// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Behringer BCD2000 driver
*
* Copyright (C) 2014 Mario Kicherer (dev@kicherer.org)
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/bitmap.h>
#include <linux/usb.h>
#include <linux/usb/audio.h>
#include <sound/core.h>
#include <sound/initval.h>
#include <sound/rawmidi.h>
#define PREFIX "snd-bcd2000: "
#define BUFSIZE 64
static const struct usb_device_id id_table[] = {
{ USB_DEVICE(0x1397, 0x00bd) },
{ },
};
static unsigned char device_cmd_prefix[] = {0x03, 0x00};
static unsigned char bcd2000_init_sequence[] = {
0x07, 0x00, 0x00, 0x00, 0x78, 0x48, 0x1c, 0x81,
0xc4, 0x00, 0x00, 0x00, 0x5e, 0x53, 0x4a, 0xf7,
0x18, 0xfa, 0x11, 0xff, 0x6c, 0xf3, 0x90, 0xff,
0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00,
0x18, 0xfa, 0x11, 0xff, 0x14, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0xf2, 0x34, 0x4a, 0xf7,
0x18, 0xfa, 0x11, 0xff
};
struct bcd2000 {
struct usb_device *dev;
struct snd_card *card;
struct usb_interface *intf;
int card_index;
int midi_out_active;
struct snd_rawmidi *rmidi;
struct snd_rawmidi_substream *midi_receive_substream;
struct snd_rawmidi_substream *midi_out_substream;
unsigned char midi_in_buf[BUFSIZE];
unsigned char midi_out_buf[BUFSIZE];
struct urb *midi_out_urb;
struct urb *midi_in_urb;
struct usb_anchor anchor;
};
static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;
static DEFINE_MUTEX(devices_mutex);
static DECLARE_BITMAP(devices_used, SNDRV_CARDS);
static struct usb_driver bcd2000_driver;
#ifdef [31mCONFIG_SND_DEBUG[0m
static void bcd2000_dump_buffer(const char *prefix, const char *buf, int len)
{
print_hex_dump(KERN_DEBUG, prefix,
DUMP_PREFIX_NONE, 16, 1,
buf, len, false);
}
#else
static void bcd2000_dump_buffer(const char *prefix, const char *buf, int len) {}
#endif
static int bcd2000_midi_input_open(struct snd_rawmidi_substream *substream)
{
return 0;
}
static int bcd2000_midi_input_close(struct snd_rawmidi_substream *substream)
{
return 0;
}
/* (de)register midi substream from client */
static void bcd2000_midi_input_trigger(struct snd_rawmidi_substream *substream,
int up)
{
struct bcd2000 *bcd2k = substream->rmidi->private_data;
bcd2k->midi_receive_substream = up ? substream : NULL;
}
static void bcd2000_midi_handle_input(struct bcd2000 *bcd2k,
const unsigned char *buf, unsigned int buf_len)
{
unsigned int payload_length, tocopy;
struct snd_rawmidi_substream *midi_receive_substream;
midi_receive_substream = READ_ONCE(bcd2k->midi_receive_substream);
if (!midi_receive_substream)
return;
bcd2000_dump_buffer(PREFIX "received from device: ", buf, buf_len);
if (buf_len < 2)
return;
payload_length = buf[0];
/* ignore packets without payload */
if (payload_length == 0)
return;
tocopy = min(payload_length, buf_len-1);
bcd2000_dump_buffer(PREFIX "sending to userspace: ",
&buf[1], tocopy);
snd_rawmidi_receive(midi_receive_substream,
&buf[1], tocopy);
}
static void bcd2000_midi_send(struct bcd2000 *bcd2k)
{
int len, ret;
struct snd_rawmidi_substream *midi_out_substream;
BUILD_BUG_ON(sizeof(device_cmd_prefix) >= BUFSIZE);
midi_out_substream = READ_ONCE(bcd2k->midi_out_substream);
if (!midi_out_substream)
return;
/* copy command prefix bytes */
memcpy(bcd2k->midi_out_buf, device_cmd_prefix,
sizeof(device_cmd_prefix));
/*
* get MIDI packet and leave space for command prefix
* and payload length
*/
len = snd_rawmidi_transmit(midi_out_substream,
bcd2k->midi_out_buf + 3, BUFSIZE - 3);
if (len < 0)
dev_err(&bcd2k->dev->dev, "%s: snd_rawmidi_transmit error %d\n",
__func__, len);
if (len <= 0)
return;
/* set payload length */
bcd2k->midi_out_buf[2] = len;
