Re: [PATCH] media: pvrusb2: use sysfs_emit() to instead of scnprintf()

[Tommaso Merciai]

Hi,

On Thu, Dec 01, 2022 at 07:27:59PM +0800, ye.xingchen@xxxxxxxxxx wrote:
> From: ye xingchen <ye.xingchen@xxxxxxxxxx>
> 
> Follow the advice of the Documentation/filesystems/sysfs.rst and show()
> should only use sysfs_emit() or sysfs_emit_at() when formatting the
> value to be returned to user space.
> 
> Signed-off-by: ye xingchen <ye.xingchen@xxxxxxxxxx>
> ---
>  drivers/media/usb/pvrusb2/pvrusb2-sysfs.c | 20 ++++++++++----------
>  1 file changed, 10 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/media/usb/pvrusb2/pvrusb2-sysfs.c b/drivers/media/usb/pvrusb2/pvrusb2-sysfs.c
> index 3e42e209be37..81c8b65bd9ef 100644
> --- a/drivers/media/usb/pvrusb2/pvrusb2-sysfs.c
> +++ b/drivers/media/usb/pvrusb2/pvrusb2-sysfs.c
> @@ -81,7 +81,7 @@ static ssize_t show_name(struct device *class_dev,
>  	pvr2_sysfs_trace("pvr2_sysfs(%p) show_name(cid=%d) is %s",
>  			 cip->chptr, cip->ctl_id, name);
>  	if (!name) return -EINVAL;
> -	return scnprintf(buf, PAGE_SIZE, "%s\n", name);
> +	return sysfs_emit(buf, "%s\n", name);
>  }
> 
>  static ssize_t show_type(struct device *class_dev,
> @@ -102,7 +102,7 @@ static ssize_t show_type(struct device *class_dev,
>  	}
>  	pvr2_sysfs_trace("pvr2_sysfs(%p) show_type(cid=%d) is %s",
>  			 cip->chptr, cip->ctl_id, name);
> -	return scnprintf(buf, PAGE_SIZE, "%s\n", name);
> +	return sysfs_emit(buf, "%s\n", name);
>  }
> 
>  static ssize_t show_min(struct device *class_dev,
> @@ -115,7 +115,7 @@ static ssize_t show_min(struct device *class_dev,
>  	val = pvr2_ctrl_get_min(cip->cptr);
>  	pvr2_sysfs_trace("pvr2_sysfs(%p) show_min(cid=%d) is %ld",
>  			 cip->chptr, cip->ctl_id, val);
> -	return scnprintf(buf, PAGE_SIZE, "%ld\n", val);
> +	return sysfs_emit(buf, "%ld\n", val);
>  }
> 
>  static ssize_t show_max(struct device *class_dev,
> @@ -128,7 +128,7 @@ static ssize_t show_max(struct device *class_dev,
>  	val = pvr2_ctrl_get_max(cip->cptr);
>  	pvr2_sysfs_trace("pvr2_sysfs(%p) show_max(cid=%d) is %ld",
>  			 cip->chptr, cip->ctl_id, val);
> -	return scnprintf(buf, PAGE_SIZE, "%ld\n", val);
> +	return sysfs_emit(buf, "%ld\n", val);
>  }
> 
>  static ssize_t show_def(struct device *class_dev,
> @@ -551,7 +551,7 @@ static ssize_t v4l_minor_number_show(struct device *class_dev,
>  	struct pvr2_sysfs *sfp;
>  	sfp = dev_get_drvdata(class_dev);
>  	if (!sfp) return -EINVAL;
> -	return scnprintf(buf,PAGE_SIZE,"%d\n",
> +	return sysfs_emit(buf, "%d\n",
>  			 pvr2_hdw_v4l_get_minor_number(sfp->channel.hdw,
>  						       pvr2_v4l_type_video));
>  }
> @@ -563,7 +563,7 @@ static ssize_t bus_info_show(struct device *class_dev,
>  	struct pvr2_sysfs *sfp;
>  	sfp = dev_get_drvdata(class_dev);
>  	if (!sfp) return -EINVAL;
> -	return scnprintf(buf,PAGE_SIZE,"%s\n",
> +	return sysfs_emit(buf, "%s\n",
>  			 pvr2_hdw_get_bus_info(sfp->channel.hdw));
>  }
> 
> @@ -574,7 +574,7 @@ static ssize_t hdw_name_show(struct device *class_dev,
>  	struct pvr2_sysfs *sfp;
>  	sfp = dev_get_drvdata(class_dev);
>  	if (!sfp) return -EINVAL;
> -	return scnprintf(buf,PAGE_SIZE,"%s\n",
> +	return sysfs_emit(buf, "%s\n",
>  			 pvr2_hdw_get_type(sfp->channel.hdw));
>  }
> 
> @@ -585,7 +585,7 @@ static ssize_t hdw_desc_show(struct device *class_dev,
>  	struct pvr2_sysfs *sfp;
>  	sfp = dev_get_drvdata(class_dev);
>  	if (!sfp) return -EINVAL;
> -	return scnprintf(buf,PAGE_SIZE,"%s\n",
> +	return sysfs_emit(buf, "%s\n",
>  			 pvr2_hdw_get_desc(sfp->channel.hdw));
>  }
> 
> @@ -597,7 +597,7 @@ static ssize_t v4l_radio_minor_number_show(struct device *class_dev,
>  	struct pvr2_sysfs *sfp;
>  	sfp = dev_get_drvdata(class_dev);
>  	if (!sfp) return -EINVAL;
> -	return scnprintf(buf,PAGE_SIZE,"%d\n",
> +	return sysfs_emit(buf, "%d\n",
>  			 pvr2_hdw_v4l_get_minor_number(sfp->channel.hdw,
>  						       pvr2_v4l_type_radio));
>  }
> @@ -609,7 +609,7 @@ static ssize_t unit_number_show(struct device *class_dev,
>  	struct pvr2_sysfs *sfp;
>  	sfp = dev_get_drvdata(class_dev);
>  	if (!sfp) return -EINVAL;
> -	return scnprintf(buf,PAGE_SIZE,"%d\n",
> +	return sysfs_emit(buf, "%d\n",
>  			 pvr2_hdw_get_unit_number(sfp->channel.hdw));
>  }
> 
> -- 
> 2.25.1

Looks good to me.
Reviewed-by: Tommaso Merciai <tommaso.merciai@xxxxxxxxxxxxxxxxxxxx>

-- 
Tommaso Merciai
Embedded Linux Engineer
tommaso.merciai@xxxxxxxxxxxxxxxxxxxx
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