[ALSA] PCM - added back TSTAMP ioctl for PCM (for old alsa-lib binaries)

Signed-off-by: Jaroslav Kysela <perex@perex.cz>

include/sound/asound.h

@@ -443,6 +443,7 @@ enum {
 enum {
 	SNDRV_PCM_IOCTL_PVERSION = _IOR('A', 0x00, int),
 	SNDRV_PCM_IOCTL_INFO = _IOR('A', 0x01, struct snd_pcm_info),
+	SNDRV_PCM_IOCTL_TSTAMP = _IOW('A', 0x02, int),
 	SNDRV_PCM_IOCTL_TTSTAMP = _IOW('A', 0x03, int),
 	SNDRV_PCM_IOCTL_HW_REFINE = _IOWR('A', 0x10, struct snd_pcm_hw_params),
 	SNDRV_PCM_IOCTL_HW_PARAMS = _IOWR('A', 0x11, struct snd_pcm_hw_params),

sound/core/pcm_native.c

@@ -2546,6 +2546,8 @@ static int snd_pcm_common_ioctl1(struct file *file,
 		return put_user(SNDRV_PCM_VERSION, (int __user *)arg) ? -EFAULT : 0;
 	case SNDRV_PCM_IOCTL_INFO:
 		return snd_pcm_info_user(substream, arg);
+	case SNDRV_PCM_IOCTL_TSTAMP:	/* just for compatibility */
+		return 0;
 	case SNDRV_PCM_IOCTL_TTSTAMP:
 		return snd_pcm_tstamp(substream, arg);
 	case SNDRV_PCM_IOCTL_HW_REFINE: