ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/drivers/usb/gadget/function/f_midi.c b/marvell/linux/drivers/usb/gadget/function/f_midi.c
new file mode 100644
index 0000000..6745919
--- /dev/null
+++ b/marvell/linux/drivers/usb/gadget/function/f_midi.c
@@ -0,0 +1,1428 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * f_midi.c -- USB MIDI class function driver
+ *
+ * Copyright (C) 2006 Thumtronics Pty Ltd.
+ * Developed for Thumtronics by Grey Innovation
+ * Ben Williamson <ben.williamson@greyinnovation.com>
+ *
+ * Rewritten for the composite framework
+ * Copyright (C) 2011 Daniel Mack <zonque@gmail.com>
+ *
+ * Based on drivers/usb/gadget/f_audio.c,
+ * Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
+ * Copyright (C) 2008 Analog Devices, Inc
+ *
+ * and drivers/usb/gadget/midi.c,
+ * Copyright (C) 2006 Thumtronics Pty Ltd.
+ * Ben Williamson <ben.williamson@greyinnovation.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+#include <linux/kfifo.h>
+#include <linux/spinlock.h>
+
+#include <sound/core.h>
+#include <sound/initval.h>
+#include <sound/rawmidi.h>
+
+#include <linux/usb/ch9.h>
+#include <linux/usb/gadget.h>
+#include <linux/usb/audio.h>
+#include <linux/usb/midi.h>
+
+#include "u_f.h"
+#include "u_midi.h"
+
+MODULE_AUTHOR("Ben Williamson");
+MODULE_LICENSE("GPL v2");
+
+static const char f_midi_shortname[] = "f_midi";
+static const char f_midi_longname[] = "MIDI Gadget";
+
+/*
+ * We can only handle 16 cables on one single endpoint, as cable numbers are
+ * stored in 4-bit fields. And as the interface currently only holds one
+ * single endpoint, this is the maximum number of ports we can allow.
+ */
+#define MAX_PORTS 16
+
+/* MIDI message states */
+enum {
+ STATE_INITIAL = 0, /* pseudo state */
+ STATE_1PARAM,
+ STATE_2PARAM_1,
+ STATE_2PARAM_2,
+ STATE_SYSEX_0,
+ STATE_SYSEX_1,
+ STATE_SYSEX_2,
+ STATE_REAL_TIME,
+ STATE_FINISHED, /* pseudo state */
+};
+
+/*
+ * This is a gadget, and the IN/OUT naming is from the host's perspective.
+ * USB -> OUT endpoint -> rawmidi
+ * USB <- IN endpoint <- rawmidi
+ */
+struct gmidi_in_port {
+ struct snd_rawmidi_substream *substream;
+ int active;
+ uint8_t cable;
+ uint8_t state;
+ uint8_t data[2];
+};
+
+struct f_midi {
+ struct usb_function func;
+ struct usb_gadget *gadget;
+ struct usb_ep *in_ep, *out_ep;
+ struct snd_card *card;
+ struct snd_rawmidi *rmidi;
+ u8 ms_id;
+
+ struct snd_rawmidi_substream *out_substream[MAX_PORTS];
+
+ unsigned long out_triggered;
+ struct tasklet_struct tasklet;
+ unsigned int in_ports;
+ unsigned int out_ports;
+ int index;
+ char *id;
+ unsigned int buflen, qlen;
+ /* This fifo is used as a buffer ring for pre-allocated IN usb_requests */
+ DECLARE_KFIFO_PTR(in_req_fifo, struct usb_request *);
+ spinlock_t transmit_lock;
+ unsigned int in_last_port;
+ unsigned char free_ref;
+
+ struct gmidi_in_port in_ports_array[/* in_ports */];
+};
+
+static inline struct f_midi *func_to_midi(struct usb_function *f)
+{
+ return container_of(f, struct f_midi, func);
+}
+
+static void f_midi_transmit(struct f_midi *midi);
+static void f_midi_rmidi_free(struct snd_rawmidi *rmidi);
+static void f_midi_free_inst(struct usb_function_instance *f);
+
+DECLARE_UAC_AC_HEADER_DESCRIPTOR(1);
+DECLARE_USB_MIDI_OUT_JACK_DESCRIPTOR(1);
+DECLARE_USB_MS_ENDPOINT_DESCRIPTOR(16);
+
+/* B.3.1 Standard AC Interface Descriptor */
+static struct usb_interface_descriptor ac_interface_desc = {
+ .bLength = USB_DT_INTERFACE_SIZE,
+ .bDescriptorType = USB_DT_INTERFACE,
+ /* .bInterfaceNumber = DYNAMIC */
+ /* .bNumEndpoints = DYNAMIC */
+ .bInterfaceClass = USB_CLASS_AUDIO,
+ .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL,
+ /* .iInterface = DYNAMIC */
+};
+
+/* B.3.2 Class-Specific AC Interface Descriptor */
+static struct uac1_ac_header_descriptor_1 ac_header_desc = {
+ .bLength = UAC_DT_AC_HEADER_SIZE(1),
+ .bDescriptorType = USB_DT_CS_INTERFACE,
+ .bDescriptorSubtype = USB_MS_HEADER,
+ .bcdADC = cpu_to_le16(0x0100),
+ .wTotalLength = cpu_to_le16(UAC_DT_AC_HEADER_SIZE(1)),
+ .bInCollection = 1,
+ /* .baInterfaceNr = DYNAMIC */
+};
+
+/* B.4.1 Standard MS Interface Descriptor */
+static struct usb_interface_descriptor ms_interface_desc = {
+ .bLength = USB_DT_INTERFACE_SIZE,
+ .bDescriptorType = USB_DT_INTERFACE,
+ /* .bInterfaceNumber = DYNAMIC */
+ .bNumEndpoints = 2,
+ .bInterfaceClass = USB_CLASS_AUDIO,
+ .bInterfaceSubClass = USB_SUBCLASS_MIDISTREAMING,
+ /* .iInterface = DYNAMIC */
+};
+
