 
826 	host->sg = data->sg;
827 	host->data = data;
828 	host->data_chan = NULL;
829 
830 	iflags = ATMCI_DATA_ERROR_FLAGS;
831 
832 	/*
833 	 * Errata: MMC data write operation with less than 12
834 	 * bytes is impossible.
835 	 *
836 	 * Errata: MCI Transmit Data Register (TDR) FIFO
837 	 * corruption when length is not multiple of 4.
838 	 */
839 	if (data->blocks * data->blksz < 12
840 			|| (data->blocks * data->blksz) & 3)
841 		host->need_reset = true;
842 
843 	host->pio_offset = 0;
844 	if (data->flags & MMC_DATA_READ)
845 		iflags |= ATMCI_RXRDY;
846 	else
847 		iflags |= ATMCI_TXRDY;
848 
849 	return iflags;
850 }
851 
852 /*
853  * Set interrupt flags and set block length into the MCI mode register even
854  * if this value is also accessible in the MCI block register. It seems to be
855  * necessary before the High Speed MCI version. It also map sg and configure
856  * PDC registers.
857  */
858 static u32
859 atmci_prepare_data_pdc(struct atmel_mci *host, struct mmc_data *data)
860 {
861 	u32 iflags, tmp;
862 	unsigned int sg_len;
863 	enum dma_data_direction dir;
864 	int i;
865 
866 	data->error = -EINPROGRESS;
867 
868 	host->data = data;
869 	host->sg = data->sg;
870 	iflags = ATMCI_DATA_ERROR_FLAGS;
871 
872 	/* Enable pdc mode */
873 	atmci_writel(host, ATMCI_MR, host->mode_reg | ATMCI_MR_PDCMODE);
874 
875 	if (data->flags & MMC_DATA_READ) {
876 		dir = DMA_FROM_DEVICE;
877 		iflags |= ATMCI_ENDRX | ATMCI_RXBUFF;
878 	} else {
879 		dir = DMA_TO_DEVICE;
880 		iflags |= ATMCI_ENDTX | ATMCI_TXBUFE | ATMCI_BLKE;
881 	}
882 
883 	/* Set BLKLEN */
884 	tmp = atmci_readl(host, ATMCI_MR);
885 	tmp &= 0x0000ffff;
886 	tmp |= ATMCI_BLKLEN(data->blksz);
887 	atmci_writel(host, ATMCI_MR, tmp);
888 
889 	/* Configure PDC */
890 	host->data_size = data->blocks * data->blksz;
891 	sg_len = dma_map_sg(&host->pdev->dev, data->sg, data->sg_len, dir);
892 
893 	if ((!host->caps.has_rwproof)
894 	    && (host->data->flags & MMC_DATA_WRITE)) {
895 		sg_copy_to_buffer(host->data->sg, host->data->sg_len,
896 		                  host->buffer, host->data_size);
897 		if (host->caps.has_bad_data_ordering)
898 			for (i = 0; i < host->data_size; i++)
899 				host->buffer[i] = swab32(host->buffer[i]);
900 	}
901 
902 	if (host->data_size)
903 		atmci_pdc_set_both_buf(host,
904 			((dir == DMA_FROM_DEVICE) ? XFER_RECEIVE : XFER_TRANSMIT));
905 
906 	return iflags;
907 }
908 
909 static u32
910 atmci_prepare_data_dma(struct atmel_mci *host, struct mmc_data *data)
911 {
912 	struct dma_chan			*chan;
913 	struct dma_async_tx_descriptor	*desc;
914 	struct scatterlist		*sg;
915 	unsigned int			i;
916 	enum dma_data_direction		direction;
917 	enum dma_transfer_direction	slave_dirn;
918 	unsigned int			sglen;
919 	u32				maxburst;
920 	u32 iflags;
921 
922 	data->error = -EINPROGRESS;
923 
924 	WARN_ON(host->data);
925 	host->sg = NULL;
926 	host->data = data;
927 
928 	iflags = ATMCI_DATA_ERROR_FLAGS;
929 
930 	/*
931 	 * We don't do DMA on "complex" transfers, i.e. with
932 	 * non-word-aligned buffers or lengths. Also, we don't bother
933 	 * with all the DMA setup overhead for short transfers.
934 	 */
935 	if (data->blocks * data->blksz < ATMCI_DMA_THRESHOLD)
936 		return atmci_prepare_data(host, data);
937 	if (data->blksz & 3)
938 		return atmci_prepare_data(host, data);
939 
940 	for_each_sg(data->sg, sg, data->sg_len, i) {
941 		if (sg->offset & 3 || sg->length & 3)
942 			return atmci_prepare_data(host, data);
943 	}
944 
945 	/* If we don't have a channel, we can't do DMA */
946 	chan = host->dma.chan;
947 	if (chan)
948 		host->data_chan = chan;
949 
950 	if (!chan)
951 		return -ENODEV;
952 
953 	if (data->flags & MMC_DATA_READ) {
954 		direction = DMA_FROM_DEVICE;
955 		host->dma_conf.direction = slave_dirn = DMA_DEV_TO_MEM;
956 		maxburst = atmci_convert_chksize(host->dma_conf.src_maxburst);
957 	} else {
958 		direction = DMA_TO_DEVICE;
959 		host->dma_conf.direction = slave_dirn = DMA_MEM_TO_DEV;
960 		maxburst = atmci_convert_chksize(host->dma_conf.dst_maxburst);
961 	}
962 
963 	atmci_writel(host, ATMCI_DMA, ATMCI_DMA_CHKSIZE(maxburst) | ATMCI_DMAEN);
964 
965 	sglen = dma_map_sg(chan->device->dev, data->sg,
966 			data->sg_len, direction);
967 
968 	dmaengine_slave_config(chan, &host->dma_conf);
969 	desc = dmaengine_prep_slave_sg(chan,
970 			data->sg, sglen, slave_dirn,
971 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
972 	if (!desc)
973 		goto unmap_exit;
974 
975 	host->dma.data_desc = desc;
976 	desc->callback = atmci_dma_complete;
977 	desc->callback_param = host;
978 
979 	return iflags;
980 unmap_exit:
981 	dma_unmap_sg(chan->device->dev, data->sg, data->sg_len, direction);
982 	return -ENOMEM;
983 }
984 
985 static void
986 atmci_submit_data(struct atmel_mci *host, struct mmc_data *data)
987 {
988 	return;
989 }
990 
991 /*
992  * Start PDC according to transfer direction.
993  */
994 static void
995 atmci_submit_data_pdc(struct atmel_mci *host, struct mmc_data *data)
996 {
997 	if (data->flags & MMC_DATA_READ)
998 		atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTEN);
999 	else
1000 		atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN);
1001 }
1002 
1003 static void
1004 atmci_submit_data_dma(struct atmel_mci *host, struct mmc_data *data)
1005 {
1006 	struct dma_chan			*chan = host->data_chan;
1007 	struct dma_async_tx_descriptor	*desc = host->dma.data_desc;
1008 
1009 	if (chan) {
1010 		dmaengine_submit(desc);
1011 		dma_async_issue_pending(chan);
1012 	}
1013 }
1014 
1015 static void atmci_stop_transfer(struct atmel_mci *host)
1016 {
1017 	dev_dbg(&host->pdev->dev,
1018 	        "(%s) set pending xfer complete\n", __func__);
1019 	atmci_set_pending(host, EVENT_XFER_COMPLETE);
1020 	atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1021 }
1022 
1023 /*
1024  * Stop data transfer because error(s) occured.
1025  */
1026 static void atmci_stop_transfer_pdc(struct atmel_mci *host)
1027 {
1028 	atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
1029 }
1030 
1031 static void atmci_stop_transfer_dma(struct atmel_mci *host)
1032 {
1033 	struct dma_chan *chan = host->data_chan;
1034 
1035 	if (chan) {
1036 		dmaengine_terminate_all(chan);
1037 		atmci_dma_cleanup(host);
1038 	} else {
1039 		/* Data transfer was stopped by the interrupt handler */
1040 		dev_dbg(&host->pdev->dev,
1041 		        "(%s) set pending xfer complete\n", __func__);
1042 		atmci_set_pending(host, EVENT_XFER_COMPLETE);
1043 		atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1044 	}
1045 }
1046 
1047 /*
1048  * Start a request: prepare data if needed, prepare the command and activate
1049  * interrupts.
