>From e81a6204b9c53b1e6a2817a96f0e1b44e3c87fb4 Mon Sep 17 00:00:00 2001
From: Oliver Neukum <oliver@xxxxxxxxxx>
Date: Mon, 16 Jan 2012 09:38:04 +0100
Subject: [PATCH] SCSI:implement PM for sr
This implements basic power management for SCSI CDs.
Signed-off-by: Oliver Neukum <oneukum@xxxxxxx>
---
drivers/scsi/sr.c | 31 +++++++++++++++++++++++++++++--
1 files changed, 29 insertions(+), 2 deletions(-)
diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
index 5fc97d2..91b545b 100644
--- a/drivers/scsi/sr.c
+++ b/drivers/scsi/sr.c
@@ -508,16 +508,29 @@ static int sr_prep_fn(struct request_queue *q, struct request *rq)
static int sr_block_open(struct block_device *bdev, fmode_t mode)
{
+ struct scsi_device *sdev;
struct scsi_cd *cd;
int ret = -ENXIO;
+ int err;
mutex_lock(&sr_mutex);
cd = scsi_cd_get(bdev->bd_disk);
+ sdev = cd->device;
+
+ err = scsi_autopm_get_device(sdev);
+ if (err) {
+ ret = -EIO;
+ goto err_out;
+ }
+
if (cd) {
ret = cdrom_open(&cd->cdi, bdev, mode);
- if (ret)
+ if (ret) {
scsi_cd_put(cd);
+ scsi_autopm_put_device(sdev);
+ }
}
+err_out:
mutex_unlock(&sr_mutex);
return ret;
}
@@ -525,9 +538,12 @@ static int sr_block_open(struct block_device *bdev, fmode_t mode)
static int sr_block_release(struct gendisk *disk, fmode_t mode)
{
struct scsi_cd *cd = scsi_cd(disk);
+ struct scsi_device *sdev = cd->device;
+
mutex_lock(&sr_mutex);
cdrom_release(&cd->cdi, mode);
scsi_cd_put(cd);
+ scsi_autopm_put_device(sdev);
mutex_unlock(&sr_mutex);
return 0;
}
@@ -615,6 +631,11 @@ static int sr_open(struct cdrom_device_info *cdi, int purpose)
struct scsi_device *sdev = cd->device;
int retval;
+ retval = scsi_autopm_get_device(sdev);
+ if (retval) {
+ retval = -EIO;
+ goto pm_error_out;
+ }
/*
* If the device is in error recovery, wait until it is done.
* If the device is offline, then disallow any access to it.
@@ -626,16 +647,19 @@ static int sr_open(struct cdrom_device_info *cdi, int purpose)
return 0;
error_out:
+ scsi_autopm_put_device(sdev);
+pm_error_out:
return retval;
}
static void sr_release(struct cdrom_device_info *cdi)
{
struct scsi_cd *cd = cdi->handle;
+ struct scsi_device *sdev = cd->device;
if (cd->device->sector_size > 2048)
sr_set_blocklength(cd, 2048);
-
+ scsi_autopm_put_device(sdev);
}
static int sr_probe(struct device *dev)
@@ -715,6 +739,7 @@ static int sr_probe(struct device *dev)
dev_set_drvdata(dev, cd);
disk->flags |= GENHD_FL_REMOVABLE;
add_disk(disk);
+ scsi_autopm_put_device(sdev);
sdev_printk(KERN_DEBUG, sdev,
"Attached scsi CD-ROM %s\n", cd->cdi.name);
@@ -964,7 +989,9 @@ static void sr_kref_release(struct kref *kref)
static int sr_remove(struct device *dev)
{
struct scsi_cd *cd = dev_get_drvdata(dev);
+ struct scsi_device *sdev = cd->device;
+ scsi_autopm_get_device(sdev);
blk_queue_prep_rq(cd->device->request_queue, scsi_prep_fn);
del_gendisk(cd->disk);
--
1.7.1
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
