blob: 5b014c370e809dc5ecfd6acd57384f6f6295877c [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Block driver for media (i.e., flash cards)
3 *
4 * Copyright 2002 Hewlett-Packard Company
5 *
6 * Use consistent with the GNU GPL is permitted,
7 * provided that this copyright notice is
8 * preserved in its entirety in all copies and derived works.
9 *
10 * HEWLETT-PACKARD COMPANY MAKES NO WARRANTIES, EXPRESSED OR IMPLIED,
11 * AS TO THE USEFULNESS OR CORRECTNESS OF THIS CODE OR ITS
12 * FITNESS FOR ANY PARTICULAR PURPOSE.
13 *
14 * Many thanks to Alessandro Rubini and Jonathan Corbet!
15 *
16 * Author: Andrew Christian
17 * 28 May 2002
18 */
19#include <linux/moduleparam.h>
20#include <linux/module.h>
21#include <linux/init.h>
22
23#include <linux/sched.h>
24#include <linux/kernel.h>
25#include <linux/fs.h>
26#include <linux/errno.h>
27#include <linux/hdreg.h>
28#include <linux/kdev_t.h>
29#include <linux/blkdev.h>
30#include <linux/devfs_fs_kernel.h>
Arjan van de Vena621aae2006-01-12 18:43:35 +000031#include <linux/mutex.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070032
33#include <linux/mmc/card.h>
34#include <linux/mmc/protocol.h>
35
36#include <asm/system.h>
37#include <asm/uaccess.h>
38
39#include "mmc_queue.h"
40
41/*
42 * max 8 partitions per card
43 */
44#define MMC_SHIFT 3
45
46static int major;
47
48/*
49 * There is one mmc_blk_data per slot.
50 */
51struct mmc_blk_data {
52 spinlock_t lock;
53 struct gendisk *disk;
54 struct mmc_queue queue;
55
56 unsigned int usage;
57 unsigned int block_bits;
Russell Kinga6f6c962006-01-03 22:38:44 +000058 unsigned int read_only;
Linus Torvalds1da177e2005-04-16 15:20:36 -070059};
60
Arjan van de Vena621aae2006-01-12 18:43:35 +000061static DEFINE_MUTEX(open_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070062
63static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk)
64{
65 struct mmc_blk_data *md;
66
Arjan van de Vena621aae2006-01-12 18:43:35 +000067 mutex_lock(&open_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070068 md = disk->private_data;
69 if (md && md->usage == 0)
70 md = NULL;
71 if (md)
72 md->usage++;
Arjan van de Vena621aae2006-01-12 18:43:35 +000073 mutex_unlock(&open_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070074
75 return md;
76}
77
78static void mmc_blk_put(struct mmc_blk_data *md)
79{
Arjan van de Vena621aae2006-01-12 18:43:35 +000080 mutex_lock(&open_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070081 md->usage--;
82 if (md->usage == 0) {
83 put_disk(md->disk);
84 mmc_cleanup_queue(&md->queue);
85 kfree(md);
86 }
Arjan van de Vena621aae2006-01-12 18:43:35 +000087 mutex_unlock(&open_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070088}
89
90static int mmc_blk_open(struct inode *inode, struct file *filp)
91{
92 struct mmc_blk_data *md;
93 int ret = -ENXIO;
94
95 md = mmc_blk_get(inode->i_bdev->bd_disk);
96 if (md) {
97 if (md->usage == 2)
98 check_disk_change(inode->i_bdev);
99 ret = 0;
Pierre Ossmana00fc092005-09-06 15:18:52 -0700100
Russell Kinga6f6c962006-01-03 22:38:44 +0000101 if ((filp->f_mode & FMODE_WRITE) && md->read_only)
Pierre Ossmana00fc092005-09-06 15:18:52 -0700102 ret = -EROFS;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 }
104
105 return ret;
106}
107
108static int mmc_blk_release(struct inode *inode, struct file *filp)
109{
110 struct mmc_blk_data *md = inode->i_bdev->bd_disk->private_data;
111
112 mmc_blk_put(md);
113 return 0;
114}
115
116static int
Christoph Hellwiga885c8c2006-01-08 01:02:50 -0800117mmc_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118{
