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>

diff --git a/drivers/memstick/core/memstick.c b/drivers/memstick/core/memstick.c
index 3c7d9a79c1ea5c13040a6f8f8c477d12b0600b57..7162f772bbfb92d1124042e666faa9d33609c274 100644 (file)
--- a/drivers/memstick/core/memstick.c
+++ b/drivers/memstick/core/memstick.c
@@ -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);
 

diff --git a/drivers/memstick/core/mspro_block.c b/drivers/memstick/core/mspro_block.c
index 477d0fb6e5883dafcaca0d273e79893c10c4173f..004ac4d176d939e295908add882a5a8adfc83a79 100644 (file)
--- a/drivers/memstick/core/mspro_block.c
+++ b/drivers/memstick/core/mspro_block.c
@@ -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;
        }
 

diff --git a/include/linux/memstick.h b/include/linux/memstick.h
index 2fe599c66d527da990761936ed141e9f9a44dd2c..a9f998a3f48b3d10a35eb0cc08d3e691fe8578e5 100644 (file)
--- a/include/linux/memstick.h
+++ b/include/linux/memstick.h
@@ -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;
 };