forked from KolibriOS/kolibrios
927 lines
39 KiB
PHP
927 lines
39 KiB
PHP
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; Implementation of the USB protocol for device enumeration.
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; Manage a USB device when it becomes ready for USB commands:
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; configure, enumerate, load the corresponding driver(s),
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; pass device information to the driver.
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; =============================================================================
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; ================================= Constants =================================
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; =============================================================================
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; USB standard request codes
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USB_GET_STATUS = 0
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USB_CLEAR_FEATURE = 1
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USB_SET_FEATURE = 3
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USB_SET_ADDRESS = 5
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USB_GET_DESCRIPTOR = 6
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USB_SET_DESCRIPTOR = 7
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USB_GET_CONFIGURATION = 8
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USB_SET_CONFIGURATION = 9
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USB_GET_INTERFACE = 10
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USB_SET_INTERFACE = 11
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USB_SYNCH_FRAME = 12
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; USB standard descriptor types
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USB_DEVICE_DESCR = 1
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USB_CONFIG_DESCR = 2
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USB_STRING_DESCR = 3
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USB_INTERFACE_DESCR = 4
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USB_ENDPOINT_DESCR = 5
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USB_DEVICE_QUALIFIER_DESCR = 6
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USB_OTHER_SPEED_CONFIG_DESCR = 7
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USB_INTERFACE_POWER_DESCR = 8
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; Possible speeds of USB devices
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USB_SPEED_FS = 0 ; full-speed
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USB_SPEED_LS = 1 ; low-speed
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USB_SPEED_HS = 2 ; high-speed
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; Compile-time setting. If set, the code will dump all descriptors as they are
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; read to the debug board.
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USB_DUMP_DESCRIPTORS = 1
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; =============================================================================
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; ================================ Structures =================================
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; =============================================================================
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; USB descriptors. See USB specification for detailed explanations.
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; First two bytes of every descriptor have the same meaning.
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struct usb_descr
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bLength db ?
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; Size of this descriptor in bytes
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bDescriptorType db ?
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; One of USB_*_DESCR constants.
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ends
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; USB device descriptor
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struct usb_device_descr usb_descr
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bcdUSB dw ?
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; USB Specification Release number in BCD, e.g. 110h = USB 1.1
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bDeviceClass db ?
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; USB Device Class Code
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bDeviceSubClass db ?
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; USB Device Subclass Code
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bDeviceProtocol db ?
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; USB Device Protocol Code
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bMaxPacketSize0 db ?
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; Maximum packet size for zero endpoint
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idVendor dw ?
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; Vendor ID
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idProduct dw ?
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; Product ID
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bcdDevice dw ?
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; Device release number in BCD
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iManufacturer db ?
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; Index of string descriptor describing manufacturer
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iProduct db ?
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; Index of string descriptor describing product
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iSerialNumber db ?
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; Index of string descriptor describing serial number
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bNumConfigurations db ?
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; Number of possible configurations
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ends
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; USB configuration descriptor
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struct usb_config_descr usb_descr
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wTotalLength dw ?
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; Total length of data returned for this configuration
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bNumInterfaces db ?
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; Number of interfaces in this configuration
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bConfigurationValue db ?
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; Value for SET_CONFIGURATION control request
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iConfiguration db ?
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; Index of string descriptor describing this configuration
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bmAttributes db ?
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; Bit 6 is SelfPowered, bit 5 is RemoteWakeupSupported,
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; bit 7 must be 1, other bits must be 0
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bMaxPower db ?
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; Maximum power consumption from the bus in 2mA units
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ends
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; USB interface descriptor
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struct usb_interface_descr usb_descr
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; The following two fields work in pair. Sometimes one interface can work
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; in different modes; e.g. videostream from web-cameras requires different
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; bandwidth depending on resolution/quality/compression settings.
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; Each mode of each interface has its own descriptor with its own endpoints
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; following; all descriptors for one interface have the same bInterfaceNumber,
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; and different bAlternateSetting.
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; By default, any interface operates in mode with bAlternateSetting = 0.
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; Often this is the only mode. If there are another modes, the active mode
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; is selected by SET_INTERFACE(bAlternateSetting) control request.
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bInterfaceNumber db ?
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bAlternateSetting db ?
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bNumEndpoints db ?
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; Number of endpoints used by this interface, excluding zero endpoint
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bInterfaceClass db ?
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; USB Interface Class Code
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bInterfaceSubClass db ?
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; USB Interface Subclass Code
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bInterfaceProtocol db ?
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; USB Interface Protocol Code
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iInterface db ?
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; Index of string descriptor describing this interface
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ends
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; USB endpoint descriptor
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struct usb_endpoint_descr usb_descr
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bEndpointAddress db ?
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; Lower 4 bits form endpoint number,
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; upper bit is 0 for OUT endpoints and 1 for IN endpoints,
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; other bits must be zero
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bmAttributes db ?
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; Lower 2 bits form transfer type, one of *_PIPE,
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; other bits must be zero for non-isochronous endpoints;
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; refer to the USB specification for meaning in isochronous case
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wMaxPacketSize dw ?
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; Lower 11 bits form maximum packet size,
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; next two bits specify the number of additional transactions per microframe
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; for high-speed periodic endpoints, other bits must be zero.
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bInterval db ?
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; Interval for polling endpoint for data transfers.
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; Isochronous and high-speed interrupt endpoints: poll every 2^(bInterval-1)
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; (micro)frames
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; Full/low-speed interrupt endpoints: poll every bInterval frames
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; High-speed bulk/control OUT endpoints: maximum NAK rate
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ends
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; =============================================================================
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; =================================== Code ====================================
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; =============================================================================
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; When a new device is ready to be configured, a controller-specific code
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; calls usb_new_device.