1050  */
1051 static void atmci_start_request(struct atmel_mci *host,
1052 		struct atmel_mci_slot *slot)
1053 {
1054 	struct mmc_request	*mrq;
1055 	struct mmc_command	*cmd;
1056 	struct mmc_data		*data;
1057 	u32			iflags;
1058 	u32			cmdflags;
1059 
1060 	mrq = slot->mrq;
1061 	host->cur_slot = slot;
1062 	host->mrq = mrq;
1063 
1064 	host->pending_events = 0;
1065 	host->completed_events = 0;
1066 	host->cmd_status = 0;
1067 	host->data_status = 0;
1068 
1069 	dev_dbg(&host->pdev->dev, "start request: cmd %u\n", mrq->cmd->opcode);
1070 
1071 	if (host->need_reset || host->caps.need_reset_after_xfer) {
1072 		iflags = atmci_readl(host, ATMCI_IMR);
1073 		iflags &= (ATMCI_SDIOIRQA | ATMCI_SDIOIRQB);
1074 		atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
1075 		atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
1076 		atmci_writel(host, ATMCI_MR, host->mode_reg);
1077 		if (host->caps.has_cfg_reg)
1078 			atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1079 		atmci_writel(host, ATMCI_IER, iflags);
1080 		host->need_reset = false;
1081 	}
1082 	atmci_writel(host, ATMCI_SDCR, slot->sdc_reg);
1083 
1084 	iflags = atmci_readl(host, ATMCI_IMR);
1085 	if (iflags & ~(ATMCI_SDIOIRQA | ATMCI_SDIOIRQB))
1086 		dev_dbg(&slot->mmc->class_dev, "WARNING: IMR=0x%08x\n",
1087 				iflags);
1088 
1089 	if (unlikely(test_and_clear_bit(ATMCI_CARD_NEED_INIT, &slot->flags))) {
1090 		/* Send init sequence (74 clock cycles) */
1091 		atmci_writel(host, ATMCI_CMDR, ATMCI_CMDR_SPCMD_INIT);
1092 		while (!(atmci_readl(host, ATMCI_SR) & ATMCI_CMDRDY))
1093 			cpu_relax();
1094 	}
1095 	iflags = 0;
1096 	data = mrq->data;
1097 	if (data) {
1098 		atmci_set_timeout(host, slot, data);
1099 
1100 		/* Must set block count/size before sending command */
1101 		atmci_writel(host, ATMCI_BLKR, ATMCI_BCNT(data->blocks)
1102 				| ATMCI_BLKLEN(data->blksz));
1103 		dev_vdbg(&slot->mmc->class_dev, "BLKR=0x%08x\n",
1104 			ATMCI_BCNT(data->blocks) | ATMCI_BLKLEN(data->blksz));
1105 
1106 		iflags |= host->prepare_data(host, data);
1107 	}
1108 
1109 	iflags |= ATMCI_CMDRDY;
1110 	cmd = mrq->cmd;
1111 	cmdflags = atmci_prepare_command(slot->mmc, cmd);
1112 	atmci_send_command(host, cmd, cmdflags);
1113 
1114 	if (data)
1115 		host->submit_data(host, data);
1116 
1117 	if (mrq->stop) {
1118 		host->stop_cmdr = atmci_prepare_command(slot->mmc, mrq->stop);
1119 		host->stop_cmdr |= ATMCI_CMDR_STOP_XFER;
1120 		if (!(data->flags & MMC_DATA_WRITE))
1121 			host->stop_cmdr |= ATMCI_CMDR_TRDIR_READ;
1122 		if (data->flags & MMC_DATA_STREAM)
1123 			host->stop_cmdr |= ATMCI_CMDR_STREAM;
1124 		else
1125 			host->stop_cmdr |= ATMCI_CMDR_MULTI_BLOCK;
1126 	}
1127 
1128 	/*
1129 	 * We could have enabled interrupts earlier, but I suspect
1130 	 * that would open up a nice can of interesting race
1131 	 * conditions (e.g. command and data complete, but stop not
1132 	 * prepared yet.)
1133 	 */
1134 	atmci_writel(host, ATMCI_IER, iflags);
1135 
1136 	mod_timer(&host->timer, jiffies +  msecs_to_jiffies(2000));
1137 }
1138 
1139 static void atmci_queue_request(struct atmel_mci *host,
1140 		struct atmel_mci_slot *slot, struct mmc_request *mrq)
1141 {
1142 	dev_vdbg(&slot->mmc->class_dev, "queue request: state=%d\n",
1143 			host->state);
1144 
1145 	spin_lock_bh(&host->lock);
1146 	slot->mrq = mrq;
1147 	if (host->state == STATE_IDLE) {
1148 		host->state = STATE_SENDING_CMD;
1149 		atmci_start_request(host, slot);
1150 	} else {
1151 		dev_dbg(&host->pdev->dev, "queue request\n");
1152 		list_add_tail(&slot->queue_node, &host->queue);
1153 	}
1154 	spin_unlock_bh(&host->lock);
1155 }
1156 
1157 static void atmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
1158 {
1159 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1160 	struct atmel_mci	*host = slot->host;
1161 	struct mmc_data		*data;
1162 
1163 	WARN_ON(slot->mrq);
1164 	dev_dbg(&host->pdev->dev, "MRQ: cmd %u\n", mrq->cmd->opcode);
1165 
1166 	/*
1167 	 * We may "know" the card is gone even though there's still an
1168 	 * electrical connection. If so, we really need to communicate
1169 	 * this to the MMC core since there won't be any more
1170 	 * interrupts as the card is completely removed. Otherwise,
1171 	 * the MMC core might believe the card is still there even
1172 	 * though the card was just removed very slowly.
1173 	 */
1174 	if (!test_bit(ATMCI_CARD_PRESENT, &slot->flags)) {
1175 		mrq->cmd->error = -ENOMEDIUM;
1176 		mmc_request_done(mmc, mrq);
1177 		return;
1178 	}
1179 
1180 	/* We don't support multiple blocks of weird lengths. */
1181 	data = mrq->data;
1182 	if (data && data->blocks > 1 && data->blksz & 3) {
1183 		mrq->cmd->error = -EINVAL;
1184 		mmc_request_done(mmc, mrq);
1185 	}
1186 
1187 	atmci_queue_request(host, slot, mrq);
1188 }
1189 
1190 static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
1191 {
1192 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1193 	struct atmel_mci	*host = slot->host;
1194 	unsigned int		i;
1195 
1196 	slot->sdc_reg &= ~ATMCI_SDCBUS_MASK;
1197 	switch (ios->bus_width) {
1198 	case MMC_BUS_WIDTH_1:
1199 		slot->sdc_reg |= ATMCI_SDCBUS_1BIT;
1200 		break;
1201 	case MMC_BUS_WIDTH_4:
1202 		slot->sdc_reg |= ATMCI_SDCBUS_4BIT;
1203 		break;
1204 	}
1205 
1206 	if (ios->clock) {
1207 		unsigned int clock_min = ~0U;
1208 		u32 clkdiv;
1209 
1210 		spin_lock_bh(&host->lock);
1211 		if (!host->mode_reg) {
1212 			clk_enable(host->mck);
1213 			atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
1214 			atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
1215 			if (host->caps.has_cfg_reg)
1216 				atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1217 		}
1218 
1219 		/*
1220 		 * Use mirror of ios->clock to prevent race with mmc
1221 		 * core ios update when finding the minimum.
1222 		 */
1223 		slot->clock = ios->clock;
1224 		for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
1225 			if (host->slot[i] && host->slot[i]->clock
1226 					&& host->slot[i]->clock < clock_min)
1227 				clock_min = host->slot[i]->clock;
1228 		}
1229 
1230 		/* Calculate clock divider */
1231 		if (host->caps.has_odd_clk_div) {
1232 			clkdiv = DIV_ROUND_UP(host->bus_hz, clock_min) - 2;
1233 			if (clkdiv > 511) {
1234 				dev_warn(&mmc->class_dev,
1235 				         "clock %u too slow; using %lu\n",
1236 				         clock_min, host->bus_hz / (511 + 2));
1237 				clkdiv = 511;
1238 			}
1239 			host->mode_reg = ATMCI_MR_CLKDIV(clkdiv >> 1)
1240 			                 | ATMCI_MR_CLKODD(clkdiv & 1);
1241 		} else {
1242 			clkdiv = DIV_ROUND_UP(host->bus_hz, 2 * clock_min) - 1;
1243 			if (clkdiv > 255) {
1244 				dev_warn(&mmc->class_dev,
1245 				         "clock %u too slow; using %lu\n",
1246 				         clock_min, host->bus_hz / (2 * 256));
1247 				clkdiv = 255;
1248 			}
1249 			host->mode_reg = ATMCI_MR_CLKDIV(clkdiv);
1250 		}
1251 
1252 		/*
1253 		 * WRPROOF and RDPROOF prevent overruns/underruns by
1254 		 * stopping the clock when the FIFO is full/empty.