Christoph Hellwiga885c8c2006-01-08 01:02:50 -0800119 geo->cylinders = get_capacity(bdev->bd_disk) / (4 * 16);
120 geo->heads = 4;
121 geo->sectors = 16;
122 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700123}
124
125static struct block_device_operations mmc_bdops = {
126 .open = mmc_blk_open,
127 .release = mmc_blk_release,
Christoph Hellwiga885c8c2006-01-08 01:02:50 -0800128 .getgeo = mmc_blk_getgeo,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129 .owner = THIS_MODULE,
130};
131
132struct mmc_blk_request {
133 struct mmc_request mrq;
134 struct mmc_command cmd;
135 struct mmc_command stop;
136 struct mmc_data data;
137};
138
139static int mmc_blk_prep_rq(struct mmc_queue *mq, struct request *req)
140{
141 struct mmc_blk_data *md = mq->data;
142 int stat = BLKPREP_OK;
143
144 /*
145 * If we have no device, we haven't finished initialising.
146 */
147 if (!md || !mq->card) {
148 printk(KERN_ERR "%s: killing request - no device/host\n",
149 req->rq_disk->disk_name);
150 stat = BLKPREP_KILL;
151 }
152
153 return stat;
154}
155
156static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
157{
158 struct mmc_blk_data *md = mq->data;
159 struct mmc_card *card = md->queue.card;
160 int ret;
161
162 if (mmc_card_claim_host(card))
163 goto cmd_err;
164
165 do {
166 struct mmc_blk_request brq;
167 struct mmc_command cmd;
168
169 memset(&brq, 0, sizeof(struct mmc_blk_request));
170 brq.mrq.cmd = &brq.cmd;
171 brq.mrq.data = &brq.data;
172
173 brq.cmd.arg = req->sector << 9;
174 brq.cmd.flags = MMC_RSP_R1;
175 brq.data.timeout_ns = card->csd.tacc_ns * 10;
176 brq.data.timeout_clks = card->csd.tacc_clks * 10;
177 brq.data.blksz_bits = md->block_bits;
178 brq.data.blocks = req->nr_sectors >> (md->block_bits - 9);
179 brq.stop.opcode = MMC_STOP_TRANSMISSION;
180 brq.stop.arg = 0;
181 brq.stop.flags = MMC_RSP_R1B;
182
183 if (rq_data_dir(req) == READ) {
184 brq.cmd.opcode = brq.data.blocks > 1 ? MMC_READ_MULTIPLE_BLOCK : MMC_READ_SINGLE_BLOCK;
185 brq.data.flags |= MMC_DATA_READ;
186 } else {
187 brq.cmd.opcode = MMC_WRITE_BLOCK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188 brq.data.flags |= MMC_DATA_WRITE;
189 brq.data.blocks = 1;
190 }
Russell King788ee7b2006-01-09 21:12:17 +0000191
192 if (brq.data.blocks > 1) {
193 brq.data.flags |= MMC_DATA_MULTI;
194 brq.mrq.stop = &brq.stop;
195 } else {
196 brq.mrq.stop = NULL;
197 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198
199 brq.data.sg = mq->sg;
200 brq.data.sg_len = blk_rq_map_sg(req->q, req, brq.data.sg);
201
202 mmc_wait_for_req(card->host, &brq.mrq);
203 if (brq.cmd.error) {
204 printk(KERN_ERR "%s: error %d sending read/write command\n",
205 req->rq_disk->disk_name, brq.cmd.error);
206 goto cmd_err;
207 }
208
209 if (brq.data.error) {
210 printk(KERN_ERR "%s: error %d transferring data\n",
211 req->rq_disk->disk_name, brq.data.error);
212 goto cmd_err;
213 }
214
215 if (brq.stop.error) {
216 printk(KERN_ERR "%s: error %d sending stop command\n",
217 req->rq_disk->disk_name, brq.stop.error);
218 goto cmd_err;
219 }
220
221 do {
222 int err;
223
224 cmd.opcode = MMC_SEND_STATUS;
225 cmd.arg = card->rca << 16;
226 cmd.flags = MMC_RSP_R1;
227 err = mmc_wait_for_cmd(card->host, &cmd, 5);
228 if (err) {
229 printk(KERN_ERR "%s: error %d requesting status\n",
230 req->rq_disk->disk_name, err);
231 goto cmd_err;
232 }
233 } while (!(cmd.resp[0] & R1_READY_FOR_DATA));
234
235#if 0
236 if (cmd.resp[0] & ~0x00000900)
237 printk(KERN_ERR "%s: status = %08x\n",
238 req->rq_disk->disk_name, cmd.resp[0]);
239 if (mmc_decode_status(cmd.resp))
240 goto cmd_err;
241#endif
242
243 /*
244 * A block was successfully transferred.
