[PATCH] firmware: arm_scmi: fix i.MX build dependency

[Shawn Guo]

On Sat, Nov 16, 2024 at 12:05:18AM +0100, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd at arndb.de>
> 
> The newly added SCMI vendor driver references functions in the
> protocol driver but needs a Kconfig dependency to ensure it can link,
> essentially the Kconfig dependency needs to be reversed to match the
> link time dependency:
> 
> arm-linux-gnueabi-ld: sound/soc/fsl/fsl_mqs.o: in function `fsl_mqs_sm_write':
> fsl_mqs.c:(.text+0x1aa): undefined reference to `scmi_imx_misc_ctrl_set'
> arm-linux-gnueabi-ld: sound/soc/fsl/fsl_mqs.o: in function `fsl_mqs_sm_read':
> fsl_mqs.c:(.text+0x1ee): undefined reference to `scmi_imx_misc_ctrl_get'
> 
> This however only works after changing the dependency in the SND_SOC_FSL_MQS
> driver as well, which uses 'select IMX_SCMI_MISC_DRV' to turn on a
> driver it depends on. This is generally a bad idea, so the best solution
> is to change that into a dependency.
> 
> To allow the ASoC driver to keep building with the SCMI support, this
> needs to be an optional dependency that enforces the link-time
> dependency if IMX_SCMI_MISC_DRV is a loadable module but not
> depend on it if that is disabled.
> 
> Fixes: 61c9f03e22fc ("firmware: arm_scmi: Add initial support for i.MX MISC protocol")
> Fixes: 101c9023594a ("ASoC: fsl_mqs: Support accessing registers by scmi interface")
> Signed-off-by: Arnd Bergmann <arnd at arndb.de>
> ---
> I'm not sure this is the version we want to go with in the end, without
> having read the code in detail, but the version in linux-next is clearly
> wrong in multiple ways and this is the best I could come up with so far.
> 
> If we can agree on this approach, it needs to go through the ASoC tree
> as that contains the 101c9023594a commit at the moment.

Thanks for spotting and fixing, Arnd!

Unless Peng has objection to this change, I'm good with it.

Shawn