Add IEC958 channel status helper that creates control to handle the IEC60958 status bits.
Signed-off-by: Arnaud Pouliquen arnaud.pouliquen@st.com --- 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);