Re: [PATCH v2 3/3] usb: typec: tcpci_maxim: Enable VSAFE0V signalling

[Guenter Roeck <linux@roeck-us.net>]

On Tue, Dec 01, 2020 at 08:08:40PM -0800, Badhri Jagan Sridharan wrote:
> Unmask EXTENDED_STATUS_MASK.vSafe0V, ALERT.Extended_Status
> and set vbus_vsafe0v to enable VSAFE0V signalling.
> 
> Signed-off-by: Badhri Jagan Sridharan <badhri@google.com>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> ---
> Changes since v1:
> - Setting auto_discharge_disconnect to true instead of 1 as
>   suggested by Guenter.
> ---
>  drivers/usb/typec/tcpm/tcpci_maxim.c | 16 +++++++++++++++-
>  1 file changed, 15 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/typec/tcpm/tcpci_maxim.c b/drivers/usb/typec/tcpm/tcpci_maxim.c
> index c1797239bf08..319266329b42 100644
> --- a/drivers/usb/typec/tcpm/tcpci_maxim.c
> +++ b/drivers/usb/typec/tcpm/tcpci_maxim.c
> @@ -112,11 +112,18 @@ static void max_tcpci_init_regs(struct max_tcpci_chip *chip)
>  		return;
>  	}
>  
> +	/* Enable VSAFE0V detection */
> +	ret = max_tcpci_write8(chip, TCPC_EXTENDED_STATUS_MASK, TCPC_EXTENDED_STATUS_VSAFE0V);
> +	if (ret < 0) {
> +		dev_err(chip->dev, "Unable to unmask TCPC_EXTENDED_STATUS_VSAFE0V ret:%d\n", ret);
> +		return;
> +	}
> +
>  	alert_mask = TCPC_ALERT_TX_SUCCESS | TCPC_ALERT_TX_DISCARDED | TCPC_ALERT_TX_FAILED |
>  		TCPC_ALERT_RX_HARD_RST | TCPC_ALERT_RX_STATUS | TCPC_ALERT_CC_STATUS |
>  		TCPC_ALERT_VBUS_DISCNCT | TCPC_ALERT_RX_BUF_OVF | TCPC_ALERT_POWER_STATUS |
>  		/* Enable Extended alert for detecting Fast Role Swap Signal */
> -		TCPC_ALERT_EXTND;
> +		TCPC_ALERT_EXTND | TCPC_ALERT_EXTENDED_STATUS;
>  
>  	ret = max_tcpci_write16(chip, TCPC_ALERT_MASK, alert_mask);
>  	if (ret < 0) {
> @@ -315,6 +322,12 @@ static irqreturn_t _max_tcpci_irq(struct max_tcpci_chip *chip, u16 status)
>  		}
>  	}
>  
> +	if (status & TCPC_ALERT_EXTENDED_STATUS) {
> +		ret = max_tcpci_read8(chip, TCPC_EXTENDED_STATUS, (u8 *)&reg_status);
> +		if (ret >= 0 && (reg_status & TCPC_EXTENDED_STATUS_VSAFE0V))
> +			tcpm_vbus_change(chip->port);
> +	}
> +
>  	if (status & TCPC_ALERT_RX_STATUS)
>  		process_rx(chip, status);
>  
> @@ -442,6 +455,7 @@ static int max_tcpci_probe(struct i2c_client *client, const struct i2c_device_id
>  	chip->data.init = tcpci_init;
>  	chip->data.frs_sourcing_vbus = max_tcpci_frs_sourcing_vbus;
>  	chip->data.auto_discharge_disconnect = true;
> +	chip->data.vbus_vsafe0v = true;
>  
>  	max_tcpci_init_regs(chip);
>  	chip->tcpci = tcpci_register_port(chip->dev, &chip->data);
> -- 
> 2.29.2.576.ga3fc446d84-goog
>