/*
* audio.c -- Audio gadget 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.
*/
/* #define VERBOSE_DEBUG */
#include <linux/kernel.h>
#include <linux/utsname.h>
#include "u_audio.h"
#define DRIVER_DESC "Linux USB Audio Gadget"
#define DRIVER_VERSION "Dec 18, 2008"
/*-------------------------------------------------------------------------*/
/*
* Kbuild is not very cooperative with respect to linking separately
* compiled library objects into one module. So for now we won't use
* separate compilation ... ensuring init/exit sections work to shrink
* the runtime footprint, and giving us at least some parts of what
* a "gcc --combine ... part1.c part2.c part3.c ... " build would.
*/
#include "composite.c"
#include "usbstring.c"
#include "config.c"
#include "epautoconf.c"
#include "u_audio.c"
#include "f_audio.c"
/*-------------------------------------------------------------------------*/
/* DO NOT REUSE THESE IDs with a protocol-incompatible driver!! Ever!!
* Instead: allocate your own, using normal USB-IF procedures.
*/
/* Thanks to Linux Foundation for donating this product ID. */
#define AUDIO_VENDOR_NUM 0x1d6b /* Linux Foundation */
#define AUDIO_PRODUCT_NUM 0x0101 /* Linux-USB Audio Gadget */
/*-------------------------------------------------------------------------*/
static struct usb_device_descriptor device_desc = {
.bLength = sizeof device_desc,
.bDescriptorType = USB_DT_DEVICE,
.bcdUSB = __constant_cpu_to_le16(0x200),
.bDeviceClass = USB_CLASS_PER_INTERFACE,
.bDeviceSubClass = 0,
.bDeviceProtocol = 0,
/* .bMaxPacketSize0 = f(hardware) */
/* Vendor and product id defaults change according to what configs
* we support. (As does bNumConfigurations.) These values can
* also be overridden by module parameters.
*/
.idVendor = __constant_cpu_to_le16(AUDIO_VENDOR_NUM),
.idProduct = __constant_cpu_to_le16(AUDIO_PRODUCT_NUM),
/* .bcdDevice = f(hardware) */
/* .iManufacturer = DYNAMIC */
/* .iProduct = DYNAMIC */
/* NO SERIAL NUMBER */
.bNumConfigurations = 1,
};
static struct usb_otg_descriptor otg_descriptor = {
.bLength = sizeof otg_descriptor,
.bDescriptorType = USB_DT_OTG,
/* REVISIT SRP-only hardware is possible, although
* it would not be called "OTG" ...
*/
.bmAttributes = USB_OTG_SRP | USB_OTG_HNP,
};
static const struct usb_descriptor_header *otg_desc[] = {
(struct usb_descriptor_header *) &otg_descriptor,
NULL,
};
/*-------------------------------------------------------------------------*/
/**
* Handle USB audio endpoint set/get command in setup class request
*/
static int audio_set_endpoint_req(struct usb_configuration *c,
const struct usb_ctrlrequest *ctrl)
{
struct usb_composite_dev *cdev = c->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 SET_CUR:
value = 0;
break;
case SET_MIN:
break;
case SET_MAX:
break;
case SET_RES:
break;
case SET_MEM:
break;
default:
break;
}
return value;
}
static int audio_get_endpoint_req(struct usb_configuration *c,
const struct usb_ctrlrequest *ctrl)
{
struct usb_composite_dev *cdev = c->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 GET_CUR:
case GET_MIN:
case GET_MAX:
case GET_RES:
value = 3;
break;
case GET_MEM:
break;
default:
break;
}
return value;
}
static int
audio_setup(struct usb_configuration *c, const struct usb_ctrlrequest *ctrl)
{
struct usb_composite_dev *cdev = c->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 except
* Audio class messages; interface activation uses set_alt().
*/
switch (ctrl->bRequestType) {
case USB_AUDIO_SET_ENDPOINT:
value = audio_set_endpoint_req(c, ctrl);
break;
case USB_AUDIO_GET_ENDPOINT:
value = audio_get_endpoint_req(c, 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 __init audio_do_config(struct usb_configuration *c)
{
/* FIXME alloc iConfiguration string, set it in c->strings */
if (gadget_is_otg(c->cdev->gadget)) {
c->descriptors = otg_desc;
c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
}
audio_bind_config(c);
return 0;
}
static struct usb_configuration audio_config_driver = {
.label = DRIVER_DESC,
.bind = audio_do_config,
.setup = audio_setup,
.bConfigurationValue = 1,
/* .iConfiguration = DYNAMIC */
.bmAttributes = USB_CONFIG_ATT_SELFPOWER,
};
/*-------------------------------------------------------------------------*/
static int __init audio_bind(struct usb_composite_dev *cdev)
{
int gcnum;
int status;
gcnum = usb_gadget_controller_number(cdev->gadget);
if (gcnum >= 0)
device_desc.bcdDevice = cpu_to_le16(0x0300 | gcnum);
else {
ERROR(cdev, "controller '%s' not recognized; trying %s\n",
cdev->gadget->name,
audio_config_driver.label);
device_desc.bcdDevice =
__constant_cpu_to_le16(0x0300 | 0x0099);
}
/* device descriptor strings: manufacturer, product */
snprintf(manufacturer, sizeof manufacturer, "%s %s with %s",
init_utsname()->sysname, init_utsname()->release,
cdev->gadget->name);
status = usb_string_id(cdev);
if (status < 0)
goto fail;
strings_dev[STRING_MANUFACTURER_IDX].id = status;
device_desc.iManufacturer = status;
status = usb_string_id(cdev);
if (status < 0)
goto fail;
strings_dev[STRING_PRODUCT_IDX].id = status;
device_desc.iProduct = status;
status = usb_add_config(cdev, &audio_config_driver);
if (status < 0)
goto fail;
INFO(cdev, "%s, version: %s\n", DRIVER_DESC, DRIVER_VERSION);
return 0;
fail:
return status;
}
static int __exit audio_unbind(struct usb_composite_dev *cdev)
{
return 0;
}
static struct usb_composite_driver audio_driver = {
.name = "g_audio",
.dev = &device_desc,
.strings = audio_strings,
.bind = audio_bind,
.unbind = __exit_p(audio_unbind),
};
static int __init init(void)
{
return usb_composite_register(&audio_driver);
}
module_init(init);
static void __exit cleanup(void)
{
usb_composite_unregister(&audio_driver);
}
module_exit(cleanup);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_AUTHOR("Bryan Wu <cooloney@kernel.org>");
MODULE_LICENSE("GPL");
