From 939a2e12ccbdd3f6fbff6111b03f98f46f7d7e1f 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 56e2dde99b034..9ad51dcab9824 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; -- 2.39.5