[U-Boot] [PATCH v3 5/5] ARM: dm: spi: Add support DM/DTS for i.MX28 mxs SPI driver (DM_SPI conversion)

Marek Vasut
2019-06-17T15:00:58Z

On 6/17/19 4:57 PM, Lukasz Majewski wrote:
> Hi Marek,
>
>> On 6/17/19 3:41 PM, Lukasz Majewski wrote:
>>> On Mon, 17 Jun 2019 15:23:55 +0200
>>> Marek Vasut <marex@denx.de> wrote:
>>>
>>>> On 6/17/19 2:27 PM, Lukasz Majewski wrote:
>>>>> Hi Marek,
>>>>>
>>>>>> On 6/17/19 8:49 AM, Lukasz Majewski wrote:
>>>>>>> Hi Marek,
>>>>>>>
>>>>>>>> On 6/16/19 12:34 AM, Lukasz Majewski wrote:
>>>>>>>>> This commit converts mxs_spi driver to support DM/DTS.
>>>>>>>>>
>>>>>>>>> Signed-off-by: Lukasz Majewski <lukma@denx.de>
>>>>>>>>
>>>>>>>> Is the non-DM part needed for anything ?
>>>>>>>
>>>>>>> Do you mean the non-DM part of the mxs_gpio driver? Yes, it is
>>>>>>> used by not converted boards.
>>>>>>
>>>>>> This is a SPI driver though.
>>>>>>
>>>>>>>> I recall the SPL jumps back
>>>>>>>> to BootROM when loading the U-Boot proper. So if not, drop it.
>>>>>>>>
>>>>>>>> Also, please don't do partial conversion for iMX28 only, do the
>>>>>>>> iMX23 part as well, it cannot be hard.
>>>>>>>
>>>>>>> Maybe it is not hard, but I cannot test it properly as I don't
>>>>>>> have i.MX23 device. If you are offering your help with testing
>>>>>>> (i.e. you do have the access to i.MX23 device and you will test
>>>>>>> those changes) I can add support for it.
>>>>>>>
>>>>>>> Otherwise, NO, I will not add ANY new untested code.
>>>>>>
>>>>>> In general, you don't have to add any code, the iMX23/28 SPI IP
>>>>>> is very much the same hardware, DTTO for most of the other
>>>>>> blocks. If there are any differences between iMX23/28, they are
>>>>>> already handled in the existing driver(s).
>>>>>>
>>>>>> Half-way converted drivers in fact increase maintenance burden,
>>>>>> because then we have to deal with two different variants of the
>>>>>> code, instead of only one.
>>>>>
>>>>> I cannot agree with this sentence.
>>>>
>>>> Do you think maintaining - one DM driver which supports both iMX23
>>>> and iMX28 - is more burden than maintaining - one driver which
>>>> supports DM, but only for iMX28 and non-DM for iMX23 and iMX28 ? I
>>>> don't think so.
>>>>
>>>>> The conversion would be done for
>>>>> i.MX28, which is then tested and validated (and clearly stated in
>>>>> the cover letter/commit message that only supported was i.MX28).>
>>>>> If I don't need to adjust common, reused code (which already
>>>>> supports both variants as it is the case with mxs_spi.c), then I
>>>>> don't mind.
>>>>
>>>> Well, that is what I said above, you don't.
>>>
>>> To make myself clear - If I can reuse the common code (which
>>> supports both imx23 and 28) for DM/DTS conversion then I'm OK with
>>> doing so.
>>>
>>> If you require me to add untested code specific to i.MX23 - then
>>> NO.
>>
>> Yes, you can.
>
> If possible, by reusing the old, common working code, I can add this to
> the converted driver.

Again, yes, you can. All the code is already in the driver.

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--
Best regards,
Marek Vasut