mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 19:29:37 +00:00
375 lines
10 KiB
C
375 lines
10 KiB
C
![]() |
// SPDX-License-Identifier: GPL-2.0-or-later
|
||
|
/*
|
||
|
* serial-generic.c
|
||
|
* Copyright (c) by Daniel Kaehn <kaehndan@gmail.com
|
||
|
* Based on serial-u16550.c by Jaroslav Kysela <perex@perex.cz>,
|
||
|
* Isaku Yamahata <yamahata@private.email.ne.jp>,
|
||
|
* George Hansper <ghansper@apana.org.au>,
|
||
|
* Hannu Savolainen
|
||
|
*
|
||
|
* Generic serial MIDI driver using the serdev serial bus API for hardware interaction
|
||
|
*/
|
||
|
|
||
|
#include <linux/err.h>
|
||
|
#include <linux/init.h>
|
||
|
#include <linux/interrupt.h>
|
||
|
#include <linux/io.h>
|
||
|
#include <linux/ioport.h>
|
||
|
#include <linux/module.h>
|
||
|
#include <linux/of_device.h>
|
||
|
#include <linux/serdev.h>
|
||
|
#include <linux/serial_reg.h>
|
||
|
#include <linux/slab.h>
|
||
|
#include <linux/dev_printk.h>
|
||
|
|
||
|
#include <sound/core.h>
|
||
|
#include <sound/rawmidi.h>
|
||
|
#include <sound/initval.h>
|
||
|
|
||
|
MODULE_DESCRIPTION("Generic serial MIDI driver");
|
||
|
MODULE_LICENSE("GPL");
|
||
|
|
||
|
#define SERIAL_MODE_INPUT_OPEN 1
|
||
|
#define SERIAL_MODE_OUTPUT_OPEN 2
|
||
|
#define SERIAL_MODE_INPUT_TRIGGERED 3
|
||
|
#define SERIAL_MODE_OUTPUT_TRIGGERED 4
|
||
|
|
||
|
#define SERIAL_TX_STATE_ACTIVE 1
|
||
|
#define SERIAL_TX_STATE_WAKEUP 2
|
||
|
|
||
|
struct snd_serial_generic {
|
||
|
struct serdev_device *serdev;
|
||
|
|
||
|
struct snd_card *card;
|
||
|
struct snd_rawmidi *rmidi;
|
||
|
struct snd_rawmidi_substream *midi_output;
|
||
|
struct snd_rawmidi_substream *midi_input;
|
||
|
|
||
|
unsigned int baudrate;
|
||
|
|
||
|
unsigned long filemode; /* open status of file */
|
||
|
struct work_struct tx_work;
|
||
|
unsigned long tx_state;
|
||
|
|
||
|
};
|
||
|
|
||
|
static void snd_serial_generic_tx_wakeup(struct snd_serial_generic *drvdata)
|
||
|
{
|
||
|
if (test_and_set_bit(SERIAL_TX_STATE_ACTIVE, &drvdata->tx_state))
|
||
|
set_bit(SERIAL_TX_STATE_WAKEUP, &drvdata->tx_state);
|
||
|
|
||
|
schedule_work(&drvdata->tx_work);
|
||
|
}
|
||
|
|
||
|
#define INTERNAL_BUF_SIZE 256
|
||
|
|
||
|
static void snd_serial_generic_tx_work(struct work_struct *work)
|
||
|
{
|
||
|
static char buf[INTERNAL_BUF_SIZE];
|
||
|
int num_bytes;
|
||
|
struct snd_serial_generic *drvdata = container_of(work, struct snd_serial_generic,
|
||
|
tx_work);
|
||
|
struct snd_rawmidi_substream *substream = drvdata->midi_output;
|
||
|
|
||
|
clear_bit(SERIAL_TX_STATE_WAKEUP, &drvdata->tx_state);
|
||
|
|
||
|
while (!snd_rawmidi_transmit_empty(substream)) {
|
||
|
|
||
|
if (!test_bit(SERIAL_MODE_OUTPUT_OPEN, &drvdata->filemode))
|
||
|
break;
|
||
|
|
||
|
num_bytes = snd_rawmidi_transmit_peek(substream, buf, INTERNAL_BUF_SIZE);
|
||
|
num_bytes = serdev_device_write_buf(drvdata->serdev, buf, num_bytes);
|
||
|
|
||
|
if (!num_bytes)
|
||
|
break;
|
||
|
|
||
|
snd_rawmidi_transmit_ack(substream, num_bytes);
|
||
|
|
||
|
if (!test_bit(SERIAL_TX_STATE_WAKEUP, &drvdata->tx_state))
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
