xref: /openbmc/linux/drivers/mmc/host/wbsd.c (revision 95e9fd10)
1 /*
2  *  linux/drivers/mmc/host/wbsd.c - Winbond W83L51xD SD/MMC driver
3  *
4  *  Copyright (C) 2004-2007 Pierre Ossman, All Rights Reserved.
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 as published by
8  * the Free Software Foundation; either version 2 of the License, or (at
9  * your option) any later version.
10  *
11  *
12  * Warning!
13  *
14  * Changes to the FIFO system should be done with extreme care since
15  * the hardware is full of bugs related to the FIFO. Known issues are:
16  *
17  * - FIFO size field in FSR is always zero.
18  *
19  * - FIFO interrupts tend not to work as they should. Interrupts are
20  *   triggered only for full/empty events, not for threshold values.
21  *
22  * - On APIC systems the FIFO empty interrupt is sometimes lost.
23  */
24 
25 #include <linux/module.h>
26 #include <linux/moduleparam.h>
27 #include <linux/init.h>
28 #include <linux/ioport.h>
29 #include <linux/platform_device.h>
30 #include <linux/interrupt.h>
31 #include <linux/dma-mapping.h>
32 #include <linux/delay.h>
33 #include <linux/pnp.h>
34 #include <linux/highmem.h>
35 #include <linux/mmc/host.h>
36 #include <linux/scatterlist.h>
37 #include <linux/slab.h>
38 
39 #include <asm/io.h>
40 #include <asm/dma.h>
41 
42 #include "wbsd.h"
43 
44 #define DRIVER_NAME "wbsd"
45 
46 #define DBG(x...) \
47 	pr_debug(DRIVER_NAME ": " x)
48 #define DBGF(f, x...) \
49 	pr_debug(DRIVER_NAME " [%s()]: " f, __func__ , ##x)
50 
51 /*
52  * Device resources
53  */
54 
55 #ifdef CONFIG_PNP
56 
57 static const struct pnp_device_id pnp_dev_table[] = {
58 	{ "WEC0517", 0 },
59 	{ "WEC0518", 0 },
60 	{ "", 0 },
61 };
62 
63 MODULE_DEVICE_TABLE(pnp, pnp_dev_table);
64 
65 #endif /* CONFIG_PNP */
66 
67 static const int config_ports[] = { 0x2E, 0x4E };
68 static const int unlock_codes[] = { 0x83, 0x87 };
69 
70 static const int valid_ids[] = {
71 	0x7112,
72 };
73 
74 #ifdef CONFIG_PNP
75 static unsigned int param_nopnp = 0;
76 #else
77 static const unsigned int param_nopnp = 1;
78 #endif
79 static unsigned int param_io = 0x248;
80 static unsigned int param_irq = 6;
81 static int param_dma = 2;
82 
83 /*
84  * Basic functions
85  */
86 
87 static inline void wbsd_unlock_config(struct wbsd_host *host)
88 {
89 	BUG_ON(host->config == 0);
90 
91 	outb(host->unlock_code, host->config);
92 	outb(host->unlock_code, host->config);
93 }
94 
95 static inline void wbsd_lock_config(struct wbsd_host *host)
96 {
97 	BUG_ON(host->config == 0);
98 
99 	outb(LOCK_CODE, host->config);
100 }
101 
102 static inline void wbsd_write_config(struct wbsd_host *host, u8 reg, u8 value)
103 {
104 	BUG_ON(host->config == 0);
105 
106 	outb(reg, host->config);
107 	outb(value, host->config + 1);
108 }
109 
110 static inline u8 wbsd_read_config(struct wbsd_host *host, u8 reg)
111 {
112 	BUG_ON(host->config == 0);
113 
114 	outb(reg, host->config);
115 	return inb(host->config + 1);
116 }
117 
118 static inline void wbsd_write_index(struct wbsd_host *host, u8 index, u8 value)
119 {
120 	outb(index, host->base + WBSD_IDXR);
121 	outb(value, host->base + WBSD_DATAR);
122 }
123 
124 static inline u8 wbsd_read_index(struct wbsd_host *host, u8 index)
125 {
126 	outb(index, host->base + WBSD_IDXR);
127 	return inb(host->base + WBSD_DATAR);
128 }
129 
130 /*
131  * Common routines
132  */
133 
134 static void wbsd_init_device(struct wbsd_host *host)
135 {
136 	u8 setup, ier;
137 
138 	/*
139 	 * Reset chip (SD/MMC part) and fifo.
140 	 */
141 	setup = wbsd_read_index(host, WBSD_IDX_SETUP);
142 	setup |= WBSD_FIFO_RESET | WBSD_SOFT_RESET;
143 	wbsd_write_index(host, WBSD_IDX_SETUP, setup);
144 
145 	/*
146 	 * Set DAT3 to input
147 	 */
148 	setup &= ~WBSD_DAT3_H;
149 	wbsd_write_index(host, WBSD_IDX_SETUP, setup);
150 	host->flags &= ~WBSD_FIGNORE_DETECT;
151 
152 	/*
153 	 * Read back default clock.
154 	 */
155 	host->clk = wbsd_read_index(host, WBSD_IDX_CLK);
156 
157 	/*
158 	 * Power down port.
159 	 */
160 	outb(WBSD_POWER_N, host->base + WBSD_CSR);
161 
162 	/*
163 	 * Set maximum timeout.
164 	 */
165 	wbsd_write_index(host, WBSD_IDX_TAAC, 0x7F);
166 
167 	/*
168 	 * Test for card presence
169 	 */
170 	if (inb(host->base + WBSD_CSR) & WBSD_CARDPRESENT)
171 		host->flags |= WBSD_FCARD_PRESENT;
172 	else
173 		host->flags &= ~WBSD_FCARD_PRESENT;
174 
175 	/*
176 	 * Enable interesting interrupts.
177 	 */
178 	ier = 0;
179 	ier |= WBSD_EINT_CARD;
180 	ier |= WBSD_EINT_FIFO_THRE;
181 	ier |= WBSD_EINT_CRC;
182 	ier |= WBSD_EINT_TIMEOUT;
183 	ier |= WBSD_EINT_TC;
184 
185 	outb(ier, host->base + WBSD_EIR);
186 
187 	/*
188 	 * Clear interrupts.
189 	 */
190 	inb(host->base + WBSD_ISR);
191 }
192 
193 static void wbsd_reset(struct wbsd_host *host)
194 {
195 	u8 setup;
196 
197 	pr_err("%s: Resetting chip\n", mmc_hostname(host->mmc));
198 
199 	/*
200 	 * Soft reset of chip (SD/MMC part).
201 	 */
202 	setup = wbsd_read_index(host, WBSD_IDX_SETUP);
203 	setup |= WBSD_SOFT_RESET;
204 	wbsd_write_index(host, WBSD_IDX_SETUP, setup);
205 }
206 
207 static void wbsd_request_end(struct wbsd_host *host, struct mmc_request *mrq)
208 {
209 	unsigned long dmaflags;
210 
211 	if (host->dma >= 0) {
212 		/*
213 		 * Release ISA DMA controller.
214 		 */
215 		dmaflags = claim_dma_lock();
216 		disable_dma(host->dma);
217 		clear_dma_ff(host->dma);
218 		release_dma_lock(dmaflags);
219 
220 		/*
221 		 * Disable DMA on host.
222 		 */
223 		wbsd_write_index(host, WBSD_IDX_DMA, 0);
224 	}
225 
226 	host->mrq = NULL;
227 
228 	/*
229 	 * MMC layer might call back into the driver so first unlock.
230 	 */
231 	spin_unlock(&host->lock);
232 	mmc_request_done(host->mmc, mrq);
233 	spin_lock(&host->lock);
234 }
235 
236 /*
237  * Scatter/gather functions
238  */
239 
240 static inline void wbsd_init_sg(struct wbsd_host *host, struct mmc_data *data)
241 {
242 	/*
243 	 * Get info. about SG list from data structure.
244 	 */
245 	host->cur_sg = data->sg;
246 	host->num_sg = data->sg_len;
247 
248 	host->offset = 0;
249 	host->remain = host->cur_sg->length;
250 }
251 
252 static inline int wbsd_next_sg(struct wbsd_host *host)
253 {
254 	/*
255 	 * Skip to next SG entry.
256 	 */
257 	host->cur_sg++;
258 	host->num_sg--;
259 
260 	/*
261 	 * Any entries left?
