1 files changed, 326 insertions, 0 deletions
diff --git a/sound/pci/echoaudio/midi.c b/sound/pci/echoaudio/midi.c
new file mode 100644
index 000000000..6045a115c
--- /dev/null
+++ b/sound/pci/echoaudio/midi.c
@@ -0,0 +1,326 @@
+/****************************************************************************
+
+   Copyright Echo Digital Audio Corporation (c) 1998 - 2004
+   All rights reserved
+   www.echoaudio.com
+
+   This file is part of Echo Digital Audio's generic driver library.
+
+   Echo Digital Audio's generic driver library is free software;
+   you can redistribute it and/or modify it under the terms of
+   the GNU General Public License as published by the Free Software
+   Foundation.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+   MA  02111-1307, USA.
+
+   *************************************************************************
+
+ Translation from C++ and adaptation for use in ALSA-Driver
+ were made by Giuliano Pochini <pochini@shiny.it>
+
+****************************************************************************/
+
+
+/******************************************************************************
+	MIDI lowlevel code
+******************************************************************************/
+
+/* Start and stop Midi input */
+static int enable_midi_input(struct echoaudio *chip, char enable)
+{
+	dev_dbg(chip->card->dev, "enable_midi_input(%d)\n", enable);
+
+	if (wait_handshake(chip))
+		return -EIO;
+
+	if (enable) {
+		chip->mtc_state = MIDI_IN_STATE_NORMAL;
+		chip->comm_page->flags |=
+			cpu_to_le32(DSP_FLAG_MIDI_INPUT);
+	} else
+		chip->comm_page->flags &=
+			~cpu_to_le32(DSP_FLAG_MIDI_INPUT);
+
+	clear_handshake(chip);
+	return send_vector(chip, DSP_VC_UPDATE_FLAGS);
+}
+
+
+
+/* Send a buffer full of MIDI data to the DSP
+Returns how many actually written or < 0 on error */
+static int write_midi(struct echoaudio *chip, u8 *data, int bytes)
+{
+	if (snd_BUG_ON(bytes <= 0 || bytes >= MIDI_OUT_BUFFER_SIZE))
+		return -EINVAL;
+
+	if (wait_handshake(chip))
+		return -EIO;
+
+	/* HF4 indicates that it is safe to write MIDI output data */
+	if (! (get_dsp_register(chip, CHI32_STATUS_REG) & CHI32_STATUS_REG_HF4))
+		return 0;
+
+	chip->comm_page->midi_output[0] = bytes;
+	memcpy(&chip->comm_page->midi_output[1], data, bytes);
+	chip->comm_page->midi_out_free_count = 0;
+	clear_handshake(chip);
+	send_vector(chip, DSP_VC_MIDI_WRITE);
+	dev_dbg(chip->card->dev, "write_midi: %d\n", bytes);
+	return bytes;
+}
+
+
+
+/* Run the state machine for MIDI input data
+MIDI time code sync isn't supported by this code right now, but you still need
+this state machine to parse the incoming MIDI data stream.  Every time the DSP
+sees a 0xF1 byte come in, it adds the DSP sample position to the MIDI data
+stream. The DSP sample position is represented as a 32 bit unsigned value,
+with the high 16 bits first, followed by the low 16 bits. Since these aren't
+real MIDI bytes, the following logic is needed to skip them. */
+static inline int mtc_process_data(struct echoaudio *chip, short midi_byte)
+{
+	switch (chip->mtc_state) {
+	case MIDI_IN_STATE_NORMAL:
+		if (midi_byte == 0xF1)
+			chip->mtc_state = MIDI_IN_STATE_TS_HIGH;
+		break;
+	case MIDI_IN_STATE_TS_HIGH:
+		chip->mtc_state = MIDI_IN_STATE_TS_LOW;
+		return MIDI_IN_SKIP_DATA;
+		break;
+	case MIDI_IN_STATE_TS_LOW:
+		chip->mtc_state = MIDI_IN_STATE_F1_DATA;
+		return MIDI_IN_SKIP_DATA;
