Re: [PATCH v1] usb: typec: tcpm: Ignore CC and vbus changes in PORT_RESET change

From: Guenter Roeck
Date: Tue Apr 14 2020 - 16:15:18 EST


On 4/14/20 5:04 AM, Heikki Krogerus wrote:
> On Thu, Apr 02, 2020 at 02:59:47PM -0700, Badhri Jagan Sridharan wrote:
>> After PORT_RESET, the port is set to the appropriate
>> default_state. Ignore processing CC changes here as this
>> could cause the port to be switched into sink states
>> by default.
>>
>> echo source > /sys/class/typec/port0/port_type
>>
>> Before:
>> [ 154.528547] pending state change PORT_RESET -> PORT_RESET_WAIT_OFF @ 100 ms
>> [ 154.528560] CC1: 0 -> 0, CC2: 3 -> 0 [state PORT_RESET, polarity 0, disconnected]
>> [ 154.528564] state change PORT_RESET -> SNK_UNATTACHED
>>
>> After:
>> [ 151.068814] pending state change PORT_RESET -> PORT_RESET_WAIT_OFF @ 100 ms [rev3 NONE_AMS]
>> [ 151.072440] CC1: 3 -> 0, CC2: 0 -> 0 [state PORT_RESET, polarity 0, disconnected]
>> [ 151.172117] state change PORT_RESET -> PORT_RESET_WAIT_OFF [delayed 100 ms]
>> [ 151.172136] pending state change PORT_RESET_WAIT_OFF -> SRC_UNATTACHED @ 870 ms [rev3 NONE_AMS]
>> [ 152.060106] state change PORT_RESET_WAIT_OFF -> SRC_UNATTACHED [delayed 870 ms]
>> [ 152.060118] Start toggling
>
> Guenter, can you take a look at this?
>

Sorry, looks like I missed the original patch. Makes sense to me.

Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>

>> Signed-off-by: Badhri Jagan Sridharan <badhri@xxxxxxxxxx>
>> ---
>> drivers/usb/typec/tcpm/tcpm.c | 26 ++++++++++++++++++++++++++
>> 1 file changed, 26 insertions(+)
>>
>> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
>> index de3576e6530ab2..82b19ebd7838e0 100644
>> --- a/drivers/usb/typec/tcpm/tcpm.c
>> +++ b/drivers/usb/typec/tcpm/tcpm.c
>> @@ -3794,6 +3794,14 @@ static void _tcpm_cc_change(struct tcpm_port *port, enum typec_cc_status cc1,
>> */
>> break;
>>
>> + case PORT_RESET:
>> + case PORT_RESET_WAIT_OFF:
>> + /*
>> + * State set back to default mode once the timer completes.
>> + * Ignore CC changes here.
>> + */
>> + break;
>> +
>> default:
>> if (tcpm_port_is_disconnected(port))
>> tcpm_set_state(port, unattached_state(port), 0);
>> @@ -3855,6 +3863,15 @@ static void _tcpm_pd_vbus_on(struct tcpm_port *port)
>> case SRC_TRY_DEBOUNCE:
>> /* Do nothing, waiting for sink detection */
>> break;
>> +
>> + case PORT_RESET:
>> + case PORT_RESET_WAIT_OFF:
>> + /*
>> + * State set back to default mode once the timer completes.
>> + * Ignore vbus changes here.
>> + */
>> + break;
>> +
>> default:
>> break;
>> }
>> @@ -3908,10 +3925,19 @@ static void _tcpm_pd_vbus_off(struct tcpm_port *port)
>> case PORT_RESET_WAIT_OFF:
>> tcpm_set_state(port, tcpm_default_state(port), 0);
>> break;
>> +
>> case SRC_TRY_WAIT:
>> case SRC_TRY_DEBOUNCE:
>> /* Do nothing, waiting for sink detection */
>> break;
>> +
>> + case PORT_RESET:
>> + /*
>> + * State set back to default mode once the timer completes.
>> + * Ignore vbus changes here.
>> + */
>> + break;
>> +
>> default:
>> if (port->pwr_role == TYPEC_SINK &&
>> port->attached)
>> --
>> 2.26.0.292.g33ef6b2f38-goog
>
> thanks,
>