262 	 */
263 	if (host->num_sg > 0) {
264 		host->offset = 0;
265 		host->remain = host->cur_sg->length;
266 	}
267 
268 	return host->num_sg;
269 }
270 
271 static inline char *wbsd_sg_to_buffer(struct wbsd_host *host)
272 {
273 	return sg_virt(host->cur_sg);
274 }
275 
276 static inline void wbsd_sg_to_dma(struct wbsd_host *host, struct mmc_data *data)
277 {
278 	unsigned int len, i;
279 	struct scatterlist *sg;
280 	char *dmabuf = host->dma_buffer;
281 	char *sgbuf;
282 
283 	sg = data->sg;
284 	len = data->sg_len;
285 
286 	for (i = 0; i < len; i++) {
287 		sgbuf = sg_virt(&sg[i]);
288 		memcpy(dmabuf, sgbuf, sg[i].length);
289 		dmabuf += sg[i].length;
290 	}
291 }
292 
293 static inline void wbsd_dma_to_sg(struct wbsd_host *host, struct mmc_data *data)
294 {
295 	unsigned int len, i;
296 	struct scatterlist *sg;
297 	char *dmabuf = host->dma_buffer;
298 	char *sgbuf;
299 
300 	sg = data->sg;
301 	len = data->sg_len;
302 
303 	for (i = 0; i < len; i++) {
304 		sgbuf = sg_virt(&sg[i]);
305 		memcpy(sgbuf, dmabuf, sg[i].length);
306 		dmabuf += sg[i].length;
307 	}
308 }
309 
310 /*
311  * Command handling
312  */
313 
314 static inline void wbsd_get_short_reply(struct wbsd_host *host,
315 					struct mmc_command *cmd)
316 {
317 	/*
318 	 * Correct response type?
319 	 */
320 	if (wbsd_read_index(host, WBSD_IDX_RSPLEN) != WBSD_RSP_SHORT) {
321 		cmd->error = -EILSEQ;
322 		return;
323 	}
324 
325 	cmd->resp[0]  = wbsd_read_index(host, WBSD_IDX_RESP12) << 24;
326 	cmd->resp[0] |= wbsd_read_index(host, WBSD_IDX_RESP13) << 16;
327 	cmd->resp[0] |= wbsd_read_index(host, WBSD_IDX_RESP14) << 8;
328 	cmd->resp[0] |= wbsd_read_index(host, WBSD_IDX_RESP15) << 0;
329 	cmd->resp[1]  = wbsd_read_index(host, WBSD_IDX_RESP16) << 24;
330 }
331 
332 static inline void wbsd_get_long_reply(struct wbsd_host *host,
333 	struct mmc_command *cmd)
334 {
335 	int i;
336 
337 	/*
338 	 * Correct response type?
339 	 */
340 	if (wbsd_read_index(host, WBSD_IDX_RSPLEN) != WBSD_RSP_LONG) {
341 		cmd->error = -EILSEQ;
342 		return;
343 	}
344 
345 	for (i = 0; i < 4; i++) {
346 		cmd->resp[i] =
347 			wbsd_read_index(host, WBSD_IDX_RESP1 + i * 4) << 24;
348 		cmd->resp[i] |=
349 			wbsd_read_index(host, WBSD_IDX_RESP2 + i * 4) << 16;
350 		cmd->resp[i] |=
351 			wbsd_read_index(host, WBSD_IDX_RESP3 + i * 4) << 8;
352 		cmd->resp[i] |=
353 			wbsd_read_index(host, WBSD_IDX_RESP4 + i * 4) << 0;
354 	}
355 }
356 
357 static void wbsd_send_command(struct wbsd_host *host, struct mmc_command *cmd)
358 {
359 	int i;
360 	u8 status, isr;
361 
362 	/*
363 	 * Clear accumulated ISR. The interrupt routine
364 	 * will fill this one with events that occur during
365 	 * transfer.
366 	 */
367 	host->isr = 0;
368 
369 	/*
370 	 * Send the command (CRC calculated by host).
371 	 */
372 	outb(cmd->opcode, host->base + WBSD_CMDR);
373 	for (i = 3; i >= 0; i--)
374 		outb((cmd->arg >> (i * 8)) & 0xff, host->base + WBSD_CMDR);
375 
376 	cmd->error = 0;
377 
378 	/*
379 	 * Wait for the request to complete.
380 	 */
381 	do {
382 		status = wbsd_read_index(host, WBSD_IDX_STATUS);
383 	} while (status & WBSD_CARDTRAFFIC);
384 
385 	/*
386 	 * Do we expect a reply?
387 	 */
388 	if (cmd->flags & MMC_RSP_PRESENT) {
389 		/*
390 		 * Read back status.
391 		 */
392 		isr = host->isr;
393 
394 		/* Card removed? */
395 		if (isr & WBSD_INT_CARD)
396 			cmd->error = -ENOMEDIUM;
397 		/* Timeout? */
398 		else if (isr & WBSD_INT_TIMEOUT)
399 			cmd->error = -ETIMEDOUT;
400 		/* CRC? */
401 		else if ((cmd->flags & MMC_RSP_CRC) && (isr & WBSD_INT_CRC))
402 			cmd->error = -EILSEQ;
403 		/* All ok */
404 		else {
405 			if (cmd->flags & MMC_RSP_136)
406 				wbsd_get_long_reply(host, cmd);
407 			else
408 				wbsd_get_short_reply(host, cmd);
409 		}
410 	}
411 }
412 
413 /*
414  * Data functions
415  */
416 
417 static void wbsd_empty_fifo(struct wbsd_host *host)
418 {
419 	struct mmc_data *data = host->mrq->cmd->data;
420 	char *buffer;
421 	int i, fsr, fifo;
422 
423 	/*
424 	 * Handle excessive data.
425 	 */
426 	if (host->num_sg == 0)
427 		return;
428 
429 	buffer = wbsd_sg_to_buffer(host) + host->offset;
430 
431 	/*
432 	 * Drain the fifo. This has a tendency to loop longer
433 	 * than the FIFO length (usually one block).
434 	 */
435 	while (!((fsr = inb(host->base + WBSD_FSR)) & WBSD_FIFO_EMPTY)) {
436 		/*
437 		 * The size field in the FSR is broken so we have to
438 		 * do some guessing.
439 		 */
440 		if (fsr & WBSD_FIFO_FULL)
441 			fifo = 16;
442 		else if (fsr & WBSD_FIFO_FUTHRE)
443 			fifo = 8;
444 		else
445 			fifo = 1;
446 
447 		for (i = 0; i < fifo; i++) {
448 			*buffer = inb(host->base + WBSD_DFR);
449 			buffer++;
450 			host->offset++;
451 			host->remain--;
452 
453 			data->bytes_xfered++;
454 
455 			/*
456 			 * End of scatter list entry?
457 			 */
458 			if (host->remain == 0) {
459 				/*
460 				 * Get next entry. Check if last.
461 				 */
462 				if (!wbsd_next_sg(host))
463 					return;
464 
465 				buffer = wbsd_sg_to_buffer(host);
466 			}
467 		}
468 	}
469 
470 	/*
471 	 * This is a very dirty hack to solve a
472 	 * hardware problem. The chip doesn't trigger
473 	 * FIFO threshold interrupts properly.
474 	 */
475 	if ((data->blocks * data->blksz - data->bytes_xfered) < 16)
476 		tasklet_schedule(&host->fifo_tasklet);
477 }
478 
479 static void wbsd_fill_fifo(struct wbsd_host *host)
480 {
481 	struct mmc_data *data = host->mrq->cmd->data;
482 	char *buffer;
483 	int i, fsr, fifo;
484 
485 	/*
486 	 * Check that we aren't being called after the
487 	 * entire buffer has been transferred.
488 	 */
489 	if (host->num_sg == 0)
490 		return;
491 
492 	buffer = wbsd_sg_to_buffer(host) + host->offset;
493 
494 	/*
495 	 * Fill the fifo. This has a tendency to loop longer
496 	 * than the FIFO length (usually one block).
497 	 */
498 	while (!((fsr = inb(host->base + WBSD_FSR)) & WBSD_FIFO_FULL)) {
499 		/*
500 		 * The size field in the FSR is broken so we have to
501 		 * do some guessing.
