[SCSI] sd: implement START/STOP management
Implement SBC START/STOP management. sdev->mange_start_stop is added.
When it's set to one, sd STOPs the device on suspend and shutdown and
STARTs it on resume. sdev->manage_start_stop defaults is in sdev
instead of scsi_disk cdev to allow ->slave_config() override the
default configuration but is exported under scsi_disk sysfs node as
sdev->allow_restart is.
When manage_start_stop is zero (the default value), this patch doesn't
introduce any behavior change.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Rejections fixed and
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index c275dca..96db51c 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -278,6 +278,7 @@
static int scsi_bus_suspend(struct device * dev, pm_message_t state)
{
+ struct device_driver *drv = dev->driver;
struct scsi_device *sdev = to_scsi_device(dev);
struct scsi_host_template *sht = sdev->host->hostt;
int err;
@@ -286,23 +287,45 @@
if (err)
return err;
- if (sht->suspend)
- err = sht->suspend(sdev, state);
+ /* call HLD suspend first */
+ if (drv && drv->suspend) {
+ err = drv->suspend(dev, state);
+ if (err)
+ return err;
+ }
- return err;
+ /* then, call host suspend */
+ if (sht->suspend) {
+ err = sht->suspend(sdev, state);
+ if (err) {
+ if (drv && drv->resume)
+ drv->resume(dev);
+ return err;
+ }
+ }
+
+ return 0;
}
static int scsi_bus_resume(struct device * dev)
{
+ struct device_driver *drv = dev->driver;
struct scsi_device *sdev = to_scsi_device(dev);
struct scsi_host_template *sht = sdev->host->hostt;
- int err = 0;
+ int err = 0, err2 = 0;
+ /* call host resume first */
if (sht->resume)
err = sht->resume(sdev);
+ /* then, call HLD resume */
+ if (drv && drv->resume)
+ err2 = drv->resume(dev);
+
scsi_device_resume(sdev);
- return err;
+
+ /* favor LLD failure */
+ return err ? err : err2;;
}
struct bus_type scsi_bus_type = {