Re: [PATCH v3] ASoC: atmel: ATMEL drivers don't need HAS_DMA

[Randy Dunlap <rdunlap@infradead.org>]

On 9/6/21 12:14 AM, Geert Uytterhoeven wrote:
> Hi Randy,
> 
> On Fri, Sep 3, 2021 at 9:53 PM Randy Dunlap <rdunlap@infradead.org> wrote:
>> On 9/2/21 9:44 AM, Geert Uytterhoeven wrote:
>>> On Thu, Jul 8, 2021 at 6:51 PM Randy Dunlap <rdunlap@infradead.org> wrote:
>>>> On 7/8/21 1:19 AM, Codrin.Ciubotariu@microchip.com wrote:
>>>>> On 08.07.2021 00:47, Randy Dunlap wrote:
>>>>>> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
>>>>>>
>>>>>> On a config (such as arch/sh/) which does not set HAS_DMA when MMU
>>>>>> is not set, several ATMEL ASoC drivers select symbols that cause
>>>>>> kconfig warnings. There is one "depends on HAS_DMA" which is no longer
>>>>>> needed. Dropping it eliminates the kconfig warnings and still builds
>>>>>> with no problems reported.
>>>>>>
>>>>>> Fix the following kconfig warnings:
>>>>>>
>>>>>> WARNING: unmet direct dependencies detected for SND_ATMEL_SOC_PDC
>>>>>>      Depends on [n]: SOUND [=m] && !UML && SND [=m] && SND_SOC [=m] && SND_ATMEL_SOC [=m] && HAS_DMA [=n]
>>>>>>      Selected by [m]:
>>>>>>      - SND_ATMEL_SOC_SSC [=m] && SOUND [=m] && !UML && SND [=m] && SND_SOC [=m] && SND_ATMEL_SOC [=m]
>>>>>>      - SND_ATMEL_SOC_SSC_PDC [=m] && SOUND [=m] && !UML && SND [=m] && SND_SOC [=m] && SND_ATMEL_SOC [=m] && ATMEL_SSC [=m]
>>>>>>
>>>>>> WARNING: unmet direct dependencies detected for SND_ATMEL_SOC_SSC_PDC
>>>>>>      Depends on [n]: SOUND [=m] && !UML && SND [=m] && SND_SOC [=m] && SND_ATMEL_SOC [=m] && ATMEL_SSC [=m] && HAS_DMA [=n]
>>>>>>      Selected by [m]:
>>>>>>      - SND_AT91_SOC_SAM9G20_WM8731 [=m] && SOUND [=m] && !UML && SND [=m] && SND_SOC [=m] && SND_ATMEL_SOC [=m] && (ARCH_AT91 || COMPILE_TEST [=y]) && ATMEL_SSC [=m] && SND_SOC_I2C_AND_SPI [=m]
>>>>>>
>>>>>> WARNING: unmet direct dependencies detected for SND_ATMEL_SOC_SSC
>>>>>>      Depends on [n]: SOUND [=m] && !UML && SND [=m] && SND_SOC [=m] && SND_ATMEL_SOC [=m] && HAS_DMA [=n]
>>>>>>      Selected by [m]:
>>>>>>      - SND_ATMEL_SOC_SSC_DMA [=m] && SOUND [=m] && !UML && SND [=m] && SND_SOC [=m] && SND_ATMEL_SOC [=m] && ATMEL_SSC [=m]
>>>>>>
>>>>>> WARNING: unmet direct dependencies detected for SND_ATMEL_SOC_SSC_DMA
>>>>>>      Depends on [n]: SOUND [=m] && !UML && SND [=m] && SND_SOC [=m] && SND_ATMEL_SOC [=m] && ATMEL_SSC [=m] && HAS_DMA [=n]
>>>>>>      Selected by [m]:
>>>>>>      - SND_ATMEL_SOC_WM8904 [=m] && SOUND [=m] && !UML && SND [=m] && SND_SOC [=m] && SND_ATMEL_SOC [=m] && (ARCH_AT91 || COMPILE_TEST [=y]) && ATMEL_SSC [=m] && I2C [=m]
>>>>>>      - SND_AT91_SOC_SAM9X5_WM8731 [=m] && SOUND [=m] && !UML && SND [=m] && SND_SOC [=m] && SND_ATMEL_SOC [=m] && (ARCH_AT91 || COMPILE_TEST [=y]) && ATMEL_SSC [=m] && SND_SOC_I2C_AND_SPI [=m]
>>>>>>
>>>>>> Fixes: 3951e4aae2ce ("ASoC: atmel-pcm: dma support based on pcm dmaengine")
>>>>>> Fixes: 18291410557f ("ASoC: atmel: enable SOC_SSC_PDC and SOC_SSC_DMA in Kconfig")
>>>>>> Fixes: 061981ff8cc8 ("ASoC: atmel: properly select dma driver state")
>>>>>
>>>>> I am not sure about these fixes tags. As Alexandre mentioned, it looks
>>>>> like the reason for HAS_DMA in the first place was the COMPILE_TEST with
>>>>> m32r arch. I dig a bit, and, if any, I think we should use:
>>>>> Fixes: eb17726b00b3 ("m32r: add simple dma")
>>>>> since this commit adds dummy DMA support for m32r and seems to fix the
>>>>> HAS_DMA dependency.
>>>>
>>>> Ah, I forgot to update the Fixes: tag(s).
>>>>
>>>> I won't disagree with your Fixes: suggestion (good digging) but
>>>> I would probably have used 8d7d11005e930:
>>>>     ASoC: atmel: fix build failure
>>>> which is the commit that added "depends on HAS_DMA".
>>>
>>> M32r was not the only platform NO_DMA, so I guess the build would
>>> have failed for the others, too (e.g. Sun-3).
>>>
>>> So the real fix was probably commit f29ab49b5388b2f8 ("dma-mapping:
>>> Convert NO_DMA get_dma_ops() into a real dummy"), or one of the
>>> related commits adding dummies to subsystems.
>>
>> Hi Geert,
>> Does this mean that some other actions are needed here?
>> E.g. revert + a different kind of fix?
> 
> While we can now compile drivers using DMA features on NO_DMA
> platforms, thanks to the dummies, it does mean many of these drivers
> cannot work on such platforms.  So I think it makes sense to replace
> "depends on HAS_DMA" by "depends on HAS_DMA || COMPILE_TEST" if DMA
> is not optional to the driver.

Hi Geert,

Is this what you had in mind?  It seems to work with my (limited)
testing.

thanks.

---
  sound/soc/atmel/Kconfig |    1 +
  1 file changed, 1 insertion(+)

--- linux-next-20210907.orig/sound/soc/atmel/Kconfig
+++ linux-next-20210907/sound/soc/atmel/Kconfig
@@ -11,6 +11,7 @@ if SND_ATMEL_SOC
  
  config SND_ATMEL_SOC_PDC
  	bool
+	depends on HAS_DMA || COMPILE_TEST
  
  config SND_ATMEL_SOC_DMA
  	bool