linux/drivers/usb/gadget/f_audio.c
Takashi Iwai f07ff97b01 usb/gadget: Replace the old USB audio FU definitions in f_audio.c
The USB audio FU definitions were renewed by the commit
    65f25da44b
    ALSA: usb-audio: unify constants from specification

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2010-06-01 07:42:03 +02:00

801 lines
20 KiB
C

/*
* 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 <asm/atomic.h>
#include "u_audio.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 uac_ac_header_descriptor_v1_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 uac_output_terminal_descriptor_v1 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 uac_as_header_descriptor_v1 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 __initdata = {
.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,
};
/* string IDs are assigned dynamically */
#define STRING_MANUFACTURER_IDX 0
#define STRING_PRODUCT_IDX 1
static char manufacturer[50];
static struct usb_string strings_dev[] = {
[STRING_MANUFACTURER_IDX].s = manufacturer,
[STRING_PRODUCT_IDX].s = DRIVER_DESC,
{ } /* end of list */
};
static struct usb_gadget_strings stringtab_dev = {
.language = 0x0409, /* en-us */
.strings = strings_dev,
};
static struct usb_gadget_strings *audio_strings[] = {
&stringtab_dev,
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;
struct usb_endpoint_descriptor *out_desc;
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);
return;
}
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(&copy_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 = 0;
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 = 3;
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, audio->out_desc);
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(&copy_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;
ep->driver_data = cdev; /* claim */
status = -ENOMEM;
/* supcard 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;
f->hs_descriptors = usb_copy_descriptors(f_audio_desc);
} else
f->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);
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 fucntion 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;
audio->out_desc = &as_out_ep_desc;
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;
}