+/* B.4.2 Class-Specific MS Interface Descriptor */
+static struct usb_ms_header_descriptor ms_header_desc = {
+ .bLength = USB_DT_MS_HEADER_SIZE,
+ .bDescriptorType = USB_DT_CS_INTERFACE,
+ .bDescriptorSubtype = USB_MS_HEADER,
+ .bcdMSC = cpu_to_le16(0x0100),
+ /* .wTotalLength = DYNAMIC */
+};
+
+/* B.5.1 Standard Bulk OUT Endpoint Descriptor */
+static struct usb_endpoint_descriptor bulk_out_desc = {
+ .bLength = USB_DT_ENDPOINT_AUDIO_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = USB_DIR_OUT,
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+};
+
+static struct usb_ss_ep_comp_descriptor bulk_out_ss_comp_desc = {
+ .bLength = sizeof(bulk_out_ss_comp_desc),
+ .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
+ /* .bMaxBurst = 0, */
+ /* .bmAttributes = 0, */
+};
+
+/* B.5.2 Class-specific MS Bulk OUT Endpoint Descriptor */
+static struct usb_ms_endpoint_descriptor_16 ms_out_desc = {
+ /* .bLength = DYNAMIC */
+ .bDescriptorType = USB_DT_CS_ENDPOINT,
+ .bDescriptorSubtype = USB_MS_GENERAL,
+ /* .bNumEmbMIDIJack = DYNAMIC */
+ /* .baAssocJackID = DYNAMIC */
+};
+
+/* B.6.1 Standard Bulk IN Endpoint Descriptor */
+static struct usb_endpoint_descriptor bulk_in_desc = {
+ .bLength = USB_DT_ENDPOINT_AUDIO_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bEndpointAddress = USB_DIR_IN,
+ .bmAttributes = USB_ENDPOINT_XFER_BULK,
+};
+
+static struct usb_ss_ep_comp_descriptor bulk_in_ss_comp_desc = {
+ .bLength = sizeof(bulk_in_ss_comp_desc),
+ .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
+ /* .bMaxBurst = 0, */
+ /* .bmAttributes = 0, */
+};
+
+/* B.6.2 Class-specific MS Bulk IN Endpoint Descriptor */
+static struct usb_ms_endpoint_descriptor_16 ms_in_desc = {
+ /* .bLength = DYNAMIC */
+ .bDescriptorType = USB_DT_CS_ENDPOINT,
+ .bDescriptorSubtype = USB_MS_GENERAL,
+ /* .bNumEmbMIDIJack = DYNAMIC */
+ /* .baAssocJackID = DYNAMIC */
+};
+
+/* string IDs are assigned dynamically */
+
+#define STRING_FUNC_IDX 0
+
+static struct usb_string midi_string_defs[] = {
+ [STRING_FUNC_IDX].s = "MIDI function",
+ { } /* end of list */
+};
+
+static struct usb_gadget_strings midi_stringtab = {
+ .language = 0x0409, /* en-us */
+ .strings = midi_string_defs,
+};
+
+static struct usb_gadget_strings *midi_strings[] = {
+ &midi_stringtab,
+ NULL,
+};
+
+static inline struct usb_request *midi_alloc_ep_req(struct usb_ep *ep,
+ unsigned length)
+{
+ return alloc_ep_req(ep, length);
+}
+
+static const uint8_t f_midi_cin_length[] = {
+ 0, 0, 2, 3, 3, 1, 2, 3, 3, 3, 3, 3, 2, 2, 3, 1
+};
+
+/*
+ * Receives a chunk of MIDI data.
+ */
+static void f_midi_read_data(struct usb_ep *ep, int cable,
+ uint8_t *data, int length)
+{
+ struct f_midi *midi = ep->driver_data;
+ struct snd_rawmidi_substream *substream = midi->out_substream[cable];
+
+ if (!substream)
+ /* Nobody is listening - throw it on the floor. */
+ return;
+
+ if (!test_bit(cable, &midi->out_triggered))
+ return;
+
+ snd_rawmidi_receive(substream, data, length);
+}
+
+static void f_midi_handle_out_data(struct usb_ep *ep, struct usb_request *req)
+{
+ unsigned int i;
+ u8 *buf = req->buf;
+
+ for (i = 0; i + 3 < req->actual; i += 4)
+ if (buf[i] != 0) {
+ int cable = buf[i] >> 4;
+ int length = f_midi_cin_length[buf[i] & 0x0f];
+ f_midi_read_data(ep, cable, &buf[i + 1], length);
+ }
+}
+
+static void
+f_midi_complete(struct usb_ep *ep, struct usb_request *req)
+{
+ struct f_midi *midi = ep->driver_data;
+ struct usb_composite_dev *cdev = midi->func.config->cdev;
+ int status = req->status;
+
+ switch (status) {
+ case 0: /* normal completion */
+ if (ep == midi->out_ep) {
+ /* We received stuff. req is queued again, below */
+ f_midi_handle_out_data(ep, req);
+ } else if (ep == midi->in_ep) {
+ /* Our transmit completed. See if there's more to go.
+ * f_midi_transmit eats req, don't queue it again. */
+ req->length = 0;
+ f_midi_transmit(midi);
+ return;
+ }
+ break;
+
+ /* this endpoint is normally active while we're configured */
+ case -ECONNABORTED: /* hardware forced ep reset */
+ case -ECONNRESET: /* request dequeued */
+ case -ESHUTDOWN: /* disconnect from host */
+ VDBG(cdev, "%s gone (%d), %d/%d\n", ep->name, status,
+ req->actual, req->length);
+ if (ep == midi->out_ep) {
+ f_midi_handle_out_data(ep, req);
+ /* We don't need to free IN requests because it's handled
+ * by the midi->in_req_fifo. */
+ free_ep_req(ep, req);
+ }
+ return;
+
+ case -EOVERFLOW: /* buffer overrun on read means that
+ * we didn't provide a big enough buffer.
+ */
+ default:
+ DBG(cdev, "%s complete --> %d, %d/%d\n", ep->name,
+ status, req->actual, req->length);
+ break;
+ case -EREMOTEIO: /* short read */
+ break;
+ }
+
+ status = usb_ep_queue(ep, req, GFP_ATOMIC);
+ if (status) {
+ ERROR(cdev, "kill %s: resubmit %d bytes --> %d\n",
+ ep->name, req->length, status);
+ usb_ep_set_halt(ep);
+ /* FIXME recover later ... somehow */
+ }
+}
+
+static void f_midi_drop_out_substreams(struct f_midi *midi)
+{
+ unsigned int i;
+
+ for (i = 0; i < midi->in_ports; i++) {
+ struct gmidi_in_port *port = midi->in_ports_array + i;
+ struct snd_rawmidi_substream *substream = port->substream;
+
+ if (port->active && substream)
+ snd_rawmidi_drop_output(substream);
+ }
+}
+
+static int f_midi_start_ep(struct f_midi *midi,
+ struct usb_function *f,
+ struct usb_ep *ep)
+{
+ int err;
+ struct usb_composite_dev *cdev = f->config->cdev;
+
+ usb_ep_disable(ep);
+
+ err = config_ep_by_speed(midi->gadget, f, ep);
+ if (err) {
+ ERROR(cdev, "can't configure %s: %d\n", ep->name, err);
+ return err;
+ }
+
+ err = usb_ep_enable(ep);
+ if (err) {
+ ERROR(cdev, "can't start %s: %d\n", ep->name, err);
+ return err;
+ }
+
+ ep->driver_data = midi;
+
+ return 0;
+}
+
+static int f_midi_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
+{
+ struct f_midi *midi = func_to_midi(f);
+ unsigned i;
+ int err;
+
+ /* we only set alt for MIDIStreaming interface */
+ if (intf != midi->ms_id)
+ return 0;
+
+ err = f_midi_start_ep(midi, f, midi->in_ep);
+ if (err)
+ return err;
+
+ err = f_midi_start_ep(midi, f, midi->out_ep);
+ if (err)
+ return err;
+
+ /* pre-allocate write usb requests to use on f_midi_transmit. */
+ while (kfifo_avail(&midi->in_req_fifo)) {
+ struct usb_request *req =
+ midi_alloc_ep_req(midi->in_ep, midi->buflen);
+
+ if (req == NULL)
+ return -ENOMEM;
+
+ req->length = 0;
+ req->complete = f_midi_complete;
+
+ kfifo_put(&midi->in_req_fifo, req);
+ }
+
+ /* allocate a bunch of read buffers and queue them all at once. */
+ for (i = 0; i < midi->qlen && err == 0; i++) {
+ struct usb_request *req =
+ midi_alloc_ep_req(midi->out_ep, midi->buflen);
+
+ if (req == NULL)
+ return -ENOMEM;
+
+ req->complete = f_midi_complete;
+ err = usb_ep_queue(midi->out_ep, req, GFP_ATOMIC);
+ if (err) {
+ ERROR(midi, "%s: couldn't enqueue request: %d\n",
+ midi->out_ep->name, err);
+ if (req->buf != NULL)
+ free_ep_req(midi->out_ep, req);
+ return err;
+ }
+ }
+
+ return 0;
+}
+
+static void f_midi_disable(struct usb_function *f)
+{
+ struct f_midi *midi = func_to_midi(f);
+ struct usb_composite_dev *cdev = f->config->cdev;
+ struct usb_request *req = NULL;
+
+ DBG(cdev, "disable\n");
+
+ /*
+ * just disable endpoints, forcing completion of pending i/o.
+ * all our completion handlers free their requests in this case.
+ */
+ usb_ep_disable(midi->in_ep);
+ usb_ep_disable(midi->out_ep);
+
+ /* release IN requests */
+ while (kfifo_get(&midi->in_req_fifo, &req))
+ free_ep_req(midi->in_ep, req);
+
+ f_midi_drop_out_substreams(midi);
+}
+
+static int f_midi_snd_free(struct snd_device *device)
+{
+ return 0;
+}
+
+/*
+ * Converts MIDI commands to USB MIDI packets.
+ */
+static void f_midi_transmit_byte(struct usb_request *req,
+ struct gmidi_in_port *port, uint8_t b)
+{
+ uint8_t p[4] = { port->cable << 4, 0, 0, 0 };
+ uint8_t next_state = STATE_INITIAL;
+
+ switch (b) {
+ case 0xf8 ... 0xff:
+ /* System Real-Time Messages */
+ p[0] |= 0x0f;
+ p[1] = b;
+ next_state = port->state;
+ port->state = STATE_REAL_TIME;
+ break;
+
+ case 0xf7:
+ /* End of SysEx */
+ switch (port->state) {
+ case STATE_SYSEX_0:
+ p[0] |= 0x05;
+ p[1] = 0xf7;
+ next_state = STATE_FINISHED;
+ break;
+ case STATE_SYSEX_1:
+ p[0] |= 0x06;
+ p[1] = port->data[0];
+ p[2] = 0xf7;
+ next_state = STATE_FINISHED;
+ break;
+ case STATE_SYSEX_2:
+ p[0] |= 0x07;
+ p[1] = port->data[0];
+ p[2] = port->data[1];
+ p[3] = 0xf7;
+ next_state = STATE_FINISHED;
+ break;
+ default:
+ /* Ignore byte */
+ next_state = port->state;
+ port->state = STATE_INITIAL;
+ }
+ break;
+
+ case 0xf0 ... 0xf6:
+ /* System Common Messages */
+ port->data[0] = port->data[1] = 0;
+ port->state = STATE_INITIAL;
+ switch (b) {
+ case 0xf0:
+ port->data[0] = b;
+ port->data[1] = 0;
+ next_state = STATE_SYSEX_1;
+ break;
+ case 0xf1:
+ case 0xf3:
+ port->data[0] = b;
+ next_state = STATE_1PARAM;
+ break;
+ case 0xf2:
+ port->data[0] = b;
+ next_state = STATE_2PARAM_1;
+ break;
+ case 0xf4:
+ case 0xf5:
+ next_state = STATE_INITIAL;
+ break;
+ case 0xf6:
+ p[0] |= 0x05;
+ p[1] = 0xf6;
+ next_state = STATE_FINISHED;
+ break;
+ }
+ break;
+
+ case 0x80 ... 0xef:
+ /*
+ * Channel Voice Messages, Channel Mode Messages
+ * and Control Change Messages.