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; The sequence of further actions:
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; * open pipe for the zero endpoint (usb_new_device);
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; maximum packet size is not known yet, but it must be at least 8 bytes,
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; so it is safe to send packets with <= 8 bytes
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; * issue SET_ADDRESS control request (usb_new_device)
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; * set the new device address in the pipe (usb_set_address_callback)
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; * notify a controller-specific code that initialization of other ports
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; can be started (usb_set_address_callback)
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; * issue GET_DESCRIPTOR control request for first 8 bytes of device descriptor
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; (usb_after_set_address)
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; * first 8 bytes of device descriptor contain the true packet size for zero
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; endpoint, so set the true packet size (usb_get_descr8_callback)
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; * first 8 bytes of a descriptor contain the full size of this descriptor,
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; issue GET_DESCRIPTOR control request for the full device descriptor
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; (usb_after_set_endpoint_size)
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; * issue GET_DESCRIPTOR control request for first 8 bytes of configuration
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; descriptor (usb_get_descr_callback)
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; * issue GET_DESCRIPTOR control request for full configuration descriptor
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; (usb_know_length_callback)
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; * issue SET_CONFIGURATION control request (usb_set_config_callback)
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; * parse configuration descriptor, load the corresponding driver(s),
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; pass the configuration descriptor to the driver and let the driver do
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; the further work (usb_got_config_callback)
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; This function is called from controller-specific part
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; when a new device is ready to be configured.
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; in: ecx -> pseudo-pipe, part of usb_pipe
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; in: esi -> usb_controller
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; in: [esi+usb_controller.ResettingHub] is the pointer to usb_hub for device,
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; NULL if the device is connected to the root hub
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; in: [esi+usb_controller.ResettingPort] is the port for the device, zero-based
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; in: [esi+usb_controller.ResettingSpeed] is the speed of the device, one of
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; USB_SPEED_xx.
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; out: eax = 0 <=> failed, the caller should disable the port.
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proc usb_new_device
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push ebx edi ; save used registers to be stdcall
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; 1. Allocate resources. Any device uses the following resources:
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; - device address in the bus
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; - memory for device data
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; - pipe for zero endpoint
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; If some allocation fails, we must undo our actions. Closing the pipe
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; is a hard task, so we avoid it and open the pipe as the last resource.
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; The order for other two allocations is quite arbitrary.
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; 1a. Allocate a bus address.
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push ecx
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call usb_set_address_request
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pop ecx
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; 1b. If failed, just return zero.
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test eax, eax
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jz .nothing
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; 1c. Allocate memory for device data.
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; For now, we need sizeof.usb_device_data and extra 8 bytes for GET_DESCRIPTOR
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; input and output, see usb_after_set_address. Later we will reallocate it
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; to actual size needed for descriptors.
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push sizeof.usb_device_data + 8
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pop eax
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push ecx
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call malloc
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pop ecx
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; 1d. If failed, free the bus address and return zero.
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test eax, eax
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jz .nomemory
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; 1e. Open pipe for endpoint zero.
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; For now, we do not know the actual maximum packet size;
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; for full-speed devices it can be any of 8, 16, 32, 64 bytes,
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; low-speed devices must have 8 bytes, high-speed devices must have 64 bytes.
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; Thus, we must use some fake "maximum packet size" until the actual size
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; will be known. However, the maximum packet size must be at least 8, and
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; initial stages of the configuration process involves only packets of <= 8
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; bytes, they will be transferred correctly as long as
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; the fake "maximum packet size" is also at least 8.
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; Thus, any number >= 8 is suitable for actual hardware.
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; However, software emulation of EHCI in VirtualBox assumes that high-speed
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; control transfers are those originating from pipes with max packet size = 64,
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; even on early stages of the configuration process. This is incorrect,
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; but we have no specific preferences, so let VirtualBox be happy and use 64
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; as the fake "maximum packet size".
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push eax
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; We will need many zeroes.
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; "push edi" is one byte, "push 0" is two bytes; save space, use edi.
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xor edi, edi
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stdcall usb_open_pipe, ecx, edi, 64, edi, edi
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; Put pointer to pipe into ebx. "xchg eax,reg" is one byte, mov is two bytes.
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xchg eax, ebx
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pop eax
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; 1f. If failed, free the memory, the bus address and return zero.
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test ebx, ebx
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jz .freememory
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; 2. Store pointer to device data in the pipe structure.
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mov [ebx+usb_pipe.DeviceData], eax
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; 3. Init device data, using usb_controller.Resetting* variables.
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mov [eax+usb_device_data.NumPipes], 1
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mov [eax+usb_device_data.ConfigDataSize], edi
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mov [eax+usb_device_data.Interfaces], edi
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movzx ecx, [esi+usb_controller.ResettingPort]
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; Note: the following write zeroes
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; usb_device_data.DeviceDescrSize, usb_device_data.NumInterfaces,
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; usb_device_data.Speed.
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mov dword [eax+usb_device_data.Port], ecx
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mov dl, [esi+usb_controller.ResettingSpeed]
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mov [eax+usb_device_data.Speed], dl
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mov edx, [esi+usb_controller.ResettingHub]
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mov [eax+usb_device_data.Hub], edx
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; 4. Store pointer to the config pipe in the hub data.
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; Config pipe serves as device identifier.
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; Root hubs use the array inside usb_controller structure,
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; non-root hubs use the array immediately after usb_hub structure.
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test edx, edx
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jz .roothub
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mov edx, [edx+usb_hub.ConnectedDevicesPtr]
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mov [edx+ecx*4], ebx
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jmp @f
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.roothub:
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mov [esi+usb_controller.DevicesByPort+ecx*4], ebx
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@@:
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call usb_reinit_pipe_list
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; 5. Issue SET_ADDRESS control request, using buffer filled in step 1a.
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; Use the return value from usb_control_async as our return value;
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; if it is zero, then something has failed.
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lea eax, [esi+usb_controller.SetAddressBuffer]
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stdcall usb_control_async, ebx, eax, edi, edi, usb_set_address_callback, edi, edi
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.nothing:
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; 6. Return.
