usb: dwc2: drd: fix soft connect when gadget is unconfigured
authorFabrice Gasnier <fabrice.gasnier@foss.st.com>
Wed, 16 Feb 2022 08:12:15 +0000 (09:12 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 2 Mar 2022 10:42:55 +0000 (11:42 +0100)
commit99b2425d9178b0939ac000893c5d889d63f5234d
treea77a407a4c186bf71acbb57f20a26037afb2cc39
parentc7866880377b73a809e6f08852b0b05452ab6296
usb: dwc2: drd: fix soft connect when gadget is unconfigured

commit 32fde84362c40961726a5c91f35ad37355ccc0c6 upstream.

When the gadget driver hasn't been (yet) configured, and the cable is
connected to a HOST, the SFTDISCON gets cleared unconditionally, so the
HOST tries to enumerate it.
At the host side, this can result in a stuck USB port or worse. When
getting lucky, some dmesg can be observed at the host side:
 new high-speed USB device number ...
 device descriptor read/64, error -110

Fix it in drd, by checking the enabled flag before calling
dwc2_hsotg_core_connect(). It will be called later, once configured,
by the normal flow:
- udc_bind_to_driver
 - usb_gadget_connect
   - dwc2_hsotg_pullup
     - dwc2_hsotg_core_connect

Fixes: 17f934024e84 ("usb: dwc2: override PHY input signals with usb role switch support")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Link: https://lore.kernel.org/r/1644999135-13478-1-git-send-email-fabrice.gasnier@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/dwc2/core.h
drivers/usb/dwc2/drd.c