[PATCH] mtd: spi-nor: handle unsupported FSR opcodes properly

[Michael Walle]

Am 15. Juni 2022 11:49:22 OEZ schrieb Mika Westerberg <mika.westerberg at linux.intel.com>:
>Hi,
>
>On Tue, Jun 14, 2022 at 05:56:54PM +0000, Oleksandr Ocheretnyi -X (oocheret - GLOBALLOGIC INC at Cisco) wrote:
>>    Hello Mika,
>> 
>>    in my case (I work with memory chip n25q128a13 for recent kernels) I'm
>>    getting return value -ENOTSUPP from spi_mem_exec_op() call in the
>>    micron_st_nor_read_fsr() method
>>    [[1]https://elixir.bootlin.com/linux/v5.19-rc2/source/drivers/spi/spi-m
>>    em.c#L326]. So I decided to provide the same errorcode to
>>    intel_spi_hw_cycle() method because older kernel versions throw the
>>    error there. It is fine to use -EOPNOTSUPP return value instead.
>> 
>>    I suspect we need to cover both cases to check -ENOTSUPP as well as
>>    -EOPNOTSUPP to let the driver work properly.
>> 
>>    if (ret == -ENOTSUPP || ret == -EOPNOTSUPP)
>
>I think we should follow the same in the Intel driver and return
>-ENOTSUPP too.

AFAIK ENOTSUPP is for nfs and shouldn't be used.

-michael