Add IEC958 channel status helper that creates control to handle the
IEC60958 status bits.
Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxx>
---
include/sound/pcm_iec958.h | 21 ++++++++
sound/core/pcm_iec958.c | 125 +++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 146 insertions(+)
diff --git a/include/sound/pcm_iec958.h b/include/sound/pcm_iec958.h
index 0eed397..6d5e3d1 100644
--- a/include/sound/pcm_iec958.h
+++ b/include/sound/pcm_iec958.h
@@ -3,7 +3,28 @@
#include <linux/types.h>
+/**
+ * struct snd_pcm_iec958_params: IEC 60958 controls parameters
+ * @ctrl_set: control set callback
+ * This callback is optional and shall be used to set associated driver
+ * configuration. Calls under mutex protection.
+ * @iec: Mandatory pointer to iec958 structure.
+ * @pdata: Optional pointer to driver context.
+ * @mutex: Mandatory pointer to mutex
+ * Provided by driver to handle race conditions.
+ */
+struct snd_pcm_iec958_params {
+ int (*ctrl_set)(void *pdata, u8 *status);
+ struct snd_aes_iec958 *iec;
+ void *pdata;
+ struct mutex *mutex;
+};
+
int snd_pcm_create_iec958_consumer(struct snd_pcm_runtime *runtime, u8 *cs,
size_t len);
+int snd_pcm_create_iec958_ctl(struct snd_pcm *pcm, int subdevice,
+ struct snd_pcm_iec958_params *params,
+ int stream);
+const struct snd_kcontrol_new *snd_pcm_iec958_ctl_new(int stream);
#endif
diff --git a/sound/core/pcm_iec958.c b/sound/core/pcm_iec958.c
index 36b2d7a..24d6a8e 100644
--- a/sound/core/pcm_iec958.c
+++ b/sound/core/pcm_iec958.c
@@ -7,10 +7,97 @@
*/
#include <linux/export.h>
#include <linux/types.h>
+#include <linux/wait.h>
#include <sound/asoundef.h>
+#include <sound/control.h>
#include <sound/pcm.h>
#include <sound/pcm_iec958.h>
+static int snd_pcm_iec958_info(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_info *uinfo)
+{
+ uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
+ uinfo->count = 1;
+ return 0;
+}
+
+/*
+ * IEC958 channel status default controls callbacks
+ *
+ * Callbacks are protected by a mutex provided by user.
+ */
+static int snd_pcm_iec958_get(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_value *uctl)
+{
+ struct snd_pcm_iec958_params *params = snd_kcontrol_chip(kcontrol);
+ int i;
+
+ if (!params->mutex)
+ return -EINVAL;
+
+ mutex_lock(params->mutex);
+ for (i = 0; i < 5; i++)
+ uctl->value.iec958.status[i] = params->iec->status[i];
+ mutex_unlock(params->mutex);
+
+ return 0;
+}
+
+static int snd_pcm_iec958_put(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_value *uctl)
+{
+ struct snd_pcm_iec958_params *params = snd_kcontrol_chip(kcontrol);
+ int err = 0;
+ int i, updated = 0;
+
+ if (!params->mutex)
+ return -EINVAL;
+
+ mutex_lock(params->mutex);
+ for (i = 0; i < 5; i++) {
+ if (params->iec->status[i] != uctl->value.iec958.status[i])
+ updated = 1;
+ }
+
+ if (!updated)
+ goto unlock;
+
+ if (params->ctrl_set)
+ err = params->ctrl_set(params->pdata,
+ uctl->value.iec958.status);
+ if (err < 0) {
+ mutex_unlock(params->mutex);
+ return err;
+ }
+
+ for (i = 0; i < 5; i++)
+ params->iec->status[i] = uctl->value.iec958.status[i];
+
+ unlock:
+ mutex_unlock(params->mutex);
+ return updated;
+}
+
+static const struct snd_kcontrol_new iec958_ctls[] = {
+ {
+ .access = (SNDRV_CTL_ELEM_ACCESS_READWRITE |
+ SNDRV_CTL_ELEM_ACCESS_VOLATILE),
+ .iface = SNDRV_CTL_ELEM_IFACE_PCM,
+ .name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, DEFAULT),
+ .info = snd_pcm_iec958_info,
+ .get = snd_pcm_iec958_get,
+ .put = snd_pcm_iec958_put,
+ },
+ {
+ .access = (SNDRV_CTL_ELEM_ACCESS_READ |
+ SNDRV_CTL_ELEM_ACCESS_VOLATILE),
+ .iface = SNDRV_CTL_ELEM_IFACE_PCM,
+ .name = SNDRV_CTL_NAME_IEC958("", CAPTURE, DEFAULT),
+ .info = snd_pcm_iec958_info,
+ .get = snd_pcm_iec958_get,
+ },
+};
+
/**
* snd_pcm_create_iec958_consumer - create consumer format IEC958 channel status
* @runtime: pcm runtime structure with ->rate filled in
@@ -93,3 +180,41 @@ int snd_pcm_create_iec958_consumer(struct snd_pcm_runtime *runtime, u8 *cs,
return len;
}
EXPORT_SYMBOL(snd_pcm_create_iec958_consumer);
+
+/**
+ * snd_pcm_create_iec958_ctl - Add a IEC958 control associated to the pcm device
+ * @pcm: pcm device to associate to the control.
+ * @subdevice: subdevice index.Must be set to 0 if unused
+ * @iec958: snd_pcm_iec958_params structure that contains callbacks
+ * and channel status buffer.
+ * @stream: stream type SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CATURE.
+ * Returns: negative error code if something failed.
+ */
+int snd_pcm_create_iec958_ctl(struct snd_pcm *pcm, int subdevice,
+ struct snd_pcm_iec958_params *params, int stream)
+{
+ struct snd_kcontrol_new knew;
+
+ if (stream > SNDRV_PCM_STREAM_LAST)
+ return -EINVAL;
+
+ knew = iec958_ctls[stream];
+ knew.device = pcm->device;
+ knew.subdevice = subdevice;
+ return snd_ctl_add(pcm->card, snd_ctl_new1(&knew, params));
+}
+EXPORT_SYMBOL(snd_pcm_create_iec958_ctl);
+
+/**
+ * snd_pcm_iec958_ctl_new - create a IEC958 control instance from the template
+ * @stream: stream type SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CATURE.
+ * Returns: pointer to snd_kcontrol_new structure, NULL if something failed.
+ */
+const struct snd_kcontrol_new *snd_pcm_iec958_ctl_new(int stream)
+{
+ if (stream > SNDRV_PCM_STREAM_LAST)
+ return NULL;
+
+ return &iec958_ctls[stream];
+}
+EXPORT_SYMBOL(snd_pcm_iec958_ctl_new);
--
1.9.1
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