diff options
author | Alan Stern <stern@rowland.harvard.edu> | 2006-06-01 17:33:42 (GMT) |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2006-06-21 22:04:15 (GMT) |
commit | 79efa097e75018a2918155f343f0e08e61ee8a8c (patch) | |
tree | 336237ca96191aeb9cac6ed8706bc479545f3108 /drivers/usb | |
parent | efcaa20525fde82bbb4fb8cd9e9016f6fabc6509 (diff) | |
download | linux-fsl-qoriq-79efa097e75018a2918155f343f0e08e61ee8a8c.tar.xz |
[PATCH] usbcore: port reset for composite devices
This patch (as699) adds usb_reset_composite_device(), a routine for
sending a USB port reset to a device with multiple interfaces owned by
different drivers. Drivers are notified about impending and completed
resets through two new methods in the usb_driver structure.
The patch modifieds the usbfs ioctl code to make it use the new routine
instead of usb_reset_device(). Follow-up patches will modify the hub,
usb-storage, and usbhid drivers so they can utilize this new API.
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/core/devio.c | 3 | ||||
-rw-r--r-- | drivers/usb/core/hub.c | 84 | ||||
-rw-r--r-- | drivers/usb/core/usb.c | 1 |
3 files changed, 83 insertions, 5 deletions
diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c index b04ede7..df3fb57d 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 f41c089..37c67d7 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 b7fdc1c..5153107 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); |