diff mbox series

[v2] tcpm: During PR_SWAP, source caps should be sent only after tSwapSourceStart

Message ID 20200812001439.545655-1-badhri@google.com (mailing list archive)
State Superseded
Headers show
Series [v2] tcpm: During PR_SWAP, source caps should be sent only after tSwapSourceStart | expand

Commit Message

Badhri Jagan Sridharan Aug. 12, 2020, 12:14 a.m. UTC
From the spec:
"6.6.8.1 SwapSourceStartTimer
The SwapSourceStartTimer Shall be used by the new Source, after a Power
Role Swap or Fast Role Swap, to ensure that it does not send
Source_Capabilities Message before the new Sink is ready to receive the
Source_Capabilities Message. The new Source Shall Not send the
Source_Capabilities Message earlier than tSwapSourceStart after the
last bit of the EOP of GoodCRC Message sent in response to the PS_RDY
Message sent by the new Source indicating that its power supply is
ready."

This fixes TD.PD.CP.E3, TD.PD.CP.E4, TD.PD.CP.E5 failures

Signed-off-by: Badhri Jagan Sridharan <badhri@google.com>
---
Changes since V1:
- Comment on the permissible values of tSwapSourceStart
---
 drivers/usb/typec/tcpm/tcpm.c | 2 +-
 include/linux/usb/pd.h        | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

Comments

Guenter Roeck Aug. 12, 2020, 1:43 a.m. UTC | #1
On Tue, Aug 11, 2020 at 05:14:39PM -0700, Badhri Jagan Sridharan wrote:
> From the spec:
> "6.6.8.1 SwapSourceStartTimer
> The SwapSourceStartTimer Shall be used by the new Source, after a Power
> Role Swap or Fast Role Swap, to ensure that it does not send
> Source_Capabilities Message before the new Sink is ready to receive the
> Source_Capabilities Message. The new Source Shall Not send the
> Source_Capabilities Message earlier than tSwapSourceStart after the
> last bit of the EOP of GoodCRC Message sent in response to the PS_RDY
> Message sent by the new Source indicating that its power supply is
> ready."
> 
> This fixes TD.PD.CP.E3, TD.PD.CP.E4, TD.PD.CP.E5 failures
> 
> Signed-off-by: Badhri Jagan Sridharan <badhri@google.com>

Nit below, otherwise

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

Note that I wasn't copied on this patch and only noticed it accidentally.

Guenter

> ---
> Changes since V1:
> - Comment on the permissible values of tSwapSourceStart
> ---
>  drivers/usb/typec/tcpm/tcpm.c | 2 +-
>  include/linux/usb/pd.h        | 1 +
>  2 files changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index 3ef37202ee37..d38347bd3335 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -3555,7 +3555,7 @@ static void run_state_machine(struct tcpm_port *port)
>  		 */
>  		tcpm_set_pwr_role(port, TYPEC_SOURCE);
>  		tcpm_pd_send_control(port, PD_CTRL_PS_RDY);
> -		tcpm_set_state(port, SRC_STARTUP, 0);
> +		tcpm_set_state(port, SRC_STARTUP, PD_T_SWAP_SRC_START);
>  		break;
>  
>  	case VCONN_SWAP_ACCEPT:
> diff --git a/include/linux/usb/pd.h b/include/linux/usb/pd.h
> index b6c233e79bd4..ed5eed73ccf8 100644
> --- a/include/linux/usb/pd.h
> +++ b/include/linux/usb/pd.h
> @@ -473,6 +473,7 @@ static inline unsigned int rdo_max_power(u32 rdo)
>  #define PD_T_ERROR_RECOVERY	100	/* minimum 25 is insufficient */
>  #define PD_T_SRCSWAPSTDBY      625     /* Maximum of 650ms */
>  #define PD_T_NEWSRC            250     /* Maximum of 275ms */
> +#define PD_T_SWAP_SRC_START	20     /* Minimum of 20ms */

Odd alignment. Same as with the previous two lines which don't use tabs
either.

