xref: /linux/drivers/mmc/host/atmel-mci.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
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 
28 #include <linux/mmc/host.h>
29 #include <linux/mmc/sdio.h>
30 
31 #include <mach/atmel-mci.h>
32 #include <linux/atmel-mci.h>
33 #include <linux/atmel_pdc.h>
34 
35 #include <asm/io.h>
36 #include <asm/unaligned.h>
37 
38 #include <mach/cpu.h>
39 #include <mach/board.h>
40 
41 #include "atmel-mci-regs.h"
42 
43 #define ATMCI_DATA_ERROR_FLAGS	(ATMCI_DCRCE | ATMCI_DTOE | ATMCI_OVRE | ATMCI_UNRE)
44 #define ATMCI_DMA_THRESHOLD	16
45 
46 enum {
47 	EVENT_CMD_COMPLETE = 0,
48 	EVENT_XFER_COMPLETE,
49 	EVENT_DATA_COMPLETE,
50 	EVENT_DATA_ERROR,
51 };
52 
53 enum atmel_mci_state {
54 	STATE_IDLE = 0,
55 	STATE_SENDING_CMD,
56 	STATE_SENDING_DATA,
57 	STATE_DATA_BUSY,
58 	STATE_SENDING_STOP,
59 	STATE_DATA_ERROR,
60 };
61 
62 enum atmci_xfer_dir {
63 	XFER_RECEIVE = 0,
64 	XFER_TRANSMIT,
65 };
66 
67 enum atmci_pdc_buf {
68 	PDC_FIRST_BUF = 0,
69 	PDC_SECOND_BUF,
70 };
71 
72 struct atmel_mci_caps {
73 	bool    has_dma;
74 	bool    has_pdc;
75 	bool    has_cfg_reg;
76 	bool    has_cstor_reg;
77 	bool    has_highspeed;
78 	bool    has_rwproof;
79 };
80 
81 struct atmel_mci_dma {
82 	struct dma_chan			*chan;
83 	struct dma_async_tx_descriptor	*data_desc;
84 };
85 
86 /**
87  * struct atmel_mci - MMC controller state shared between all slots
88  * @lock: Spinlock protecting the queue and associated data.
89  * @regs: Pointer to MMIO registers.
90  * @sg: Scatterlist entry currently being processed by PIO or PDC code.
91  * @pio_offset: Offset into the current scatterlist entry.
92  * @cur_slot: The slot which is currently using the controller.
93  * @mrq: The request currently being processed on @cur_slot,
94  *	or NULL if the controller is idle.
95  * @cmd: The command currently being sent to the card, or NULL.
96  * @data: The data currently being transferred, or NULL if no data
97  *	transfer is in progress.
98  * @data_size: just data->blocks * data->blksz.
99  * @dma: DMA client state.
100  * @data_chan: DMA channel being used for the current data transfer.
101  * @cmd_status: Snapshot of SR taken upon completion of the current
102  *	command. Only valid when EVENT_CMD_COMPLETE is pending.
103  * @data_status: Snapshot of SR taken upon completion of the current
104  *	data transfer. Only valid when EVENT_DATA_COMPLETE or
105  *	EVENT_DATA_ERROR is pending.
106  * @stop_cmdr: Value to be loaded into CMDR when the stop command is
107  *	to be sent.
108  * @tasklet: Tasklet running the request state machine.
109  * @pending_events: Bitmask of events flagged by the interrupt handler
110  *	to be processed by the tasklet.
111  * @completed_events: Bitmask of events which the state machine has
112  *	processed.
113  * @state: Tasklet state.
114  * @queue: List of slots waiting for access to the controller.
115  * @need_clock_update: Update the clock rate before the next request.
116  * @need_reset: Reset controller before next request.
117  * @mode_reg: Value of the MR register.
118  * @cfg_reg: Value of the CFG register.
119  * @bus_hz: The rate of @mck in Hz. This forms the basis for MMC bus
120  *	rate and timeout calculations.
121  * @mapbase: Physical address of the MMIO registers.
122  * @mck: The peripheral bus clock hooked up to the MMC controller.
123  * @pdev: Platform device associated with the MMC controller.
124  * @slot: Slots sharing this MMC controller.
125  * @caps: MCI capabilities depending on MCI version.
126  * @prepare_data: function to setup MCI before data transfer which
127  * depends on MCI capabilities.
128  * @submit_data: function to start data transfer which depends on MCI
129  * capabilities.
130  * @stop_transfer: function to stop data transfer which depends on MCI
131  * capabilities.
132  *
133  * Locking
134  * =======
135  *
136  * @lock is a softirq-safe spinlock protecting @queue as well as
137  * @cur_slot, @mrq and @state. These must always be updated
138  * at the same time while holding @lock.
139  *
140  * @lock also protects mode_reg and need_clock_update since these are
141  * used to synchronize mode register updates with the queue
142  * processing.
143  *
144  * The @mrq field of struct atmel_mci_slot is also protected by @lock,
145  * and must always be written at the same time as the slot is added to
146  * @queue.
147  *
148  * @pending_events and @completed_events are accessed using atomic bit
149  * operations, so they don't need any locking.
150  *
151  * None of the fields touched by the interrupt handler need any
152  * locking. However, ordering is important: Before EVENT_DATA_ERROR or
153  * EVENT_DATA_COMPLETE is set in @pending_events, all data-related
154  * interrupts must be disabled and @data_status updated with a
155  * snapshot of SR. Similarly, before EVENT_CMD_COMPLETE is set, the
156  * CMDRDY interrupt must be disabled and @cmd_status updated with a
157  * snapshot of SR, and before EVENT_XFER_COMPLETE can be set, the
158  * bytes_xfered field of @data must be written. This is ensured by
159  * using barriers.
160  */
161 struct atmel_mci {
162 	spinlock_t		lock;
163 	void __iomem		*regs;
164 
165 	struct scatterlist	*sg;
166 	unsigned int		pio_offset;
167 
168 	struct atmel_mci_slot	*cur_slot;
169 	struct mmc_request	*mrq;
170 	struct mmc_command	*cmd;
171 	struct mmc_data		*data;
172 	unsigned int		data_size;
173 
174 	struct atmel_mci_dma	dma;
175 	struct dma_chan		*data_chan;
176 
177 	u32			cmd_status;
178 	u32			data_status;
179 	u32			stop_cmdr;
180 
181 	struct tasklet_struct	tasklet;
182 	unsigned long		pending_events;
183 	unsigned long		completed_events;
184 	enum atmel_mci_state	state;
185 	struct list_head	queue;
186 
187 	bool			need_clock_update;
188 	bool			need_reset;
189 	u32			mode_reg;
190 	u32			cfg_reg;
191 	unsigned long		bus_hz;
192 	unsigned long		mapbase;
193 	struct clk		*mck;
194 	struct platform_device	*pdev;
195 
196 	struct atmel_mci_slot	*slot[ATMCI_MAX_NR_SLOTS];
197 
198 	struct atmel_mci_caps   caps;
199 
200 	u32 (*prepare_data)(struct atmel_mci *host, struct mmc_data *data);
201 	void (*submit_data)(struct atmel_mci *host, struct mmc_data *data);
202 	void (*stop_transfer)(struct atmel_mci *host);
203 };
204 
205 /**
206  * struct atmel_mci_slot - MMC slot state
207  * @mmc: The mmc_host representing this slot.
208  * @host: The MMC controller this slot is using.
209  * @sdc_reg: Value of SDCR to be written before using this slot.
210  * @sdio_irq: SDIO irq mask for this slot.
211  * @mrq: mmc_request currently being processed or waiting to be
212  *	processed, or NULL when the slot is idle.
213  * @queue_node: List node for placing this node in the @queue list of
214  *	&struct atmel_mci.
215  * @clock: Clock rate configured by set_ios(). Protected by host->lock.
216  * @flags: Random state bits associated with the slot.
217  * @detect_pin: GPIO pin used for card detection, or negative if not
218  *	available.
219  * @wp_pin: GPIO pin used for card write protect sending, or negative
220  *	if not available.
221  * @detect_is_active_high: The state of the detect pin when it is active.
222  * @detect_timer: Timer used for debouncing @detect_pin interrupts.
223  */
224 struct atmel_mci_slot {
225 	struct mmc_host		*mmc;
226 	struct atmel_mci	*host;
227 
228 	u32			sdc_reg;
229 	u32			sdio_irq;
230 
231 	struct mmc_request	*mrq;
232 	struct list_head	queue_node;
233 
234 	unsigned int		clock;
235 	unsigned long		flags;
236 #define ATMCI_CARD_PRESENT	0
237 #define ATMCI_CARD_NEED_INIT	1
238 #define ATMCI_SHUTDOWN		2
239 #define ATMCI_SUSPENDED		3
240 
241 	int			detect_pin;
242 	int			wp_pin;
243 	bool			detect_is_active_high;
244 
245 	struct timer_list	detect_timer;
246 };
247 
248 #define atmci_test_and_clear_pending(host, event)		\
249 	test_and_clear_bit(event, &host->pending_events)
250 #define atmci_set_completed(host, event)			\
251 	set_bit(event, &host->completed_events)
252 #define atmci_set_pending(host, event)				\
253 	set_bit(event, &host->pending_events)
254 
255 /*
256  * The debugfs stuff below is mostly optimized away when
257  * CONFIG_DEBUG_FS is not set.