1255 		 * This state is not expected to last for long.
1256 		 */
1257 		if (host->caps.has_rwproof)
1258 			host->mode_reg |= (ATMCI_MR_WRPROOF | ATMCI_MR_RDPROOF);
1259 
1260 		if (host->caps.has_cfg_reg) {
1261 			/* setup High Speed mode in relation with card capacity */
1262 			if (ios->timing == MMC_TIMING_SD_HS)
1263 				host->cfg_reg |= ATMCI_CFG_HSMODE;
1264 			else
1265 				host->cfg_reg &= ~ATMCI_CFG_HSMODE;
1266 		}
1267 
1268 		if (list_empty(&host->queue)) {
1269 			atmci_writel(host, ATMCI_MR, host->mode_reg);
1270 			if (host->caps.has_cfg_reg)
1271 				atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1272 		} else {
1273 			host->need_clock_update = true;
1274 		}
1275 
1276 		spin_unlock_bh(&host->lock);
1277 	} else {
1278 		bool any_slot_active = false;
1279 
1280 		spin_lock_bh(&host->lock);
1281 		slot->clock = 0;
1282 		for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
1283 			if (host->slot[i] && host->slot[i]->clock) {
1284 				any_slot_active = true;
1285 				break;
1286 			}
1287 		}
1288 		if (!any_slot_active) {
1289 			atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIDIS);
1290 			if (host->mode_reg) {
1291 				atmci_readl(host, ATMCI_MR);
1292 				clk_disable(host->mck);
1293 			}
1294 			host->mode_reg = 0;
1295 		}
1296 		spin_unlock_bh(&host->lock);
1297 	}
1298 
1299 	switch (ios->power_mode) {
1300 	case MMC_POWER_UP:
1301 		set_bit(ATMCI_CARD_NEED_INIT, &slot->flags);
1302 		break;
1303 	default:
1304 		/*
1305 		 * TODO: None of the currently available AVR32-based
1306 		 * boards allow MMC power to be turned off. Implement
1307 		 * power control when this can be tested properly.
1308 		 *
1309 		 * We also need to hook this into the clock management
1310 		 * somehow so that newly inserted cards aren't
1311 		 * subjected to a fast clock before we have a chance
1312 		 * to figure out what the maximum rate is. Currently,
1313 		 * there's no way to avoid this, and there never will
1314 		 * be for boards that don't support power control.
1315 		 */
1316 		break;
1317 	}
1318 }
1319 
1320 static int atmci_get_ro(struct mmc_host *mmc)
1321 {
1322 	int			read_only = -ENOSYS;
1323 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1324 
1325 	if (gpio_is_valid(slot->wp_pin)) {
1326 		read_only = gpio_get_value(slot->wp_pin);
1327 		dev_dbg(&mmc->class_dev, "card is %s\n",
1328 				read_only ? "read-only" : "read-write");
1329 	}
1330 
1331 	return read_only;
1332 }
1333 
1334 static int atmci_get_cd(struct mmc_host *mmc)
1335 {
1336 	int			present = -ENOSYS;
1337 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1338 
1339 	if (gpio_is_valid(slot->detect_pin)) {
1340 		present = !(gpio_get_value(slot->detect_pin) ^
1341 			    slot->detect_is_active_high);
1342 		dev_dbg(&mmc->class_dev, "card is %spresent\n",
1343 				present ? "" : "not ");
1344 	}
1345 
1346 	return present;
1347 }
1348 
1349 static void atmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
1350 {
1351 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1352 	struct atmel_mci	*host = slot->host;
1353 
1354 	if (enable)
1355 		atmci_writel(host, ATMCI_IER, slot->sdio_irq);
1356 	else
1357 		atmci_writel(host, ATMCI_IDR, slot->sdio_irq);
1358 }
1359 
1360 static const struct mmc_host_ops atmci_ops = {
1361 	.request	= atmci_request,
1362 	.set_ios	= atmci_set_ios,
1363 	.get_ro		= atmci_get_ro,
1364 	.get_cd		= atmci_get_cd,
1365 	.enable_sdio_irq = atmci_enable_sdio_irq,
1366 };
1367 
1368 /* Called with host->lock held */
1369 static void atmci_request_end(struct atmel_mci *host, struct mmc_request *mrq)
1370 	__releases(&host->lock)
1371 	__acquires(&host->lock)
1372 {
1373 	struct atmel_mci_slot	*slot = NULL;
1374 	struct mmc_host		*prev_mmc = host->cur_slot->mmc;
1375 
1376 	WARN_ON(host->cmd || host->data);
1377 
1378 	/*
1379 	 * Update the MMC clock rate if necessary. This may be
1380 	 * necessary if set_ios() is called when a different slot is
1381 	 * busy transferring data.
1382 	 */
1383 	if (host->need_clock_update) {
1384 		atmci_writel(host, ATMCI_MR, host->mode_reg);
1385 		if (host->caps.has_cfg_reg)
1386 			atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1387 	}
1388 
1389 	host->cur_slot->mrq = NULL;
1390 	host->mrq = NULL;
1391 	if (!list_empty(&host->queue)) {
1392 		slot = list_entry(host->queue.next,
1393 				struct atmel_mci_slot, queue_node);
1394 		list_del(&slot->queue_node);
1395 		dev_vdbg(&host->pdev->dev, "list not empty: %s is next\n",
1396 				mmc_hostname(slot->mmc));
1397 		host->state = STATE_SENDING_CMD;
1398 		atmci_start_request(host, slot);
1399 	} else {
1400 		dev_vdbg(&host->pdev->dev, "list empty\n");
1401 		host->state = STATE_IDLE;
1402 	}
1403 
1404 	del_timer(&host->timer);
1405 
1406 	spin_unlock(&host->lock);
1407 	mmc_request_done(prev_mmc, mrq);
1408 	spin_lock(&host->lock);
1409 }
1410 
1411 static void atmci_command_complete(struct atmel_mci *host,
1412 			struct mmc_command *cmd)
1413 {
1414 	u32		status = host->cmd_status;
1415 
1416 	/* Read the response from the card (up to 16 bytes) */
1417 	cmd->resp[0] = atmci_readl(host, ATMCI_RSPR);
1418 	cmd->resp[1] = atmci_readl(host, ATMCI_RSPR);
1419 	cmd->resp[2] = atmci_readl(host, ATMCI_RSPR);
1420 	cmd->resp[3] = atmci_readl(host, ATMCI_RSPR);
1421 
1422 	if (status & ATMCI_RTOE)
1423 		cmd->error = -ETIMEDOUT;
1424 	else if ((cmd->flags & MMC_RSP_CRC) && (status & ATMCI_RCRCE))
1425 		cmd->error = -EILSEQ;
1426 	else if (status & (ATMCI_RINDE | ATMCI_RDIRE | ATMCI_RENDE))
1427 		cmd->error = -EIO;
1428 	else if (host->mrq->data && (host->mrq->data->blksz & 3)) {
1429 		if (host->caps.need_blksz_mul_4) {
1430 			cmd->error = -EINVAL;
1431 			host->need_reset = 1;
1432 		}
1433 	} else
1434 		cmd->error = 0;
1435 }
1436 
1437 static void atmci_detect_change(unsigned long data)
1438 {
1439 	struct atmel_mci_slot	*slot = (struct atmel_mci_slot *)data;
1440 	bool			present;
1441 	bool			present_old;
1442 
1443 	/*
1444 	 * atmci_cleanup_slot() sets the ATMCI_SHUTDOWN flag before
1445 	 * freeing the interrupt. We must not re-enable the interrupt
1446 	 * if it has been freed, and if we're shutting down, it
1447 	 * doesn't really matter whether the card is present or not.
