Commit 9e23bf6b authored by Andy Shevchenko's avatar Andy Shevchenko Committed by Bartosz Golaszewski
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gpiolib: Use sysfs_emit() in "show" functions 



The sysfs_emit() function was introduced to make it less ambiguous
which function is preferred when writing to the output buffer in
a "show" callback [1].

Convert the GPIO library sysfs interface from sprintf() to sysfs_emit()
accordingly, as the latter is aware of the PAGE_SIZE buffer and correctly
returns the number of bytes written into the buffer.

No functional change intended.

[1] Documentation/filesystems/sysfs.rst

Signed-off-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: default avatarBartosz Golaszewski <bgolaszewski@baylibre.com>
parent fd80b8ba

drivers/gpio/gpiolib-sysfs.c

+12 −17
Original line number Diff line number Diff line
@@ -66,9 +66,8 @@ static ssize_t direction_show(struct device *dev, 
	mutex_lock(&data->mutex);



	gpiod_get_direction(desc);

	status = sprintf(buf, "%s\n",

			test_bit(FLAG_IS_OUT, &desc->flags)

				? "out" : "in");

	status = sysfs_emit(buf, "%s\n",

			    test_bit(FLAG_IS_OUT, &desc->flags) ? "out" : "in");



	mutex_unlock(&data->mutex);
@@ -109,13 +108,9 @@ static ssize_t value_show(struct device *dev, 
	mutex_lock(&data->mutex);



	status = gpiod_get_value_cansleep(desc);

	if (status < 0)

		goto err;

	if (status >= 0)

		status = sysfs_emit(buf, "%zd\n", status);



	buf[0] = '0' + status;

	buf[1] = '\n';

	status = 2;

err:

	mutex_unlock(&data->mutex);



	return status;
@@ -249,11 +244,11 @@ static ssize_t edge_show(struct device *dev, 
	mutex_lock(&data->mutex);



	for (i = 0; i < ARRAY_SIZE(trigger_types); i++) {

		if (data->irq_flags == trigger_types[i].flags) {

			status = sprintf(buf, "%s\n", trigger_types[i].name);

		if (data->irq_flags == trigger_types[i].flags)

			break;

	}

	}

	if (i < ARRAY_SIZE(trigger_types))

		status = sysfs_emit(buf, "%s\n", trigger_types[i].name);



	mutex_unlock(&data->mutex);
@@ -333,7 +328,7 @@ static ssize_t active_low_show(struct device *dev, 


	mutex_lock(&data->mutex);



	status = sprintf(buf, "%d\n",

	status = sysfs_emit(buf, "%d\n",

			    !!test_bit(FLAG_ACTIVE_LOW, &desc->flags));



	mutex_unlock(&data->mutex);
@@ -412,7 +407,7 @@ static ssize_t base_show(struct device *dev, 
{

	const struct gpio_chip	*chip = dev_get_drvdata(dev);



	return sprintf(buf, "%d\n", chip->base);

	return sysfs_emit(buf, "%d\n", chip->base);

}

static DEVICE_ATTR_RO(base);
@@ -421,7 +416,7 @@ static ssize_t label_show(struct device *dev, 
{

	const struct gpio_chip	*chip = dev_get_drvdata(dev);



	return sprintf(buf, "%s\n", chip->label ? : "");

	return sysfs_emit(buf, "%s\n", chip->label ?: "");

}

static DEVICE_ATTR_RO(label);
@@ -430,7 +425,7 @@ static ssize_t ngpio_show(struct device *dev, 
{

	const struct gpio_chip	*chip = dev_get_drvdata(dev);



	return sprintf(buf, "%u\n", chip->ngpio);

	return sysfs_emit(buf, "%u\n", chip->ngpio);

}

static DEVICE_ATTR_RO(ngpio);