258  */
259 static int atmci_req_show(struct seq_file *s, void *v)
260 {
261 	struct atmel_mci_slot	*slot = s->private;
262 	struct mmc_request	*mrq;
263 	struct mmc_command	*cmd;
264 	struct mmc_command	*stop;
265 	struct mmc_data		*data;
266 
267 	/* Make sure we get a consistent snapshot */
268 	spin_lock_bh(&slot->host->lock);
269 	mrq = slot->mrq;
270 
271 	if (mrq) {
272 		cmd = mrq->cmd;
273 		data = mrq->data;
274 		stop = mrq->stop;
275 
276 		if (cmd)
277 			seq_printf(s,
278 				"CMD%u(0x%x) flg %x rsp %x %x %x %x err %d\n",
279 				cmd->opcode, cmd->arg, cmd->flags,
280 				cmd->resp[0], cmd->resp[1], cmd->resp[2],
281 				cmd->resp[3], cmd->error);
282 		if (data)
283 			seq_printf(s, "DATA %u / %u * %u flg %x err %d\n",
284 				data->bytes_xfered, data->blocks,
285 				data->blksz, data->flags, data->error);
286 		if (stop)
287 			seq_printf(s,
288 				"CMD%u(0x%x) flg %x rsp %x %x %x %x err %d\n",
289 				stop->opcode, stop->arg, stop->flags,
290 				stop->resp[0], stop->resp[1], stop->resp[2],
291 				stop->resp[3], stop->error);
292 	}
293 
294 	spin_unlock_bh(&slot->host->lock);
295 
296 	return 0;
297 }
298 
299 static int atmci_req_open(struct inode *inode, struct file *file)
300 {
301 	return single_open(file, atmci_req_show, inode->i_private);
302 }
303 
304 static const struct file_operations atmci_req_fops = {
305 	.owner		= THIS_MODULE,
306 	.open		= atmci_req_open,
307 	.read		= seq_read,
308 	.llseek		= seq_lseek,
309 	.release	= single_release,
310 };
311 
312 static void atmci_show_status_reg(struct seq_file *s,
313 		const char *regname, u32 value)
314 {
315 	static const char	*sr_bit[] = {
316 		[0]	= "CMDRDY",
317 		[1]	= "RXRDY",
318 		[2]	= "TXRDY",
319 		[3]	= "BLKE",
320 		[4]	= "DTIP",
321 		[5]	= "NOTBUSY",
322 		[6]	= "ENDRX",
323 		[7]	= "ENDTX",
324 		[8]	= "SDIOIRQA",
325 		[9]	= "SDIOIRQB",
326 		[12]	= "SDIOWAIT",
327 		[14]	= "RXBUFF",
328 		[15]	= "TXBUFE",
329 		[16]	= "RINDE",
330 		[17]	= "RDIRE",
331 		[18]	= "RCRCE",
332 		[19]	= "RENDE",
333 		[20]	= "RTOE",
334 		[21]	= "DCRCE",
335 		[22]	= "DTOE",
336 		[23]	= "CSTOE",
337 		[24]	= "BLKOVRE",
338 		[25]	= "DMADONE",
339 		[26]	= "FIFOEMPTY",
340 		[27]	= "XFRDONE",
341 		[30]	= "OVRE",
342 		[31]	= "UNRE",
343 	};
344 	unsigned int		i;
345 
346 	seq_printf(s, "%s:\t0x%08x", regname, value);
347 	for (i = 0; i < ARRAY_SIZE(sr_bit); i++) {
348 		if (value & (1 << i)) {
349 			if (sr_bit[i])
350 				seq_printf(s, " %s", sr_bit[i]);
351 			else
352 				seq_puts(s, " UNKNOWN");
353 		}
354 	}
355 	seq_putc(s, '\n');
356 }
357 
358 static int atmci_regs_show(struct seq_file *s, void *v)
359 {
360 	struct atmel_mci	*host = s->private;
361 	u32			*buf;
362 
363 	buf = kmalloc(ATMCI_REGS_SIZE, GFP_KERNEL);
364 	if (!buf)
365 		return -ENOMEM;
366 
367 	/*
368 	 * Grab a more or less consistent snapshot. Note that we're
369 	 * not disabling interrupts, so IMR and SR may not be
370 	 * consistent.
371 	 */
372 	spin_lock_bh(&host->lock);
373 	clk_enable(host->mck);
374 	memcpy_fromio(buf, host->regs, ATMCI_REGS_SIZE);
375 	clk_disable(host->mck);
376 	spin_unlock_bh(&host->lock);
377 
378 	seq_printf(s, "MR:\t0x%08x%s%s CLKDIV=%u\n",
379 			buf[ATMCI_MR / 4],
380 			buf[ATMCI_MR / 4] & ATMCI_MR_RDPROOF ? " RDPROOF" : "",
381 			buf[ATMCI_MR / 4] & ATMCI_MR_WRPROOF ? " WRPROOF" : "",
382 			buf[ATMCI_MR / 4] & 0xff);
383 	seq_printf(s, "DTOR:\t0x%08x\n", buf[ATMCI_DTOR / 4]);
384 	seq_printf(s, "SDCR:\t0x%08x\n", buf[ATMCI_SDCR / 4]);
385 	seq_printf(s, "ARGR:\t0x%08x\n", buf[ATMCI_ARGR / 4]);
386 	seq_printf(s, "BLKR:\t0x%08x BCNT=%u BLKLEN=%u\n",
387 			buf[ATMCI_BLKR / 4],
388 			buf[ATMCI_BLKR / 4] & 0xffff,
389 			(buf[ATMCI_BLKR / 4] >> 16) & 0xffff);
390 	if (host->caps.has_cstor_reg)
391 		seq_printf(s, "CSTOR:\t0x%08x\n", buf[ATMCI_CSTOR / 4]);
392 
393 	/* Don't read RSPR and RDR; it will consume the data there */
394 
395 	atmci_show_status_reg(s, "SR", buf[ATMCI_SR / 4]);
396 	atmci_show_status_reg(s, "IMR", buf[ATMCI_IMR / 4]);
397 
398 	if (host->caps.has_dma) {
399 		u32 val;
400 
401 		val = buf[ATMCI_DMA / 4];
402 		seq_printf(s, "DMA:\t0x%08x OFFSET=%u CHKSIZE=%u%s\n",
403 				val, val & 3,
404 				((val >> 4) & 3) ?
405 					1 << (((val >> 4) & 3) + 1) : 1,
406 				val & ATMCI_DMAEN ? " DMAEN" : "");
407 	}
408 	if (host->caps.has_cfg_reg) {
409 		u32 val;
410 
411 		val = buf[ATMCI_CFG / 4];
412 		seq_printf(s, "CFG:\t0x%08x%s%s%s%s\n",
413 				val,
414 				val & ATMCI_CFG_FIFOMODE_1DATA ? " FIFOMODE_ONE_DATA" : "",
415 				val & ATMCI_CFG_FERRCTRL_COR ? " FERRCTRL_CLEAR_ON_READ" : "",
416 				val & ATMCI_CFG_HSMODE ? " HSMODE" : "",
417 				val & ATMCI_CFG_LSYNC ? " LSYNC" : "");
418 	}
419 
420 	kfree(buf);
421 
422 	return 0;
423 }
424 
425 static int atmci_regs_open(struct inode *inode, struct file *file)
426 {
427 	return single_open(file, atmci_regs_show, inode->i_private);
428 }
429 
430 static const struct file_operations atmci_regs_fops = {
431 	.owner		= THIS_MODULE,
432 	.open		= atmci_regs_open,
433 	.read		= seq_read,
434 	.llseek		= seq_lseek,
435 	.release	= single_release,
436 };
437 
438 static void atmci_init_debugfs(struct atmel_mci_slot *slot)
439 {
440 	struct mmc_host		*mmc = slot->mmc;
441 	struct atmel_mci	*host = slot->host;
442 	struct dentry		*root;
443 	struct dentry		*node;
444 
445 	root = mmc->debugfs_root;
446 	if (!root)
447 		return;
448 
449 	node = debugfs_create_file("regs", S_IRUSR, root, host,
450 			&atmci_regs_fops);
451 	if (IS_ERR(node))
452 		return;
453 	if (!node)
454 		goto err;
455 
456 	node = debugfs_create_file("req", S_IRUSR, root, slot, &atmci_req_fops);
457 	if (!node)
458 		goto err;
459 
460 	node = debugfs_create_u32("state", S_IRUSR, root, (u32 *)&host->state);
461 	if (!node)
462 		goto err;
463 
464 	node = debugfs_create_x32("pending_events", S_IRUSR, root,
465 				     (u32 *)&host->pending_events);
466 	if (!node)
467 		goto err;
468 
469 	node = debugfs_create_x32("completed_events", S_IRUSR, root,
470 				     (u32 *)&host->completed_events);
471 	if (!node)
472 		goto err;
473 
474 	return;
475 
476 err:
477 	dev_err(&mmc->class_dev, "failed to initialize debugfs for slot\n");
478 }
479 
480 static inline unsigned int atmci_ns_to_clocks(struct atmel_mci *host,
481 					unsigned int ns)
482 {
483 	return (ns * (host->bus_hz / 1000000) + 999) / 1000;
484 }
485 
486 static void atmci_set_timeout(struct atmel_mci *host,
487 		struct atmel_mci_slot *slot, struct mmc_data *data)
488 {
489 	static unsigned	dtomul_to_shift[] = {
490 		0, 4, 7, 8, 10, 12, 16, 20
491 	};
492 	unsigned	timeout;
493 	unsigned	dtocyc;
494 	unsigned	dtomul;
495 
496 	timeout = atmci_ns_to_clocks(host, data->timeout_ns)
497 		+ data->timeout_clks;
498 
499 	for (dtomul = 0; dtomul < 8; dtomul++) {
500 		unsigned shift = dtomul_to_shift[dtomul];
501 		dtocyc = (timeout + (1 << shift) - 1) >> shift;
502 		if (dtocyc < 15)
503 			break;
504 	}
505 
506 	if (dtomul >= 8) {
507 		dtomul = 7;
508 		dtocyc = 15;
509 	}
510 
511 	dev_vdbg(&slot->mmc->class_dev, "setting timeout to %u cycles\n",
512 			dtocyc << dtomul_to_shift[dtomul]);
513 	atmci_writel(host, ATMCI_DTOR, (ATMCI_DTOMUL(dtomul) | ATMCI_DTOCYC(dtocyc)));
514 }
515 
516 /*
517  * Return mask with command flags to be enabled for this command.
518  */
519 static u32 atmci_prepare_command(struct mmc_host *mmc,
520 				 struct mmc_command *cmd)
521 {
522 	struct mmc_data	*data;
523 	u32		cmdr;
524 
525 	cmd->error = -EINPROGRESS;
526 
527 	cmdr = ATMCI_CMDR_CMDNB(cmd->opcode);
528 
529 	if (cmd->flags & MMC_RSP_PRESENT) {
530 		if (cmd->flags & MMC_RSP_136)
531 			cmdr |= ATMCI_CMDR_RSPTYP_136BIT;
532 		else
533 			cmdr |= ATMCI_CMDR_RSPTYP_48BIT;
534 	}
535 
536 	/*
537 	 * This should really be MAXLAT_5 for CMD2 and ACMD41, but
538 	 * it's too difficult to determine whether this is an ACMD or
539 	 * not. Better make it 64.
540 	 */
541 	cmdr |= ATMCI_CMDR_MAXLAT_64CYC;
542 
543 	if (mmc->ios.bus_mode == MMC_BUSMODE_OPENDRAIN)
544 		cmdr |= ATMCI_CMDR_OPDCMD;
545 
546 	data = cmd->data;
547 	if (data) {
548 		cmdr |= ATMCI_CMDR_START_XFER;
549 
550 		if (cmd->opcode == SD_IO_RW_EXTENDED) {
551 			cmdr |= ATMCI_CMDR_SDIO_BLOCK;
552 		} else {
553 			if (data->flags & MMC_DATA_STREAM)
554 				cmdr |= ATMCI_CMDR_STREAM;
555 			else if (data->blocks > 1)
556 				cmdr |= ATMCI_CMDR_MULTI_BLOCK;
557 			else
558 				cmdr |= ATMCI_CMDR_BLOCK;
559 		}
560 
561 		if (data->flags & MMC_DATA_READ)
562 			cmdr |= ATMCI_CMDR_TRDIR_READ;
563 	}
564 
565 	return cmdr;
566 }
567 
568 static void atmci_send_command(struct atmel_mci *host,
569 		struct mmc_command *cmd, u32 cmd_flags)
570 {
571 	WARN_ON(host->cmd);
572 	host->cmd = cmd;
573 
574 	dev_vdbg(&host->pdev->dev,
575 			"start command: ARGR=0x%08x CMDR=0x%08x\n",
576 			cmd->arg, cmd_flags);
577 
578 	atmci_writel(host, ATMCI_ARGR, cmd->arg);
579 	atmci_writel(host, ATMCI_CMDR, cmd_flags);
580 }
581 
582 static void atmci_send_stop_cmd(struct atmel_mci *host, struct mmc_data *data)
583 {
584 	atmci_send_command(host, data->stop, host->stop_cmdr);
585 	atmci_writel(host, ATMCI_IER, ATMCI_CMDRDY);
586 }
587 
588 /*
589  * Configure given PDC buffer taking care of alignement issues.
