Hi Wolfram,
> If the controller can only do 4 byte reads, this needs to be applied for the
> read-part of combined messages, too.
>
> Signed-off-by: Wolfram Sang <wsa@xxxxxxxxxxxxx>
> ---
>
> An educated guess from the supplied information. Needs to be confirmed.
Yes, it is needed as per logic in drivers/i2c/i2c-core-base.c.
I tested the patch and can see i2c subsystem showing below error if second
Message is of more than 4 byte length.
"i2c i2c-4: adapter quirk: msg too long (addr 0x0008, size 16, read)"
There was no such error without this patch.
Acked-by: Ajay Gupta <ajayg@xxxxxxxxxx>
Tested-by: Ajay Gupta <ajayg@xxxxxxxxxx>
Thanks
Ajay
> nvpublic
>
> drivers/i2c/busses/i2c-nvidia-gpu.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/i2c/busses/i2c-nvidia-gpu.c b/drivers/i2c/busses/i2c-nvidia-
> gpu.c
> index 4307b42901a1..e99c3bb58351 100644
> --- a/drivers/i2c/busses/i2c-nvidia-gpu.c
> +++ b/drivers/i2c/busses/i2c-nvidia-gpu.c
> @@ -218,6 +218,7 @@ static int gpu_i2c_master_xfer(struct i2c_adapter
> *adap,
>
> static const struct i2c_adapter_quirks gpu_i2c_quirks = {
> .max_read_len = 4,
> + .max_comb_2nd_msg_len = 4,
> .flags = I2C_AQ_COMB_WRITE_THEN_READ,
> };
I
>
> --
> 2.19.1