502 		 */
503 		if (fsr & WBSD_FIFO_EMPTY)
504 			fifo = 0;
505 		else if (fsr & WBSD_FIFO_EMTHRE)
506 			fifo = 8;
507 		else
508 			fifo = 15;
509 
510 		for (i = 16; i > fifo; i--) {
511 			outb(*buffer, host->base + WBSD_DFR);
512 			buffer++;
513 			host->offset++;
514 			host->remain--;
515 
516 			data->bytes_xfered++;
517 
518 			/*
519 			 * End of scatter list entry?
520 			 */
521 			if (host->remain == 0) {
522 				/*
523 				 * Get next entry. Check if last.
524 				 */
525 				if (!wbsd_next_sg(host))
526 					return;
527 
528 				buffer = wbsd_sg_to_buffer(host);
529 			}
530 		}
531 	}
532 
533 	/*
534 	 * The controller stops sending interrupts for
535 	 * 'FIFO empty' under certain conditions. So we
536 	 * need to be a bit more pro-active.
537 	 */
538 	tasklet_schedule(&host->fifo_tasklet);
539 }
540 
541 static void wbsd_prepare_data(struct wbsd_host *host, struct mmc_data *data)
542 {
543 	u16 blksize;
544 	u8 setup;
545 	unsigned long dmaflags;
546 	unsigned int size;
547 
548 	/*
549 	 * Calculate size.
550 	 */
551 	size = data->blocks * data->blksz;
552 
553 	/*
554 	 * Check timeout values for overflow.
555 	 * (Yes, some cards cause this value to overflow).
556 	 */
557 	if (data->timeout_ns > 127000000)
558 		wbsd_write_index(host, WBSD_IDX_TAAC, 127);
559 	else {
560 		wbsd_write_index(host, WBSD_IDX_TAAC,
561 			data->timeout_ns / 1000000);
562 	}
563 
564 	if (data->timeout_clks > 255)
565 		wbsd_write_index(host, WBSD_IDX_NSAC, 255);
566 	else
567 		wbsd_write_index(host, WBSD_IDX_NSAC, data->timeout_clks);
568 
569 	/*
570 	 * Inform the chip of how large blocks will be
571 	 * sent. It needs this to determine when to
572 	 * calculate CRC.
573 	 *
574 	 * Space for CRC must be included in the size.
575 	 * Two bytes are needed for each data line.
576 	 */
577 	if (host->bus_width == MMC_BUS_WIDTH_1) {
578 		blksize = data->blksz + 2;
579 
580 		wbsd_write_index(host, WBSD_IDX_PBSMSB, (blksize >> 4) & 0xF0);
581 		wbsd_write_index(host, WBSD_IDX_PBSLSB, blksize & 0xFF);
582 	} else if (host->bus_width == MMC_BUS_WIDTH_4) {
583 		blksize = data->blksz + 2 * 4;
584 
585 		wbsd_write_index(host, WBSD_IDX_PBSMSB,
586 			((blksize >> 4) & 0xF0) | WBSD_DATA_WIDTH);
587 		wbsd_write_index(host, WBSD_IDX_PBSLSB, blksize & 0xFF);
588 	} else {
589 		data->error = -EINVAL;
590 		return;
591 	}
592 
593 	/*
594 	 * Clear the FIFO. This is needed even for DMA
595 	 * transfers since the chip still uses the FIFO
596 	 * internally.
597 	 */
598 	setup = wbsd_read_index(host, WBSD_IDX_SETUP);
599 	setup |= WBSD_FIFO_RESET;
600 	wbsd_write_index(host, WBSD_IDX_SETUP, setup);
601 
602 	/*
603 	 * DMA transfer?
604 	 */
605 	if (host->dma >= 0) {
606 		/*
607 		 * The buffer for DMA is only 64 kB.
608 		 */
609 		BUG_ON(size > 0x10000);
610 		if (size > 0x10000) {
611 			data->error = -EINVAL;
612 			return;
613 		}
614 
615 		/*
616 		 * Transfer data from the SG list to
617 		 * the DMA buffer.
618 		 */
619 		if (data->flags & MMC_DATA_WRITE)
620 			wbsd_sg_to_dma(host, data);
621 
622 		/*
623 		 * Initialise the ISA DMA controller.
624 		 */
625 		dmaflags = claim_dma_lock();
626 		disable_dma(host->dma);
627 		clear_dma_ff(host->dma);
628 		if (data->flags & MMC_DATA_READ)
629 			set_dma_mode(host->dma, DMA_MODE_READ & ~0x40);
630 		else
631 			set_dma_mode(host->dma, DMA_MODE_WRITE & ~0x40);
632 		set_dma_addr(host->dma, host->dma_addr);
633 		set_dma_count(host->dma, size);
634 
635 		enable_dma(host->dma);
636 		release_dma_lock(dmaflags);
637 
638 		/*
639 		 * Enable DMA on the host.
640 		 */
641 		wbsd_write_index(host, WBSD_IDX_DMA, WBSD_DMA_ENABLE);
642 	} else {
643 		/*
644 		 * This flag is used to keep printk
645 		 * output to a minimum.
646 		 */
647 		host->firsterr = 1;
648 
649 		/*
650 		 * Initialise the SG list.
651 		 */
652 		wbsd_init_sg(host, data);
653 
654 		/*
655 		 * Turn off DMA.
656 		 */
657 		wbsd_write_index(host, WBSD_IDX_DMA, 0);
658 
659 		/*
660 		 * Set up FIFO threshold levels (and fill
661 		 * buffer if doing a write).
662 		 */
663 		if (data->flags & MMC_DATA_READ) {
664 			wbsd_write_index(host, WBSD_IDX_FIFOEN,
665 				WBSD_FIFOEN_FULL | 8);
666 		} else {
667 			wbsd_write_index(host, WBSD_IDX_FIFOEN,
668 				WBSD_FIFOEN_EMPTY | 8);
669 			wbsd_fill_fifo(host);
670 		}
671 	}
672 
673 	data->error = 0;
674 }
675 
676 static void wbsd_finish_data(struct wbsd_host *host, struct mmc_data *data)
677 {
678 	unsigned long dmaflags;
679 	int count;
680 	u8 status;
681 
682 	WARN_ON(host->mrq == NULL);
683 
684 	/*
685 	 * Send a stop command if needed.
686 	 */
687 	if (data->stop)
688 		wbsd_send_command(host, data->stop);
689 
690 	/*
691 	 * Wait for the controller to leave data
692 	 * transfer state.
693 	 */
694 	do {
695 		status = wbsd_read_index(host, WBSD_IDX_STATUS);
696 	} while (status & (WBSD_BLOCK_READ | WBSD_BLOCK_WRITE));
697 
698 	/*
699 	 * DMA transfer?
700 	 */
701 	if (host->dma >= 0) {
702 		/*
703 		 * Disable DMA on the host.
704 		 */
705 		wbsd_write_index(host, WBSD_IDX_DMA, 0);
706 
707 		/*
708 		 * Turn of ISA DMA controller.
709 		 */
710 		dmaflags = claim_dma_lock();
711 		disable_dma(host->dma);
712 		clear_dma_ff(host->dma);
713 		count = get_dma_residue(host->dma);
714 		release_dma_lock(dmaflags);
715 
716 		data->bytes_xfered = host->mrq->data->blocks *
717 			host->mrq->data->blksz - count;
718 		data->bytes_xfered -= data->bytes_xfered % data->blksz;
719 
720 		/*
721 		 * Any leftover data?
722 		 */
723 		if (count) {
724 			pr_err("%s: Incomplete DMA transfer. "
725 				"%d bytes left.\n",
726 				mmc_hostname(host->mmc), count);
727 
728 			if (!data->error)
729 				data->error = -EIO;
730 		} else {
731 			/*
732 			 * Transfer data from DMA buffer to
733 			 * SG list.
734 			 */
735 			if (data->flags & MMC_DATA_READ)
736 				wbsd_dma_to_sg(host, data);
737 		}
738 
739 		if (data->error) {
740 			if (data->bytes_xfered)
741 				data->bytes_xfered -= data->blksz;
742 		}
743 	}
744 
745 	wbsd_request_end(host, host->mrq);
746 }
747 
748 /*****************************************************************************\
749  *                                                                           *
750  * MMC layer callbacks                                                       *
751  *                                                                           *
752 \*****************************************************************************/
753 
754 static void wbsd_request(struct mmc_host *mmc, struct mmc_request *mrq)
755 {
756 	struct wbsd_host *host = mmc_priv(mmc);
757 	struct mmc_command *cmd;
758 
759 	/*
760 	 * Disable tasklets to avoid a deadlock.