bcd2k->midi_out_urb->transfer_buffer_length = BUFSIZE;
bcd2000_dump_buffer(PREFIX "sending to device: ",
bcd2k->midi_out_buf, len+3);
/* send packet to the BCD2000 */
ret = usb_submit_urb(bcd2k->midi_out_urb, GFP_ATOMIC);
if (ret < 0)
dev_err(&bcd2k->dev->dev, PREFIX
"%s (%p): usb_submit_urb() failed, ret=%d, len=%d\n",
__func__, midi_out_substream, ret, len);
else
bcd2k->midi_out_active = 1;
}
static int bcd2000_midi_output_open(struct snd_rawmidi_substream *substream)
{
return 0;
}
static int bcd2000_midi_output_close(struct snd_rawmidi_substream *substream)
{
struct bcd2000 *bcd2k = substream->rmidi->private_data;
if (bcd2k->midi_out_active) {
usb_kill_urb(bcd2k->midi_out_urb);
bcd2k->midi_out_active = 0;
}
return 0;
}
/* (de)register midi substream from client */
static void bcd2000_midi_output_trigger(struct snd_rawmidi_substream *substream,
int up)
{
struct bcd2000 *bcd2k = substream->rmidi->private_data;
if (up) {
bcd2k->midi_out_substream = substream;
/* check if there is data userspace wants to send */
if (!bcd2k->midi_out_active)
bcd2000_midi_send(bcd2k);
} else {
bcd2k->midi_out_substream = NULL;
}
}
static void bcd2000_output_complete(struct urb *urb)
{
struct bcd2000 *bcd2k = urb->context;
bcd2k->midi_out_active = 0;
if (urb->status)
dev_warn(&urb->dev->dev,
PREFIX "output urb->status: %d\n", urb->status);
if (urb->status == -ESHUTDOWN)
return;
/* check if there is more data userspace wants to send */
bcd2000_midi_send(bcd2k);
}
static void bcd2000_input_complete(struct urb *urb)
{
int ret;
struct bcd2000 *bcd2k = urb->context;
if (urb->status)
dev_warn(&urb->dev->dev,
PREFIX "input urb->status: %i\n", urb->status);
if (!bcd2k || urb->status == -ESHUTDOWN)
return;
if (urb->actual_length > 0)
bcd2000_midi_handle_input(bcd2k, urb->transfer_buffer,
urb->actual_length);
/* return URB to device */
ret = usb_submit_urb(bcd2k->midi_in_urb, GFP_ATOMIC);
if (ret < 0)
dev_err(&bcd2k->dev->dev, PREFIX
"%s: usb_submit_urb() failed, ret=%d\n",
__func__, ret);
}
static const struct snd_rawmidi_ops bcd2000_midi_output = {
.open = bcd2000_midi_output_open,
.close = bcd2000_midi_output_close,
.trigger = bcd2000_midi_output_trigger,
};
static const struct snd_rawmidi_ops bcd2000_midi_input = {
.open = bcd2000_midi_input_open,
.close = bcd2000_midi_input_close,
.trigger = bcd2000_midi_input_trigger,
};
static void bcd2000_init_device(struct bcd2000 *bcd2k)
{
int ret;
init_usb_anchor(&bcd2k->anchor);
usb_anchor_urb(bcd2k->midi_out_urb, &bcd2k->anchor);
usb_anchor_urb(bcd2k->midi_in_urb, &bcd2k->anchor);
/* copy init sequence into buffer */
memcpy(bcd2k->midi_out_buf, bcd2000_init_sequence, 52);
bcd2k->midi_out_urb->transfer_buffer_length = 52;
/* submit sequence */
ret = usb_submit_urb(bcd2k->midi_out_urb, GFP_KERNEL);
if (ret < 0)
dev_err(&bcd2k->dev->dev, PREFIX
"%s: usb_submit_urb() out failed, ret=%d: ",
__func__, ret);
else
bcd2k->midi_out_active = 1;
/* pass URB to device to enable button and controller events */
ret = usb_submit_urb(bcd2k->midi_in_urb, GFP_KERNEL);
if (ret < 0)
dev_err(&bcd2k->dev->dev, PREFIX
"%s: usb_submit_urb() in failed, ret=%d: ",
__func__, ret);
/* ensure initialization is finished */
usb_wait_anchor_empty_timeout(&bcd2k->anchor, 1000);
}
static int bcd2000_init_midi(struct bcd2000 *bcd2k)
{
int ret;
struct snd_rawmidi *rmidi;
ret = snd_rawmidi_new(bcd2k->card, bcd2k->card->shortname, 0,
1, /* output */
1, /* input */
&rmidi);
if (ret < 0)
return ret;
strlcpy(rmidi->name, bcd2k->card->shortname, sizeof(rmidi->name));
rmidi->info_flags = SNDRV_RAWMIDI_INFO_DUPLEX;
rmidi->private_data = bcd2k;
rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT;
snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
&bcd2000_midi_output);
rmidi->info_flags |= SNDRV_RAWMIDI_INFO_INPUT;
snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT,
&bcd2000_midi_input);
bcd2k->rmidi = rmidi;
bcd2k->midi_in_urb = usb_alloc_urb(0, GFP_KERNEL);
bcd2k->midi_out_urb = usb_alloc_urb(0, GFP_KERNEL);
if (!bcd2k->midi_in_urb || !bcd2k->midi_out_urb) {
dev_err(&bcd2k->dev->dev, PREFIX "usb_alloc_urb failed\n");
return -ENOMEM;
}
usb_fill_int_urb(bcd2k->midi_in_urb, bcd2k->dev,
usb_rcvintpipe(bcd2k->dev, 0x81),
bcd2k->midi_in_buf, BUFSIZE,
bcd2000_input_complete, bcd2k, 1);
usb_fill_int_urb(bcd2k->midi_out_urb, bcd2k->dev,
usb_sndintpipe(bcd2k->dev, 0x1),
bcd2k->midi_out_buf, BUFSIZE,
bcd2000_output_complete, bcd2k, 1);
/* sanity checks of EPs before actually submitting */
if (usb_urb_ep_type_check(bcd2k->midi_in_urb) ||
usb_urb_ep_type_check(bcd2k->midi_out_urb)) {
dev_err(&bcd2k->dev->dev, "invalid MIDI EP\n");
return -EINVAL;
}
bcd2000_init_device(bcd2k);
return 0;
}
static void bcd2000_free_usb_related_resources(struct bcd2000 *bcd2k,
struct usb_interface *interface)
{
/* usb_kill_urb not necessary, urb is aborted automatically */
usb_free_urb(bcd2k->midi_out_urb);
usb_free_urb(bcd2k->midi_in_urb);
if (bcd2k->intf) {
usb_set_intfdata(bcd2k->intf, NULL);
bcd2k->intf = NULL;
}
}
static int bcd2000_probe(struct usb_interface *interface,
const struct usb_device_id *usb_id)
{
struct snd_card *card;
struct bcd2000 *bcd2k;
unsigned int card_index;
char usb_path[32];
int err;
mutex_lock(&devices_mutex);
for (card_index = 0; card_index < SNDRV_CARDS; ++card_index)
if (!test_bit(card_index, devices_used))
break;
if (card_index >= SNDRV_CARDS) {
mutex_unlock(&devices_mutex);
return -ENOENT;
}
err = snd_card_new(&interface->dev, index[card_index], id[card_index],
THIS_MODULE, sizeof(*bcd2k), &card);
if (err < 0) {
mutex_unlock(&devices_mutex);
return err;
}
bcd2k = card->private_data;
bcd2k->dev = interface_to_usbdev(interface);
bcd2k->card = card;
bcd2k->card_index = card_index;
bcd2k->intf = interface;
snd_card_set_dev(card, &interface->dev);
strncpy(card->driver, "snd-bcd2000", sizeof(card->driver));
strncpy(card->shortname, "BCD2000", sizeof(card->shortname));
usb_make_path(bcd2k->dev, usb_path, sizeof(usb_path));
snprintf(bcd2k->card->longname, sizeof(bcd2k->card->longname),
"Behringer BCD2000 at %s",
usb_path);
err = bcd2000_init_midi(bcd2k);
if (err < 0)
goto probe_error;
err = snd_card_register(card);
if (err < 0)
goto probe_error;
usb_set_intfdata(interface, bcd2k);
set_bit(card_index, devices_used);
mutex_unlock(&devices_mutex);
return 0;
probe_error:
dev_info(&bcd2k->dev->dev, PREFIX "error during probing");
bcd2000_free_usb_related_resources(bcd2k, interface);
snd_card_free(card);
mutex_unlock(&devices_mutex);
return err;
}
static void bcd2000_disconnect(struct usb_interface *interface)
{
struct bcd2000 *bcd2k = usb_get_intfdata(interface);
if (!bcd2k)
return;
mutex_lock(&devices_mutex);
/* make sure that userspace cannot create new requests */
snd_card_disconnect(bcd2k->card);
bcd2000_free_usb_related_resources(bcd2k, interface);
clear_bit(bcd2k->card_index, devices_used);
snd_card_free_when_closed(bcd2k->card);
mutex_unlock(&devices_mutex);
}
static struct usb_driver bcd2000_driver = {
.name = "snd-bcd2000",
.probe = bcd2000_probe,
.disconnect = bcd2000_disconnect,
.id_table = id_table,
};
module_usb_driver(bcd2000_driver);
MODULE_DEVICE_TABLE(usb, id_table);
MODULE_AUTHOR("Mario Kicherer, dev@kicherer.org");
MODULE_DESCRIPTION("Behringer BCD2000 driver");
MODULE_LICENSE("GPL");