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/devfs_fs_kernel.h>
31 #include <linux/mutex.h>
33 #include <linux/mmc/card.h>
34 #include <linux/mmc/protocol.h>
36 #include <asm/system.h>
37 #include <asm/uaccess.h>
39 #include "mmc_queue.h"
42 * max 8 partitions per card
49 * There is one mmc_blk_data per slot.
54 struct mmc_queue queue;
57 unsigned int block_bits;
58 unsigned int read_only;
61 static DEFINE_MUTEX(open_lock);
63 static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk)
65 struct mmc_blk_data *md;
67 mutex_lock(&open_lock);
68 md = disk->private_data;
69 if (md && md->usage == 0)
73 mutex_unlock(&open_lock);
78 static void mmc_blk_put(struct mmc_blk_data *md)
80 mutex_lock(&open_lock);
84 mmc_cleanup_queue(&md->queue);
87 mutex_unlock(&open_lock);
90 static int mmc_blk_open(struct inode *inode, struct file *filp)
92 struct mmc_blk_data *md;
95 md = mmc_blk_get(inode->i_bdev->bd_disk);
98 check_disk_change(inode->i_bdev);
101 if ((filp->f_mode & FMODE_WRITE) && md->read_only)
108 static int mmc_blk_release(struct inode *inode, struct file *filp)
110 struct mmc_blk_data *md = inode->i_bdev->bd_disk->private_data;
117 mmc_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
119 geo->cylinders = get_capacity(bdev->bd_disk) / (4 * 16);
125 static struct block_device_operations mmc_bdops = {
126 .open = mmc_blk_open,
127 .release = mmc_blk_release,
128 .getgeo = mmc_blk_getgeo,
129 .owner = THIS_MODULE,
132 struct mmc_blk_request {
133 struct mmc_request mrq;
134 struct mmc_command cmd;
135 struct mmc_command stop;
136 struct mmc_data data;
139 static int mmc_blk_prep_rq(struct mmc_queue *mq, struct request *req)
141 struct mmc_blk_data *md = mq->data;
142 int stat = BLKPREP_OK;
145 * If we have no device, we haven't finished initialising.
147 if (!md || !mq->card) {
148 printk(KERN_ERR "%s: killing request - no device/host\n",
149 req->rq_disk->disk_name);
156 static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
158 struct mmc_blk_data *md = mq->data;
159 struct mmc_card *card = md->queue.card;
162 if (mmc_card_claim_host(card))
166 struct mmc_blk_request brq;
167 struct mmc_command cmd;
169 memset(&brq, 0, sizeof(struct mmc_blk_request));
170 brq.mrq.cmd = &brq.cmd;
171 brq.mrq.data = &brq.data;
173 brq.cmd.arg = req->sector << 9;
174 brq.cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
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;
181 brq.stop.flags = MMC_RSP_R1B | MMC_CMD_AC;
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;
187 brq.cmd.opcode = MMC_WRITE_BLOCK;
188 brq.data.flags |= MMC_DATA_WRITE;
192 if (brq.data.blocks > 1) {
193 brq.data.flags |= MMC_DATA_MULTI;
194 brq.mrq.stop = &brq.stop;
199 brq.data.sg = mq->sg;
200 brq.data.sg_len = blk_rq_map_sg(req->q, req, brq.data.sg);
202 mmc_wait_for_req(card->host, &brq.mrq);
204 printk(KERN_ERR "%s: error %d sending read/write command\n",
205 req->rq_disk->disk_name, brq.cmd.error);
209 if (brq.data.error) {
210 printk(KERN_ERR "%s: error %d transferring data\n",
211 req->rq_disk->disk_name, brq.data.error);
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);
224 cmd.opcode = MMC_SEND_STATUS;
225 cmd.arg = card->rca << 16;
226 cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
227 err = mmc_wait_for_cmd(card->host, &cmd, 5);
229 printk(KERN_ERR "%s: error %d requesting status\n",
230 req->rq_disk->disk_name, err);
233 } while (!(cmd.resp[0] & R1_READY_FOR_DATA));
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))
244 * A block was successfully transferred.
246 spin_lock_irq(&md->lock);
247 ret = end_that_request_chunk(req, 1, brq.data.bytes_xfered);
250 * The whole request completed successfully.
252 add_disk_randomness(req->rq_disk);
253 blkdev_dequeue_request(req);
254 end_that_request_last(req, 1);
256 spin_unlock_irq(&md->lock);
259 mmc_card_release_host(card);
264 mmc_card_release_host(card);
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.
272 spin_lock_irq(&md->lock);
274 ret = end_that_request_chunk(req, 0,
275 req->current_nr_sectors << 9);
278 add_disk_randomness(req->rq_disk);
279 blkdev_dequeue_request(req);
280 end_that_request_last(req, 0);
281 spin_unlock_irq(&md->lock);
286 #define MMC_NUM_MINORS (256 >> MMC_SHIFT)
288 static unsigned long dev_use[MMC_NUM_MINORS/(8*sizeof(unsigned long))];
290 static inline int mmc_blk_readonly(struct mmc_card *card)
292 return mmc_card_readonly(card) ||
293 !(card->csd.cmdclass & CCC_BLOCK_WRITE);
296 static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
298 struct mmc_blk_data *md;
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);
306 md = kmalloc(sizeof(struct mmc_blk_data), GFP_KERNEL);
312 memset(md, 0, sizeof(struct mmc_blk_data));
315 * Set the read-only status based on the supported commands
316 * and the write protect switch.