clear_bit(SERIAL_TX_STATE_ACTIVE, &drvdata->tx_state);
|
||
|
}
|
||
|
|
||
|
static void snd_serial_generic_write_wakeup(struct serdev_device *serdev)
|
||
|
{
|
||
|
struct snd_serial_generic *drvdata = serdev_device_get_drvdata(serdev);
|
||
|
|
||
|
snd_serial_generic_tx_wakeup(drvdata);
|
||
|
}
|
||
|
|
||
|
static int snd_serial_generic_receive_buf(struct serdev_device *serdev,
|
||
|
const unsigned char *buf, size_t count)
|
||
|
{
|
||
|
int ret;
|
||
|
struct snd_serial_generic *drvdata = serdev_device_get_drvdata(serdev);
|
||
|
|
||
|
if (!test_bit(SERIAL_MODE_INPUT_OPEN, &drvdata->filemode))
|
||
|
return 0;
|
||
|
|
||
|
ret = snd_rawmidi_receive(drvdata->midi_input, buf, count);
|
||
|
return ret < 0 ? 0 : ret;
|
||
|
}
|
||
|
|
||
|
static const struct serdev_device_ops snd_serial_generic_serdev_device_ops = {
|
||
|
.receive_buf = snd_serial_generic_receive_buf,
|
||
|
.write_wakeup = snd_serial_generic_write_wakeup
|
||
|
};
|
||
|
|
||
|
static int snd_serial_generic_ensure_serdev_open(struct snd_serial_generic *drvdata)
|
||
|
{
|
||
|
int err;
|
||
|
unsigned int actual_baud;
|
||
|
|
||
|
if (drvdata->filemode)
|
||
|
return 0;
|
||
|
|
||
|
dev_dbg(drvdata->card->dev, "Opening serial port for card %s\n",
|
||
|
drvdata->card->shortname);
|
||
|
err = serdev_device_open(drvdata->serdev);
|
||
|
if (err < 0)
|
||
|
return err;
|
||
|
|
||
|
actual_baud = serdev_device_set_baudrate(drvdata->serdev,
|
||
|
drvdata->baudrate);
|
||
|
if (actual_baud != drvdata->baudrate) {
|
||
|
dev_warn(drvdata->card->dev, "requested %d baud for card %s but it was actually set to %d\n",
|
||
|
drvdata->baudrate, drvdata->card->shortname, actual_baud);
|
||
|
}
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int snd_serial_generic_input_open(struct snd_rawmidi_substream *substream)
|
||
|
{
|
||
|
int err;
|
||
|
struct snd_serial_generic *drvdata = substream->rmidi->card->private_data;
|
||
|
|
||
|
dev_dbg(drvdata->card->dev, "Opening input for card %s\n",
|
||
|
drvdata->card->shortname);
|
||
|
|
||
|
err = snd_serial_generic_ensure_serdev_open(drvdata);
|
||
|
if (err < 0)
|
||
|
return err;
|
||
|
|
||
|
set_bit(SERIAL_MODE_INPUT_OPEN, &drvdata->filemode);
|
||
|
drvdata->midi_input = substream;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int snd_serial_generic_input_close(struct snd_rawmidi_substream *substream)
|
||
|
{
|
||
|
struct snd_serial_generic *drvdata = substream->rmidi->card->private_data;
|
||
|
|
||
|
dev_dbg(drvdata->card->dev, "Closing input for card %s\n",
|
||
|
drvdata->card->shortname);
|
||
|
|
||
|
clear_bit(SERIAL_MODE_INPUT_OPEN, &drvdata->filemode);
|
||
|
clear_bit(SERIAL_MODE_INPUT_TRIGGERED, &drvdata->filemode);
|
||
|
|
||
|
drvdata->midi_input = NULL;
|
||
|
|
||
|
if (!drvdata->filemode)
|
||
|
serdev_device_close(drvdata->serdev);
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static void snd_serial_generic_input_trigger(struct snd_rawmidi_substream *substream,
|
||
|
int up)
|
||
|
{
|
||
|
struct snd_serial_generic *drvdata = substream->rmidi->card->private_data;
|
||
|
|
||
|
if (up)
|
||
|
set_bit(SERIAL_MODE_INPUT_TRIGGERED, &drvdata->filemode);
|
||
|