761 	 */
762 	spin_lock_bh(&host->lock);
763 
764 	BUG_ON(host->mrq != NULL);
765 
766 	cmd = mrq->cmd;
767 
768 	host->mrq = mrq;
769 
770 	/*
771 	 * Check that there is actually a card in the slot.
772 	 */
773 	if (!(host->flags & WBSD_FCARD_PRESENT)) {
774 		cmd->error = -ENOMEDIUM;
775 		goto done;
776 	}
777 
778 	if (cmd->data) {
779 		/*
780 		 * The hardware is so delightfully stupid that it has a list
781 		 * of "data" commands. If a command isn't on this list, it'll
782 		 * just go back to the idle state and won't send any data
783 		 * interrupts.
784 		 */
785 		switch (cmd->opcode) {
786 		case 11:
787 		case 17:
788 		case 18:
789 		case 20:
790 		case 24:
791 		case 25:
792 		case 26:
793 		case 27:
794 		case 30:
795 		case 42:
796 		case 56:
797 			break;
798 
799 		/* ACMDs. We don't keep track of state, so we just treat them
800 		 * like any other command. */
801 		case 51:
802 			break;
803 
804 		default:
805 #ifdef CONFIG_MMC_DEBUG
806 			pr_warning("%s: Data command %d is not "
807 				"supported by this controller.\n",
808 				mmc_hostname(host->mmc), cmd->opcode);
809 #endif
810 			cmd->error = -EINVAL;
811 
812 			goto done;
813 		};
814 	}
815 
816 	/*
817 	 * Does the request include data?
818 	 */
819 	if (cmd->data) {
820 		wbsd_prepare_data(host, cmd->data);
821 
822 		if (cmd->data->error)
823 			goto done;
824 	}
825 
826 	wbsd_send_command(host, cmd);
827 
828 	/*
829 	 * If this is a data transfer the request
830 	 * will be finished after the data has
831 	 * transferred.
832 	 */
833 	if (cmd->data && !cmd->error) {
834 		/*
835 		 * Dirty fix for hardware bug.
836 		 */
837 		if (host->dma == -1)
838 			tasklet_schedule(&host->fifo_tasklet);
839 
840 		spin_unlock_bh(&host->lock);
841 
842 		return;
843 	}
844 
845 done:
846 	wbsd_request_end(host, mrq);
847 
848 	spin_unlock_bh(&host->lock);
849 }
850 
851 static void wbsd_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
852 {
853 	struct wbsd_host *host = mmc_priv(mmc);
854 	u8 clk, setup, pwr;
855 
856 	spin_lock_bh(&host->lock);
857 
858 	/*
859 	 * Reset the chip on each power off.
860 	 * Should clear out any weird states.
861 	 */
862 	if (ios->power_mode == MMC_POWER_OFF)
863 		wbsd_init_device(host);
864 
865 	if (ios->clock >= 24000000)
866 		clk = WBSD_CLK_24M;
867 	else if (ios->clock >= 16000000)
868 		clk = WBSD_CLK_16M;
869 	else if (ios->clock >= 12000000)
870 		clk = WBSD_CLK_12M;
871 	else
872 		clk = WBSD_CLK_375K;
873 
874 	/*
875 	 * Only write to the clock register when
876 	 * there is an actual change.
877 	 */
878 	if (clk != host->clk) {
879 		wbsd_write_index(host, WBSD_IDX_CLK, clk);
880 		host->clk = clk;
881 	}
882 
883 	/*
884 	 * Power up card.
885 	 */
886 	if (ios->power_mode != MMC_POWER_OFF) {
887 		pwr = inb(host->base + WBSD_CSR);
888 		pwr &= ~WBSD_POWER_N;
889 		outb(pwr, host->base + WBSD_CSR);
890 	}
891 
892 	/*
893 	 * MMC cards need to have pin 1 high during init.
894 	 * It wreaks havoc with the card detection though so
895 	 * that needs to be disabled.
896 	 */
897 	setup = wbsd_read_index(host, WBSD_IDX_SETUP);
898 	if (ios->chip_select == MMC_CS_HIGH) {
899 		BUG_ON(ios->bus_width != MMC_BUS_WIDTH_1);
900 		setup |= WBSD_DAT3_H;
901 		host->flags |= WBSD_FIGNORE_DETECT;
902 	} else {
903 		if (setup & WBSD_DAT3_H) {
904 			setup &= ~WBSD_DAT3_H;
905 
906 			/*
907 			 * We cannot resume card detection immediately
908 			 * because of capacitance and delays in the chip.
909 			 */
910 			mod_timer(&host->ignore_timer, jiffies + HZ / 100);
911 		}
912 	}
913 	wbsd_write_index(host, WBSD_IDX_SETUP, setup);
914 
915 	/*
916 	 * Store bus width for later. Will be used when
917 	 * setting up the data transfer.
918 	 */
919 	host->bus_width = ios->bus_width;
920 
921 	spin_unlock_bh(&host->lock);
922 }
923 
924 static int wbsd_get_ro(struct mmc_host *mmc)
925 {
926 	struct wbsd_host *host = mmc_priv(mmc);
927 	u8 csr;
928 
929 	spin_lock_bh(&host->lock);
930 
931 	csr = inb(host->base + WBSD_CSR);
932 	csr |= WBSD_MSLED;
933 	outb(csr, host->base + WBSD_CSR);
934 
935 	mdelay(1);
936 
937 	csr = inb(host->base + WBSD_CSR);
938 	csr &= ~WBSD_MSLED;
939 	outb(csr, host->base + WBSD_CSR);
940 
941 	spin_unlock_bh(&host->lock);
942 
943 	return !!(csr & WBSD_WRPT);
944 }
945 
946 static const struct mmc_host_ops wbsd_ops = {
947 	.request	= wbsd_request,
948 	.set_ios	= wbsd_set_ios,
949 	.get_ro		= wbsd_get_ro,
950 };
951 
952 /*****************************************************************************\
953  *                                                                           *
954  * Interrupt handling                                                        *
955  *                                                                           *
956 \*****************************************************************************/
957 
958 /*
959  * Helper function to reset detection ignore
960  */
961 
962 static void wbsd_reset_ignore(unsigned long data)
963 {
964 	struct wbsd_host *host = (struct wbsd_host *)data;
965 
966 	BUG_ON(host == NULL);
967 
968 	DBG("Resetting card detection ignore\n");
969 
970 	spin_lock_bh(&host->lock);
971 
972 	host->flags &= ~WBSD_FIGNORE_DETECT;
973 
974 	/*
975 	 * Card status might have changed during the
976 	 * blackout.
977 	 */
978 	tasklet_schedule(&host->card_tasklet);
979 
980 	spin_unlock_bh(&host->lock);
981 }
982 
983 /*
984  * Tasklets
985  */
986 
987 static inline struct mmc_data *wbsd_get_data(struct wbsd_host *host)
988 {
989 	WARN_ON(!host->mrq);
990 	if (!host->mrq)
991 		return NULL;
992 
993 	WARN_ON(!host->mrq->cmd);
994 	if (!host->mrq->cmd)
995 		return NULL;
996 
997 	WARN_ON(!host->mrq->cmd->data);
998 	if (!host->mrq->cmd->data)
999 		return NULL;
1000 
1001 	return host->mrq->cmd->data;
1002 }
1003 
1004 static void wbsd_tasklet_card(unsigned long param)
1005 {
1006 	struct wbsd_host *host = (struct wbsd_host *)param;
1007 	u8 csr;
1008 	int delay = -1;
1009 
1010 	spin_lock(&host->lock);
1011 
1012 	if (host->flags & WBSD_FIGNORE_DETECT) {
1013 		spin_unlock(&host->lock);
1014 		return;
1015 	}
1016 
1017 	csr = inb(host->base + WBSD_CSR);
1018 	WARN_ON(csr == 0xff);
1019 
1020 	if (csr & WBSD_CARDPRESENT) {
1021 		if (!(host->flags & WBSD_FCARD_PRESENT)) {
1022 			DBG("Card inserted\n");
1023 			host->flags |= WBSD_FCARD_PRESENT;
1024 
1025 			delay = 500;
1026 		}
1027 	} else if (host->flags & WBSD_FCARD_PRESENT) {
1028 		DBG("Card removed\n");
1029 		host->flags &= ~WBSD_FCARD_PRESENT;
1030 
1031 		if (host->mrq) {
1032 			pr_err("%s: Card removed during transfer!\n",
1033 				mmc_hostname(host->mmc));
1034 			wbsd_reset(host);
1035 
1036 			host->mrq->cmd->error = -ENOMEDIUM;
1037 			tasklet_schedule(&host->finish_tasklet);
1038 		}
1039 
1040 		delay = 0;
1041 	}
1042 
1043 	/*
1044 	 * Unlock first since we might get a call back.