245 */
246 spin_lock_irq(&md->lock);
247 ret = end_that_request_chunk(req, 1, brq.data.bytes_xfered);
248 if (!ret) {
249 /*
250 * The whole request completed successfully.
251 */
252 add_disk_randomness(req->rq_disk);
253 blkdev_dequeue_request(req);
Tejun Heo8ffdc652006-01-06 09:49:03 +0100254 end_that_request_last(req, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255 }
256 spin_unlock_irq(&md->lock);
257 } while (ret);
258
259 mmc_card_release_host(card);
260
261 return 1;
262
263 cmd_err:
264 mmc_card_release_host(card);
265
266 /*
267 * This is a little draconian, but until we get proper
268 * error handling sorted out here, its the best we can
269 * do - especially as some hosts have no idea how much
270 * data was transferred before the error occurred.
271 */
272 spin_lock_irq(&md->lock);
273 do {
274 ret = end_that_request_chunk(req, 0,
275 req->current_nr_sectors << 9);
276 } while (ret);
277
278 add_disk_randomness(req->rq_disk);
279 blkdev_dequeue_request(req);
Tejun Heo8ffdc652006-01-06 09:49:03 +0100280 end_that_request_last(req, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281 spin_unlock_irq(&md->lock);
282
283 return 0;
284}
285
286#define MMC_NUM_MINORS (256 >> MMC_SHIFT)
287
288static unsigned long dev_use[MMC_NUM_MINORS/(8*sizeof(unsigned long))];
289
Russell Kinga6f6c962006-01-03 22:38:44 +0000290static inline int mmc_blk_readonly(struct mmc_card *card)
291{
292 return mmc_card_readonly(card) ||
293 !(card->csd.cmdclass & CCC_BLOCK_WRITE);
294}
295
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
297{
298 struct mmc_blk_data *md;
299 int devidx, ret;
300
301 devidx = find_first_zero_bit(dev_use, MMC_NUM_MINORS);
302 if (devidx >= MMC_NUM_MINORS)
303 return ERR_PTR(-ENOSPC);
304 __set_bit(devidx, dev_use);
305
306 md = kmalloc(sizeof(struct mmc_blk_data), GFP_KERNEL);
Russell Kinga6f6c962006-01-03 22:38:44 +0000307 if (!md) {
308 ret = -ENOMEM;
309 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310 }
Russell Kinga6f6c962006-01-03 22:38:44 +0000311
312 memset(md, 0, sizeof(struct mmc_blk_data));
313
314 /*
315 * Set the read-only status based on the supported commands
316 * and the write protect switch.
317 */
318 md->read_only = mmc_blk_readonly(card);
319
320 /*
321 * Figure out a workable block size. MMC cards have:
322 * - two block sizes, one for read and one for write.
