From 99b79f157bff450f54931f52fc5870355455b8a9 Mon Sep 17 00:00:00 2001 From: Al Cooper Date: Mon, 6 Jul 2020 19:35:52 +0000 Subject: [PATCH] xhci: Fix enumeration issue when setting max packet size for FS devices. commit a73d9d9cfc3cfceabd91fb0b0c13e4062b6dbcd7 upstream. Unable to complete the enumeration of a USB TV Tuner device. Per XHCI spec (4.6.5), the EP state field of the input context shall be cleared for a set address command. In the special case of an FS device that has "MaxPacketSize0 = 8", the Linux XHCI driver does not do this before evaluating the context. With an XHCI controller that checks the EP state field for parameter context error this causes a problem in cases such as the device getting reset again after enumeration. When that field is cleared, the problem does not occur. This was found and fixed by Sasi Kumar. Cc: stable@vger.kernel.org Signed-off-by: Al Cooper Signed-off-by: Mathias Nyman Link: https://lore.kernel.org/r/20200624135949.22611-3-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman Signed-off-by: Yang Yingliang --- drivers/usb/host/xhci.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index cfb2f73b4cca..b0830ba5f180 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -1405,6 +1405,7 @@ static int xhci_check_maxpacket(struct xhci_hcd *xhci, unsigned int slot_id, xhci->devs[slot_id]->out_ctx, ep_index); ep_ctx = xhci_get_ep_ctx(xhci, command->in_ctx, ep_index); + ep_ctx->ep_info &= cpu_to_le32(~EP_STATE_MASK);/* must clear */ ep_ctx->ep_info2 &= cpu_to_le32(~MAX_PACKET_MASK); ep_ctx->ep_info2 |= cpu_to_le32(MAX_PACKET(max_packet_size)); -- GitLab