[PATCH] phy: rockchip: inno-usb2: fix phy reg=0 case

[Kever Yang]

On 2023/5/22 16:39, Eugen Hristev wrote:
> The support for #address-cells=2 has a loophole: if the reg is actually 0,
> but the #address-cells is actually 1, like in such case below:
>
> syscon {
> 	#address-cells = <1>;
>
> 	phy {
> 		reg = <0 0x10>;
> 	};
> };
>
> then the second u32 of the 'reg' is the size, not the address.
>
> The code should check for the parent's #address-cells value, and not
> assume that if the first u32 is 0, then the #address-cells is 2, and the
> reg property is something like
> 	reg = <0 0xff00 0x10>;
>
> Fixed this by looking for the #address-cells value and retrieving the
> reg address only if this is ==2.
> To avoid breaking anything I also kept the check `if reg==0` as some DT's
> may have a wrong #address-cells as parent and even if this commit is
> correct, it might break the existing wrong device-trees.
>
> Fixes: d538efb9adcf ("phy: rockchip: inno-usb2: Add support #address_cells = 2")
> Signed-off-by: Eugen Hristev <eugen.hristev at collabora.com>


Reviewed-by: Kever Yang <kever.yang at rock-chips.com>

Thanks,
- Kever

> ---
>   drivers/phy/rockchip/phy-rockchip-inno-usb2.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/phy/rockchip/phy-rockchip-inno-usb2.c b/drivers/phy/rockchip/phy-rockchip-inno-usb2.c
> index 22e2797eea28..e5e02b6765b1 100644
> --- a/drivers/phy/rockchip/phy-rockchip-inno-usb2.c
> +++ b/drivers/phy/rockchip/phy-rockchip-inno-usb2.c
> @@ -186,7 +186,7 @@ static int rockchip_usb2phy_probe(struct udevice *dev)
>   	}
>   
>   	/* support address_cells=2 */
> -	if (reg == 0) {
> +	if (dev_read_addr_cells(dev) == 2 && reg == 0) {
>   		if (ofnode_read_u32_index(dev_ofnode(dev), "reg", 1, &reg)) {
>   			dev_err(dev, "%s must have reg[1]\n",
>   				ofnode_get_name(dev_ofnode(dev)));