[PATCH v2] drm: Make drm.debug parameter description more helpful

[Jani Nikula]

On Wed, 20 Apr 2016, Ezequiel Garcia <ezequiel at vanguardiasur.com.ar> wrote:
> Let's be user-friendly and print an actually helpful parameter
> description.
>
> This makes modinfo output the debug parameter like this:
>
> parm:           debug:Enable debug output, where each bit enables a debug category.
> 		Bit 0 (0x01) will enable CORE messages (drm core code)
> 		Bit 1 (0x02) will enable DRIVER messages (drm controller code)
> 		Bit 2 (0x04) will enable KMS messages (modesetting code)
> 		Bit 3 (0x08) will enable PRIME messages (prime code)
> 		Bit 4 (0x10) will enable ATOMIC messages (atomic code)
> 		Bit 5 (0x20) will enable VBL messages (vblank code) (int)
>
> Signed-off-by: Ezequiel Garcia <ezequiel at vanguardiasur.com.ar>

Reviewed-by: Jani Nikula <jani.nikula at intel.com>



> --
> Changes from v1:
>
>   * Fixed s/PRMIE/PRIME typo.
>   * Add ATOMIC and VBL debug parameter documentation.
>   * Prefix the continuation lines with two tabs and
>     removed the last new line.
>   * Remove spurious whitespace.
>
>  drivers/gpu/drm/drm_drv.c | 14 ++++++++++++--
>  1 file changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
> index 167c8d3d4a31..c4f45ac04ea4 100644
> --- a/drivers/gpu/drm/drm_drv.c
> +++ b/drivers/gpu/drm/drm_drv.c
> @@ -37,13 +37,23 @@
>  #include "drm_legacy.h"
>  #include "drm_internal.h"
>  
> -unsigned int drm_debug = 0;	/* bitmask of DRM_UT_x */
> +/*
> + * drm_debug: Enable debug output.
> + * Bitmask of DRM_UT_x. See include/drm/drmP.h for details.
> + */
> +unsigned int drm_debug = 0;
>  EXPORT_SYMBOL(drm_debug);
>  
>  MODULE_AUTHOR(CORE_AUTHOR);
>  MODULE_DESCRIPTION(CORE_DESC);
>  MODULE_LICENSE("GPL and additional rights");
> -MODULE_PARM_DESC(debug, "Enable debug output");
> +MODULE_PARM_DESC(debug, "Enable debug output, where each bit enables a debug category.\n"
> +"\t\tBit 0 (0x01) will enable CORE messages (drm core code)\n"
> +"\t\tBit 1 (0x02) will enable DRIVER messages (drm controller code)\n"
> +"\t\tBit 2 (0x04) will enable KMS messages (modesetting code)\n"
> +"\t\tBit 3 (0x08) will enable PRIME messages (prime code)\n"
> +"\t\tBit 4 (0x10) will enable ATOMIC messages (atomic code)\n"
> +"\t\tBit 5 (0x20) will enable VBL messages (vblank code)");
>  module_param_named(debug, drm_debug, int, 0600);
>  
>  static DEFINE_SPINLOCK(drm_minor_lock);

-- 
Jani Nikula, Intel Open Source Technology Center