else
|
||
|
clear_bit(SERIAL_MODE_INPUT_TRIGGERED, &drvdata->filemode);
|
||
|
}
|
||
|
|
||
|
static int snd_serial_generic_output_open(struct snd_rawmidi_substream *substream)
|
||
|
{
|
||
|
struct snd_serial_generic *drvdata = substream->rmidi->card->private_data;
|
||
|
int err;
|
||
|
|
||
|
dev_dbg(drvdata->card->dev, "Opening output for card %s\n",
|
||
|
drvdata->card->shortname);
|
||
|
|
||
|
err = snd_serial_generic_ensure_serdev_open(drvdata);
|
||
|
if (err < 0)
|
||
|
return err;
|
||
|
|
||
|
set_bit(SERIAL_MODE_OUTPUT_OPEN, &drvdata->filemode);
|
||
|
|
||
|
drvdata->midi_output = substream;
|
||
|
return 0;
|
||
|
};
|
||
|
|
||
|
static int snd_serial_generic_output_close(struct snd_rawmidi_substream *substream)
|
||
|
{
|
||
|
struct snd_serial_generic *drvdata = substream->rmidi->card->private_data;
|
||
|
|
||
|
dev_dbg(drvdata->card->dev, "Closing output for card %s\n",
|
||
|
drvdata->card->shortname);
|
||
|
|
||
|
clear_bit(SERIAL_MODE_OUTPUT_OPEN, &drvdata->filemode);
|
||
|
clear_bit(SERIAL_MODE_OUTPUT_TRIGGERED, &drvdata->filemode);
|
||
|
|
||
|
if (!drvdata->filemode)
|
||
|
serdev_device_close(drvdata->serdev);
|
||
|
|
||
|
drvdata->midi_output = NULL;
|
||
|
|
||
|
return 0;
|
||
|
};
|
||
|
|
||
|
static void snd_serial_generic_output_trigger(struct snd_rawmidi_substream *substream,
|
||
|
int up)
|
||
|
{
|
||
|
struct snd_serial_generic *drvdata = substream->rmidi->card->private_data;
|
||
|
|
||
|
if (up)
|
||
|
set_bit(SERIAL_MODE_OUTPUT_TRIGGERED, &drvdata->filemode);
|
||
|
else
|
||
|
clear_bit(SERIAL_MODE_OUTPUT_TRIGGERED, &drvdata->filemode);
|
||
|
|
||
|
if (up)
|
||
|
snd_serial_generic_tx_wakeup(drvdata);
|
||
|
}
|
||
|
|
||
|
static void snd_serial_generic_output_drain(struct snd_rawmidi_substream *substream)
|
||
|
{
|
||
|
struct snd_serial_generic *drvdata = substream->rmidi->card->private_data;
|
||
|
|
||
|
/* Flush any pending characters */
|
||
|
serdev_device_write_flush(drvdata->serdev);
|
||
|
cancel_work_sync(&drvdata->tx_work);
|
||
|
}
|
||
|
|
||
|
static const struct snd_rawmidi_ops snd_serial_generic_output = {
|
||
|
.open = snd_serial_generic_output_open,
|
||
|
.close = snd_serial_generic_output_close,
|
||
|
.trigger = snd_serial_generic_output_trigger,
|
||
|
.drain = snd_serial_generic_output_drain,
|
||
|
};
|
||
|
|
||
|
static const struct snd_rawmidi_ops snd_serial_generic_input = {
|
||
|
.open = snd_serial_generic_input_open,
|
||
|
.close = snd_serial_generic_input_close,
|
||
|
.trigger = snd_serial_generic_input_trigger,
|
||
|
};
|
||
|
|
||
|
static void snd_serial_generic_parse_dt(struct serdev_device *serdev,
|
||
|
struct snd_serial_generic *drvdata)
|
||
|
{
|
||
|
int err;
|
||
|
|
||
|
err = of_property_read_u32(serdev->dev.of_node, "current-speed",
|
||
|
&drvdata->baudrate);
|
||
|
if (err < 0) {
|
||
|
dev_dbg(drvdata->card->dev,
|
||
|
"MIDI device reading of current-speed DT param failed with error %d, using default of 38400\n",
|
||
|
err);
|
||
|
drvdata->baudrate = 38400;
|
||
|
}
|
||
|
|
||
|
}
|
||
|
|
||
|
static void snd_serial_generic_substreams(struct snd_rawmidi_str *stream, int dev_num)
|
||