590  * Update host->data_size and host->sg.
591  */
592 static void atmci_pdc_set_single_buf(struct atmel_mci *host,
593 	enum atmci_xfer_dir dir, enum atmci_pdc_buf buf_nb)
594 {
595 	u32 pointer_reg, counter_reg;
596 
597 	if (dir == XFER_RECEIVE) {
598 		pointer_reg = ATMEL_PDC_RPR;
599 		counter_reg = ATMEL_PDC_RCR;
600 	} else {
601 		pointer_reg = ATMEL_PDC_TPR;
602 		counter_reg = ATMEL_PDC_TCR;
603 	}
604 
605 	if (buf_nb == PDC_SECOND_BUF) {
606 		pointer_reg += ATMEL_PDC_SCND_BUF_OFF;
607 		counter_reg += ATMEL_PDC_SCND_BUF_OFF;
608 	}
609 
610 	atmci_writel(host, pointer_reg, sg_dma_address(host->sg));
611 	if (host->data_size <= sg_dma_len(host->sg)) {
612 		if (host->data_size & 0x3) {
613 			/* If size is different from modulo 4, transfer bytes */
614 			atmci_writel(host, counter_reg, host->data_size);
615 			atmci_writel(host, ATMCI_MR, host->mode_reg | ATMCI_MR_PDCFBYTE);
616 		} else {
617 			/* Else transfer 32-bits words */
618 			atmci_writel(host, counter_reg, host->data_size / 4);
619 		}
620 		host->data_size = 0;
621 	} else {
622 		/* We assume the size of a page is 32-bits aligned */
623 		atmci_writel(host, counter_reg, sg_dma_len(host->sg) / 4);
624 		host->data_size -= sg_dma_len(host->sg);
625 		if (host->data_size)
626 			host->sg = sg_next(host->sg);
627 	}
628 }
629 
630 /*
631  * Configure PDC buffer according to the data size ie configuring one or two
632  * buffers. Don't use this function if you want to configure only the second
633  * buffer. In this case, use atmci_pdc_set_single_buf.
634  */
635 static void atmci_pdc_set_both_buf(struct atmel_mci *host, int dir)
636 {
637 	atmci_pdc_set_single_buf(host, dir, PDC_FIRST_BUF);
638 	if (host->data_size)
639 		atmci_pdc_set_single_buf(host, dir, PDC_SECOND_BUF);
640 }
641 
642 /*
643  * Unmap sg lists, called when transfer is finished.
644  */
645 static void atmci_pdc_cleanup(struct atmel_mci *host)
646 {
647 	struct mmc_data         *data = host->data;
648 
649 	if (data)
650 		dma_unmap_sg(&host->pdev->dev,
651 				data->sg, data->sg_len,
652 				((data->flags & MMC_DATA_WRITE)
653 				 ? DMA_TO_DEVICE : DMA_FROM_DEVICE));
654 }
655 
656 /*
657  * Disable PDC transfers. Update pending flags to EVENT_XFER_COMPLETE after
658  * having received ATMCI_TXBUFE or ATMCI_RXBUFF interrupt. Enable ATMCI_NOTBUSY
659  * interrupt needed for both transfer directions.
660  */
661 static void atmci_pdc_complete(struct atmel_mci *host)
662 {
663 	atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
664 	atmci_pdc_cleanup(host);
665 
666 	/*
667 	 * If the card was removed, data will be NULL. No point trying
668 	 * to send the stop command or waiting for NBUSY in this case.
669 	 */
670 	if (host->data) {
671 		atmci_set_pending(host, EVENT_XFER_COMPLETE);
672 		tasklet_schedule(&host->tasklet);
673 		atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
674 	}
675 }
676 
677 static void atmci_dma_cleanup(struct atmel_mci *host)
678 {
679 	struct mmc_data                 *data = host->data;
680 
681 	if (data)
682 		dma_unmap_sg(host->dma.chan->device->dev,
683 				data->sg, data->sg_len,
684 				((data->flags & MMC_DATA_WRITE)
685 				 ? DMA_TO_DEVICE : DMA_FROM_DEVICE));
686 }
687 
688 /*
689  * This function is called by the DMA driver from tasklet context.
690  */
691 static void atmci_dma_complete(void *arg)
692 {
693 	struct atmel_mci	*host = arg;
694 	struct mmc_data		*data = host->data;
695 
696 	dev_vdbg(&host->pdev->dev, "DMA complete\n");
697 
698 	if (host->caps.has_dma)
699 		/* Disable DMA hardware handshaking on MCI */
700 		atmci_writel(host, ATMCI_DMA, atmci_readl(host, ATMCI_DMA) & ~ATMCI_DMAEN);
701 
702 	atmci_dma_cleanup(host);
703 
704 	/*
705 	 * If the card was removed, data will be NULL. No point trying
706 	 * to send the stop command or waiting for NBUSY in this case.
707 	 */
708 	if (data) {
709 		atmci_set_pending(host, EVENT_XFER_COMPLETE);
710 		tasklet_schedule(&host->tasklet);
711 
712 		/*
713 		 * Regardless of what the documentation says, we have
714 		 * to wait for NOTBUSY even after block read
715 		 * operations.
716 		 *
717 		 * When the DMA transfer is complete, the controller
718 		 * may still be reading the CRC from the card, i.e.
719 		 * the data transfer is still in progress and we
720 		 * haven't seen all the potential error bits yet.
721 		 *
722 		 * The interrupt handler will schedule a different
723 		 * tasklet to finish things up when the data transfer
724 		 * is completely done.
725 		 *
726 		 * We may not complete the mmc request here anyway
727 		 * because the mmc layer may call back and cause us to
728 		 * violate the "don't submit new operations from the
729 		 * completion callback" rule of the dma engine
730 		 * framework.
731 		 */
732 		atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
733 	}
734 }
735 
736 /*
737  * Returns a mask of interrupt flags to be enabled after the whole
738  * request has been prepared.
739  */
740 static u32 atmci_prepare_data(struct atmel_mci *host, struct mmc_data *data)
741 {
742 	u32 iflags;
743 
744 	data->error = -EINPROGRESS;
745 
746 	host->sg = data->sg;
747 	host->data = data;
748 	host->data_chan = NULL;
749 
750 	iflags = ATMCI_DATA_ERROR_FLAGS;
751 
752 	/*
753 	 * Errata: MMC data write operation with less than 12
754 	 * bytes is impossible.
755 	 *
756 	 * Errata: MCI Transmit Data Register (TDR) FIFO
757 	 * corruption when length is not multiple of 4.
758 	 */
759 	if (data->blocks * data->blksz < 12
760 			|| (data->blocks * data->blksz) & 3)
761 		host->need_reset = true;
762 
763 	host->pio_offset = 0;
764 	if (data->flags & MMC_DATA_READ)
765 		iflags |= ATMCI_RXRDY;
766 	else
767 		iflags |= ATMCI_TXRDY;
768 
769 	return iflags;
770 }
771 
772 /*
773  * Set interrupt flags and set block length into the MCI mode register even
774  * if this value is also accessible in the MCI block register. It seems to be
775  * necessary before the High Speed MCI version. It also map sg and configure
776  * PDC registers.
777  */
778 static u32
779 atmci_prepare_data_pdc(struct atmel_mci *host, struct mmc_data *data)
780 {
781 	u32 iflags, tmp;
782 	unsigned int sg_len;
783 	enum dma_data_direction dir;
784 
785 	data->error = -EINPROGRESS;
786 
787 	host->data = data;
788 	host->sg = data->sg;
789 	iflags = ATMCI_DATA_ERROR_FLAGS;
790 
791 	/* Enable pdc mode */
792 	atmci_writel(host, ATMCI_MR, host->mode_reg | ATMCI_MR_PDCMODE);
793 
794 	if (data->flags & MMC_DATA_READ) {
795 		dir = DMA_FROM_DEVICE;
796 		iflags |= ATMCI_ENDRX | ATMCI_RXBUFF;
797 	} else {
798 		dir = DMA_TO_DEVICE;
799 		iflags |= ATMCI_ENDTX | ATMCI_TXBUFE;
800 	}
801 
802 	/* Set BLKLEN */
803 	tmp = atmci_readl(host, ATMCI_MR);
804 	tmp &= 0x0000ffff;
805 	tmp |= ATMCI_BLKLEN(data->blksz);
806 	atmci_writel(host, ATMCI_MR, tmp);
807 
808 	/* Configure PDC */
809 	host->data_size = data->blocks * data->blksz;
810 	sg_len = dma_map_sg(&host->pdev->dev, data->sg, data->sg_len, dir);
811 	if (host->data_size)
812 		atmci_pdc_set_both_buf(host,
813 			((dir == DMA_FROM_DEVICE) ? XFER_RECEIVE : XFER_TRANSMIT));
814 
815 	return iflags;
816 }
817 
818 static u32
819 atmci_prepare_data_dma(struct atmel_mci *host, struct mmc_data *data)
820 {
821 	struct dma_chan			*chan;
822 	struct dma_async_tx_descriptor	*desc;
823 	struct scatterlist		*sg;
824 	unsigned int			i;
825 	enum dma_data_direction		direction;
826 	unsigned int			sglen;
827 	u32 iflags;
828 
829 	data->error = -EINPROGRESS;
830 
831 	WARN_ON(host->data);
832 	host->sg = NULL;
833 	host->data = data;
834 
835 	iflags = ATMCI_DATA_ERROR_FLAGS;
836 
837 	/*
838 	 * We don't do DMA on "complex" transfers, i.e. with
839 	 * non-word-aligned buffers or lengths. Also, we don't bother
840 	 * with all the DMA setup overhead for short transfers.
