Re: [PATCH v2 07/11] usb: typec: ucsi: support delaying GET_PDOS for device

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

On Fri, Mar 29, 2024 at 08:15:39AM +0200, Dmitry Baryshkov wrote:
> Qualcomm firmware doesn't return sane information for device's PDOs
> unless the partner is also using a PD mode. On SC8280XP this even
> results in the Error bit being set in the UCSI response (with 0 error
> status).
> 
> Add a quirk to delay reading USB PD capabilities for a device until we
> detect a partner in PD mode.
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

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

> ---
>  drivers/usb/typec/ucsi/ucsi.c | 41 ++++++++++++++++++++++++++++-------------
>  drivers/usb/typec/ucsi/ucsi.h |  1 +
>  2 files changed, 29 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
> index 18b2e4ffc57e..f5ec776b84d6 100644
> --- a/drivers/usb/typec/ucsi/ucsi.c
> +++ b/drivers/usb/typec/ucsi/ucsi.c
> @@ -821,6 +821,28 @@ static int ucsi_check_altmodes(struct ucsi_connector *con)
>  	return ret;
>  }
>  
> +static void ucsi_register_device_pdos(struct ucsi_connector *con)
> +{
> +	struct ucsi *ucsi = con->ucsi;
> +	struct usb_power_delivery_desc desc = { ucsi->cap.pd_version };
> +	struct usb_power_delivery_capabilities *pd_cap;
> +
> +	if (con->pd)
> +		return;
> +
> +	con->pd = usb_power_delivery_register(ucsi->dev, &desc);
> +
> +	pd_cap = ucsi_get_pd_caps(con, TYPEC_SOURCE, false);
> +	if (!IS_ERR(pd_cap))
> +		con->port_source_caps = pd_cap;
> +
> +	pd_cap = ucsi_get_pd_caps(con, TYPEC_SINK, false);
> +	if (!IS_ERR(pd_cap))
> +		con->port_sink_caps = pd_cap;
> +
> +	typec_port_set_usb_power_delivery(con->port, con->pd);
> +}
> +
>  static int ucsi_register_partner_pdos(struct ucsi_connector *con)
>  {
>  	struct usb_power_delivery_desc desc = { con->ucsi->cap.pd_version };
> @@ -981,6 +1003,9 @@ static int ucsi_register_partner(struct ucsi_connector *con)
>  		break;
>  	}
>  
> +	if (pwr_opmode == UCSI_CONSTAT_PWR_OPMODE_PD)
> +		ucsi_register_device_pdos(con);
> +
>  	desc.identity = &con->partner_identity;
>  	desc.usb_pd = pwr_opmode == UCSI_CONSTAT_PWR_OPMODE_PD;
>  	desc.pd_revision = UCSI_CONCAP_FLAG_PARTNER_PD_MAJOR_REV_AS_BCD(con->cap.flags);
> @@ -1465,8 +1490,6 @@ static struct fwnode_handle *ucsi_find_fwnode(struct ucsi_connector *con)
>  
>  static int ucsi_register_port(struct ucsi *ucsi, struct ucsi_connector *con)
>  {
> -	struct usb_power_delivery_desc desc = { ucsi->cap.pd_version};
> -	struct usb_power_delivery_capabilities *pd_cap;
>  	struct typec_capability *cap = &con->typec_cap;
>  	enum typec_accessory *accessory = cap->accessory;
>  	enum usb_role u_role = USB_ROLE_NONE;
> @@ -1544,17 +1567,8 @@ static int ucsi_register_port(struct ucsi *ucsi, struct ucsi_connector *con)
>  		goto out;
>  	}
>  
> -	con->pd = usb_power_delivery_register(ucsi->dev, &desc);
> -
> -	pd_cap = ucsi_get_pd_caps(con, TYPEC_SOURCE, false);
> -	if (!IS_ERR(pd_cap))
> -		con->port_source_caps = pd_cap;
> -
> -	pd_cap = ucsi_get_pd_caps(con, TYPEC_SINK, false);
> -	if (!IS_ERR(pd_cap))
> -		con->port_sink_caps = pd_cap;
> -
> -	typec_port_set_usb_power_delivery(con->port, con->pd);
> +	if (!(ucsi->quirks & UCSI_DELAY_DEVICE_PDOS))
> +		ucsi_register_device_pdos(con);
>  
>  	/* Alternate modes */
>  	ret = ucsi_register_altmodes(con, UCSI_RECIPIENT_CON);
> @@ -1617,6 +1631,7 @@ static int ucsi_register_port(struct ucsi *ucsi, struct ucsi_connector *con)
>  	if (con->partner &&
>  	    UCSI_CONSTAT_PWR_OPMODE(con->status.flags) ==
>  	    UCSI_CONSTAT_PWR_OPMODE_PD) {
> +		ucsi_register_device_pdos(con);
>  		ucsi_get_src_pdos(con);
>  		ucsi_check_altmodes(con);
>  	}
> diff --git a/drivers/usb/typec/ucsi/ucsi.h b/drivers/usb/typec/ucsi/ucsi.h
> index 591f734d457b..2caf2969668c 100644
> --- a/drivers/usb/typec/ucsi/ucsi.h
> +++ b/drivers/usb/typec/ucsi/ucsi.h
> @@ -406,6 +406,7 @@ struct ucsi {
>  
>  	unsigned long quirks;
>  #define UCSI_NO_PARTNER_PDOS	BIT(0)	/* Don't read partner's PDOs */
> +#define UCSI_DELAY_DEVICE_PDOS	BIT(1)	/* Reading PDOs fails until the parter is in PD mode */
>  };
>  
>  #define UCSI_MAX_SVID		5
> 
> -- 
> 2.39.2

-- 
heikki