1448 	 */
1449 	smp_rmb();
1450 	if (test_bit(ATMCI_SHUTDOWN, &slot->flags))
1451 		return;
1452 
1453 	enable_irq(gpio_to_irq(slot->detect_pin));
1454 	present = !(gpio_get_value(slot->detect_pin) ^
1455 		    slot->detect_is_active_high);
1456 	present_old = test_bit(ATMCI_CARD_PRESENT, &slot->flags);
1457 
1458 	dev_vdbg(&slot->mmc->class_dev, "detect change: %d (was %d)\n",
1459 			present, present_old);
1460 
1461 	if (present != present_old) {
1462 		struct atmel_mci	*host = slot->host;
1463 		struct mmc_request	*mrq;
1464 
1465 		dev_dbg(&slot->mmc->class_dev, "card %s\n",
1466 			present ? "inserted" : "removed");
1467 
1468 		spin_lock(&host->lock);
1469 
1470 		if (!present)
1471 			clear_bit(ATMCI_CARD_PRESENT, &slot->flags);
1472 		else
1473 			set_bit(ATMCI_CARD_PRESENT, &slot->flags);
1474 
1475 		/* Clean up queue if present */
1476 		mrq = slot->mrq;
1477 		if (mrq) {
1478 			if (mrq == host->mrq) {
1479 				/*
1480 				 * Reset controller to terminate any ongoing
1481 				 * commands or data transfers.
1482 				 */
1483 				atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
1484 				atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
1485 				atmci_writel(host, ATMCI_MR, host->mode_reg);
1486 				if (host->caps.has_cfg_reg)
1487 					atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1488 
1489 				host->data = NULL;
1490 				host->cmd = NULL;
1491 
1492 				switch (host->state) {
1493 				case STATE_IDLE:
1494 					break;
1495 				case STATE_SENDING_CMD:
1496 					mrq->cmd->error = -ENOMEDIUM;
1497 					if (mrq->data)
1498 						host->stop_transfer(host);
1499 					break;
1500 				case STATE_DATA_XFER:
1501 					mrq->data->error = -ENOMEDIUM;
1502 					host->stop_transfer(host);
1503 					break;
1504 				case STATE_WAITING_NOTBUSY:
1505 					mrq->data->error = -ENOMEDIUM;
1506 					break;
1507 				case STATE_SENDING_STOP:
1508 					mrq->stop->error = -ENOMEDIUM;
1509 					break;
1510 				case STATE_END_REQUEST:
1511 					break;
1512 				}
1513 
1514 				atmci_request_end(host, mrq);
1515 			} else {
1516 				list_del(&slot->queue_node);
1517 				mrq->cmd->error = -ENOMEDIUM;
1518 				if (mrq->data)
1519 					mrq->data->error = -ENOMEDIUM;
1520 				if (mrq->stop)
1521 					mrq->stop->error = -ENOMEDIUM;
1522 
1523 				spin_unlock(&host->lock);
1524 				mmc_request_done(slot->mmc, mrq);
1525 				spin_lock(&host->lock);
1526 			}
1527 		}
1528 		spin_unlock(&host->lock);
1529 
1530 		mmc_detect_change(slot->mmc, 0);
1531 	}
1532 }
1533 
1534 static void atmci_tasklet_func(unsigned long priv)
1535 {
1536 	struct atmel_mci	*host = (struct atmel_mci *)priv;
1537 	struct mmc_request	*mrq = host->mrq;
1538 	struct mmc_data		*data = host->data;
1539 	enum atmel_mci_state	state = host->state;
1540 	enum atmel_mci_state	prev_state;
1541 	u32			status;
1542 
1543 	spin_lock(&host->lock);
1544 
1545 	state = host->state;
1546 
1547 	dev_vdbg(&host->pdev->dev,
1548 		"tasklet: state %u pending/completed/mask %lx/%lx/%x\n",
1549 		state, host->pending_events, host->completed_events,
1550 		atmci_readl(host, ATMCI_IMR));
1551 
1552 	do {
1553 		prev_state = state;
1554 		dev_dbg(&host->pdev->dev, "FSM: state=%d\n", state);
1555 
1556 		switch (state) {
1557 		case STATE_IDLE:
1558 			break;
1559 
1560 		case STATE_SENDING_CMD:
1561 			/*
1562 			 * Command has been sent, we are waiting for command
1563 			 * ready. Then we have three next states possible:
1564 			 * END_REQUEST by default, WAITING_NOTBUSY if it's a
1565 			 * command needing it or DATA_XFER if there is data.
1566 			 */
1567 			dev_dbg(&host->pdev->dev, "FSM: cmd ready?\n");
1568 			if (!atmci_test_and_clear_pending(host,
1569 						EVENT_CMD_RDY))
1570 				break;
1571 
1572 			dev_dbg(&host->pdev->dev, "set completed cmd ready\n");
1573 			host->cmd = NULL;
1574 			atmci_set_completed(host, EVENT_CMD_RDY);
1575 			atmci_command_complete(host, mrq->cmd);
1576 			if (mrq->data) {
1577 				dev_dbg(&host->pdev->dev,
1578 				        "command with data transfer");
1579 				/*
1580 				 * If there is a command error don't start
1581 				 * data transfer.
1582 				 */
1583 				if (mrq->cmd->error) {
1584 					host->stop_transfer(host);
1585 					host->data = NULL;
1586 					atmci_writel(host, ATMCI_IDR,
1587 					             ATMCI_TXRDY | ATMCI_RXRDY
1588 					             | ATMCI_DATA_ERROR_FLAGS);
1589 					state = STATE_END_REQUEST;
1590 				} else
1591 					state = STATE_DATA_XFER;
1592 			} else if ((!mrq->data) && (mrq->cmd->flags & MMC_RSP_BUSY)) {
1593 				dev_dbg(&host->pdev->dev,
1594 				        "command response need waiting notbusy");
1595 				atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1596 				state = STATE_WAITING_NOTBUSY;
1597 			} else
1598 				state = STATE_END_REQUEST;
1599 
1600 			break;
1601 
1602 		case STATE_DATA_XFER:
1603 			if (atmci_test_and_clear_pending(host,
1604 						EVENT_DATA_ERROR)) {
1605 				dev_dbg(&host->pdev->dev, "set completed data error\n");
1606 				atmci_set_completed(host, EVENT_DATA_ERROR);
1607 				state = STATE_END_REQUEST;
1608 				break;
1609 			}
1610 
1611 			/*
1612 			 * A data transfer is in progress. The event expected
1613 			 * to move to the next state depends of data transfer
1614 			 * type (PDC or DMA). Once transfer done we can move
1615 			 * to the next step which is WAITING_NOTBUSY in write
1616 			 * case and directly SENDING_STOP in read case.
1617 			 */
1618 			dev_dbg(&host->pdev->dev, "FSM: xfer complete?\n");
1619 			if (!atmci_test_and_clear_pending(host,
1620 						EVENT_XFER_COMPLETE))
1621 				break;
1622 
1623 			dev_dbg(&host->pdev->dev,
1624 			        "(%s) set completed xfer complete\n",
1625 				__func__);
1626 			atmci_set_completed(host, EVENT_XFER_COMPLETE);
1627 
1628 			if (host->data->flags & MMC_DATA_WRITE) {
1629 				atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1630 				state = STATE_WAITING_NOTBUSY;
1631 			} else if (host->mrq->stop) {
1632 				atmci_writel(host, ATMCI_IER, ATMCI_CMDRDY);
1633 				atmci_send_stop_cmd(host, data);
1634 				state = STATE_SENDING_STOP;
1635 			} else {
1636 				host->data = NULL;
1637 				data->bytes_xfered = data->blocks * data->blksz;
1638 				data->error = 0;
1639 				state = STATE_END_REQUEST;
1640 			}
1641 			break;
1642 
1643 		case STATE_WAITING_NOTBUSY:
1644 			/*
1645 			 * We can be in the state for two reasons: a command
1646 			 * requiring waiting not busy signal (stop command
1647 			 * included) or a write operation. In the latest case,
1648 			 * we need to send a stop command.
1649 			 */
1650 			dev_dbg(&host->pdev->dev, "FSM: not busy?\n");
1651 			if (!atmci_test_and_clear_pending(host,
1652 						EVENT_NOTBUSY))
1653 				break;
1654 
1655 			dev_dbg(&host->pdev->dev, "set completed not busy\n");
1656 			atmci_set_completed(host, EVENT_NOTBUSY);
1657 
1658 			if (host->data) {
1659 				/*
1660 				 * For some commands such as CMD53, even if
1661 				 * there is data transfer, there is no stop
1662 				 * command to send.
