[alsa-devel] [PATCH] hda-emu: Add support for channel mapping API
David Henningsson
david.henningsson at canonical.com
Mon Sep 17 11:56:37 CEST 2012
---
Hi Takashi,
I tried to make hda-emu compile with the latest changes to the HDA driver.
This is the result. It compiles, but when running any codec, I get the error
"Control element Playback Channel Map:0 already exists!".
I'm unsure whether this is a problem in the driver or in my simple copy-paste
attempt to make this work.
Can you offer some insight?
Thanks.
include/sound/asound.h | 57 +++++++++++++
include/sound/pcm.h | 58 +++++++++++++
include/sound/tlv.h | 8 ++
snd-wrapper.c | 214 ++++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 337 insertions(+)
diff --git a/include/sound/asound.h b/include/sound/asound.h
index 25e90ed..61f1440 100644
--- a/include/sound/asound.h
+++ b/include/sound/asound.h
@@ -164,3 +164,60 @@ struct snd_ctl_event {
unsigned char data8[60];
} data;
};
+
+typedef int __bitwise snd_pcm_state_t;
+#define SNDRV_PCM_STATE_OPEN ((snd_pcm_state_t) 0) /* stream is open */
+#define SNDRV_PCM_STATE_SETUP ((snd_pcm_state_t) 1) /* stream has a setup */
+#define SNDRV_PCM_STATE_PREPARED ((snd_pcm_state_t) 2) /* stream is ready to start */
+#define SNDRV_PCM_STATE_RUNNING ((snd_pcm_state_t) 3) /* stream is running */
+#define SNDRV_PCM_STATE_XRUN ((snd_pcm_state_t) 4) /* stream reached an xrun */
+#define SNDRV_PCM_STATE_DRAINING ((snd_pcm_state_t) 5) /* stream is draining */
+#define SNDRV_PCM_STATE_PAUSED ((snd_pcm_state_t) 6) /* stream is paused */
+#define SNDRV_PCM_STATE_SUSPENDED ((snd_pcm_state_t) 7) /* hardware is suspended */
+#define SNDRV_PCM_STATE_DISCONNECTED ((snd_pcm_state_t) 8) /* hardware is disconnected */
+#define SNDRV_PCM_STATE_LAST SNDRV_PCM_STATE_DISCONNECTED
+
+struct snd_pcm_mmap_status {
+ snd_pcm_state_t state; /* RO: state - SNDRV_PCM_STATE_XXXX */
+};
+
+
+/* channel positions */
+enum {
+ SNDRV_CHMAP_UNKNOWN = 0,
+ SNDRV_CHMAP_NA, /* N/A, silent */
+ SNDRV_CHMAP_MONO, /* mono stream */
+ /* this follows the alsa-lib mixer channel value + 3 */
+ SNDRV_CHMAP_FL, /* front left */
+ SNDRV_CHMAP_FR, /* front right */
+ SNDRV_CHMAP_RL, /* rear left */
+ SNDRV_CHMAP_RR, /* rear right */
+ SNDRV_CHMAP_FC, /* front center */
+ SNDRV_CHMAP_LFE, /* LFE */
+ SNDRV_CHMAP_SL, /* side left */
+ SNDRV_CHMAP_SR, /* side right */
+ SNDRV_CHMAP_RC, /* rear center */
+ /* new definitions */
+ SNDRV_CHMAP_FLC, /* front left center */
+ SNDRV_CHMAP_FRC, /* front right center */
+ SNDRV_CHMAP_RLC, /* rear left center */
+ SNDRV_CHMAP_RRC, /* rear right center */
+ SNDRV_CHMAP_FLW, /* front left wide */
+ SNDRV_CHMAP_FRW, /* front right wide */
+ SNDRV_CHMAP_FLH, /* front left high */
+ SNDRV_CHMAP_FCH, /* front center high */
+ SNDRV_CHMAP_FRH, /* front right high */
+ SNDRV_CHMAP_TC, /* top center */
+ SNDRV_CHMAP_TFL, /* top front left */
+ SNDRV_CHMAP_TFR, /* top front right */
+ SNDRV_CHMAP_TFC, /* top front center */
+ SNDRV_CHMAP_TRL, /* top rear left */
+ SNDRV_CHMAP_TRR, /* top rear right */
+ SNDRV_CHMAP_TRC, /* top rear center */
+ SNDRV_CHMAP_LAST = SNDRV_CHMAP_TRC,
+};
+
+#define SNDRV_CHMAP_POSITION_MASK 0xffff
+#define SNDRV_CHMAP_PHASE_INVERSE (0x01 << 16)
+#define SNDRV_CHMAP_DRIVER_SPEC (0x02 << 16)
+
diff --git a/include/sound/pcm.h b/include/sound/pcm.h
