[PATCH] serial: 8250: Fix THRE flag usage for CAP_MINI

[Phil Elwell]

On 28/06/2017 08:48, Andy Shevchenko wrote:
> On Tue, 2017-06-27 at 22:00 +0100, Phil Elwell wrote:
>> On 27/06/2017 18:52, Andy Shevchenko wrote:
>>> On Tue, 2017-06-27 at 11:30 +0100, Phil Elwell wrote:
>>>> On 27/06/2017 10:15, Andy Shevchenko wrote:
>>>>> On Mon, 2017-06-26 at 16:15 +0100, Phil Elwell wrote:
> 
>>>>>> Besides, the "HFIFO" capability looks a lot like quirk to me.
>>>>>
>>>>> To me either, which raises a question "Should it be fixed
>>>>> accordingly?"
>>>>
>>>> If I was going to make these quirks, are we simply talking about
>>>> renaming the
>>>> capability or is there another mechanism? I've found the 8250_pci
>>>> quirks, and
>>>> they look quite different.
>>>
>>> Okay, we have several types of flags in the code
>>> 1. Capabilities: UART_CAP: looks like it defines features of
>>> hardware
>>> solely for 8250 compatible devices.
>>> 2. Flags as quirks UPF_<something, not all of them> (I have a patch
>>> to
>>> convert them to quirks, need by the way to update and resend): they
>>> are
>>> for any serial devices.
>>> 3. Flags as capabilities: UPF_<the rest>, similar function as
>>> UART_CAP,
>>> but for any serial device.
>>>
>>>>
>>>> I'm also happy to make this code conditional on
>>>> CONFIG_SERIAL_8250_BCM2835AUX
>>>> if that is more acceptable.
>>>
>>> No, it is undesired.
>>>
>>> Can you describe which one from the above suits the best for your
>>> case?
>>
>> This bug I am trying to work around is found in the 8250
>> implementation of
>> one family of CPUs, so I would say capabilities are the best fit
>> because
>> they are specific to 8250 drivers.
> 
> Yeah, looks like UART_CAP suits the best for now.
> 
> One more comment that UART_CAP_* gather capabilities and quirks at the
> same time.

Is that a request for an additional comment? Is there anything else needed
for an ack?

Thanks,

Phil