2 * Block driver for media (i.e., flash cards)
4 * Copyright 2002 Hewlett-Packard Company
5 * Copyright 2005-2008 Pierre Ossman
7 * Use consistent with the GNU GPL is permitted,
8 * provided that this copyright notice is
9 * preserved in its entirety in all copies and derived works.
11 * HEWLETT-PACKARD COMPANY MAKES NO WARRANTIES, EXPRESSED OR IMPLIED,
12 * AS TO THE USEFULNESS OR CORRECTNESS OF THIS CODE OR ITS
13 * FITNESS FOR ANY PARTICULAR PURPOSE.
15 * Many thanks to Alessandro Rubini and Jonathan Corbet!
17 * Author: Andrew Christian
20 #include <linux/moduleparam.h>
21 #include <linux/module.h>
22 #include <linux/init.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>
31 #include <linux/scatterlist.h>
32 #include <linux/string_helpers.h>
34 #include <linux/mmc/card.h>
35 #include <linux/mmc/host.h>
36 #include <linux/mmc/mmc.h>
37 #include <linux/mmc/sd.h>
39 #include <asm/system.h>
40 #include <asm/uaccess.h>
45 * max 8 partitions per card
48 #define MMC_NUM_MINORS (256 >> MMC_SHIFT)
50 static DECLARE_BITMAP(dev_use, MMC_NUM_MINORS);
53 * There is one mmc_blk_data per slot.
58 struct mmc_queue queue;
61 unsigned int block_bits;
62 unsigned int read_only;
65 static DEFINE_MUTEX(open_lock);
67 static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk)
69 struct mmc_blk_data *md;
71 mutex_lock(&open_lock);
72 md = disk->private_data;
73 if (md && md->usage == 0)
77 mutex_unlock(&open_lock);
82 static void mmc_blk_put(struct mmc_blk_data *md)
84 mutex_lock(&open_lock);
87 int devidx = MINOR(disk_devt(md->disk)) >> MMC_SHIFT;
88 __clear_bit(devidx, dev_use);
93 mutex_unlock(&open_lock);
96 static int mmc_blk_open(struct inode *inode, struct file *filp)
98 struct mmc_blk_data *md;
101 md = mmc_blk_get(inode->i_bdev->bd_disk);
104 check_disk_change(inode->i_bdev);
107 if ((filp->f_mode & FMODE_WRITE) && md->read_only) {
116 static int mmc_blk_release(struct inode *inode, struct file *filp)
118 struct mmc_blk_data *md = inode->i_bdev->bd_disk->private_data;
125 mmc_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
127 geo->cylinders = get_capacity(bdev->bd_disk) / (4 * 16);
133 static struct block_device_operations mmc_bdops = {
134 .open = mmc_blk_open,
135 .release = mmc_blk_release,
136 .getgeo = mmc_blk_getgeo,
137 .owner = THIS_MODULE,
140 struct mmc_blk_request {
141 struct mmc_request mrq;
142 struct mmc_command cmd;
143 struct mmc_command stop;
144 struct mmc_data data;
147 static u32 mmc_sd_num_wr_blocks(struct mmc_card *card)
152 struct mmc_request mrq;
153 struct mmc_command cmd;
154 struct mmc_data data;
155 unsigned int timeout_us;
157 struct scatterlist sg;
159 memset(&cmd, 0, sizeof(struct mmc_command));
161 cmd.opcode = MMC_APP_CMD;
162 cmd.arg = card->rca << 16;
163 cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
165 err = mmc_wait_for_cmd(card->host, &cmd, 0);
168 if (!mmc_host_is_spi(card->host) && !(cmd.resp[0] & R1_APP_CMD))
171 memset(&cmd, 0, sizeof(struct mmc_command));
173 cmd.opcode = SD_APP_SEND_NUM_WR_BLKS;
175 cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
177 memset(&data, 0, sizeof(struct mmc_data));
179 data.timeout_ns = card->csd.tacc_ns * 100;
180 data.timeout_clks = card->csd.tacc_clks * 100;
182 timeout_us = data.timeout_ns / 1000;
183 timeout_us += data.timeout_clks * 1000 /