+		break;
+	case MIDI_IN_STATE_F1_DATA:
+		chip->mtc_state = MIDI_IN_STATE_NORMAL;
+		break;
+	}
+	return 0;
+}
+
+
+
+/* This function is called from the IRQ handler and it reads the midi data
+from the DSP's buffer.  It returns the number of bytes received. */
+static int midi_service_irq(struct echoaudio *chip)
+{
+	short int count, midi_byte, i, received;
+
+	/* The count is at index 0, followed by actual data */
+	count = le16_to_cpu(chip->comm_page->midi_input[0]);
+
+	if (snd_BUG_ON(count >= MIDI_IN_BUFFER_SIZE))
+		return 0;
+
+	/* Get the MIDI data from the comm page */
+	i = 1;
+	received = 0;
+	for (i = 1; i <= count; i++) {
+		/* Get the MIDI byte */
+		midi_byte = le16_to_cpu(chip->comm_page->midi_input[i]);
+
+		/* Parse the incoming MIDI stream. The incoming MIDI data
+		consists of MIDI bytes and timestamps for the MIDI time code
+		0xF1 bytes. mtc_process_data() is a little state machine that
+		parses the stream. If you get MIDI_IN_SKIP_DATA back, then
+		this is a timestamp byte, not a MIDI byte, so don't store it
+		in the MIDI input buffer. */
+		if (mtc_process_data(chip, midi_byte) == MIDI_IN_SKIP_DATA)
+			continue;
+
+		chip->midi_buffer[received++] = (u8)midi_byte;
+	}
+
+	return received;
+}
+
+
+
+
+/******************************************************************************
+	MIDI interface
+******************************************************************************/
+
+static int snd_echo_midi_input_open(struct snd_rawmidi_substream *substream)
+{
+	struct echoaudio *chip = substream->rmidi->private_data;
+
+	chip->midi_in = substream;
+	return 0;
+}
+
+
+
+static void snd_echo_midi_input_trigger(struct snd_rawmidi_substream *substream,
+					int up)
+{
+	struct echoaudio *chip = substream->rmidi->private_data;
+
+	if (up != chip->midi_input_enabled) {
+		spin_lock_irq(&chip->lock);
+		enable_midi_input(chip, up);
+		spin_unlock_irq(&chip->lock);
+		chip->midi_input_enabled = up;
+	}
+}
+
+
+
+static int snd_echo_midi_input_close(struct snd_rawmidi_substream *substream)
+{
+	struct echoaudio *chip = substream->rmidi->private_data;
+
+	chip->midi_in = NULL;
+	return 0;
+}
+
+
+
+static int snd_echo_midi_output_open(struct snd_rawmidi_substream *substream)
+{
+	struct echoaudio *chip = substream->rmidi->private_data;
+
+	chip->tinuse = 0;
+	chip->midi_full = 0;
+	chip->midi_out = substream;
+	return 0;
+}
+
+
+
+static void snd_echo_midi_output_write(struct timer_list *t)
+{
+	struct echoaudio *chip = from_timer(chip, t, timer);
+	unsigned long flags;
+	int bytes, sent, time;
+	unsigned char buf[MIDI_OUT_BUFFER_SIZE - 1];
+
+	/* No interrupts are involved: we have to check at regular intervals
+	if the card's output buffer has room for new data. */
+	sent = bytes = 0;
+	spin_lock_irqsave(&chip->lock, flags);
+	chip->midi_full = 0;
+	if (!snd_rawmidi_transmit_empty(chip->midi_out)) {
+		bytes = snd_rawmidi_transmit_peek(chip->midi_out, buf,
+						  MIDI_OUT_BUFFER_SIZE - 1);
+		dev_dbg(chip->card->dev, "Try to send %d bytes...\n", bytes);
+		sent = write_midi(chip, buf, bytes);
+		if (sent < 0) {
+			dev_err(chip->card->dev,
+				"write_midi() error %d\n", sent);
+			/* retry later */
+			sent = 9000;
+			chip->midi_full = 1;
+		} else if (sent > 0) {
+			dev_dbg(chip->card->dev, "%d bytes sent\n", sent);
+			snd_rawmidi_transmit_ack(chip->midi_out, sent);
+		} else {
+			/* Buffer is full. DSP's internal buffer is 64 (128 ?)
