Re: [PATCH 2/4] usb: typec: ucsi: Register cables based on GET_CABLE_PROPERTY

[Heikki Krogerus <heikki.krogerus@linux.intel.com>]

On Fri, Feb 23, 2024 at 01:03:26AM +0000, Jameson Thies wrote:
> Register cables with the Type-C Connector Class in the UCSI driver based
> on the PPM response to GET_CABLE_PROPERTY. Registered cable properties
> include plug type, cable type and major revision.
> 
> Signed-off-by: Jameson Thies <jthies@google.com>

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

> ---
> Tested on v6.6 kernel. Expected cable properties populate the USB Type-C
> connector class sysfs paths:
> redrix-rev3 /sys/class/typec # ls port2-cable
> device  identity  plug_type  port2-plug0  power  subsystem  type  uevent
> usb_power_delivery_revision
> 
>  drivers/usb/typec/ucsi/ucsi.c | 69 +++++++++++++++++++++++++++++++++++
>  drivers/usb/typec/ucsi/ucsi.h |  5 +++
>  2 files changed, 74 insertions(+)
> 
> diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
> index ae105383e69e..15e82f5fab37 100644
> --- a/drivers/usb/typec/ucsi/ucsi.c
> +++ b/drivers/usb/typec/ucsi/ucsi.c
> @@ -734,6 +734,50 @@ static void ucsi_unregister_partner_pdos(struct ucsi_connector *con)
>  	con->partner_pd = NULL;
>  }
>  
> +static int ucsi_register_cable(struct ucsi_connector *con)
> +{
> +	struct typec_cable *cable;
> +	struct typec_cable_desc desc = {};
> +
> +	switch (UCSI_CABLE_PROP_FLAG_PLUG_TYPE(con->cable_prop.flags)) {
> +	case UCSI_CABLE_PROPERTY_PLUG_TYPE_A:
> +		desc.type = USB_PLUG_TYPE_A;
> +		break;
> +	case UCSI_CABLE_PROPERTY_PLUG_TYPE_B:
> +		desc.type = USB_PLUG_TYPE_B;
> +		break;
> +	case UCSI_CABLE_PROPERTY_PLUG_TYPE_C:
> +		desc.type = USB_PLUG_TYPE_C;
> +		break;
> +	default:
> +		desc.type = USB_PLUG_NONE;
> +		break;
> +	}
> +
> +	desc.active = !!(UCSI_CABLE_PROP_FLAG_ACTIVE_CABLE & con->cable_prop.flags);
> +	desc.pd_revision = UCSI_CABLE_PROP_FLAG_PD_MAJOR_REV_AS_BCD(con->cable_prop.flags);
> +
> +	cable = typec_register_cable(con->port, &desc);
> +	if (IS_ERR(cable)) {
> +		dev_err(con->ucsi->dev,
> +			"con%d: failed to register cable (%ld)\n", con->num,
> +			PTR_ERR(cable));
> +		return PTR_ERR(cable);
> +	}
> +
> +	con->cable = cable;
> +	return 0;
> +}
> +
> +static void ucsi_unregister_cable(struct ucsi_connector *con)
> +{
> +	if (!con->cable)
> +		return;
> +
> +	typec_unregister_cable(con->cable);
> +	con->cable = NULL;
> +}
> +
>  static void ucsi_pwr_opmode_change(struct ucsi_connector *con)
>  {
>  	switch (UCSI_CONSTAT_PWR_OPMODE(con->status.flags)) {
> @@ -807,6 +851,7 @@ static void ucsi_unregister_partner(struct ucsi_connector *con)
>  	typec_partner_set_usb_power_delivery(con->partner, NULL);
>  	ucsi_unregister_partner_pdos(con);
>  	ucsi_unregister_altmodes(con, UCSI_RECIPIENT_SOP);
> +	ucsi_unregister_cable(con);