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pop edi ebx ; restore used registers to be stdcall
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ret
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; Handlers of failures in steps 1b, 1d, 1f.
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.freememory:
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call free
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jmp .freeaddr
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.nomemory:
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dbgstr 'No memory for device data'
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.freeaddr:
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mov ecx, dword [esi+usb_controller.SetAddressBuffer+2]
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bts [esi+usb_controller.ExistingAddresses], ecx
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xor eax, eax
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jmp .nothing
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endp
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; Helper procedure for usb_new_device.
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; Allocates a new USB address and fills usb_controller.SetAddressBuffer
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; with data for SET_ADDRESS(allocated_address) request.
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; out: eax = 0 <=> failed
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; Destroys edi.
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proc usb_set_address_request
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; There are 128 bits, one for each possible address.
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; Note: only the USB thread works with usb_controller.ExistingAddresses,
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; so there is no need for synchronization.
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; We must find a bit set to 1 and clear it.
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; 1. Find the first dword which has a nonzero bit = which is nonzero.
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mov ecx, 128/32
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lea edi, [esi+usb_controller.ExistingAddresses]
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xor eax, eax
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repz scasd
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; 2. If all dwords are zero, return an error.
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jz .error
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; 3. The dword at [edi-4] is nonzero. Find the lowest nonzero bit.
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bsf eax, [edi-4]
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; Now eax = bit number inside the dword at [edi-4].
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; 4. Clear the bit.
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btr [edi-4], eax
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; 5. Generate the address by edi = memory address and eax = bit inside dword.
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; Address = eax + 8 * (edi-4 - (esi+usb_controller.ExistingAddress)).
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sub edi, esi
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lea edi, [eax+(edi-4-usb_controller.ExistingAddresses)*8]
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; 6. Store the allocated address in SetAddressBuffer and fill remaining fields.
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; Note that usb_controller is zeroed at allocation, so only command byte needs
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; to be filled.
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mov byte [esi+usb_controller.SetAddressBuffer+1], USB_SET_ADDRESS
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mov dword [esi+usb_controller.SetAddressBuffer+2], edi
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; 7. Return non-zero value in eax.
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inc eax
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.nothing:
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ret
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.error:
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dbgstr 'cannot allocate USB address'
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xor eax, eax
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jmp .nothing
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endp
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; This procedure is called by USB stack when SET_ADDRESS request initiated by
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; usb_new_device is completed, either successfully or unsuccessfully.
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; Note that USB stack uses esi = pointer to usb_controller.
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proc usb_set_address_callback stdcall, pipe:dword, status:dword, buffer:dword, length:dword, calldata:dword
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push ebx ; save ebx to be stdcall
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; Load data to registers for further references.
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mov ebx, [pipe]
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mov ecx, dword [esi+usb_controller.SetAddressBuffer+2]
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mov eax, [esi+usb_controller.HardwareFunc]
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; 1. Check whether the device has accepted new address. If so, proceed to 2.
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; Otherwise, go to 3.
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cmp [status], 0
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jnz .error
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; 2. Address accepted.
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; 2a. The controller-specific structure for the control pipe still uses
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; zero address. Call the controller-specific function to change it to
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; the actual address.
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; Note that the hardware could cache the controller-specific structure,
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; so setting the address could take some time until the cache is evicted.
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; Thus, the call is asynchronous; meet us in usb_after_set_address when it will
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; be safe to continue.
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dbgstr 'address set in device'
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call [eax+usb_hardware_func.SetDeviceAddress]
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; 2b. If the port is in non-root hub, clear 'reset in progress' flag.
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; In any case, proceed to 4.
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mov eax, [esi+usb_controller.ResettingHub]
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test eax, eax
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jz .return
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and [eax+usb_hub.Actions], not HUB_RESET_IN_PROGRESS
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.return:
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; 4. Address configuration done, we can proceed with other ports.
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; Call the worker function for that.
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call usb_test_pending_port
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.nothing:
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pop ebx ; restore ebx to be stdcall
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ret
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.error:
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; 3. Device error: device not responding, disconnect etc.
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DEBUGF 1,'K : error %d in SET_ADDRESS, USB device disabled\n',[status]
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; 3a. The address has not been accepted. Mark it as free.
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bts dword [esi+usb_controller.ExistingAddresses], ecx
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; 3b. Disable the port with bad device.
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; For the root hub, call the controller-specific function and go to 6.
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; For non-root hubs, let the hub code do its work and return (the request
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; could take some time, the hub code is responsible for proceeding).
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cmp [esi+usb_controller.ResettingHub], 0
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jz .roothub
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mov eax, [esi+usb_controller.ResettingHub]
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call usb_hub_disable_resetting_port
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jmp .nothing
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.roothub:
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movzx ecx, [esi+usb_controller.ResettingPort]
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call [eax+usb_hardware_func.PortDisable]
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jmp .return
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endp
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||
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|
||
|
; This procedure is called from usb_subscription_done when the hardware cache
|
||
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; is cleared after request from usb_set_address_callback.
