[PATCH] i2c: sandbox: Avoid calling dev_read_*() if CONFIG_OF_PLATDATA=y

[Marek Vasut]

On 11/20/25 10:08 AM, Heiko Schocher wrote:

Hello Heiko,

>> diff --git a/drivers/i2c/i2c-uclass.c b/drivers/i2c/i2c-uclass.c
>> index 380a9f8f3ad..d0e9dad7202 100644
>> --- a/drivers/i2c/i2c-uclass.c
>> +++ b/drivers/i2c/i2c-uclass.c
>> @@ -749,8 +749,11 @@ static int i2c_post_probe(struct udevice *dev)
>>   #if CONFIG_IS_ENABLED(OF_REAL)
>>       struct dm_i2c_bus *i2c = dev_get_uclass_priv(dev);
>> -    i2c->speed_hz = dev_read_u32_default(dev, "clock-frequency",
>> -                         I2C_SPEED_STANDARD_RATE);
>> +    if (!dev_has_ofnode(dev))
>> +        i2c->speed_hz = I2C_SPEED_STANDARD_RATE;
>> +    else
>> +        i2c->speed_hz = dev_read_u32_default(dev, "clock-frequency",
>> +                             I2C_SPEED_STANDARD_RATE);
>>       return dm_i2c_set_bus_speed(dev, i2c->speed_hz);
>>   #else
>>
> 
> This sounds more as a bug of dev_read_u32_default() to me and should
> be fixed there, else we need to make this check around each call of
> dev_read_u32_default() ...
> 
> And looking into u-boot:/drivers/core/read.c there are more
> candidates for such a fix (all with "default" in function name?)
> 
> and such a fix would also make the dev_has_ofnode(dev) check in
> i2c_child_post_bind() obsolete.
> 
> Or may we fix the default functions in drivers/core/ofnode.c ?
No, this was the previous implementation which is now superseded by this 
one, see [1] [2]. The goal is to fix the entry points which pass invalid 
content further into U-Boot DT handling code, so the DT validation 
happens only one, on DT input, and not again later.

Also, please wait for feedback on [3] [4] [5] [6] before possibly 
applying this one.

[1] 
https://lore.kernel.org/u-boot/20251113122145.949112-2-marek.vasut+renesas@mailbox.org/
[2] 
https://lore.kernel.org/u-boot/20251113122145.949112-4-marek.vasut+renesas@mailbox.org/

[3] 
https://lore.kernel.org/u-boot/20251120041439.817233-1-marek.vasut+renesas@mailbox.org/
[4] 
https://lore.kernel.org/u-boot/20251120041504.817264-1-marek.vasut+renesas@mailbox.org/
[5] 
https://lore.kernel.org/u-boot/20251120041526.817288-1-marek.vasut+renesas@mailbox.org/
[6] 
https://lore.kernel.org/u-boot/20251120041613.817311-1-marek.vasut+renesas@mailbox.org/