[PATCH] iio: adc: ad7816: use sysfs_emit() instead of sprintf()

[PATCH] iio: adc: ad7816: use sysfs_emit() instead of sprintf()

[Minu Jin]

Replace sprintf() with sysfs_emit().
sysfs_emit() is preferred than sprintf() in show() functions.
It has aware of the PAGE_SIZE buffer limit and ensures safe buffer handling.

Signed-off-by: Minu Jin <s9430939@naver.com>
---
 drivers/staging/iio/adc/ad7816.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/staging/iio/adc/ad7816.c b/drivers/staging/iio/adc/ad7816.c
index 172acf135f3b..0e32a2295990 100644
--- a/drivers/staging/iio/adc/ad7816.c
+++ b/drivers/staging/iio/adc/ad7816.c
@@ -124,8 +124,8 @@ static ssize_t ad7816_show_mode(struct device *dev,
 	struct ad7816_chip_info *chip = iio_priv(indio_dev);
 
 	if (chip->mode)
-		return sprintf(buf, "power-save\n");
-	return sprintf(buf, "full\n");
+		return sysfs_emit(buf, "power-save\n");
+	return sysfs_emit(buf, "full\n");
 }
 
 static ssize_t ad7816_store_mode(struct device *dev,
@@ -156,7 +156,7 @@ static ssize_t ad7816_show_available_modes(struct device *dev,
 					   struct device_attribute *attr,
 					   char *buf)
 {
-	return sprintf(buf, "full\npower-save\n");
+	return sysfs_emit(buf, "full\npower-save\n");
 }
 
 static IIO_DEVICE_ATTR(available_modes, 0444, ad7816_show_available_modes,
@@ -169,7 +169,7 @@ static ssize_t ad7816_show_channel(struct device *dev,
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct ad7816_chip_info *chip = iio_priv(indio_dev);
 
-	return sprintf(buf, "%d\n", chip->channel_id);
+	return sysfs_emit(buf, "%d\n", chip->channel_id);
 }
 
 static ssize_t ad7816_store_channel(struct device *dev,
@@ -231,9 +231,9 @@ static ssize_t ad7816_show_value(struct device *dev,
 		data &= AD7816_TEMP_FLOAT_MASK;
 		if (value < 0)
 			data = BIT(AD7816_TEMP_FLOAT_OFFSET) - data;
-		return sprintf(buf, "%d.%.2d\n", value, data * 25);
+		return sysfs_emit(buf, "%d.%.2d\n", value, data * 25);
 	}
-	return sprintf(buf, "%u\n", data);
+	return sysfs_emit(buf, "%u\n", data);
 }
 
 static IIO_DEVICE_ATTR(value, 0444, ad7816_show_value, NULL, 0);
@@ -281,9 +281,9 @@ static ssize_t ad7816_show_oti(struct device *dev,
 		value = AD7816_BOUND_VALUE_MIN +
 			(chip->oti_data[chip->channel_id] -
 			AD7816_BOUND_VALUE_BASE);
-		return sprintf(buf, "%d\n", value);
+		return sysfs_emit(buf, "%d\n", value);
 	}
-	return sprintf(buf, "%u\n", chip->oti_data[chip->channel_id]);
+	return sysfs_emit(buf, "%u\n", chip->oti_data[chip->channel_id]);
 }
 
 static inline ssize_t ad7816_set_oti(struct device *dev,
-- 
2.43.0

Re: [PATCH] iio: adc: ad7816: use sysfs_emit() instead of sprintf()

[Greg KH]

On Mon, Apr 20, 2026 at 08:27:20PM +0900, Minu Jin wrote:
> Replace sprintf() with sysfs_emit().
> sysfs_emit() is preferred than sprintf() in show() functions.

For _new_ functions, not existing ones.

> It has aware of the PAGE_SIZE buffer limit and ensures safe buffer handling.

Are any of the current usages incorrect?  If not, no need to change
this.

thanks,

greg k-h

Re: [PATCH] iio: adc: ad7816: use sysfs_emit() instead of sprintf()

[Jonathan Cameron]

On Mon, 20 Apr 2026 14:30:05 +0200
Greg KH <gregkh@linuxfoundation.org> wrote:

> On Mon, Apr 20, 2026 at 08:27:20PM +0900, Minu Jin wrote:
> > Replace sprintf() with sysfs_emit().
> > sysfs_emit() is preferred than sprintf() in show() functions.  
> 
> For _new_ functions, not existing ones.
> 
> > It has aware of the PAGE_SIZE buffer limit and ensures safe buffer handling.  
> 
> Are any of the current usages incorrect?  If not, no need to change
> this.
> 

I wouldn't mind it if part of more general cleanup and modernisation, particularly
if that was touching the relevant bit of the code.

Before sending a patch check if anything similar is on list.
There is one other near identical one I rejected and a more significant
cleanup series that is undergoing revisions...

Thanks,

Jonathan

> thanks,
> 
> greg k-h
>