From: Stefan Eichenberger stefan.eichenberger@toradex.com
When usb_control_msg is used in the get_bMaxPacketSize0 function, the USB pipe does not include the endpoint device number. This can cause failures when a usb hub port is reinitialized after encountering a bad cable connection. As a result, the system logs the following error messages: usb usb2-port1: cannot reset (err = -32) usb usb2-port1: Cannot enable. Maybe the USB cable is bad? usb usb2-port1: attempt power cycle usb 2-1: new high-speed USB device number 5 using ci_hdrc usb 2-1: device descriptor read/8, error -71
The problem began after commit 85d07c556216 ("USB: core: Unite old scheme and new scheme descriptor reads"). There usb_get_device_descriptor was replaced with get_bMaxPacketSize0. Unlike usb_get_device_descriptor, the get_bMaxPacketSize0 function uses the macro usb_rcvaddr0pipe, which does not include the endpoint device number. usb_get_device_descriptor, on the other hand, used the macro usb_rcvctrlpipe, which includes the endpoint device number.
By modifying the get_bMaxPacketSize0 function to use usb_rcvctrlpipe instead of usb_rcvaddr0pipe, the issue can be resolved. This change will ensure that the endpoint device number is included in the USB pipe, preventing reinitialization failures. If the endpoint has not set the device number yet, it will still work because the device number is 0 in udev.
Cc: stable@vger.kernel.org Fixes: 85d07c556216 ("USB: core: Unite old scheme and new scheme descriptor reads") Signed-off-by: Stefan Eichenberger stefan.eichenberger@toradex.com --- Before commit 85d07c556216 ("USB: core: Unite old scheme and new scheme descriptor reads") usb_rcvaddr0pipe was used in hub_port_init. With this proposed change, usb_rcvctrlpipe will be used which includes devnum for the pipe. I'm not sure if this might have some side effects. However, my understanding is that devnum is set to the right value (might also be 0 if not initialised) before get_bMaxPacketSize0 is called. Therefore, this should work but please let me know if I'm wrong on this. --- drivers/usb/core/hub.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index c3f839637cb5..59e38780f76d 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -4698,7 +4698,6 @@ void usb_ep0_reinit(struct usb_device *udev) EXPORT_SYMBOL_GPL(usb_ep0_reinit);
#define usb_sndaddr0pipe() (PIPE_CONTROL << 30) -#define usb_rcvaddr0pipe() ((PIPE_CONTROL << 30) | USB_DIR_IN)
static int hub_set_address(struct usb_device *udev, int devnum) { @@ -4804,7 +4803,7 @@ static int get_bMaxPacketSize0(struct usb_device *udev, for (i = 0; i < GET_MAXPACKET0_TRIES; ++i) { /* Start with invalid values in case the transfer fails */ buf->bDescriptorType = buf->bMaxPacketSize0 = 0; - rc = usb_control_msg(udev, usb_rcvaddr0pipe(), + rc = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0), USB_REQ_GET_DESCRIPTOR, USB_DIR_IN, USB_DT_DEVICE << 8, 0, buf, size,