318 md->read_only = mmc_blk_readonly(card);
321 * Both SD and MMC specifications state (although a bit
322 * unclearly in the MMC case) that a block size of 512
323 * bytes must always be supported by the card.
327 md->disk = alloc_disk(1 << MMC_SHIFT);
328 if (md->disk == NULL) {
333 spin_lock_init(&md->lock);
336 ret = mmc_init_queue(&md->queue, card, &md->lock);
340 md->queue.prep_fn = mmc_blk_prep_rq;
341 md->queue.issue_fn = mmc_blk_issue_rq;
344 md->disk->major = major;
345 md->disk->first_minor = devidx << MMC_SHIFT;
346 md->disk->fops = &mmc_bdops;
347 md->disk->private_data = md;
348 md->disk->queue = md->queue.queue;
349 md->disk->driverfs_dev = &card->dev;
352 * As discussed on lkml, GENHD_FL_REMOVABLE should:
354 * - be set for removable media with permanent block devices
355 * - be unset for removable block devices with permanent media
357 * Since MMC block devices clearly fall under the second
358 * case, we do not set GENHD_FL_REMOVABLE. Userspace
359 * should use the block device creation/destruction hotplug
360 * messages to tell when the card is present.
363 sprintf(md->disk->disk_name, "mmcblk%d", devidx);
364 sprintf(md->disk->devfs_name, "mmc/blk%d", devidx);
366 blk_queue_hardsect_size(md->queue.queue, 1 << md->block_bits);
369 * The CSD capacity field is in units of read_blkbits.
370 * set_capacity takes units of 512 bytes.
372 set_capacity(md->disk, card->csd.capacity << (card->csd.read_blkbits - 9));
384 mmc_blk_set_blksize(struct mmc_blk_data *md, struct mmc_card *card)
386 struct mmc_command cmd;
389 mmc_card_claim_host(card);
390 cmd.opcode = MMC_SET_BLOCKLEN;
391 cmd.arg = 1 << md->block_bits;
392 cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
393 err = mmc_wait_for_cmd(card->host, &cmd, 5);
394 mmc_card_release_host(card);
397 printk(KERN_ERR "%s: unable to set block size to %d: %d\n",
398 md->disk->disk_name, cmd.arg, err);
405 static int mmc_blk_probe(struct mmc_card *card)
407 struct mmc_blk_data *md;
411 * Check that the card supports the command class(es) we need.
413 if (!(card->csd.cmdclass & CCC_BLOCK_READ))
416 md = mmc_blk_alloc(card);
420 err = mmc_blk_set_blksize(md, card);
424 printk(KERN_INFO "%s: %s %s %lluKiB %s\n",
425 md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
426 (unsigned long long)(get_capacity(md->disk) >> 1),
427 md->read_only ? "(ro)" : "");
429 mmc_set_drvdata(card, md);
439 static void mmc_blk_remove(struct mmc_card *card)
441 struct mmc_blk_data *md = mmc_get_drvdata(card);
446 del_gendisk(md->disk);
449 * I think this is needed.
451 md->disk->queue = NULL;
453 devidx = md->disk->first_minor >> MMC_SHIFT;
454 __clear_bit(devidx, dev_use);
458 mmc_set_drvdata(card, NULL);
462 static int mmc_blk_suspend(struct mmc_card *card, pm_message_t state)
464 struct mmc_blk_data *md = mmc_get_drvdata(card);
467 mmc_queue_suspend(&md->queue);
472 static int mmc_blk_resume(struct mmc_card *card)
474 struct mmc_blk_data *md = mmc_get_drvdata(card);
477 mmc_blk_set_blksize(md, card);
478 mmc_queue_resume(&md->queue);
483 #define mmc_blk_suspend NULL
484 #define mmc_blk_resume NULL
487 static struct mmc_driver mmc_driver = {
491 .probe = mmc_blk_probe,
492 .remove = mmc_blk_remove,
493 .suspend = mmc_blk_suspend,
494 .resume = mmc_blk_resume,
497 static int __init mmc_blk_init(void)
501 res = register_blkdev(major, "mmc");
503 printk(KERN_WARNING "Unable to get major %d for MMC media: %d\n",
511 return mmc_register_driver(&mmc_driver);
517 static void __exit mmc_blk_exit(void)
519 mmc_unregister_driver(&mmc_driver);
521 unregister_blkdev(major, "mmc");
524 module_init(mmc_blk_init);
525 module_exit(mmc_blk_exit);
527 MODULE_LICENSE("GPL");
528 MODULE_DESCRIPTION("Multimedia Card (MMC) block device driver");
530 module_param(major, int, 0444);
531 MODULE_PARM_DESC(major, "specify the major device number for MMC block driver");