[PATCH 5.15 118/177] usb: dwc2: fix STM ID/VBUS detection startup delay in dwc2_driver_probe

Greg Kroah-Hartman
2021-12-20T14:58:58Z

From: Amelie Delaunay <amelie.delaunay@foss.st.com>

commit fac6bf87c55f7f0733efb0375565fb6a50cf2caf upstream.

When activate_stm_id_vb_detection is enabled, ID and Vbus detection relies
on sensing comparators. This detection needs time to stabilize.
A delay was already applied in dwc2_resume() when reactivating the
detection, but it wasn't done in dwc2_probe().
This patch adds delay after enabling STM ID/VBUS detection. Then, ID state
is good when initializing gadget and host, and avoid to get a wrong
Connector ID Status Change interrupt.

Fixes: a415083a11cc ("usb: dwc2: add support for STM32MP15 SoCs USB OTG HS and FS")
Cc: stable <stable@vger.kernel.org>
Acked-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Link: https://lore.kernel.org/r/20211207124510.268841-1-amelie.delaunay@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/usb/dwc2/platform.c | 3 +++
1 file changed, 3 insertions(+)

--- a/drivers/usb/dwc2/platform.c
+++ b/drivers/usb/dwc2/platform.c
@@ -575,6 +575,9 @@ static int dwc2_driver_probe(struct plat
ggpio |= GGPIO_STM32_OTG_GCCFG_IDEN;
ggpio |= GGPIO_STM32_OTG_GCCFG_VBDEN;
dwc2_writel(hsotg, ggpio, GGPIO);
+
+ /* ID/VBUS detection startup time */
+ usleep_range(5000, 7000);
}

retval = dwc2_drd_init(hsotg);