From: Alan Stern <stern@rowland.harvard.edu>
Date: Fri, 4 May 2007 15:53:03 +0000 (-0400)
Subject: USB: add RESET_RESUME device quirk
X-Git-Tag: v2.6.23-rc1~1083^2~126
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6bc6cff52e0c4c4c876b1b8a5750041da61ad42b;p=linux-2.6

USB: add RESET_RESUME device quirk

This patch (as888) adds a new USB device quirk for devices which are
unable to resume correctly.  By using the new code added for the
USB-persist facility, it is a simple matter to reset these devices
instead of resuming them.  To get things kicked off, a quirk entry is
added for the Philips PSC805.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index 12dd986bdf..02d6db61c9 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -24,6 +24,7 @@
 
 #include <linux/device.h>
 #include <linux/usb.h>
+#include <linux/usb/quirks.h>
 #include <linux/workqueue.h>
 #include "hcd.h"
 #include "usb.h"
@@ -835,6 +836,9 @@ static int usb_resume_device(struct usb_device *udev)
 		goto done;
 	}
 
+	if (udev->quirks & USB_QUIRK_RESET_RESUME)
+		udev->reset_resume = 1;
+
 	udriver = to_usb_device_driver(udev->dev.driver);
 	status = udriver->resume(udev);
 
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 51d2d30456..d37ad083d5 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -2939,6 +2939,11 @@ static int config_descriptors_changed(struct usb_device *udev)
  * this from a driver probe() routine after downloading new firmware.
  * For calls that might not occur during probe(), drivers should lock
  * the device using usb_lock_device_for_reset().
+ *
+ * Locking exception: This routine may also be called from within an
+ * autoresume handler.  Such usage won't conflict with other tasks
+ * holding the device lock because these tasks should always call
+ * usb_autopm_resume_device(), thereby preventing any unwanted autoresume.
  */
 int usb_reset_device(struct usb_device *udev)
 {
diff --git a/drivers/usb/core/quirks.c b/drivers/usb/core/quirks.c
index 739f520908..f37fa012f3 100644
--- a/drivers/usb/core/quirks.c
+++ b/drivers/usb/core/quirks.c
@@ -35,6 +35,9 @@ static const struct usb_device_id usb_quirk_list[] = {
 	/* Elsa MicroLink 56k (V.250) */
 	{ USB_DEVICE(0x05cc, 0x2267), .driver_info = USB_QUIRK_NO_AUTOSUSPEND },
 
+	/* Philips PSC805 audio device */
+	{ USB_DEVICE(0x0471, 0x0155), .driver_info = USB_QUIRK_RESET_RESUME },
+
 	{ }  /* terminating entry must be last */
 };
 
diff --git a/include/linux/usb/quirks.h b/include/linux/usb/quirks.h
index 6bac8faacb..8da374caf5 100644
--- a/include/linux/usb/quirks.h
+++ b/include/linux/usb/quirks.h
@@ -9,3 +9,6 @@
 
 /* string descriptors must not be fetched using a 255-byte read */
 #define USB_QUIRK_STRING_FETCH_255	0x00000002
+
+/* device can't resume correctly so reset it instead */
+#define USB_QUIRK_RESET_RESUME		0x00000004