+ */
+ port->data[0] = b;
+ port->data[1] = 0;
+ port->state = STATE_INITIAL;
+ if (b >= 0xc0 && b <= 0xdf)
+ next_state = STATE_1PARAM;
+ else
+ next_state = STATE_2PARAM_1;
+ break;
+
+ case 0x00 ... 0x7f:
+ /* Message parameters */
+ switch (port->state) {
+ case STATE_1PARAM:
+ if (port->data[0] < 0xf0)
+ p[0] |= port->data[0] >> 4;
+ else
+ p[0] |= 0x02;
+
+ p[1] = port->data[0];
+ p[2] = b;
+ /* This is to allow Running State Messages */
+ next_state = STATE_1PARAM;
+ break;
+ case STATE_2PARAM_1:
+ port->data[1] = b;
+ next_state = STATE_2PARAM_2;
+ break;
+ case STATE_2PARAM_2:
+ if (port->data[0] < 0xf0)
+ p[0] |= port->data[0] >> 4;
+ else
+ p[0] |= 0x03;
+
+ p[1] = port->data[0];
+ p[2] = port->data[1];
+ p[3] = b;
+ /* This is to allow Running State Messages */
+ next_state = STATE_2PARAM_1;
+ break;
+ case STATE_SYSEX_0:
+ port->data[0] = b;
+ next_state = STATE_SYSEX_1;
+ break;
+ case STATE_SYSEX_1:
+ port->data[1] = b;
+ next_state = STATE_SYSEX_2;
+ break;
+ case STATE_SYSEX_2:
+ p[0] |= 0x04;
+ p[1] = port->data[0];
+ p[2] = port->data[1];
+ p[3] = b;
+ next_state = STATE_SYSEX_0;
+ break;
+ }
+ break;
+ }
+
+ /* States where we have to write into the USB request */
+ if (next_state == STATE_FINISHED ||
+ port->state == STATE_SYSEX_2 ||
+ port->state == STATE_1PARAM ||
+ port->state == STATE_2PARAM_2 ||
+ port->state == STATE_REAL_TIME) {
+
+ unsigned int length = req->length;
+ u8 *buf = (u8 *)req->buf + length;
+
+ memcpy(buf, p, sizeof(p));
+ req->length = length + sizeof(p);
+
+ if (next_state == STATE_FINISHED) {
+ next_state = STATE_INITIAL;
+ port->data[0] = port->data[1] = 0;
+ }
+ }
+
+ port->state = next_state;
+}
+
+static int f_midi_do_transmit(struct f_midi *midi, struct usb_ep *ep)
+{
+ struct usb_request *req = NULL;
+ unsigned int len, i;
+ bool active = false;
+ int err;
+
+ /*
+ * We peek the request in order to reuse it if it fails to enqueue on
+ * its endpoint
+ */
+ len = kfifo_peek(&midi->in_req_fifo, &req);
+ if (len != 1) {
+ ERROR(midi, "%s: Couldn't get usb request\n", __func__);
+ return -1;
+ }
+
+ /*
+ * If buffer overrun, then we ignore this transmission.
+ * IMPORTANT: This will cause the user-space rawmidi device to block
+ * until a) usb requests have been completed or b) snd_rawmidi_write()
+ * times out.
+ */
+ if (req->length > 0)
+ return 0;
+
+ for (i = midi->in_last_port; i < midi->in_ports; ++i) {
+ struct gmidi_in_port *port = midi->in_ports_array + i;
+ struct snd_rawmidi_substream *substream = port->substream;
+
+ if (!port->active || !substream)
+ continue;
+
+ while (req->length + 3 < midi->buflen) {
+ uint8_t b;
+
+ if (snd_rawmidi_transmit(substream, &b, 1) != 1) {
+ port->active = 0;
+ break;
+ }
+ f_midi_transmit_byte(req, port, b);
+ }
+
+ active = !!port->active;
+ if (active)
+ break;
+ }
+ midi->in_last_port = active ? i : 0;
+
+ if (req->length <= 0)
+ goto done;
+
+ err = usb_ep_queue(ep, req, GFP_ATOMIC);
+ if (err < 0) {
+ ERROR(midi, "%s failed to queue req: %d\n",
+ midi->in_ep->name, err);
+ req->length = 0; /* Re-use request next time. */
+ } else {
+ /* Upon success, put request at the back of the queue. */
+ kfifo_skip(&midi->in_req_fifo);
+ kfifo_put(&midi->in_req_fifo, req);
+ }
+
+done:
+ return active;
+}
+
+static void f_midi_transmit(struct f_midi *midi)
+{
+ struct usb_ep *ep = midi->in_ep;
+ int ret;
+ unsigned long flags;
+
+ /* We only care about USB requests if IN endpoint is enabled */
+ if (!ep || !ep->enabled)
+ goto drop_out;
+
+ spin_lock_irqsave(&midi->transmit_lock, flags);
+
+ do {
+ ret = f_midi_do_transmit(midi, ep);
+ if (ret < 0) {
+ spin_unlock_irqrestore(&midi->transmit_lock, flags);
+ goto drop_out;
+ }
+ } while (ret);
+
+ spin_unlock_irqrestore(&midi->transmit_lock, flags);
+
+ return;
+
+drop_out:
+ f_midi_drop_out_substreams(midi);
+}
+
+static void f_midi_in_tasklet(unsigned long data)
+{
+ struct f_midi *midi = (struct f_midi *) data;
+ f_midi_transmit(midi);
+}
+
+static int f_midi_in_open(struct snd_rawmidi_substream *substream)
+{
+ struct f_midi *midi = substream->rmidi->private_data;
+ struct gmidi_in_port *port;
+
+ if (substream->number >= midi->in_ports)
+ return -EINVAL;
+
+ VDBG(midi, "%s()\n", __func__);
+ port = midi->in_ports_array + substream->number;
+ port->substream = substream;
+ port->state = STATE_INITIAL;
+ return 0;
+}
+
+static int f_midi_in_close(struct snd_rawmidi_substream *substream)
+{
+ struct f_midi *midi = substream->rmidi->private_data;
+
+ VDBG(midi, "%s()\n", __func__);
+ return 0;
+}
+
+static void f_midi_in_trigger(struct snd_rawmidi_substream *substream, int up)
+{
+ struct f_midi *midi = substream->rmidi->private_data;
+
+ if (substream->number >= midi->in_ports)
+ return;
+
+ VDBG(midi, "%s() %d\n", __func__, up);
+ midi->in_ports_array[substream->number].active = up;
+ if (up)
+ tasklet_hi_schedule(&midi->tasklet);
+}
+
+static int f_midi_out_open(struct snd_rawmidi_substream *substream)
+{
