diff mbox series

[v2] usb: typec: tcpm: not sink vbus if operational current is 0mA

Message ID 20230801070110.1653394-1-xu.yang_2@nxp.com
State New
Headers show
Series [v2] usb: typec: tcpm: not sink vbus if operational current is 0mA | expand

Commit Message

Xu Yang Aug. 1, 2023, 7:01 a.m. UTC
PD3.0 Spec 6.4.1.3.1 said:
For a Sink requiring no power from the Source, the Voltage (B19-10)
shall be set to 5V and the Operational Current Shall be set to 0mA.

Therefore, we can keep sink path closed if the operational current of
the first fixed PDO is 0mA.

Signed-off-by: Xu Yang <xu.yang_2@nxp.com>

---
Changes in v2:
  - also call tcpm_set_charge() when charge is false as suggested from
    Heikki and Guenter.
---
 drivers/usb/typec/tcpm/tcpm.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

Comments

Heikki Krogerus Aug. 2, 2023, 10:57 a.m. UTC | #1
On Tue, Aug 01, 2023 at 03:01:10PM +0800, Xu Yang wrote:
> PD3.0 Spec 6.4.1.3.1 said:
> For a Sink requiring no power from the Source, the Voltage (B19-10)
> shall be set to 5V and the Operational Current Shall be set to 0mA.
> 
> Therefore, we can keep sink path closed if the operational current of
> the first fixed PDO is 0mA.
> 
> Signed-off-by: Xu Yang <xu.yang_2@nxp.com>

Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>

> ---
> Changes in v2:
>   - also call tcpm_set_charge() when charge is false as suggested from
>     Heikki and Guenter.
> ---
>  drivers/usb/typec/tcpm/tcpm.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index 829d75ebab42..d999e6984fea 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -4301,7 +4301,9 @@ static void run_state_machine(struct tcpm_port *port)
>  			if (port->slow_charger_loop && (current_lim > PD_P_SNK_STDBY_MW / 5))
>  				current_lim = PD_P_SNK_STDBY_MW / 5;
>  			tcpm_set_current_limit(port, current_lim, 5000);
> -			tcpm_set_charge(port, true);
> +			/* Not sink vbus if operational current is 0mA */
> +			tcpm_set_charge(port, !!pdo_max_current(port->snk_pdo[0]));
> +
>  			if (!port->pd_supported)
>  				tcpm_set_state(port, SNK_READY, 0);
>  			else
> @@ -4582,7 +4584,8 @@ static void run_state_machine(struct tcpm_port *port)
>  			tcpm_set_current_limit(port,
>  					       tcpm_get_current_limit(port),
>  					       5000);
> -			tcpm_set_charge(port, true);
> +			/* Not sink vbus if operational current is 0mA */
> +			tcpm_set_charge(port, !!pdo_max_current(port->snk_pdo[0]));
>  		}
>  		if (port->ams == HARD_RESET)
>  			tcpm_ams_finish(port);
> -- 
> 2.34.1
Guenter Roeck Aug. 2, 2023, 1:57 p.m. UTC | #2
On 8/1/23 00:01, Xu Yang wrote:
> PD3.0 Spec 6.4.1.3.1 said:
> For a Sink requiring no power from the Source, the Voltage (B19-10)
> shall be set to 5V and the Operational Current Shall be set to 0mA.
> 
> Therefore, we can keep sink path closed if the operational current of
> the first fixed PDO is 0mA.
> 
> Signed-off-by: Xu Yang <xu.yang_2@nxp.com>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> 
> ---
> Changes in v2:
>    - also call tcpm_set_charge() when charge is false as suggested from
>      Heikki and Guenter.
> ---
>   drivers/usb/typec/tcpm/tcpm.c | 7 +++++--
>   1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index 829d75ebab42..d999e6984fea 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -4301,7 +4301,9 @@ static void run_state_machine(struct tcpm_port *port)
>   			if (port->slow_charger_loop && (current_lim > PD_P_SNK_STDBY_MW / 5))
>   				current_lim = PD_P_SNK_STDBY_MW / 5;
>   			tcpm_set_current_limit(port, current_lim, 5000);
> -			tcpm_set_charge(port, true);
> +			/* Not sink vbus if operational current is 0mA */
> +			tcpm_set_charge(port, !!pdo_max_current(port->snk_pdo[0]));
> +
>   			if (!port->pd_supported)
>   				tcpm_set_state(port, SNK_READY, 0);
>   			else
> @@ -4582,7 +4584,8 @@ static void run_state_machine(struct tcpm_port *port)
>   			tcpm_set_current_limit(port,
>   					       tcpm_get_current_limit(port),
>   					       5000);
> -			tcpm_set_charge(port, true);
> +			/* Not sink vbus if operational current is 0mA */
> +			tcpm_set_charge(port, !!pdo_max_current(port->snk_pdo[0]));
>   		}
>   		if (port->ams == HARD_RESET)
>   			tcpm_ams_finish(port);
diff mbox series

Patch

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 829d75ebab42..d999e6984fea 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -4301,7 +4301,9 @@  static void run_state_machine(struct tcpm_port *port)
 			if (port->slow_charger_loop && (current_lim > PD_P_SNK_STDBY_MW / 5))
 				current_lim = PD_P_SNK_STDBY_MW / 5;
 			tcpm_set_current_limit(port, current_lim, 5000);
-			tcpm_set_charge(port, true);
+			/* Not sink vbus if operational current is 0mA */
+			tcpm_set_charge(port, !!pdo_max_current(port->snk_pdo[0]));
+
 			if (!port->pd_supported)
 				tcpm_set_state(port, SNK_READY, 0);
 			else
@@ -4582,7 +4584,8 @@  static void run_state_machine(struct tcpm_port *port)
 			tcpm_set_current_limit(port,
 					       tcpm_get_current_limit(port),
 					       5000);
-			tcpm_set_charge(port, true);
+			/* Not sink vbus if operational current is 0mA */
+			tcpm_set_charge(port, !!pdo_max_current(port->snk_pdo[0]));
 		}
 		if (port->ams == HARD_RESET)
 			tcpm_ams_finish(port);