184 (card->host->ios.clock / 1000);
186 if (timeout_us > 100000) {
187 data.timeout_ns = 100000000;
188 data.timeout_clks = 0;
193 data.flags = MMC_DATA_READ;
197 memset(&mrq, 0, sizeof(struct mmc_request));
202 sg_init_one(&sg, &blocks, 4);
204 mmc_wait_for_req(card->host, &mrq);
206 if (cmd.error || data.error)
209 blocks = ntohl(blocks);
214 static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
216 struct mmc_blk_data *md = mq->data;
217 struct mmc_card *card = md->queue.card;
218 struct mmc_blk_request brq;
219 int ret = 1, data_size, i;
220 struct scatterlist *sg;
222 mmc_claim_host(card->host);
225 struct mmc_command cmd;
226 u32 readcmd, writecmd;
228 memset(&brq, 0, sizeof(struct mmc_blk_request));
229 brq.mrq.cmd = &brq.cmd;
230 brq.mrq.data = &brq.data;
232 brq.cmd.arg = req->sector;
233 if (!mmc_card_blockaddr(card))
235 brq.cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
236 brq.data.blksz = 1 << md->block_bits;
237 brq.stop.opcode = MMC_STOP_TRANSMISSION;
239 brq.stop.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
240 brq.data.blocks = req->nr_sectors >> (md->block_bits - 9);
241 if (brq.data.blocks > card->host->max_blk_count)
242 brq.data.blocks = card->host->max_blk_count;
244 if (brq.data.blocks > 1) {
245 /* SPI multiblock writes terminate using a special
246 * token, not a STOP_TRANSMISSION request.
248 if (!mmc_host_is_spi(card->host)
249 || rq_data_dir(req) == READ)
250 brq.mrq.stop = &brq.stop;
251 readcmd = MMC_READ_MULTIPLE_BLOCK;
252 writecmd = MMC_WRITE_MULTIPLE_BLOCK;
255 readcmd = MMC_READ_SINGLE_BLOCK;
256 writecmd = MMC_WRITE_BLOCK;
259 if (rq_data_dir(req) == READ) {
260 brq.cmd.opcode = readcmd;
261 brq.data.flags |= MMC_DATA_READ;
263 brq.cmd.opcode = writecmd;
264 brq.data.flags |= MMC_DATA_WRITE;
267 mmc_set_data_timeout(&brq.data, card);
269 brq.data.sg = mq->sg;
270 brq.data.sg_len = mmc_queue_map_sg(mq);
272 mmc_queue_bounce_pre(mq);
275 * Adjust the sg list so it is the same size as the
278 if (brq.data.blocks !=
279 (req->nr_sectors >> (md->block_bits - 9))) {
280 data_size = brq.data.blocks * brq.data.blksz;
281 for_each_sg(brq.data.sg, sg, brq.data.sg_len, i) {
282 data_size -= sg->length;
283 if (data_size <= 0) {
284 sg->length += data_size;
292 mmc_wait_for_req(card->host, &brq.mrq);
294 mmc_queue_bounce_post(mq);
297 * Check for errors here, but don't jump to cmd_err
298 * until later as we need to wait for the card to leave
299 * programming mode even when things go wrong.
302 printk(KERN_ERR "%s: error %d sending read/write command\n",
303 req->rq_disk->disk_name, brq.cmd.error);
306 if (brq.data.error) {
307 printk(KERN_ERR "%s: error %d transferring data\n",
308 req->rq_disk->disk_name, brq.data.error);
311 if (brq.stop.error) {
312 printk(KERN_ERR "%s: error %d sending stop command\n",
313 req->rq_disk->disk_name, brq.stop.error);
316 if (!mmc_host_is_spi(card->host) && rq_data_dir(req) != READ) {
320 cmd.opcode = MMC_SEND_STATUS;
321 cmd.arg = card->rca << 16;
322 cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
323 err = mmc_wait_for_cmd(card->host, &cmd, 5);
325 printk(KERN_ERR "%s: error %d requesting status\n",
326 req->rq_disk->disk_name, err);
330 * Some cards mishandle the status bits,
331 * so make sure to check both the busy
332 * indication and the card state.