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||
|
; in: ebx -> usb_pipe
|
||
|
proc usb_after_set_address
|
||
|
dbgstr 'address set for controller'
|
||
|
; Issue control transfer GET_DESCRIPTOR(DEVICE_DESCR) for first 8 bytes.
|
||
|
; Remember, we still do not know the actual packet size;
|
||
|
; 8-bytes-request is safe.
|
||
|
; usb_new_device has allocated 8 extra bytes besides sizeof.usb_device_data;
|
||
|
; use them for both input and output.
|
||
|
mov eax, [ebx+usb_pipe.DeviceData]
|
||
|
add eax, usb_device_data.DeviceDescriptor
|
||
|
mov dword [eax], \
|
||
|
80h + \ ; device-to-host, standard, device-wide
|
||
|
(USB_GET_DESCRIPTOR shl 8) + \ ; request
|
||
|
(0 shl 16) + \ ; descriptor index: there is only one
|
||
|
(USB_DEVICE_DESCR shl 24) ; descriptor type
|
||
|
mov dword [eax+4], 8 shl 16 ; data length
|
||
|
stdcall usb_control_async, ebx, eax, eax, 8, usb_get_descr8_callback, eax, 0
|
||
|
ret
|
||
|
endp
|
||
|
|
||
|
; This procedure is called by USB stack when GET_DESCRIPTOR(DEVICE_DESCR)
|
||
|
; request initiated by usb_after_set_address is completed, either successfully
|
||
|
; or unsuccessfully.
|
||
|
; Note that USB stack uses esi = pointer to usb_controller.
|
||
|
proc usb_get_descr8_callback stdcall, pipe:dword, status:dword, buffer:dword, length:dword, calldata:dword
|
||
|
; mov eax, [buffer]
|
||
|
; DEBUGF 1,'K : descr8: l=%x; %x %x %x %x %x %x %x %x\n',[length],\
|
||
|
; [eax]:2,[eax+1]:2,[eax+2]:2,[eax+3]:2,[eax+4]:2,[eax+5]:2,[eax+6]:2,[eax+7]:2
|
||
|
push edi ebx ; save used registers to be stdcall
|
||
|
mov ebx, [pipe]
|
||
|
; 1. Check whether the operation was successful.
|
||
|
; If not, say something to the debug board and stop the initialization.
|
||
|
cmp [status], 0
|
||
|
jnz .error
|
||
|
; 2. Length of descriptor must be at least sizeof.usb_device_descr bytes.
|
||
|
; If not, say something to the debug board and stop the initialization.
|
||
|
mov eax, [ebx+usb_pipe.DeviceData]
|
||
|
cmp [eax+usb_device_data.DeviceDescriptor+usb_device_descr.bLength], sizeof.usb_device_descr
|
||
|
jb .error
|
||
|
; 3. Now first 8 bytes of device descriptor are known;
|
||
|
; set DeviceDescrSize accordingly.
|
||
|
mov [eax+usb_device_data.DeviceDescrSize], 8
|
||
|
; 4. The controller-specific structure for the control pipe still uses
|
||
|
; the fake "maximum packet size". Call the controller-specific function to
|
||
|
; change it to the actual packet size from the device.
|
||
|
; Note that the hardware could cache the controller-specific structure,
|
||
|
; so changing it could take some time until the cache is evicted.
|
||
|
; Thus, the call is asynchronous; meet us in usb_after_set_endpoint_size
|
||
|
; when it will be safe to continue.
|
||
|
movzx ecx, [eax+usb_device_data.DeviceDescriptor+usb_device_descr.bMaxPacketSize0]
|
||
|
mov eax, [esi+usb_controller.HardwareFunc]
|
||
|
call [eax+usb_hardware_func.SetEndpointPacketSize]
|
||
|
.nothing:
|
||
|
; 5. Return.
|
||
|
pop ebx edi ; restore used registers to be stdcall
|
||
|
ret
|
||
|
.error:
|
||
|
dbgstr 'error with USB device descriptor'
|
||
|
jmp .nothing
|
||
|
endp
|
||
|
|
||
|
; This procedure is called from usb_subscription_done when the hardware cache
|
||
|
; is cleared after request from usb_get_descr8_callback.
|
||
|
; in: ebx -> usb_pipe
|
||
|
proc usb_after_set_endpoint_size
|
||
|
; 1. Reallocate memory for device data:
|
||
|
; add memory for now-known size of device descriptor and extra 8 bytes
|
||
|
; for further actions.
|
||
|
; 1a. Allocate new memory.
|
||
|
mov eax, [ebx+usb_pipe.DeviceData]
|
||
|
movzx eax, [eax+usb_device_data.DeviceDescriptor+usb_device_descr.bLength]
|
||
|
; save length for step 2
|
||
|
push eax
|
||
|
add eax, sizeof.usb_device_data + 8
|
||
|
; Note that malloc destroys ebx.
|
||
|
push ebx
|
||
|
call malloc
|
||
|
pop ebx
|
||
|
; 1b. If failed, say something to the debug board and stop the initialization.
|
||
|
test eax, eax
|
||
|
jz .nomemory
|
||
|
; 1c. Copy data from old memory to new memory and switch the pointer in usb_pipe.
|
||
|
push eax
|
||
|
push esi edi
|
||
|
mov esi, [ebx+usb_pipe.DeviceData]
|
||
|
mov [ebx+usb_pipe.DeviceData], eax
|
||
|
mov edi, eax
|
||
|
mov eax, esi
|
||
|
repeat sizeof.usb_device_data / 4
|
||
|
movsd
|
||
|
end repeat
|
||
|
pop edi esi
|
||
|
call usb_reinit_pipe_list
|
||
|
; 1d. Free the old memory.
|
||
|
; Note that free destroys ebx.
|
||
|
push ebx
|
||
|
call free
|
||
|
pop ebx
|
||
|
pop eax
|
||
|
; 2. Issue control transfer GET_DESCRIPTOR(DEVICE) for full descriptor.
|
||
|
; restore length saved in step 1a
|
||
|
pop edx
|
||
|
add eax, sizeof.usb_device_data
|
||
|
mov dword [eax], \
|
||
|
80h + \ ; device-to-host, standard, device-wide
|
||
|
(USB_GET_DESCRIPTOR shl 8) + \ ; request
|
||
|
(0 shl 16) + \ ; descriptor index: there is only one
|
||
|
(USB_DEVICE_DESCR shl 24) ; descriptor type
|
||
|
and dword [eax+4], 0
|
||
|
mov [eax+6], dl ; data length
|
||
|
stdcall usb_control_async, ebx, eax, eax, edx, usb_get_descr_callback, eax, 0
|
||
|
; 3. Return.