323 * - may support partial reads and/or writes
324 * (allows block sizes smaller than specified)
325 */
326 md->block_bits = card->csd.read_blkbits;
327 if (card->csd.write_blkbits != card->csd.read_blkbits) {
328 if (card->csd.write_blkbits < card->csd.read_blkbits &&
329 card->csd.read_partial) {
330 /*
331 * write block size is smaller than read block
332 * size, but we support partial reads, so choose
333 * the smaller write block size.
334 */
335 md->block_bits = card->csd.write_blkbits;
336 } else if (card->csd.write_blkbits > card->csd.read_blkbits &&
337 card->csd.write_partial) {
338 /*
339 * read block size is smaller than write block
340 * size, but we support partial writes. Use read
341 * block size.
342 */
343 } else {
344 /*
345 * We don't support this configuration for writes.
346 */
347 printk(KERN_ERR "%s: unable to select block size for "
348 "writing (rb%u wb%u rp%u wp%u)\n",
349 md->disk->disk_name,
350 1 << card->csd.read_blkbits,
351 1 << card->csd.write_blkbits,
352 card->csd.read_partial,
353 card->csd.write_partial);
354 md->read_only = 1;
355 }
356 }
357
358 /*
359 * Refuse to allow block sizes smaller than 512 bytes.
360 */
361 if (md->block_bits < 9) {
362 printk(KERN_ERR "%s: unable to support block size %u\n",
363 mmc_card_id(card), 1 << md->block_bits);
364 ret = -EINVAL;
365 goto err_kfree;
366 }
367
368 md->disk = alloc_disk(1 << MMC_SHIFT);
369 if (md->disk == NULL) {
370 ret = -ENOMEM;
371 goto err_kfree;
372 }
373
374 spin_lock_init(&md->lock);
375 md->usage = 1;
376
377 ret = mmc_init_queue(&md->queue, card, &md->lock);
378 if (ret)
379 goto err_putdisk;
380
381 md->queue.prep_fn = mmc_blk_prep_rq;
382 md->queue.issue_fn = mmc_blk_issue_rq;
383 md->queue.data = md;
384
385 md->disk->major = major;
386 md->disk->first_minor = devidx << MMC_SHIFT;
387 md->disk->fops = &mmc_bdops;
388 md->disk->private_data = md;
389 md->disk->queue = md->queue.queue;
390 md->disk->driverfs_dev = &card->dev;
391
392 /*
393 * As discussed on lkml, GENHD_FL_REMOVABLE should:
394 *
395 * - be set for removable media with permanent block devices
396 * - be unset for removable block devices with permanent media
397 *
398 * Since MMC block devices clearly fall under the second
399 * case, we do not set GENHD_FL_REMOVABLE. Userspace
400 * should use the block device creation/destruction hotplug
401 * messages to tell when the card is present.
402 */
403
404 sprintf(md->disk->disk_name, "mmcblk%d", devidx);
405 sprintf(md->disk->devfs_name, "mmc/blk%d", devidx);
406
407 blk_queue_hardsect_size(md->queue.queue, 1 << md->block_bits);
408
409 /*
410 * The CSD capacity field is in units of read_blkbits.
411 * set_capacity takes units of 512 bytes.
412 */
413 set_capacity(md->disk, card->csd.capacity << (card->csd.read_blkbits - 9));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700414 return md;
Russell Kinga6f6c962006-01-03 22:38:44 +0000415
416 err_putdisk:
417 put_disk(md->disk);
418 err_kfree:
419 kfree(md);
420 out:
421 return ERR_PTR(ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700422}
423
424static int
425mmc_blk_set_blksize(struct mmc_blk_data *md, struct mmc_card *card)
426{
427 struct mmc_command cmd;
428 int err;
429
430 mmc_card_claim_host(card);
431 cmd.opcode = MMC_SET_BLOCKLEN;
Russell Kingd2b18392005-12-22 23:21:38 +0000432 cmd.arg = 1 << md->block_bits;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433 cmd.flags = MMC_RSP_R1;
434 err = mmc_wait_for_cmd(card->host, &cmd, 5);
435 mmc_card_release_host(card);
436
437 if (err) {
438 printk(KERN_ERR "%s: unable to set block size to %d: %d\n",
439 md->disk->disk_name, cmd.arg, err);
440 return -EINVAL;
441 }
442
443 return 0;
444}
445
446static int mmc_blk_probe(struct mmc_card *card)
447{
448 struct mmc_blk_data *md;
449 int err;
450
Pierre Ossman912490d2005-05-21 10:27:02 +0100451 /*
452 * Check that the card supports the command class(es) we need.
