diff options
Diffstat (limited to 'Documentation/usb/callbacks.txt')
| -rw-r--r-- | Documentation/usb/callbacks.txt | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/Documentation/usb/callbacks.txt b/Documentation/usb/callbacks.txt index 7c812411945..9e85846bdb9 100644 --- a/Documentation/usb/callbacks.txt +++ b/Documentation/usb/callbacks.txt @@ -65,7 +65,7 @@ Accept or decline an interface. If you accept the device return 0, otherwise -ENODEV or -ENXIO. Other error codes should be used only if a genuine error occurred during initialisation which prevented a driver from accepting a device that would else have been accepted. -You are strongly encouraged to use usbcore'sfacility, +You are strongly encouraged to use usbcore's facility, usb_set_intfdata(), to associate a data structure with an interface, so that you know which internal state and identity you associate with a particular interface. The device will not be suspended and you may do IO @@ -95,9 +95,11 @@ pre_reset int (*pre_reset)(struct usb_interface *intf); -Another driver or user space is triggering a reset on the device which -contains the interface passed as an argument. Cease IO and save any -device state you need to restore. +A driver or user space is triggering a reset on the device which +contains the interface passed as an argument. Cease IO, wait for all +outstanding URBs to complete, and save any device state you need to +restore. No more URBs may be submitted until the post_reset method +is called. If you need to allocate memory here, use GFP_NOIO or GFP_ATOMIC, if you are in atomic context. |