diff options
| -rw-r--r-- | drivers/usb/core/devio.c | 3 | ||||
| -rw-r--r-- | drivers/usb/core/hub.c | 84 | ||||
| -rw-r--r-- | drivers/usb/core/usb.c | 1 | ||||
| -rw-r--r-- | include/linux/usb.h | 9 |
4 files changed, 92 insertions, 5 deletions
diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c index b04ede772f2c..df3fb57d71e6 100644 --- a/drivers/usb/core/devio.c +++ b/drivers/usb/core/devio.c @@ -823,8 +823,7 @@ static int proc_connectinfo(struct dev_state *ps, void __user *arg) static int proc_resetdevice(struct dev_state *ps) { - return usb_reset_device(ps->dev); - + return usb_reset_composite_device(ps->dev, NULL); } static int proc_setintf(struct dev_state *ps, void __user *arg) diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index f41c08946a52..37c67d7e8b84 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -3007,9 +3007,9 @@ static int config_descriptors_changed(struct usb_device *udev) * usb_reset_device - perform a USB port reset to reinitialize a device * @udev: device to reset (not in SUSPENDED or NOTATTACHED state) * - * WARNING - don't reset any device unless drivers for all of its - * interfaces are expecting that reset! Maybe some driver->reset() - * method should eventually help ensure sufficient cooperation. + * WARNING - don't use this routine to reset a composite device + * (one with multiple interfaces owned by separate drivers)! + * Use usb_reset_composite_device() instead. * * Do a port reset, reassign the device's address, and establish its * former operating configuration. If the reset fails, or the device's @@ -3125,3 +3125,81 @@ re_enumerate: hub_port_logical_disconnect(parent_hub, port1); return -ENODEV; } + +/** + * usb_reset_composite_device - warn interface drivers and perform a USB port reset + * @udev: device to reset (not in SUSPENDED or NOTATTACHED state) + * @iface: interface bound to the driver making the request (optional) + * + * Warns all drivers bound to registered interfaces (using their pre_reset + * method), performs the port reset, and then lets the drivers know that + * the reset is over (using their post_reset method). + * + * Return value is the same as for usb_reset_device(). + * + * The caller must own the device lock. For example, it's safe to use + * 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(). + * + * The interface locks are acquired during the pre_reset stage and released + * during the post_reset stage. However if iface is not NULL and is + * currently being probed, we assume that the caller already owns its + * lock. + */ +int usb_reset_composite_device(struct usb_device *udev, + struct usb_interface *iface) +{ + int ret; + struct usb_host_config *config = udev->actconfig; + + if (udev->state == USB_STATE_NOTATTACHED || + udev->state == USB_STATE_SUSPENDED) { + dev_dbg(&udev->dev, "device reset not allowed in state %d\n", + udev->state); + return -EINVAL; + } + + if (iface && iface->condition != USB_INTERFACE_BINDING) + iface = NULL; + + if (config) { + int i; + struct usb_interface *cintf; + struct usb_driver *drv; + + for (i = 0; i < config->desc.bNumInterfaces; ++i) { + cintf = config->interface[i]; + if (cintf != iface) + down(&cintf->dev.sem); + if (device_is_registered(&cintf->dev) && + cintf->dev.driver) { + drv = to_usb_driver(cintf->dev.driver); + if (drv->pre_reset) + (drv->pre_reset)(cintf); + } + } + } + + ret = usb_reset_device(udev); + + if (config) { + int i; + struct usb_interface *cintf; + struct usb_driver *drv; + + for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) { + cintf = config->interface[i]; + if (device_is_registered(&cintf->dev) && + cintf->dev.driver) { + drv = to_usb_driver(cintf->dev.driver); + if (drv->post_reset) + (drv->post_reset)(cintf); + } + if (cintf != iface) + up(&cintf->dev.sem); + } + } + + return ret; +} diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c index b7fdc1cd134a..515310751303 100644 --- a/drivers/usb/core/usb.c +++ b/drivers/usb/core/usb.c @@ -1207,6 +1207,7 @@ EXPORT_SYMBOL(usb_ifnum_to_if); EXPORT_SYMBOL(usb_altnum_to_altsetting); EXPORT_SYMBOL(usb_reset_device); +EXPORT_SYMBOL(usb_reset_composite_device); EXPORT_SYMBOL(__usb_get_extra_descriptor); diff --git a/include/linux/usb.h b/include/linux/usb.h index 317ec9f28bce..5ad30cefe7b2 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -386,6 +386,8 @@ extern int usb_lock_device_for_reset(struct usb_device *udev, /* USB port reset for device reinitialization */ extern int usb_reset_device(struct usb_device *dev); +extern int usb_reset_composite_device(struct usb_device *dev, + struct usb_interface *iface); extern struct usb_device *usb_find_device(u16 vendor_id, u16 product_id); @@ -554,6 +556,10 @@ struct usb_dynids { * do (or don't) show up otherwise in the filesystem. * @suspend: Called when the device is going to be suspended by the system. * @resume: Called when the device is being resumed by the system. + * @pre_reset: Called by usb_reset_composite_device() when the device + * is about to be reset. + * @post_reset: Called by usb_reset_composite_device() after the device + * has been reset. * @id_table: USB drivers use ID table to support hotplugging. * Export this with MODULE_DEVICE_TABLE(usb,...). This must be set * or your driver's probe function will never get called. @@ -592,6 +598,9 @@ struct usb_driver { int (*suspend) (struct usb_interface *intf, pm_message_t message); int (*resume) (struct usb_interface *intf); + void (*pre_reset) (struct usb_interface *intf); + void (*post_reset) (struct usb_interface *intf); + const struct usb_device_id *id_table; struct usb_dynids dynids; |