From 8f20f2dca8b390b4fe9e40ed6196c805a3f07b66 Mon Sep 17 00:00:00 2001 From: Christian Gromm Date: Tue, 21 Nov 2017 15:05:15 +0100 Subject: [PATCH] staging: most: usb: clear functional stall on OUT endpoint For the MOST packet channel there are two dedicated USB endpoints. But internally the hardware has actually one channel for data forwarding from and to MOST. To have the hardware clean up its state machine correctly in case of an error, both USB pipes need to be reset. This patch triggers the host to also clear the OUT endpoint's halt condition in case an IN endpoint has signaled to be stalled. Signed-off-by: Christian Gromm Signed-off-by: Greg Kroah-Hartman --- drivers/staging/most/usb/usb.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/drivers/staging/most/usb/usb.c b/drivers/staging/most/usb/usb.c index 87e7fec..1169635 100644 --- a/drivers/staging/most/usb/usb.c +++ b/drivers/staging/most/usb/usb.c @@ -809,6 +809,21 @@ static void wq_clear_halt(struct work_struct *wq_obj) if (usb_clear_halt(mdev->usb_device, pipe)) dev_warn(&mdev->usb_device->dev, "Failed to reset endpoint.\n"); + /* If the functional Stall condition has been set on an + * asynchronous rx channel, we need to clear the tx channel + * too, since the hardware runs its clean-up sequence on both + * channels, as they are physically one on the network. + * + * The USB interface that exposes the asynchronous channels + * contains always two endpoints, and two only. + */ + if (mdev->conf[channel].data_type == MOST_CH_ASYNC && + mdev->conf[channel].direction == MOST_CH_RX) { + int peer = 1 - channel; + int snd_pipe = usb_sndbulkpipe(mdev->usb_device, + mdev->ep_address[peer]); + usb_clear_halt(mdev->usb_device, snd_pipe); + } mdev->is_channel_healthy[channel] = true; most_resume_enqueue(&mdev->iface, channel); mutex_unlock(&mdev->io_mutex); -- 2.7.4