Re: [PATCH v4 01/11] net: phy: Add support for microchip SMI0 MDIO bus

[Florian Fainelli <f.fainelli@gmail.com>]

On 8/2/2020 10:44 PM, Michael Grzeschik wrote:
> From: Andrew Lunn <andrew@lunn.ch>
> 
> SMI0 is a mangled version of MDIO. The main low level difference is
> the MDIO C22 OP code is always 0, not 0x2 or 0x1 for Read/Write. The
> read/write information is instead encoded in the PHY address.
> 
> Extend the bit-bang code to allow the op code to be overridden, but
> default to normal C22 values. Add an extra compatible to the mdio-gpio
> driver, and when this compatible is present, set the op codes to 0.
> 
> A higher level driver, sitting on top of the basic MDIO bus driver can
> then implement the rest of the microchip SMI0 odderties.
> 
> Signed-off-by: Andrew Lunn <andrew@lunn.ch>
> Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
> 
> ---

[snip]

> diff --git a/drivers/net/phy/mdio-gpio.c b/drivers/net/phy/mdio-gpio.c
> index 1b00235d7dc5b56..e8d83cee1bc17e1 100644
> --- a/drivers/net/phy/mdio-gpio.c
> +++ b/drivers/net/phy/mdio-gpio.c
> @@ -132,6 +132,14 @@ static struct mii_bus *mdio_gpio_bus_init(struct device *dev,
>  		new_bus->phy_ignore_ta_mask = pdata->phy_ignore_ta_mask;
>  	}
>  
> +	if (dev->of_node &&
> +	    of_device_is_compatible(dev->of_node, "microchip,mdio-smi0")) {
> +		bitbang->ctrl.op_c22_read = 0;
> +		bitbang->ctrl.op_c22_write = 0;
> +	} else {
> +		bitbang->ctrl.override_op_c22 = 1;

Do not you have the logic reversed here? You meant to set
ctrl.override_op_c22 to 1 *if* your compatibility string is
microchip,mdio-smi0 to indicate the use of non-standard clause 22 read
and write opcodes?
-- 
Florian