|
||
|
ret
|
||
|
.nomemory:
|
||
|
dbgstr 'No memory for device data'
|
||
|
ret
|
||
|
endp
|
||
|
|
||
|
; This procedure is called by USB stack when GET_DESCRIPTOR(DEVICE)
|
||
|
; request initiated by usb_after_set_endpoint_size is completed,
|
||
|
; either successfully or unsuccessfully.
|
||
|
proc usb_get_descr_callback stdcall, pipe:dword, status:dword, buffer:dword, length:dword, calldata:dword
|
||
|
; Note: the prolog is the same as in usb_get_descr8_callback.
|
||
|
push edi ebx ; save used registers to be stdcall
|
||
|
; 1. Check whether the operation was successful.
|
||
|
; If not, say something to the debug board and stop the initialization.
|
||
|
cmp [status], 0
|
||
|
jnz usb_get_descr8_callback.error
|
||
|
; The full descriptor is known, dump it if specified by compile-time option.
|
||
|
if USB_DUMP_DESCRIPTORS
|
||
|
mov eax, [buffer]
|
||
|
mov ecx, [length]
|
||
|
sub ecx, 8
|
||
|
jbe .skipdebug
|
||
|
DEBUGF 1,'K : device descriptor:'
|
||
|
@@:
|
||
|
DEBUGF 1,' %x',[eax]:2
|
||
|
inc eax
|
||
|
dec ecx
|
||
|
jnz @b
|
||
|
DEBUGF 1,'\n'
|
||
|
.skipdebug:
|
||
|
end if
|
||
|
; 2. Check that bLength is the same as was in the previous request.
|
||
|
; If not, say something to the debug board and stop the initialization.
|
||
|
; It is important, because usb_after_set_endpoint_size has allocated memory
|
||
|
; according to the old bLength. Note that [length] for control transfers
|
||
|
; includes 8 bytes of setup packet, so data length = [length] - 8.
|
||
|
mov eax, [buffer]
|
||
|
movzx ecx, [eax+usb_device_descr.bLength]
|
||
|
add ecx, 8
|
||
|
cmp [length], ecx
|
||
|
jnz usb_get_descr8_callback.error
|
||
|
; Amuse the user if she is watching the debug board.
|
||
|
mov cl, [eax+usb_device_descr.bNumConfigurations]
|
||
|
DEBUGF 1,'K : found USB device with ID %x:%x, %d configuration(s)\n',\
|
||
|
[eax+usb_device_descr.idVendor]:4,\
|
||
|
[eax+usb_device_descr.idProduct]:4,\
|
||
|
cl
|
||
|
; 3. If there are no configurations, stop the initialization.
|
||
|
cmp [eax+usb_device_descr.bNumConfigurations], 0
|
||
|
jz .nothing
|
||
|
; 4. Copy length of device descriptor to device data structure.
|
||
|
movzx edx, [eax+usb_device_descr.bLength]
|
||
|
mov [eax+usb_device_data.DeviceDescrSize-usb_device_data.DeviceDescriptor], dl
|
||
|
; 5. Issue control transfer GET_DESCRIPTOR(CONFIGURATION). We do not know
|
||
|
; the full length of that descriptor, so start with first 8 bytes, they contain
|
||
|
; the full length.
|
||
|
; usb_after_set_endpoint_size has allocated 8 extra bytes after the
|
||
|
; device descriptor, use them for both input and output.
|
||
|
add eax, edx
|
||
|
mov dword [eax], \
|
||
|
80h + \ ; device-to-host, standard, device-wide
|
||
|
(USB_GET_DESCRIPTOR shl 8) + \ ; request
|
||
|
(0 shl 16) + \ ; descriptor index: there is only one
|
||
|
(USB_CONFIG_DESCR shl 24) ; descriptor type
|
||
|
mov dword [eax+4], 8 shl 16 ; data length
|
||
|
stdcall usb_control_async, [pipe], eax, eax, 8, usb_know_length_callback, eax, 0
|
||
|
.nothing:
|
||
|
; 6. Return.
|
||
|
pop ebx edi ; restore used registers to be stdcall
|
||
|
ret
|
||
|
endp
|
||
|
|
||
|
; This procedure is called by USB stack when GET_DESCRIPTOR(CONFIGURATION)
|
||
|
; request initiated by usb_get_descr_callback is completed,
|
||
|
; either successfully or unsuccessfully.
|
||
|
proc usb_know_length_callback stdcall, pipe:dword, status:dword, buffer:dword, length:dword, calldata:dword
|
||
|
push ebx ; save used registers to be stdcall
|
||
|
; 1. Check whether the operation was successful.
|
||
|
; If not, say something to the debug board and stop the initialization.
|
||
|
cmp [status], 0
|
||
|
jnz .error
|
||
|
; 2. Get the total length of data associated with config descriptor and store
|
||
|
; it in device data structure. The total length must be at least
|
||
|
; sizeof.usb_config_descr bytes; if not, say something to the debug board and
|
||
|
; stop the initialization.
|
||
|
mov eax, [buffer]
|
||
|
mov edx, [pipe]
|
||
|
movzx ecx, [eax+usb_config_descr.wTotalLength]
|
||
|
mov eax, [edx+usb_pipe.DeviceData]
|
||
|
cmp ecx, sizeof.usb_config_descr
|
||
|
jb .error
|
||
|
mov [eax+usb_device_data.ConfigDataSize], ecx
|
||
|
; 3. Reallocate memory for device data:
|
||
|
; include usb_device_data structure, device descriptor,
|
||
|
; config descriptor with all associated data, and extra bytes
|
||
|
; sufficient for 8 bytes control packet and for one usb_interface_data struc.
|
||
|
; Align extra bytes to dword boundary.
|
||
|
if sizeof.usb_interface_data > 8
|
||
|
.extra_size = sizeof.usb_interface_data
|
||
|
else
|
||
|
.extra_size = 8
|
||
|
end if
|
||
|
; 3a. Allocate new memory.