841 	 */
842 	if (data->blocks * data->blksz < ATMCI_DMA_THRESHOLD)
843 		return atmci_prepare_data(host, data);
844 	if (data->blksz & 3)
845 		return atmci_prepare_data(host, data);
846 
847 	for_each_sg(data->sg, sg, data->sg_len, i) {
848 		if (sg->offset & 3 || sg->length & 3)
849 			return atmci_prepare_data(host, data);
850 	}
851 
852 	/* If we don't have a channel, we can't do DMA */
853 	chan = host->dma.chan;
854 	if (chan)
855 		host->data_chan = chan;
856 
857 	if (!chan)
858 		return -ENODEV;
859 
860 	if (host->caps.has_dma)
861 		atmci_writel(host, ATMCI_DMA, ATMCI_DMA_CHKSIZE(3) | ATMCI_DMAEN);
862 
863 	if (data->flags & MMC_DATA_READ)
864 		direction = DMA_FROM_DEVICE;
865 	else
866 		direction = DMA_TO_DEVICE;
867 
868 	sglen = dma_map_sg(chan->device->dev, data->sg,
869 			data->sg_len, direction);
870 
871 	desc = chan->device->device_prep_slave_sg(chan,
872 			data->sg, sglen, direction,
873 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
874 	if (!desc)
875 		goto unmap_exit;
876 
877 	host->dma.data_desc = desc;
878 	desc->callback = atmci_dma_complete;
879 	desc->callback_param = host;
880 
881 	return iflags;
882 unmap_exit:
883 	dma_unmap_sg(chan->device->dev, data->sg, data->sg_len, direction);
884 	return -ENOMEM;
885 }
886 
887 static void
888 atmci_submit_data(struct atmel_mci *host, struct mmc_data *data)
889 {
890 	return;
891 }
892 
893 /*
894  * Start PDC according to transfer direction.
895  */
896 static void
897 atmci_submit_data_pdc(struct atmel_mci *host, struct mmc_data *data)
898 {
899 	if (data->flags & MMC_DATA_READ)
900 		atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTEN);
901 	else
902 		atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN);
903 }
904 
905 static void
906 atmci_submit_data_dma(struct atmel_mci *host, struct mmc_data *data)
907 {
908 	struct dma_chan			*chan = host->data_chan;
909 	struct dma_async_tx_descriptor	*desc = host->dma.data_desc;
910 
911 	if (chan) {
912 		dmaengine_submit(desc);
913 		dma_async_issue_pending(chan);
914 	}
915 }
916 
917 static void atmci_stop_transfer(struct atmel_mci *host)
918 {
919 	atmci_set_pending(host, EVENT_XFER_COMPLETE);
920 	atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
921 }
922 
923 /*
924  * Stop data transfer because error(s) occured.
925  */
926 static void atmci_stop_transfer_pdc(struct atmel_mci *host)
927 {
928 	atmci_set_pending(host, EVENT_XFER_COMPLETE);
929 	atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
930 }
931 
932 static void atmci_stop_transfer_dma(struct atmel_mci *host)
933 {
934 	struct dma_chan *chan = host->data_chan;
935 
936 	if (chan) {
937 		dmaengine_terminate_all(chan);
938 		atmci_dma_cleanup(host);
939 	} else {
940 		/* Data transfer was stopped by the interrupt handler */
941 		atmci_set_pending(host, EVENT_XFER_COMPLETE);
942 		atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
943 	}
944 }
945 
946 /*
947  * Start a request: prepare data if needed, prepare the command and activate
948  * interrupts.
949  */
950 static void atmci_start_request(struct atmel_mci *host,
951 		struct atmel_mci_slot *slot)
952 {
953 	struct mmc_request	*mrq;
954 	struct mmc_command	*cmd;
955 	struct mmc_data		*data;
956 	u32			iflags;
957 	u32			cmdflags;
958 
959 	mrq = slot->mrq;
960 	host->cur_slot = slot;
961 	host->mrq = mrq;
962 
963 	host->pending_events = 0;
964 	host->completed_events = 0;
965 	host->data_status = 0;
966 
967 	if (host->need_reset) {
968 		atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
969 		atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
970 		atmci_writel(host, ATMCI_MR, host->mode_reg);
971 		if (host->caps.has_cfg_reg)
972 			atmci_writel(host, ATMCI_CFG, host->cfg_reg);
973 		host->need_reset = false;
974 	}
975 	atmci_writel(host, ATMCI_SDCR, slot->sdc_reg);
976 
977 	iflags = atmci_readl(host, ATMCI_IMR);
978 	if (iflags & ~(ATMCI_SDIOIRQA | ATMCI_SDIOIRQB))
979 		dev_warn(&slot->mmc->class_dev, "WARNING: IMR=0x%08x\n",
980 				iflags);
981 
982 	if (unlikely(test_and_clear_bit(ATMCI_CARD_NEED_INIT, &slot->flags))) {
983 		/* Send init sequence (74 clock cycles) */
984 		atmci_writel(host, ATMCI_CMDR, ATMCI_CMDR_SPCMD_INIT);
985 		while (!(atmci_readl(host, ATMCI_SR) & ATMCI_CMDRDY))
986 			cpu_relax();
987 	}
988 	iflags = 0;
989 	data = mrq->data;
990 	if (data) {
991 		atmci_set_timeout(host, slot, data);
992 
993 		/* Must set block count/size before sending command */
994 		atmci_writel(host, ATMCI_BLKR, ATMCI_BCNT(data->blocks)
995 				| ATMCI_BLKLEN(data->blksz));
996 		dev_vdbg(&slot->mmc->class_dev, "BLKR=0x%08x\n",
997 			ATMCI_BCNT(data->blocks) | ATMCI_BLKLEN(data->blksz));
998 
999 		iflags |= host->prepare_data(host, data);
1000 	}
1001 
1002 	iflags |= ATMCI_CMDRDY;
1003 	cmd = mrq->cmd;
1004 	cmdflags = atmci_prepare_command(slot->mmc, cmd);
1005 	atmci_send_command(host, cmd, cmdflags);
1006 
1007 	if (data)
1008 		host->submit_data(host, data);
1009 
1010 	if (mrq->stop) {
1011 		host->stop_cmdr = atmci_prepare_command(slot->mmc, mrq->stop);
1012 		host->stop_cmdr |= ATMCI_CMDR_STOP_XFER;
1013 		if (!(data->flags & MMC_DATA_WRITE))
1014 			host->stop_cmdr |= ATMCI_CMDR_TRDIR_READ;
1015 		if (data->flags & MMC_DATA_STREAM)
1016 			host->stop_cmdr |= ATMCI_CMDR_STREAM;
1017 		else
1018 			host->stop_cmdr |= ATMCI_CMDR_MULTI_BLOCK;
1019 	}
1020 
1021 	/*
1022 	 * We could have enabled interrupts earlier, but I suspect
1023 	 * that would open up a nice can of interesting race
1024 	 * conditions (e.g. command and data complete, but stop not
1025 	 * prepared yet.)
1026 	 */
1027 	atmci_writel(host, ATMCI_IER, iflags);
1028 }
1029 
1030 static void atmci_queue_request(struct atmel_mci *host,
1031 		struct atmel_mci_slot *slot, struct mmc_request *mrq)
1032 {
1033 	dev_vdbg(&slot->mmc->class_dev, "queue request: state=%d\n",
1034 			host->state);
1035 
1036 	spin_lock_bh(&host->lock);
1037 	slot->mrq = mrq;
1038 	if (host->state == STATE_IDLE) {
1039 		host->state = STATE_SENDING_CMD;
1040 		atmci_start_request(host, slot);
1041 	} else {
1042 		list_add_tail(&slot->queue_node, &host->queue);
1043 	}
1044 	spin_unlock_bh(&host->lock);
1045 }
1046 
1047 static void atmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
1048 {
1049 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1050 	struct atmel_mci	*host = slot->host;
1051 	struct mmc_data		*data;
1052 
1053 	WARN_ON(slot->mrq);
1054 
1055 	/*
1056 	 * We may "know" the card is gone even though there's still an
1057 	 * electrical connection. If so, we really need to communicate
1058 	 * this to the MMC core since there won't be any more
1059 	 * interrupts as the card is completely removed. Otherwise,
1060 	 * the MMC core might believe the card is still there even
1061 	 * though the card was just removed very slowly.
1062 	 */
1063 	if (!test_bit(ATMCI_CARD_PRESENT, &slot->flags)) {
1064 		mrq->cmd->error = -ENOMEDIUM;
1065 		mmc_request_done(mmc, mrq);
1066 		return;
1067 	}
1068 
1069 	/* We don't support multiple blocks of weird lengths. */
1070 	data = mrq->data;
1071 	if (data && data->blocks > 1 && data->blksz & 3) {
1072 		mrq->cmd->error = -EINVAL;
1073 		mmc_request_done(mmc, mrq);
1074 	}
1075 
1076 	atmci_queue_request(host, slot, mrq);
1077 }
1078 
1079 static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
1080 {
1081 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1082 	struct atmel_mci	*host = slot->host;
1083 	unsigned int		i;
1084 
1085 	slot->sdc_reg &= ~ATMCI_SDCBUS_MASK;
1086 	switch (ios->bus_width) {
1087 	case MMC_BUS_WIDTH_1:
1088 		slot->sdc_reg |= ATMCI_SDCBUS_1BIT;
1089 		break;
1090 	case MMC_BUS_WIDTH_4:
1091 		slot->sdc_reg |= ATMCI_SDCBUS_4BIT;
1092 		break;
1093 	}
1094 
1095 	if (ios->clock) {
1096 		unsigned int clock_min = ~0U;
1097 		u32 clkdiv;
1098 
1099 		spin_lock_bh(&host->lock);
1100 		if (!host->mode_reg) {
1101 			clk_enable(host->mck);
1102 			atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
1103 			atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
1104 			if (host->caps.has_cfg_reg)
1105 				atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1106 		}
1107 
1108 		/*
1109 		 * Use mirror of ios->clock to prevent race with mmc
1110 		 * core ios update when finding the minimum.
1111 		 */
1112 		slot->clock = ios->clock;
1113 		for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
1114 			if (host->slot[i] && host->slot[i]->clock
1115 					&& host->slot[i]->clock < clock_min)
1116 				clock_min = host->slot[i]->clock;
1117 		}
1118 
1119 		/* Calculate clock divider */
1120 		clkdiv = DIV_ROUND_UP(host->bus_hz, 2 * clock_min) - 1;
1121 		if (clkdiv > 255) {
1122 			dev_warn(&mmc->class_dev,
1123 				"clock %u too slow; using %lu\n",
1124 				clock_min, host->bus_hz / (2 * 256));
1125 			clkdiv = 255;
1126 		}
1127 
1128 		host->mode_reg = ATMCI_MR_CLKDIV(clkdiv);
1129 
1130 		/*
1131 		 * WRPROOF and RDPROOF prevent overruns/underruns by
1132 		 * stopping the clock when the FIFO is full/empty.
1133 		 * This state is not expected to last for long.