1663 				 */
1664 				if (host->mrq->stop) {
1665 					atmci_writel(host, ATMCI_IER,
1666 					             ATMCI_CMDRDY);
1667 					atmci_send_stop_cmd(host, data);
1668 					state = STATE_SENDING_STOP;
1669 				} else {
1670 					host->data = NULL;
1671 					data->bytes_xfered = data->blocks
1672 					                     * data->blksz;
1673 					data->error = 0;
1674 					state = STATE_END_REQUEST;
1675 				}
1676 			} else
1677 				state = STATE_END_REQUEST;
1678 			break;
1679 
1680 		case STATE_SENDING_STOP:
1681 			/*
1682 			 * In this state, it is important to set host->data to
1683 			 * NULL (which is tested in the waiting notbusy state)
1684 			 * in order to go to the end request state instead of
1685 			 * sending stop again.
1686 			 */
1687 			dev_dbg(&host->pdev->dev, "FSM: cmd ready?\n");
1688 			if (!atmci_test_and_clear_pending(host,
1689 						EVENT_CMD_RDY))
1690 				break;
1691 
1692 			dev_dbg(&host->pdev->dev, "FSM: cmd ready\n");
1693 			host->cmd = NULL;
1694 			data->bytes_xfered = data->blocks * data->blksz;
1695 			data->error = 0;
1696 			atmci_command_complete(host, mrq->stop);
1697 			if (mrq->stop->error) {
1698 				host->stop_transfer(host);
1699 				atmci_writel(host, ATMCI_IDR,
1700 				             ATMCI_TXRDY | ATMCI_RXRDY
1701 				             | ATMCI_DATA_ERROR_FLAGS);
1702 				state = STATE_END_REQUEST;
1703 			} else {
1704 				atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1705 				state = STATE_WAITING_NOTBUSY;
1706 			}
1707 			host->data = NULL;
1708 			break;
1709 
1710 		case STATE_END_REQUEST:
1711 			atmci_writel(host, ATMCI_IDR, ATMCI_TXRDY | ATMCI_RXRDY
1712 			                   | ATMCI_DATA_ERROR_FLAGS);
1713 			status = host->data_status;
1714 			if (unlikely(status)) {
1715 				host->stop_transfer(host);
1716 				host->data = NULL;
1717 				if (status & ATMCI_DTOE) {
1718 					data->error = -ETIMEDOUT;
1719 				} else if (status & ATMCI_DCRCE) {
1720 					data->error = -EILSEQ;
1721 				} else {
1722 					data->error = -EIO;
1723 				}
1724 			}
1725 
1726 			atmci_request_end(host, host->mrq);
1727 			state = STATE_IDLE;
1728 			break;
1729 		}
1730 	} while (state != prev_state);
1731 
1732 	host->state = state;
1733 
1734 	spin_unlock(&host->lock);
1735 }
1736 
1737 static void atmci_read_data_pio(struct atmel_mci *host)
1738 {
1739 	struct scatterlist	*sg = host->sg;
1740 	void			*buf = sg_virt(sg);
1741 	unsigned int		offset = host->pio_offset;
1742 	struct mmc_data		*data = host->data;
1743 	u32			value;
1744 	u32			status;
1745 	unsigned int		nbytes = 0;
1746 
1747 	do {
1748 		value = atmci_readl(host, ATMCI_RDR);
1749 		if (likely(offset + 4 <= sg->length)) {
1750 			put_unaligned(value, (u32 *)(buf + offset));
1751 
1752 			offset += 4;
1753 			nbytes += 4;
1754 
1755 			if (offset == sg->length) {
1756 				flush_dcache_page(sg_page(sg));
1757 				host->sg = sg = sg_next(sg);
1758 				if (!sg)
1759 					goto done;
1760 
1761 				offset = 0;
1762 				buf = sg_virt(sg);
1763 			}
1764 		} else {
1765 			unsigned int remaining = sg->length - offset;
1766 			memcpy(buf + offset, &value, remaining);
1767 			nbytes += remaining;
1768 
1769 			flush_dcache_page(sg_page(sg));
1770 			host->sg = sg = sg_next(sg);
1771 			if (!sg)
1772 				goto done;
1773 
1774 			offset = 4 - remaining;
1775 			buf = sg_virt(sg);
1776 			memcpy(buf, (u8 *)&value + remaining, offset);
1777 			nbytes += offset;
1778 		}
1779 
1780 		status = atmci_readl(host, ATMCI_SR);
1781 		if (status & ATMCI_DATA_ERROR_FLAGS) {
1782 			atmci_writel(host, ATMCI_IDR, (ATMCI_NOTBUSY | ATMCI_RXRDY
1783 						| ATMCI_DATA_ERROR_FLAGS));
1784 			host->data_status = status;
1785 			data->bytes_xfered += nbytes;
1786 			return;
1787 		}
1788 	} while (status & ATMCI_RXRDY);
1789 
1790 	host->pio_offset = offset;
1791 	data->bytes_xfered += nbytes;
1792 
1793 	return;
1794 
1795 done:
1796 	atmci_writel(host, ATMCI_IDR, ATMCI_RXRDY);
1797 	atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1798 	data->bytes_xfered += nbytes;
1799 	smp_wmb();
1800 	atmci_set_pending(host, EVENT_XFER_COMPLETE);
1801 }
1802 
1803 static void atmci_write_data_pio(struct atmel_mci *host)
1804 {
1805 	struct scatterlist	*sg = host->sg;
1806 	void			*buf = sg_virt(sg);
1807 	unsigned int		offset = host->pio_offset;
1808 	struct mmc_data		*data = host->data;
1809 	u32			value;
1810 	u32			status;
1811 	unsigned int		nbytes = 0;
1812 
1813 	do {
1814 		if (likely(offset + 4 <= sg->length)) {
1815 			value = get_unaligned((u32 *)(buf + offset));
1816 			atmci_writel(host, ATMCI_TDR, value);
1817 
1818 			offset += 4;
1819 			nbytes += 4;
1820 			if (offset == sg->length) {
1821 				host->sg = sg = sg_next(sg);
1822 				if (!sg)
1823 					goto done;
1824 
1825 				offset = 0;
1826 				buf = sg_virt(sg);
1827 			}
1828 		} else {
1829 			unsigned int remaining = sg->length - offset;
1830 
1831 			value = 0;
1832 			memcpy(&value, buf + offset, remaining);
1833 			nbytes += remaining;
1834 
1835 			host->sg = sg = sg_next(sg);
1836 			if (!sg) {
1837 				atmci_writel(host, ATMCI_TDR, value);
1838 				goto done;
1839 			}
1840 
1841 			offset = 4 - remaining;
1842 			buf = sg_virt(sg);
1843 			memcpy((u8 *)&value + remaining, buf, offset);
1844 			atmci_writel(host, ATMCI_TDR, value);
1845 			nbytes += offset;
1846 		}
1847 
1848 		status = atmci_readl(host, ATMCI_SR);
1849 		if (status & ATMCI_DATA_ERROR_FLAGS) {
1850 			atmci_writel(host, ATMCI_IDR, (ATMCI_NOTBUSY | ATMCI_TXRDY
1851 						| ATMCI_DATA_ERROR_FLAGS));
1852 			host->data_status = status;
1853 			data->bytes_xfered += nbytes;
1854 			return;
1855 		}
1856 	} while (status & ATMCI_TXRDY);
1857 
1858 	host->pio_offset = offset;
1859 	data->bytes_xfered += nbytes;
1860 
1861 	return;
1862 
1863 done:
1864 	atmci_writel(host, ATMCI_IDR, ATMCI_TXRDY);
1865 	atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1866 	data->bytes_xfered += nbytes;
1867 	smp_wmb();
1868 	atmci_set_pending(host, EVENT_XFER_COMPLETE);
1869 }
1870 
1871 static void atmci_sdio_interrupt(struct atmel_mci *host, u32 status)
1872 {
1873 	int	i;
1874 
1875 	for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
1876 		struct atmel_mci_slot *slot = host->slot[i];
1877 		if (slot && (status & slot->sdio_irq)) {
1878 			mmc_signal_sdio_irq(slot->mmc);
