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path: root/drivers/usb/gadget/function/f_midi.c
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Diffstat (limited to 'drivers/usb/gadget/function/f_midi.c')
-rw-r--r--drivers/usb/gadget/function/f_midi.c986
1 files changed, 986 insertions, 0 deletions
diff --git a/drivers/usb/gadget/function/f_midi.c b/drivers/usb/gadget/function/f_midi.c
new file mode 100644
index 000000000000..807b31c0edc3
--- /dev/null
+++ b/drivers/usb/gadget/function/f_midi.c
@@ -0,0 +1,986 @@
+/*
+ * 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>
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/device.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"
+
+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
+
+/*
+ * 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 f_midi *midi;
+ int active;
+ uint8_t cable;
+ uint8_t state;
+#define STATE_UNKNOWN 0
+#define STATE_1PARAM 1
+#define STATE_2PARAM_1 2
+#define STATE_2PARAM_2 3
+#define STATE_SYSEX_0 4
+#define STATE_SYSEX_1 5
+#define STATE_SYSEX_2 6
+ 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;
+
+ struct snd_rawmidi_substream *in_substream[MAX_PORTS];
+ struct snd_rawmidi_substream *out_substream[MAX_PORTS];
+ struct gmidi_in_port *in_port[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;
+};
+
+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, struct usb_request *req);
+
+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 __initdata = {
+ .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 __initdata = {
+ .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 __initdata = {
+ .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 __initdata = {
+ .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,
+};
+
+/* 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,
+};
+
+/* 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, length);
+}
+
+static void free_ep_req(struct usb_ep *ep, struct usb_request *req)
+{
+ kfree(req->buf);
+ usb_ep_free_request(ep, req);
+}
+
+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. */
+ f_midi_transmit(midi, req);
+ 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);
+
+ 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 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;
+
+ if (ep->driver_data)
+ 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);
+ struct usb_composite_dev *cdev = f->config->cdev;
+ unsigned i;
+ int err;
+
+ 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;
+
+ if (midi->out_ep->driver_data)
+ usb_ep_disable(midi->out_ep);
+
+ err = config_ep_by_speed(midi->gadget, f, midi->out_ep);
+ if (err) {
+ ERROR(cdev, "can't configure %s: %d\n",
+ midi->out_ep->name, err);
+ return err;
+ }
+
+ err = usb_ep_enable(midi->out_ep);
+ if (err) {
+ ERROR(cdev, "can't start %s: %d\n",
+ midi->out_ep->name, err);
+ return err;
+ }
+
+ midi->out_ep->driver_data = midi;
+
+ /* 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 queue req: %d\n",
+ midi->out_ep->name, 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;
+
+ 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);
+}
+
+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(card);
+
+ kfree(midi->id);
+ midi->id = NULL;
+
+ usb_free_all_descriptors(f);
+ kfree(midi);
+}
+
+static int f_midi_snd_free(struct snd_device *device)
+{
+ return 0;
+}
+
+static void f_midi_transmit_packet(struct usb_request *req, uint8_t p0,
+ uint8_t p1, uint8_t p2, uint8_t p3)
+{
+ unsigned length = req->length;
+ u8 *buf = (u8 *)req->buf + length;
+
+ buf[0] = p0;
+ buf[1] = p1;
+ buf[2] = p2;
+ buf[3] = p3;
+ req->length = length + 4;
+}
+
+/*
