Re: [PATCH v9 10/14] drm/xe/hwmon: Add platform-aware VRAM thermal channel support

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] hwmon: DRM driver implements hwmon directly instead of as auxiliary device
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commit 55ff84e7912b9e195885552d6a750a68cc2c19d9
Author: Karthik Poosa <karthik.poosa@intel.com>

drm/xe/hwmon: Add platform-aware VRAM thermal channel support

On CRI, this derives the number of available VRAM temperature channels from
the CRI_MSU_VRAM_ENABLE register. It increases the maximum supported VRAM
channel count to 80 and uses the derived count to control VRAM sensor
enumeration, channel access, and VRAM label allocation.

> diff --git a/drivers/gpu/drm/xe/xe_hwmon.c b/drivers/gpu/drm/xe/xe_hwmon.c
> index bafa175f84578..9d83d9d2286ed 100644
> --- a/drivers/gpu/drm/xe/xe_hwmon.c
> +++ b/drivers/gpu/drm/xe/xe_hwmon.c
[ ... ]
> @@ -1683,7 +1809,9 @@ int xe_hwmon_register(struct xe_device *xe)
>  	hwmon->xe = xe;
>  	xe->hwmon = hwmon;
>  
> -	xe_hwmon_get_preregistration_info(hwmon);
> +	ret = xe_hwmon_get_preregistration_info(hwmon);
> +	if (ret)
> +		goto err_null_hwmon;
>  
>  	drm_dbg(&xe->drm, "Register xe hwmon interface\n");
>  
> @@ -1693,10 +1821,14 @@ int xe_hwmon_register(struct xe_device *xe)
>  								hwmon_groups);

[Severity: Low]
The hwmon subsystem guidelines state that if a chip's main functionality
is not hardware monitoring (such as a DRM controller), its hardware
monitoring functionality should be implemented as an auxiliary device
driver residing in drivers/hwmon/.

Does registering the hardware monitoring device directly from within the 
drivers/gpu/drm/ subsystem bypass these structural layering rules?

>  	if (IS_ERR(hwmon->hwmon_dev)) {
>  		drm_err(&xe->drm, "Failed to register xe hwmon (%pe)\n", hwmon->hwmon_dev);
> -		xe->hwmon = NULL;
> -		return PTR_ERR(hwmon->hwmon_dev);
> +		ret = PTR_ERR(hwmon->hwmon_dev);
> +		goto err_null_hwmon;
>  	}
>  
>  	return 0;
> +
> +err_null_hwmon:
> +	xe->hwmon = NULL;
> +	return ret;
>  }
>  MODULE_IMPORT_NS("INTEL_PMT_TELEMETRY");

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Sashiko AI review · https://sashiko.dev/#/patchset/20261009120335.52973-1-karthik.poosa@intel.com?part=10