Re: [PATCH v4 7/7] usb: typec: tcpci_rt1711h: Fix CC PHY noise filter of voltage level

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

On Fri, Aug 05, 2022 at 03:17:13PM +0800, Gene Chen wrote:
> From: Gene Chen <gene_chen@richtek.com>
> 
> Fix CC PHY noise filter of voltage level according to
> current cc voltage level
> 
> Signed-off-by: Gene Chen <gene_chen@richtek.com>
> Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>

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

> ---
>  drivers/usb/typec/tcpm/tcpci_rt1711h.c | 58 +++++++++++++++++++++++++++++++++-
>  1 file changed, 57 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/typec/tcpm/tcpci_rt1711h.c b/drivers/usb/typec/tcpm/tcpci_rt1711h.c
> index ff7deae..5dc34f9 100644
> --- a/drivers/usb/typec/tcpm/tcpci_rt1711h.c
> +++ b/drivers/usb/typec/tcpm/tcpci_rt1711h.c
> @@ -24,8 +24,11 @@
>  #define RT1711H_PHYCTRL1	0x80
>  #define RT1711H_PHYCTRL2	0x81
>  
> -#define RT1711H_RTCTRL8		0x9B
> +#define RT1711H_RTCTRL4		0x93
> +/* rx threshold of rd/rp: 1b0 for level 0.4V/0.7V, 1b1 for 0.35V/0.75V */
> +#define RT1711H_BMCIO_RXDZSEL	BIT(0)
>  
> +#define RT1711H_RTCTRL8		0x9B
>  /* Autoidle timeout = (tout * 2 + 1) * 6.4ms */
>  #define RT1711H_RTCTRL8_SET(ck300, ship_off, auto_idle, tout) \
>  			    (((ck300) << 7) | ((ship_off) << 5) | \
> @@ -44,6 +47,10 @@
>  #define RT1711H_RTCTRL15	0xA2
>  #define RT1711H_RTCTRL16	0xA3
>  
> +#define RT1711H_RTCTRL18	0xAF
> +/* 1b0 as fixed rx threshold of rd/rp 0.55V, 1b1 depends on RTCRTL4[0] */
> +#define BMCIO_RXDZEN	BIT(0)
> +
>  struct rt1711h_chip {
>  	struct tcpci_data data;
>  	struct tcpci *tcpci;
> @@ -164,6 +171,53 @@ static int rt1711h_set_vconn(struct tcpci *tcpci, struct tcpci_data *tdata,
>  				  RT1711H_AUTOIDLEEN, enable ? 0 : RT1711H_AUTOIDLEEN);
>  }
>  
> +/*
> + * Selects the CC PHY noise filter voltage level according to the remote current
> + * CC voltage level.
> + *
> + * @status: The port's current cc status read from IC
> + * Return 0 if writes succeed; failure code otherwise
> + */
> +static inline int rt1711h_init_cc_params(struct rt1711h_chip *chip, u8 status)
> +{
> +	int ret, cc1, cc2;
> +	u8 role = 0;
> +	u32 rxdz_en, rxdz_sel;
> +
> +	ret = rt1711h_read8(chip, TCPC_ROLE_CTRL, &role);
> +	if (ret < 0)
> +		return ret;
> +
> +	cc1 = tcpci_to_typec_cc((status >> TCPC_CC_STATUS_CC1_SHIFT) &
> +				TCPC_CC_STATUS_CC1_MASK,
> +				status & TCPC_CC_STATUS_TERM ||
> +				tcpc_presenting_rd(role, CC1));
> +	cc2 = tcpci_to_typec_cc((status >> TCPC_CC_STATUS_CC2_SHIFT) &
> +				TCPC_CC_STATUS_CC2_MASK,
> +				status & TCPC_CC_STATUS_TERM ||
> +				tcpc_presenting_rd(role, CC2));
> +
> +	if ((cc1 >= TYPEC_CC_RP_1_5 && cc2 < TYPEC_CC_RP_DEF) ||
> +	    (cc2 >= TYPEC_CC_RP_1_5 && cc1 < TYPEC_CC_RP_DEF)) {
> +		rxdz_en = BMCIO_RXDZEN;
> +		if (chip->did == RT1715_DID)
> +			rxdz_sel = RT1711H_BMCIO_RXDZSEL;
> +		else
> +			rxdz_sel = 0;
> +	} else {
> +		rxdz_en = 0;
> +		rxdz_sel = RT1711H_BMCIO_RXDZSEL;
> +	}
> +
> +	ret = regmap_update_bits(chip->data.regmap, RT1711H_RTCTRL18,
> +				 BMCIO_RXDZEN, rxdz_en);
> +	if (ret < 0)
> +		return ret;
> +
> +	return regmap_update_bits(chip->data.regmap, RT1711H_RTCTRL4,
> +				  RT1711H_BMCIO_RXDZSEL, rxdz_sel);
> +}
> +
>  static int rt1711h_start_drp_toggling(struct tcpci *tcpci,
>  				      struct tcpci_data *tdata,
>  				      enum typec_cc_status cc)
> @@ -224,6 +278,8 @@ static irqreturn_t rt1711h_irq(int irq, void *dev_id)
>  		/* Clear cc change event triggered by starting toggling */
>  		if (status & TCPC_CC_STATUS_TOGGLING)
>  			rt1711h_write8(chip, TCPC_ALERT, TCPC_ALERT_CC_STATUS);
> +		else
> +			rt1711h_init_cc_params(chip, status);
>  	}
>  
>  out:
> -- 
> 2.7.4
>