+ * 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 p0 = port->cable << 4;
+
+ if (b >= 0xf8) {
+ f_midi_transmit_packet(req, p0 | 0x0f, b, 0, 0);
+ } else if (b >= 0xf0) {
+ switch (b) {
+ case 0xf0:
+ port->data[0] = b;
+ port->state = STATE_SYSEX_1;
+ break;
+ case 0xf1:
+ case 0xf3:
+ port->data[0] = b;
+ port->state = STATE_1PARAM;
+ break;
+ case 0xf2:
+ port->data[0] = b;
+ port->state = STATE_2PARAM_1;
+ break;
+ case 0xf4:
+ case 0xf5:
+ port->state = STATE_UNKNOWN;
+ break;
+ case 0xf6:
+ f_midi_transmit_packet(req, p0 | 0x05, 0xf6, 0, 0);
+ port->state = STATE_UNKNOWN;
+ break;
+ case 0xf7:
+ switch (port->state) {
+ case STATE_SYSEX_0:
+ f_midi_transmit_packet(req,
+ p0 | 0x05, 0xf7, 0, 0);
+ break;
+ case STATE_SYSEX_1:
+ f_midi_transmit_packet(req,
+ p0 | 0x06, port->data[0], 0xf7, 0);
+ break;
+ case STATE_SYSEX_2:
+ f_midi_transmit_packet(req,
+ p0 | 0x07, port->data[0],
+ port->data[1], 0xf7);
+ break;
+ }
+ port->state = STATE_UNKNOWN;
+ break;
+ }
+ } else if (b >= 0x80) {
+ port->data[0] = b;
+ if (b >= 0xc0 && b <= 0xdf)
+ port->state = STATE_1PARAM;
+ else
+ port->state = STATE_2PARAM_1;
+ } else { /* b < 0x80 */
+ switch (port->state) {
+ case STATE_1PARAM:
+ if (port->data[0] < 0xf0) {
+ p0 |= port->data[0] >> 4;
+ } else {
+ p0 |= 0x02;
+ port->state = STATE_UNKNOWN;
+ }
+ f_midi_transmit_packet(req, p0, port->data[0], b, 0);
+ break;
+ case STATE_2PARAM_1:
+ port->data[1] = b;
+ port->state = STATE_2PARAM_2;
+ break;
+ case STATE_2PARAM_2:
+ if (port->data[0] < 0xf0) {
+ p0 |= port->data[0] >> 4;
+ port->state = STATE_2PARAM_1;
+ } else {
+ p0 |= 0x03;
+ port->state = STATE_UNKNOWN;
+ }
+ f_midi_transmit_packet(req,
+ p0, port->data[0], port->data[1], b);
+ break;
+ case STATE_SYSEX_0:
+ port->data[0] = b;
+ port->state = STATE_SYSEX_1;
+ break;
+ case STATE_SYSEX_1:
+ port->data[1] = b;
+ port->state = STATE_SYSEX_2;
+ break;
+ case STATE_SYSEX_2:
+ f_midi_transmit_packet(req,
+ p0 | 0x04, port->data[0], port->data[1], b);
+ port->state = STATE_SYSEX_0;
+ break;
+ }
+ }
+}
+
+static void f_midi_transmit(struct f_midi *midi, struct usb_request *req)
+{
+ struct usb_ep *ep = midi->in_ep;
+ int i;
+
+ if (!ep)
+ return;
+
+ if (!req)
+ req = midi_alloc_ep_req(ep, midi->buflen);
+
+ if (!req) {
+ ERROR(midi, "gmidi_transmit: alloc_ep_request failed\n");
+ return;
+ }
+ req->length = 0;
+ req->complete = f_midi_complete;
+
+ for (i = 0; i < MAX_PORTS; i++) {
+ struct gmidi_in_port *port = midi->in_port[i];
+ struct snd_rawmidi_substream *substream = midi->in_substream[i];
+
+ if (!port || !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);
+ }
+ }
+
+ if (req->length > 0)
+ usb_ep_queue(ep, req, GFP_ATOMIC);
+ else
+ free_ep_req(ep, req);
+}
+
+static void f_midi_in_tasklet(unsigned long data)
+{
+ struct f_midi *midi = (struct f_midi *) data;
+ f_midi_transmit(midi, NULL);
+}
+
+static int f_midi_in_open(struct snd_rawmidi_substream *substream)
+{
+ struct f_midi *midi = substream->rmidi->private_data;
+
+ if (!midi->in_port[substream->number])
+ return -EINVAL;
+
+ VDBG(midi, "%s()\n", __func__);
+ midi->in_substream[substream->number] = substream;
+ midi->in_port[substream->number]->state = STATE_UNKNOWN;
+ 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 (!midi->in_port[substream->number])
+ return;
+
+ VDBG(midi, "%s() %d\n", __func__, up);
+ midi->in_port[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 struct snd_rawmidi_ops gmidi_in_ops = {
+ .open = f_midi_in_open,
+ .close = f_midi_in_close,
+ .trigger = f_midi_in_trigger,
+};
+
+static struct snd_rawmidi_ops gmidi_out_ops = {
+ .open = f_midi_out_open,
+ .close = f_midi_out_close,
+ .trigger = f_midi_out_trigger
