On 3/15/21 9:21 PM, Chris Packham wrote:
>
> On 16/03/21 4:43 pm, Guenter Roeck wrote:
>> On 3/15/21 7:35 PM, Chris Packham wrote:
>>> The BPA-RS600 is a compact 600W AC to DC removable power supply module.
>>>
>>> Signed-off-by: Chris Packham <chris.pack...@alliedtelesis.co.nz>
>>> ---
> <snip>
>>> +
>>> +static int bpa_rs600_read_word_data(struct i2c_client *client, int page,
>>> + int phase, int reg)+{
>>> + int ret;
>>> +
>>> + if (page > 0)
>>> + return -ENXIO;
>>> +
>>> + switch (reg) {
>>> + case PMBUS_VIN_UV_FAULT_LIMIT:
>>> + case PMBUS_VIN_OV_FAULT_LIMIT:
>>> + case PMBUS_VOUT_UV_FAULT_LIMIT:
>>> + case PMBUS_VOUT_OV_FAULT_LIMIT:
>>> + ret = -ENXIO;
>> Is that needed ? Why not -ENODATA ?
>
> Basically these commands get responses on the bus but they don't have
> valid data (nor are they documented in the datasheet). I'll add a
> comment to that effect.
>
> If I'm reading things correctly -ENODATA is a signal to
> _pmbus_read_word_data use the "normal" read operation. So I need to
Correct.
> return something other than that. I found another driver (mp2975.c)
> doing the same thing for what I assume are similar reasons so I went
> with -ENXIO.
>
-ENXIO is ok, but please document it.
Thanks,
Guenter