1045 	 */
1046 
1047 	spin_unlock(&host->lock);
1048 
1049 	if (delay != -1)
1050 		mmc_detect_change(host->mmc, msecs_to_jiffies(delay));
1051 }
1052 
1053 static void wbsd_tasklet_fifo(unsigned long param)
1054 {
1055 	struct wbsd_host *host = (struct wbsd_host *)param;
1056 	struct mmc_data *data;
1057 
1058 	spin_lock(&host->lock);
1059 
1060 	if (!host->mrq)
1061 		goto end;
1062 
1063 	data = wbsd_get_data(host);
1064 	if (!data)
1065 		goto end;
1066 
1067 	if (data->flags & MMC_DATA_WRITE)
1068 		wbsd_fill_fifo(host);
1069 	else
1070 		wbsd_empty_fifo(host);
1071 
1072 	/*
1073 	 * Done?
1074 	 */
1075 	if (host->num_sg == 0) {
1076 		wbsd_write_index(host, WBSD_IDX_FIFOEN, 0);
1077 		tasklet_schedule(&host->finish_tasklet);
1078 	}
1079 
1080 end:
1081 	spin_unlock(&host->lock);
1082 }
1083 
1084 static void wbsd_tasklet_crc(unsigned long param)
1085 {
1086 	struct wbsd_host *host = (struct wbsd_host *)param;
1087 	struct mmc_data *data;
1088 
1089 	spin_lock(&host->lock);
1090 
1091 	if (!host->mrq)
1092 		goto end;
1093 
1094 	data = wbsd_get_data(host);
1095 	if (!data)
1096 		goto end;
1097 
1098 	DBGF("CRC error\n");
1099 
1100 	data->error = -EILSEQ;
1101 
1102 	tasklet_schedule(&host->finish_tasklet);
1103 
1104 end:
1105 	spin_unlock(&host->lock);
1106 }
1107 
1108 static void wbsd_tasklet_timeout(unsigned long param)
1109 {
1110 	struct wbsd_host *host = (struct wbsd_host *)param;
1111 	struct mmc_data *data;
1112 
1113 	spin_lock(&host->lock);
1114 
1115 	if (!host->mrq)
1116 		goto end;
1117 
1118 	data = wbsd_get_data(host);
1119 	if (!data)
1120 		goto end;
1121 
1122 	DBGF("Timeout\n");
1123 
1124 	data->error = -ETIMEDOUT;
1125 
1126 	tasklet_schedule(&host->finish_tasklet);
1127 
1128 end:
1129 	spin_unlock(&host->lock);
1130 }
1131 
1132 static void wbsd_tasklet_finish(unsigned long param)
1133 {
1134 	struct wbsd_host *host = (struct wbsd_host *)param;
1135 	struct mmc_data *data;
1136 
1137 	spin_lock(&host->lock);
1138 
1139 	WARN_ON(!host->mrq);
1140 	if (!host->mrq)
1141 		goto end;
1142 
1143 	data = wbsd_get_data(host);
1144 	if (!data)
1145 		goto end;
1146 
1147 	wbsd_finish_data(host, data);
1148 
1149 end:
1150 	spin_unlock(&host->lock);
1151 }
1152 
1153 /*
1154  * Interrupt handling
1155  */
1156 
1157 static irqreturn_t wbsd_irq(int irq, void *dev_id)
1158 {
1159 	struct wbsd_host *host = dev_id;
1160 	int isr;
1161 
1162 	isr = inb(host->base + WBSD_ISR);
1163 
1164 	/*
1165 	 * Was it actually our hardware that caused the interrupt?
1166 	 */
1167 	if (isr == 0xff || isr == 0x00)
1168 		return IRQ_NONE;
1169 
1170 	host->isr |= isr;
1171 
1172 	/*
1173 	 * Schedule tasklets as needed.
1174 	 */
1175 	if (isr & WBSD_INT_CARD)
1176 		tasklet_schedule(&host->card_tasklet);
1177 	if (isr & WBSD_INT_FIFO_THRE)
1178 		tasklet_schedule(&host->fifo_tasklet);
1179 	if (isr & WBSD_INT_CRC)
1180 		tasklet_hi_schedule(&host->crc_tasklet);
1181 	if (isr & WBSD_INT_TIMEOUT)
1182 		tasklet_hi_schedule(&host->timeout_tasklet);
1183 	if (isr & WBSD_INT_TC)
1184 		tasklet_schedule(&host->finish_tasklet);
1185 
1186 	return IRQ_HANDLED;
1187 }
1188 
1189 /*****************************************************************************\
1190  *                                                                           *
1191  * Device initialisation and shutdown                                        *
1192  *                                                                           *
1193 \*****************************************************************************/
1194 
1195 /*
1196  * Allocate/free MMC structure.
1197  */
1198 
1199 static int __devinit wbsd_alloc_mmc(struct device *dev)
1200 {
1201 	struct mmc_host *mmc;
1202 	struct wbsd_host *host;
1203 
1204 	/*
1205 	 * Allocate MMC structure.
1206 	 */
1207 	mmc = mmc_alloc_host(sizeof(struct wbsd_host), dev);
1208 	if (!mmc)
1209 		return -ENOMEM;
1210 
1211 	host = mmc_priv(mmc);
1212 	host->mmc = mmc;
1213 
1214 	host->dma = -1;
1215 
1216 	/*
1217 	 * Set host parameters.
1218 	 */
1219 	mmc->ops = &wbsd_ops;
1220 	mmc->f_min = 375000;
1221 	mmc->f_max = 24000000;
1222 	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
1223 	mmc->caps = MMC_CAP_4_BIT_DATA;
1224 
1225 	spin_lock_init(&host->lock);
1226 
1227 	/*
1228 	 * Set up timers
1229 	 */
1230 	init_timer(&host->ignore_timer);
1231 	host->ignore_timer.data = (unsigned long)host;
1232 	host->ignore_timer.function = wbsd_reset_ignore;
1233 
1234 	/*
1235 	 * Maximum number of segments. Worst case is one sector per segment
1236 	 * so this will be 64kB/512.
1237 	 */
1238 	mmc->max_segs = 128;
1239 
1240 	/*
1241 	 * Maximum request size. Also limited by 64KiB buffer.
1242 	 */
1243 	mmc->max_req_size = 65536;
1244 
1245 	/*
1246 	 * Maximum segment size. Could be one segment with the maximum number
1247 	 * of bytes.
1248 	 */
1249 	mmc->max_seg_size = mmc->max_req_size;
1250 
1251 	/*
1252 	 * Maximum block size. We have 12 bits (= 4095) but have to subtract
1253 	 * space for CRC. So the maximum is 4095 - 4*2 = 4087.
1254 	 */
1255 	mmc->max_blk_size = 4087;
1256 
1257 	/*
1258 	 * Maximum block count. There is no real limit so the maximum
1259 	 * request size will be the only restriction.
1260 	 */
1261 	mmc->max_blk_count = mmc->max_req_size;
1262 
1263 	dev_set_drvdata(dev, mmc);
1264 
1265 	return 0;
1266 }
1267 
1268 static void wbsd_free_mmc(struct device *dev)
1269 {
1270 	struct mmc_host *mmc;
1271 	struct wbsd_host *host;
1272 
1273 	mmc = dev_get_drvdata(dev);
1274 	if (!mmc)
1275 		return;
1276 
1277 	host = mmc_priv(mmc);
1278 	BUG_ON(host == NULL);
1279 
1280 	del_timer_sync(&host->ignore_timer);
1281 
1282 	mmc_free_host(mmc);
1283 
1284 	dev_set_drvdata(dev, NULL);
1285 }
1286 
1287 /*
1288  * Scan for known chip id:s
1289  */
1290 
1291 static int __devinit wbsd_scan(struct wbsd_host *host)
1292 {
1293 	int i, j, k;
1294 	int id;
1295 
1296 	/*
1297 	 * Iterate through all ports, all codes to
1298 	 * find hardware that is in our known list.