1134 		 */
1135 		if (host->caps.has_rwproof)
1136 			host->mode_reg |= (ATMCI_MR_WRPROOF | ATMCI_MR_RDPROOF);
1137 
1138 		if (host->caps.has_cfg_reg) {
1139 			/* setup High Speed mode in relation with card capacity */
1140 			if (ios->timing == MMC_TIMING_SD_HS)
1141 				host->cfg_reg |= ATMCI_CFG_HSMODE;
1142 			else
1143 				host->cfg_reg &= ~ATMCI_CFG_HSMODE;
1144 		}
1145 
1146 		if (list_empty(&host->queue)) {
1147 			atmci_writel(host, ATMCI_MR, host->mode_reg);
1148 			if (host->caps.has_cfg_reg)
1149 				atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1150 		} else {
1151 			host->need_clock_update = true;
1152 		}
1153 
1154 		spin_unlock_bh(&host->lock);
1155 	} else {
1156 		bool any_slot_active = false;
1157 
1158 		spin_lock_bh(&host->lock);
1159 		slot->clock = 0;
1160 		for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
1161 			if (host->slot[i] && host->slot[i]->clock) {
1162 				any_slot_active = true;
1163 				break;
1164 			}
1165 		}
1166 		if (!any_slot_active) {
1167 			atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIDIS);
1168 			if (host->mode_reg) {
1169 				atmci_readl(host, ATMCI_MR);
1170 				clk_disable(host->mck);
1171 			}
1172 			host->mode_reg = 0;
1173 		}
1174 		spin_unlock_bh(&host->lock);
1175 	}
1176 
1177 	switch (ios->power_mode) {
1178 	case MMC_POWER_UP:
1179 		set_bit(ATMCI_CARD_NEED_INIT, &slot->flags);
1180 		break;
1181 	default:
1182 		/*
1183 		 * TODO: None of the currently available AVR32-based
1184 		 * boards allow MMC power to be turned off. Implement
1185 		 * power control when this can be tested properly.
1186 		 *
1187 		 * We also need to hook this into the clock management
1188 		 * somehow so that newly inserted cards aren't
1189 		 * subjected to a fast clock before we have a chance
1190 		 * to figure out what the maximum rate is. Currently,
1191 		 * there's no way to avoid this, and there never will
1192 		 * be for boards that don't support power control.
1193 		 */
1194 		break;
1195 	}
1196 }
1197 
1198 static int atmci_get_ro(struct mmc_host *mmc)
1199 {
1200 	int			read_only = -ENOSYS;
1201 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1202 
1203 	if (gpio_is_valid(slot->wp_pin)) {
1204 		read_only = gpio_get_value(slot->wp_pin);
1205 		dev_dbg(&mmc->class_dev, "card is %s\n",
1206 				read_only ? "read-only" : "read-write");
1207 	}
1208 
1209 	return read_only;
1210 }
1211 
1212 static int atmci_get_cd(struct mmc_host *mmc)
1213 {
1214 	int			present = -ENOSYS;
1215 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1216 
1217 	if (gpio_is_valid(slot->detect_pin)) {
1218 		present = !(gpio_get_value(slot->detect_pin) ^
1219 			    slot->detect_is_active_high);
1220 		dev_dbg(&mmc->class_dev, "card is %spresent\n",
1221 				present ? "" : "not ");
1222 	}
1223 
1224 	return present;
1225 }
1226 
1227 static void atmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
1228 {
1229 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
1230 	struct atmel_mci	*host = slot->host;
1231 
1232 	if (enable)
1233 		atmci_writel(host, ATMCI_IER, slot->sdio_irq);
1234 	else
1235 		atmci_writel(host, ATMCI_IDR, slot->sdio_irq);
1236 }
1237 
1238 static const struct mmc_host_ops atmci_ops = {
1239 	.request	= atmci_request,
1240 	.set_ios	= atmci_set_ios,
1241 	.get_ro		= atmci_get_ro,
1242 	.get_cd		= atmci_get_cd,
1243 	.enable_sdio_irq = atmci_enable_sdio_irq,
1244 };
1245 
1246 /* Called with host->lock held */
1247 static void atmci_request_end(struct atmel_mci *host, struct mmc_request *mrq)
1248 	__releases(&host->lock)
1249 	__acquires(&host->lock)
1250 {
1251 	struct atmel_mci_slot	*slot = NULL;
1252 	struct mmc_host		*prev_mmc = host->cur_slot->mmc;
1253 
1254 	WARN_ON(host->cmd || host->data);
1255 
1256 	/*
1257 	 * Update the MMC clock rate if necessary. This may be
1258 	 * necessary if set_ios() is called when a different slot is
1259 	 * busy transferring data.
1260 	 */
1261 	if (host->need_clock_update) {
1262 		atmci_writel(host, ATMCI_MR, host->mode_reg);
1263 		if (host->caps.has_cfg_reg)
1264 			atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1265 	}
1266 
1267 	host->cur_slot->mrq = NULL;
1268 	host->mrq = NULL;
1269 	if (!list_empty(&host->queue)) {
1270 		slot = list_entry(host->queue.next,
1271 				struct atmel_mci_slot, queue_node);
1272 		list_del(&slot->queue_node);
1273 		dev_vdbg(&host->pdev->dev, "list not empty: %s is next\n",
1274 				mmc_hostname(slot->mmc));
1275 		host->state = STATE_SENDING_CMD;
1276 		atmci_start_request(host, slot);
1277 	} else {
1278 		dev_vdbg(&host->pdev->dev, "list empty\n");
1279 		host->state = STATE_IDLE;
1280 	}
1281 
1282 	spin_unlock(&host->lock);
1283 	mmc_request_done(prev_mmc, mrq);
1284 	spin_lock(&host->lock);
1285 }
1286 
1287 static void atmci_command_complete(struct atmel_mci *host,
1288 			struct mmc_command *cmd)
1289 {
1290 	u32		status = host->cmd_status;
1291 
1292 	/* Read the response from the card (up to 16 bytes) */
1293 	cmd->resp[0] = atmci_readl(host, ATMCI_RSPR);
1294 	cmd->resp[1] = atmci_readl(host, ATMCI_RSPR);
1295 	cmd->resp[2] = atmci_readl(host, ATMCI_RSPR);
1296 	cmd->resp[3] = atmci_readl(host, ATMCI_RSPR);
1297 
1298 	if (status & ATMCI_RTOE)
1299 		cmd->error = -ETIMEDOUT;
1300 	else if ((cmd->flags & MMC_RSP_CRC) && (status & ATMCI_RCRCE))
1301 		cmd->error = -EILSEQ;
1302 	else if (status & (ATMCI_RINDE | ATMCI_RDIRE | ATMCI_RENDE))
1303 		cmd->error = -EIO;
1304 	else
1305 		cmd->error = 0;
1306 
1307 	if (cmd->error) {
1308 		dev_dbg(&host->pdev->dev,
1309 			"command error: status=0x%08x\n", status);
1310 
1311 		if (cmd->data) {
1312 			host->stop_transfer(host);
1313 			host->data = NULL;
1314 			atmci_writel(host, ATMCI_IDR, ATMCI_NOTBUSY
1315 					| ATMCI_TXRDY | ATMCI_RXRDY
1316 					| ATMCI_DATA_ERROR_FLAGS);
1317 		}
1318 	}
1319 }
1320 
1321 static void atmci_detect_change(unsigned long data)
1322 {
1323 	struct atmel_mci_slot	*slot = (struct atmel_mci_slot *)data;
1324 	bool			present;
1325 	bool			present_old;
1326 
1327 	/*
1328 	 * atmci_cleanup_slot() sets the ATMCI_SHUTDOWN flag before
1329 	 * freeing the interrupt. We must not re-enable the interrupt
1330 	 * if it has been freed, and if we're shutting down, it
1331 	 * doesn't really matter whether the card is present or not.
1332 	 */
1333 	smp_rmb();
1334 	if (test_bit(ATMCI_SHUTDOWN, &slot->flags))
1335 		return;
1336 
1337 	enable_irq(gpio_to_irq(slot->detect_pin));
1338 	present = !(gpio_get_value(slot->detect_pin) ^
1339 		    slot->detect_is_active_high);
1340 	present_old = test_bit(ATMCI_CARD_PRESENT, &slot->flags);
1341 
1342 	dev_vdbg(&slot->mmc->class_dev, "detect change: %d (was %d)\n",
1343 			present, present_old);
1344 
1345 	if (present != present_old) {
1346 		struct atmel_mci	*host = slot->host;
1347 		struct mmc_request	*mrq;
1348 
1349 		dev_dbg(&slot->mmc->class_dev, "card %s\n",
1350 			present ? "inserted" : "removed");
1351 
1352 		spin_lock(&host->lock);
1353 
1354 		if (!present)
1355 			clear_bit(ATMCI_CARD_PRESENT, &slot->flags);
1356 		else
1357 			set_bit(ATMCI_CARD_PRESENT, &slot->flags);
1358 
1359 		/* Clean up queue if present */
1360 		mrq = slot->mrq;
1361 		if (mrq) {
1362 			if (mrq == host->mrq) {
1363 				/*
1364 				 * Reset controller to terminate any ongoing
1365 				 * commands or data transfers.