+			bytes long. Let's wait until half of them are sent */
+			dev_dbg(chip->card->dev, "Full\n");
+			sent = 32;
+			chip->midi_full = 1;
+		}
+	}
+
+	/* We restart the timer only if there is some data left to send */
+	if (!snd_rawmidi_transmit_empty(chip->midi_out) && chip->tinuse) {
+		/* The timer will expire slightly after the data has been
+		   sent */
+		time = (sent << 3) / 25 + 1;	/* 8/25=0.32ms to send a byte */
+		mod_timer(&chip->timer, jiffies + (time * HZ + 999) / 1000);
+		dev_dbg(chip->card->dev,
+			"Timer armed(%d)\n", ((time * HZ + 999) / 1000));
+	}
+	spin_unlock_irqrestore(&chip->lock, flags);
+}
+
+
+
+static void snd_echo_midi_output_trigger(struct snd_rawmidi_substream *substream,
+					 int up)
+{
+	struct echoaudio *chip = substream->rmidi->private_data;
+
+	dev_dbg(chip->card->dev, "snd_echo_midi_output_trigger(%d)\n", up);
+	spin_lock_irq(&chip->lock);
+	if (up) {
+		if (!chip->tinuse) {
+			timer_setup(&chip->timer, snd_echo_midi_output_write,
+				    0);
+			chip->tinuse = 1;
+		}
+	} else {
+		if (chip->tinuse) {
+			chip->tinuse = 0;
+			spin_unlock_irq(&chip->lock);
+			del_timer_sync(&chip->timer);
+			dev_dbg(chip->card->dev, "Timer removed\n");
+			return;
+		}
+	}
+	spin_unlock_irq(&chip->lock);
+
+	if (up && !chip->midi_full)
+		snd_echo_midi_output_write(&chip->timer);
+}
+
+
+
+static int snd_echo_midi_output_close(struct snd_rawmidi_substream *substream)
+{
+	struct echoaudio *chip = substream->rmidi->private_data;
+
+	chip->midi_out = NULL;
+	return 0;
+}
+
+
+
+static const struct snd_rawmidi_ops snd_echo_midi_input = {
+	.open = snd_echo_midi_input_open,
+	.close = snd_echo_midi_input_close,
+	.trigger = snd_echo_midi_input_trigger,
+};
+
+static const struct snd_rawmidi_ops snd_echo_midi_output = {
+	.open = snd_echo_midi_output_open,
+	.close = snd_echo_midi_output_close,
+	.trigger = snd_echo_midi_output_trigger,
+};
+
+
+
+/* <--snd_echo_probe() */
+static int snd_echo_midi_create(struct snd_card *card,
+				struct echoaudio *chip)
+{
+	int err;
+
+	if ((err = snd_rawmidi_new(card, card->shortname, 0, 1, 1,
+				   &chip->rmidi)) < 0)
+		return err;
+
+	strcpy(chip->rmidi->name, card->shortname);
+	chip->rmidi->private_data = chip;
+
+	snd_rawmidi_set_ops(chip->rmidi, SNDRV_RAWMIDI_STREAM_INPUT,
+			    &snd_echo_midi_input);
+	snd_rawmidi_set_ops(chip->rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
+			    &snd_echo_midi_output);
+
+	chip->rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT |
+		SNDRV_RAWMIDI_INFO_INPUT | SNDRV_RAWMIDI_INFO_DUPLEX;
+	return 0;
+}