This is a note to let you know that I've just added the patch titled
usb: dwc2: drd: fix soft connect when gadget is unconfigured
to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-linus branch.
The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.
If you have any questions about this process, please let me know.
From 32fde84362c40961726a5c91f35ad37355ccc0c6 Mon Sep 17 00:00:00 2001 From: Fabrice Gasnier fabrice.gasnier@foss.st.com Date: Wed, 16 Feb 2022 09:12:15 +0100 Subject: usb: dwc2: drd: fix soft connect when gadget is unconfigured
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@... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/dwc2/core.h | 2 ++ drivers/usb/dwc2/drd.c | 6 ++++-- 2 files changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h index 8a63da3ab39d..88c337bf564f 100644 --- a/drivers/usb/dwc2/core.h +++ b/drivers/usb/dwc2/core.h @@ -1418,6 +1418,7 @@ void dwc2_hsotg_core_connect(struct dwc2_hsotg *hsotg); void dwc2_hsotg_disconnect(struct dwc2_hsotg *dwc2); int dwc2_hsotg_set_test_mode(struct dwc2_hsotg *hsotg, int testmode); #define dwc2_is_device_connected(hsotg) (hsotg->connected) +#define dwc2_is_device_enabled(hsotg) (hsotg->enabled) int dwc2_backup_device_registers(struct dwc2_hsotg *hsotg); int dwc2_restore_device_registers(struct dwc2_hsotg *hsotg, int remote_wakeup); int dwc2_gadget_enter_hibernation(struct dwc2_hsotg *hsotg); @@ -1454,6 +1455,7 @@ static inline int dwc2_hsotg_set_test_mode(struct dwc2_hsotg *hsotg, int testmode) { return 0; } #define dwc2_is_device_connected(hsotg) (0) +#define dwc2_is_device_enabled(hsotg) (0) static inline int dwc2_backup_device_registers(struct dwc2_hsotg *hsotg) { return 0; } static inline int dwc2_restore_device_registers(struct dwc2_hsotg *hsotg, diff --git a/drivers/usb/dwc2/drd.c b/drivers/usb/dwc2/drd.c index 1b39c4776369..d8d6493bc457 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 (dwc2_is_device_enabled(hsotg)) { + /* This clear DCTL.SFTDISCON bit */ + dwc2_hsotg_core_connect(hsotg); + } } else { if (dwc2_is_device_mode(hsotg)) { if (!dwc2_ovr_bvalid(hsotg, false))