1299 	 */
1300 	for (i = 0; i < ARRAY_SIZE(config_ports); i++) {
1301 		if (!request_region(config_ports[i], 2, DRIVER_NAME))
1302 			continue;
1303 
1304 		for (j = 0; j < ARRAY_SIZE(unlock_codes); j++) {
1305 			id = 0xFFFF;
1306 
1307 			host->config = config_ports[i];
1308 			host->unlock_code = unlock_codes[j];
1309 
1310 			wbsd_unlock_config(host);
1311 
1312 			outb(WBSD_CONF_ID_HI, config_ports[i]);
1313 			id = inb(config_ports[i] + 1) << 8;
1314 
1315 			outb(WBSD_CONF_ID_LO, config_ports[i]);
1316 			id |= inb(config_ports[i] + 1);
1317 
1318 			wbsd_lock_config(host);
1319 
1320 			for (k = 0; k < ARRAY_SIZE(valid_ids); k++) {
1321 				if (id == valid_ids[k]) {
1322 					host->chip_id = id;
1323 
1324 					return 0;
1325 				}
1326 			}
1327 
1328 			if (id != 0xFFFF) {
1329 				DBG("Unknown hardware (id %x) found at %x\n",
1330 					id, config_ports[i]);
1331 			}
1332 		}
1333 
1334 		release_region(config_ports[i], 2);
1335 	}
1336 
1337 	host->config = 0;
1338 	host->unlock_code = 0;
1339 
1340 	return -ENODEV;
1341 }
1342 
1343 /*
1344  * Allocate/free io port ranges
1345  */
1346 
1347 static int __devinit wbsd_request_region(struct wbsd_host *host, int base)
1348 {
1349 	if (base & 0x7)
1350 		return -EINVAL;
1351 
1352 	if (!request_region(base, 8, DRIVER_NAME))
1353 		return -EIO;
1354 
1355 	host->base = base;
1356 
1357 	return 0;
1358 }
1359 
1360 static void wbsd_release_regions(struct wbsd_host *host)
1361 {
1362 	if (host->base)
1363 		release_region(host->base, 8);
1364 
1365 	host->base = 0;
1366 
1367 	if (host->config)
1368 		release_region(host->config, 2);
1369 
1370 	host->config = 0;
1371 }
1372 
1373 /*
1374  * Allocate/free DMA port and buffer
1375  */
1376 
1377 static void __devinit wbsd_request_dma(struct wbsd_host *host, int dma)
1378 {
1379 	if (dma < 0)
1380 		return;
1381 
1382 	if (request_dma(dma, DRIVER_NAME))
1383 		goto err;
1384 
1385 	/*
1386 	 * We need to allocate a special buffer in
1387 	 * order for ISA to be able to DMA to it.
1388 	 */
1389 	host->dma_buffer = kmalloc(WBSD_DMA_SIZE,
1390 		GFP_NOIO | GFP_DMA | __GFP_REPEAT | __GFP_NOWARN);
1391 	if (!host->dma_buffer)
1392 		goto free;
1393 
1394 	/*
1395 	 * Translate the address to a physical address.
1396 	 */
1397 	host->dma_addr = dma_map_single(mmc_dev(host->mmc), host->dma_buffer,
1398 		WBSD_DMA_SIZE, DMA_BIDIRECTIONAL);
1399 
1400 	/*
1401 	 * ISA DMA must be aligned on a 64k basis.
1402 	 */
1403 	if ((host->dma_addr & 0xffff) != 0)
1404 		goto kfree;
1405 	/*
1406 	 * ISA cannot access memory above 16 MB.
1407 	 */
1408 	else if (host->dma_addr >= 0x1000000)
1409 		goto kfree;
1410 
1411 	host->dma = dma;
1412 
1413 	return;
1414 
1415 kfree:
1416 	/*
1417 	 * If we've gotten here then there is some kind of alignment bug
1418 	 */
1419 	BUG_ON(1);
1420 
1421 	dma_unmap_single(mmc_dev(host->mmc), host->dma_addr,
1422 		WBSD_DMA_SIZE, DMA_BIDIRECTIONAL);
1423 	host->dma_addr = 0;
1424 
1425 	kfree(host->dma_buffer);
1426 	host->dma_buffer = NULL;
1427 
1428 free:
1429 	free_dma(dma);
1430 
1431 err:
1432 	pr_warning(DRIVER_NAME ": Unable to allocate DMA %d. "
1433 		"Falling back on FIFO.\n", dma);
1434 }
1435 
1436 static void wbsd_release_dma(struct wbsd_host *host)
1437 {
1438 	if (host->dma_addr) {
1439 		dma_unmap_single(mmc_dev(host->mmc), host->dma_addr,
1440 			WBSD_DMA_SIZE, DMA_BIDIRECTIONAL);
1441 	}
1442 	kfree(host->dma_buffer);
1443 	if (host->dma >= 0)
1444 		free_dma(host->dma);
1445 
1446 	host->dma = -1;
1447 	host->dma_buffer = NULL;
1448 	host->dma_addr = 0;
1449 }
1450 
1451 /*
1452  * Allocate/free IRQ.
1453  */
1454 
1455 static int __devinit wbsd_request_irq(struct wbsd_host *host, int irq)
1456 {
1457 	int ret;
1458 
1459 	/*
1460 	 * Set up tasklets. Must be done before requesting interrupt.
1461 	 */
1462 	tasklet_init(&host->card_tasklet, wbsd_tasklet_card,
1463 			(unsigned long)host);
1464 	tasklet_init(&host->fifo_tasklet, wbsd_tasklet_fifo,
1465 			(unsigned long)host);
1466 	tasklet_init(&host->crc_tasklet, wbsd_tasklet_crc,
1467 			(unsigned long)host);
1468 	tasklet_init(&host->timeout_tasklet, wbsd_tasklet_timeout,
1469 			(unsigned long)host);
1470 	tasklet_init(&host->finish_tasklet, wbsd_tasklet_finish,
1471 			(unsigned long)host);
1472 
1473 	/*
1474 	 * Allocate interrupt.
1475 	 */
1476 	ret = request_irq(irq, wbsd_irq, IRQF_SHARED, DRIVER_NAME, host);
1477 	if (ret)
1478 		return ret;
1479 
1480 	host->irq = irq;
1481 
1482 	return 0;
1483 }
1484 
1485 static void  wbsd_release_irq(struct wbsd_host *host)
1486 {
1487 	if (!host->irq)
1488 		return;
1489 
1490 	free_irq(host->irq, host);
1491 
1492 	host->irq = 0;
1493 
1494 	tasklet_kill(&host->card_tasklet);
1495 	tasklet_kill(&host->fifo_tasklet);
1496 	tasklet_kill(&host->crc_tasklet);
1497 	tasklet_kill(&host->timeout_tasklet);
1498 	tasklet_kill(&host->finish_tasklet);
1499 }
1500 
1501 /*
1502  * Allocate all resources for the host.
1503  */
1504 
1505 static int __devinit wbsd_request_resources(struct wbsd_host *host,
1506 	int base, int irq, int dma)
1507 {
1508 	int ret;
1509 
1510 	/*
1511 	 * Allocate I/O ports.
1512 	 */
1513 	ret = wbsd_request_region(host, base);
1514 	if (ret)
1515 		return ret;
1516 
1517 	/*
1518 	 * Allocate interrupt.
1519 	 */
1520 	ret = wbsd_request_irq(host, irq);
1521 	if (ret)
1522 		return ret;
1523 
1524 	/*
1525 	 * Allocate DMA.
1526 	 */
1527 	wbsd_request_dma(host, dma);
1528 
1529 	return 0;
1530 }
1531 
1532 /*
1533  * Release all resources for the host.
1534  */
1535 
1536 static void wbsd_release_resources(struct wbsd_host *host)
1537 {
1538 	wbsd_release_dma(host);
1539 	wbsd_release_irq(host);
1540 	wbsd_release_regions(host);
1541 }
1542 
1543 /*
1544  * Configure the resources the chip should use.
