Re: [PATCH v1] usb: typec: tcpm: Disregard vbus off while in PR_SWAP_SNK_SRC_SOURCE_ON

From: Heikki Krogerus
Date: Thu Nov 26 2020 - 07:01:41 EST


On Tue, Nov 24, 2020 at 06:07:03PM -0800, Badhri Jagan Sridharan wrote:
> During PR_SWAP sequence, when TCPM is waiting in PR_SWAP_SNK_SRC_SOURCE_ON
> for the vbus source to ramp up, TCPM would prematurely exit
> PR_SWAP_SNK_SRC_SOURCE_ON and transition to SNK_UNATTACHED state when a
> vbus off notification is received. This should not be the case as vbus
> can still be off while in PR_SWAP_SNK_SRC_SOURCE_ON and the vbus source
> has PD_T_NEWSRC to ramp up.
>
> Signed-off-by: Badhri Jagan Sridharan <badhri@xxxxxxxxxx>

FWIW:

Acked-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>

> ---
> drivers/usb/typec/tcpm/tcpm.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index 4aac0efdb720..277b9d4d9c84 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -4218,6 +4218,14 @@ static void _tcpm_pd_vbus_off(struct tcpm_port *port)
> /* Do nothing, expected */
> break;
>
> + case PR_SWAP_SNK_SRC_SOURCE_ON:
> + /*
> + * Do nothing when vbus off notification is received.
> + * TCPM can wait for PD_T_NEWSRC in PR_SWAP_SNK_SRC_SOURCE_ON
> + * for the vbus source to ramp up.
> + */
> + break;
> +
> case PORT_RESET_WAIT_OFF:
> tcpm_set_state(port, tcpm_default_state(port), 0);
> break;
> --
> 2.29.2.454.gaff20da3a2-goog

thanks,

--
heikki