> Some embedded board designs use GPIO-controlled regulators for the
> DP83867 power rails. Add dp83867_power_on() to enable all four supply
> domains at probe time. Absent supplies are silently skipped, so boards
> that do not describe them are unaffected.
> 
> When any supply is newly enabled the driver sleeps for 200 ms before
> returning.  This satisfies the post power-up stabilisation requirement
> mentioned in section 6.6 of the DP83867E/IS/CS datasheet.
> 
> Signed-off-by: Mohd Ayaan Anwar <mohd.anwar@oss.qualcomm.com>

Acked-by: Lorenzo Bianconi <lorenzo.bianconi@oss.qualcomm.com>

> ---
>  drivers/net/phy/dp83867.c | 33 +++++++++++++++++++++++++++++++++
>  1 file changed, 33 insertions(+)
> 
> diff --git a/drivers/net/phy/dp83867.c b/drivers/net/phy/dp83867.c
> index 88255e92b4cdbd6da2e2c1d10f9c72348d28dbc3..dbeee7cad6f0cbfeb127bfd28f43ee2a16c78879 100644
> --- a/drivers/net/phy/dp83867.c
> +++ b/drivers/net/phy/dp83867.c
> @@ -15,6 +15,7 @@
>  #include <linux/etherdevice.h>
>  #include <linux/bitfield.h>
>  #include <linux/nvmem-consumer.h>
> +#include <linux/regulator/consumer.h>
>  
>  #include <dt-bindings/net/ti-dp83867.h>
>  
> @@ -719,9 +720,41 @@ static int dp83867_resume(struct phy_device *phydev)
>  	return 0;
>  }
>  
> +static int dp83867_power_on(struct phy_device *phydev)
> +{
> +#ifdef CONFIG_OF
> +	static const char * const supply_names[] = {
> +		"vdda-2p5", "vdd-1p0", "vdda-1p8", "vddio",
> +	};
> +	struct device *dev = &phydev->mdio.dev;
> +	u32 count = 0;
> +	int i, ret;
> +
> +	for (i = 0; i < ARRAY_SIZE(supply_names); i++) {
> +		ret = devm_regulator_get_enable_optional(dev, supply_names[i]);

nit: I guess it easier to read if you do something like:

		if (ret != -ENODEV)
			return dev_err_probe();

		count += !ret;

> +		if (!ret)
> +			count++;
> +		else if (ret != -ENODEV)
> +			return dev_err_probe(dev, ret,
> +					     "failed to enable %s supply\n",
> +					     supply_names[i]);
> +	}
> +
> +	/* Datasheet section 6.6 suggests a 200ms post power-up stabilization */
> +	if (count)
> +		fsleep(200000);
> +#endif
> +	return 0;
> +}
> +
>  static int dp83867_probe(struct phy_device *phydev)
>  {
>  	struct dp83867_private *dp83867;
> +	int ret;
> +
> +	ret = dp83867_power_on(phydev);
> +	if (ret)
> +		return ret;
>  
>  	dp83867 = devm_kzalloc(&phydev->mdio.dev, sizeof(*dp83867),
>  			       GFP_KERNEL);
> 
> -- 
> 2.34.1
> 
>