On 6/7/22 3:37 AM, Damien Le Moal wrote:
[...]
>>>> The {dma|pio|xfer}_mode sysfs files are incorrectly handled by the
>>>> ata_bitfield_name_match() macro which leads to reading such kind of
>>>> nonsense from them:
>>>>
>>>> $ cat /sys/class/ata_device/dev3.0/pio_mode
>>>> XFER_UDMA_7, XFER_UDMA_6, XFER_UDMA_5, XFER_UDMA_4, XFER_MW_DMA_4,
>>>> XFER_PIO_6, XFER_PIO_5, XFER_PIO_4, XFER_PIO_3, XFER_PIO_2, XFER_PIO_1,
>>>> XFER_PIO_0
>>>>
>>>> Using the correct ata_bitfield_name_search() macro fixes that:
>>>>
>>>> $ cat /sys/class/ata_device/dev3.0/pio_mode
>>>> XFER_PIO_4
>>>
>>> Looks good, but Documentation/ABI/testing/sysfs-ata says:
>>
>> Completely forgot that the sysfs files are documented as ABIs... :-(
>> Hm, shouldn't that file be added to the libata's entry in MAINTAINERS?
So what's your opinion on that idea?
>>> pio_mode: (RO) Transfer modes supported by the device when
>>> in PIO mode. Mostly used by PATA device.
>>>
>>> xfer_mode: (RO) Current transfer mode
>>>
>>> dma_mode: (RO) Transfer modes supported by the device when
>>> in DMA mode. Mostly used by PATA device.
>>>
>>> which seems incorrect/badly worded for pio_mode and dma_mode. Since these
>>> 2 sysfs attributes do not actually device the pio mask (list of supported
>>
>> Device?
>
> advertise :)
Makes sense now. :-)
>>> pio modes) but the pio mode that will be used for that device, we should
>>> reword, no ?
>>
>> Yes, of course. :-)
>>
>>> What about:
>>>
>>> pio_mode: (RO) Transfer mode used by the device when
>>> in PIO mode. Mostly used by PATA device.
>>>
>>> xfer_mode: (RO) Current transfer mode
>>>
>>> dma_mode: (RO) Transfer mode used by the device when
>>> in DMA mode. Mostly used by PATA device.
>>
>> Sounds quite tautological... :-)
>> What about:
>>
>> {dma|pio}_mode: (RO) {DMA|PIO} transfer mode used by the device.
>> Mostly used by PATA devices.
>>
>> I think this should be done in the same patch. Or would you prefer 2 patches?
>
> Let's do 2 patches. Not sure if you can find a fixes tag for the doc update
It'll be the same tag.
> though. But we should not aggregate the 2 attributes as you did. These doc files
> have a defined format and may not be happy with that merged syntax.
Sorry about that -- I did that just for the mail... :-)
MBR, Sergey
