From 269cbcf7b72de6f0016806d4a0cec1d689b55a87 Mon Sep 17 00:00:00 2001
From: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Date: Wed, 9 Feb 2022 17:15:53 +0100
Subject: [PATCH] usb: dwc2: drd: fix soft connect when gadget is unconfigured
Git-commit: 269cbcf7b72de6f0016806d4a0cec1d689b55a87
Patch-mainline: v5.17-rc4
References: git-fixes
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@kernel.org
Reviewed-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Acked-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Link: https://lore.kernel.org/r/1644423353-17859-1-git-send-email-fabrice.gasnier@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/usb/dwc2/drd.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/dwc2/drd.c b/drivers/usb/dwc2/drd.c
index 1b39c4776369..9b6d44d90ad9 100644
--- a/drivers/usb/dwc2/drd.c
+++ b/drivers/usb/dwc2/drd.c
@@ -130,8 +130,10 @@ static int dwc2_drd_role_sw_set(struct usb_role_switch *sw, enum usb_role role)
already = dwc2_ovr_avalid(hsotg, true);
} else if (role == USB_ROLE_DEVICE) {
already = dwc2_ovr_bvalid(hsotg, true);
- /* This clear DCTL.SFTDISCON bit */
- dwc2_hsotg_core_connect(hsotg);
+ if (hsotg->enabled) {
+ /* This clear DCTL.SFTDISCON bit */
+ dwc2_hsotg_core_connect(hsotg);
+ }
} else {
if (dwc2_is_device_mode(hsotg)) {
if (!dwc2_ovr_bvalid(hsotg, false))
--
2.31.1