| /**************************************************************************** |
| |
| 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; |
| } |