Commit ade79563 authored by Takashi Iwai's avatar Takashi Iwai
Browse files

ALSA: control-led: Replace sprintf() with sysfs_emit() 

For sysfs outputs, it's safer to use a new helper, sysfs_emit(),
instead of the raw sprintf() & co.  This patch replaces such sprintf()
calls with sysfs_emit() while simplifying the open code in
list_show().

Link: https://lore.kernel.org/r/20220801165639.26030-4-tiwai@suse.de


Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent 0980bb1f

sound/core/control_led.c

+12 −17
Original line number Diff line number Diff line
@@ -405,7 +405,7 @@ static ssize_t mode_show(struct device *dev, 
	case MODE_ON:		str = "on"; break;

	case MODE_OFF:		str = "off"; break;

	}

	return sprintf(buf, "%s\n", str);

	return sysfs_emit(buf, "%s\n", str);

}



static ssize_t mode_store(struct device *dev,
@@ -443,7 +443,7 @@ static ssize_t brightness_show(struct device *dev, 
{

	struct snd_ctl_led *led = container_of(dev, struct snd_ctl_led, dev);



	return sprintf(buf, "%u\n", ledtrig_audio_get(led->trigger_type));

	return sysfs_emit(buf, "%u\n", ledtrig_audio_get(led->trigger_type));

}



static DEVICE_ATTR_RW(mode);
@@ -618,8 +618,7 @@ static ssize_t list_show(struct device *dev, 
	struct snd_ctl_led_card *led_card = container_of(dev, struct snd_ctl_led_card, dev);

	struct snd_card *card;

	struct snd_ctl_led_ctl *lctl;

	char *buf2 = buf;

	size_t l;

	size_t l = 0;



	card = snd_card_ref(led_card->number);

	if (!card)
@@ -627,23 +626,19 @@ static ssize_t list_show(struct device *dev, 
	down_read(&card->controls_rwsem);

	mutex_lock(&snd_ctl_led_mutex);

	if (snd_ctl_led_card_valid[led_card->number]) {

		list_for_each_entry(lctl, &led_card->led->controls, list)

			if (lctl->card == card) {

				if (buf2 - buf > PAGE_SIZE - 16)

					break;

				if (buf2 != buf)

					*buf2++ = ' ';

				l = scnprintf(buf2, 15, "%u",

						lctl->kctl->id.numid +

							lctl->index_offset);

				buf2[l] = '\0';

				buf2 += l + 1;

		list_for_each_entry(lctl, &led_card->led->controls, list) {

			if (lctl->card != card)

				continue;

			if (l)

				l += sysfs_emit_at(buf, l, " ");

			l += sysfs_emit_at(buf, l, "%u",

					   lctl->kctl->id.numid + lctl->index_offset);

		}

	}

	mutex_unlock(&snd_ctl_led_mutex);

	up_read(&card->controls_rwsem);

	snd_card_unref(card);

	return buf2 - buf;

	return l;

}



static DEVICE_ATTR_WO(attach);