2021-12-07 12:45:21

by Amelie Delaunay

Subject: [PATCH 1/1] usb: dwc2: fix STM ID/VBUS detection startup delay in dwc2_driver_probe

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")
Signed-off-by: Amelie Delaunay <[email protected]>
---
drivers/usb/dwc2/platform.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c
index a1feaa09be57..55d7fca6f95c 100644
--- a/drivers/usb/dwc2/platform.c
+++ b/drivers/usb/dwc2/platform.c
@@ -555,6 +555,9 @@ static int dwc2_driver_probe(struct platform_device *dev)
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);
--
2.25.1

2021-12-14 06:23:39

by Minas Harutyunyan

Subject: Re: [PATCH 1/1] usb: dwc2: fix STM ID/VBUS detection startup delay in dwc2_driver_probe

On 12/7/2021 4:45 PM, Amelie Delaunay wrote:
> 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")
> Signed-off-by: Amelie Delaunay <[email protected]>

Acked-by: Minas Harutyunyan <[email protected]>

> ---
> drivers/usb/dwc2/platform.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c
> index a1feaa09be57..55d7fca6f95c 100644
> --- a/drivers/usb/dwc2/platform.c
> +++ b/drivers/usb/dwc2/platform.c
> @@ -555,6 +555,9 @@ static int dwc2_driver_probe(struct platform_device *dev)
> 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);