On Wed, Apr 07, 2021 at 01:07:18PM -0700, Badhri Jagan Sridharan wrote:
> tcpm_pd_build_request overwrites current_limit and supply_voltage
> even before port partner accepts the requests. This leaves stale
> values in current_limit and supply_voltage that get exported by
> "tcpm-source-psy-". Solving this problem by caching the request
> values of current limit/supply voltage in req_current_limit
> and req_supply_voltage. current_limit/supply_voltage gets updated
> once the port partner accepts the request.
>
> Fixes: f2a8aa053c176 ("typec: tcpm: Represent source supply through power_supply")
> Signed-off-by: Badhri Jagan Sridharan <badhri@xxxxxxxxxx>
> Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> Reviewed-by: Adam Thomson <Adam.Thomson.Opensource@xxxxxxxxxxx>
Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
> ---
> Changes since V1:
> * Fixed typo as suggested by Guenter Roeck.
> * Added Reviewed-by tags.
> ---
> drivers/usb/typec/tcpm/tcpm.c | 17 ++++++++++-------
> 1 file changed, 10 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index ca1fc77697fc..4ea4b30ae885 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -389,7 +389,10 @@ struct tcpm_port {
> unsigned int operating_snk_mw;
> bool update_sink_caps;
>
> - /* Requested current / voltage */
> + /* Requested current / voltage to the port partner */
> + u32 req_current_limit;
> + u32 req_supply_voltage;
> + /* Actual current / voltage limit of the local port */
> u32 current_limit;
> u32 supply_voltage;
>
> @@ -2435,8 +2438,8 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port,
> case SNK_TRANSITION_SINK:
> if (port->vbus_present) {
> tcpm_set_current_limit(port,
> - port->current_limit,
> - port->supply_voltage);
> + port->req_current_limit,
> + port->req_supply_voltage);
> port->explicit_contract = true;
> tcpm_set_auto_vbus_discharge_threshold(port,
> TYPEC_PWR_MODE_PD,
> @@ -2545,8 +2548,8 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port,
> break;
> case SNK_NEGOTIATE_PPS_CAPABILITIES:
> port->pps_data.active = true;
> - port->supply_voltage = port->pps_data.out_volt;
> - port->current_limit = port->pps_data.op_curr;
> + port->req_supply_voltage = port->pps_data.out_volt;
> + port->req_current_limit = port->pps_data.op_curr;
> tcpm_set_state(port, SNK_TRANSITION_SINK, 0);
> break;
> case SOFT_RESET_SEND:
> @@ -3195,8 +3198,8 @@ static int tcpm_pd_build_request(struct tcpm_port *port, u32 *rdo)
> flags & RDO_CAP_MISMATCH ? " [mismatch]" : "");
> }
>
> - port->current_limit = ma;
> - port->supply_voltage = mv;
> + port->req_current_limit = ma;
> + port->req_supply_voltage = mv;
>
> return 0;
> }
> --
> 2.31.1.295.g9ea45b61b8-goog
--
heikki
