From: Alan Stern Date: Wed, 8 Nov 2017 17:23:17 +0000 (-0500) Subject: USB: usbfs: compute urb->actual_length for isochronous X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e0ec55a69450becef296d2abae2476e2db81f336;p=pandora-kernel.git USB: usbfs: compute urb->actual_length for isochronous commit 2ef47001b3ee3ded579b7532ebdcf8680e4d8c54 upstream. The USB kerneldoc says that the actual_length field "is read in non-iso completion functions", but the usbfs driver uses it for all URB types in processcompl(). Since not all of the host controller drivers set actual_length for isochronous URBs, programs using usbfs with some host controllers don't work properly. For example, Minas reports that a USB camera controlled by libusb doesn't work properly with a dwc2 controller. It doesn't seem worthwhile to change the HCDs and the documentation, since the in-kernel USB class drivers evidently don't rely on actual_length for isochronous transfers. The easiest solution is for usbfs to calculate the actual_length value for itself, by adding up the lengths of the individual packets in an isochronous transfer. Signed-off-by: Alan Stern CC: Minas Harutyunyan Reported-and-tested-by: wlf Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings --- Reading git-diff-tree failed