453 */
454 if (!(card->csd.cmdclass & CCC_BLOCK_READ))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455 return -ENODEV;
456
Linus Torvalds1da177e2005-04-16 15:20:36 -0700457 md = mmc_blk_alloc(card);
458 if (IS_ERR(md))
459 return PTR_ERR(md);
460
461 err = mmc_blk_set_blksize(md, card);
462 if (err)
463 goto out;
464
Andrew Morton51828ab2006-01-13 21:44:18 +0000465 printk(KERN_INFO "%s: %s %s %lluKiB %s\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466 md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
Andrew Morton51828ab2006-01-13 21:44:18 +0000467 (unsigned long long)(get_capacity(md->disk) >> 1),
468 md->read_only ? "(ro)" : "");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469
470 mmc_set_drvdata(card, md);
471 add_disk(md->disk);
472 return 0;
473
474 out:
475 mmc_blk_put(md);
476
477 return err;
478}
479
480static void mmc_blk_remove(struct mmc_card *card)
481{
482 struct mmc_blk_data *md = mmc_get_drvdata(card);
483
484 if (md) {
485 int devidx;
486
487 del_gendisk(md->disk);
488
489 /*
490 * I think this is needed.
491 */
492 md->disk->queue = NULL;
493
494 devidx = md->disk->first_minor >> MMC_SHIFT;
495 __clear_bit(devidx, dev_use);
496
497 mmc_blk_put(md);
498 }
499 mmc_set_drvdata(card, NULL);
500}
501
502#ifdef CONFIG_PM
503static int mmc_blk_suspend(struct mmc_card *card, pm_message_t state)
504{
505 struct mmc_blk_data *md = mmc_get_drvdata(card);
506
507 if (md) {
508 mmc_queue_suspend(&md->queue);
509 }
510 return 0;
511}
512
513static int mmc_blk_resume(struct mmc_card *card)
514{
515 struct mmc_blk_data *md = mmc_get_drvdata(card);
516
517 if (md) {
518 mmc_blk_set_blksize(md, card);
519 mmc_queue_resume(&md->queue);
520 }
521 return 0;
522}
523#else
524#define mmc_blk_suspend NULL
525#define mmc_blk_resume NULL
526#endif
527
528static struct mmc_driver mmc_driver = {
529 .drv = {
530 .name = "mmcblk",
531 },
532 .probe = mmc_blk_probe,
533 .remove = mmc_blk_remove,
534 .suspend = mmc_blk_suspend,
535 .resume = mmc_blk_resume,
536};
537
538static int __init mmc_blk_init(void)
539{
540 int res = -ENOMEM;
541
542 res = register_blkdev(major, "mmc");
543 if (res < 0) {
544 printk(KERN_WARNING "Unable to get major %d for MMC media: %d\n",
545 major, res);
546 goto out;
547 }
548 if (major == 0)
549 major = res;
550
551 devfs_mk_dir("mmc");
552 return mmc_register_driver(&mmc_driver);
553
554 out:
555 return res;
556}
557
558static void __exit mmc_blk_exit(void)
559{
560 mmc_unregister_driver(&mmc_driver);
561 devfs_remove("mmc");
562 unregister_blkdev(major, "mmc");
563}
564
565module_init(mmc_blk_init);
566module_exit(mmc_blk_exit);
567
568MODULE_LICENSE("GPL");
569MODULE_DESCRIPTION("Multimedia Card (MMC) block device driver");
570
571module_param(major, int, 0444);
572MODULE_PARM_DESC(major, "specify the major device number for MMC block driver");