[PATCH 3/3] drm/panthor: Fix undefined panthor_device_suspend/resume symbol issue

[Liviu Dudau]

On Mon, Mar 04, 2024 at 10:08:12AM +0100, Boris Brezillon wrote:
> panthor_device_resume/suspend() are only compiled when CONFIG_PM is
> enabled but panthro_drv.c doesn't use the pm_ptr() macro to conditionally
> discard resume/suspend assignments, which causes undefined symbol
> errors at link time when !PM.
> 
> We could fix that by using pm_ptr(), but supporting the !PM case makes
> little sense (the whole point of these embedded GPUs is to be low power,
> so proper PM is a basic requirement in that case). So let's just enforce
> the presence of CONFIG_PM with a Kconfig dependency instead.
> 
> If someone needs to relax this dependency, it can be done in a follow-up.
> 
> Reported-by: kernel test robot <lkp at intel.com>
> Closes: https://lore.kernel.org/oe-kbuild-all/202403031944.EOimQ8WK-lkp@intel.com/
> Signed-off-by: Boris Brezillon <boris.brezillon at collabora.com>

Reviewed-by: Liviu Dudau <liviu.dudau at arm.com>

Agree on this, there is no point on running on kernels without CONFIG_PM enabled.

Best regards,
Liviu


> ---
>  drivers/gpu/drm/panthor/Kconfig          | 1 +
>  drivers/gpu/drm/panthor/panthor_device.c | 2 --
>  2 files changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/panthor/Kconfig b/drivers/gpu/drm/panthor/Kconfig
> index 55b40ad07f3b..fdce7c1b2310 100644
> --- a/drivers/gpu/drm/panthor/Kconfig
> +++ b/drivers/gpu/drm/panthor/Kconfig
> @@ -6,6 +6,7 @@ config DRM_PANTHOR
>  	depends on ARM || ARM64 || COMPILE_TEST
>  	depends on !GENERIC_ATOMIC64  # for IOMMU_IO_PGTABLE_LPAE
>  	depends on MMU
> +	depends on PM
>  	select DEVFREQ_GOV_SIMPLE_ONDEMAND
>  	select DRM_EXEC
>  	select DRM_GEM_SHMEM_HELPER
> diff --git a/drivers/gpu/drm/panthor/panthor_device.c b/drivers/gpu/drm/panthor/panthor_device.c
> index 68e467ee458a..efea29143a54 100644
> --- a/drivers/gpu/drm/panthor/panthor_device.c
> +++ b/drivers/gpu/drm/panthor/panthor_device.c
> @@ -403,7 +403,6 @@ int panthor_device_mmap_io(struct panthor_device *ptdev, struct vm_area_struct *
>  	return 0;
>  }
>  
> -#ifdef CONFIG_PM
>  int panthor_device_resume(struct device *dev)
>  {
>  	struct panthor_device *ptdev = dev_get_drvdata(dev);
> @@ -548,4 +547,3 @@ int panthor_device_suspend(struct device *dev)
>  	mutex_unlock(&ptdev->pm.mmio_lock);
>  	return ret;
>  }
> -#endif
> -- 
> 2.43.0
> 

-- 
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