Commit 599ee329 authored Dec 29, 2014 by Lars-Peter Clausen Committed by Takashi Iwai Dec 30, 2014

ALSA: pcm: Use __ffs() instead of ffs() in snd_mask_min()



The difference between __ffs and ffs is that ffs will return a one based
index whereas __ffs will return a zero based index. Furthermore ffs will
check if the passed value is zero and return zero in that case, whereas
__ffs behavior is undefined if the passed parameter is 0.

Since we already check if the mask is 0 before calling ffs and also subtract
1 from the result __ffs is the better choice.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

parent cd9978f1

include/sound/pcm_params.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -92,7 +92,7 @@ static inline unsigned int snd_mask_min(const struct snd_mask *mask)
		int i;
		for (i = 0; i < SNDRV_MASK_SIZE; i++) {
		if (mask->bits[i])
		return ffs(mask->bits[i]) - 1 + (i << 5);
		return __ffs(mask->bits[i]) + (i << 5);
		}
		return 0;
		}