Re: [PATCH v2 2/4] HID: hid-sensor-custom: Convert sprintf/snprintf to sysfs_emit

[Jonathan Cameron]

On Thu, 14 Mar 2024 16:47:51 +0800
Li Zhijian <lizhijian@xxxxxxxxxxx> wrote:

> Per filesystems/sysfs.rst, show() should only use sysfs_emit()
> or sysfs_emit_at() when formatting the value to be returned to user space.
> 
> coccinelle complains that there are still a couple of functions that use
> snprintf(). Convert them to sysfs_emit().
> 
> sprintf() will be converted as weel if they have.
> 
> Generally, this patch is generated by
> make coccicheck M=<path/to/file> MODE=patch \
> COCCI=scripts/coccinelle/api/device_attr_show.cocci
> 
> No functional change intended
> 
> CC: Jiri Kosina <jikos@xxxxxxxxxx>
> CC: Jonathan Cameron <jic23@xxxxxxxxxx>
> CC: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
> CC: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>
> CC: linux-input@xxxxxxxxxxxxxxx
> CC: linux-iio@xxxxxxxxxxxxxxx
> Signed-off-by: Li Zhijian <lizhijian@xxxxxxxxxxx>
Hi Li Zhijian,

One trivial comment inline.
Otherwise straight forward so
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>

> ---
> This is a part of the work "Fix coccicheck device_attr_show warnings"[1]
> Split them per subsystem so that the maintainer can review it easily
> [1] https://lore.kernel.org/lkml/20240116041129.3937800-1-lizhijian@xxxxxxxxxxx/
> ---
>  drivers/hid/hid-sensor-custom.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/hid/hid-sensor-custom.c b/drivers/hid/hid-sensor-custom.c
> index d85398721659..ee1a118834f0 100644
> --- a/drivers/hid/hid-sensor-custom.c
> +++ b/drivers/hid/hid-sensor-custom.c
> @@ -155,7 +155,7 @@ static ssize_t enable_sensor_show(struct device *dev,
>  {
>  	struct hid_sensor_custom *sensor_inst = dev_get_drvdata(dev);
>  
> -	return sprintf(buf, "%d\n", sensor_inst->enable);
> +	return sysfs_emit(buf, "%d\n", sensor_inst->enable);
>  }
>  
>  static int set_power_report_state(struct hid_sensor_custom *sensor_inst,
> @@ -372,14 +372,14 @@ static ssize_t show_value(struct device *dev, struct device_attribute *attr,
>  				     sizeof(struct hid_custom_usage_desc),
>  				     usage_id_cmp);
>  		if (usage_desc)
> -			return snprintf(buf, PAGE_SIZE, "%s\n",
> -					usage_desc->desc);
> +			return sysfs_emit(buf, "%s\n",
> +					  usage_desc->desc);
rewrap the line as will be under 80 chars.

>  		else
> -			return sprintf(buf, "not-specified\n");
> +			return sysfs_emit(buf, "not-specified\n");
>  	 } else
>  		return -EINVAL;
>  
> -	return sprintf(buf, "%d\n", value);
> +	return sysfs_emit(buf, "%d\n", value);
>  }
>  
>  static ssize_t store_value(struct device *dev, struct device_attribute *attr,