1366 				 */
1367 				atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
1368 				atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
1369 				atmci_writel(host, ATMCI_MR, host->mode_reg);
1370 				if (host->caps.has_cfg_reg)
1371 					atmci_writel(host, ATMCI_CFG, host->cfg_reg);
1372 
1373 				host->data = NULL;
1374 				host->cmd = NULL;
1375 
1376 				switch (host->state) {
1377 				case STATE_IDLE:
1378 					break;
1379 				case STATE_SENDING_CMD:
1380 					mrq->cmd->error = -ENOMEDIUM;
1381 					if (!mrq->data)
1382 						break;
1383 					/* fall through */
1384 				case STATE_SENDING_DATA:
1385 					mrq->data->error = -ENOMEDIUM;
1386 					host->stop_transfer(host);
1387 					break;
1388 				case STATE_DATA_BUSY:
1389 				case STATE_DATA_ERROR:
1390 					if (mrq->data->error == -EINPROGRESS)
1391 						mrq->data->error = -ENOMEDIUM;
1392 					if (!mrq->stop)
1393 						break;
1394 					/* fall through */
1395 				case STATE_SENDING_STOP:
1396 					mrq->stop->error = -ENOMEDIUM;
1397 					break;
1398 				}
1399 
1400 				atmci_request_end(host, mrq);
1401 			} else {
1402 				list_del(&slot->queue_node);
1403 				mrq->cmd->error = -ENOMEDIUM;
1404 				if (mrq->data)
1405 					mrq->data->error = -ENOMEDIUM;
1406 				if (mrq->stop)
1407 					mrq->stop->error = -ENOMEDIUM;
1408 
1409 				spin_unlock(&host->lock);
1410 				mmc_request_done(slot->mmc, mrq);
1411 				spin_lock(&host->lock);
1412 			}
1413 		}
1414 		spin_unlock(&host->lock);
1415 
1416 		mmc_detect_change(slot->mmc, 0);
1417 	}
1418 }
1419 
1420 static void atmci_tasklet_func(unsigned long priv)
1421 {
1422 	struct atmel_mci	*host = (struct atmel_mci *)priv;
1423 	struct mmc_request	*mrq = host->mrq;
1424 	struct mmc_data		*data = host->data;
1425 	struct mmc_command	*cmd = host->cmd;
1426 	enum atmel_mci_state	state = host->state;
1427 	enum atmel_mci_state	prev_state;
1428 	u32			status;
1429 
1430 	spin_lock(&host->lock);
1431 
1432 	state = host->state;
1433 
1434 	dev_vdbg(&host->pdev->dev,
1435 		"tasklet: state %u pending/completed/mask %lx/%lx/%x\n",
1436 		state, host->pending_events, host->completed_events,
1437 		atmci_readl(host, ATMCI_IMR));
1438 
1439 	do {
1440 		prev_state = state;
1441 
1442 		switch (state) {
1443 		case STATE_IDLE:
1444 			break;
1445 
1446 		case STATE_SENDING_CMD:
1447 			if (!atmci_test_and_clear_pending(host,
1448 						EVENT_CMD_COMPLETE))
1449 				break;
1450 
1451 			host->cmd = NULL;
1452 			atmci_set_completed(host, EVENT_CMD_COMPLETE);
1453 			atmci_command_complete(host, mrq->cmd);
1454 			if (!mrq->data || cmd->error) {
1455 				atmci_request_end(host, host->mrq);
1456 				goto unlock;
1457 			}
1458 
1459 			prev_state = state = STATE_SENDING_DATA;
1460 			/* fall through */
1461 
1462 		case STATE_SENDING_DATA:
1463 			if (atmci_test_and_clear_pending(host,
1464 						EVENT_DATA_ERROR)) {
1465 				host->stop_transfer(host);
1466 				if (data->stop)
1467 					atmci_send_stop_cmd(host, data);
1468 				state = STATE_DATA_ERROR;
1469 				break;
1470 			}
1471 
1472 			if (!atmci_test_and_clear_pending(host,
1473 						EVENT_XFER_COMPLETE))
1474 				break;
1475 
1476 			atmci_set_completed(host, EVENT_XFER_COMPLETE);
1477 			prev_state = state = STATE_DATA_BUSY;
1478 			/* fall through */
1479 
1480 		case STATE_DATA_BUSY:
1481 			if (!atmci_test_and_clear_pending(host,
1482 						EVENT_DATA_COMPLETE))
1483 				break;
1484 
1485 			host->data = NULL;
1486 			atmci_set_completed(host, EVENT_DATA_COMPLETE);
1487 			status = host->data_status;
1488 			if (unlikely(status & ATMCI_DATA_ERROR_FLAGS)) {
1489 				if (status & ATMCI_DTOE) {
1490 					dev_dbg(&host->pdev->dev,
1491 							"data timeout error\n");
1492 					data->error = -ETIMEDOUT;
1493 				} else if (status & ATMCI_DCRCE) {
1494 					dev_dbg(&host->pdev->dev,
1495 							"data CRC error\n");
1496 					data->error = -EILSEQ;
1497 				} else {
1498 					dev_dbg(&host->pdev->dev,
1499 						"data FIFO error (status=%08x)\n",
1500 						status);
1501 					data->error = -EIO;
1502 				}
1503 			} else {
1504 				data->bytes_xfered = data->blocks * data->blksz;
1505 				data->error = 0;
1506 				atmci_writel(host, ATMCI_IDR, ATMCI_DATA_ERROR_FLAGS);
1507 			}
1508 
1509 			if (!data->stop) {
1510 				atmci_request_end(host, host->mrq);
1511 				goto unlock;
1512 			}
1513 
1514 			prev_state = state = STATE_SENDING_STOP;
1515 			if (!data->error)
1516 				atmci_send_stop_cmd(host, data);
1517 			/* fall through */
1518 
1519 		case STATE_SENDING_STOP:
1520 			if (!atmci_test_and_clear_pending(host,
1521 						EVENT_CMD_COMPLETE))
1522 				break;
1523 
1524 			host->cmd = NULL;
1525 			atmci_command_complete(host, mrq->stop);
1526 			atmci_request_end(host, host->mrq);
1527 			goto unlock;
1528 
1529 		case STATE_DATA_ERROR:
1530 			if (!atmci_test_and_clear_pending(host,
1531 						EVENT_XFER_COMPLETE))
1532 				break;
1533 
1534 			state = STATE_DATA_BUSY;
1535 			break;
1536 		}
1537 	} while (state != prev_state);
1538 
1539 	host->state = state;
1540 
1541 unlock:
1542 	spin_unlock(&host->lock);
1543 }
1544 
1545 static void atmci_read_data_pio(struct atmel_mci *host)
1546 {
1547 	struct scatterlist	*sg = host->sg;
1548 	void			*buf = sg_virt(sg);
1549 	unsigned int		offset = host->pio_offset;
1550 	struct mmc_data		*data = host->data;
1551 	u32			value;
1552 	u32			status;
1553 	unsigned int		nbytes = 0;
1554 
1555 	do {
1556 		value = atmci_readl(host, ATMCI_RDR);
1557 		if (likely(offset + 4 <= sg->length)) {
1558 			put_unaligned(value, (u32 *)(buf + offset));
1559 
1560 			offset += 4;
1561 			nbytes += 4;
1562 
1563 			if (offset == sg->length) {
1564 				flush_dcache_page(sg_page(sg));
1565 				host->sg = sg = sg_next(sg);
1566 				if (!sg)
1567 					goto done;
1568 
1569 				offset = 0;
1570 				buf = sg_virt(sg);
1571 			}
1572 		} else {
1573 			unsigned int remaining = sg->length - offset;
1574 			memcpy(buf + offset, &value, remaining);
1575 			nbytes += remaining;
1576 
1577 			flush_dcache_page(sg_page(sg));
1578 			host->sg = sg = sg_next(sg);
1579 			if (!sg)
1580 				goto done;
1581 
1582 			offset = 4 - remaining;
1583 			buf = sg_virt(sg);
1584 			memcpy(buf, (u8 *)&value + remaining, offset);
1585 			nbytes += offset;
1586 		}
1587 
1588 		status = atmci_readl(host, ATMCI_SR);
1589 		if (status & ATMCI_DATA_ERROR_FLAGS) {
1590 			atmci_writel(host, ATMCI_IDR, (ATMCI_NOTBUSY | ATMCI_RXRDY
1591 						| ATMCI_DATA_ERROR_FLAGS));
1592 			host->data_status = status;
1593 			data->bytes_xfered += nbytes;
1594 			smp_wmb();
1595 			atmci_set_pending(host, EVENT_DATA_ERROR);
1596 			tasklet_schedule(&host->tasklet);
1597 			return;
1598 		}
1599 	} while (status & ATMCI_RXRDY);
1600 
1601 	host->pio_offset = offset;
1602 	data->bytes_xfered += nbytes;
1603 
1604 	return;
1605 
1606 done:
1607 	atmci_writel(host, ATMCI_IDR, ATMCI_RXRDY);
1608 	atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1609 	data->bytes_xfered += nbytes;
1610 	smp_wmb();
1611 	atmci_set_pending(host, EVENT_XFER_COMPLETE);
1612 }
1613 
1614 static void atmci_write_data_pio(struct atmel_mci *host)
1615 {
1616 	struct scatterlist	*sg = host->sg;
1617 	void			*buf = sg_virt(sg);
1618 	unsigned int		offset = host->pio_offset;
1619 	struct mmc_data		*data = host->data;
1620 	u32			value;
1621 	u32			status;
1622 	unsigned int		nbytes = 0;
1623 
1624 	do {
1625 		if (likely(offset + 4 <= sg->length)) {
1626 			value = get_unaligned((u32 *)(buf + offset));
1627 			atmci_writel(host, ATMCI_TDR, value);
1628 
1629 			offset += 4;
1630 			nbytes += 4;
1631 			if (offset == sg->length) {
1632 				host->sg = sg = sg_next(sg);
1633 				if (!sg)
1634 					goto done;
1635 
1636 				offset = 0;
1637 				buf = sg_virt(sg);
1638 			}
1639 		} else {
1640 			unsigned int remaining = sg->length - offset;
1641 
1642 			value = 0;
1643 			memcpy(&value, buf + offset, remaining);
1644 			nbytes += remaining;
1645 
1646 			host->sg = sg = sg_next(sg);
1647 			if (!sg) {
1648 				atmci_writel(host, ATMCI_TDR, value);
1649 				goto done;
1650 			}
1651 
1652 			offset = 4 - remaining;
1653 			buf = sg_virt(sg);
1654 			memcpy((u8 *)&value + remaining, buf, offset);
1655 			atmci_writel(host, ATMCI_TDR, value);
1656 			nbytes += offset;
1657 		}
1658 
1659 		status = atmci_readl(host, ATMCI_SR);
1660 		if (status & ATMCI_DATA_ERROR_FLAGS) {
1661 			atmci_writel(host, ATMCI_IDR, (ATMCI_NOTBUSY | ATMCI_TXRDY
1662 						| ATMCI_DATA_ERROR_FLAGS));
1663 			host->data_status = status;
1664 			data->bytes_xfered += nbytes;
1665 			smp_wmb();
1666 			atmci_set_pending(host, EVENT_DATA_ERROR);
1667 			tasklet_schedule(&host->tasklet);
1668 			return;
1669 		}
1670 	} while (status & ATMCI_TXRDY);
1671 
1672 	host->pio_offset = offset;
1673 	data->bytes_xfered += nbytes;
1674 
1675 	return;
1676 
1677 done:
1678 	atmci_writel(host, ATMCI_IDR, ATMCI_TXRDY);
1679 	atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
1680 	data->bytes_xfered += nbytes;
1681 	smp_wmb();
1682 	atmci_set_pending(host, EVENT_XFER_COMPLETE);
1683 }
1684 
1685 static void atmci_cmd_interrupt(struct atmel_mci *host, u32 status)
