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>
32 #include <linux/mmc/card.h>
33 #include <linux/mmc/protocol.h>
35 #include <asm/system.h>
36 #include <asm/uaccess.h>
38 #include "mmc_queue.h"
41 * max 8 partitions per card
48 * There is one mmc_blk_data per slot.
53 struct mmc_queue queue;
56 unsigned int block_bits;
57 unsigned int read_only;
60 static DECLARE_MUTEX(open_lock);
62 static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk)
64 struct mmc_blk_data *md;
67 md = disk->private_data;
68 if (md && md->usage == 0)
77 static void mmc_blk_put(struct mmc_blk_data *md)
83 mmc_cleanup_queue(&md->queue);
89 static int mmc_blk_open(struct inode *inode, struct file *filp)
91 struct mmc_blk_data *md;
94 md = mmc_blk_get(inode->i_bdev->bd_disk);
97 check_disk_change(inode->i_bdev);
100 if ((filp->f_mode & FMODE_WRITE) && md->read_only)
107 static int mmc_blk_release(struct inode *inode, struct file *filp)
109 struct mmc_blk_data *md = inode->i_bdev->bd_disk->private_data;
116 mmc_blk_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
118 struct block_device *bdev = inode->i_bdev;
120 if (cmd == HDIO_GETGEO) {
121 struct hd_geometry geo;
123 memset(&geo, 0, sizeof(struct hd_geometry));
125 geo.cylinders = get_capacity(bdev->bd_disk) / (4 * 16);
128 geo.start = get_start_sect(bdev);
130 return copy_to_user((void __user *)arg, &geo, sizeof(geo))
137 static struct block_device_operations mmc_bdops = {
138 .open = mmc_blk_open,
139 .release = mmc_blk_release,
140 .ioctl = mmc_blk_ioctl,
141 .owner = THIS_MODULE,
144 struct mmc_blk_request {
145 struct mmc_request mrq;
146 struct mmc_command cmd;
147 struct mmc_command stop;
148 struct mmc_data data;
151 static int mmc_blk_prep_rq(struct mmc_queue *mq, struct request *req)
153 struct mmc_blk_data *md = mq->data;
154 int stat = BLKPREP_OK;
157 * If we have no device, we haven't finished initialising.
159 if (!md || !mq->card) {
160 printk(KERN_ERR "%s: killing request - no device/host\n",
161 req->rq_disk->disk_name);
168 static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
170 struct mmc_blk_data *md = mq->data;
171 struct mmc_card *card = md->queue.card;
174 if (mmc_card_claim_host(card))
178 struct mmc_blk_request brq;
179 struct mmc_command cmd;
181 memset(&brq, 0, sizeof(struct mmc_blk_request));
182 brq.mrq.cmd = &brq.cmd;
183 brq.mrq.data = &brq.data;
185 brq.cmd.arg = req->sector << 9;
186 brq.cmd.flags = MMC_RSP_R1;
187 brq.data.timeout_ns = card->csd.tacc_ns * 10;
188 brq.data.timeout_clks = card->csd.tacc_clks * 10;
189 brq.data.blksz_bits = md->block_bits;
190 brq.data.blocks = req->nr_sectors >> (md->block_bits - 9);
191 brq.stop.opcode = MMC_STOP_TRANSMISSION;
193 brq.stop.flags = MMC_RSP_R1B;
195 if (rq_data_dir(req) == READ) {
196 brq.cmd.opcode = brq.data.blocks > 1 ? MMC_READ_MULTIPLE_BLOCK : MMC_READ_SINGLE_BLOCK;
197 brq.data.flags |= MMC_DATA_READ;
199 brq.cmd.opcode = MMC_WRITE_BLOCK;
200 brq.data.flags |= MMC_DATA_WRITE;
204 if (brq.data.blocks > 1) {
205 brq.data.flags |= MMC_DATA_MULTI;
206 brq.mrq.stop = &brq.stop;
211 brq.data.sg = mq->sg;
212 brq.data.sg_len = blk_rq_map_sg(req->q, req, brq.data.sg);
214 mmc_wait_for_req(card->host, &brq.mrq);
216 printk(KERN_ERR "%s: error %d sending read/write command\n",
217 req->rq_disk->disk_name, brq.cmd.error);
221 if (brq.data.error) {
222 printk(KERN_ERR "%s: error %d transferring data\n",
223 req->rq_disk->disk_name, brq.data.error);
227 if (brq.stop.error) {
228 printk(KERN_ERR "%s: error %d sending stop command\n",
229 req->rq_disk->disk_name, brq.stop.error);
236 cmd.opcode = MMC_SEND_STATUS;
237 cmd.arg = card->rca << 16;
238 cmd.flags = MMC_RSP_R1;
239 err = mmc_wait_for_cmd(card->host, &cmd, 5);
241 printk(KERN_ERR "%s: error %d requesting status\n",
242 req->rq_disk->disk_name, err);
245 } while (!(cmd.resp[0] & R1_READY_FOR_DATA));
248 if (cmd.resp[0] & ~0x00000900)
249 printk(KERN_ERR "%s: status = %08x\n",
250 req->rq_disk->disk_name, cmd.resp[0]);
251 if (mmc_decode_status(cmd.resp))
256 * A block was successfully transferred.