1879 		}
1880 	}
1881 }
1882 
1883 
1884 static irqreturn_t atmci_interrupt(int irq, void *dev_id)
1885 {
1886 	struct atmel_mci	*host = dev_id;
1887 	u32			status, mask, pending;
1888 	unsigned int		pass_count = 0;
1889 
1890 	do {
1891 		status = atmci_readl(host, ATMCI_SR);
1892 		mask = atmci_readl(host, ATMCI_IMR);
1893 		pending = status & mask;
1894 		if (!pending)
1895 			break;
1896 
1897 		if (pending & ATMCI_DATA_ERROR_FLAGS) {
1898 			dev_dbg(&host->pdev->dev, "IRQ: data error\n");
1899 			atmci_writel(host, ATMCI_IDR, ATMCI_DATA_ERROR_FLAGS
1900 					| ATMCI_RXRDY | ATMCI_TXRDY
1901 					| ATMCI_ENDRX | ATMCI_ENDTX
1902 					| ATMCI_RXBUFF | ATMCI_TXBUFE);
1903 
1904 			host->data_status = status;
1905 			dev_dbg(&host->pdev->dev, "set pending data error\n");
1906 			smp_wmb();
1907 			atmci_set_pending(host, EVENT_DATA_ERROR);
1908 			tasklet_schedule(&host->tasklet);
1909 		}
1910 
1911 		if (pending & ATMCI_TXBUFE) {
1912 			dev_dbg(&host->pdev->dev, "IRQ: tx buffer empty\n");
1913 			atmci_writel(host, ATMCI_IDR, ATMCI_TXBUFE);
1914 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDTX);
1915 			/*
1916 			 * We can receive this interruption before having configured
1917 			 * the second pdc buffer, so we need to reconfigure first and
1918 			 * second buffers again
1919 			 */
1920 			if (host->data_size) {
1921 				atmci_pdc_set_both_buf(host, XFER_TRANSMIT);
1922 				atmci_writel(host, ATMCI_IER, ATMCI_ENDTX);
1923 				atmci_writel(host, ATMCI_IER, ATMCI_TXBUFE);
1924 			} else {
1925 				atmci_pdc_complete(host);
1926 			}
1927 		} else if (pending & ATMCI_ENDTX) {
1928 			dev_dbg(&host->pdev->dev, "IRQ: end of tx buffer\n");
1929 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDTX);
1930 
1931 			if (host->data_size) {
1932 				atmci_pdc_set_single_buf(host,
1933 						XFER_TRANSMIT, PDC_SECOND_BUF);
1934 				atmci_writel(host, ATMCI_IER, ATMCI_ENDTX);
1935 			}
1936 		}
1937 
1938 		if (pending & ATMCI_RXBUFF) {
1939 			dev_dbg(&host->pdev->dev, "IRQ: rx buffer full\n");
1940 			atmci_writel(host, ATMCI_IDR, ATMCI_RXBUFF);
1941 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDRX);
1942 			/*
1943 			 * We can receive this interruption before having configured
1944 			 * the second pdc buffer, so we need to reconfigure first and
1945 			 * second buffers again
1946 			 */
1947 			if (host->data_size) {
1948 				atmci_pdc_set_both_buf(host, XFER_RECEIVE);
1949 				atmci_writel(host, ATMCI_IER, ATMCI_ENDRX);
1950 				atmci_writel(host, ATMCI_IER, ATMCI_RXBUFF);
1951 			} else {
1952 				atmci_pdc_complete(host);
1953 			}
1954 		} else if (pending & ATMCI_ENDRX) {
1955 			dev_dbg(&host->pdev->dev, "IRQ: end of rx buffer\n");
1956 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDRX);
1957 
1958 			if (host->data_size) {
1959 				atmci_pdc_set_single_buf(host,
1960 						XFER_RECEIVE, PDC_SECOND_BUF);
1961 				atmci_writel(host, ATMCI_IER, ATMCI_ENDRX);
1962 			}
1963 		}
1964 
1965 		/*
1966 		 * First mci IPs, so mainly the ones having pdc, have some
1967 		 * issues with the notbusy signal. You can't get it after
1968 		 * data transmission if you have not sent a stop command.
1969 		 * The appropriate workaround is to use the BLKE signal.
1970 		 */
1971 		if (pending & ATMCI_BLKE) {
1972 			dev_dbg(&host->pdev->dev, "IRQ: blke\n");
1973 			atmci_writel(host, ATMCI_IDR, ATMCI_BLKE);
1974 			smp_wmb();
1975 			dev_dbg(&host->pdev->dev, "set pending notbusy\n");
1976 			atmci_set_pending(host, EVENT_NOTBUSY);
1977 			tasklet_schedule(&host->tasklet);
1978 		}
1979 
1980 		if (pending & ATMCI_NOTBUSY) {
1981 			dev_dbg(&host->pdev->dev, "IRQ: not_busy\n");
1982 			atmci_writel(host, ATMCI_IDR, ATMCI_NOTBUSY);
1983 			smp_wmb();
1984 			dev_dbg(&host->pdev->dev, "set pending notbusy\n");
1985 			atmci_set_pending(host, EVENT_NOTBUSY);
1986 			tasklet_schedule(&host->tasklet);
1987 		}
1988 
1989 		if (pending & ATMCI_RXRDY)
1990 			atmci_read_data_pio(host);
1991 		if (pending & ATMCI_TXRDY)
1992 			atmci_write_data_pio(host);
1993 
1994 		if (pending & ATMCI_CMDRDY) {
1995 			dev_dbg(&host->pdev->dev, "IRQ: cmd ready\n");
1996 			atmci_writel(host, ATMCI_IDR, ATMCI_CMDRDY);
1997 			host->cmd_status = status;
1998 			smp_wmb();
1999 			dev_dbg(&host->pdev->dev, "set pending cmd rdy\n");
2000 			atmci_set_pending(host, EVENT_CMD_RDY);
2001 			tasklet_schedule(&host->tasklet);
2002 		}
2003 
2004 		if (pending & (ATMCI_SDIOIRQA | ATMCI_SDIOIRQB))
2005 			atmci_sdio_interrupt(host, status);
2006 
2007 	} while (pass_count++ < 5);
2008 
2009 	return pass_count ? IRQ_HANDLED : IRQ_NONE;
2010 }
2011 
2012 static irqreturn_t atmci_detect_interrupt(int irq, void *dev_id)
2013 {
2014 	struct atmel_mci_slot	*slot = dev_id;
2015 
2016 	/*
2017 	 * Disable interrupts until the pin has stabilized and check
2018 	 * the state then. Use mod_timer() since we may be in the
2019 	 * middle of the timer routine when this interrupt triggers.
2020 	 */
2021 	disable_irq_nosync(irq);
2022 	mod_timer(&slot->detect_timer, jiffies + msecs_to_jiffies(20));
2023 
2024 	return IRQ_HANDLED;
2025 }
2026 
2027 static int __init atmci_init_slot(struct atmel_mci *host,
2028 		struct mci_slot_pdata *slot_data, unsigned int id,
2029 		u32 sdc_reg, u32 sdio_irq)
2030 {
2031 	struct mmc_host			*mmc;
2032 	struct atmel_mci_slot		*slot;
2033 
2034 	mmc = mmc_alloc_host(sizeof(struct atmel_mci_slot), &host->pdev->dev);
2035 	if (!mmc)
2036 		return -ENOMEM;
2037 
2038 	slot = mmc_priv(mmc);
2039 	slot->mmc = mmc;
2040 	slot->host = host;
2041 	slot->detect_pin = slot_data->detect_pin;
2042 	slot->wp_pin = slot_data->wp_pin;
2043 	slot->detect_is_active_high = slot_data->detect_is_active_high;
2044 	slot->sdc_reg = sdc_reg;
2045 	slot->sdio_irq = sdio_irq;
2046 
2047 	mmc->ops = &atmci_ops;
2048 	mmc->f_min = DIV_ROUND_UP(host->bus_hz, 512);
2049 	mmc->f_max = host->bus_hz / 2;
2050 	mmc->ocr_avail	= MMC_VDD_32_33 | MMC_VDD_33_34;
2051 	if (sdio_irq)
2052 		mmc->caps |= MMC_CAP_SDIO_IRQ;
2053 	if (host->caps.has_highspeed)
2054 		mmc->caps |= MMC_CAP_SD_HIGHSPEED;
2055 	/*
2056 	 * Without the read/write proof capability, it is strongly suggested to
2057 	 * use only one bit for data to prevent fifo underruns and overruns
2058 	 * which will corrupt data.
