From 03d27ade4941076b34c823d63d91dc895731a595 Mon Sep 17 00:00:00 2001 From: "Felipe F. Tonello" Date: Wed, 9 Mar 2016 19:39:30 +0000 Subject: [PATCH] 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 Signed-off-by: Felipe F. Tonello Signed-off-by: Felipe Balbi --- drivers/usb/gadget/function/f_midi.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/usb/gadget/function/f_midi.c b/drivers/usb/gadget/function/f_midi.c index 56e2dde99b03..9ad51dcab982 100644 --- a/drivers/usb/gadget/function/f_midi.c +++ b/drivers/usb/gadget/function/f_midi.c @@ -360,7 +360,9 @@ static int f_midi_set_alt(struct usb_function *f, unsigned intf, unsigned alt) /* allocate a bunch of read buffers and queue them all at once. */ for (i = 0; i < midi->qlen && err == 0; i++) { struct usb_request *req = - midi_alloc_ep_req(midi->out_ep, midi->buflen); + midi_alloc_ep_req(midi->out_ep, + max_t(unsigned, midi->buflen, + bulk_out_desc.wMaxPacketSize)); if (req == NULL) return -ENOMEM; -- 2.20.1