|
{
|
||
|
struct snd_rawmidi_substream *substream;
|
||
|
|
||
|
list_for_each_entry(substream, &stream->substreams, list) {
|
||
|
sprintf(substream->name, "Serial MIDI %d-%d", dev_num, substream->number);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
static int snd_serial_generic_rmidi(struct snd_serial_generic *drvdata,
|
||
|
int outs, int ins, struct snd_rawmidi **rmidi)
|
||
|
{
|
||
|
struct snd_rawmidi *rrawmidi;
|
||
|
int err;
|
||
|
|
||
|
err = snd_rawmidi_new(drvdata->card, drvdata->card->driver, 0,
|
||
|
outs, ins, &rrawmidi);
|
||
|
|
||
|
if (err < 0)
|
||
|
return err;
|
||
|
|
||
|
snd_rawmidi_set_ops(rrawmidi, SNDRV_RAWMIDI_STREAM_INPUT,
|
||
|
&snd_serial_generic_input);
|
||
|
snd_rawmidi_set_ops(rrawmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
|
||
|
&snd_serial_generic_output);
|
||
|
strcpy(rrawmidi->name, drvdata->card->shortname);
|
||
|
|
||
|
snd_serial_generic_substreams(&rrawmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT],
|
||
|
drvdata->serdev->ctrl->nr);
|
||
|
snd_serial_generic_substreams(&rrawmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT],
|
||
|
drvdata->serdev->ctrl->nr);
|
||
|
|
||
|
rrawmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
|
||
|
SNDRV_RAWMIDI_INFO_INPUT |
|
||
|
SNDRV_RAWMIDI_INFO_DUPLEX;
|
||
|
|
||
|
if (rmidi)
|
||
|
*rmidi = rrawmidi;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int snd_serial_generic_probe(struct serdev_device *serdev)
|
||
|
{
|
||
|
struct snd_card *card;
|
||
|
struct snd_serial_generic *drvdata;
|
||
|
int err;
|
||
|
|
||
|
err = snd_devm_card_new(&serdev->dev, SNDRV_DEFAULT_IDX1,
|
||
|
SNDRV_DEFAULT_STR1, THIS_MODULE,
|
||
|
sizeof(struct snd_serial_generic), &card);
|
||
|
|
||
|
if (err < 0)
|
||
|
return err;
|
||
|
|
||
|
strcpy(card->driver, "SerialMIDI");
|
||
|
sprintf(card->shortname, "SerialMIDI-%d", serdev->ctrl->nr);
|
||
|
sprintf(card->longname, "Serial MIDI device at serial%d", serdev->ctrl->nr);
|
||
|
|
||
|
drvdata = card->private_data;
|
||
|
|
||
|
drvdata->serdev = serdev;
|
||
|
drvdata->card = card;
|
||
|
|
||
|
snd_serial_generic_parse_dt(serdev, drvdata);
|
||
|
|
||
|
INIT_WORK(&drvdata->tx_work, snd_serial_generic_tx_work);
|
||
|
|
||
|
err = snd_serial_generic_rmidi(drvdata, 1, 1, &drvdata->rmidi);
|
||
|
if (err < 0)
|
||
|
return err;
|
||
|
|
||
|
serdev_device_set_client_ops(serdev, &snd_serial_generic_serdev_device_ops);
|
||
|
serdev_device_set_drvdata(drvdata->serdev, drvdata);
|
||
|
|
||
|
err = snd_card_register(card);
|
||
|
if (err < 0)
|
||
|
return err;
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static const struct of_device_id snd_serial_generic_dt_ids[] = {
|
||
|
{ .compatible = "serial-midi" },
|
||
|
{},
|
||
|
};
|
||
|
|
||
|
MODULE_DEVICE_TABLE(of, snd_serial_generic_dt_ids);
|
||
|
|
||
|
static struct serdev_device_driver snd_serial_generic_driver = {
|
||
|
.driver = {
|
||
|
.name = "snd-serial-generic",
|
||
|
.of_match_table = of_match_ptr(snd_serial_generic_dt_ids),
|
||
|
},
|
||
|
.probe = snd_serial_generic_probe,
|
||
|
};
|
||
|
|
||
|
module_serdev_device_driver(snd_serial_generic_driver);
|