+};
+
+/* 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;
+ strcpy(rmidi->name, card->shortname);
+ rmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
+ SNDRV_RAWMIDI_INFO_INPUT |
+ SNDRV_RAWMIDI_INFO_DUPLEX;
+ rmidi->private_data = midi;
+
+ /*
+ * 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:
+ if (midi->card) {
+ snd_card_free(midi->card);
+ midi->card = NULL;
+ }
+ return err;
+}
+
+/* MIDI function driver setup/binding */
+
+static int __init
+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);
+ int status, n, jack = 1, i = 0;
+
+ /* maybe allocate device-global string ID */
+ if (midi_string_defs[0].id == 0) {
+ status = usb_string_id(c->cdev);
+ if (status < 0)
+ goto fail;
+ midi_string_defs[0].id = status;
+ }
+
+ /* 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;
+
+ status = -ENODEV;
+
+ /* allocate instance-specific endpoints */
+ midi->in_ep = usb_ep_autoconfig(cdev->gadget, &bulk_in_desc);
+ if (!midi->in_ep)
+ goto fail;
+ midi->in_ep->driver_data = cdev; /* claim */
+
+ midi->out_ep = usb_ep_autoconfig(cdev->gadget, &bulk_out_desc);
+ if (!midi->out_ep)
+ goto fail;
+ midi->out_ep->driver_data = cdev; /* claim */
+
+ /* allocate temporary function list */
+ midi_function = kcalloc((MAX_PORTS * 4) + 9, 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 */
+ 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;
+ }
+
+ kfree(midi_function);
+
+ return 0;
+
+fail_f_midi:
+ kfree(midi_function);
+ usb_free_descriptors(f->hs_descriptors);
+fail:
+ /* we might as well release our claims on endpoints */
+ if (midi->out_ep)
+ midi->out_ep->driver_data = NULL;
+ if (midi->in_ep)
+ midi->in_ep->driver_data = NULL;
+
+ ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
+
+ return status;
+}
+
+/**
+ * f_midi_bind_config - add USB MIDI function to a configuration
+ * @c: the configuration to supcard the USB audio function
+ * @index: the soundcard index to use for the ALSA device creation
+ * @id: the soundcard id to use for the ALSA device creation
+ * @buflen: the buffer length to use
+ * @qlen the number of read requests to pre-allocate
+ * Context: single threaded during gadget setup
+ *
+ * Returns zero on success, else negative errno.
+ */
+int __init f_midi_bind_config(struct usb_configuration *c,
+ int index, char *id,
+ unsigned int in_ports,
+ unsigned int out_ports,
+ unsigned int buflen,
+ unsigned int qlen)
+{
+ struct f_midi *midi;
+ int status, i;
+
+ /* sanity check */
+ if (in_ports > MAX_PORTS || out_ports > MAX_PORTS)
+ return -EINVAL;
+
+ /* allocate and initialize one new instance */
+ midi = kzalloc(sizeof *midi, GFP_KERNEL);
+ if (!midi) {
+ status = -ENOMEM;
+ goto fail;
+ }
+
+ for (i = 0; i < in_ports; i++) {
+ struct gmidi_in_port *port = kzalloc(sizeof(*port), GFP_KERNEL);
+ if (!port) {
+ status = -ENOMEM;
+ goto setup_fail;
+ }
+
+ port->midi = midi;
+ port->active = 0;
+ port->cable = i;
+ midi->in_port[i] = port;
+ }
+
+ midi->gadget = c->cdev->gadget;
+ tasklet_init(&midi->tasklet, f_midi_in_tasklet, (unsigned long) midi);
+
+ /* set up ALSA midi devices */
+ midi->in_ports = in_ports;
+ midi->out_ports = out_ports;
+ status = f_midi_register_card(midi);
+ if (status < 0)
+ goto setup_fail;
+
+ midi->func.name = "gmidi function";
+ midi->func.strings = midi_strings;
+ 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->id = kstrdup(id, GFP_KERNEL);
+ midi->index = index;
+ midi->buflen = buflen;
+ midi->qlen = qlen;
+
+ status = usb_add_function(c, &midi->func);
+ if (status)
+ goto setup_fail;
+
+ return 0;
+
+setup_fail:
+ for (--i; i >= 0; i--)
+ kfree(midi->in_port[i]);
+ kfree(midi);
+fail:
+ return status;
+}
+