[PATCH] amdgpu_dm: no need to check return value of debugfs_create functions

[Kazlauskas, Nicholas]

On 6/13/19 9:20 AM, Greg Kroah-Hartman wrote:
> When calling debugfs functions, there is no need to ever check the
> return value.  The function can work or not, but the code logic should
> never do something different based on this.
> 
> Cc: Harry Wentland <harry.wentland at amd.com>
> Cc: Leo Li <sunpeng.li at amd.com>
> Cc: Alex Deucher <alexander.deucher at amd.com>
> Cc: "Christian König" <christian.koenig at amd.com>
> Cc: "David (ChunMing) Zhou" <David1.Zhou at amd.com>
> Cc: David Airlie <airlied at linux.ie>
> Cc: Daniel Vetter <daniel at ffwll.ch>
> Cc: Nicholas Kazlauskas <nicholas.kazlauskas at amd.com>
> Cc: David Francis <David.Francis at amd.com>
> Cc: Mario Kleiner <mario.kleiner.de at gmail.com>
> Cc: Bhawanpreet Lakha <Bhawanpreet.Lakha at amd.com>
> Cc: Anthony Koo <Anthony.Koo at amd.com>
> Cc: hersen wu <hersenxs.wu at amd.com>
> Cc: "Leo (Hanghong) Ma" <hanghong.ma at amd.com>
> Cc: amd-gfx at lists.freedesktop.org
> Cc: dri-devel at lists.freedesktop.org
> Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>

Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas at amd.com>

I'll keep this in mind when we're adding more of these entries - the 
functions do seem to check internally, so this makes the code a little 
simpler.

Thanks!

Nicholas Kazlauskas

> ---
>   .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c |  6 +---
>   .../amd/display/amdgpu_dm/amdgpu_dm_debugfs.c | 35 ++++++-------------
>   .../amd/display/amdgpu_dm/amdgpu_dm_debugfs.h |  2 +-
>   3 files changed, 12 insertions(+), 31 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index bcb1a93c0b4c..cd10b0825087 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -4825,11 +4825,7 @@ static int amdgpu_dm_connector_init(struct amdgpu_display_manager *dm,
>   
>   	drm_connector_register(&aconnector->base);
>   #if defined(CONFIG_DEBUG_FS)
> -	res = connector_debugfs_init(aconnector);
> -	if (res) {
> -		DRM_ERROR("Failed to create debugfs for connector");
> -		goto out_free;
> -	}
> +	connector_debugfs_init(aconnector);
>   	aconnector->debugfs_dpcd_address = 0;
>   	aconnector->debugfs_dpcd_size = 0;
>   #endif
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
> index 1d5fc5ad3bee..2b9ea1b67c9a 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
> @@ -873,25 +873,19 @@ static const struct {
>   		{"aux_dpcd_data", &dp_dpcd_data_debugfs_fops}
>   };
>   
> -int connector_debugfs_init(struct amdgpu_dm_connector *connector)
> +void connector_debugfs_init(struct amdgpu_dm_connector *connector)
>   {
>   	int i;
> -	struct dentry *ent, *dir = connector->base.debugfs_entry;
> +	struct dentry *dir = connector->base.debugfs_entry;
>   
>   	if (connector->base.connector_type == DRM_MODE_CONNECTOR_DisplayPort ||
>   	    connector->base.connector_type == DRM_MODE_CONNECTOR_eDP) {
>   		for (i = 0; i < ARRAY_SIZE(dp_debugfs_entries); i++) {
> -			ent = debugfs_create_file(dp_debugfs_entries[i].name,
> -						  0644,
> -						  dir,
> -						  connector,
> -						  dp_debugfs_entries[i].fops);
> -			if (IS_ERR(ent))
> -				return PTR_ERR(ent);
> +			debugfs_create_file(dp_debugfs_entries[i].name,
> +					    0644, dir, connector,
> +					    dp_debugfs_entries[i].fops);
>   		}
>   	}
> -
> -	return 0;
>   }
>   
>   /*
> @@ -1034,7 +1028,7 @@ int dtn_debugfs_init(struct amdgpu_device *adev)
>   	};
>   
>   	struct drm_minor *minor = adev->ddev->primary;
> -	struct dentry *ent, *root = minor->debugfs_root;
> +	struct dentry *root = minor->debugfs_root;
>   	int ret;
>   
>   	ret = amdgpu_debugfs_add_files(adev, amdgpu_dm_debugfs_list,
> @@ -1042,20 +1036,11 @@ int dtn_debugfs_init(struct amdgpu_device *adev)
>   	if (ret)
>   		return ret;
>   
> -	ent = debugfs_create_file(
> -		"amdgpu_dm_dtn_log",
> -		0644,
> -		root,
> -		adev,
> -		&dtn_log_fops);
> -
> -	if (IS_ERR(ent))
> -		return PTR_ERR(ent);
> +	debugfs_create_file("amdgpu_dm_dtn_log", 0644, root, adev,
> +			    &dtn_log_fops);
>   
> -	ent = debugfs_create_file_unsafe("amdgpu_dm_visual_confirm", 0644, root,
> -					 adev, &visual_confirm_fops);
> -	if (IS_ERR(ent))
> -		return PTR_ERR(ent);
> +	debugfs_create_file_unsafe("amdgpu_dm_visual_confirm", 0644, root, adev,
> +				   &visual_confirm_fops);
>   
>   	return 0;
>   }
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.h
> index bdef1587b0a0..5e5b2b2afa31 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.h
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.h
> @@ -29,7 +29,7 @@
>   #include "amdgpu.h"
>   #include "amdgpu_dm.h"
>   
> -int connector_debugfs_init(struct amdgpu_dm_connector *connector);
> +void connector_debugfs_init(struct amdgpu_dm_connector *connector);
>   int dtn_debugfs_init(struct amdgpu_device *adev);
>   
>   #endif
>