Re: [PATCH v2 2/4] net: phy: dp83867: add support for MAC impedance configuration

[Lokesh Vutla]

On Tuesday 04 October 2016 06:26 PM, Mugunthan V N wrote:
> Add support for programmable MAC impedance configuration
> 
> Signed-off-by: Mugunthan V N <mugunthanvnm@xxxxxx>
> ---
>  drivers/net/phy/dp83867.c | 28 ++++++++++++++++++++++++++++
>  1 file changed, 28 insertions(+)
> 
> diff --git a/drivers/net/phy/dp83867.c b/drivers/net/phy/dp83867.c
> index 91177a4..795ae17 100644
> --- a/drivers/net/phy/dp83867.c
> +++ b/drivers/net/phy/dp83867.c
> @@ -33,6 +33,7 @@
>  /* Extended Registers */
>  #define DP83867_RGMIICTL	0x0032
>  #define DP83867_RGMIIDCTL	0x0086
> +#define DP83867_IO_MUX_CFG	0x0170
>  
>  #define DP83867_SW_RESET	BIT(15)
>  #define DP83867_SW_RESTART	BIT(14)
> @@ -62,10 +63,17 @@
>  /* RGMIIDCTL bits */
>  #define DP83867_RGMII_TX_CLK_DELAY_SHIFT	4
>  
> +/* IO_MUX_CFG bits */
> +#define DP83867_IO_MUX_CFG_IO_IMPEDANCE_CTRL	0x1f
> +
> +#define DP83867_IO_MUX_CFG_IO_IMPEDANCE_MAX	0x0
> +#define DP83867_IO_MUX_CFG_IO_IMPEDANCE_MIN	0x1f
> +
>  struct dp83867_private {
>  	int rx_id_delay;
>  	int tx_id_delay;
>  	int fifo_depth;
> +	int io_impedance;
>  };
>  
>  static int dp83867_ack_interrupt(struct phy_device *phydev)
> @@ -111,6 +119,14 @@ static int dp83867_of_init(struct phy_device *phydev)
>  	if (!of_node)
>  		return -ENODEV;
>  
> +	dp83867->io_impedance = -EINVAL;
> +
> +	/* Optional configuration */
> +	if (of_property_read_bool(of_node, "ti,max-output-imepdance"))

s/imepdance/impedance

> +		dp83867->io_impedance = DP83867_IO_MUX_CFG_IO_IMPEDANCE_MAX;
> +	else if (of_property_read_bool(of_node, "ti,min-output-imepdance"))

s/imepdance/impedance

Thanks and regards,
Lokesh

> +		dp83867->io_impedance = DP83867_IO_MUX_CFG_IO_IMPEDANCE_MIN;
> +
>  	ret = of_property_read_u32(of_node, "ti,rx-internal-delay",
>  				   &dp83867->rx_id_delay);
>  	if (ret)
> @@ -184,6 +200,18 @@ static int dp83867_config_init(struct phy_device *phydev)
>  
>  		phy_write_mmd_indirect(phydev, DP83867_RGMIIDCTL,
>  				       DP83867_DEVADDR, delay);
> +
> +		if (dp83867->io_impedance >= 0) {
> +			val = phy_read_mmd_indirect(phydev, DP83867_IO_MUX_CFG,
> +						    DP83867_DEVADDR);
> +
> +			val &= ~DP83867_IO_MUX_CFG_IO_IMPEDANCE_CTRL;
> +			val |= dp83867->io_impedance &
> +			       DP83867_IO_MUX_CFG_IO_IMPEDANCE_CTRL;
> +
> +			phy_write_mmd_indirect(phydev, DP83867_IO_MUX_CFG,
> +					       DP83867_DEVADDR, val);
> +		}
>  	}
>  
>  	return 0;
>