diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/usb/gadget/f_midi.c | 923 |
1 files changed, 923 insertions, 0 deletions
diff --git a/drivers/usb/gadget/f_midi.c b/drivers/usb/gadget/f_midi.c new file mode 100644 index 000000000000..5064ea4efbed --- /dev/null +++ b/drivers/usb/gadget/f_midi.c @@ -0,0 +1,923 @@ +/* + * 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/utsname.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> + +MODULE_AUTHOR("Ben Williamson"); +MODULE_LICENSE("GPL v2"); + +static const char f_midi_shortname[] = "f_midi"; +static const char f_midi_longname[] = "MIDI Gadget"; + +/* + * 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; /* cable number << 4 */ + 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; + struct snd_rawmidi_substream *out_substream; + + /* For the moment we only support one port in + each direction, but in_port is kept as a + separate struct so we can have more later. */ + struct gmidi_in_port in_port; + unsigned long out_triggered; + struct tasklet_struct tasklet; + 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(1); + +/* 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 = cpu_to_le16(USB_DT_MS_HEADER_SIZE + + 2*USB_DT_MIDI_IN_SIZE + + 2*USB_DT_MIDI_OUT_SIZE(1)), +}; + +#define JACK_IN_EMB 1 +#define JACK_IN_EXT 2 +#define JACK_OUT_EMB 3 +#define JACK_OUT_EXT 4 + +/* B.4.3 MIDI IN Jack Descriptors */ +static const struct usb_midi_in_jack_descriptor jack_in_emb_desc = { + .bLength = USB_DT_MIDI_IN_SIZE, + .bDescriptorType = USB_DT_CS_INTERFACE, + .bDescriptorSubtype = USB_MS_MIDI_IN_JACK, + .bJackType = USB_MS_EMBEDDED, + .bJackID = JACK_IN_EMB, +}; + +static const struct usb_midi_in_jack_descriptor jack_in_ext_desc = { + .bLength = USB_DT_MIDI_IN_SIZE, + .bDescriptorType = USB_DT_CS_INTERFACE, + .bDescriptorSubtype = USB_MS_MIDI_IN_JACK, + .bJackType = USB_MS_EXTERNAL, + .bJackID = JACK_IN_EXT, +}; + +/* B.4.4 MIDI OUT Jack Descriptors */ +static const struct usb_midi_out_jack_descriptor_1 jack_out_emb_desc = { + .bLength = USB_DT_MIDI_OUT_SIZE(1), + .bDescriptorType = USB_DT_CS_INTERFACE, + .bDescriptorSubtype = USB_MS_MIDI_OUT_JACK, + .bJackType = USB_MS_EMBEDDED, + .bJackID = JACK_OUT_EMB, + .bNrInputPins = 1, + .pins = { + [0] = { + .baSourceID = JACK_IN_EXT, + .baSourcePin = 1, + } + } +}; + +static const struct usb_midi_out_jack_descriptor_1 jack_out_ext_desc = { + .bLength = USB_DT_MIDI_OUT_SIZE(1), + .bDescriptorType = USB_DT_CS_INTERFACE, + .bDescriptorSubtype = USB_MS_MIDI_OUT_JACK, + .bJackType = USB_MS_EXTERNAL, + .bJackID = JACK_OUT_EXT, + .bNrInputPins = 1, + .pins = { + [0] = { + .baSourceID = JACK_IN_EMB, + .baSourcePin = 1, + } + } +}; + +/* 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 const struct usb_ms_endpoint_descriptor_1 ms_out_desc = { + .bLength = USB_DT_MS_ENDPOINT_SIZE(1), + .bDescriptorType = USB_DT_CS_ENDPOINT, + .bDescriptorSubtype = USB_MS_GENERAL, + .bNumEmbMIDIJack = 1, + .baAssocJackID = { + [0] = JACK_IN_EMB, + } +}; + +/* 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 const struct usb_ms_endpoint_descriptor_1 ms_in_desc = { + .bLength = USB_DT_MS_ENDPOINT_SIZE(1), + .bDescriptorType = USB_DT_CS_ENDPOINT, + .bDescriptorSubtype = USB_MS_GENERAL, + .bNumEmbMIDIJack = 1, + .baAssocJackID = { + [0] = JACK_OUT_EMB, + } +}; + +static struct usb_descriptor_header *midi_function[] = { + (struct usb_descriptor_header *)&ac_interface_desc, + (struct usb_descriptor_header *)&ac_header_desc, + (struct usb_descriptor_header *)&ms_interface_desc, + + (struct usb_descriptor_header *)&ms_header_desc, + (struct usb_descriptor_header *)&jack_in_emb_desc, + (struct usb_descriptor_header *)&jack_in_ext_desc, + (struct