1686 {
1687 	atmci_writel(host, ATMCI_IDR, ATMCI_CMDRDY);
1688 
1689 	host->cmd_status = status;
1690 	smp_wmb();
1691 	atmci_set_pending(host, EVENT_CMD_COMPLETE);
1692 	tasklet_schedule(&host->tasklet);
1693 }
1694 
1695 static void atmci_sdio_interrupt(struct atmel_mci *host, u32 status)
1696 {
1697 	int	i;
1698 
1699 	for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
1700 		struct atmel_mci_slot *slot = host->slot[i];
1701 		if (slot && (status & slot->sdio_irq)) {
1702 			mmc_signal_sdio_irq(slot->mmc);
1703 		}
1704 	}
1705 }
1706 
1707 
1708 static irqreturn_t atmci_interrupt(int irq, void *dev_id)
1709 {
1710 	struct atmel_mci	*host = dev_id;
1711 	u32			status, mask, pending;
1712 	unsigned int		pass_count = 0;
1713 
1714 	do {
1715 		status = atmci_readl(host, ATMCI_SR);
1716 		mask = atmci_readl(host, ATMCI_IMR);
1717 		pending = status & mask;
1718 		if (!pending)
1719 			break;
1720 
1721 		if (pending & ATMCI_DATA_ERROR_FLAGS) {
1722 			atmci_writel(host, ATMCI_IDR, ATMCI_DATA_ERROR_FLAGS
1723 					| ATMCI_RXRDY | ATMCI_TXRDY);
1724 			pending &= atmci_readl(host, ATMCI_IMR);
1725 
1726 			host->data_status = status;
1727 			smp_wmb();
1728 			atmci_set_pending(host, EVENT_DATA_ERROR);
1729 			tasklet_schedule(&host->tasklet);
1730 		}
1731 
1732 		if (pending & ATMCI_TXBUFE) {
1733 			atmci_writel(host, ATMCI_IDR, ATMCI_TXBUFE);
1734 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDTX);
1735 			/*
1736 			 * We can receive this interruption before having configured
1737 			 * the second pdc buffer, so we need to reconfigure first and
1738 			 * second buffers again
1739 			 */
1740 			if (host->data_size) {
1741 				atmci_pdc_set_both_buf(host, XFER_TRANSMIT);
1742 				atmci_writel(host, ATMCI_IER, ATMCI_ENDTX);
1743 				atmci_writel(host, ATMCI_IER, ATMCI_TXBUFE);
1744 			} else {
1745 				atmci_pdc_complete(host);
1746 			}
1747 		} else if (pending & ATMCI_ENDTX) {
1748 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDTX);
1749 
1750 			if (host->data_size) {
1751 				atmci_pdc_set_single_buf(host,
1752 						XFER_TRANSMIT, PDC_SECOND_BUF);
1753 				atmci_writel(host, ATMCI_IER, ATMCI_ENDTX);
1754 			}
1755 		}
1756 
1757 		if (pending & ATMCI_RXBUFF) {
1758 			atmci_writel(host, ATMCI_IDR, ATMCI_RXBUFF);
1759 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDRX);
1760 			/*
1761 			 * We can receive this interruption before having configured
1762 			 * the second pdc buffer, so we need to reconfigure first and
1763 			 * second buffers again
1764 			 */
1765 			if (host->data_size) {
1766 				atmci_pdc_set_both_buf(host, XFER_RECEIVE);
1767 				atmci_writel(host, ATMCI_IER, ATMCI_ENDRX);
1768 				atmci_writel(host, ATMCI_IER, ATMCI_RXBUFF);
1769 			} else {
1770 				atmci_pdc_complete(host);
1771 			}
1772 		} else if (pending & ATMCI_ENDRX) {
1773 			atmci_writel(host, ATMCI_IDR, ATMCI_ENDRX);
1774 
1775 			if (host->data_size) {
1776 				atmci_pdc_set_single_buf(host,
1777 						XFER_RECEIVE, PDC_SECOND_BUF);
1778 				atmci_writel(host, ATMCI_IER, ATMCI_ENDRX);
1779 			}
1780 		}
1781 
1782 
1783 		if (pending & ATMCI_NOTBUSY) {
1784 			atmci_writel(host, ATMCI_IDR,
1785 					ATMCI_DATA_ERROR_FLAGS | ATMCI_NOTBUSY);
1786 			if (!host->data_status)
1787 				host->data_status = status;
1788 			smp_wmb();
1789 			atmci_set_pending(host, EVENT_DATA_COMPLETE);
1790 			tasklet_schedule(&host->tasklet);
1791 		}
1792 		if (pending & ATMCI_RXRDY)
1793 			atmci_read_data_pio(host);
1794 		if (pending & ATMCI_TXRDY)
1795 			atmci_write_data_pio(host);
1796 
1797 		if (pending & ATMCI_CMDRDY)
1798 			atmci_cmd_interrupt(host, status);
1799 
1800 		if (pending & (ATMCI_SDIOIRQA | ATMCI_SDIOIRQB))
1801 			atmci_sdio_interrupt(host, status);
1802 
1803 	} while (pass_count++ < 5);
1804 
1805 	return pass_count ? IRQ_HANDLED : IRQ_NONE;
1806 }
1807 
1808 static irqreturn_t atmci_detect_interrupt(int irq, void *dev_id)
1809 {
1810 	struct atmel_mci_slot	*slot = dev_id;
1811 
1812 	/*
1813 	 * Disable interrupts until the pin has stabilized and check
1814 	 * the state then. Use mod_timer() since we may be in the
1815 	 * middle of the timer routine when this interrupt triggers.
1816 	 */
1817 	disable_irq_nosync(irq);
1818 	mod_timer(&slot->detect_timer, jiffies + msecs_to_jiffies(20));
1819 
1820 	return IRQ_HANDLED;
1821 }
1822 
1823 static int __init atmci_init_slot(struct atmel_mci *host,
1824 		struct mci_slot_pdata *slot_data, unsigned int id,
1825 		u32 sdc_reg, u32 sdio_irq)
1826 {
1827 	struct mmc_host			*mmc;
1828 	struct atmel_mci_slot		*slot;
1829 
1830 	mmc = mmc_alloc_host(sizeof(struct atmel_mci_slot), &host->pdev->dev);
1831 	if (!mmc)
1832 		return -ENOMEM;
1833 
1834 	slot = mmc_priv(mmc);
1835 	slot->mmc = mmc;
1836 	slot->host = host;
1837 	slot->detect_pin = slot_data->detect_pin;
1838 	slot->wp_pin = slot_data->wp_pin;
1839 	slot->detect_is_active_high = slot_data->detect_is_active_high;
1840 	slot->sdc_reg = sdc_reg;
1841 	slot->sdio_irq = sdio_irq;
1842 
1843 	mmc->ops = &atmci_ops;
1844 	mmc->f_min = DIV_ROUND_UP(host->bus_hz, 512);
1845 	mmc->f_max = host->bus_hz / 2;
1846 	mmc->ocr_avail	= MMC_VDD_32_33 | MMC_VDD_33_34;
1847 	if (sdio_irq)
1848 		mmc->caps |= MMC_CAP_SDIO_IRQ;
1849 	if (host->caps.has_highspeed)
1850 		mmc->caps |= MMC_CAP_SD_HIGHSPEED;
1851 	if (slot_data->bus_width >= 4)
1852 		mmc->caps |= MMC_CAP_4_BIT_DATA;
1853 
1854 	mmc->max_segs = 64;
1855 	mmc->max_req_size = 32768 * 512;
1856 	mmc->max_blk_size = 32768;
1857 	mmc->max_blk_count = 512;
1858 
1859 	/* Assume card is present initially */
1860 	set_bit(ATMCI_CARD_PRESENT, &slot->flags);
1861 	if (gpio_is_valid(slot->detect_pin)) {
1862 		if (gpio_request(slot->detect_pin, "mmc_detect")) {
1863 			dev_dbg(&mmc->class_dev, "no detect pin available\n");
1864 			slot->detect_pin = -EBUSY;
1865 		} else if (gpio_get_value(slot->detect_pin) ^
1866 				slot->detect_is_active_high) {
1867 			clear_bit(ATMCI_CARD_PRESENT, &slot->flags);
1868 		}
1869 	}
1870 
1871 	if (!gpio_is_valid(slot->detect_pin))
1872 		mmc->caps |= MMC_CAP_NEEDS_POLL;
1873 
1874 	if (gpio_is_valid(slot->wp_pin)) {
1875 		if (gpio_request(slot->wp_pin, "mmc_wp")) {
1876 			dev_dbg(&mmc->class_dev, "no WP pin available\n");
1877 			slot->wp_pin = -EBUSY;
1878 		}
1879 	}
1880 
1881 	host->slot[id] = slot;
1882 	mmc_add_host(mmc);
1883 
1884 	if (gpio_is_valid(slot->detect_pin)) {
1885 		int ret;
1886 
1887 		setup_timer(&slot->detect_timer, atmci_detect_change,
1888 				(unsigned long)slot);
1889 
1890 		ret = request_irq(gpio_to_irq(slot->detect_pin),
1891 				atmci_detect_interrupt,
1892 				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
1893 				"mmc-detect", slot);
1894 		if (ret) {
1895 			dev_dbg(&mmc->class_dev,
1896 				"could not request IRQ %d for detect pin\n",
1897 				gpio_to_irq(slot->detect_pin));
1898 			gpio_free(slot->detect_pin);
1899 			slot->detect_pin = -EBUSY;
1900 		}
1901 	}
1902 
1903 	atmci_init_debugfs(slot);
1904 
1905 	return 0;
1906 }
1907 
1908 static void __exit atmci_cleanup_slot(struct atmel_mci_slot *slot,
1909 		unsigned int id)
1910 {
1911 	/* Debugfs stuff is cleaned up by mmc core */
1912 
1913 	set_bit(ATMCI_SHUTDOWN, &slot->flags);
1914 	smp_wmb();
1915 
1916 	mmc_remove_host(slot->mmc);
1917 
1918 	if (gpio_is_valid(slot->detect_pin)) {
1919 		int pin = slot->detect_pin;
1920 
1921 		free_irq(gpio_to_irq(pin), slot);
1922 		del_timer_sync(&slot->detect_timer);
1923 		gpio_free(pin);
1924 	}
1925 	if (gpio_is_valid(slot->wp_pin))
1926 		gpio_free(slot->wp_pin);
1927 
1928 	slot->host->slot[id] = NULL;
1929 	mmc_free_host(slot->mmc);
1930 }
1931 
1932 static bool atmci_filter(struct dma_chan *chan, void *slave)
1933 {
1934 	struct mci_dma_data	*sl = slave;
1935 
1936 	if (sl && find_slave_dev(sl) == chan->device->dev) {
1937 		chan->private = slave_data_ptr(sl);
1938 		return true;
1939 	} else {
1940 		return false;
1941 	}
1942 }
1943 
1944 static void atmci_configure_dma(struct atmel_mci *host)
1945 {
1946 	struct mci_platform_data	*pdata;
1947 
1948 	if (host == NULL)
1949 		return;
1950 
1951 	pdata = host->pdev->dev.platform_data;
1952 
1953 	if (pdata && find_slave_dev(pdata->dma_slave)) {
1954 		dma_cap_mask_t mask;
1955 
1956 		setup_dma_addr(pdata->dma_slave,
1957 			       host->mapbase + ATMCI_TDR,
1958 			       host->mapbase + ATMCI_RDR);
1959 
1960 		/* Try to grab a DMA channel */
1961 		dma_cap_zero(mask);
1962 		dma_cap_set(DMA_SLAVE, mask);
1963 		host->dma.chan =
1964 			dma_request_channel(mask, atmci_filter, pdata->dma_slave);
1965 	}
1966 	if (!host->dma.chan)
1967 		dev_notice(&host->pdev->dev, "DMA not available, using PIO\n");
1968 	else
1969 		dev_info(&host->pdev->dev,
1970 					"Using %s for DMA transfers\n",
1971 					dma_chan_name(host->dma.chan));
1972 }
1973 
1974 static inline unsigned int atmci_get_version(struct atmel_mci *host)
1975 {
1976 	return atmci_readl(host, ATMCI_VERSION) & 0x00000fff;
1977 }
1978 
1979 /*
1980  * HSMCI (High Speed MCI) module is not fully compatible with MCI module.