index f1719cb..4980c69 100644
--- a/include/sound/pcm.h
+++ b/include/sound/pcm.h
@@ -45,6 +45,8 @@ struct snd_pcm_runtime {
unsigned int info;
unsigned int rate_num;
unsigned int rate_den;
+ /* -- mmap -- */
+ struct snd_pcm_mmap_status *status;
void *private_data;
void (*private_free)(struct snd_pcm_runtime *runtime);
@@ -62,12 +64,21 @@ struct snd_pcm_substream {
struct snd_pcm_ops *ops;
/* -- runtime information -- */
struct snd_pcm_runtime *runtime;
+ /* -- next substream -- */
+ struct snd_pcm_substream *next;
void *file;
int ref_count;
+
};
struct snd_pcm_str {
+ /* -- substreams -- */
unsigned int substream_opened;
+ unsigned int substream_count;
+ struct snd_pcm_substream *substream;
+
+ struct snd_kcontrol *chmap_kctl; /* channel-mapping controls */
+
};
struct snd_pcm {
@@ -241,5 +252,52 @@ static inline int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *run,
int snd_pcm_format_width(int fmt);
+/*
+ * PCM channel-mapping control API
+ */
+/* array element of channel maps */
+struct snd_pcm_chmap_elem {
+ unsigned char channels;
+ unsigned char map[15];
+};
+
+/* channel map information; retrieved via snd_kcontrol_chip() */
+struct snd_pcm_chmap {
+ struct snd_pcm *pcm; /* assigned PCM instance */
+ int stream; /* PLAYBACK or CAPTURE */
+ struct snd_kcontrol *kctl;
+ const struct snd_pcm_chmap_elem *chmap;
+ unsigned int max_channels;
+ unsigned int channel_mask; /* optional: active channels bitmask */
+ void *private_data; /* optional: private data pointer */
+};
+
+/* get the PCM substream assigned to the given chmap info */
+static inline struct snd_pcm_substream *
+snd_pcm_chmap_substream(struct snd_pcm_chmap *info, unsigned int idx)
+{
+ struct snd_pcm_substream *s;
+ for (s = info->pcm->streams[info->stream].substream; s; s = s->next)
+ if (s->number == idx)
+ return s;
+ return NULL;
+}
+
+/* ALSA-standard channel maps (RL/RR prior to C/LFE) */
+extern const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[];
+/* Other world's standard channel maps (C/LFE prior to RL/RR) */
+extern const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[];
+
+/* bit masks to be passed to snd_pcm_chmap.channel_mask field */
+#define SND_PCM_CHMAP_MASK_24 ((1U << 2) | (1U << 4))
+#define SND_PCM_CHMAP_MASK_246 (SND_PCM_CHMAP_MASK_24 | (1U << 6))
+#define SND_PCM_CHMAP_MASK_2468 (SND_PCM_CHMAP_MASK_246 | (1U << 8))
+
+int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
+ const struct snd_pcm_chmap_elem *chmap,
+ int max_channels,
+ unsigned long private_value,
+ struct snd_pcm_chmap **info_ret);
+
#endif /* __SOUND_PCM_H */
diff --git a/include/sound/tlv.h b/include/sound/tlv.h
index 7067e2d..de36aaa 100644
--- a/include/sound/tlv.h
+++ b/include/sound/tlv.h
@@ -73,4 +73,12 @@
#define TLV_DB_GAIN_MUTE -9999999
+/*
+ * channel-mapping TLV items
+ * TLV length must match with num_channels
+ */
+#define SNDRV_CTL_TLVT_CHMAP_FIXED 0x101 /* fixed channel position */
+#define SNDRV_CTL_TLVT_CHMAP_VAR 0x102 /* channels freely swappable */
+#define SNDRV_CTL_TLVT_CHMAP_PAIRED 0x103 /* pair-wise swappable */
+
#endif /* __SOUND_TLV_H */
diff --git a/snd-wrapper.c b/snd-wrapper.c
index aaa2467..7716e67 100644
--- a/snd-wrapper.c
+++ b/snd-wrapper.c
@@ -257,3 +257,217 @@ void mylock_unlock(int *lock, const char *file, int line)
break;
}
}
+
+/*