+ struct f_midi *midi = substream->rmidi->private_data;
+
+ if (substream->number >= MAX_PORTS)
+ return -EINVAL;
+
+ VDBG(midi, "%s()\n", __func__);
+ midi->out_substream[substream->number] = substream;
+ return 0;
+}
+
+static int f_midi_out_close(struct snd_rawmidi_substream *substream)
+{
+ struct f_midi *midi = substream->rmidi->private_data;
+
+ VDBG(midi, "%s()\n", __func__);
+ return 0;
+}
+
+static void f_midi_out_trigger(struct snd_rawmidi_substream *substream, int up)
+{
+ struct f_midi *midi = substream->rmidi->private_data;
+
+ VDBG(midi, "%s()\n", __func__);
+
+ if (up)
+ set_bit(substream->number, &midi->out_triggered);
+ else
+ clear_bit(substream->number, &midi->out_triggered);
+}
+
+static const struct snd_rawmidi_ops gmidi_in_ops = {
+ .open = f_midi_in_open,
+ .close = f_midi_in_close,
+ .trigger = f_midi_in_trigger,
+};
+
+static const struct snd_rawmidi_ops gmidi_out_ops = {
+ .open = f_midi_out_open,
+ .close = f_midi_out_close,
+ .trigger = f_midi_out_trigger
+};
+
+static inline void f_midi_unregister_card(struct f_midi *midi)
+{
+ if (midi->card) {
+ snd_card_free(midi->card);
+ midi->card = NULL;
+ }
+}
+
+/* register as a sound "card" */
+static int f_midi_register_card(struct f_midi *midi)
+{
+ struct snd_card *card;
+ struct snd_rawmidi *rmidi;
+ int err;
+ static struct snd_device_ops ops = {
+ .dev_free = f_midi_snd_free,
+ };
+
+ err = snd_card_new(&midi->gadget->dev, midi->index, midi->id,
+ THIS_MODULE, 0, &card);
+ if (err < 0) {
+ ERROR(midi, "snd_card_new() failed\n");
+ goto fail;
+ }
+ midi->card = card;
+
+ err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, midi, &ops);
+ if (err < 0) {
+ ERROR(midi, "snd_device_new() failed: error %d\n", err);
+ goto fail;
+ }
+
+ strcpy(card->driver, f_midi_longname);
+ strcpy(card->longname, f_midi_longname);
+ strcpy(card->shortname, f_midi_shortname);
+
+ /* Set up rawmidi */
+ snd_component_add(card, "MIDI");
+ err = snd_rawmidi_new(card, card->longname, 0,
+ midi->out_ports, midi->in_ports, &rmidi);
+ if (err < 0) {
+ ERROR(midi, "snd_rawmidi_new() failed: error %d\n", err);
+ goto fail;
+ }
+ midi->rmidi = rmidi;
+ midi->in_last_port = 0;
+ strcpy(rmidi->name, card->shortname);
+ rmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
+ SNDRV_RAWMIDI_INFO_INPUT |
+ SNDRV_RAWMIDI_INFO_DUPLEX;
+ rmidi->private_data = midi;
+ rmidi->private_free = f_midi_rmidi_free;
+ midi->free_ref++;
+
+ /*
+ * Yes, rawmidi OUTPUT = USB IN, and rawmidi INPUT = USB OUT.
+ * It's an upside-down world being a gadget.
+ */
+ snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &gmidi_in_ops);
+ snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &gmidi_out_ops);
+
+ /* register it - we're ready to go */
+ err = snd_card_register(card);
+ if (err < 0) {
+ ERROR(midi, "snd_card_register() failed\n");
+ goto fail;
+ }
+
+ VDBG(midi, "%s() finished ok\n", __func__);
+ return 0;
+
+fail:
+ f_midi_unregister_card(midi);
+ return err;
+}
+
+/* MIDI function driver setup/binding */
+
+static int f_midi_bind(struct usb_configuration *c, struct usb_function *f)
+{
+ struct usb_descriptor_header **midi_function;
+ struct usb_midi_in_jack_descriptor jack_in_ext_desc[MAX_PORTS];
+ struct usb_midi_in_jack_descriptor jack_in_emb_desc[MAX_PORTS];
+ struct usb_midi_out_jack_descriptor_1 jack_out_ext_desc[MAX_PORTS];
+ struct usb_midi_out_jack_descriptor_1 jack_out_emb_desc[MAX_PORTS];
+ struct usb_composite_dev *cdev = c->cdev;
+ struct f_midi *midi = func_to_midi(f);
+ struct usb_string *us;
+ int status, n, jack = 1, i = 0, endpoint_descriptor_index = 0;
+
+ midi->gadget = cdev->gadget;
+ tasklet_init(&midi->tasklet, f_midi_in_tasklet, (unsigned long) midi);
+ status = f_midi_register_card(midi);
+ if (status < 0)
+ goto fail_register;
+
+ /* maybe allocate device-global string ID */
+ us = usb_gstrings_attach(c->cdev, midi_strings,
+ ARRAY_SIZE(midi_string_defs));
+ if (IS_ERR(us)) {
+ status = PTR_ERR(us);
+ goto fail;
+ }
+ ac_interface_desc.iInterface = us[STRING_FUNC_IDX].id;
+
+ /* We have two interfaces, AudioControl and MIDIStreaming */
+ status = usb_interface_id(c, f);
+ if (status < 0)
+ goto fail;
+ ac_interface_desc.bInterfaceNumber = status;
+
+ status = usb_interface_id(c, f);
+ if (status < 0)
+ goto fail;
+ ms_interface_desc.bInterfaceNumber = status;
+ ac_header_desc.baInterfaceNr[0] = status;
+ midi->ms_id = status;
+
+ status = -ENODEV;
+
+ /* allocate instance-specific endpoints */
+ midi->in_ep = usb_ep_autoconfig(cdev->gadget, &bulk_in_desc);
+ if (!midi->in_ep)
+ goto fail;
+
+ midi->out_ep = usb_ep_autoconfig(cdev->gadget, &bulk_out_desc);
+ if (!midi->out_ep)
+ goto fail;
+
+ /* allocate temporary function list */
+ midi_function = kcalloc((MAX_PORTS * 4) + 11, sizeof(*midi_function),
+ GFP_KERNEL);
+ if (!midi_function) {
+ status = -ENOMEM;
+ goto fail;
+ }
+
+ /*
+ * construct the function's descriptor set. As the number of
+ * input and output MIDI ports is configurable, we have to do
+ * it that way.