1545  */
1546 
1547 static void wbsd_chip_config(struct wbsd_host *host)
1548 {
1549 	wbsd_unlock_config(host);
1550 
1551 	/*
1552 	 * Reset the chip.
1553 	 */
1554 	wbsd_write_config(host, WBSD_CONF_SWRST, 1);
1555 	wbsd_write_config(host, WBSD_CONF_SWRST, 0);
1556 
1557 	/*
1558 	 * Select SD/MMC function.
1559 	 */
1560 	wbsd_write_config(host, WBSD_CONF_DEVICE, DEVICE_SD);
1561 
1562 	/*
1563 	 * Set up card detection.
1564 	 */
1565 	wbsd_write_config(host, WBSD_CONF_PINS, WBSD_PINS_DETECT_GP11);
1566 
1567 	/*
1568 	 * Configure chip
1569 	 */
1570 	wbsd_write_config(host, WBSD_CONF_PORT_HI, host->base >> 8);
1571 	wbsd_write_config(host, WBSD_CONF_PORT_LO, host->base & 0xff);
1572 
1573 	wbsd_write_config(host, WBSD_CONF_IRQ, host->irq);
1574 
1575 	if (host->dma >= 0)
1576 		wbsd_write_config(host, WBSD_CONF_DRQ, host->dma);
1577 
1578 	/*
1579 	 * Enable and power up chip.
1580 	 */
1581 	wbsd_write_config(host, WBSD_CONF_ENABLE, 1);
1582 	wbsd_write_config(host, WBSD_CONF_POWER, 0x20);
1583 
1584 	wbsd_lock_config(host);
1585 }
1586 
1587 /*
1588  * Check that configured resources are correct.
1589  */
1590 
1591 static int wbsd_chip_validate(struct wbsd_host *host)
1592 {
1593 	int base, irq, dma;
1594 
1595 	wbsd_unlock_config(host);
1596 
1597 	/*
1598 	 * Select SD/MMC function.
1599 	 */
1600 	wbsd_write_config(host, WBSD_CONF_DEVICE, DEVICE_SD);
1601 
1602 	/*
1603 	 * Read configuration.
1604 	 */
1605 	base = wbsd_read_config(host, WBSD_CONF_PORT_HI) << 8;
1606 	base |= wbsd_read_config(host, WBSD_CONF_PORT_LO);
1607 
1608 	irq = wbsd_read_config(host, WBSD_CONF_IRQ);
1609 
1610 	dma = wbsd_read_config(host, WBSD_CONF_DRQ);
1611 
1612 	wbsd_lock_config(host);
1613 
1614 	/*
1615 	 * Validate against given configuration.
1616 	 */
1617 	if (base != host->base)
1618 		return 0;
1619 	if (irq != host->irq)
1620 		return 0;
1621 	if ((dma != host->dma) && (host->dma != -1))
1622 		return 0;
1623 
1624 	return 1;
1625 }
1626 
1627 /*
1628  * Powers down the SD function
1629  */
1630 
1631 static void wbsd_chip_poweroff(struct wbsd_host *host)
1632 {
1633 	wbsd_unlock_config(host);
1634 
1635 	wbsd_write_config(host, WBSD_CONF_DEVICE, DEVICE_SD);
1636 	wbsd_write_config(host, WBSD_CONF_ENABLE, 0);
1637 
1638 	wbsd_lock_config(host);
1639 }
1640 
1641 /*****************************************************************************\
1642  *                                                                           *
1643  * Devices setup and shutdown                                                *
1644  *                                                                           *
1645 \*****************************************************************************/
1646 
1647 static int __devinit wbsd_init(struct device *dev, int base, int irq, int dma,
1648 	int pnp)
1649 {
1650 	struct wbsd_host *host = NULL;
1651 	struct mmc_host *mmc = NULL;
1652 	int ret;
1653 
1654 	ret = wbsd_alloc_mmc(dev);
1655 	if (ret)
1656 		return ret;
1657 
1658 	mmc = dev_get_drvdata(dev);
1659 	host = mmc_priv(mmc);
1660 
1661 	/*
1662 	 * Scan for hardware.
1663 	 */
1664 	ret = wbsd_scan(host);
1665 	if (ret) {
1666 		if (pnp && (ret == -ENODEV)) {
1667 			pr_warning(DRIVER_NAME
1668 				": Unable to confirm device presence. You may "
1669 				"experience lock-ups.\n");
1670 		} else {
1671 			wbsd_free_mmc(dev);
1672 			return ret;
1673 		}
1674 	}
1675 
1676 	/*
1677 	 * Request resources.
1678 	 */
1679 	ret = wbsd_request_resources(host, base, irq, dma);
1680 	if (ret) {
1681 		wbsd_release_resources(host);
1682 		wbsd_free_mmc(dev);
1683 		return ret;
1684 	}
1685 
1686 	/*
1687 	 * See if chip needs to be configured.
1688 	 */
1689 	if (pnp) {
1690 		if ((host->config != 0) && !wbsd_chip_validate(host)) {
1691 			pr_warning(DRIVER_NAME
1692 				": PnP active but chip not configured! "
1693 				"You probably have a buggy BIOS. "
1694 				"Configuring chip manually.\n");
1695 			wbsd_chip_config(host);
1696 		}
1697 	} else
1698 		wbsd_chip_config(host);
1699 
1700 	/*
1701 	 * Power Management stuff. No idea how this works.
1702 	 * Not tested.
1703 	 */
1704 #ifdef CONFIG_PM
1705 	if (host->config) {
1706 		wbsd_unlock_config(host);
1707 		wbsd_write_config(host, WBSD_CONF_PME, 0xA0);
1708 		wbsd_lock_config(host);
1709 	}
1710 #endif
1711 	/*
1712 	 * Allow device to initialise itself properly.
1713 	 */
1714 	mdelay(5);
1715 
1716 	/*
1717 	 * Reset the chip into a known state.
1718 	 */
1719 	wbsd_init_device(host);
1720 
1721 	mmc_add_host(mmc);
1722 
1723 	pr_info("%s: W83L51xD", mmc_hostname(mmc));
1724 	if (host->chip_id != 0)
1725 		printk(" id %x", (int)host->chip_id);
1726 	printk(" at 0x%x irq %d", (int)host->base, (int)host->irq);
1727 	if (host->dma >= 0)
1728 		printk(" dma %d", (int)host->dma);
1729 	else
1730 		printk(" FIFO");
1731 	if (pnp)
1732 		printk(" PnP");
1733 	printk("\n");
1734 
1735 	return 0;
1736 }
1737 
1738 static void __devexit wbsd_shutdown(struct device *dev, int pnp)
1739 {
1740 	struct mmc_host *mmc = dev_get_drvdata(dev);
1741 	struct wbsd_host *host;
1742 
1743 	if (!mmc)
1744 		return;
1745 
1746 	host = mmc_priv(mmc);
1747 
1748 	mmc_remove_host(mmc);
1749 
1750 	/*
1751 	 * Power down the SD/MMC function.
1752 	 */
1753 	if (!pnp)
1754 		wbsd_chip_poweroff(host);
1755 
1756 	wbsd_release_resources(host);
1757 
1758 	wbsd_free_mmc(dev);
1759 }
1760 
1761 /*
1762  * Non-PnP
1763  */
1764 
1765 static int __devinit wbsd_probe(struct platform_device *dev)
1766 {
1767 	/* Use the module parameters for resources */
1768 	return wbsd_init(&dev->dev, param_io, param_irq, param_dma, 0);
1769 }
1770 
1771 static int __devexit wbsd_remove(struct platform_device *dev)
1772 {
1773 	wbsd_shutdown(&dev->dev, 0);
1774 
1775 	return 0;
1776 }
1777 
1778 /*
1779  * PnP
1780  */
1781 
1782 #ifdef CONFIG_PNP
1783 
1784 static int __devinit
1785 wbsd_pnp_probe(struct pnp_dev *pnpdev, const struct pnp_device_id *dev_id)
1786 {
1787 	int io, irq, dma;
1788 
1789 	/*
1790 	 * Get resources from PnP layer.