+ * standard channel mapping helpers
+ */
+#include <sound/tlv.h>
+
+/* default channel maps for multi-channel playbacks, up to 8 channels */
+const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[] = {
+ { .channels = 1,
+ .map = { SNDRV_CHMAP_MONO } },
+ { .channels = 2,
+ .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
+ { .channels = 4,
+ .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
+ SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
+ { .channels = 6,
+ .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
+ SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
+ SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE } },
+ { .channels = 8,
+ .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
+ SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
+ SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
+ SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
+ { }
+};
+EXPORT_SYMBOL_GPL(snd_pcm_std_chmaps);
+
+/* alternative channel maps with CLFE <-> surround swapped for 6/8 channels */
+const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[] = {
+ { .channels = 1,
+ .map = { SNDRV_CHMAP_MONO } },
+ { .channels = 2,
+ .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
+ { .channels = 4,
+ .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
+ SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
+ { .channels = 6,
+ .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
+ SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
+ SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
+ { .channels = 8,
+ .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
+ SNDRV_CHMAP_FC, SNDRV_CHMAP_LFE,
+ SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
+ SNDRV_CHMAP_SL, SNDRV_CHMAP_SR } },
+ { }
+};
+EXPORT_SYMBOL_GPL(snd_pcm_alt_chmaps);
+
+static bool valid_chmap_channels(const struct snd_pcm_chmap *info, int ch)
+{
+ if (ch > info->max_channels)
+ return false;
+ return !info->channel_mask || (info->channel_mask & (1U << ch));
+}
+
+static int pcm_chmap_ctl_info(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_info *uinfo)
+{
+ struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
+
+ uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+ uinfo->count = 0;
+ uinfo->count = info->max_channels;
+ uinfo->value.integer.min = 0;
+ uinfo->value.integer.max = SNDRV_CHMAP_LAST;
+ return 0;
+}
+
+/* get callback for channel map ctl element
+ * stores the channel position firstly matching with the current channels
+ */
+static int pcm_chmap_ctl_get(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
+ unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
+ struct snd_pcm_substream *substream;
+ const struct snd_pcm_chmap_elem *map;
+
+ if (snd_BUG_ON(!info->chmap))
+ return -EINVAL;
+ substream = snd_pcm_chmap_substream(info, idx);
+ if (!substream)
+ return -ENODEV;
+ memset(ucontrol->value.integer.value, 0,
+ sizeof(ucontrol->value.integer.value));
+ if (!substream->runtime)
+ return 0; /* no channels set */
+ for (map = info->chmap; map->channels; map++) {
+ int i;
+ if (map->channels == substream->runtime->channels &&
+ valid_chmap_channels(info, map->channels)) {
+ for (i = 0; i < map->channels; i++)
+ ucontrol->value.integer.value[i] = map->map[i];
+ return 0;
+ }
+ }
+ return -EINVAL;
+}
+