334 } while (!(cmd.resp[0] & R1_READY_FOR_DATA) ||
335 (R1_CURRENT_STATE(cmd.resp[0]) == 7));
338 if (cmd.resp[0] & ~0x00000900)
339 printk(KERN_ERR "%s: status = %08x\n",
340 req->rq_disk->disk_name, cmd.resp[0]);
341 if (mmc_decode_status(cmd.resp))
346 if (brq.cmd.error || brq.data.error || brq.stop.error)
350 * A block was successfully transferred.
352 spin_lock_irq(&md->lock);
353 ret = __blk_end_request(req, 0, brq.data.bytes_xfered);
354 spin_unlock_irq(&md->lock);
357 mmc_release_host(card->host);
363 * If this is an SD card and we're writing, we can first
364 * mark the known good sectors as ok.
366 * If the card is not SD, we can still ok written sectors
367 * as reported by the controller (which might be less than
368 * the real number of written sectors, but never more).
370 * For reads we just fail the entire chunk as that should
371 * be safe in all cases.
373 if (rq_data_dir(req) != READ) {
374 if (mmc_card_sd(card)) {
378 blocks = mmc_sd_num_wr_blocks(card);
379 if (blocks != (u32)-1) {
380 if (card->csd.write_partial)
381 bytes = blocks << md->block_bits;
384 spin_lock_irq(&md->lock);
385 ret = __blk_end_request(req, 0, bytes);
386 spin_unlock_irq(&md->lock);
389 spin_lock_irq(&md->lock);
390 ret = __blk_end_request(req, 0, brq.data.bytes_xfered);
391 spin_unlock_irq(&md->lock);
395 mmc_release_host(card->host);
397 spin_lock_irq(&md->lock);
399 ret = __blk_end_request(req, -EIO, blk_rq_cur_bytes(req));
400 spin_unlock_irq(&md->lock);
406 static inline int mmc_blk_readonly(struct mmc_card *card)
408 return mmc_card_readonly(card) ||
409 !(card->csd.cmdclass & CCC_BLOCK_WRITE);
412 static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
414 struct mmc_blk_data *md;
417 devidx = find_first_zero_bit(dev_use, MMC_NUM_MINORS);
418 if (devidx >= MMC_NUM_MINORS)
419 return ERR_PTR(-ENOSPC);
420 __set_bit(devidx, dev_use);
422 md = kzalloc(sizeof(struct mmc_blk_data), GFP_KERNEL);
430 * Set the read-only status based on the supported commands
431 * and the write protect switch.
433 md->read_only = mmc_blk_readonly(card);
436 * Both SD and MMC specifications state (although a bit
437 * unclearly in the MMC case) that a block size of 512
438 * bytes must always be supported by the card.
442 md->disk = alloc_disk(1 << MMC_SHIFT);
443 if (md->disk == NULL) {
448 spin_lock_init(&md->lock);
451 ret = mmc_init_queue(&md->queue, card, &md->lock);
455 md->queue.issue_fn = mmc_blk_issue_rq;
458 md->disk->major = MMC_BLOCK_MAJOR;
459 md->disk->first_minor = devidx << MMC_SHIFT;
460 md->disk->fops = &mmc_bdops;
461 md->disk->private_data = md;
462 md->disk->queue = md->queue.queue;
463 md->disk->driverfs_dev = &card->dev;
466 * As discussed on lkml, GENHD_FL_REMOVABLE should:
468 * - be set for removable media with permanent block devices
469 * - be unset for removable block devices with permanent media
471 * Since MMC block devices clearly fall under the second
472 * case, we do not set GENHD_FL_REMOVABLE. Userspace
473 * should use the block device creation/destruction hotplug
474 * messages to tell when the card is present.
