2022-06-22 16:15:25

by Fabrice Gasnier

Subject: [PATCH] usb: dwc2: gadget: remove D+ pull-up while no vbus with usb-role-switch

From: Amelie Delaunay <[email protected]>

When using usb-role-switch, D+ pull-up is set as soon as DTCL_SFTDISCON is
cleared, whatever the vbus valid signal state is. The pull-up should not
be set when vbus isn't present (this is determined by the drd controller).

This patch ensures that B-Session (so Peripheral role + vbus valid signal)
is valid before clearing the DCTL_SFTDISCON bit when role switch is used.
Keep original behavior when usb-role-switch isn't used.

Signed-off-by: Amelie Delaunay <[email protected]>
Signed-off-by: Fabrice Gasnier <[email protected]>
---
drivers/usb/dwc2/gadget.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index fe2a58c758610..8b15742d9e8aa 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -3594,7 +3594,8 @@ void dwc2_hsotg_core_disconnect(struct dwc2_hsotg *hsotg)
void dwc2_hsotg_core_connect(struct dwc2_hsotg *hsotg)
{
/* remove the soft-disconnect and let's go */
- dwc2_clear_bit(hsotg, DCTL, DCTL_SFTDISCON);
+ if (!hsotg->role_sw || (dwc2_readl(hsotg, GOTGCTL) & GOTGCTL_BSESVLD))
+ dwc2_clear_bit(hsotg, DCTL, DCTL_SFTDISCON);
}

/**
--
2.25.1

2022-06-24 06:09:19

by Minas Harutyunyan

Subject: Re: [PATCH] usb: dwc2: gadget: remove D+ pull-up while no vbus with usb-role-switch

On 6/22/2022 8:07 PM, Fabrice Gasnier wrote:
> From: Amelie Delaunay <[email protected]>
>
> When using usb-role-switch, D+ pull-up is set as soon as DTCL_SFTDISCON is
> cleared, whatever the vbus valid signal state is. The pull-up should not
> be set when vbus isn't present (this is determined by the drd controller).
>
> This patch ensures that B-Session (so Peripheral role + vbus valid signal)
> is valid before clearing the DCTL_SFTDISCON bit when role switch is used.
> Keep original behavior when usb-role-switch isn't used.
>
> Signed-off-by: Amelie Delaunay <[email protected]>
> Signed-off-by: Fabrice Gasnier <[email protected]>

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

> ---
> drivers/usb/dwc2/gadget.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
> index fe2a58c758610..8b15742d9e8aa 100644
> --- a/drivers/usb/dwc2/gadget.c
> +++ b/drivers/usb/dwc2/gadget.c
> @@ -3594,7 +3594,8 @@ void dwc2_hsotg_core_disconnect(struct dwc2_hsotg *hsotg)
> void dwc2_hsotg_core_connect(struct dwc2_hsotg *hsotg)
> {
> /* remove the soft-disconnect and let's go */
> - dwc2_clear_bit(hsotg, DCTL, DCTL_SFTDISCON);
> + if (!hsotg->role_sw || (dwc2_readl(hsotg, GOTGCTL) & GOTGCTL_BSESVLD))
> + dwc2_clear_bit(hsotg, DCTL, DCTL_SFTDISCON);
> }
>
> /**