Re: [PATCH v2 3/7] phy: phy-mtk-tphy: add property to set pre-emphasis

[AngeloGioacchino Del Regno]

Il 29/08/22 10:08, Chunfeng Yun ha scritto:
> Add a property to set usb2 phy's pre-emphasis, it's disabled by default
> on some SoCs.
>
> Signed-off-by: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx>
> ---
> v2: no changes
> ---
>   drivers/phy/mediatek/phy-mtk-tphy.c | 10 ++++++++++
>   1 file changed, 10 insertions(+)
>
> diff --git a/drivers/phy/mediatek/phy-mtk-tphy.c b/drivers/phy/mediatek/phy-mtk-tphy.c
> index 8ee7682b8e93..986fde0f63a0 100644
> --- a/drivers/phy/mediatek/phy-mtk-tphy.c
> +++ b/drivers/phy/mediatek/phy-mtk-tphy.c
> @@ -72,6 +72,8 @@
>   #define PA5_RG_U2_HS_100U_U3_EN	BIT(11)
>   
>   #define U3P_USBPHYACR6		0x018
> +#define PA6_RG_U2_PRE_EMP		GENMASK(31, 30)
> +#define PA6_RG_U2_PRE_EMP_VAL(x)	((0x3 & (x)) << 30)

Hello Chunfeng,

can you please clarify which SoC is this change referred to?

If I'm not missing anything, there may be a register layout conflict between
one version and the other for T-PHYs, for which, it may be a good idea to add
a PHY version check before allowing to write settings that are supported only
on a specific IP...

Regards,
Angelo