|
||
|
movzx edx, [eax+usb_device_data.DeviceDescrSize]
|
||
|
lea eax, [ecx+edx+sizeof.usb_device_data+.extra_size+3]
|
||
|
and eax, not 3
|
||
|
push eax
|
||
|
call malloc
|
||
|
pop edx
|
||
|
; 3b. If failed, say something to the debug board and stop the initialization.
|
||
|
test eax, eax
|
||
|
jz .nomemory
|
||
|
; 3c. Copy data from old memory to new memory and switch the pointer in usb_pipe.
|
||
|
push eax
|
||
|
mov ebx, [pipe]
|
||
|
push esi edi
|
||
|
mov esi, [ebx+usb_pipe.DeviceData]
|
||
|
mov edi, eax
|
||
|
mov [ebx+usb_pipe.DeviceData], eax
|
||
|
mov eax, esi
|
||
|
movzx ecx, [esi+usb_device_data.DeviceDescrSize]
|
||
|
sub edx, .extra_size
|
||
|
mov [esi+usb_device_data.Interfaces], edx
|
||
|
add ecx, sizeof.usb_device_data + 8
|
||
|
mov edx, ecx
|
||
|
shr ecx, 2
|
||
|
and edx, 3
|
||
|
rep movsd
|
||
|
mov ecx, edx
|
||
|
rep movsb
|
||
|
pop edi esi
|
||
|
call usb_reinit_pipe_list
|
||
|
; 3d. Free old memory.
|
||
|
call free
|
||
|
pop eax
|
||
|
; 4. Issue control transfer GET_DESCRIPTOR(DEVICE) for full descriptor.
|
||
|
movzx ecx, [eax+usb_device_data.DeviceDescrSize]
|
||
|
mov edx, [eax+usb_device_data.ConfigDataSize]
|
||
|
lea eax, [eax+ecx+sizeof.usb_device_data]
|
||
|
mov dword [eax], \
|
||
|
80h + \ ; device-to-host, standard, device-wide
|
||
|
(USB_GET_DESCRIPTOR shl 8) + \ ; request
|
||
|
(0 shl 16) + \ ; descriptor index: there is only one
|
||
|
(USB_CONFIG_DESCR shl 24) ; descriptor type
|
||
|
and dword [eax+4], 0
|
||
|
mov word [eax+6], dx ; data length
|
||
|
stdcall usb_control_async, [pipe], eax, eax, edx, usb_set_config_callback, eax, 0
|
||
|
.nothing:
|
||
|
; 5. Return.
|
||
|
pop ebx ; restore used registers to be stdcall
|
||
|
ret
|
||
|
.error:
|
||
|
dbgstr 'error with USB configuration descriptor'
|
||
|
jmp .nothing
|
||
|
.nomemory:
|
||
|
dbgstr 'No memory for device data'
|
||
|
jmp .nothing
|
||
|
endp
|
||
|
|
||
|
; This procedure is called by USB stack when GET_DESCRIPTOR(CONFIGURATION)
|
||
|
; request initiated by usb_know_length_callback is completed,
|
||
|
; either successfully or unsuccessfully.
|
||
|
proc usb_set_config_callback stdcall, pipe:dword, status:dword, buffer:dword, length:dword, calldata:dword
|
||
|
; Note that the prolog is the same as in usb_know_length_callback.
|
||
|
push ebx ; save used registers to be stdcall
|
||
|
; 1. Check whether the operation was successful.
|
||
|
; If not, say something to the debug board and stop the initialization.
|
||
|
xor ecx, ecx
|
||
|
mov ebx, [pipe]
|
||
|
cmp [status], ecx
|
||
|
jnz usb_know_length_callback.error
|
||
|
; The full descriptor is known, dump it if specified by compile-time option.
|
||
|
if USB_DUMP_DESCRIPTORS
|
||
|
mov eax, [buffer]
|
||
|
mov ecx, [length]
|
||
|
sub ecx, 8
|
||
|
jbe .skip_debug
|
||
|
DEBUGF 1,'K : config descriptor:'
|
||
|
@@:
|
||
|
DEBUGF 1,' %x',[eax]:2
|
||
|
inc eax
|
||
|
dec ecx
|
||
|
jnz @b
|
||
|
DEBUGF 1,'\n'
|
||
|
.skip_debug:
|
||
|
xor ecx, ecx
|
||
|
end if
|
||
|
; 2. Issue control transfer SET_CONFIGURATION to activate this configuration.
|
||
|
; Usually this is the only configuration.
|
||
|
; Use extra bytes allocated by usb_know_length_callback;
|
||
|
; offset from device data start is stored in Interfaces.
|
||
|
mov eax, [ebx+usb_pipe.DeviceData]
|
||
|
mov edx, [buffer]
|
||
|
add eax, [eax+usb_device_data.Interfaces]
|
||
|
mov dl, [edx+usb_config_descr.bConfigurationValue]
|
||
|
mov dword [eax], USB_SET_CONFIGURATION shl 8
|
||
|
mov dword [eax+4], ecx
|
||
|
mov byte [eax+2], dl
|
||
|
stdcall usb_control_async, [pipe], eax, ecx, ecx, usb_got_config_callback, [buffer], ecx
|
||
|
pop ebx ; restore used registers to be stdcall
|
||
|
ret
|
||
|
endp
|
||
|
|
||
|
; This procedure is called by USB stack when SET_CONFIGURATION
|
||
|
; request initiated by usb_set_config_callback is completed,
|
||
|
; either successfully or unsuccessfully.
|
||
|
; If successfully, the device is configured and ready to work,
|
||
|
; pass the device to the corresponding driver(s).
|
||
|
proc usb_got_config_callback stdcall, pipe:dword, status:dword, buffer:dword, length:dword, calldata:dword
|
||
|
locals
|
||
|
InterfacesData dd ?