+ */
+
+ /* add the headers - these are always the same */
+ midi_function[i++] = (struct usb_descriptor_header *) &ac_interface_desc;
+ midi_function[i++] = (struct usb_descriptor_header *) &ac_header_desc;
+ midi_function[i++] = (struct usb_descriptor_header *) &ms_interface_desc;
+
+ /* calculate the header's wTotalLength */
+ n = USB_DT_MS_HEADER_SIZE
+ + (midi->in_ports + midi->out_ports) *
+ (USB_DT_MIDI_IN_SIZE + USB_DT_MIDI_OUT_SIZE(1));
+ ms_header_desc.wTotalLength = cpu_to_le16(n);
+
+ midi_function[i++] = (struct usb_descriptor_header *) &ms_header_desc;
+
+ /* configure the external IN jacks, each linked to an embedded OUT jack */
+ for (n = 0; n < midi->in_ports; n++) {
+ struct usb_midi_in_jack_descriptor *in_ext = &jack_in_ext_desc[n];
+ struct usb_midi_out_jack_descriptor_1 *out_emb = &jack_out_emb_desc[n];
+
+ in_ext->bLength = USB_DT_MIDI_IN_SIZE;
+ in_ext->bDescriptorType = USB_DT_CS_INTERFACE;
+ in_ext->bDescriptorSubtype = USB_MS_MIDI_IN_JACK;
+ in_ext->bJackType = USB_MS_EXTERNAL;
+ in_ext->bJackID = jack++;
+ in_ext->iJack = 0;
+ midi_function[i++] = (struct usb_descriptor_header *) in_ext;
+
+ out_emb->bLength = USB_DT_MIDI_OUT_SIZE(1);
+ out_emb->bDescriptorType = USB_DT_CS_INTERFACE;
+ out_emb->bDescriptorSubtype = USB_MS_MIDI_OUT_JACK;
+ out_emb->bJackType = USB_MS_EMBEDDED;
+ out_emb->bJackID = jack++;
+ out_emb->bNrInputPins = 1;
+ out_emb->pins[0].baSourcePin = 1;
+ out_emb->pins[0].baSourceID = in_ext->bJackID;
+ out_emb->iJack = 0;
+ midi_function[i++] = (struct usb_descriptor_header *) out_emb;
+
+ /* link it to the endpoint */
+ ms_in_desc.baAssocJackID[n] = out_emb->bJackID;
+ }
+
+ /* configure the external OUT jacks, each linked to an embedded IN jack */
+ for (n = 0; n < midi->out_ports; n++) {
+ struct usb_midi_in_jack_descriptor *in_emb = &jack_in_emb_desc[n];
+ struct usb_midi_out_jack_descriptor_1 *out_ext = &jack_out_ext_desc[n];
+
+ in_emb->bLength = USB_DT_MIDI_IN_SIZE;
+ in_emb->bDescriptorType = USB_DT_CS_INTERFACE;
+ in_emb->bDescriptorSubtype = USB_MS_MIDI_IN_JACK;
+ in_emb->bJackType = USB_MS_EMBEDDED;
+ in_emb->bJackID = jack++;
+ in_emb->iJack = 0;
+ midi_function[i++] = (struct usb_descriptor_header *) in_emb;
+
+ out_ext->bLength = USB_DT_MIDI_OUT_SIZE(1);
+ out_ext->bDescriptorType = USB_DT_CS_INTERFACE;
+ out_ext->bDescriptorSubtype = USB_MS_MIDI_OUT_JACK;
+ out_ext->bJackType = USB_MS_EXTERNAL;
+ out_ext->bJackID = jack++;
+ out_ext->bNrInputPins = 1;
+ out_ext->iJack = 0;
+ out_ext->pins[0].baSourceID = in_emb->bJackID;
+ out_ext->pins[0].baSourcePin = 1;
+ midi_function[i++] = (struct usb_descriptor_header *) out_ext;
+
+ /* link it to the endpoint */
+ ms_out_desc.baAssocJackID[n] = in_emb->bJackID;
+ }
+
+ /* configure the endpoint descriptors ... */
+ ms_out_desc.bLength = USB_DT_MS_ENDPOINT_SIZE(midi->in_ports);
+ ms_out_desc.bNumEmbMIDIJack = midi->in_ports;
+
+ ms_in_desc.bLength = USB_DT_MS_ENDPOINT_SIZE(midi->out_ports);
+ ms_in_desc.bNumEmbMIDIJack = midi->out_ports;
+
+ /* ... and add them to the list */
+ endpoint_descriptor_index = i;
+ midi_function[i++] = (struct usb_descriptor_header *) &bulk_out_desc;
+ midi_function[i++] = (struct usb_descriptor_header *) &ms_out_desc;
+ midi_function[i++] = (struct usb_descriptor_header *) &bulk_in_desc;
+ midi_function[i++] = (struct usb_descriptor_header *) &ms_in_desc;
+ midi_function[i++] = NULL;
+
+ /*
+ * support all relevant hardware speeds... we expect that when
+ * hardware is dual speed, all bulk-capable endpoints work at
+ * both speeds
+ */
+ /* copy descriptors, and track endpoint copies */
+ f->fs_descriptors = usb_copy_descriptors(midi_function);
+ if (!f->fs_descriptors)
+ goto fail_f_midi;
+
+ if (gadget_is_dualspeed(c->cdev->gadget)) {
+ bulk_in_desc.wMaxPacketSize = cpu_to_le16(512);
+ bulk_out_desc.wMaxPacketSize = cpu_to_le16(512);
+ f->hs_descriptors = usb_copy_descriptors(midi_function);
+ if (!f->hs_descriptors)
+ goto fail_f_midi;
+ }
+
+ if (gadget_is_superspeed(c->cdev->gadget)) {
+ bulk_in_desc.wMaxPacketSize = cpu_to_le16(1024);
+ bulk_out_desc.wMaxPacketSize = cpu_to_le16(1024);
+ i = endpoint_descriptor_index;
+ midi_function[i++] = (struct usb_descriptor_header *)
+ &bulk_out_desc;
+ midi_function[i++] = (struct usb_descriptor_header *)
+ &bulk_out_ss_comp_desc;
