Re: [PATCH 62/86] pata_pdc202xx_old: document known issues

Jeff Garzik
2009-11-25T18:04:19Z

On 11/25/2009 12:52 PM, Bartlomiej Zolnierkiewicz wrote:
> On Wednesday 25 November 2009 06:50:26 pm Jeff Garzik wrote:
>> On 11/25/2009 12:46 PM, Alan Cox wrote:
>>> On Wed, 25 Nov 2009 18:09:48 +0100
>>> Bartlomiej Zolnierkiewicz<bzolnier@gmail.com> wrote:
>>>
>>>> From: Bartlomiej Zolnierkiewicz<bzolnier@gmail.com>
>>>> Subject: [PATCH] pata_pdc202xx_old: document known issues
>>>>
>>>> Document known issues with the driver to aid distribution makers,
>>>> users and developers in making informed decisions instead of wasting
>>>> their time needlessly.
>>>>
>>>> Signed-off-by: Bartlomiej Zolnierkiewicz<bzolnier@gmail.com>
>>>> ---
>>>> drivers/ata/Kconfig | 4 ++++
>>>> 1 file changed, 4 insertions(+)
>>>>
>>>> Index: b/drivers/ata/Kconfig
>>>> ===================================================================
>>>> --- a/drivers/ata/Kconfig
>>>> +++ b/drivers/ata/Kconfig
>>>> @@ -583,6 +583,10 @@ config PATA_PDC_OLD
>>>> This option enables support for the Promise 20246, 20262, 20263,
>>>> 20265 and 20267 adapters.
>>>>
>>>> + Known issues:
>>>> + - UDMA transfers fail mysteriously on some chipsets
>>>> + - ATAPI DMA is unsupported currently
>>>
>>> Not sure this is useful, because the reports of UDMA failures are lower
>>> than most other reports. Should IPV6 have "known issues, mysterious timer
>>> list corruption" for example which occurs far more. Not do we list 'no
>>> atapi dma' in the help for the IDE SII driver ?
>>
>> If the chip can support ATAPI DMI, but the driver does not, that
>> deserves a comment, even if it's "hardware bugs prevent ATAPI DMA" or
>> "ATAPI DMA would require much more code to support, so we did not bother
>> for now"
>>
>> Ditto for things like useful ideas ("consider PIO-over-DMA in SiI 311x")
>> and other would-be-nice-to-have ideas. These can serve as projects for
>> newbies, or reminders for old-timers.
>
> The problem is that the old driver supported ATAPI DMA so people may have
> quite different expectations than in case of never-ever-implemented-ideas.

This is not rocket science :) Have one section "known issues" and
another section "fun ideas to explore." This is English code comments,
you may set any level of expectations.

Jeff