usb: gadget: f_midi: Fixed a bug when buflen was smaller than wMaxPacketSize
authorFelipe F. Tonello <eu@felipetonello.com>
Wed, 9 Mar 2016 19:39:30 +0000 (19:39 +0000)
committerFelipe Balbi <felipe.balbi@linux.intel.com>
Wed, 30 Mar 2016 10:49:56 +0000 (13:49 +0300)
commit03d27ade4941076b34c823d63d91dc895731a595
tree7d43e8a7b09e206939bc87909a5d61acdd9d4d6a
parent7e8ac87a44746b03a37d296fdb3e6b5d96350952
usb: gadget: f_midi: Fixed a bug when buflen was smaller than wMaxPacketSize

buflen by default (256) is smaller than wMaxPacketSize (512) in high-speed
devices.

That caused the OUT endpoint to freeze if the host send any data packet of
length greater than 256 bytes.

This is an example dump of what happended on that enpoint:
HOST:   [DATA][Length=260][...]
DEVICE: [NAK]
HOST:   [PING]
DEVICE: [NAK]
HOST:   [PING]
DEVICE: [NAK]
...
HOST:   [PING]
DEVICE: [NAK]

This patch fixes this problem by setting the minimum usb_request's buffer size
for the OUT endpoint as its wMaxPacketSize.

Acked-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Felipe F. Tonello <eu@felipetonello.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
drivers/usb/gadget/function/f_midi.c