2 * Block driver for media (i.e., flash cards)
4 * Copyright 2002 Hewlett-Packard Company
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.
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.
14 * Many thanks to Alessandro Rubini and Jonathan Corbet!
16 * Author: Andrew Christian
19 #include <linux/moduleparam.h>
20 #include <linux/module.h>
21 #include <linux/init.h>
23 #include <linux/sched.h>
24 #include <linux/kernel.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/mutex.h>
32 #include <linux/mmc/card.h>
33 #include <linux/mmc/host.h>
34 #include <linux/mmc/protocol.h>
35 #include <linux/mmc/host.h>
37 #include <asm/system.h>
38 #include <asm/uaccess.h>
40 #include "mmc_queue.h"
43 * max 8 partitions per card
50 * There is one mmc_blk_data per slot.
55 struct mmc_queue queue
;
58 unsigned int block_bits
;
59 unsigned int read_only
;
62 static DEFINE_MUTEX(open_lock
);
64 static struct mmc_blk_data
*mmc_blk_get(struct gendisk
*disk
)
66 struct mmc_blk_data
*md
;
68 mutex_lock(&open_lock
);
69 md
= disk
->private_data
;
70 if (md
&& md
->usage
== 0)
74 mutex_unlock(&open_lock
);
79 static void mmc_blk_put(struct mmc_blk_data
*md
)
81 mutex_lock(&open_lock
);
85 mmc_cleanup_queue(&md
->queue
);
88 mutex_unlock(&open_lock
);
91 static int mmc_blk_open(struct inode
*inode
, struct file
*filp
)
93 struct mmc_blk_data
*md
;
96 md
= mmc_blk_get(inode
->i_bdev
->bd_disk
);
99 check_disk_change(inode
->i_bdev
);
102 if ((filp
->f_mode
& FMODE_WRITE
) && md
->read_only
)
109 static int mmc_blk_release(struct inode
*inode
, struct file
*filp
)
111 struct mmc_blk_data
*md
= inode
->i_bdev
->bd_disk
->private_data
;
118 mmc_blk_getgeo(struct block_device
*bdev
, struct hd_geometry
*geo
)
120 geo
->cylinders
= get_capacity(bdev
->bd_disk
) / (4 * 16);
126 static struct block_device_operations mmc_bdops
= {
127 .open
= mmc_blk_open
,
128 .release
= mmc_blk_release
,
129 .getgeo
= mmc_blk_getgeo
,
130 .owner
= THIS_MODULE
,
133 struct mmc_blk_request
{
134 struct mmc_request mrq
;
135 struct mmc_command cmd
;
136 struct mmc_command stop
;
137 struct mmc_data data
;
140 static int mmc_blk_prep_rq(struct mmc_queue
*mq
, struct request
*req
)
142 struct mmc_blk_data
*md
= mq
->data
;
143 int stat
= BLKPREP_OK
;
146 * If we have no device, we haven't finished initialising.
148 if (!md
|| !mq
->card
) {
149 printk(KERN_ERR
"%s: killing request - no device/host\n",
150 req
->rq_disk
->disk_name
);
157 static int mmc_blk_issue_rq(struct mmc_queue
*mq
, struct request
*req
)
159 struct mmc_blk_data
*md
= mq
->data
;
160 struct mmc_card
*card
= md
->queue
.card
;
163 if (mmc_card_claim_host(card
))
167 struct mmc_blk_request brq
;
168 struct mmc_command cmd
;
169 u32 readcmd
, writecmd
;
171 memset(&brq
, 0, sizeof(struct mmc_blk_request
));
172 brq
.mrq
.cmd
= &brq
.cmd
;
173 brq
.mrq
.data
= &brq
.data
;
175 brq
.cmd
.arg
= req
->sector
<< 9;
176 brq
.cmd
.flags
= MMC_RSP_R1
| MMC_CMD_ADTC
;
177 brq
.data
.blksz
= 1 << md
->block_bits
;
178 brq
.data
.blocks
= req
->nr_sectors
>> (md
->block_bits
- 9);
179 brq
.stop
.opcode
= MMC_STOP_TRANSMISSION
;
181 brq
.stop
.flags
= MMC_RSP_R1B
| MMC_CMD_AC
;
183 mmc_set_data_timeout(&brq
.data
, card
, rq_data_dir(req
) != READ
);
186 * If the host doesn't support multiple block writes, force
187 * block writes to single block.