258 spin_lock_irq(&md->lock);
259 ret = end_that_request_chunk(req, 1, brq.data.bytes_xfered);
262 * The whole request completed successfully.
264 add_disk_randomness(req->rq_disk);
265 blkdev_dequeue_request(req);
266 end_that_request_last(req, 1);
268 spin_unlock_irq(&md->lock);
271 mmc_card_release_host(card);
276 mmc_card_release_host(card);
279 * This is a little draconian, but until we get proper
280 * error handling sorted out here, its the best we can
281 * do - especially as some hosts have no idea how much
282 * data was transferred before the error occurred.
284 spin_lock_irq(&md->lock);
286 ret = end_that_request_chunk(req, 0,
287 req->current_nr_sectors << 9);
290 add_disk_randomness(req->rq_disk);
291 blkdev_dequeue_request(req);
292 end_that_request_last(req, 0);
293 spin_unlock_irq(&md->lock);
298 #define MMC_NUM_MINORS (256 >> MMC_SHIFT)
300 static unsigned long dev_use[MMC_NUM_MINORS/(8*sizeof(unsigned long))];
302 static inline int mmc_blk_readonly(struct mmc_card *card)
304 return mmc_card_readonly(card) ||
305 !(card->csd.cmdclass & CCC_BLOCK_WRITE);
308 static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
310 struct mmc_blk_data *md;
313 devidx = find_first_zero_bit(dev_use, MMC_NUM_MINORS);
314 if (devidx >= MMC_NUM_MINORS)
315 return ERR_PTR(-ENOSPC);
316 __set_bit(devidx, dev_use);
318 md = kmalloc(sizeof(struct mmc_blk_data), GFP_KERNEL);
324 memset(md, 0, sizeof(struct mmc_blk_data));
327 * Set the read-only status based on the supported commands
328 * and the write protect switch.
330 md->read_only = mmc_blk_readonly(card);
333 * Figure out a workable block size. MMC cards have:
334 * - two block sizes, one for read and one for write.
335 * - may support partial reads and/or writes
336 * (allows block sizes smaller than specified)
338 md->block_bits = card->csd.read_blkbits;
339 if (card->csd.write_blkbits != card->csd.read_blkbits) {
340 if (card->csd.write_blkbits < card->csd.read_blkbits &&
341 card->csd.read_partial) {
343 * write block size is smaller than read block
344 * size, but we support partial reads, so choose
345 * the smaller write block size.
347 md->block_bits = card->csd.write_blkbits;
348 } else if (card->csd.write_blkbits > card->csd.read_blkbits &&
349 card->csd.write_partial) {
351 * read block size is smaller than write block
352 * size, but we support partial writes. Use read
357 * We don't support this configuration for writes.
359 printk(KERN_ERR "%s: unable to select block size for "
360 "writing (rb%u wb%u rp%u wp%u)\n",
362 1 << card->csd.read_blkbits,
363 1 << card->csd.write_blkbits,
364 card->csd.read_partial,
365 card->csd.write_partial);
371 * Refuse to allow block sizes smaller than 512 bytes.
