1 files changed, 460 insertions, 0 deletions

diff --git a/sound/usb/bcd2000/bcd2000.c b/sound/usb/bcd2000/bcd2000.c
new file mode 100644
index 000000000..01f0b3297
--- /dev/null
+++ b/sound/usb/bcd2000/bcd2000.c
@@ -0,0 +1,460 @@
+// 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 const unsigned char device_cmd_prefix[] = {0x03, 0x00};
+
+static const 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 CONFIG_SND_DEBUG
+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(bcd2k->midi_out_urb);
+	usb_kill_urb(bcd2k->midi_in_urb);
+
+	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");