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;
161 struct mmc_blk_request brq;
164 if (mmc_card_claim_host(card))
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);
284 * For writes and where the host claims to support proper
285 * error reporting, we first ok the successful blocks.
287 * For reads we just fail the entire chunk as that should
288 * be safe in all cases.
290 if (rq_data_dir(req) != READ &&
291 (card->host->caps & MMC_CAP_MULTIWRITE)) {
292 spin_lock_irq(&md->lock);
293 ret = end_that_request_chunk(req, 1, brq.data.bytes_xfered);
294 spin_unlock_irq(&md->lock);
297 spin_lock_irq(&md->lock);
299 ret = end_that_request_chunk(req, 0,
300 req->current_nr_sectors << 9);
303 add_disk_randomness(req->rq_disk);
304 blkdev_dequeue_request(req);
305 end_that_request_last(req, 0);
306 spin_unlock_irq(&md->lock);
311 #define MMC_NUM_MINORS (256 >> MMC_SHIFT)
313 static unsigned long dev_use[MMC_NUM_MINORS/(8*sizeof(unsigned long))];
315 static inline int mmc_blk_readonly(struct mmc_card *card)
317 return mmc_card_readonly(card) ||
318 !(card->csd.cmdclass & CCC_BLOCK_WRITE);
321 static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
323 struct mmc_blk_data *md;
326 devidx = find_first_zero_bit(dev_use, MMC_NUM_MINORS);
327 if (devidx >= MMC_NUM_MINORS)
328 return ERR_PTR(-ENOSPC);
329 __set_bit(devidx, dev_use);
331 md = kmalloc(sizeof(struct mmc_blk_data), GFP_KERNEL);
337 memset(md, 0, sizeof(struct mmc_blk_data));
340 * Set the read-only status based on the supported commands
341 * and the write protect switch.
343 md->read_only = mmc_blk_readonly(card);
346 * Both SD and MMC specifications state (although a bit
347 * unclearly in the MMC case) that a block size of 512
348 * bytes must always be supported by the card.
352 md->disk = alloc_disk(1 << MMC_SHIFT);
353 if (md->disk == NULL) {
358 spin_lock_init(&md->lock);
361 ret = mmc_init_queue(&md->queue, card, &md->lock);
365 md->queue.prep_fn = mmc_blk_prep_rq;
366 md->queue.issue_fn = mmc_blk_issue_rq;
369 md->disk->major = major;
370 md->disk->first_minor = devidx << MMC_SHIFT;
371 md->disk->fops = &mmc_bdops;
372 md->disk->private_data = md;
373 md->disk->queue = md->queue.queue;
374 md->disk->driverfs_dev = &card->dev;
377 * As discussed on lkml, GENHD_FL_REMOVABLE should:
379 * - be set for removable media with permanent block devices
380 * - be unset for removable block devices with permanent media
382 * Since MMC block devices clearly fall under the second
383 * case, we do not set GENHD_FL_REMOVABLE. Userspace
384 * should use the block device creation/destruction hotplug
385 * messages to tell when the card is present.
388 sprintf(md->disk->disk_name, "mmcblk%d", devidx);
390 blk_queue_hardsect_size(md->queue.queue, 1 << md->block_bits);
393 * The CSD capacity field is in units of read_blkbits.
394 * set_capacity takes units of 512 bytes.
396 set_capacity(md->disk, card->csd.capacity << (card->csd.read_blkbits - 9));
408 mmc_blk_set_blksize(struct mmc_blk_data *md, struct mmc_card *card)
410 struct mmc_command cmd;
413 mmc_card_claim_host(card);
414 cmd.opcode = MMC_SET_BLOCKLEN;
415 cmd.arg = 1 << md->block_bits;
416 cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
417 err = mmc_wait_for_cmd(card->host, &cmd, 5);
418 mmc_card_release_host(card);
421 printk(KERN_ERR "%s: unable to set block size to %d: %d\n",
422 md->disk->disk_name, cmd.arg, err);
429 static int mmc_blk_probe(struct mmc_card *card)
431 struct mmc_blk_data *md;
435 * Check that the card supports the command class(es) we need.
437 if (!(card->csd.cmdclass & CCC_BLOCK_READ))
440 md = mmc_blk_alloc(card);
444 err = mmc_blk_set_blksize(md, card);
448 printk(KERN_INFO "%s: %s %s %lluKiB %s\n",
449 md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
450 (unsigned long long)(get_capacity(md->disk) >> 1),
451 md->read_only ? "(ro)" : "");
453 mmc_set_drvdata(card, md);
463 static void mmc_blk_remove(struct mmc_card *card)
465 struct mmc_blk_data *md = mmc_get_drvdata(card);
470 del_gendisk(md->disk);
473 * I think this is needed.
475 md->disk->queue = NULL;
477 devidx = md->disk->first_minor >> MMC_SHIFT;
478 __clear_bit(devidx, dev_use);
482 mmc_set_drvdata(card, NULL);
486 static int mmc_blk_suspend(struct mmc_card *card, pm_message_t state)
488 struct mmc_blk_data *md = mmc_get_drvdata(card);
491 mmc_queue_suspend(&md->queue);
496 static int mmc_blk_resume(struct mmc_card *card)
498 struct mmc_blk_data *md = mmc_get_drvdata(card);
501 mmc_blk_set_blksize(md, card);
502 mmc_queue_resume(&md->queue);
507 #define mmc_blk_suspend NULL
508 #define mmc_blk_resume NULL
511 static struct mmc_driver mmc_driver = {
515 .probe = mmc_blk_probe,
516 .remove = mmc_blk_remove,
517 .suspend = mmc_blk_suspend,
518 .resume = mmc_blk_resume,
521 static int __init mmc_blk_init(void)
525 res = register_blkdev(major, "mmc");
527 printk(KERN_WARNING "Unable to get major %d for MMC media: %d\n",
534 return mmc_register_driver(&mmc_driver);
540 static void __exit mmc_blk_exit(void)
542 mmc_unregister_driver(&mmc_driver);
543 unregister_blkdev(major, "mmc");
546 module_init(mmc_blk_init);
547 module_exit(mmc_blk_exit);
549 MODULE_LICENSE("GPL");
550 MODULE_DESCRIPTION("Multimedia Card (MMC) block device driver");
552 module_param(major, int, 0444);
553 MODULE_PARM_DESC(major, "specify the major device number for MMC block driver");