+ midi_function[i++] = (struct usb_descriptor_header *)
+ &ms_out_desc;
+ midi_function[i++] = (struct usb_descriptor_header *)
+ &bulk_in_desc;
+ midi_function[i++] = (struct usb_descriptor_header *)
+ &bulk_in_ss_comp_desc;
+ midi_function[i++] = (struct usb_descriptor_header *)
+ &ms_in_desc;
+ f->ss_descriptors = usb_copy_descriptors(midi_function);
+ if (!f->ss_descriptors)
+ goto fail_f_midi;
+
+ if (gadget_is_superspeed_plus(c->cdev->gadget)) {
+ f->ssp_descriptors = usb_copy_descriptors(midi_function);
+ if (!f->ssp_descriptors)
+ goto fail_f_midi;
+ }
+ }
+
+ kfree(midi_function);
+
+ return 0;
+
+fail_f_midi:
+ kfree(midi_function);
+ usb_free_all_descriptors(f);
+fail:
+ f_midi_unregister_card(midi);
+fail_register:
+ ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
+
+ return status;
+}
+
+static inline struct f_midi_opts *to_f_midi_opts(struct config_item *item)
+{
+ return container_of(to_config_group(item), struct f_midi_opts,
+ func_inst.group);
+}
+
+static void midi_attr_release(struct config_item *item)
+{
+ struct f_midi_opts *opts = to_f_midi_opts(item);
+
+ usb_put_function_instance(&opts->func_inst);
+}
+
+static struct configfs_item_operations midi_item_ops = {
+ .release = midi_attr_release,
+};
+
+#define F_MIDI_OPT(name, test_limit, limit) \
+static ssize_t f_midi_opts_##name##_show(struct config_item *item, char *page) \
+{ \
+ struct f_midi_opts *opts = to_f_midi_opts(item); \
+ int result; \
+ \
+ mutex_lock(&opts->lock); \
+ result = sprintf(page, "%d\n", opts->name); \
+ mutex_unlock(&opts->lock); \
+ \
+ return result; \
+} \
+ \
+static ssize_t f_midi_opts_##name##_store(struct config_item *item, \
+ const char *page, size_t len) \
+{ \
+ struct f_midi_opts *opts = to_f_midi_opts(item); \
+ int ret; \
+ u32 num; \
+ \
+ mutex_lock(&opts->lock); \
+ if (opts->refcnt > 1) { \
+ ret = -EBUSY; \
+ goto end; \
+ } \
+ \
+ ret = kstrtou32(page, 0, &num); \
+ if (ret) \
+ goto end; \
+ \
+ if (test_limit && num > limit) { \
+ ret = -EINVAL; \
+ goto end; \
+ } \
+ opts->name = num; \
+ ret = len; \
+ \
+end: \
+ mutex_unlock(&opts->lock); \
+ return ret; \
+} \
+ \
+CONFIGFS_ATTR(f_midi_opts_, name);
+
+F_MIDI_OPT(index, true, SNDRV_CARDS);
+F_MIDI_OPT(buflen, false, 0);
+F_MIDI_OPT(qlen, false, 0);
+F_MIDI_OPT(in_ports, true, MAX_PORTS);
+F_MIDI_OPT(out_ports, true, MAX_PORTS);
+
+static ssize_t f_midi_opts_id_show(struct config_item *item, char *page)
+{
+ struct f_midi_opts *opts = to_f_midi_opts(item);
+ int result;
+
+ mutex_lock(&opts->lock);
+ if (opts->id) {
+ result = strlcpy(page, opts->id, PAGE_SIZE);
+ } else {
+ page[0] = 0;
+ result = 0;
+ }
+
+ mutex_unlock(&opts->lock);
+
+ return result;
+}
+
+static ssize_t f_midi_opts_id_store(struct config_item *item,
+ const char *page, size_t len)
+{
+ struct f_midi_opts *opts = to_f_midi_opts(item);
+ int ret;
+ char *c;
+
+ mutex_lock(&opts->lock);
+ if (opts->refcnt > 1) {
+ ret = -EBUSY;
+ goto end;
+ }
+
+ c = kstrndup(page, len, GFP_KERNEL);
+ if (!c) {
+ ret = -ENOMEM;
+ goto end;
+ }
+ if (opts->id_allocated)
+ kfree(opts->id);
+ opts->id = c;
+ opts->id_allocated = true;
+ ret = len;
+end:
+ mutex_unlock(&opts->lock);
+ return ret;
+}
+
+CONFIGFS_ATTR(f_midi_opts_, id);
+
+static struct configfs_attribute *midi_attrs[] = {
+ &f_midi_opts_attr_index,
+ &f_midi_opts_attr_buflen,
+ &f_midi_opts_attr_qlen,
+ &f_midi_opts_attr_in_ports,
+ &f_midi_opts_attr_out_ports,
+ &f_midi_opts_attr_id,
+ NULL,
+};
+
+static const struct config_item_type midi_func_type = {
+ .ct_item_ops = &midi_item_ops,
+ .ct_attrs = midi_attrs,
+ .ct_owner = THIS_MODULE,
+};
+
+static void f_midi_free_inst(struct usb_function_instance *f)
+{
+ struct f_midi_opts *opts;
+ bool free = false;
+
+ opts = container_of(f, struct f_midi_opts, func_inst);
+
+ mutex_lock(&opts->lock);
+ if (!--opts->refcnt) {
+ free = true;
+ }
+ mutex_unlock(&opts->lock);
+
+ if (free) {
+ if (opts->id_allocated)
+ kfree(opts->id);
+ kfree(opts);
+ }
+}
+
+#ifdef CONFIG_USB_CONFIGFS_UEVENT
+extern struct device *create_function_device(char *name);
+static ssize_t alsa_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct usb_function_instance *fi_midi = dev_get_drvdata(dev);
+ struct f_midi *midi;
+
+ if (!fi_midi->f)
+ dev_warn(dev, "f_midi: function not set\n");
+
+ if (fi_midi && fi_midi->f) {
