--- /dev/null
+/****************************************************************************
+
+ 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)
+{
+ DE_MID(("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 |=
+ __constant_cpu_to_le32(DSP_FLAG_MIDI_INPUT);
+ } else
+ chip->comm_page->flags &=
+ ~__constant_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)
+{
+ snd_assert(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);
+ DE_MID(("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]);
+
+ snd_assert(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;
+ DE_MID(("rawmidi_iopen\n"));
+ 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;
+ DE_MID(("rawmidi_iclose\n"));
+ 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;
+ DE_MID(("rawmidi_oopen\n"));
+ return 0;
+}
+
+
+
+static void snd_echo_midi_output_write(unsigned long data)
+{
+ struct echoaudio *chip = (struct echoaudio *)data;
+ unsigned long flags;
+ int bytes, sent, time;
+ unsigned char buf[MIDI_OUT_BUFFER_SIZE - 1];
+
+ DE_MID(("snd_echo_midi_output_write\n"));
+ /* 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 (chip->midi_out && !snd_rawmidi_transmit_empty(chip->midi_out)) {
+ bytes = snd_rawmidi_transmit_peek(chip->midi_out, buf,
+ MIDI_OUT_BUFFER_SIZE - 1);
+ DE_MID(("Try to send %d bytes...\n", bytes));
+ sent = write_midi(chip, buf, bytes);
+ if (sent < 0) {
+ snd_printk(KERN_ERR "write_midi() error %d\n", sent);
+ /* retry later */
+ sent = 9000;
+ chip->midi_full = 1;
+ } else if (sent > 0) {
+ DE_MID(("%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 */
+ DE_MID(("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);
+ DE_MID(("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;
+
+ DE_MID(("snd_echo_midi_output_trigger(%d)\n", up));
+ spin_lock_irq(&chip->lock);
+ if (up) {
+ if (!chip->tinuse) {
+ init_timer(&chip->timer);
+ chip->timer.function = snd_echo_midi_output_write;
+ chip->timer.data = (unsigned long)chip;
+ chip->tinuse = 1;
+ }
+ } else {
+ if (chip->tinuse) {
+ del_timer(&chip->timer);
+ chip->tinuse = 0;
+ DE_MID(("Timer removed\n"));
+ }
+ }
+ spin_unlock_irq(&chip->lock);
+
+ if (up && !chip->midi_full)
+ snd_echo_midi_output_write((unsigned long)chip);
+}
+
+
+
+static int snd_echo_midi_output_close(struct snd_rawmidi_substream *substream)
+{
+ struct echoaudio *chip = substream->rmidi->private_data;
+
+ chip->midi_out = NULL;
+ DE_MID(("rawmidi_oclose\n"));
+ return 0;
+}
+
+
+
+static 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 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 __devinit 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;
+ DE_INIT(("MIDI ok\n"));
+ return 0;
+}
git://git.onelab.eu / linux-2.6.git / blobdiff