1981  * HSMCI provides DMA support and a new config register but no more supports
1982  * PDC.
1983  */
1984 static void __init atmci_get_cap(struct atmel_mci *host)
1985 {
1986 	unsigned int version;
1987 
1988 	version = atmci_get_version(host);
1989 	dev_info(&host->pdev->dev,
1990 			"version: 0x%x\n", version);
1991 
1992 	host->caps.has_dma = 0;
1993 	host->caps.has_pdc = 0;
1994 	host->caps.has_cfg_reg = 0;
1995 	host->caps.has_cstor_reg = 0;
1996 	host->caps.has_highspeed = 0;
1997 	host->caps.has_rwproof = 0;
1998 
1999 	/* keep only major version number */
2000 	switch (version & 0xf00) {
2001 	case 0x100:
2002 	case 0x200:
2003 		host->caps.has_pdc = 1;
2004 		host->caps.has_rwproof = 1;
2005 		break;
2006 	case 0x300:
2007 	case 0x400:
2008 	case 0x500:
2009 #ifdef CONFIG_AT_HDMAC
2010 		host->caps.has_dma = 1;
2011 #else
2012 		host->caps.has_dma = 0;
2013 		dev_info(&host->pdev->dev,
2014 			"has dma capability but dma engine is not selected, then use pio\n");
2015 #endif
2016 		host->caps.has_cfg_reg = 1;
2017 		host->caps.has_cstor_reg = 1;
2018 		host->caps.has_highspeed = 1;
2019 		host->caps.has_rwproof = 1;
2020 		break;
2021 	default:
2022 		dev_warn(&host->pdev->dev,
2023 				"Unmanaged mci version, set minimum capabilities\n");
2024 		break;
2025 	}
2026 }
2027 
2028 static int __init atmci_probe(struct platform_device *pdev)
2029 {
2030 	struct mci_platform_data	*pdata;
2031 	struct atmel_mci		*host;
2032 	struct resource			*regs;
2033 	unsigned int			nr_slots;
2034 	int				irq;
2035 	int				ret;
2036 
2037 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2038 	if (!regs)
2039 		return -ENXIO;
2040 	pdata = pdev->dev.platform_data;
2041 	if (!pdata)
2042 		return -ENXIO;
2043 	irq = platform_get_irq(pdev, 0);
2044 	if (irq < 0)
2045 		return irq;
2046 
2047 	host = kzalloc(sizeof(struct atmel_mci), GFP_KERNEL);
2048 	if (!host)
2049 		return -ENOMEM;
2050 
2051 	host->pdev = pdev;
2052 	spin_lock_init(&host->lock);
2053 	INIT_LIST_HEAD(&host->queue);
2054 
2055 	host->mck = clk_get(&pdev->dev, "mci_clk");
2056 	if (IS_ERR(host->mck)) {
2057 		ret = PTR_ERR(host->mck);
2058 		goto err_clk_get;
2059 	}
2060 
2061 	ret = -ENOMEM;
2062 	host->regs = ioremap(regs->start, resource_size(regs));
2063 	if (!host->regs)
2064 		goto err_ioremap;
2065 
2066 	clk_enable(host->mck);
2067 	atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
2068 	host->bus_hz = clk_get_rate(host->mck);
2069 	clk_disable(host->mck);
2070 
2071 	host->mapbase = regs->start;
2072 
2073 	tasklet_init(&host->tasklet, atmci_tasklet_func, (unsigned long)host);
2074 
2075 	ret = request_irq(irq, atmci_interrupt, 0, dev_name(&pdev->dev), host);
2076 	if (ret)
2077 		goto err_request_irq;
2078 
2079 	/* Get MCI capabilities and set operations according to it */
2080 	atmci_get_cap(host);
2081 	if (host->caps.has_dma) {
2082 		dev_info(&pdev->dev, "using DMA\n");
2083 		host->prepare_data = &atmci_prepare_data_dma;
2084 		host->submit_data = &atmci_submit_data_dma;
2085 		host->stop_transfer = &atmci_stop_transfer_dma;
2086 	} else if (host->caps.has_pdc) {
2087 		dev_info(&pdev->dev, "using PDC\n");
2088 		host->prepare_data = &atmci_prepare_data_pdc;
2089 		host->submit_data = &atmci_submit_data_pdc;
2090 		host->stop_transfer = &atmci_stop_transfer_pdc;
2091 	} else {
2092 		dev_info(&pdev->dev, "no DMA, no PDC\n");
2093 		host->prepare_data = &atmci_prepare_data;
2094 		host->submit_data = &atmci_submit_data;
2095 		host->stop_transfer = &atmci_stop_transfer;
2096 	}
2097 
2098 	if (host->caps.has_dma)
2099 		atmci_configure_dma(host);
2100 
2101 	platform_set_drvdata(pdev, host);
2102 
2103 	/* We need at least one slot to succeed */
2104 	nr_slots = 0;
2105 	ret = -ENODEV;
2106 	if (pdata->slot[0].bus_width) {
2107 		ret = atmci_init_slot(host, &pdata->slot[0],
2108 				0, ATMCI_SDCSEL_SLOT_A, ATMCI_SDIOIRQA);
2109 		if (!ret)
2110 			nr_slots++;
2111 	}
2112 	if (pdata->slot[1].bus_width) {
2113 		ret = atmci_init_slot(host, &pdata->slot[1],
2114 				1, ATMCI_SDCSEL_SLOT_B, ATMCI_SDIOIRQB);
2115 		if (!ret)
2116 			nr_slots++;
2117 	}
2118 
2119 	if (!nr_slots) {
2120 		dev_err(&pdev->dev, "init failed: no slot defined\n");
2121 		goto err_init_slot;
2122 	}
2123 
2124 	dev_info(&pdev->dev,
2125 			"Atmel MCI controller at 0x%08lx irq %d, %u slots\n",
2126 			host->mapbase, irq, nr_slots);
2127 
2128 	return 0;
2129 
2130 err_init_slot:
2131 	if (host->dma.chan)
2132 		dma_release_channel(host->dma.chan);
2133 	free_irq(irq, host);
2134 err_request_irq:
2135 	iounmap(host->regs);
2136 err_ioremap:
2137 	clk_put(host->mck);
2138 err_clk_get:
2139 	kfree(host);
2140 	return ret;
2141 }
2142 
2143 static int __exit atmci_remove(struct platform_device *pdev)
2144 {
2145 	struct atmel_mci	*host = platform_get_drvdata(pdev);
2146 	unsigned int		i;
2147 
2148 	platform_set_drvdata(pdev, NULL);
2149 
2150 	for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
2151 		if (host->slot[i])
2152 			atmci_cleanup_slot(host->slot[i], i);
2153 	}
2154 
2155 	clk_enable(host->mck);
2156 	atmci_writel(host, ATMCI_IDR, ~0UL);
2157 	atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIDIS);
2158 	atmci_readl(host, ATMCI_SR);
2159 	clk_disable(host->mck);
2160 
2161 #ifdef CONFIG_MMC_ATMELMCI_DMA
2162 	if (host->dma.chan)
2163 		dma_release_channel(host->dma.chan);
2164 #endif
2165 
2166 	free_irq(platform_get_irq(pdev, 0), host);
2167 	iounmap(host->regs);
2168 
2169 	clk_put(host->mck);
2170 	kfree(host);
2171 
2172 	return 0;
2173 }
2174 
2175 #ifdef CONFIG_PM
2176 static int atmci_suspend(struct device *dev)
2177 {
2178 	struct atmel_mci *host = dev_get_drvdata(dev);
2179 	int i;
2180 
2181 	 for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
2182 		struct atmel_mci_slot *slot = host->slot[i];
2183 		int ret;
2184 
2185 		if (!slot)
2186 			continue;
2187 		ret = mmc_suspend_host(slot->mmc);
2188 		if (ret < 0) {
2189 			while (--i >= 0) {
2190 				slot = host->slot[i];
2191 				if (slot
2192 				&& test_bit(ATMCI_SUSPENDED, &slot->flags)) {
2193 					mmc_resume_host(host->slot[i]->mmc);
2194 					clear_bit(ATMCI_SUSPENDED, &slot->flags);
2195 				}
2196 			}
2197 			return ret;
2198 		} else {
2199 			set_bit(ATMCI_SUSPENDED, &slot->flags);
2200 		}
2201 	}
2202 
2203 	return 0;
2204 }
2205 
2206 static int atmci_resume(struct device *dev)
2207 {
2208 	struct atmel_mci *host = dev_get_drvdata(dev);
2209 	int i;
2210 	int ret = 0;
2211 
2212 	for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
2213 		struct atmel_mci_slot *slot = host->slot[i];
2214 		int err;
2215 
2216 		slot = host->slot[i];
2217 		if (!slot)
2218 			continue;
2219 		if (!test_bit(ATMCI_SUSPENDED, &slot->flags))
2220 			continue;
2221 		err = mmc_resume_host(slot->mmc);
2222 		if (err < 0)
2223 			ret = err;
2224 		else
2225 			clear_bit(ATMCI_SUSPENDED, &slot->flags);
2226 	}
2227 
2228 	return ret;
2229 }
2230 static SIMPLE_DEV_PM_OPS(atmci_pm, atmci_suspend, atmci_resume);
2231 #define ATMCI_PM_OPS	(&atmci_pm)
2232 #else
2233 #define ATMCI_PM_OPS	NULL
2234 #endif
2235 
2236 static struct platform_driver atmci_driver = {
2237 	.remove		= __exit_p(atmci_remove),
2238 	.driver		= {
2239 		.name		= "atmel_mci",
2240 		.pm		= ATMCI_PM_OPS,
2241 	},
2242 };
2243 
2244 static int __init atmci_init(void)
2245 {
2246 	return platform_driver_probe(&atmci_driver, atmci_probe);
2247 }
2248 
2249 static void __exit atmci_exit(void)
2250 {
2251 	platform_driver_unregister(&atmci_driver);
2252 }
2253 
2254 late_initcall(atmci_init); /* try to load after dma driver when built-in */
2255 module_exit(atmci_exit);
2256 
2257 MODULE_DESCRIPTION("Atmel Multimedia Card Interface driver");
2258 MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
2259 MODULE_LICENSE("GPL v2");
2260