+ midi = func_to_midi(fi_midi->f);
+ if (midi->rmidi && midi->rmidi->card)
+ return sprintf(buf, "%d %d\n",
+ midi->rmidi->card->number, midi->rmidi->device);
+ }
+
+ /* print PCM card and device numbers */
+ return sprintf(buf, "%d %d\n", -1, -1);
+}
+
+static DEVICE_ATTR(alsa, S_IRUGO, alsa_show, NULL);
+
+static struct device_attribute *alsa_function_attributes[] = {
+ &dev_attr_alsa,
+ NULL
+};
+
+static int create_alsa_device(struct usb_function_instance *fi)
+{
+ struct device *dev;
+ struct device_attribute **attrs;
+ struct device_attribute *attr;
+ int err = 0;
+
+ dev = create_function_device("f_midi");
+ if (IS_ERR(dev))
+ return PTR_ERR(dev);
+
+ attrs = alsa_function_attributes;
+ if (attrs) {
+ while ((attr = *attrs++) && !err)
+ err = device_create_file(dev, attr);
+ if (err) {
+ device_destroy(dev->class, dev->devt);
+ return -EINVAL;
+ }
+ }
+ dev_set_drvdata(dev, fi);
+ return 0;
+}
+#else
+static int create_alsa_device(struct usb_function_instance *fi)
+{
+ return 0;
+}
+#endif
+
+static struct usb_function_instance *f_midi_alloc_inst(void)
+{
+ struct f_midi_opts *opts;
+
+ opts = kzalloc(sizeof(*opts), GFP_KERNEL);
+ if (!opts)
+ return ERR_PTR(-ENOMEM);
+
+ mutex_init(&opts->lock);
+ opts->func_inst.free_func_inst = f_midi_free_inst;
+ opts->index = SNDRV_DEFAULT_IDX1;
+ opts->id = SNDRV_DEFAULT_STR1;
+ opts->buflen = 512;
+ opts->qlen = 32;
+ opts->in_ports = 1;
+ opts->out_ports = 1;
+ opts->refcnt = 1;
+
+ if (create_alsa_device(&opts->func_inst)) {
+ kfree(opts);
+ return ERR_PTR(-ENODEV);
+ }
+
+ config_group_init_type_name(&opts->func_inst.group, "",
+ &midi_func_type);
+
+ return &opts->func_inst;
+}
+
+static void f_midi_free(struct usb_function *f)
+{
+ struct f_midi *midi;
+ struct f_midi_opts *opts;
+ bool free = false;
+
+ midi = func_to_midi(f);
+ opts = container_of(f->fi, struct f_midi_opts, func_inst);
+ mutex_lock(&opts->lock);
+ if (!--midi->free_ref) {
+ kfree(midi->id);
+ kfifo_free(&midi->in_req_fifo);
+ kfree(midi);
+ free = true;
+ opts->func_inst.f = NULL;
+ }
+ mutex_unlock(&opts->lock);
+
+ if (free)
+ f_midi_free_inst(&opts->func_inst);
+}
+
+static void f_midi_rmidi_free(struct snd_rawmidi *rmidi)
+{
+ f_midi_free(rmidi->private_data);
+}
+
+static void f_midi_unbind(struct usb_configuration *c, struct usb_function *f)
+{
+ struct usb_composite_dev *cdev = f->config->cdev;
+ struct f_midi *midi = func_to_midi(f);
+ struct snd_card *card;
+
+ DBG(cdev, "unbind\n");
+
+ /* just to be sure */
+ f_midi_disable(f);
+
+ card = midi->card;
+ midi->card = NULL;
+ if (card)
+ snd_card_free_when_closed(card);
+
+ usb_free_all_descriptors(f);
+}
+
+static struct usb_function *f_midi_alloc(struct usb_function_instance *fi)
+{
+ struct f_midi *midi = NULL;
+ struct f_midi_opts *opts;
+ int status, i;
+
+ opts = container_of(fi, struct f_midi_opts, func_inst);
+
+ mutex_lock(&opts->lock);
+ /* sanity check */
+ if (opts->in_ports > MAX_PORTS || opts->out_ports > MAX_PORTS) {
+ status = -EINVAL;
+ goto setup_fail;
+ }
+
+ /* allocate and initialize one new instance */
+ midi = kzalloc(struct_size(midi, in_ports_array, opts->in_ports),
+ GFP_KERNEL);
+ if (!midi) {
+ status = -ENOMEM;
+ goto setup_fail;
+ }
+
+ for (i = 0; i < opts->in_ports; i++)
+ midi->in_ports_array[i].cable = i;
+
+ /* set up ALSA midi devices */
+ midi->id = kstrdup(opts->id, GFP_KERNEL);
+ if (opts->id && !midi->id) {
+ status = -ENOMEM;
+ goto midi_free;
+ }
+ midi->in_ports = opts->in_ports;
+ midi->out_ports = opts->out_ports;
+ midi->index = opts->index;
+ midi->buflen = opts->buflen;
+ midi->qlen = opts->qlen;
+ midi->in_last_port = 0;
+ midi->free_ref = 1;
+
+ status = kfifo_alloc(&midi->in_req_fifo, midi->qlen, GFP_KERNEL);
+ if (status)
+ goto midi_free;
+
+ spin_lock_init(&midi->transmit_lock);
+
+ ++opts->refcnt;
+ mutex_unlock(&opts->lock);
+
+ midi->func.name = "gmidi function";
+ midi->func.bind = f_midi_bind;
+ midi->func.unbind = f_midi_unbind;
+ midi->func.set_alt = f_midi_set_alt;
+ midi->func.disable = f_midi_disable;
+ midi->func.free_func = f_midi_free;
+
+ fi->f = &midi->func;
+ return &midi->func;
+
+midi_free:
+ if (midi)
+ kfree(midi->id);
+ kfree(midi);
+setup_fail:
+ mutex_unlock(&opts->lock);
+
+ return ERR_PTR(status);
+}
+
+DECLARE_USB_FUNCTION_INIT(midi, f_midi_alloc_inst, f_midi_alloc);