2059 	 */
2060 	if ((slot_data->bus_width >= 4) && host->caps.has_rwproof)
2061 		mmc->caps |= MMC_CAP_4_BIT_DATA;
2062 
2063 	if (atmci_get_version(host) < 0x200) {
2064 		mmc->max_segs = 256;
2065 		mmc->max_blk_size = 4095;
2066 		mmc->max_blk_count = 256;
2067 		mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
2068 		mmc->max_seg_size = mmc->max_blk_size * mmc->max_segs;
2069 	} else {
2070 		mmc->max_segs = 64;
2071 		mmc->max_req_size = 32768 * 512;
2072 		mmc->max_blk_size = 32768;
2073 		mmc->max_blk_count = 512;
2074 	}
2075 
2076 	/* Assume card is present initially */
2077 	set_bit(ATMCI_CARD_PRESENT, &slot->flags);
2078 	if (gpio_is_valid(slot->detect_pin)) {
2079 		if (gpio_request(slot->detect_pin, "mmc_detect")) {
2080 			dev_dbg(&mmc->class_dev, "no detect pin available\n");
2081 			slot->detect_pin = -EBUSY;
2082 		} else if (gpio_get_value(slot->detect_pin) ^
2083 				slot->detect_is_active_high) {
2084 			clear_bit(ATMCI_CARD_PRESENT, &slot->flags);
2085 		}
2086 	}
2087 
2088 	if (!gpio_is_valid(slot->detect_pin))
2089 		mmc->caps |= MMC_CAP_NEEDS_POLL;
2090 
2091 	if (gpio_is_valid(slot->wp_pin)) {
2092 		if (gpio_request(slot->wp_pin, "mmc_wp")) {
2093 			dev_dbg(&mmc->class_dev, "no WP pin available\n");
2094 			slot->wp_pin = -EBUSY;
2095 		}
2096 	}
2097 
2098 	host->slot[id] = slot;
2099 	mmc_add_host(mmc);
2100 
2101 	if (gpio_is_valid(slot->detect_pin)) {
2102 		int ret;
2103 
2104 		setup_timer(&slot->detect_timer, atmci_detect_change,
2105 				(unsigned long)slot);
2106 
2107 		ret = request_irq(gpio_to_irq(slot->detect_pin),
2108 				atmci_detect_interrupt,
2109 				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
2110 				"mmc-detect", slot);
2111 		if (ret) {
2112 			dev_dbg(&mmc->class_dev,
2113 				"could not request IRQ %d for detect pin\n",
2114 				gpio_to_irq(slot->detect_pin));
2115 			gpio_free(slot->detect_pin);
2116 			slot->detect_pin = -EBUSY;
2117 		}
2118 	}
2119 
2120 	atmci_init_debugfs(slot);
2121 
2122 	return 0;
2123 }
2124 
2125 static void __exit atmci_cleanup_slot(struct atmel_mci_slot *slot,
2126 		unsigned int id)
2127 {
2128 	/* Debugfs stuff is cleaned up by mmc core */
2129 
2130 	set_bit(ATMCI_SHUTDOWN, &slot->flags);
2131 	smp_wmb();
2132 
2133 	mmc_remove_host(slot->mmc);
2134 
2135 	if (gpio_is_valid(slot->detect_pin)) {
2136 		int pin = slot->detect_pin;
2137 
2138 		free_irq(gpio_to_irq(pin), slot);
2139 		del_timer_sync(&slot->detect_timer);
2140 		gpio_free(pin);
2141 	}
2142 	if (gpio_is_valid(slot->wp_pin))
2143 		gpio_free(slot->wp_pin);
2144 
2145 	slot->host->slot[id] = NULL;
2146 	mmc_free_host(slot->mmc);
2147 }
2148 
2149 static bool atmci_filter(struct dma_chan *chan, void *slave)
2150 {
2151 	struct mci_dma_data	*sl = slave;
2152 
2153 	if (sl && find_slave_dev(sl) == chan->device->dev) {
2154 		chan->private = slave_data_ptr(sl);
2155 		return true;
2156 	} else {
2157 		return false;
2158 	}
2159 }
2160 
2161 static bool atmci_configure_dma(struct atmel_mci *host)
2162 {
2163 	struct mci_platform_data	*pdata;
2164 
2165 	if (host == NULL)
2166 		return false;
2167 
2168 	pdata = host->pdev->dev.platform_data;
2169 
2170 	if (pdata && find_slave_dev(pdata->dma_slave)) {
2171 		dma_cap_mask_t mask;
2172 
2173 		/* Try to grab a DMA channel */
2174 		dma_cap_zero(mask);
2175 		dma_cap_set(DMA_SLAVE, mask);
2176 		host->dma.chan =
2177 			dma_request_channel(mask, atmci_filter, pdata->dma_slave);
2178 	}
2179 	if (!host->dma.chan) {
2180 		dev_warn(&host->pdev->dev, "no DMA channel available\n");
2181 		return false;
2182 	} else {
2183 		dev_info(&host->pdev->dev,
2184 					"using %s for DMA transfers\n",
2185 					dma_chan_name(host->dma.chan));
2186 
2187 		host->dma_conf.src_addr = host->mapbase + ATMCI_RDR;
2188 		host->dma_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
2189 		host->dma_conf.src_maxburst = 1;
2190 		host->dma_conf.dst_addr = host->mapbase + ATMCI_TDR;
2191 		host->dma_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
2192 		host->dma_conf.dst_maxburst = 1;
2193 		host->dma_conf.device_fc = false;
2194 		return true;
2195 	}
2196 }
2197 
2198 /*
2199  * HSMCI (High Speed MCI) module is not fully compatible with MCI module.
2200  * HSMCI provides DMA support and a new config register but no more supports
2201  * PDC.
2202  */
2203 static void __init atmci_get_cap(struct atmel_mci *host)
2204 {
2205 	unsigned int version;
2206 
2207 	version = atmci_get_version(host);
2208 	dev_info(&host->pdev->dev,
2209 			"version: 0x%x\n", version);
2210 
2211 	host->caps.has_dma = 0;
2212 	host->caps.has_pdc = 1;
2213 	host->caps.has_cfg_reg = 0;
2214 	host->caps.has_cstor_reg = 0;
2215 	host->caps.has_highspeed = 0;
2216 	host->caps.has_rwproof = 0;
2217 	host->caps.has_odd_clk_div = 0;
2218 	host->caps.has_bad_data_ordering = 1;
2219 	host->caps.need_reset_after_xfer = 1;
2220 	host->caps.need_blksz_mul_4 = 1;
2221 
2222 	/* keep only major version number */
2223 	switch (version & 0xf00) {
2224 	case 0x500:
2225 		host->caps.has_odd_clk_div = 1;
2226 	case 0x400:
2227 	case 0x300:
2228 #ifdef CONFIG_AT_HDMAC
2229 		host->caps.has_dma = 1;
2230 #else
2231 		dev_info(&host->pdev->dev,
2232 			"has dma capability but dma engine is not selected, then use pio\n");
2233 #endif
2234 		host->caps.has_pdc = 0;
2235 		host->caps.has_cfg_reg = 1;
2236 		host->caps.has_cstor_reg = 1;
2237 		host->caps.has_highspeed = 1;
2238 	case 0x200:
2239 		host->caps.has_rwproof = 1;
2240 		host->caps.need_blksz_mul_4 = 0;
2241 	case 0x100:
2242 		host->caps.has_bad_data_ordering = 0;
2243 		host->caps.need_reset_after_xfer = 0;
2244 	case 0x0:
2245 		break;
2246 	default:
2247 		host->caps.has_pdc = 0;
2248 		dev_warn(&host->pdev->dev,
2249 				"Unmanaged mci version, set minimum capabilities\n");
2250 		break;
2251 	}
2252 }
2253 
2254 static int __init atmci_probe(struct platform_device *pdev)
2255 {
2256 	struct mci_platform_data	*pdata;
2257 	struct atmel_mci		*host;
2258 	struct resource			*regs;
2259 	unsigned int			nr_slots;
2260 	int				irq;
2261 	int				ret;
2262 
2263 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2264 	if (!regs)
2265 		return -ENXIO;
2266 	pdata = pdev->dev.platform_data;
2267 	if (!pdata)
2268 		return -ENXIO;
2269 	irq = platform_get_irq(pdev, 0);
2270 	if (irq < 0)
2271 		return irq;
2272 
2273 	host = kzalloc(sizeof(struct atmel_mci), GFP_KERNEL);
2274 	if (!host)
2275 		return -ENOMEM;
2276 
2277 	host->pdev = pdev;
2278 	spin_lock_init(&host->lock);
