2021-03-18 06:52:28

by Badhri Jagan Sridharan

Subject: [PATCH v1] usb: typec: tcpm: Skip sink_cap query only when VDM sm is busy

When port partner responds "Not supported" to the DiscIdentity command,
VDM state machine can remain in NVDM_STATE_ERR_TMOUT and this causes
querying sink cap to be skipped indefinitely. Hence check for
vdm_sm_running instead of checking for VDM_STATE_DONE.

Fixes: 8dc4bd073663f ("usb: typec: tcpm: Add support for Sink Fast Role SWAP(FRS)")
Signed-off-by: Badhri Jagan Sridharan <[email protected]>
---
drivers/usb/typec/tcpm/tcpm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 11d0c40bc47d..39e068d60755 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -5219,7 +5219,7 @@ static void tcpm_enable_frs_work(struct kthread_work *work)
goto unlock;

/* Send when the state machine is idle */
- if (port->state != SNK_READY || port->vdm_state != VDM_STATE_DONE || port->send_discover)
+ if (port->state != SNK_READY || port->vdm_sm_running || port->send_discover)
goto resched;

port->upcoming_state = GET_SINK_CAP;
--
2.31.0.rc2.261.g7f71774620-goog

2021-03-18 07:48:07

by Heikki Krogerus

Subject: Re: [PATCH v1] usb: typec: tcpm: Skip sink_cap query only when VDM sm is busy

On Wed, Mar 17, 2021 at 11:48:05PM -0700, Badhri Jagan Sridharan wrote:
> When port partner responds "Not supported" to the DiscIdentity command,
> VDM state machine can remain in NVDM_STATE_ERR_TMOUT and this causes
> querying sink cap to be skipped indefinitely. Hence check for
> vdm_sm_running instead of checking for VDM_STATE_DONE.
>
> Fixes: 8dc4bd073663f ("usb: typec: tcpm: Add support for Sink Fast Role SWAP(FRS)")
> Signed-off-by: Badhri Jagan Sridharan <[email protected]>

Acked-by: Heikki Krogerus <[email protected]>

> ---
> drivers/usb/typec/tcpm/tcpm.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index 11d0c40bc47d..39e068d60755 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -5219,7 +5219,7 @@ static void tcpm_enable_frs_work(struct kthread_work *work)
> goto unlock;
>
> /* Send when the state machine is idle */
> - if (port->state != SNK_READY || port->vdm_state != VDM_STATE_DONE || port->send_discover)
> + if (port->state != SNK_READY || port->vdm_sm_running || port->send_discover)
> goto resched;
>
> port->upcoming_state = GET_SINK_CAP;
> --
> 2.31.0.rc2.261.g7f71774620-goog

thanks,

--
heikki

2021-03-18 14:56:14

by Guenter Roeck

Subject: Re: [PATCH v1] usb: typec: tcpm: Skip sink_cap query only when VDM sm is busy

On 3/17/21 11:48 PM, Badhri Jagan Sridharan wrote:
> When port partner responds "Not supported" to the DiscIdentity command,
> VDM state machine can remain in NVDM_STATE_ERR_TMOUT and this causes
> querying sink cap to be skipped indefinitely. Hence check for
> vdm_sm_running instead of checking for VDM_STATE_DONE.
>
> Fixes: 8dc4bd073663f ("usb: typec: tcpm: Add support for Sink Fast Role SWAP(FRS)")
> Signed-off-by: Badhri Jagan Sridharan <[email protected]>

Reviewed-by: Guenter Roeck <[email protected]>

> ---
> drivers/usb/typec/tcpm/tcpm.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index 11d0c40bc47d..39e068d60755 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -5219,7 +5219,7 @@ static void tcpm_enable_frs_work(struct kthread_work *work)
> goto unlock;
>
> /* Send when the state machine is idle */
> - if (port->state != SNK_READY || port->vdm_state != VDM_STATE_DONE || port->send_discover)
> + if (port->state != SNK_READY || port->vdm_sm_running || port->send_discover)
> goto resched;
>
> port->upcoming_state = GET_SINK_CAP;
>