[PATCH] net: ravb: Fix NULL pointer access

[Marek Vasut <marek.vasut@gmail.com>]

On 9/19/20 1:14 PM, Biju Das wrote:
[...]
>>> By looking at [1], only this driver is using writeext.
>>> [1]https://elixir.bootlin.com/u-boot/v2020.10-rc4/A/ident/writeext
>>
>> git grep indicates a couple more sites where the writeext is called.
>> But look into the KSZ9031 datasheet, that particular writeext call seems to be
>> setting up RGMII Clock Pad Skew (MMD Address 2, Register 8), and I think
>> there is a matching DT binding to set those up too, rxc-skew-ps and txc-
>> skew-ps I think.
> 
> Thanks for the pointers.  I checked the configs[2] which uses renesas ravb driver
> and found that we are defining only rxc-skew-ps in all dts.
> 
> since CONFIG DM_ETH is defined it is already picking the value corresponding to "rxc-skew-ps".
> 
> For txc-skew-ps anyway the value is default one. So we don't care.

Are you sure (0xf << 5) | 0x19 is the same as the default value of the
clock pad skew register ?

[...]