Re: [RFC PATCH net-next 5/8] net: phy: realtek: use phy_read_paged instead of open coding

From: Heiner Kallweit
Date: Sat Apr 22 2023 - 11:12:06 EST


On 22.04.2023 13:48, Daniel Golle wrote:
> Instead of open coding a paged read, use the phy_read_paged function
> in rtlgen_supports_2_5gbps.
>
> Signed-off-by: Daniel Golle <daniel@xxxxxxxxxxxxxx>
> ---
> drivers/net/phy/realtek.c | 4 +---
> 1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/drivers/net/phy/realtek.c b/drivers/net/phy/realtek.c
> index f97b5e49fae58..62fb965b6d338 100644
> --- a/drivers/net/phy/realtek.c
> +++ b/drivers/net/phy/realtek.c
> @@ -735,9 +735,7 @@ static bool rtlgen_supports_2_5gbps(struct phy_device *phydev)
> {
> int val;
>
> - phy_write(phydev, RTL821x_PAGE_SELECT, 0xa61);
> - val = phy_read(phydev, 0x13);
> - phy_write(phydev, RTL821x_PAGE_SELECT, 0);
> + val = phy_read_paged(phydev, 0xa61, 0x13);
>
> return val >= 0 && val & RTL_SUPPORTS_2500FULL;
> }

I remember I had a reason to open-code it, it took me some minutes
to recall it.
phy_read_paged() calls __phy_read_page() that relies on phydev->drv
being set. phydev->drv is set in phy_probe(). And probing is done
after matching. __phy_read_paged() should have given you a warning.
Did you test this patch? If yes and you didn't get the warning,
then apparently I miss something.