2017-08-27 06:50:59

by Badhri Jagan Sridharan

Subject: [PATCH 08/11] staging: typec: tcpm: add cc change handling in src states

In the case that the lower layer driver reports a cc change directly
from SINK state to SOURCE state, TCPM doesn't handle these cc change
in SRC_SEND_CAPABILITIES, SRC_READY states. And with SRC_ATTACHED
state, the change is not handled as the port is still considered
connected.

[49606.131672] state change DRP_TOGGLING -> SRC_ATTACH_WAIT
[49606.131701] pending state change SRC_ATTACH_WAIT -> SRC_ATTACHED @
200 ms
[49606.329952] state change SRC_ATTACH_WAIT -> SRC_ATTACHED [delayed 200
ms]
[49606.329978] polarity 0
[49606.329989] Requesting mux mode 1, config 0, polarity 0
[49606.349416] vbus:=1 charge=0
[49606.372274] pending state change SRC_ATTACHED -> SRC_UNATTACHED @ 480
ms
[49606.372431] VBUS on
[49606.372488] state change SRC_ATTACHED -> SRC_STARTUP
...
(the lower layer driver reports a direct change from source to sink)
[49606.536927] pending state change SRC_SEND_CAPABILITIES ->
SRC_SEND_CAPABILITIES @ 150 ms
[49606.547244] CC1: 2 -> 5, CC2: 0 -> 0 [state SRC_SEND_CAPABILITIES,
polarity 0, connected]

This can happen when the lower layer driver and/or the hardware
handles a portion of the Type-C state machine work, and quietly goes
through the unattached state.

Originally-from: Yueyao Zhu <[email protected]>
Signed-off-by: Badhri Jagan Sridharan <[email protected]>
---
drivers/staging/typec/tcpm.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/typec/tcpm.c b/drivers/staging/typec/tcpm.c
index 645f43ee83df..1f6827f32b29 100644
--- a/drivers/staging/typec/tcpm.c
+++ b/drivers/staging/typec/tcpm.c
@@ -2874,10 +2874,12 @@ static void _tcpm_cc_change(struct tcpm_port *port, enum typec_cc_status cc1,
tcpm_set_state(port, SRC_ATTACH_WAIT, 0);
break;
case SRC_ATTACHED:
- if (tcpm_port_is_disconnected(port))
+ case SRC_SEND_CAPABILITIES:
+ case SRC_READY:
+ if (tcpm_port_is_disconnected(port) ||
+ !tcpm_port_is_source(port))
tcpm_set_state(port, SRC_UNATTACHED, 0);
break;
-
case SNK_UNATTACHED:
if (tcpm_port_is_sink(port))
tcpm_set_state(port, SNK_ATTACH_WAIT, 0);
--
2.14.1.342.g6490525c54-goog

2017-08-27 17:25:49

by Guenter Roeck

Subject: Re: [PATCH 08/11] staging: typec: tcpm: add cc change handling in src states

On Sat, Aug 26, 2017 at 11:50:31PM -0700, Badhri Jagan Sridharan wrote:
> In the case that the lower layer driver reports a cc change directly
> from SINK state to SOURCE state, TCPM doesn't handle these cc change
> in SRC_SEND_CAPABILITIES, SRC_READY states. And with SRC_ATTACHED
> state, the change is not handled as the port is still considered
> connected.
>
> [49606.131672] state change DRP_TOGGLING -> SRC_ATTACH_WAIT
> [49606.131701] pending state change SRC_ATTACH_WAIT -> SRC_ATTACHED @
> 200 ms
> [49606.329952] state change SRC_ATTACH_WAIT -> SRC_ATTACHED [delayed 200
> ms]
> [49606.329978] polarity 0
> [49606.329989] Requesting mux mode 1, config 0, polarity 0
> [49606.349416] vbus:=1 charge=0
> [49606.372274] pending state change SRC_ATTACHED -> SRC_UNATTACHED @ 480
> ms
> [49606.372431] VBUS on
> [49606.372488] state change SRC_ATTACHED -> SRC_STARTUP
> ...
> (the lower layer driver reports a direct change from source to sink)
> [49606.536927] pending state change SRC_SEND_CAPABILITIES ->
> SRC_SEND_CAPABILITIES @ 150 ms
> [49606.547244] CC1: 2 -> 5, CC2: 0 -> 0 [state SRC_SEND_CAPABILITIES,
> polarity 0, connected]
>
> This can happen when the lower layer driver and/or the hardware
> handles a portion of the Type-C state machine work, and quietly goes
> through the unattached state.
>
> Originally-from: Yueyao Zhu <[email protected]>
> Signed-off-by: Badhri Jagan Sridharan <[email protected]>

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

> ---
> drivers/staging/typec/tcpm.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/staging/typec/tcpm.c b/drivers/staging/typec/tcpm.c
> index 645f43ee83df..1f6827f32b29 100644
> --- a/drivers/staging/typec/tcpm.c
> +++ b/drivers/staging/typec/tcpm.c
> @@ -2874,10 +2874,12 @@ static void _tcpm_cc_change(struct tcpm_port *port, enum typec_cc_status cc1,
> tcpm_set_state(port, SRC_ATTACH_WAIT, 0);
> break;
> case SRC_ATTACHED:
> - if (tcpm_port_is_disconnected(port))
> + case SRC_SEND_CAPABILITIES:
> + case SRC_READY:
> + if (tcpm_port_is_disconnected(port) ||
> + !tcpm_port_is_source(port))
> tcpm_set_state(port, SRC_UNATTACHED, 0);
> break;
> -
> case SNK_UNATTACHED:
> if (tcpm_port_is_sink(port))
> tcpm_set_state(port, SNK_ATTACH_WAIT, 0);
> --
> 2.14.1.342.g6490525c54-goog
>