From: Alan Stern Date: Thu, 1 Jun 2006 17:52:56 +0000 (-0400) Subject: [PATCH] usb-storage: use usb_reset_composite_device X-Git-Tag: v2.6.18-rc1~858^2~45 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=47104b0dd32cec467574822b0dc3517b3de3f0ad;p=linux-2.6 [PATCH] usb-storage: use usb_reset_composite_device This patch (as701) modifies usb-storage to take advantage of the new usb_reset_composite_device() API. Now we will be able to safely request port resets even if other drivers are bound to a mass-storage device. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/storage/scsiglue.c b/drivers/usb/storage/scsiglue.c index 5f11e19eaa..5715291ba5 100644 --- a/drivers/usb/storage/scsiglue.c +++ b/drivers/usb/storage/scsiglue.c @@ -286,11 +286,7 @@ static int bus_reset(struct scsi_cmnd *srb) int result; US_DEBUGP("%s called\n", __FUNCTION__); - - mutex_lock(&(us->dev_mutex)); result = usb_stor_port_reset(us); - mutex_unlock(&us->dev_mutex); - return result < 0 ? FAILED : SUCCESS; } diff --git a/drivers/usb/storage/transport.c b/drivers/usb/storage/transport.c index 038f4582ca..19b25c5caf 100644 --- a/drivers/usb/storage/transport.c +++ b/drivers/usb/storage/transport.c @@ -703,16 +703,19 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us) * device reset. */ Handle_Errors: - /* Let the SCSI layer know we are doing a reset, set the - * RESETTING bit, and clear the ABORTING bit so that the reset - * may proceed. */ + /* Set the RESETTING bit, and clear the ABORTING bit so that + * the reset may proceed. */ scsi_lock(us_to_host(us)); - usb_stor_report_bus_reset(us); set_bit(US_FLIDX_RESETTING, &us->flags); clear_bit(US_FLIDX_ABORTING, &us->flags); scsi_unlock(us_to_host(us)); + /* We must release the device lock because the pre_reset routine + * will want to acquire it. */ + mutex_unlock(&us->dev_mutex); result = usb_stor_port_reset(us); + mutex_lock(&us->dev_mutex); + if (result < 0) { scsi_lock(us_to_host(us)); usb_stor_report_device_reset(us); @@ -1196,31 +1199,30 @@ int usb_stor_Bulk_reset(struct us_data *us) 0, us->ifnum, NULL, 0); } -/* Issue a USB port reset to the device. But don't do anything if - * there's more than one interface in the device, so that other users - * are not affected. */ +/* Issue a USB port reset to the device. The caller must not hold + * us->dev_mutex. + */ int usb_stor_port_reset(struct us_data *us) { - int result, rc; + int result, rc_lock; - if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) { - result = -EIO; - US_DEBUGP("No reset during disconnect\n"); - } else if (us->pusb_dev->actconfig->desc.bNumInterfaces != 1) { - result = -EBUSY; - US_DEBUGP("Refusing to reset a multi-interface device\n"); - } else { - result = rc = - 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); + result = rc_lock = + 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); + else { + /* Were we disconnected while waiting for the lock? */ + if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) { + result = -EIO; + US_DEBUGP("No reset during disconnect\n"); } else { - result = usb_reset_device(us->pusb_dev); - if (rc) - usb_unlock_device(us->pusb_dev); - US_DEBUGP("usb_reset_device returns %d\n", result); + result = usb_reset_composite_device( + us->pusb_dev, us->pusb_intf); + US_DEBUGP("usb_reset_composite_device returns %d\n", + result); } + if (rc_lock) + usb_unlock_device(us->pusb_dev); } return result; } diff --git a/drivers/usb/storage/usb.c b/drivers/usb/storage/usb.c index 0142fe82f6..e232c7c899 100644 --- a/drivers/usb/storage/usb.c +++ b/drivers/usb/storage/usb.c @@ -220,6 +220,37 @@ static int storage_resume(struct usb_interface *iface) #endif /* CONFIG_PM */ +/* + * The next two routines get called just before and just after + * a USB port reset, whether from this driver or a different one. + */ + +static void storage_pre_reset(struct usb_interface *iface) +{ + struct us_data *us = usb_get_intfdata(iface); + + US_DEBUGP("%s\n", __FUNCTION__); + + /* Make sure no command runs during the reset */ + mutex_lock(&us->dev_mutex); +} + +static void storage_post_reset(struct usb_interface *iface) +{ + struct us_data *us = usb_get_intfdata(iface); + + US_DEBUGP("%s\n", __FUNCTION__); + + /* Report the reset to the SCSI core */ + scsi_lock(us_to_host(us)); + usb_stor_report_bus_reset(us); + scsi_unlock(us_to_host(us)); + + /* FIXME: Notify the subdrivers that they need to reinitialize + * the device */ + mutex_unlock(&us->dev_mutex); +} + /* * fill_inquiry_response takes an unsigned char array (which must * be at least 36 characters) and populates the vendor name, @@ -1002,6 +1033,8 @@ static struct usb_driver usb_storage_driver = { .suspend = storage_suspend, .resume = storage_resume, #endif + .pre_reset = storage_pre_reset, + .post_reset = storage_post_reset, .id_table = storage_usb_ids, };