>  	typec_unregister_partner(con->partner);
>  	con->partner = NULL;
>  }
> @@ -907,6 +952,28 @@ static int ucsi_check_connection(struct ucsi_connector *con)
>  	return 0;
>  }
>  
> +static int ucsi_check_cable(struct ucsi_connector *con)
> +{
> +	u64 command;
> +	int ret;
> +
> +	if (con->cable)
> +		return 0;
> +
> +	command = UCSI_GET_CABLE_PROPERTY | UCSI_CONNECTOR_NUMBER(con->num);
> +	ret = ucsi_send_command(con->ucsi, command, &con->cable_prop, sizeof(con->cable_prop));
> +	if (ret < 0) {
> +		dev_err(con->ucsi->dev, "GET_CABLE_PROPERTY failed (%d)\n", ret);
> +		return ret;
> +	}
> +
> +	ret = ucsi_register_cable(con);
> +	if (ret < 0)
> +		return ret;
> +
> +	return 0;
> +}
> +
>  static void ucsi_handle_connector_change(struct work_struct *work)
>  {
>  	struct ucsi_connector *con = container_of(work, struct ucsi_connector,
> @@ -948,6 +1015,7 @@ static void ucsi_handle_connector_change(struct work_struct *work)
>  			ucsi_register_partner(con);
>  			ucsi_partner_task(con, ucsi_check_connection, 1, HZ);
>  			ucsi_partner_task(con, ucsi_check_connector_capability, 1, HZ);
> +			ucsi_partner_task(con, ucsi_check_cable, 1, HZ);
>  
>  			if (UCSI_CONSTAT_PWR_OPMODE(con->status.flags) ==
>  			    UCSI_CONSTAT_PWR_OPMODE_PD)
> @@ -1346,6 +1414,7 @@ static int ucsi_register_port(struct ucsi *ucsi, struct ucsi_connector *con)
>  		ucsi_register_partner(con);
>  		ucsi_pwr_opmode_change(con);
>  		ucsi_port_psy_changed(con);
> +		ucsi_check_cable(con);
>  	}
>  
>  	/* Only notify USB controller if partner supports USB data */
> diff --git a/drivers/usb/typec/ucsi/ucsi.h b/drivers/usb/typec/ucsi/ucsi.h
> index 469a2baf472e..f0aabef0b7c6 100644
> --- a/drivers/usb/typec/ucsi/ucsi.h
> +++ b/drivers/usb/typec/ucsi/ucsi.h
> @@ -265,6 +265,9 @@ struct ucsi_cable_property {
>  #define   UCSI_CABLE_PROPERTY_PLUG_TYPE_C	2
>  #define   UCSI_CABLE_PROPERTY_PLUG_OTHER	3
>  #define UCSI_CABLE_PROP_FLAG_MODE_SUPPORT	BIT(5)
> +#define UCSI_CABLE_PROP_FLAG_PD_MAJOR_REV(_f_)	(((_f_) & GENMASK(7, 6)) >> 6)
> +#define UCSI_CABLE_PROP_FLAG_PD_MAJOR_REV_AS_BCD(_f_) \
> +	UCSI_SPEC_REVISION_TO_BCD(UCSI_CABLE_PROP_FLAG_PD_MAJOR_REV(_f_))
>  	u8 latency;
>  } __packed;
>  
> @@ -400,6 +403,7 @@ struct ucsi_connector {
>  
>  	struct typec_port *port;
>  	struct typec_partner *partner;
> +	struct typec_cable *cable;
>  
>  	struct typec_altmode *port_altmode[UCSI_MAX_ALTMODES];
>  	struct typec_altmode *partner_altmode[UCSI_MAX_ALTMODES];
> @@ -408,6 +412,7 @@ struct ucsi_connector {
>  
>  	struct ucsi_connector_status status;
>  	struct ucsi_connector_capability cap;
> +	struct ucsi_cable_property cable_prop;
>  	struct power_supply *psy;
>  	struct power_supply_desc psy_desc;
>  	u32 rdo;
> -- 
> 2.44.0.rc0.258.g7320e95886-goog

-- 
heikki