189 if (rq_data_dir(req
) != READ
&&
190 !(card
->host
->caps
& MMC_CAP_MULTIWRITE
))
193 if (brq
.data
.blocks
> 1) {
194 brq
.data
.flags
|= MMC_DATA_MULTI
;
195 brq
.mrq
.stop
= &brq
.stop
;
196 readcmd
= MMC_READ_MULTIPLE_BLOCK
;
197 writecmd
= MMC_WRITE_MULTIPLE_BLOCK
;
200 readcmd
= MMC_READ_SINGLE_BLOCK
;
201 writecmd
= MMC_WRITE_BLOCK
;
204 if (rq_data_dir(req
) == READ
) {
205 brq
.cmd
.opcode
= readcmd
;
206 brq
.data
.flags
|= MMC_DATA_READ
;
208 brq
.cmd
.opcode
= writecmd
;
209 brq
.data
.flags
|= MMC_DATA_WRITE
;
212 brq
.data
.sg
= mq
->sg
;
213 brq
.data
.sg_len
= blk_rq_map_sg(req
->q
, req
, brq
.data
.sg
);
215 mmc_wait_for_req(card
->host
, &brq
.mrq
);
217 printk(KERN_ERR
"%s: error %d sending read/write command\n",
218 req
->rq_disk
->disk_name
, brq
.cmd
.error
);
222 if (brq
.data
.error
) {
223 printk(KERN_ERR
"%s: error %d transferring data\n",
224 req
->rq_disk
->disk_name
, brq
.data
.error
);
228 if (brq
.stop
.error
) {
229 printk(KERN_ERR
"%s: error %d sending stop command\n",
230 req
->rq_disk
->disk_name
, brq
.stop
.error
);
234 if (rq_data_dir(req
) != READ
) {
238 cmd
.opcode
= MMC_SEND_STATUS
;
239 cmd
.arg
= card
->rca
<< 16;
240 cmd
.flags
= MMC_RSP_R1
| MMC_CMD_AC
;
241 err
= mmc_wait_for_cmd(card
->host
, &cmd
, 5);
243 printk(KERN_ERR
"%s: error %d requesting status\n",
244 req
->rq_disk
->disk_name
, err
);
247 } while (!(cmd
.resp
[0] & R1_READY_FOR_DATA
));
250 if (cmd
.resp
[0] & ~0x00000900)
251 printk(KERN_ERR
"%s: status = %08x\n",
252 req
->rq_disk
->disk_name
, cmd
.resp
[0]);
253 if (mmc_decode_status(cmd
.resp
))
259 * A block was successfully transferred.
261 spin_lock_irq(&md
->lock
);
262 ret
= end_that_request_chunk(req
, 1, brq
.data
.bytes_xfered
);
265 * The whole request completed successfully.
267 add_disk_randomness(req
->rq_disk
);
268 blkdev_dequeue_request(req
);
269 end_that_request_last(req
, 1);
271 spin_unlock_irq(&md
->lock
);
274 mmc_card_release_host(card
);
279 mmc_card_release_host(card
);
282 * This is a little draconian, but until we get proper
283 * error handling sorted out here, its the best we can
284 * do - especially as some hosts have no idea how much
285 * data was transferred before the error occurred.
287 spin_lock_irq(&md
->lock
);
289 ret
= end_that_request_chunk(req
, 0,
290 req
->current_nr_sectors
<< 9);
293 add_disk_randomness(req
->rq_disk
);
294 blkdev_dequeue_request(req
);
295 end_that_request_last(req
, 0);
296 spin_unlock_irq(&md
->lock
);
301 #define MMC_NUM_MINORS (256 >> MMC_SHIFT)
303 static unsigned long dev_use
[MMC_NUM_MINORS
/(8*sizeof(unsigned long))];
305 static inline int mmc_blk_readonly(struct mmc_card
*card
)
307 return mmc_card_readonly(card
) ||
308 !(card
->csd
.cmdclass
& CCC_BLOCK_WRITE
);
311 static struct mmc_blk_data
*mmc_blk_alloc(struct mmc_card
*card
)
313 struct mmc_blk_data
*md
;
316 devidx
= find_first_zero_bit(dev_use
, MMC_NUM_MINORS
);
317 if (devidx
>= MMC_NUM_MINORS
)
318 return ERR_PTR(-ENOSPC
);
319 __set_bit(devidx
, dev_use
);
321 md
= kmalloc(sizeof(struct mmc_blk_data
), GFP_KERNEL
);
327 memset(md
, 0, sizeof(struct mmc_blk_data
));
330 * Set the read-only status based on the supported commands
331 * and the write protect switch.
333 md
->read_only
= mmc_blk_readonly(card
);
336 * Both SD and MMC specifications state (although a bit
337 * unclearly in the MMC case) that a block size of 512
338 * bytes must always be supported by the card.