>  
>  #define PD_T_DRP_TRY		100	/* 75 - 150 ms */
>  #define PD_T_DRP_TRYWAIT	600	/* 400 - 800 ms */
Badhri Jagan Sridharan Aug. 12, 2020, 2:01 a.m. UTC | #2
On Tue, Aug 11, 2020 at 6:43 PM Guenter Roeck <linux@roeck-us.net> wrote:
>
> On Tue, Aug 11, 2020 at 05:14:39PM -0700, Badhri Jagan Sridharan wrote:
> > From the spec:
> > "6.6.8.1 SwapSourceStartTimer
> > The SwapSourceStartTimer Shall be used by the new Source, after a Power
> > Role Swap or Fast Role Swap, to ensure that it does not send
> > Source_Capabilities Message before the new Sink is ready to receive the
> > Source_Capabilities Message. The new Source Shall Not send the
> > Source_Capabilities Message earlier than tSwapSourceStart after the
> > last bit of the EOP of GoodCRC Message sent in response to the PS_RDY
> > Message sent by the new Source indicating that its power supply is
> > ready."
> >
> > This fixes TD.PD.CP.E3, TD.PD.CP.E4, TD.PD.CP.E5 failures
> >
> > Signed-off-by: Badhri Jagan Sridharan <badhri@google.com>
>
> Nit below, otherwise
>
> Reviewed-by: Guenter Roeck <linux@roeck-us.net>
>
> Note that I wasn't copied on this patch and only noticed it accidentally.

Apologies Guenter ! Error on my side while performing the git
send-email command.
Will make sure that I double check next time.

>
> Guenter
>
> > ---
> > Changes since V1:
> > - Comment on the permissible values of tSwapSourceStart
> > ---
> >  drivers/usb/typec/tcpm/tcpm.c | 2 +-
> >  include/linux/usb/pd.h        | 1 +
> >  2 files changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> > index 3ef37202ee37..d38347bd3335 100644
> > --- a/drivers/usb/typec/tcpm/tcpm.c
> > +++ b/drivers/usb/typec/tcpm/tcpm.c
> > @@ -3555,7 +3555,7 @@ static void run_state_machine(struct tcpm_port *port)
> >                */
> >               tcpm_set_pwr_role(port, TYPEC_SOURCE);
> >               tcpm_pd_send_control(port, PD_CTRL_PS_RDY);
> > -             tcpm_set_state(port, SRC_STARTUP, 0);
> > +             tcpm_set_state(port, SRC_STARTUP, PD_T_SWAP_SRC_START);
> >               break;
> >
> >       case VCONN_SWAP_ACCEPT:
> > diff --git a/include/linux/usb/pd.h b/include/linux/usb/pd.h
> > index b6c233e79bd4..ed5eed73ccf8 100644
> > --- a/include/linux/usb/pd.h
> > +++ b/include/linux/usb/pd.h
> > @@ -473,6 +473,7 @@ static inline unsigned int rdo_max_power(u32 rdo)
> >  #define PD_T_ERROR_RECOVERY  100     /* minimum 25 is insufficient */
> >  #define PD_T_SRCSWAPSTDBY      625     /* Maximum of 650ms */
> >  #define PD_T_NEWSRC            250     /* Maximum of 275ms */
> > +#define PD_T_SWAP_SRC_START  20     /* Minimum of 20ms */
>
> Odd alignment. Same as with the previous two lines which don't use tabs
> either.
>
> >
> >  #define PD_T_DRP_TRY         100     /* 75 - 150 ms */
> >  #define PD_T_DRP_TRYWAIT     600     /* 400 - 800 ms */
diff mbox series

Patch

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 3ef37202ee37..d38347bd3335 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -3555,7 +3555,7 @@  static void run_state_machine(struct tcpm_port *port)
 		 */
 		tcpm_set_pwr_role(port, TYPEC_SOURCE);
 		tcpm_pd_send_control(port, PD_CTRL_PS_RDY);
-		tcpm_set_state(port, SRC_STARTUP, 0);
+		tcpm_set_state(port, SRC_STARTUP, PD_T_SWAP_SRC_START);
 		break;
 
 	case VCONN_SWAP_ACCEPT:
diff --git a/include/linux/usb/pd.h b/include/linux/usb/pd.h
index b6c233e79bd4..ed5eed73ccf8 100644
--- a/include/linux/usb/pd.h
+++ b/include/linux/usb/pd.h
@@ -473,6 +473,7 @@  static inline unsigned int rdo_max_power(u32 rdo)
 #define PD_T_ERROR_RECOVERY	100	/* minimum 25 is insufficient */
 #define PD_T_SRCSWAPSTDBY      625     /* Maximum of 650ms */
 #define PD_T_NEWSRC            250     /* Maximum of 275ms */
+#define PD_T_SWAP_SRC_START	20     /* Minimum of 20ms */
 
 #define PD_T_DRP_TRY		100	/* 75 - 150 ms */
 #define PD_T_DRP_TRYWAIT	600	/* 400 - 800 ms */