/* * 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 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(0), .idProduct = __constant_cpu_to_le16(0), // .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 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_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 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 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_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_ENDPOINT: value = audio_set_endpoint_req(c, ctrl); break; case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_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");