477 sprintf(md->disk->disk_name, "mmcblk%d", devidx);
479 blk_queue_hardsect_size(md->queue.queue, 1 << md->block_bits);
481 if (!mmc_card_sd(card) && mmc_card_blockaddr(card)) {
483 * The EXT_CSD sector count is in number or 512 byte
486 set_capacity(md->disk, card->ext_csd.sectors);
489 * The CSD capacity field is in units of read_blkbits.
490 * set_capacity takes units of 512 bytes.
492 set_capacity(md->disk,
493 card->csd.capacity << (card->csd.read_blkbits - 9));
506 mmc_blk_set_blksize(struct mmc_blk_data *md, struct mmc_card *card)
508 struct mmc_command cmd;
511 /* Block-addressed cards ignore MMC_SET_BLOCKLEN. */
512 if (mmc_card_blockaddr(card))
515 mmc_claim_host(card->host);
516 cmd.opcode = MMC_SET_BLOCKLEN;
517 cmd.arg = 1 << md->block_bits;
518 cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
519 err = mmc_wait_for_cmd(card->host, &cmd, 5);
520 mmc_release_host(card->host);
523 printk(KERN_ERR "%s: unable to set block size to %d: %d\n",
524 md->disk->disk_name, cmd.arg, err);
531 static int mmc_blk_probe(struct mmc_card *card)
533 struct mmc_blk_data *md;
539 * Check that the card supports the command class(es) we need.
541 if (!(card->csd.cmdclass & CCC_BLOCK_READ))
544 md = mmc_blk_alloc(card);
548 err = mmc_blk_set_blksize(md, card);
552 string_get_size(get_capacity(md->disk) << 9, STRING_UNITS_2,
553 cap_str, sizeof(cap_str));
554 printk(KERN_INFO "%s: %s %s %s %s\n",
555 md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
556 cap_str, md->read_only ? "(ro)" : "");
558 mmc_set_drvdata(card, md);
568 static void mmc_blk_remove(struct mmc_card *card)
570 struct mmc_blk_data *md = mmc_get_drvdata(card);
573 /* Stop new requests from getting into the queue */
574 del_gendisk(md->disk);
576 /* Then flush out any already in there */
577 mmc_cleanup_queue(&md->queue);
581 mmc_set_drvdata(card, NULL);
585 static int mmc_blk_suspend(struct mmc_card *card, pm_message_t state)
587 struct mmc_blk_data *md = mmc_get_drvdata(card);
590 mmc_queue_suspend(&md->queue);
595 static int mmc_blk_resume(struct mmc_card *card)
597 struct mmc_blk_data *md = mmc_get_drvdata(card);
600 mmc_blk_set_blksize(md, card);
601 mmc_queue_resume(&md->queue);
606 #define mmc_blk_suspend NULL
607 #define mmc_blk_resume NULL
610 static struct mmc_driver mmc_driver = {
614 .probe = mmc_blk_probe,
615 .remove = mmc_blk_remove,
616 .suspend = mmc_blk_suspend,
617 .resume = mmc_blk_resume,
620 static int __init mmc_blk_init(void)
624 res = register_blkdev(MMC_BLOCK_MAJOR, "mmc");
628 res = mmc_register_driver(&mmc_driver);
634 unregister_blkdev(MMC_BLOCK_MAJOR, "mmc");
639 static void __exit mmc_blk_exit(void)
641 mmc_unregister_driver(&mmc_driver);
642 unregister_blkdev(MMC_BLOCK_MAJOR, "mmc");
645 module_init(mmc_blk_init);
646 module_exit(mmc_blk_exit);
648 MODULE_LICENSE("GPL");
649 MODULE_DESCRIPTION("Multimedia Card (MMC) block device driver");