diff options
Diffstat (limited to 'drivers/usb/gadget/f_uac1.c')
| -rw-r--r-- | drivers/usb/gadget/f_uac1.c | 776 |
1 files changed, 776 insertions, 0 deletions
diff --git a/drivers/usb/gadget/f_uac1.c b/drivers/usb/gadget/f_uac1.c new file mode 100644 index 000000000000..1a5dcd5565e3 --- /dev/null +++ b/drivers/usb/gadget/f_uac1.c @@ -0,0 +1,776 @@ +/* + * f_audio.c -- USB Audio class function driver + * + * Copyright (C) 2008 Bryan Wu <cooloney@kernel.org> + * Copyright (C) 2008 Analog Devices, Inc + * + * Enter bugs at http://blackfin.uclinux.org/ + * + * Licensed under the GPL-2 or later. + */ + +#include <linux/slab.h> +#include <linux/kernel.h> +#include <linux/device.h> +#include <linux/atomic.h> + +#include "u_uac1.h" + +#define OUT_EP_MAX_PACKET_SIZE 200 +static int req_buf_size = OUT_EP_MAX_PACKET_SIZE; +module_param(req_buf_size, int, S_IRUGO); +MODULE_PARM_DESC(req_buf_size, "ISO OUT endpoint request buffer size"); + +static int req_count = 256; +module_param(req_count, int, S_IRUGO); +MODULE_PARM_DESC(req_count, "ISO OUT endpoint request count"); + +static int audio_buf_size = 48000; +module_param(audio_buf_size, int, S_IRUGO); +MODULE_PARM_DESC(audio_buf_size, "Audio buffer size"); + +static int generic_set_cmd(struct usb_audio_control *con, u8 cmd, int value); +static int generic_get_cmd(struct usb_audio_control *con, u8 cmd); + +/* + * DESCRIPTORS ... most are static, but strings and full + * configuration descriptors are built on demand. + */ + +/* + * We have two interfaces- AudioControl and AudioStreaming + * TODO: only supcard playback currently + */ +#define F_AUDIO_AC_INTERFACE 0 +#define F_AUDIO_AS_INTERFACE 1 +#define F_AUDIO_NUM_INTERFACES 2 + +/* 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, + .bNumEndpoints = 0, + .bInterfaceClass = USB_CLASS_AUDIO, + .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL, +}; + +DECLARE_UAC_AC_HEADER_DESCRIPTOR(2); + +#define UAC_DT_AC_HEADER_LENGTH UAC_DT_AC_HEADER_SIZE(F_AUDIO_NUM_INTERFACES) +/* 1 input terminal, 1 output terminal and 1 feature unit */ +#define UAC_DT_TOTAL_LENGTH (UAC_DT_AC_HEADER_LENGTH + UAC_DT_INPUT_TERMINAL_SIZE \ + + UAC_DT_OUTPUT_TERMINAL_SIZE + UAC_DT_FEATURE_UNIT_SIZE(0)) +/* B.3.2 Class-Specific AC Interface Descriptor */ +static struct uac1_ac_header_descriptor_2 ac_header_desc = { + .bLength = UAC_DT_AC_HEADER_LENGTH, + .bDescriptorType = USB_DT_CS_INTERFACE, + .bDescriptorSubtype = UAC_HEADER, + .bcdADC = __constant_cpu_to_le16(0x0100), + .wTotalLength = __constant_cpu_to_le16(UAC_DT_TOTAL_LENGTH), + .bInCollection = F_AUDIO_NUM_INTERFACES, + .baInterfaceNr = { + [0] = F_AUDIO_AC_INTERFACE, + [1] = F_AUDIO_AS_INTERFACE, + } +}; + +#define INPUT_TERMINAL_ID 1 +static struct uac_input_terminal_descriptor input_terminal_desc = { + .bLength = UAC_DT_INPUT_TERMINAL_SIZE, + .bDescriptorType = USB_DT_CS_INTERFACE, + .bDescriptorSubtype = UAC_INPUT_TERMINAL, + .bTerminalID = INPUT_TERMINAL_ID, + .wTerminalType = UAC_TERMINAL_STREAMING, + .bAssocTerminal = 0, + .wChannelConfig = 0x3, +}; + +DECLARE_UAC_FEATURE_UNIT_DESCRIPTOR(0); + +#define FEATURE_UNIT_ID 2 +static struct uac_feature_unit_descriptor_0 feature_unit_desc = { + .bLength = UAC_DT_FEATURE_UNIT_SIZE(0), + .bDescriptorType = USB_DT_CS_INTERFACE, + .bDescriptorSubtype = UAC_FEATURE_UNIT, + .bUnitID = FEATURE_UNIT_ID, + .bSourceID = INPUT_TERMINAL_ID, + .bControlSize = 2, + .bmaControls[0] = (UAC_FU_MUTE | UAC_FU_VOLUME), +}; + +static struct usb_audio_control mute_control = { + .list = LIST_HEAD_INIT(mute_control.list), + .name = "Mute Control", + .type = UAC_FU_MUTE, + /* Todo: add real Mute control code */ + .set = generic_set_cmd, + .get = generic_get_cmd, +}; + +static struct usb_audio_control volume_control = { + .list = LIST_HEAD_INIT(volume_control.list), + .name = "Volume Control", + .type = UAC_FU_VOLUME, + /* Todo: add real Volume control code */ + .set = generic_set_cmd, + .get = generic_get_cmd, +}; + +static struct usb_audio_control_selector feature_unit = { + .list = LIST_HEAD_INIT(feature_unit.list), + .id = FEATURE_UNIT_ID, + .name = "Mute & Volume Control", + .type = UAC_FEATURE_UNIT, + .desc = (struct usb_descriptor_header *)&feature_unit_desc, +}; + +#define OUTPUT_TERMINAL_ID 3 +static struct uac1_output_terminal_descriptor output_terminal_desc = { + .bLength = UAC_DT_OUTPUT_TERMINAL_SIZE, + .bDescriptorType = USB_DT_CS_INTERFACE, + .bDescriptorSubtype = UAC_OUTPUT_TERMINAL, + .bTerminalID = OUTPUT_TERMINAL_ID, + .wTerminalType = UAC_OUTPUT_TERMINAL_SPEAKER, + .bAssocTerminal = FEATURE_UNIT_ID, + .bSourceID = FEATURE_UNIT_ID, +}; + +/* B.4.1 Standard AS Interface Descriptor */ +static struct usb_interface_descriptor as_interface_alt_0_desc = { + .bLength = USB_DT_INTERFACE_SIZE, + .bDescriptorType = USB_DT_INTERFACE, + .bAlternateSetting = 0, + .bNumEndpoints = 0, + .bInterfaceClass = USB_CLASS_AUDIO, + .bInterfaceSubClass = USB_SUBCLASS_AUDIOSTREAMING, +}; + +static struct usb_interface_descriptor as_interface_alt_1_desc = { + .bLength = USB_DT_INTERFACE_SIZE, + .bDescriptorType = USB_DT_INTERFACE, + .bAlternateSetting = 1, + .bNumEndpoints = 1, + .bInterfaceClass = USB_CLASS_AUDIO, + .bInterfaceSubClass = USB_SUBCLASS_AUDIOSTREAMING, +}; + +/* B.4.2 Class-Specific AS Interface Descriptor */ +static struct uac1_as_header_descriptor as_header_desc = { + .bLength = UAC_DT_AS_HEADER_SIZE, + .bDescriptorType = USB_DT_CS_INTERFACE, + .bDescriptorSubtype = UAC_AS_GENERAL, + .bTerminalLink = INPUT_TERMINAL_ID, + .bDelay = 1, + .wFormatTag = UAC_FORMAT_TYPE_I_PCM, +}; + +DECLARE_UAC_FORMAT_TYPE_I_DISCRETE_DESC(1); + +static struct uac_format_type_i_discrete_descriptor_1 as_type_i_desc = { + .bLength = UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(1), + .bDescriptorType = USB_DT_CS_INTERFACE, + .bDescriptorSubtype = UAC_FORMAT_TYPE, + .bFormatType = UAC_FORMAT_TYPE_I, + .bSubframeSize = 2, + .bBitResolution = 16, + .bSamFreqType = 1, +}; + +/* Standard ISO OUT Endpoint Descriptor */ +static struct usb_endpoint_descriptor as_out_ep_desc = { + .bLength = USB_DT_ENDPOINT_AUDIO_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + .bEndpointAddress = USB_DIR_OUT, + .bmAttributes = USB_ENDPOINT_SYNC_ADAPTIVE + | USB_ENDPOINT_XFER_ISOC, + .wMaxPacketSize = __constant_cpu_to_le16(OUT_EP_MAX_PACKET_SIZE), + .bInterval = 4, +}; + +/* Class-specific AS ISO OUT Endpoint Descriptor */ +static struct uac_iso_endpoint_descriptor as_iso_out_desc __initdata = { + .bLength = UAC_ISO_ENDPOINT_DESC_SIZE, + .bDescriptorType = USB_DT_CS_ENDPOINT, + .bDescriptorSubtype = UAC_EP_GENERAL, + .bmAttributes = 1, + .bLockDelayUnits = 1, + .wLockDelay = __constant_cpu_to_le16(1), +}; + +static struct usb_descriptor_header *f_audio_desc[] __initdata = { + (struct usb_descriptor_header *)&ac_interface_desc, + (struct usb_descriptor_header *)&ac_header_desc, + + (struct usb_descriptor_header *)&input_terminal_desc, + (struct usb_descriptor_header *)&output_terminal_desc, + (struct usb_descriptor_header *)&feature_unit_desc, + + (struct usb_descriptor_header *)&as_interface_alt_0_desc, + (struct usb_descriptor_header *)&as_interface_alt_1_desc, + (struct usb_descriptor_header *)&as_header_desc, + + (struct usb_descriptor_header *)&as_type_i_desc, + + (struct usb_descriptor_header *)&as_out_ep_desc, + (struct usb_descriptor_header *)&as_iso_out_desc, + NULL, +}; + +/* + * This function is an ALSA sound card following USB Audio Class Spec 1.0. + */ + +/*-------------------------------------------------------------------------*/ +struct f_audio_buf { + u8 *buf; + int actual; + struct list_head list; +}; + +static struct f_audio_buf *f_audio_buffer_alloc(int buf_size) +{ + struct f_audio_buf *copy_buf; + + copy_buf = kzalloc(sizeof *copy_buf, GFP_ATOMIC); + if (!copy_buf) + return ERR_PTR(-ENOMEM); + + copy_buf->buf = kzalloc(buf_size, GFP_ATOMIC); + if (!copy_buf->buf) { + kfree(copy_buf); + return ERR_PTR(-ENOMEM); + } + + return copy_buf; +} + +static void f_audio_buffer_free(struct f_audio_buf *audio_buf) +{ + kfree(audio_buf->buf); + kfree(audio_buf); +} +/*-------------------------------------------------------------------------*/ + +struct f_audio { + struct gaudio card; + + /* endpoints handle full and/or high speeds */ + struct usb_ep *out_ep; + + spinlock_t lock; + struct f_audio_buf *copy_buf; + struct work_struct playback_work; + struct list_head play_queue; + + /* Control Set command */ + struct list_head cs; + u8 set_cmd; + struct usb_audio_control *set_con; +}; + +static inline struct f_audio *func_to_audio(struct usb_function *f) +{ + return container_of(f, struct f_audio, card.func); +} + +/*-------------------------------------------------------------------------*/ + +static void f_audio_playback_work(struct work_struct *data) +{ + struct f_audio *audio = container_of(data, struct f_audio, + playback_work); + struct f_audio_buf *play_buf; + + spin_lock_irq(&audio->lock); + if (list_empty(&audio->play_queue)) { + spin_unlock_irq(&audio->lock); + return; + } + play_buf = list_first_entry(&audio->play_queue, + struct f_audio_buf, list); + list_del(&play_buf->list); + spin_unlock_irq(&audio->lock); + + u_audio_playback(&audio->card, play_buf->buf, play_buf->actual); + f_audio_buffer_free(play_buf); +} + +static int f_audio_out_ep_complete(struct usb_ep *ep, struct usb_request *req) +{ + struct f_audio *audio = req->context; + struct usb_composite_dev *cdev = audio->card.func.config->cdev; + struct f_audio_buf *copy_buf = audio->copy_buf; + int err; + + if (!copy_buf) + return -EINVAL; + + /* Copy buffer is full, add it to the play_queue */ + if (audio_buf_size - copy_buf->actual < req->actual) { + list_add_tail(©_buf->list, &audio->play_queue); + schedule_work(&audio->playback_work); + copy_buf = f_audio_buffer_alloc(audio_buf_size); + if (IS_ERR(copy_buf)) + return -ENOMEM; + } + + memcpy(copy_buf->buf + copy_buf->actual, req->buf, req->actual); + copy_buf->actual += req->actual; + audio->copy_buf = copy_buf; + + err = usb_ep_queue(ep, req, GFP_ATOMIC); + if (err) + ERROR(cdev, "%s queue req: %d\n", ep->name, err); + + return 0; + +} + +static void f_audio_complete(struct usb_ep *ep, struct usb_request *req) +{ + struct f_audio *audio = req->context; + int status = req->status; + u32 data = 0; + struct usb_ep *out_ep = audio->out_ep; + + switch (status) { + + case 0: /* normal completion? */ + if (ep == out_ep) + f_audio_out_ep_complete(ep, req); + else if (audio->set_con) { + memcpy(&data, req->buf, req->length); + audio->set_con->set(audio->set_con, audio->set_cmd, + le16_to_cpu(data)); + audio->set_con = NULL; + } + break; + default: + break; + } +} + +static int audio_set_intf_req(struct usb_function *f, + const struct usb_ctrlrequest *ctrl) +{ + struct f_audio *audio = func_to_audio(f); + struct usb_composite_dev *cdev = f->config->cdev; + struct usb_request *req = cdev->req; + u8 id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF); + u16 len = le16_to_cpu(ctrl->wLength); + u16 w_value = le16_to_cpu(ctrl->wValue); + u8 con_sel = (w_value >> 8) & 0xFF; + u8 cmd = (ctrl->bRequest & 0x0F); + struct usb_audio_control_selector *cs; + struct usb_audio_control *con; + + DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n", + ctrl->bRequest, w_value, len, id); + + list_for_each_entry(cs, &audio->cs, list) { + if (cs->id == id) { + list_for_each_entry(con, &cs->control, list) { + if (con->type == con_sel) { + audio->set_con = con; + break; + } + } + break; + } + } + + audio->set_cmd = cmd; + req->context = audio; + req->complete = f_audio_complete; + + return len; +} + +static int audio_get_intf_req(struct usb_function *f, + const struct usb_ctrlrequest *ctrl) +{ + struct f_audio *audio = func_to_audio(f); + struct usb_composite_dev *cdev = f->config->cdev; + struct usb_request *req = cdev->req; + int value = -EOPNOTSUPP; + u8 id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF); + u16 len = le16_to_cpu(ctrl->wLength); + u16 w_value = le16_to_cpu(ctrl->wValue); + u8 con_sel = (w_value >> 8) & 0xFF; + u8 cmd = (ctrl->bRequest & 0x0F); + struct usb_audio_control_selector *cs; + struct usb_audio_control *con; + + DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n", + ctrl->bRequest, w_value, len, id); + + list_for_each_entry(cs, &audio->cs, list) { + if (cs->id == id) { + list_for_each_entry(con, &cs->control, list) { + if (con->type == con_sel && con->get) { + value = con->get(con, cmd); + break; + } + } + break; + } + } + + req->context = audio; + req->complete = f_audio_complete; + memcpy(req->buf, &value, len); + + return len; +} + +static int audio_set_endpoint_req(struct usb_function *f, + const struct usb_ctrlrequest *ctrl) +{ + struct usb_composite_dev *cdev = f->config->cdev; + int value = -EOPNOTSUPP; + u16 ep = le16_to_cpu(ctrl->wIndex); + u16 len = le16_to_cpu(ctrl->wLength); + u16 w_value = le16_to_cpu(ctrl->wValue); + + DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n", + ctrl->bRequest, w_value, len, ep); + + switch (ctrl->bRequest) { + case UAC_SET_CUR: + value = len; + break; + + case UAC_SET_MIN: + break; + + case UAC_SET_MAX: + break; + + case UAC_SET_RES: + break; + + case UAC_SET_MEM: + break; + + default: + break; + } + + return value; +} + +static int audio_get_endpoint_req(struct usb_function *f, + const struct usb_ctrlrequest *ctrl) +{ + struct usb_composite_dev *cdev = f->config->cdev; + int value = -EOPNOTSUPP; + u8 ep = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF); + u16 len = le16_to_cpu(ctrl->wLength); + u16 w_value = le16_to_cpu(ctrl->wValue); + + DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n", + ctrl->bRequest, w_value, len, ep); + + switch (ctrl->bRequest) { + case UAC_GET_CUR: + case UAC_GET_MIN: + case UAC_GET_MAX: + case UAC_GET_RES: + value = len; + break; + case UAC_GET_MEM: + break; + default: + break; + } + + return value; +} + +static int +f_audio_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl) +{ + struct usb_composite_dev *cdev = f->config->cdev; + struct usb_request *req = cdev->req; + int value = -EOPNOTSUPP; + u16 w_index = le16_to_cpu(ctrl->wIndex); + u16 w_value = le16_to_cpu(ctrl->wValue); + u16 w_length = le16_to_cpu(ctrl->wLength); + + /* composite driver infrastructure handles everything; interface + * activation uses set_alt(). + */ + switch (ctrl->bRequestType) { + case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE: + value = audio_set_intf_req(f, ctrl); + break; + + case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE: + value = audio_get_intf_req(f, ctrl); + break; + + case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_ENDPOINT: + value = audio_set_endpoint_req(f, ctrl); + break; + + case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT: + value = audio_get_endpoint_req(f, ctrl); + break; + + default: + ERROR(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n", + ctrl->bRequestType, ctrl->bRequest, + w_value, w_index, w_length); + } + + /* respond with data transfer or status phase? */ + if (value >= 0) { + DBG(cdev, "audio req%02x.%02x v%04x i%04x l%d\n", + ctrl->bRequestType, ctrl->bRequest, + w_value, w_index, w_length); + req->zero = 0; + req->length = value; + value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC); + if (value < 0) + ERROR(cdev, "audio response on err %d\n", value); + } + + /* device either stalls (value < 0) or reports success */ + return value; +} + +static int f_audio_set_alt(struct usb_function *f, unsigned intf, unsigned alt) +{ + struct f_audio *audio = func_to_audio(f); + struct usb_composite_dev *cdev = f->config->cdev; + struct usb_ep *out_ep = audio->out_ep; + struct usb_request *req; + int i = 0, err = 0; + + DBG(cdev, "intf %d, alt %d\n", intf, alt); + + if (intf == 1) { + if (alt == 1) { + usb_ep_enable(out_ep); + out_ep->driver_data = audio; + audio->copy_buf = f_audio_buffer_alloc(audio_buf_size); + if (IS_ERR(audio->copy_buf)) + return -ENOMEM; + + /* + * allocate a bunch of read buffers + * and queue them all at once. + */ + for (i = 0; i < req_count && err == 0; i++) { + req = usb_ep_alloc_request(out_ep, GFP_ATOMIC); + if (req) { + req->buf = kzalloc(req_buf_size, + GFP_ATOMIC); + if (req->buf) { + req->length = req_buf_size; + req->context = audio; + req->complete = + f_audio_complete; + err = usb_ep_queue(out_ep, + req, GFP_ATOMIC); + if (err) + ERROR(cdev, + "%s queue req: %d\n", + out_ep->name, err); + } else + err = -ENOMEM; + } else + err = -ENOMEM; + } + + } else { + struct f_audio_buf *copy_buf = audio->copy_buf; + if (copy_buf) { + list_add_tail(©_buf->list, + &audio->play_queue); + schedule_work(&audio->playback_work); + } + } + } + + return err; +} + +static void f_audio_disable(struct usb_function *f) +{ + return; +} + +/*-------------------------------------------------------------------------*/ + +static void f_audio_build_desc(struct f_audio *audio) +{ + struct gaudio *card = &audio->card; + u8 *sam_freq; + int rate; + + /* Set channel numbers */ + input_terminal_desc.bNrChannels = u_audio_get_playback_channels(card); + as_type_i_desc.bNrChannels = u_audio_get_playback_channels(card); + + /* Set sample rates */ + rate = u_audio_get_playback_rate(card); + sam_freq = as_type_i_desc.tSamFreq[0]; + memcpy(sam_freq, &rate, 3); + + /* Todo: Set Sample bits and other parameters */ + + return; +} + +/* audio function driver setup/binding */ +static int __init +f_audio_bind(struct usb_configuration *c, struct usb_function *f) +{ + struct usb_composite_dev *cdev = c->cdev; + struct f_audio *audio = func_to_audio(f); + int status; + struct usb_ep *ep; + + f_audio_build_desc(audio); + + /* allocate instance-specific interface IDs, and patch descriptors */ + 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; + as_interface_alt_0_desc.bInterfaceNumber = status; + as_interface_alt_1_desc.bInterfaceNumber = status; + + status = -ENODEV; + + /* allocate instance-specific endpoints */ + ep = usb_ep_autoconfig(cdev->gadget, &as_out_ep_desc); + if (!ep) + goto fail; + audio->out_ep = ep; + audio->out_ep->desc = &as_out_ep_desc; + ep->driver_data = cdev; /* claim */ + + status = -ENOMEM; + + /* copy descriptors, and track endpoint copies */ + f->descriptors = usb_copy_descriptors(f_audio_desc); + + /* + * support all relevant hardware speeds... we expect that when + * hardware is dual speed, all bulk-capable endpoints work at + * both speeds + */ + if (gadget_is_dualspeed(c->cdev->gadget)) { + c->highspeed = true; + f->hs_descriptors = usb_copy_descriptors(f_audio_desc); + } + + return 0; + +fail: + + return status; +} + +static void +f_audio_unbind(struct usb_configuration *c, struct usb_function *f) +{ + struct f_audio *audio = func_to_audio(f); + + usb_free_descriptors(f->descriptors); + usb_free_descriptors(f->hs_descriptors); + kfree(audio); +} + +/*-------------------------------------------------------------------------*/ + +static int generic_set_cmd(struct usb_audio_control *con, u8 cmd, int value) +{ + con->data[cmd] = value; + + return 0; +} + +static int generic_get_cmd(struct usb_audio_control *con, u8 cmd) +{ + return con->data[cmd]; +} + +/* Todo: add more control selecotor dynamically */ +int __init control_selector_init(struct f_audio *audio) +{ + INIT_LIST_HEAD(&audio->cs); + list_add(&feature_unit.list, &audio->cs); + + INIT_LIST_HEAD(&feature_unit.control); + list_add(&mute_control.list, &feature_unit.control); + list_add(&volume_control.list, &feature_unit.control); + + volume_control.data[UAC__CUR] = 0xffc0; + volume_control.data[UAC__MIN] = 0xe3a0; + volume_control.data[UAC__MAX] = 0xfff0; + volume_control.data[UAC__RES] = 0x0030; + + return 0; +} + +/** + * audio_bind_config - add USB audio function to a configuration + * @c: the configuration to supcard the USB audio function + * Context: single threaded during gadget setup + * + * Returns zero on success, else negative errno. + */ +int __init audio_bind_config(struct usb_configuration *c) +{ + struct f_audio *audio; + int status; + + /* allocate and initialize one new instance */ + audio = kzalloc(sizeof *audio, GFP_KERNEL); + if (!audio) + return -ENOMEM; + + audio->card.func.name = "g_audio"; + audio->card.gadget = c->cdev->gadget; + + INIT_LIST_HEAD(&audio->play_queue); + spin_lock_init(&audio->lock); + + /* set up ASLA audio devices */ + status = gaudio_setup(&audio->card); + if (status < 0) + goto setup_fail; + + audio->card.func.strings = audio_strings; + audio->card.func.bind = f_audio_bind; + audio->card.func.unbind = f_audio_unbind; + audio->card.func.set_alt = f_audio_set_alt; + audio->card.func.setup = f_audio_setup; + audio->card.func.disable = f_audio_disable; + + control_selector_init(audio); + + INIT_WORK(&audio->playback_work, f_audio_playback_work); + + status = usb_add_function(c, &audio->card.func); + if (status) + goto add_fail; + + INFO(c->cdev, "audio_buf_size %d, req_buf_size %d, req_count %d\n", + audio_buf_size, req_buf_size, req_count); + + return status; + +add_fail: + gaudio_cleanup(); +setup_fail: + kfree(audio); + return status; +} |