summaryrefslogtreecommitdiffstats
path: root/drivers/usb
diff options
context:
space:
mode:
authorAlan Stern <stern@rowland.harvard.edu>2007-07-06 14:24:27 -0400
committerGreg Kroah-Hartman <gregkh@suse.de>2007-07-12 16:34:43 -0700
commit8dfe4b14869fd185ca25ee88b02ada58a3005eaf (patch)
tree0c0c8812f1d038706bd82ff0d7b3570d67645e68 /drivers/usb
parentb0e2a705bffbfb70d9bed8b5f9094901f28d9563 (diff)
downloadop-kernel-dev-8dfe4b14869fd185ca25ee88b02ada58a3005eaf.zip
op-kernel-dev-8dfe4b14869fd185ca25ee88b02ada58a3005eaf.tar.gz
usb-storage: implement autosuspend
This patch (as930) implements autosuspend for usb-storage. It is adapted from a patch by Oliver Neukum. Autosuspend is allowed except during LUN scanning, resets, and command execution. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb')
-rw-r--r--drivers/usb/storage/scsiglue.c13
-rw-r--r--drivers/usb/storage/usb.c27
2 files changed, 29 insertions, 11 deletions
diff --git a/drivers/usb/storage/scsiglue.c b/drivers/usb/storage/scsiglue.c
index 1ba19ea..47e5607 100644
--- a/drivers/usb/storage/scsiglue.c
+++ b/drivers/usb/storage/scsiglue.c
@@ -285,10 +285,15 @@ static int device_reset(struct scsi_cmnd *srb)
US_DEBUGP("%s called\n", __FUNCTION__);
- /* lock the device pointers and do the reset */
- mutex_lock(&(us->dev_mutex));
- result = us->transport_reset(us);
- mutex_unlock(&us->dev_mutex);
+ result = usb_autopm_get_interface(us->pusb_intf);
+ if (result == 0) {
+
+ /* lock the device pointers and do the reset */
+ mutex_lock(&(us->dev_mutex));
+ result = us->transport_reset(us);
+ mutex_unlock(&us->dev_mutex);
+ usb_autopm_put_interface(us->pusb_intf);
+ }
return result < 0 ? FAILED : SUCCESS;
}
diff --git a/drivers/usb/storage/usb.c b/drivers/usb/storage/usb.c
index cf3fc91..bef8bcd 100644
--- a/drivers/usb/storage/usb.c
+++ b/drivers/usb/storage/usb.c
@@ -191,16 +191,14 @@ static int storage_suspend(struct usb_interface *iface, pm_message_t message)
{
struct us_data *us = usb_get_intfdata(iface);
+ US_DEBUGP("%s\n", __FUNCTION__);
+
/* Wait until no command is running */
mutex_lock(&us->dev_mutex);
- US_DEBUGP("%s\n", __FUNCTION__);
if (us->suspend_resume_hook)
(us->suspend_resume_hook)(us, US_SUSPEND);
- /* When runtime PM is working, we'll set a flag to indicate
- * whether we should autoresume when a SCSI request arrives. */
-
mutex_unlock(&us->dev_mutex);
return 0;
}
@@ -209,13 +207,11 @@ static int storage_resume(struct usb_interface *iface)
{
struct us_data *us = usb_get_intfdata(iface);
- mutex_lock(&us->dev_mutex);
-
US_DEBUGP("%s\n", __FUNCTION__);
+
if (us->suspend_resume_hook)
(us->suspend_resume_hook)(us, US_RESUME);
- mutex_unlock(&us->dev_mutex);
return 0;
}
@@ -313,6 +309,7 @@ static int usb_stor_control_thread(void * __us)
{
struct us_data *us = (struct us_data *)__us;
struct Scsi_Host *host = us_to_host(us);
+ int autopm_rc;
current->flags |= PF_NOFREEZE;
@@ -323,6 +320,9 @@ static int usb_stor_control_thread(void * __us)
US_DEBUGP("*** thread awakened.\n");
+ /* Autoresume the device */
+ autopm_rc = usb_autopm_get_interface(us->pusb_intf);
+
/* lock the device pointers */
mutex_lock(&(us->dev_mutex));
@@ -381,6 +381,12 @@ static int usb_stor_control_thread(void * __us)
us->srb->result = SAM_STAT_GOOD;
}
+ /* Did the autoresume fail? */
+ else if (autopm_rc < 0) {
+ US_DEBUGP("Could not wake device\n");
+ us->srb->result = DID_ERROR << 16;
+ }
+
/* we've got a command, let's do it! */
else {
US_DEBUG(usb_stor_show_command(us->srb));
@@ -423,6 +429,10 @@ SkipForAbort:
/* unlock the device pointers */
mutex_unlock(&us->dev_mutex);
+
+ /* Start an autosuspend */
+ if (autopm_rc == 0)
+ usb_autopm_put_interface(us->pusb_intf);
} /* for (;;) */
/* Wait until we are told to stop */
@@ -939,6 +949,7 @@ retry:
}
scsi_host_put(us_to_host(us));
+ usb_autopm_put_interface(us->pusb_intf);
complete_and_exit(&threads_gone, 0);
}
@@ -1028,6 +1039,7 @@ static int storage_probe(struct usb_interface *intf,
* start it up. */
scsi_host_get(us_to_host(us));
atomic_inc(&total_threads);
+ usb_autopm_get_interface(intf); /* dropped in the scanning thread */
wake_up_process(th);
return 0;
@@ -1065,6 +1077,7 @@ static struct usb_driver usb_storage_driver = {
.pre_reset = storage_pre_reset,
.post_reset = storage_post_reset,
.id_table = storage_usb_ids,
+ .supports_autosuspend = 1,
};
static int __init usb_stor_init(void)
OpenPOWER on IntegriCloud