2279 	INIT_LIST_HEAD(&host->queue);
2280 
2281 	host->mck = clk_get(&pdev->dev, "mci_clk");
2282 	if (IS_ERR(host->mck)) {
2283 		ret = PTR_ERR(host->mck);
2284 		goto err_clk_get;
2285 	}
2286 
2287 	ret = -ENOMEM;
2288 	host->regs = ioremap(regs->start, resource_size(regs));
2289 	if (!host->regs)
2290 		goto err_ioremap;
2291 
2292 	clk_enable(host->mck);
2293 	atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
2294 	host->bus_hz = clk_get_rate(host->mck);
2295 	clk_disable(host->mck);
2296 
2297 	host->mapbase = regs->start;
2298 
2299 	tasklet_init(&host->tasklet, atmci_tasklet_func, (unsigned long)host);
2300 
2301 	ret = request_irq(irq, atmci_interrupt, 0, dev_name(&pdev->dev), host);
2302 	if (ret)
2303 		goto err_request_irq;
2304 
2305 	/* Get MCI capabilities and set operations according to it */
2306 	atmci_get_cap(host);
2307 	if (host->caps.has_dma && atmci_configure_dma(host)) {
2308 		host->prepare_data = &atmci_prepare_data_dma;
2309 		host->submit_data = &atmci_submit_data_dma;
2310 		host->stop_transfer = &atmci_stop_transfer_dma;
2311 	} else if (host->caps.has_pdc) {
2312 		dev_info(&pdev->dev, "using PDC\n");
2313 		host->prepare_data = &atmci_prepare_data_pdc;
2314 		host->submit_data = &atmci_submit_data_pdc;
2315 		host->stop_transfer = &atmci_stop_transfer_pdc;
2316 	} else {
2317 		dev_info(&pdev->dev, "using PIO\n");
2318 		host->prepare_data = &atmci_prepare_data;
2319 		host->submit_data = &atmci_submit_data;
2320 		host->stop_transfer = &atmci_stop_transfer;
2321 	}
2322 
2323 	platform_set_drvdata(pdev, host);
2324 
2325 	setup_timer(&host->timer, atmci_timeout_timer, (unsigned long)host);
2326 
2327 	/* We need at least one slot to succeed */
2328 	nr_slots = 0;
2329 	ret = -ENODEV;
2330 	if (pdata->slot[0].bus_width) {
2331 		ret = atmci_init_slot(host, &pdata->slot[0],
2332 				0, ATMCI_SDCSEL_SLOT_A, ATMCI_SDIOIRQA);
2333 		if (!ret) {
2334 			nr_slots++;
2335 			host->buf_size = host->slot[0]->mmc->max_req_size;
2336 		}
2337 	}
2338 	if (pdata->slot[1].bus_width) {
2339 		ret = atmci_init_slot(host, &pdata->slot[1],
2340 				1, ATMCI_SDCSEL_SLOT_B, ATMCI_SDIOIRQB);
2341 		if (!ret) {
2342 			nr_slots++;
2343 			if (host->slot[1]->mmc->max_req_size > host->buf_size)
2344 				host->buf_size =
2345 					host->slot[1]->mmc->max_req_size;
2346 		}
2347 	}
2348 
2349 	if (!nr_slots) {
2350 		dev_err(&pdev->dev, "init failed: no slot defined\n");
2351 		goto err_init_slot;
2352 	}
2353 
2354 	if (!host->caps.has_rwproof) {
2355 		host->buffer = dma_alloc_coherent(&pdev->dev, host->buf_size,
2356 		                                  &host->buf_phys_addr,
2357 						  GFP_KERNEL);
2358 		if (!host->buffer) {
2359 			ret = -ENOMEM;
2360 			dev_err(&pdev->dev, "buffer allocation failed\n");
2361 			goto err_init_slot;
2362 		}
2363 	}
2364 
2365 	dev_info(&pdev->dev,
2366 			"Atmel MCI controller at 0x%08lx irq %d, %u slots\n",
2367 			host->mapbase, irq, nr_slots);
2368 
2369 	return 0;
2370 
2371 err_init_slot:
2372 	if (host->dma.chan)
2373 		dma_release_channel(host->dma.chan);
2374 	free_irq(irq, host);
2375 err_request_irq:
2376 	iounmap(host->regs);
2377 err_ioremap:
2378 	clk_put(host->mck);
2379 err_clk_get:
2380 	kfree(host);
2381 	return ret;
2382 }
2383 
2384 static int __exit atmci_remove(struct platform_device *pdev)
2385 {
2386 	struct atmel_mci	*host = platform_get_drvdata(pdev);
2387 	unsigned int		i;
2388 
2389 	platform_set_drvdata(pdev, NULL);
2390 
2391 	if (host->buffer)
2392 		dma_free_coherent(&pdev->dev, host->buf_size,
2393 		                  host->buffer, host->buf_phys_addr);
2394 
2395 	for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
2396 		if (host->slot[i])
2397 			atmci_cleanup_slot(host->slot[i], i);
2398 	}
2399 
2400 	clk_enable(host->mck);
2401 	atmci_writel(host, ATMCI_IDR, ~0UL);
2402 	atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIDIS);
2403 	atmci_readl(host, ATMCI_SR);
2404 	clk_disable(host->mck);
2405 
2406 #ifdef CONFIG_MMC_ATMELMCI_DMA
2407 	if (host->dma.chan)
2408 		dma_release_channel(host->dma.chan);
2409 #endif
2410 
2411 	free_irq(platform_get_irq(pdev, 0), host);
2412 	iounmap(host->regs);
2413 
2414 	clk_put(host->mck);
2415 	kfree(host);
2416 
2417 	return 0;
2418 }
2419 
2420 #ifdef CONFIG_PM
2421 static int atmci_suspend(struct device *dev)
2422 {
2423 	struct atmel_mci *host = dev_get_drvdata(dev);
2424 	int i;
2425 
2426 	 for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
2427 		struct atmel_mci_slot *slot = host->slot[i];
2428 		int ret;
2429 
2430 		if (!slot)
2431 			continue;
2432 		ret = mmc_suspend_host(slot->mmc);
2433 		if (ret < 0) {
2434 			while (--i >= 0) {
2435 				slot = host->slot[i];
2436 				if (slot
2437 				&& test_bit(ATMCI_SUSPENDED, &slot->flags)) {
2438 					mmc_resume_host(host->slot[i]->mmc);
2439 					clear_bit(ATMCI_SUSPENDED, &slot->flags);
2440 				}
2441 			}
2442 			return ret;
2443 		} else {
2444 			set_bit(ATMCI_SUSPENDED, &slot->flags);
2445 		}
2446 	}
2447 
2448 	return 0;
2449 }
2450 
2451 static int atmci_resume(struct device *dev)
2452 {
2453 	struct atmel_mci *host = dev_get_drvdata(dev);
2454 	int i;
2455 	int ret = 0;
2456 
2457 	for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
2458 		struct atmel_mci_slot *slot = host->slot[i];
2459 		int err;
2460 
2461 		slot = host->slot[i];
2462 		if (!slot)
2463 			continue;
2464 		if (!test_bit(ATMCI_SUSPENDED, &slot->flags))
2465 			continue;
2466 		err = mmc_resume_host(slot->mmc);
2467 		if (err < 0)
2468 			ret = err;
2469 		else
2470 			clear_bit(ATMCI_SUSPENDED, &slot->flags);
2471 	}
2472 
2473 	return ret;
2474 }
2475 static SIMPLE_DEV_PM_OPS(atmci_pm, atmci_suspend, atmci_resume);
2476 #define ATMCI_PM_OPS	(&atmci_pm)
2477 #else
2478 #define ATMCI_PM_OPS	NULL
2479 #endif
2480 
2481 static struct platform_driver atmci_driver = {
2482 	.remove		= __exit_p(atmci_remove),
2483 	.driver		= {
2484 		.name		= "atmel_mci",
2485 		.pm		= ATMCI_PM_OPS,
2486 	},
2487 };
2488 
2489 static int __init atmci_init(void)
2490 {
2491 	return platform_driver_probe(&atmci_driver, atmci_probe);
2492 }
2493 
2494 static void __exit atmci_exit(void)
2495 {
2496 	platform_driver_unregister(&atmci_driver);
2497 }
2498 
2499 late_initcall(atmci_init); /* try to load after dma driver when built-in */
2500 module_exit(atmci_exit);
2501 
2502 MODULE_DESCRIPTION("Atmel Multimedia Card Interface driver");
2503 MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
2504 MODULE_LICENSE("GPL v2");
2505