[alsa-lib,4/8] control: Add UMP device query support

Commit Message

Takashi Iwai May 20, 2023, 7 a.m. UTC

Add a function to query the next available UMP device via control
interface, just like the existing one for rawmidi.  As the UMP rawmidi
is compatible with the standard rawmidi, no extra helper for the
rawmidi_info is present.  Ditto for the preferred subdevice, too.

Signed-off-by: Takashi Iwai <[e-mail]>
---
 include/control.h           |  1 +
 src/control/control.c       | 14 ++++++++++++++
 src/control/control_hw.c    |  9 +++++++++
 src/control/control_local.h |  1 +
 4 files changed, 25 insertions(+)

Patch

diff --git a/include/control.h b/include/control.h
index d0c40d2fa32b..a2439d78057a 100644
--- a/include/control.h
+++ b/include/control.h
@@ -417,6 +417,7 @@  int snd_ctl_pcm_prefer_subdevice(snd_ctl_t *ctl, int subdev);
 int snd_ctl_rawmidi_next_device(snd_ctl_t *ctl, int * device);
 int snd_ctl_rawmidi_info(snd_ctl_t *ctl, snd_rawmidi_info_t * info);
 int snd_ctl_rawmidi_prefer_subdevice(snd_ctl_t *ctl, int subdev);
+int snd_ctl_ump_next_device(snd_ctl_t *ctl, int *device);
 #endif
 int snd_ctl_set_power_state(snd_ctl_t *ctl, unsigned int state);
 int snd_ctl_get_power_state(snd_ctl_t *ctl, unsigned int *state);
diff --git a/src/control/control.c b/src/control/control.c
index c4ca74ec5497..615a66906414 100644
--- a/src/control/control.c
+++ b/src/control/control.c
@@ -1267,6 +1267,20 @@  int snd_ctl_rawmidi_prefer_subdevice(snd_ctl_t *ctl, int subdev)
 	return ctl->ops->rawmidi_prefer_subdevice(ctl, subdev);
 }
 
+/**
+ * \brief Get next UMP device number
+ * \param ctl CTL handle
+ * \param device current device on entry and next device on return
+ * \return 0 on success otherwise a negative error code
+ */
+int snd_ctl_ump_next_device(snd_ctl_t *ctl, int *device)
+{
+	assert(ctl && device);
+	if (ctl->ops->ump_next_device)
+		return ctl->ops->ump_next_device(ctl, device);
+	return -ENXIO;
+}
+
 /**
  * \brief Set Power State to given SND_CTL_POWER_* value and do the power management
  * \param ctl CTL handle
diff --git a/src/control/control_hw.c b/src/control/control_hw.c
index 02636910c809..ffb6f17325a7 100644
--- a/src/control/control_hw.c
+++ b/src/control/control_hw.c
@@ -325,6 +325,14 @@  static int snd_ctl_hw_rawmidi_prefer_subdevice(snd_ctl_t *handle, int subdev)
 	return 0;
 }
 
+static int snd_ctl_hw_ump_next_device(snd_ctl_t *handle, int *device)
+{
+	snd_ctl_hw_t *hw = handle->private_data;
+	if (ioctl(hw->fd, SNDRV_CTL_IOCTL_UMP_NEXT_DEVICE, device) < 0)
+		return -errno;
+	return 0;
+}
+
 static int snd_ctl_hw_set_power_state(snd_ctl_t *handle, unsigned int state)
 {
 	snd_ctl_hw_t *hw = handle->private_data;
@@ -379,6 +387,7 @@  static const snd_ctl_ops_t snd_ctl_hw_ops = {
 	.rawmidi_next_device = snd_ctl_hw_rawmidi_next_device,
 	.rawmidi_info = snd_ctl_hw_rawmidi_info,
 	.rawmidi_prefer_subdevice = snd_ctl_hw_rawmidi_prefer_subdevice,
+	.ump_next_device = snd_ctl_hw_ump_next_device,
 	.set_power_state = snd_ctl_hw_set_power_state,
 	.get_power_state = snd_ctl_hw_get_power_state,
 	.read = snd_ctl_hw_read,
diff --git a/src/control/control_local.h b/src/control/control_local.h
index b84dc4291c29..aa05bac84913 100644
--- a/src/control/control_local.h
+++ b/src/control/control_local.h
@@ -47,6 +47,7 @@  typedef struct _snd_ctl_ops {
 	int (*rawmidi_next_device)(snd_ctl_t *handle, int *device);
 	int (*rawmidi_info)(snd_ctl_t *handle, snd_rawmidi_info_t * info);
 	int (*rawmidi_prefer_subdevice)(snd_ctl_t *handle, int subdev);
+	int (*ump_next_device)(snd_ctl_t *handle, int *device);
 	int (*set_power_state)(snd_ctl_t *handle, unsigned int state);
 	int (*get_power_state)(snd_ctl_t *handle, unsigned int *state);
 	int (*read)(snd_ctl_t *handle, snd_ctl_event_t *event);