342 md
->disk
= alloc_disk(1 << MMC_SHIFT
);
343 if (md
->disk
== NULL
) {
348 spin_lock_init(&md
->lock
);
351 ret
= mmc_init_queue(&md
->queue
, card
, &md
->lock
);
355 md
->queue
.prep_fn
= mmc_blk_prep_rq
;
356 md
->queue
.issue_fn
= mmc_blk_issue_rq
;
359 md
->disk
->major
= major
;
360 md
->disk
->first_minor
= devidx
<< MMC_SHIFT
;
361 md
->disk
->fops
= &mmc_bdops
;
362 md
->disk
->private_data
= md
;
363 md
->disk
->queue
= md
->queue
.queue
;
364 md
->disk
->driverfs_dev
= &card
->dev
;
367 * As discussed on lkml, GENHD_FL_REMOVABLE should:
369 * - be set for removable media with permanent block devices
370 * - be unset for removable block devices with permanent media
372 * Since MMC block devices clearly fall under the second
373 * case, we do not set GENHD_FL_REMOVABLE. Userspace
374 * should use the block device creation/destruction hotplug
375 * messages to tell when the card is present.
378 sprintf(md
->disk
->disk_name
, "mmcblk%d", devidx
);
380 blk_queue_hardsect_size(md
->queue
.queue
, 1 << md
->block_bits
);
383 * The CSD capacity field is in units of read_blkbits.
384 * set_capacity takes units of 512 bytes.
386 set_capacity(md
->disk
, card
->csd
.capacity
<< (card
->csd
.read_blkbits
- 9));
398 mmc_blk_set_blksize(struct mmc_blk_data
*md
, struct mmc_card
*card
)
400 struct mmc_command cmd
;
403 mmc_card_claim_host(card
);
404 cmd
.opcode
= MMC_SET_BLOCKLEN
;
405 cmd
.arg
= 1 << md
->block_bits
;
406 cmd
.flags
= MMC_RSP_R1
| MMC_CMD_AC
;
407 err
= mmc_wait_for_cmd(card
->host
, &cmd
, 5);
408 mmc_card_release_host(card
);
411 printk(KERN_ERR
"%s: unable to set block size to %d: %d\n",
412 md
->disk
->disk_name
, cmd
.arg
, err
);
419 static int mmc_blk_probe(struct mmc_card
*card
)
421 struct mmc_blk_data
*md
;
425 * Check that the card supports the command class(es) we need.
427 if (!(card
->csd
.cmdclass
& CCC_BLOCK_READ
))
430 md
= mmc_blk_alloc(card
);
434 err
= mmc_blk_set_blksize(md
, card
);
438 printk(KERN_INFO
"%s: %s %s %lluKiB %s\n",
439 md
->disk
->disk_name
, mmc_card_id(card
), mmc_card_name(card
),
440 (unsigned long long)(get_capacity(md
->disk
) >> 1),
441 md
->read_only
? "(ro)" : "");
443 mmc_set_drvdata(card
, md
);
453 static void mmc_blk_remove(struct mmc_card
*card
)
455 struct mmc_blk_data
*md
= mmc_get_drvdata(card
);
460 del_gendisk(md
->disk
);
463 * I think this is needed.
465 md
->disk
->queue
= NULL
;
467 devidx
= md
->disk
->first_minor
>> MMC_SHIFT
;
468 __clear_bit(devidx
, dev_use
);
472 mmc_set_drvdata(card
, NULL
);
476 static int mmc_blk_suspend(struct mmc_card
*card
, pm_message_t state
)
478 struct mmc_blk_data
*md
= mmc_get_drvdata(card
);
481 mmc_queue_suspend(&md
->queue
);
486 static int mmc_blk_resume(struct mmc_card
*card
)
488 struct mmc_blk_data
*md
= mmc_get_drvdata(card
);
491 mmc_blk_set_blksize(md
, card
);
492 mmc_queue_resume(&md
->queue
);
497 #define mmc_blk_suspend NULL
498 #define mmc_blk_resume NULL
501 static struct mmc_driver mmc_driver
= {
505 .probe
= mmc_blk_probe
,
506 .remove
= mmc_blk_remove
,
507 .suspend
= mmc_blk_suspend
,
508 .resume
= mmc_blk_resume
,
511 static int __init
mmc_blk_init(void)
515 res
= register_blkdev(major
, "mmc");
517 printk(KERN_WARNING
"Unable to get major %d for MMC media: %d\n",
524 return mmc_register_driver(&mmc_driver
);
530 static void __exit
mmc_blk_exit(void)
532 mmc_unregister_driver(&mmc_driver
);
533 unregister_blkdev(major
, "mmc");
536 module_init(mmc_blk_init
);
537 module_exit(mmc_blk_exit
);
539 MODULE_LICENSE("GPL");
540 MODULE_DESCRIPTION("Multimedia Card (MMC) block device driver");
542 module_param(major
, int, 0444);
543 MODULE_PARM_DESC(major
, "specify the major device number for MMC block driver");