Abstract interface to physical USB hardware. More...

#include <USBPhy.h>

Public Member Functions
virtual void	init (USBPhyEvents *events)=0
	Initialize this USBPhy instance. More...

virtual void	deinit ()=0
	Power down this USBPhy instance. More...

virtual bool	powered ()=0
	Check if USB power is present. More...

virtual void	connect ()=0
	Make the USB phy visible to the USB host. More...

virtual void	disconnect ()=0
	Detach the USB phy. More...

virtual void	configure ()=0
	Set this device to the configured state. More...

virtual void	unconfigure ()=0
	Leave the configured state. More...

virtual void	sof_enable ()=0
	Enable the start of frame interrupt. More...

virtual void	sof_disable ()=0
	Disable the start of frame interrupt. More...

virtual void	set_address (uint8_t address)=0
	Set the USBPhy's address. More...

virtual void	remote_wakeup ()=0
	Wake upstream devices. More...

virtual const usb_ep_table_t *	endpoint_table ()=0
	Get the endpoint table. More...

virtual uint32_t	ep0_set_max_packet (uint32_t max_packet)=0
	Set wMaxPacketSize of endpoint 0. More...

virtual void	ep0_setup_read_result (uint8_t *buffer, uint32_t size)=0
	Read the contents of the SETUP packet. More...

virtual void	ep0_read (uint8_t *data, uint32_t size)=0
	Start receiving a packet of up to wMaxPacketSize on endpoint 0. More...

virtual uint32_t	ep0_read_result ()=0
	Read the contents of a received packet. More...

virtual void	ep0_write (uint8_t *buffer, uint32_t size)=0
	Write a packet on endpoint 0. More...

virtual void	ep0_stall ()=0
	Protocol stall on endpoint 0. More...

virtual bool	endpoint_add (usb_ep_t endpoint, uint32_t max_packet, usb_ep_type_t type)=0
	Configure and enable an endpoint. More...

virtual void	endpoint_remove (usb_ep_t endpoint)=0
	Disable an endpoint. More...

virtual void	endpoint_stall (usb_ep_t endpoint)=0
	Perform a functional stall on the given endpoint. More...

virtual void	endpoint_unstall (usb_ep_t endpoint)=0
	Unstall the endpoint. More...

virtual bool	endpoint_read (usb_ep_t endpoint, uint8_t *data, uint32_t size)=0
	Start a read on the given endpoint. More...

virtual uint32_t	endpoint_read_result (usb_ep_t endpoint)=0
	Finish a read on the given endpoint. More...

virtual bool	endpoint_write (usb_ep_t endpoint, uint8_t *data, uint32_t size)=0
	Start a write on the given endpoint. More...

virtual void	endpoint_abort (usb_ep_t endpoint)=0
	Abort the current transfer if it has not yet been sent. More...

virtual void	process ()=0
	Callback used for performing USB processing. More...

Detailed Description

Abstract interface to physical USB hardware.

Defined behavior

You can use any endpoint configurations that fit in the parameters of the table returned by USBPhy::endpoint_table.
You can use all endpoints in any valid endpoint configuration concurrently.
The device supports use of at least one control, bulk, interrupt and isochronous in each direction at the same time - at least 8 endpoints.
USBPhy supports all standard endpoint sizes (wMaxPacketSize).
USBPhy can handle an interrupt latency of at least 100ms if the host PC is not performing a reset or setting the device's address.
USBPhy only sends USBPhyEvents when it is in the initialized state.
When unpowered, USBPhy only sends the USBPhyEvents::power event.
On USB reset, all endpoints are removed except for endpoint 0.
A call to USBPhy::ep0_write results in the call of USBPhyEvents::in when the PC reads the data unless a power loss, reset, or a call to USBPhy::disconnect occurs first.
A call to USBPhy::endpoint_write results in the call of USBPhyEvents::in when the pc reads the data unless a power loss, reset, or a call to USBPhy::endpoint_abort occurs first.
A call to USBPhy::endpoint_read results in the call of USBPhyEvents::out when the pc sends data unless a power loss, reset, or a call to USBPhy::endpoint_abort occurs first.
Endpoint 0 naks all transactions aside from setup packets until higher-level code calls one of USBPhy::ep0_read, USBPhy::ep0_write or USBPhy::ep0_stall.
Endpoint 0 stall automatically clears on reception of a setup packet.

Undefined behavior

Calling USBPhy::endpoint_add or USBPhy::endpoint_remove outside of the control requests SetInterface or SetConfiguration.
Calling USBPhy::endpoint_remove on an endpoint that has an ongoing read or write operation. To avoid undefined behavior, you must abort ongoing operations with USBPhy::endpoint_abort.
Devices behavior is undefined if latency is greater than 2ms when address is being set - see USB spec 9.2.6.3.
Devices behavior is undefined if latency is greater than 10ms when a reset occurs - see USB spec 7.1.7.5.
Calling any of the USBPhy::endpoint_* functions on endpoint 0.

Notes

Make sure USBPhy sends USBPhyEvents in the correct order when multiple packets are present. USBPhy must send IN endpoint events before OUT endpoint events if both are pending.
A host PC may resend setup packets to a USB device if there is noise on the USB line. The USBPhy should be able to handle this scenario and respond to the setup packet with an ACK.
Bidirectional protocols making use of alternating IN and OUT phases should not rely on the last ACK an IN transfer to indicate that the OUT phase should start. Instead, the OUT phase should be started at the same time the last IN transfer is started. This is because the ACK to the last in transfer may be dropped if there is noise on the USB line. If dropped, it will only be resent on the next IN phase. You can find more information on this in section 8.5.3.3 of the USB specification.