373 if (md->block_bits < 9) {
374 printk(KERN_ERR "%s: unable to support block size %u\n",
375 mmc_card_id(card), 1 << md->block_bits);
380 md->disk = alloc_disk(1 << MMC_SHIFT);
381 if (md->disk == NULL) {
386 spin_lock_init(&md->lock);
389 ret = mmc_init_queue(&md->queue, card, &md->lock);
393 md->queue.prep_fn = mmc_blk_prep_rq;
394 md->queue.issue_fn = mmc_blk_issue_rq;
397 md->disk->major = major;
398 md->disk->first_minor = devidx << MMC_SHIFT;
399 md->disk->fops = &mmc_bdops;
400 md->disk->private_data = md;
401 md->disk->queue = md->queue.queue;
402 md->disk->driverfs_dev = &card->dev;
405 * As discussed on lkml, GENHD_FL_REMOVABLE should:
407 * - be set for removable media with permanent block devices
408 * - be unset for removable block devices with permanent media
410 * Since MMC block devices clearly fall under the second
411 * case, we do not set GENHD_FL_REMOVABLE. Userspace
412 * should use the block device creation/destruction hotplug
413 * messages to tell when the card is present.
416 sprintf(md->disk->disk_name, "mmcblk%d", devidx);
417 sprintf(md->disk->devfs_name, "mmc/blk%d", devidx);
419 blk_queue_hardsect_size(md->queue.queue, 1 << md->block_bits);
422 * The CSD capacity field is in units of read_blkbits.
423 * set_capacity takes units of 512 bytes.
425 set_capacity(md->disk, card->csd.capacity << (card->csd.read_blkbits - 9));
437 mmc_blk_set_blksize(struct mmc_blk_data *md, struct mmc_card *card)
439 struct mmc_command cmd;
442 mmc_card_claim_host(card);
443 cmd.opcode = MMC_SET_BLOCKLEN;
444 cmd.arg = 1 << md->block_bits;
445 cmd.flags = MMC_RSP_R1;
446 err = mmc_wait_for_cmd(card->host, &cmd, 5);
447 mmc_card_release_host(card);
450 printk(KERN_ERR "%s: unable to set block size to %d: %d\n",
451 md->disk->disk_name, cmd.arg, err);
458 static int mmc_blk_probe(struct mmc_card *card)
460 struct mmc_blk_data *md;
464 * Check that the card supports the command class(es) we need.
466 if (!(card->csd.cmdclass & CCC_BLOCK_READ))
469 md = mmc_blk_alloc(card);
473 err = mmc_blk_set_blksize(md, card);
477 printk(KERN_INFO "%s: %s %s %luKiB %s\n",
478 md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
479 get_capacity(md->disk) >> 1, md->read_only ? "(ro)" : "");
481 mmc_set_drvdata(card, md);
491 static void mmc_blk_remove(struct mmc_card *card)
493 struct mmc_blk_data *md = mmc_get_drvdata(card);
498 del_gendisk(md->disk);
501 * I think this is needed.
503 md->disk->queue = NULL;
505 devidx = md->disk->first_minor >> MMC_SHIFT;
506 __clear_bit(devidx, dev_use);
510 mmc_set_drvdata(card, NULL);
514 static int mmc_blk_suspend(struct mmc_card *card, pm_message_t state)
516 struct mmc_blk_data *md = mmc_get_drvdata(card);
519 mmc_queue_suspend(&md->queue);
524 static int mmc_blk_resume(struct mmc_card *card)
526 struct mmc_blk_data *md = mmc_get_drvdata(card);
529 mmc_blk_set_blksize(md, card);
530 mmc_queue_resume(&md->queue);
535 #define mmc_blk_suspend NULL
536 #define mmc_blk_resume NULL
539 static struct mmc_driver mmc_driver = {
543 .probe = mmc_blk_probe,
544 .remove = mmc_blk_remove,
545 .suspend = mmc_blk_suspend,
546 .resume = mmc_blk_resume,
549 static int __init mmc_blk_init(void)
553 res = register_blkdev(major, "mmc");
555 printk(KERN_WARNING "Unable to get major %d for MMC media: %d\n",
563 return mmc_register_driver(&mmc_driver);
569 static void __exit mmc_blk_exit(void)
571 mmc_unregister_driver(&mmc_driver);
573 unregister_blkdev(major, "mmc");
576 module_init(mmc_blk_init);
577 module_exit(mmc_blk_exit);
579 MODULE_LICENSE("GPL");
580 MODULE_DESCRIPTION("Multimedia Card (MMC) block device driver");
582 module_param(major, int, 0444);
583 MODULE_PARM_DESC(major, "specify the major device number for MMC block driver");