|
||
|
NumInterfaces dd ?
|
||
|
driver dd ?
|
||
|
endl
|
||
|
; 1. If there was an error, say something to the debug board and stop the
|
||
|
; initialization.
|
||
|
cmp [status], 0
|
||
|
jz @f
|
||
|
dbgstr 'USB error in SET_CONFIGURATION'
|
||
|
ret
|
||
|
@@:
|
||
|
push ebx edi ; save used registers to be stdcall
|
||
|
; 2. Sanity checks: the total length must be the same as before (because we
|
||
|
; have allocated memory assuming the old value), length of config descriptor
|
||
|
; must be at least sizeof.usb_config_descr (we use fields from it),
|
||
|
; there must be at least one interface.
|
||
|
mov ebx, [pipe]
|
||
|
mov ebx, [ebx+usb_pipe.DeviceData]
|
||
|
mov eax, [calldata]
|
||
|
mov edx, [ebx+usb_device_data.ConfigDataSize]
|
||
|
cmp [eax+usb_config_descr.wTotalLength], dx
|
||
|
jnz .invalid
|
||
|
cmp [eax+usb_config_descr.bLength], 9
|
||
|
jb .invalid
|
||
|
movzx edx, [eax+usb_config_descr.bNumInterfaces]
|
||
|
test edx, edx
|
||
|
jnz @f
|
||
|
.invalid:
|
||
|
dbgstr 'error: invalid configuration descriptor'
|
||
|
jmp .nothing
|
||
|
@@:
|
||
|
; 3. Store the number of interfaces in device data structure.
|
||
|
mov [ebx+usb_device_data.NumInterfaces], dl
|
||
|
; 4. If there is only one interface (which happens quite often),
|
||
|
; the memory allocated in usb_know_length_callback is sufficient.
|
||
|
; Otherwise (which also happens quite often), reallocate device data.
|
||
|
; 4a. Check whether there is only one interface. If so, skip this step.
|
||
|
cmp edx, 1
|
||
|
jz .has_memory
|
||
|
; 4b. Allocate new memory.
|
||
|
mov eax, [ebx+usb_device_data.Interfaces]
|
||
|
lea eax, [eax+edx*sizeof.usb_interface_data]
|
||
|
call malloc
|
||
|
; 4c. If failed, say something to the debug board and
|
||
|
; stop the initialization.
|
||
|
test eax, eax
|
||
|
jnz @f
|
||
|
dbgstr 'No memory for device data'
|
||
|
jmp .nothing
|
||
|
@@:
|
||
|
; 4d. Copy data from old memory to new memory and switch the pointer in usb_pipe.
|
||
|
push eax
|
||
|
push esi
|
||
|
mov ebx, [pipe]
|
||
|
mov edi, eax
|
||
|
mov esi, [ebx+usb_pipe.DeviceData]
|
||
|
mov [ebx+usb_pipe.DeviceData], eax
|
||
|
mov eax, esi
|
||
|
mov ecx, [esi+usb_device_data.Interfaces]
|
||
|
shr ecx, 2
|
||
|
rep movsd
|
||
|
pop esi
|
||
|
call usb_reinit_pipe_list
|
||
|
; 4e. Free old memory.
|
||
|
call free
|
||
|
pop ebx
|
||
|
.has_memory:
|
||
|
; 5. Initialize interfaces table: zero all contents.
|
||
|
mov edi, [ebx+usb_device_data.Interfaces]
|
||
|
add edi, ebx
|
||
|
mov [InterfacesData], edi
|
||
|
movzx ecx, [ebx+usb_device_data.NumInterfaces]
|
||
|
if sizeof.usb_interface_data <> 8
|
||
|
You have changed sizeof.usb_interface_data? Modify this place too.
|
||
|
end if
|
||
|
add ecx, ecx
|
||
|
xor eax, eax
|
||
|
rep stosd
|
||
|
; No interfaces are found yet.
|
||
|
mov [NumInterfaces], eax
|
||
|
; 6. Get the pointer to config descriptor data.
|
||
|
; Note: if there was reallocation, [buffer] is not valid anymore,
|
||
|
; so calculate value based on usb_device_data.
|
||
|
movzx eax, [ebx+usb_device_data.DeviceDescrSize]
|
||
|
lea eax, [eax+ebx+sizeof.usb_device_data]
|
||
|
mov [calldata], eax
|
||
|
mov ecx, [ebx+usb_device_data.ConfigDataSize]
|
||
|
; 7. Loop over all descriptors,
|
||
|
; scan for interface descriptors with bAlternateSetting = 0,
|
||
|
; load the corresponding driver, call its AddDevice function.
|
||
|
.descriptor_loop:
|
||
|
; While in loop: eax points to the current descriptor,
|
||
|
; ecx = number of bytes left, the iteration starts only if ecx is nonzero,
|
||
|
; edx = size of the current descriptor.
|
||
|
; 7a. The first byte is always accessible; it contains the length of
|
||
|
; the current descriptor. Validate that the length is at least 2 bytes,
|
||
|
; and the entire descriptor is readable (the length is at most number of
|
||
|
; bytes left).
|
||
|
movzx edx, [eax+usb_descr.bLength]
|
||
|
cmp edx, sizeof.usb_descr
|
||
|
jb .invalid
|
||
|
cmp ecx, edx
|
||
|
jb .invalid
|
||
|
; 7b. Check descriptor type. Ignore all non-INTERFACE descriptor.
|
||
|
cmp byte [eax+usb_descr.bDescriptorType], USB_INTERFACE_DESCR
|
||
|
jz .interface
|
||
|
.next_descriptor:
|
||
|
; 7c. Advance pointer, decrease length left, if there is still something left,
|
||
|
; continue the loop.