Definition at line 82 of file USBPhy.h.

Member Function Documentation

virtual void configure ( )

pure virtual

Set this device to the configured state.

Enable added endpoints if they are not enabled already.

virtual void connect ( )

pure virtual

Make the USB phy visible to the USB host.

Enable either the D+ or D- pullup so the host can detect the presence of this device.

virtual void deinit ( )

pure virtual

Power down this USBPhy instance.

Disable interrupts and stop sending events.

virtual void disconnect ( )

pure virtual

Detach the USB phy.

Disable the D+ and D- pullup and stop responding to USB traffic.

virtual void endpoint_abort ( usb_ep_t endpoint )

pure virtual

Abort the current transfer if it has not yet been sent.

Parameters

endpoint Endpoint to abort the transfer on. It is implementation defined if this function has an effect on receive endpoints.

virtual bool endpoint_add	(	usb_ep_t	endpoint,
		uint32_t	max_packet,
		usb_ep_type_t	type
	)

pure virtual

Configure and enable an endpoint.

Parameters

endpoint	Endpoint to configure and enable
max_packet	The maximum packet size that can be sent or received
type	The type of endpoint this should be configured as - USB_EP_TYPE_BULK, USB_EP_TYPE_INT or USB_EP_TYPE_ISO

Note: This function cannot be used to configure endpoint 0. That must be done with ep0_set_max_packet

virtual bool endpoint_read	(	usb_ep_t	endpoint,
		uint8_t *	data,
		uint32_t	size
	)

pure virtual

Start a read on the given endpoint.

Parameters

endpoint	Endpoint to start the read on
data	Buffer to fill with data
size	Size of the read buffer. This must be at least the max packet size for this endpoint.

Returns: true if the read was successfully started, false otherwise

virtual uint32_t endpoint_read_result ( usb_ep_t endpoint )

pure virtual

Finish a read on the given endpoint.

Parameters

endpoint Endpoint to check

Returns: The number of bytes received

virtual void endpoint_remove ( usb_ep_t endpoint )

pure virtual

Disable an endpoint.

Parameters

endpoint Endpoint to disable

virtual void endpoint_stall ( usb_ep_t endpoint )

pure virtual

Perform a functional stall on the given endpoint.

Set the HALT feature for this endpoint so that all further communication is aborted.

Parameters

endpoint Endpoint to stall

virtual const usb_ep_table_t* endpoint_table ( )

pure virtual

Get the endpoint table.

This function returns a table which describes the endpoints can be used, the functionality of those endpoints and the resource cost.

virtual void endpoint_unstall ( usb_ep_t endpoint )

pure virtual

Unstall the endpoint.

Clear the HALT feature on this endpoint so communication can resume.

Parameters

endpoint Endpoint to stall

virtual bool endpoint_write	(	usb_ep_t	endpoint,
		uint8_t *	data,
		uint32_t	size
	)

pure virtual

Start a write on the given endpoint.

Parameters

endpoint	Endpoint to write to
data	Buffer to write
size	Size of data to write

Returns: true if the data was prepared for transmit, false otherwise

virtual void ep0_read	(	uint8_t *	data,
		uint32_t	size
	)

pure virtual

Start receiving a packet of up to wMaxPacketSize on endpoint 0.

Parameters

data	Buffer to fill with the data read
size	Size of buffer

virtual uint32_t ep0_read_result ( )

pure virtual

Read the contents of a received packet.

Returns: Size of data read

virtual uint32_t ep0_set_max_packet ( uint32_t max_packet )

pure virtual

Set wMaxPacketSize of endpoint 0.

Parameters

max_packet The wMaxPacketSize value for endpoint 0

Returns: The actual size of endpoint 0

virtual void ep0_setup_read_result	(	uint8_t *	buffer,
		uint32_t	size
	)

pure virtual

Read the contents of the SETUP packet.

Parameters

buffer	Buffer to fill with data
size	Size of buffer passed in

virtual void ep0_stall ( )

pure virtual

Protocol stall on endpoint 0.

Stall all IN and OUT packets on endpoint 0 until a setup packet is received.

Note: The stall is cleared automatically when a setup packet is received

virtual void ep0_write	(	uint8_t *	buffer,
		uint32_t	size
	)

pure virtual

Write a packet on endpoint 0.

Parameters

buffer	Buffer fill with data to send
size	Size of data to send

virtual void init ( USBPhyEvents * events )

pure virtual

Initialize this USBPhy instance.

This function must be called before calling any other functions of this class, unless specifically noted.

Parameters

events Callback class to handle USB events

virtual bool powered ( )

pure virtual

Check if USB power is present.

Devices which don't support checking the USB power state must always return true.

Returns: true if USB power is present, false otherwise

virtual void process ( )

pure virtual

Callback used for performing USB processing.

USBPhy processing should be triggered by calling USBPhyEvents::start_process and done inside process. All USBPhyEvents callbacks aside from USBPhyEvents::start_process must be called in the context of process

virtual void remote_wakeup ( )

pure virtual

Wake upstream devices.

virtual void set_address ( uint8_t address )

pure virtual

Set the USBPhy's address.

Parameters

address This device's USB address

virtual void sof_disable ( )

pure virtual

Disable the start of frame interrupt.

Stop calling USBPhyEvents::sof.

virtual void sof_enable ( )

pure virtual

Enable the start of frame interrupt.

Call USBPhyEvents::sof on every frame.

virtual void unconfigure ( )

pure virtual

Leave the configured state.

This is a notification to the USBPhy indicating that the device is leaving the configured state. The USBPhy can disable all endpoints other than endpoint 0.

Public Member Functions

Detailed Description

Defined behavior

Undefined behavior

Notes

Member Function Documentation

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