ALSA: ump: Redirect rawmidi substream access via own helpers

This is a code refactoring for abstracting the rawmidi access to the
UMP's own helpers.  It's a preliminary work for the later code
refactoring of the UMP layer.

Until now, we access to the rawmidi substream directly from the
driver via rawmidi access helpers, but after this change, the driver
is supposed to access via the newly introduced snd_ump_ops and
receive/transmit via snd_ump_receive() and snd_ump_transmit() helpers.
As of this commit, those are merely wrappers for the rawmidi
substream, and no much function change is seen here.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20230523075358.9672-14-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 111 insertions, 0 deletions

diff --git a/sound/core/ump.c b/sound/core/ump.c
index 651cd3752719..46ec297a786c 100644
--- a/sound/core/ump.c
+++ b/sound/core/ump.c
@@ -23,6 +23,11 @@ static long snd_ump_ioctl(struct snd_rawmidi *rmidi, unsigned int cmd,
 			  void __user *argp);
 static void snd_ump_proc_read(struct snd_info_entry *entry,
 			      struct snd_info_buffer *buffer);
+static int snd_ump_rawmidi_open(struct snd_rawmidi_substream *substream);
+static int snd_ump_rawmidi_close(struct snd_rawmidi_substream *substream);
+static void snd_ump_rawmidi_trigger(struct snd_rawmidi_substream *substream,
+				    int up);
+static void snd_ump_rawmidi_drain(struct snd_rawmidi_substream *substream);
 
 static const struct snd_rawmidi_global_ops snd_ump_rawmidi_ops = {
 	.dev_register = snd_ump_dev_register,
@@ -31,6 +36,19 @@ static const struct snd_rawmidi_global_ops snd_ump_rawmidi_ops = {
 	.proc_read = snd_ump_proc_read,
 };
 
+static const struct snd_rawmidi_ops snd_ump_rawmidi_input_ops = {
+	.open = snd_ump_rawmidi_open,
+	.close = snd_ump_rawmidi_close,
+	.trigger = snd_ump_rawmidi_trigger,
+};
+
+static const struct snd_rawmidi_ops snd_ump_rawmidi_output_ops = {
+	.open = snd_ump_rawmidi_open,
+	.close = snd_ump_rawmidi_close,
+	.trigger = snd_ump_rawmidi_trigger,
+	.drain = snd_ump_rawmidi_drain,
+};
+
 static void snd_ump_endpoint_free(struct snd_rawmidi *rmidi)
 {
 	struct snd_ump_endpoint *ump = rawmidi_to_ump(rmidi);
@@ -104,6 +122,12 @@ int snd_ump_endpoint_new(struct snd_card *card, char *id, int device,
 
 	ump->core.private_free = snd_ump_endpoint_free;
 	ump->core.ops = &snd_ump_rawmidi_ops;
+	if (input)
+		snd_rawmidi_set_ops(&ump->core, SNDRV_RAWMIDI_STREAM_INPUT,
+				    &snd_ump_rawmidi_input_ops);
+	if (output)
+		snd_rawmidi_set_ops(&ump->core, SNDRV_RAWMIDI_STREAM_OUTPUT,
+				    &snd_ump_rawmidi_output_ops);
 
 	ump_dbg(ump, "Created a UMP EP #%d (%s)\n", device, id);
 	*ump_ret = ump;
@@ -137,6 +161,93 @@ snd_ump_get_block(struct snd_ump_endpoint *ump, unsigned char id)
 	return NULL;
 }
 
+/*
+ * rawmidi ops for UMP endpoint
+ */
+static int snd_ump_rawmidi_open(struct snd_rawmidi_substream *substream)
+{
+	struct snd_ump_endpoint *ump = rawmidi_to_ump(substream->rmidi);
+	int dir = substream->stream;
+	int err;
+
+	if (ump->substreams[dir])
+		return -EBUSY;
+	err = ump->ops->open(ump, dir);
+	if (err < 0)
+		return err;
+	ump->substreams[dir] = substream;
+	return 0;
+}
+
+static int snd_ump_rawmidi_close(struct snd_rawmidi_substream *substream)
+{
+	struct snd_ump_endpoint *ump = rawmidi_to_ump(substream->rmidi);
+	int dir = substream->stream;
+
+	ump->substreams[dir] = NULL;
+	ump->ops->close(ump, dir);
+	return 0;
+}
+
+static void snd_ump_rawmidi_trigger(struct snd_rawmidi_substream *substream,
+				    int up)
+{
+	struct snd_ump_endpoint *ump = rawmidi_to_ump(substream->rmidi);
+	int dir = substream->stream;
+
+	ump->ops->trigger(ump, dir, up);
+}
+
+static void snd_ump_rawmidi_drain(struct snd_rawmidi_substream *substream)
+{
+	struct snd_ump_endpoint *ump = rawmidi_to_ump(substream->rmidi);
+
+	if (ump->ops->drain)
+		ump->ops->drain(ump, SNDRV_RAWMIDI_STREAM_OUTPUT);
+}
+
+/**
+ * snd_ump_receive - transfer UMP packets from the device
+ * @ump: the UMP endpoint
+ * @buffer: the buffer pointer to transfer
+ * @count: byte size to transfer
+ *
+ * Called from the driver to submit the received UMP packets from the device
+ * to user-space.  It's essentially a wrapper of rawmidi_receive().
+ * The data to receive is in CPU-native endianness.
+ */
+int snd_ump_receive(struct snd_ump_endpoint *ump, const u32 *buffer, int count)
+{
+	struct snd_rawmidi_substream *substream =
+		ump->substreams[SNDRV_RAWMIDI_STREAM_INPUT];
+
+	if (!substream)
+		return 0;
+	return snd_rawmidi_receive(substream, (const char *)buffer, count);
+}
+EXPORT_SYMBOL_GPL(snd_ump_receive);
+
+/**
+ * snd_ump_transmit - transmit UMP packets
+ * @ump: the UMP endpoint
+ * @buffer: the buffer pointer to transfer
+ * @count: byte size to transfer
+ *
+ * Called from the driver to obtain the UMP packets from user-space to the
+ * device.  It's essentially a wrapper of rawmidi_transmit().
+ * The data to transmit is in CPU-native endianness.
+ */
+int snd_ump_transmit(struct snd_ump_endpoint *ump, u32 *buffer, int count)
+{
+	struct snd_rawmidi_substream *substream =
+		ump->substreams[SNDRV_RAWMIDI_STREAM_OUTPUT];
+
+	if (!substream)
+		return -ENODEV;
+	return snd_rawmidi_transmit(substream, (char *)buffer, count);
+}
+EXPORT_SYMBOL_GPL(snd_ump_transmit);
+
 /**
  * snd_ump_block_new - Create a UMP block
  * @ump: UMP object