From c6994e6f067cf0fc4c6cca3d164018b1150916f8 Mon Sep 17 00:00:00 2001 From: Bryan Wu Date: Wed, 3 Jun 2009 09:17:58 -0400 Subject: USB: gadget: add USB Audio Gadget driver Funtions added: - setup all the USB audio class device descriptors - handle class specific setup request - receive data from USB host by ISO transfer - play audio data by ALSA sound card - open and setup playback PCM interface - set default playback PCM parameters - provide playback functions for USB audio driver - provide PCM parameters set/get functions Test on: - Host: Ubuntu 8.10, kernel 2.6.27 - Gadget: EZKIT-BF548 with ASoC AD1980 codec Todo: - add real Mute control code - add real Volume control code - maybe find another way to replace dynamic buffer handling with static buffer allocation - test on Windows system - provide control interface to handle mute/volume control - provide capture interface in the future - test on BF527, other USB device controler and other audio codec Signed-off-by: Bryan Wu Signed-off-by: Mike Frysinger Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/audio.c | 302 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 302 insertions(+) create mode 100644 drivers/usb/gadget/audio.c (limited to 'drivers/usb/gadget/audio.c') diff --git a/drivers/usb/gadget/audio.c b/drivers/usb/gadget/audio.c new file mode 100644 index 0000000..94de7e8 --- /dev/null +++ b/drivers/usb/gadget/audio.c @@ -0,0 +1,302 @@ +/* + * audio.c -- Audio gadget driver + * + * Copyright (C) 2008 Bryan Wu + * Copyright (C) 2008 Analog Devices, Inc + * + * Enter bugs at http://blackfin.uclinux.org/ + * + * Licensed under the GPL-2 or later. + */ + +/* #define VERBOSE_DEBUG */ + +#include +#include + +#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 NetChip Technologies for donating this product ID. */ +#define AUDIO_VENDOR_NUM 0x0525 /* NetChip */ +#define AUDIO_PRODUCT_NUM 0xa4a1 /* 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 "); +MODULE_LICENSE("GPL"); + -- cgit v1.1