[PATCH v2 05/37] ALSA: ump: Add ioctls to inquiry UMP EP and Block info via control API

[Takashi Iwai]

It'd be convenient to have ioctls to inquiry the UMP Endpoint and UMP
Block information directly via the control API without opening the
rawmidi interface, just like SNDRV_CTL_IOCTL_RAWMIDI_INFO.

This patch extends the rawmidi ioctl handler to support those; new
ioctls, SNDRV_CTL_IOCTL_UMP_ENDPOINT_INFO and
SNDRV_CTL_IOCTL_UMP_BLOCK_INFO, return the snd_ump_endpoint and
snd_ump_block data that is specified by the device field,
respectively.

Suggested-by: Jaroslav Kysela <perex@xxxxxxxx>
Reviewed-by: Jaroslav Kysela <perex@xxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
---
 include/uapi/sound/asound.h |  2 ++
 sound/core/rawmidi.c        | 26 ++++++++++++++++++++++++++
 2 files changed, 28 insertions(+)

diff --git a/include/uapi/sound/asound.h b/include/uapi/sound/asound.h
index 1e4a21036109..5c5f41dd4001 100644
--- a/include/uapi/sound/asound.h
+++ b/include/uapi/sound/asound.h
@@ -1178,6 +1178,8 @@ struct snd_ctl_tlv {
 #define SNDRV_CTL_IOCTL_RAWMIDI_INFO	_IOWR('U', 0x41, struct snd_rawmidi_info)
 #define SNDRV_CTL_IOCTL_RAWMIDI_PREFER_SUBDEVICE _IOW('U', 0x42, int)
 #define SNDRV_CTL_IOCTL_UMP_NEXT_DEVICE	_IOWR('U', 0x43, int)
+#define SNDRV_CTL_IOCTL_UMP_ENDPOINT_INFO _IOWR('U', 0x44, struct snd_ump_endpoint_info)
+#define SNDRV_CTL_IOCTL_UMP_BLOCK_INFO	_IOWR('U', 0x45, struct snd_ump_block_info)
 #define SNDRV_CTL_IOCTL_POWER		_IOWR('U', 0xd0, int)
 #define SNDRV_CTL_IOCTL_POWER_STATE	_IOR('U', 0xd1, int)
 
diff --git a/sound/core/rawmidi.c b/sound/core/rawmidi.c
index 9936ed282b85..ffb5b58105f4 100644
--- a/sound/core/rawmidi.c
+++ b/sound/core/rawmidi.c
@@ -1043,6 +1043,28 @@ static int snd_rawmidi_next_device(struct snd_card *card, int __user *argp,
 	return 0;
 }
 
+#if IS_ENABLED(CONFIG_SND_UMP)
+/* inquiry of UMP endpoint and block info via control API */
+static int snd_rawmidi_call_ump_ioctl(struct snd_card *card, int cmd,
+				      void __user *argp)
+{
+	struct snd_ump_endpoint_info __user *info = argp;
+	struct snd_rawmidi *rmidi;
+	int device, ret;
+
+	if (get_user(device, &info->device))
+		return -EFAULT;
+	mutex_lock(&register_mutex);
+	rmidi = snd_rawmidi_search(card, device);
+	if (rmidi && rmidi->ops && rmidi->ops->ioctl)
+		ret = rmidi->ops->ioctl(rmidi, cmd, argp);
+	else
+		ret = -ENXIO;
+	mutex_unlock(&register_mutex);
+	return ret;
+}
+#endif
+
 static int snd_rawmidi_control_ioctl(struct snd_card *card,
 				     struct snd_ctl_file *control,
 				     unsigned int cmd,
@@ -1056,6 +1078,10 @@ static int snd_rawmidi_control_ioctl(struct snd_card *card,
 #if IS_ENABLED(CONFIG_SND_UMP)
 	case SNDRV_CTL_IOCTL_UMP_NEXT_DEVICE:
 		return snd_rawmidi_next_device(card, argp, true);
+	case SNDRV_CTL_IOCTL_UMP_ENDPOINT_INFO:
+		return snd_rawmidi_call_ump_ioctl(card, SNDRV_UMP_IOCTL_ENDPOINT_INFO, argp);
+	case SNDRV_CTL_IOCTL_UMP_BLOCK_INFO:
+		return snd_rawmidi_call_ump_ioctl(card, SNDRV_UMP_IOCTL_BLOCK_INFO, argp);
 #endif
 	case SNDRV_CTL_IOCTL_RAWMIDI_PREFER_SUBDEVICE:
 	{
-- 
2.35.3