+/* tlv callback for channel map ctl element
+ * expands the pre-defined channel maps in a form of TLV
+ */
+static int pcm_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
+ unsigned int size, unsigned int __user *tlv)
+{
+ struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
+ const struct snd_pcm_chmap_elem *map;
+ unsigned int __user *dst;
+ int c, count = 0;
+
+ if (snd_BUG_ON(!info->chmap))
+ return -EINVAL;
+ if (size < 8)
+ return -ENOMEM;
+ if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
+ return -EFAULT;
+ size -= 8;
+ dst = tlv + 2;
+ for (map = info->chmap; map->channels; map++) {
+ int chs_bytes = map->channels * 4;
+ if (!valid_chmap_channels(info, map->channels))
+ continue;
+ if (size < 8)
+ return -ENOMEM;
+ if (put_user(SNDRV_CTL_TLVT_CHMAP_FIXED, dst) ||
+ put_user(chs_bytes, dst + 1))
+ return -EFAULT;
+ dst += 2;
+ size -= 8;
+ count += 8;
+ if (size < chs_bytes)
+ return -ENOMEM;
+ size -= chs_bytes;
+ count += chs_bytes;
+ for (c = 0; c < map->channels; c++) {
+ if (put_user(map->map[c], dst))
+ return -EFAULT;
+ dst++;
+ }
+ }
+ if (put_user(count, tlv + 1))
+ return -EFAULT;
+ return 0;
+}
+
+static void pcm_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
+{
+ struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
+ info->pcm->streams[info->stream].chmap_kctl = NULL;
+ kfree(info);
+}
+
+/**
+ * snd_pcm_add_chmap_ctls - create channel-mapping control elements
+ * @pcm: the assigned PCM instance
+ * @stream: stream direction
+ * @chmap: channel map elements (for query)
+ * @max_channels: the max number of channels for the stream
+ * @private_value: the value passed to each kcontrol's private_value field
+ * @info_ret: store struct snd_pcm_chmap instance if non-NULL
+ *
+ * Create channel-mapping control elements assigned to the given PCM stream(s).
+ * Returns zero if succeed, or a negative error value.
+ */
+int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
+ const struct snd_pcm_chmap_elem *chmap,
+ int max_channels,
+ unsigned long private_value,
+ struct snd_pcm_chmap **info_ret)
+{
+ struct snd_pcm_chmap *info;
+ struct snd_kcontrol_new knew = {
+ .iface = SNDRV_CTL_ELEM_IFACE_PCM,
+ .access = SNDRV_CTL_ELEM_ACCESS_READ |
+ SNDRV_CTL_ELEM_ACCESS_TLV_READ |
+ SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
+ .info = pcm_chmap_ctl_info,
+ .get = pcm_chmap_ctl_get,
+ .tlv.c = pcm_chmap_ctl_tlv,
+ };
+ int err;
+
+ info = kzalloc(sizeof(*info), GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+ info->pcm = pcm;
+ info->stream = stream;
+ info->chmap = chmap;
+ info->max_channels = max_channels;
+ if (stream == SNDRV_PCM_STREAM_PLAYBACK)
+ knew.name = "Playback Channel Map";
+ else
+ knew.name = "Capture Channel Map";
+ knew.device = pcm->device;
+ knew.count = pcm->streams[stream].substream_count;
+ knew.private_value = private_value;
+ info->kctl = snd_ctl_new1(&knew, info);
+ if (!info->kctl) {
+ kfree(info);
+ return -ENOMEM;
+ }
+ info->kctl->private_free = pcm_chmap_ctl_private_free;
+ err = snd_ctl_add(pcm->card, info->kctl);
+ if (err < 0)
+ return err;
+ pcm->streams[stream].chmap_kctl = info->kctl;
+ if (info_ret)
+ *info_ret = info;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(snd_pcm_add_chmap_ctls);
--
1.7.9.5
More information about the Alsa-devel
mailing list