ladybird/Kernel/Bus/USB/USBDescriptors.h

119 lines
3.5 KiB
C++

/*
* Copyright (c) 2021, Jesse Buhagiar <jooster669@gmail.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Types.h>
namespace Kernel::USB {
struct [[gnu::packed]] USBDescriptorCommon {
u8 length;
u8 descriptor_type;
};
//
// Device Descriptor
// =================
//
// This descriptor type (stored on the device), represents the device, and gives
// information related to it, such as the USB specification it complies to,
// as well as the vendor and product ID of the device.
//
// https://beyondlogic.org/usbnutshell/usb5.shtml#DeviceDescriptors
struct [[gnu::packed]] USBDeviceDescriptor {
USBDescriptorCommon descriptor_header;
u16 usb_spec_compliance_bcd;
u8 device_class;
u8 device_sub_class;
u8 device_protocol;
u8 max_packet_size;
u16 vendor_id;
u16 product_id;
u16 device_release_bcd;
u8 manufacturer_id_descriptor_index;
u8 product_string_descriptor_index;
u8 serial_number_descriptor_index;
u8 num_configurations;
};
static_assert(sizeof(USBDeviceDescriptor) == 18);
//
// Configuration Descriptor
// ========================
//
// A USB device can have multiple configurations, which tells us about how the
// device is physically configured (e.g how it's powered, max power consumption etc).
//
struct [[gnu::packed]] USBConfigurationDescriptor {
USBDescriptorCommon descriptor_header;
u16 total_length;
u8 number_of_interfaces;
u8 configuration_value;
u8 configuration_string_descriptor_index;
u8 attributes_bitmap;
u8 max_power_in_ma;
};
//
// Interface Descriptor
// ====================
//
// An interface descriptor describes to us one or more endpoints, grouped
// together to define a singular function of a device.
// As an example, a USB webcam might have two interface descriptors; one
// for the camera, and one for the microphone.
//
struct [[gnu::packed]] USBInterfaceDescriptor {
USBDescriptorCommon descriptor_header;
u8 interface_id;
u8 alternate_setting;
u8 number_of_endpoints;
u8 interface_class_code;
u8 interface_sub_class_code;
u8 interface_protocol;
u8 interface_string_descriptor_index;
};
//
// Endpoint Descriptor
// ===================
//
// The lowest leaf in the configuration tree. And endpoint descriptor describes
// the physical transfer properties of the endpoint (that isn't endpoint0).
// The description given by this structure is used by a pipe to create a
// "connection" from the host to the device.
// https://docs.microsoft.com/en-us/windows-hardware/drivers/usbcon/usb-endpoints-and-their-pipes
struct [[gnu::packed]] USBEndpointDescriptor {
USBDescriptorCommon descriptor_header;
u8 endpoint_address;
u8 endpoint_attributes_bitmap;
u16 max_packet_size;
u8 poll_interval_in_frames;
};
//
// USB 1.1/2.0 Hub Descriptor
// ==============
//
struct [[gnu::packed]] USBHubDescriptor {
USBDescriptorCommon descriptor_header;
u8 number_of_downstream_ports;
u16 hub_characteristics;
u8 power_on_to_power_good_time;
u8 hub_controller_current;
// NOTE: This does not contain DeviceRemovable or PortPwrCtrlMask because a struct cannot have two VLAs in a row.
};
static constexpr u8 DESCRIPTOR_TYPE_DEVICE = 0x01;
static constexpr u8 DESCRIPTOR_TYPE_CONFIGURATION = 0x02;
static constexpr u8 DESCRIPTOR_TYPE_STRING = 0x03;
static constexpr u8 DESCRIPTOR_TYPE_INTERFACE = 0x04;
static constexpr u8 DESCRIPTOR_TYPE_ENDPOINT = 0x05;
static constexpr u8 DESCRIPTOR_TYPE_DEVICE_QUALIFIER = 0x06;
static constexpr u8 DESCRIPTOR_TYPE_HUB = 0x29;
}