Re: [PATCH] usb: Clear both buffers when clearing a control transferTT buffer.

From: Sergei Shtylyov
Date: Fri Jun 28 2013 - 09:54:24 EST


Hello.

On 28-06-2013 3:10, William Gulland wrote:

Control transfers have both IN and OUT (or SETUP) packets, so when
clearing TT buffers for a control transfer it's necessary to send
two HUB_CLEAR_TT_BUFFER requests to the hub.

Signed-off-by: William Gulland <wgulland@xxxxxxxxxx>
---
drivers/usb/core/hub.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index feef935..868ad74 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -668,6 +668,15 @@ resubmit:
static inline int
hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
{
+ /* Need to clear both directions for control ep */
+ if (((devinfo >> 11) & USB_ENDPOINT_XFERTYPE_MASK) ==
+ USB_ENDPOINT_XFER_CONTROL) {
+ int status = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
+ HUB_CLEAR_TT_BUFFER, USB_RT_PORT,
+ devinfo ^ 0x8000, tt, NULL, 0, 1000);

Could you use consistent indentation style with the below call?
Also, empty line wouldn't hurt after declaration...

+ if (status)
+ return status;
+ }
return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
tt, NULL, 0, 1000);

WBR, Sergei

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