usb_descriptor_header *)&jack_out_emb_desc, + (struct usb_descriptor_header *)&jack_out_ext_desc, + /* If you add more jacks, update ms_header_desc.wTotalLength */ + + (struct usb_descriptor_header *)&bulk_out_desc, + (struct usb_descriptor_header *)&ms_out_desc, + (struct usb_descriptor_header *)&bulk_in_desc, + (struct usb_descriptor_header *)&ms_in_desc, + NULL, +}; + +/* 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 struct usb_request *alloc_ep_req(struct usb_ep *ep, unsigned length) +{ + struct usb_request *req; + + req = usb_ep_alloc_request(ep, GFP_ATOMIC); + if (req) { + req->length = length; + req->buf = kmalloc(length, GFP_ATOMIC); + if (!req->buf) { + usb_ep_free_request(ep, req); + req = NULL; + } + } + return req; +} + +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; + /* cable is ignored, because for now we only have one. */ + + if (!midi->out_substream) + /* Nobody is listening - throw it on the floor. */ + return; + + if (!test_bit(midi->out_substream->number, &midi->out_triggered)) + return; + + snd_rawmidi_receive(midi->out_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 = + 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_descriptors(f->descriptors); + 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; + + 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; + struct gmidi_in_port *port = &midi->in_port; + + if (!ep) + return; + + if (!req) + req = 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; + + if (port->active) { + while (req->length + 3 < midi->buflen) { + uint8_t b; + if (snd_rawmidi_transmit(midi->in_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; + + VDBG(midi, "%s()\n", __func__); + midi->in_substream = substream; + midi->in_port.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; + + VDBG(midi, "%s() %d\n", __func__, up); + midi->in_port.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; + + VDBG(midi, "%s()\n", __func__); + midi->out_substream = 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; + int out_ports = 1; + int in_ports = 1; + static struct snd_device_ops ops = { + .dev_free = f_midi_snd_free, + }; + + err = snd_card_create(midi->index, midi->id, THIS_MODULE, 0, &card); + if (err < 0) { + ERROR(midi, "snd_card_create() 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 */ + midi->in_port.midi = midi; + midi->in_port.active = 0; + snd_component_add(card, "MIDI"); + err = snd_rawmidi_new(card, card->longname, 0, + out_ports, 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); + + snd_card_set_dev(card, &midi->gadget->dev); + + /* 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_composite_dev *cdev = c->cdev; + struct f_midi *midi = func_to_midi(f); + int status; + + /* 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 */ + + /* + * 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 */ + if (gadget_is_dualspeed(c->cdev->gadget)) { + c->highspeed = true; + bulk_in_desc.wMaxPacketSize = cpu_to_le16(512); + bulk_out_desc.wMaxPacketSize = cpu_to_le16(512); + f->hs_descriptors = usb_copy_descriptors(midi_function); + } else { + f->descriptors = usb_copy_descriptors(midi_function); + } + + return 0; + +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 buflen, + unsigned int qlen) +{ + struct f_midi *midi; + int status; + + /* allocate and initialize one new instance */ + midi = kzalloc(sizeof *midi, GFP_KERNEL); + if (!midi) { + status = -ENOMEM; + goto fail; + } + + midi->gadget = c->cdev->gadget; + tasklet_init(&midi->tasklet, f_midi_in_tasklet, (unsigned long) midi); + + /* set up ALSA midi devices */ + 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: + kfree(midi); +fail: + return status; +} + |