1791 	 */
1792 	io = pnp_port_start(pnpdev, 0);
1793 	irq = pnp_irq(pnpdev, 0);
1794 	if (pnp_dma_valid(pnpdev, 0))
1795 		dma = pnp_dma(pnpdev, 0);
1796 	else
1797 		dma = -1;
1798 
1799 	DBGF("PnP resources: port %3x irq %d dma %d\n", io, irq, dma);
1800 
1801 	return wbsd_init(&pnpdev->dev, io, irq, dma, 1);
1802 }
1803 
1804 static void __devexit wbsd_pnp_remove(struct pnp_dev *dev)
1805 {
1806 	wbsd_shutdown(&dev->dev, 1);
1807 }
1808 
1809 #endif /* CONFIG_PNP */
1810 
1811 /*
1812  * Power management
1813  */
1814 
1815 #ifdef CONFIG_PM
1816 
1817 static int wbsd_suspend(struct wbsd_host *host, pm_message_t state)
1818 {
1819 	BUG_ON(host == NULL);
1820 
1821 	return mmc_suspend_host(host->mmc);
1822 }
1823 
1824 static int wbsd_resume(struct wbsd_host *host)
1825 {
1826 	BUG_ON(host == NULL);
1827 
1828 	wbsd_init_device(host);
1829 
1830 	return mmc_resume_host(host->mmc);
1831 }
1832 
1833 static int wbsd_platform_suspend(struct platform_device *dev,
1834 				 pm_message_t state)
1835 {
1836 	struct mmc_host *mmc = platform_get_drvdata(dev);
1837 	struct wbsd_host *host;
1838 	int ret;
1839 
1840 	if (mmc == NULL)
1841 		return 0;
1842 
1843 	DBGF("Suspending...\n");
1844 
1845 	host = mmc_priv(mmc);
1846 
1847 	ret = wbsd_suspend(host, state);
1848 	if (ret)
1849 		return ret;
1850 
1851 	wbsd_chip_poweroff(host);
1852 
1853 	return 0;
1854 }
1855 
1856 static int wbsd_platform_resume(struct platform_device *dev)
1857 {
1858 	struct mmc_host *mmc = platform_get_drvdata(dev);
1859 	struct wbsd_host *host;
1860 
1861 	if (mmc == NULL)
1862 		return 0;
1863 
1864 	DBGF("Resuming...\n");
1865 
1866 	host = mmc_priv(mmc);
1867 
1868 	wbsd_chip_config(host);
1869 
1870 	/*
1871 	 * Allow device to initialise itself properly.
1872 	 */
1873 	mdelay(5);
1874 
1875 	return wbsd_resume(host);
1876 }
1877 
1878 #ifdef CONFIG_PNP
1879 
1880 static int wbsd_pnp_suspend(struct pnp_dev *pnp_dev, pm_message_t state)
1881 {
1882 	struct mmc_host *mmc = dev_get_drvdata(&pnp_dev->dev);
1883 	struct wbsd_host *host;
1884 
1885 	if (mmc == NULL)
1886 		return 0;
1887 
1888 	DBGF("Suspending...\n");
1889 
1890 	host = mmc_priv(mmc);
1891 
1892 	return wbsd_suspend(host, state);
1893 }
1894 
1895 static int wbsd_pnp_resume(struct pnp_dev *pnp_dev)
1896 {
1897 	struct mmc_host *mmc = dev_get_drvdata(&pnp_dev->dev);
1898 	struct wbsd_host *host;
1899 
1900 	if (mmc == NULL)
1901 		return 0;
1902 
1903 	DBGF("Resuming...\n");
1904 
1905 	host = mmc_priv(mmc);
1906 
1907 	/*
1908 	 * See if chip needs to be configured.
1909 	 */
1910 	if (host->config != 0) {
1911 		if (!wbsd_chip_validate(host)) {
1912 			pr_warning(DRIVER_NAME
1913 				": PnP active but chip not configured! "
1914 				"You probably have a buggy BIOS. "
1915 				"Configuring chip manually.\n");
1916 			wbsd_chip_config(host);
1917 		}
1918 	}
1919 
1920 	/*
1921 	 * Allow device to initialise itself properly.
1922 	 */
1923 	mdelay(5);
1924 
1925 	return wbsd_resume(host);
1926 }
1927 
1928 #endif /* CONFIG_PNP */
1929 
1930 #else /* CONFIG_PM */
1931 
1932 #define wbsd_platform_suspend NULL
1933 #define wbsd_platform_resume NULL
1934 
1935 #define wbsd_pnp_suspend NULL
1936 #define wbsd_pnp_resume NULL
1937 
1938 #endif /* CONFIG_PM */
1939 
1940 static struct platform_device *wbsd_device;
1941 
1942 static struct platform_driver wbsd_driver = {
1943 	.probe		= wbsd_probe,
1944 	.remove		= __devexit_p(wbsd_remove),
1945 
1946 	.suspend	= wbsd_platform_suspend,
1947 	.resume		= wbsd_platform_resume,
1948 	.driver		= {
1949 		.name	= DRIVER_NAME,
1950 		.owner	= THIS_MODULE,
1951 	},
1952 };
1953 
1954 #ifdef CONFIG_PNP
1955 
1956 static struct pnp_driver wbsd_pnp_driver = {
1957 	.name		= DRIVER_NAME,
1958 	.id_table	= pnp_dev_table,
1959 	.probe		= wbsd_pnp_probe,
1960 	.remove		= __devexit_p(wbsd_pnp_remove),
1961 
1962 	.suspend	= wbsd_pnp_suspend,
1963 	.resume		= wbsd_pnp_resume,
1964 };
1965 
1966 #endif /* CONFIG_PNP */
1967 
1968 /*
1969  * Module loading/unloading
1970  */
1971 
1972 static int __init wbsd_drv_init(void)
1973 {
1974 	int result;
1975 
1976 	pr_info(DRIVER_NAME
1977 		": Winbond W83L51xD SD/MMC card interface driver\n");
1978 	pr_info(DRIVER_NAME ": Copyright(c) Pierre Ossman\n");
1979 
1980 #ifdef CONFIG_PNP
1981 
1982 	if (!param_nopnp) {
1983 		result = pnp_register_driver(&wbsd_pnp_driver);
1984 		if (result < 0)
1985 			return result;
1986 	}
1987 #endif /* CONFIG_PNP */
1988 
1989 	if (param_nopnp) {
1990 		result = platform_driver_register(&wbsd_driver);
1991 		if (result < 0)
1992 			return result;
1993 
1994 		wbsd_device = platform_device_alloc(DRIVER_NAME, -1);
1995 		if (!wbsd_device) {
1996 			platform_driver_unregister(&wbsd_driver);
1997 			return -ENOMEM;
1998 		}
1999 
2000 		result = platform_device_add(wbsd_device);
2001 		if (result) {
2002 			platform_device_put(wbsd_device);
2003 			platform_driver_unregister(&wbsd_driver);
2004 			return result;
2005 		}
2006 	}
2007 
2008 	return 0;
2009 }
2010 
2011 static void __exit wbsd_drv_exit(void)
2012 {
2013 #ifdef CONFIG_PNP
2014 
2015 	if (!param_nopnp)
2016 		pnp_unregister_driver(&wbsd_pnp_driver);
2017 
2018 #endif /* CONFIG_PNP */
2019 
2020 	if (param_nopnp) {
2021 		platform_device_unregister(wbsd_device);
2022 
2023 		platform_driver_unregister(&wbsd_driver);
2024 	}
2025 
2026 	DBG("unloaded\n");
2027 }
2028 
2029 module_init(wbsd_drv_init);
2030 module_exit(wbsd_drv_exit);
2031 #ifdef CONFIG_PNP
2032 module_param_named(nopnp, param_nopnp, uint, 0444);
2033 #endif
2034 module_param_named(io, param_io, uint, 0444);
2035 module_param_named(irq, param_irq, uint, 0444);
2036 module_param_named(dma, param_dma, int, 0444);
2037 
2038 MODULE_LICENSE("GPL");
2039 MODULE_AUTHOR("Pierre Ossman <pierre@ossman.eu>");
2040 MODULE_DESCRIPTION("Winbond W83L51xD SD/MMC card interface driver");
2041 
2042 #ifdef CONFIG_PNP
2043 MODULE_PARM_DESC(nopnp, "Scan for device instead of relying on PNP. (default 0)");
2044 #endif
2045 MODULE_PARM_DESC(io, "I/O base to allocate. Must be 8 byte aligned. (default 0x248)");
2046 MODULE_PARM_DESC(irq, "IRQ to allocate. (default 6)");
2047 MODULE_PARM_DESC(dma, "DMA channel to allocate. -1 for no DMA. (default 2)");
2048