memstick: add "start" and "stop" methods to memstick device

In some cases it may be desirable to ensure that associated driver is not
going to access the media in some period of time.  "start" and "stop"
methods are provided therefore to allow it.

Signed-off-by: Alex Dubov <oakad@yahoo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Alex Dubov 2008-07-25 19:45:01 -07:00 committed by Linus Torvalds
parent b77899985b
commit 17017d8d2c
3 changed files with 45 additions and 3 deletions

View file

@ -433,8 +433,11 @@ static void memstick_check(struct work_struct *work)
dev_dbg(&host->dev, "memstick_check started\n");
mutex_lock(&host->lock);
if (!host->card)
memstick_power_on(host);
if (!host->card) {
if (memstick_power_on(host))
goto out_power_off;
} else
host->card->stop(host->card);
card = memstick_alloc_card(host);
@ -452,7 +455,8 @@ static void memstick_check(struct work_struct *work)
|| !(host->card->check(host->card))) {
device_unregister(&host->card->dev);
host->card = NULL;
}
} else
host->card->start(host->card);
}
if (!host->card) {
@ -465,6 +469,7 @@ static void memstick_check(struct work_struct *work)
kfree(card);
}
out_power_off:
if (!host->card)
host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);

View file

@ -752,6 +752,37 @@ static int mspro_block_has_request(struct mspro_block_data *msb)
return rc;
}
static void mspro_block_stop(struct memstick_dev *card)
{
struct mspro_block_data *msb = memstick_get_drvdata(card);
int rc = 0;
unsigned long flags;
while (1) {
spin_lock_irqsave(&msb->q_lock, flags);
if (!msb->has_request) {
blk_stop_queue(msb->queue);
rc = 1;
}
spin_unlock_irqrestore(&msb->q_lock, flags);
if (rc)
break;
wait_for_completion(&card->mrq_complete);
}
}
static void mspro_block_start(struct memstick_dev *card)
{
struct mspro_block_data *msb = memstick_get_drvdata(card);
unsigned long flags;
spin_lock_irqsave(&msb->q_lock, flags);
blk_start_queue(msb->queue);
spin_unlock_irqrestore(&msb->q_lock, flags);
}
static int mspro_block_queue_thread(void *data)
{
struct memstick_dev *card = data;
@ -1272,6 +1303,8 @@ static int mspro_block_probe(struct memstick_dev *card)
rc = mspro_block_init_disk(card);
if (!rc) {
card->check = mspro_block_check_card;
card->stop = mspro_block_stop;
card->start = mspro_block_start;
return 0;
}

View file

@ -263,6 +263,10 @@ struct memstick_dev {
/* Get next request from the media driver. */
int (*next_request)(struct memstick_dev *card,
struct memstick_request **mrq);
/* Tell the media driver to stop doing things */
void (*stop)(struct memstick_dev *card);
/* Allow the media driver to continue */
void (*start)(struct memstick_dev *card);
struct device dev;
};