|
||
|
add eax, edx
|
||
|
sub ecx, edx
|
||
|
jnz .descriptor_loop
|
||
|
.done:
|
||
|
.nothing:
|
||
|
pop edi ebx ; restore used registers to be stdcall
|
||
|
ret
|
||
|
.interface:
|
||
|
; 7d. Validate the descriptor length.
|
||
|
cmp edx, sizeof.usb_interface_descr
|
||
|
jb .next_descriptor
|
||
|
; 7e. If bAlternateSetting is nonzero, this descriptor actually describes
|
||
|
; another mode of already known interface and belongs to the already loaded
|
||
|
; driver; amuse the user and continue to 7c.
|
||
|
cmp byte [eax+usb_interface_descr.bAlternateSetting], 0
|
||
|
jz @f
|
||
|
DEBUGF 1,'K : note: alternate setting with %x/%x/%x\n',\
|
||
|
[eax+usb_interface_descr.bInterfaceClass]:2,\
|
||
|
[eax+usb_interface_descr.bInterfaceSubClass]:2,\
|
||
|
[eax+usb_interface_descr.bInterfaceProtocol]:2
|
||
|
jmp .next_descriptor
|
||
|
@@:
|
||
|
; 7f. Check that the new interface does not overflow allocated table.
|
||
|
mov edx, [NumInterfaces]
|
||
|
inc dl
|
||
|
jz .invalid
|
||
|
cmp dl, [ebx+usb_device_data.NumInterfaces]
|
||
|
ja .invalid
|
||
|
; 7g. We have found a new interface. Advance bookkeeping vars.
|
||
|
mov [NumInterfaces], edx
|
||
|
add [InterfacesData], sizeof.usb_interface_data
|
||
|
; 7h. Save length left and pointer to the current interface descriptor.
|
||
|
push ecx eax
|
||
|
; Amuse the user if she is watching the debug board.
|
||
|
DEBUGF 1,'K : USB interface class/subclass/protocol = %x/%x/%x\n',\
|
||
|
[eax+usb_interface_descr.bInterfaceClass]:2,\
|
||
|
[eax+usb_interface_descr.bInterfaceSubClass]:2,\
|
||
|
[eax+usb_interface_descr.bInterfaceProtocol]:2
|
||
|
; 7i. Select the correct driver based on interface class.
|
||
|
; For hubs, go to 7j. Otherwise, go to 7k.
|
||
|
; Note: this should be rewritten as table-based lookup when more drivers will
|
||
|
; be available.
|
||
|
cmp byte [eax+usb_interface_descr.bInterfaceClass], 9
|
||
|
jz .found_hub
|
||
|
mov edx, usb_hid_name
|
||
|
cmp byte [eax+usb_interface_descr.bInterfaceClass], 3
|
||
|
jz .load_driver
|
||
|
mov edx, usb_print_name
|
||
|
cmp byte [eax+usb_interface_descr.bInterfaceClass], 7
|
||
|
jz .load_driver
|
||
|
mov edx, usb_stor_name
|
||
|
cmp byte [eax+usb_interface_descr.bInterfaceClass], 8
|
||
|
jz .load_driver
|
||
|
mov edx, usb_other_name
|
||
|
jmp .load_driver
|
||
|
.found_hub:
|
||
|
; 7j. Hubs are a part of USB stack, thus, integrated into the kernel.
|
||
|
; Use the pointer to hub callbacks and go to 7m.
|
||
|
mov eax, usb_hub_pseudosrv - USBSRV.usb_func
|
||
|
jmp .driver_loaded
|
||
|
.load_driver:
|
||
|
; 7k. Load the corresponding driver.
|
||
|
push ebx esi edi
|
||
|
stdcall get_service, edx
|
||
|
pop edi esi ebx
|
||
|
; 7l. If failed, say something to the debug board and go to 7p.
|
||
|
test eax, eax
|
||
|
jnz .driver_loaded
|
||
|
dbgstr 'failed to load class driver'
|
||
|
jmp .next_descriptor2
|
||
|
.driver_loaded:
|
||
|
; 7m. Call AddDevice function of the driver.
|
||
|
; Note that top of stack contains a pointer to the current interface,
|
||
|
; saved by step 7h.
|
||
|
mov [driver], eax
|
||
|
mov eax, [eax+USBSRV.usb_func]
|
||
|
pop edx
|
||
|
push edx
|
||
|
; Note: usb_hub_init assumes that edx points to usb_interface_descr,
|
||
|
; ecx = length rest; if you change the code, modify usb_hub_init also.
|
||
|
stdcall [eax+USBFUNC.add_device], [pipe], [calldata], edx
|
||
|
; 7n. If failed, say something to the debug board and go to 7p.
|
||
|
test eax, eax
|
||
|
jnz .store_data
|
||
|
dbgstr 'USB device initialization failed'
|
||
|
jmp .next_descriptor2
|
||
|
.store_data:
|
||
|
; 7o. Store the returned value and the driver handle to InterfacesData.
|
||
|
; Note that step 7g has already advanced InterfacesData.
|
||
|
mov edx, [InterfacesData]
|
||
|
mov [edx+usb_interface_data.DriverData-sizeof.usb_interface_data], eax
|
||
|
mov eax, [driver]
|
||
|
mov [edx+usb_interface_data.DriverFunc-sizeof.usb_interface_data], eax
|
||
|
.next_descriptor2:
|
||
|
; 7p. Restore registers saved in step 7h, get the descriptor length and
|
||
|
; continue to 7c.
|
||
|
pop eax ecx
|
||
|
movzx edx, byte [eax+usb_descr.bLength]
|
||
|
jmp .next_descriptor
|
||
|
endp
|
||
|
|
||
|
; Driver names, see step 7i of usb_got_config_callback.
|
||
|
iglobal
|
||
|
usb_hid_name db 'usbhid',0
|
||
|
usb_stor_name db 'usbstor',0
|
||
|
usb_print_name db 'usbprint',0
|
||
|
usb_other_name db 'usbother',0
|
||
|
endg
|