-
Samuel Thibault authored
[ Upstream commit 3243367b ] Some USB 2.0 devices erroneously report millisecond values in bInterval. The generic config code manages to catch most of them, but in some cases it's not completely enough. The case at stake here is a USB 2.0 braille device, which wants to announce 10ms and thus sets bInterval to 10, but with the USB 2.0 computation that yields to 64ms. It happens that one can type fast enough to reach this interval and get the device buffers overflown, leading to problematic latencies. The generic config code does not catch this case because the 64ms is considered a sane enough value. This change thus adds a USB_QUIRK_LINEAR_FRAME_INTR_BINTERVAL quirk to mark devices which actually report milliseconds in bInterval, and marks Vario Ultra devices as needing it. Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org> Acked-by: Alan Stern <stern@rowland.harvard.edu> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
ed4b286d