2023-09-27 16:44:32

by Ivan Orlov

Subject: [PATCH 2/2] ALSA: aloop: Add control element for getting the access mode

Add new control element 'PCM Slave Access Mode' which shows the access
mode (interleaved/non-interleaved) for the PCM playing device. Add
corresponding control change notification calls.

Signed-off-by: Ivan Orlov <[email protected]>
---
sound/drivers/aloop.c | 45 ++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 44 insertions(+), 1 deletion(-)

diff --git a/sound/drivers/aloop.c b/sound/drivers/aloop.c
index ab116b1fed96..e87dc67f33c6 100644
--- a/sound/drivers/aloop.c
+++ b/sound/drivers/aloop.c
@@ -119,11 +119,13 @@ struct loopback_setup {
unsigned int rate_shift;
snd_pcm_format_t format;
unsigned int rate;
+ snd_pcm_access_t access;
unsigned int channels;
struct snd_ctl_elem_id active_id;
struct snd_ctl_elem_id format_id;
struct snd_ctl_elem_id rate_id;
struct snd_ctl_elem_id channels_id;
+ struct snd_ctl_elem_id access_id;
};

struct loopback {
@@ -367,6 +369,11 @@ static int loopback_check_format(struct loopback_cable *cable, int stream)
&setup->channels_id);
setup->channels = runtime->channels;
}
+ if (setup->access != runtime->access) {
+ snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
+ &setup->access_id);
+ setup->access = runtime->access;
+ }
}
return 0;
}
@@ -1520,6 +1527,30 @@ static int loopback_channels_get(struct snd_kcontrol *kcontrol,
return 0;
}

+static int loopback_access_info(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_info *uinfo)
+{
+ const char * const texts[] = {"Interleaved", "Non-interleaved"};
+
+ return snd_ctl_enum_info(uinfo, 1, ARRAY_SIZE(texts), texts);
+}
+
+static int loopback_access_get(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct loopback *loopback = snd_kcontrol_chip(kcontrol);
+ snd_pcm_access_t access;
+
+ mutex_lock(&loopback->cable_lock);
+ access = loopback->setup[kcontrol->id.subdevice][kcontrol->id.device].access;
+
+ ucontrol->value.enumerated.item[0] = access == SNDRV_PCM_ACCESS_RW_NONINTERLEAVED ||
+ access == SNDRV_PCM_ACCESS_MMAP_NONINTERLEAVED;
+
+ mutex_unlock(&loopback->cable_lock);
+ return 0;
+}
+
static const struct snd_kcontrol_new loopback_controls[] = {
{
.iface = SNDRV_CTL_ELEM_IFACE_PCM,
@@ -1566,7 +1597,15 @@ static const struct snd_kcontrol_new loopback_controls[] = {
.name = "PCM Slave Channels",
.info = loopback_channels_info,
.get = loopback_channels_get
-}
+},
+#define ACCESS_IDX 6
+{
+ .access = SNDRV_CTL_ELEM_ACCESS_READ,
+ .iface = SNDRV_CTL_ELEM_IFACE_PCM,
+ .name = "PCM Slave Access Mode",
+ .info = loopback_access_info,
+ .get = loopback_access_get,
+},
};

static int loopback_mixer_new(struct loopback *loopback, int notify)
@@ -1587,6 +1626,7 @@ static int loopback_mixer_new(struct loopback *loopback, int notify)
setup->notify = notify;
setup->rate_shift = NO_PITCH;
setup->format = SNDRV_PCM_FORMAT_S16_LE;
+ setup->access = SNDRV_PCM_ACCESS_RW_INTERLEAVED;
setup->rate = 48000;
setup->channels = 2;
for (idx = 0; idx < ARRAY_SIZE(loopback_controls);
@@ -1618,6 +1658,9 @@ static int loopback_mixer_new(struct loopback *loopback, int notify)
case CHANNELS_IDX:
setup->channels_id = kctl->id;
break;
+ case ACCESS_IDX:
+ setup->access_id = kctl->id;
+ break;
default:
break;
}
--
2.34.1

2023-10-05 16:09:12

by Jaroslav Kysela

Subject: Re: [PATCH 2/2] ALSA: aloop: Add control element for getting the access mode

On 27. 09. 23 13:35, Ivan Orlov wrote:
> Add new control element 'PCM Slave Access Mode' which shows the access
> mode (interleaved/non-interleaved) for the PCM playing device. Add
> corresponding control change notification calls.
>
> Signed-off-by: Ivan Orlov <[email protected]>

Reviewed-by: Jaroslav Kysela <[email protected]>

Jaroslav

--
Jaroslav Kysela <[email protected]>
Linux Sound Maintainer; ALSA Project; Red Hat, Inc.