USB: storage: Never reset devices that will morph to an old mode

Some devices must be switched to a new mode to fully use them.
A reset would make them revert to the old mode. Therefore a reset
must not be used for error handling with such devices.

Signed-off-by: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Oliver Neukum 2009-12-18 12:14:21 +01:00 committed by Greg Kroah-Hartman
parent d1b5b5c0a8
commit 5d3987796c
3 changed files with 11 additions and 1 deletions

View File

@ -120,6 +120,7 @@ void usb_detect_quirks(struct usb_device *udev)
* for all devices. It will affect things like hub resets
* and EMF-related port disables.
*/
udev->persist_enabled = 1;
if (!(udev->quirks & USB_QUIRK_RESET_MORPHS))
udev->persist_enabled = 1;
#endif /* CONFIG_PM */
}

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@ -47,6 +47,8 @@
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/usb/quirks.h>
#include <scsi/scsi.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_device.h>
@ -1297,6 +1299,10 @@ int usb_stor_port_reset(struct us_data *us)
{
int result;
/*for these devices we must use the class specific method */
if (us->pusb_dev->quirks & USB_QUIRK_RESET_MORPHS)
return -EPERM;
result = usb_lock_device_for_reset(us->pusb_dev, us->pusb_intf);
if (result < 0)
US_DEBUGP("unable to lock device for reset: %d\n", result);

View File

@ -19,4 +19,7 @@
/* device can't handle its Configuration or Interface strings */
#define USB_QUIRK_CONFIG_INTF_STRINGS 0x00000008
/*device will morph if reset, don't use reset for handling errors */
#define USB_QUIRK_RESET_MORPHS 0x00000010
#endif /* __LINUX_USB_QUIRKS_H */