5.4-stable review patch. If anyone has any objections, please let me know.
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From: William Wu william.wu@rock-chips.com
[ Upstream commit e271cc0d25015f4be6c88bd7731444644eb352c2 ]
Once the use_os_string flag is set to true for some functions (e.g. adb/mtp) which need to response the OS string, and then if we re-bind the ConfigFS gadget to use the other functions (e.g. hid) which should not to response the OS string, however, because the use_os_string flag is still true, so the usb gadget response the OS string descriptor incorrectly, this can cause the USB device to be unrecognizable on the Windows system.
An example of this as follows:
echo 1 > os_desc/use ln -s functions/ffs.adb configs/b.1/function0 start adbd echo "<udc device>" > UDC #succeed
stop adbd rm configs/b.1/function0 echo 0 > os_desc/use ln -s functions/hid.gs0 configs/b.1/function0 echo "<udc device>" > UDC #fail to connect on Windows
This patch sets the use_os_string flag to false at bind if the functions not support OS Descriptors.
Signed-off-by: William Wu william.wu@rock-chips.com Fixes: 87213d388e92 ("usb: gadget: configfs: OS String support") Link: https://lore.kernel.org/r/1755833769-25434-1-git-send-email-william.wu@rock-... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/usb/gadget/configfs.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/usb/gadget/configfs.c b/drivers/usb/gadget/configfs.c index 476a22728e8d1..d2be874af7d3c 100644 --- a/drivers/usb/gadget/configfs.c +++ b/drivers/usb/gadget/configfs.c @@ -1327,6 +1327,8 @@ static int configfs_composite_bind(struct usb_gadget *gadget, cdev->use_os_string = true; cdev->b_vendor_code = gi->b_vendor_code; memcpy(cdev->qw_sign, gi->qw_sign, OS_STRING_QW_SIGN_LEN); + } else { + cdev->use_os_string = false; }
if (gadget_is_otg(gadget) && !otg_desc[0]) {