RL-USB Host Functions

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The following RL-USB Host Functions are important to understand the RL-USB Host Software Stack. RL-USB Host functions are categorized into:

• Core functions
  
  initialize and run the USB Host Core. These functions are part of the RL-USB Library.
  
  

  Function Name	Description
  usbh_init	Initializes the USB Host Stack and USB Host Controller Hardware.
  usbh_init_all	Initializes the USB Host Stack and all of the USB Host Controllers Hardware.
  usbh_uninit	Uninitializes the USB Host Stack and USB Host Controller Hardware.
  usbh_uninit_all	Uninitializes the USB Host Stack and all of the USB Host Controllers Hardware.
  usbh_engine	Handles USB Host events and executes enumeration.
  usbh_engine_all	Handles USB Hosts events and executes enumeration.
  usbh_get_last_error	Returns last error that happened on the USB Host Core.
  usbh_get_error_string	Returns string with name of requested error code.

• Memory management functions
  
  provide simple memory management for the USB Host stack.
  
  

  Function Name	Description
  usbh_mem_init	Initializes the memory pool.
  usbh_mem_alloc	Allocates a block of memory form the memory pool.
  usbh_mem_free	Frees a previously allocated block of memory.

• OHCI Compliant USB Host Controller Hardware layer functions
  
  interact with the OHCI USB Host Controller Hardware. In most cases, these functions are provided in an external module for devices that have an OHCI compliant USB Host Controller. For devices without this module, adapt the functions manually. Provided modules are located in the folder \ARM\RL\USB\Drivers and have the name usbh_ohci_device family name.c.
  
  

  Function Name	Description
  get_capabilities	Report driver capabilities.
  delay_ms	Delays execution for a specified time in milliseconds.
  reg_wr	Writes data to the OHCI register.
  reg_rd	Reads data from the OHCI register.
  pins_config	Configures or unconfigures pins used by the OHCI Controller.
  init	Initializes or uninitializes the OHCI Controller. For example: clocks.
  port_power	Drives port power pin on or off (VBUS).
  irq_en	Enables or disables the OHCI Controller interrupt.

• Custom EHCI for NXP devices USB Host Controller Hardware layer functions
  
  interact with the custom EHCI for NXP devices USB Host Controller Hardware. In most cases, these functions are provided in an external module for devices that have an custom EHCI for NXP devices compliant USB Host Controller. For devices without this module, adapt the functions manually. Provided modules are located in the folder \ARM\RL\USB\Drivers and have the name usbh_ehci_device family name.c.
  
  

  Function Name	Description
  get_capabilities	Report driver capabilities.
  delay_ms	Delays execution for a specified time in milliseconds.
  reg_wr	Writes data to the EHCI register.
  reg_rd	Reads data from the EHCI register.
  pins_config	Configures or unconfigures pins used by the EHCI Controller.
  init	Initializes or uninitializes the EHCI Controller. For example: clocks.
  port_power	Drives port power pin on or off (VBUS).
  irq_en	Enables or disables the EHCI Controller interrupt.

• Custom USB Host Controller Hardware layer functions
  
  interact with the Custom USB Host Controller Hardware. In most cases, these functions are provided in an external module for devices that have Custom USB Host Controller. For devices without this module, adapt the functions manually. Provided modules are located in the folder \ARM\RL\USB\Drivers and have the name usbh_device family name.c.
  
  

  Function Name	Description
  get_capabilities	Report driver capabilities.
  delay_ms	Delays execution for a specified time in milliseconds.
  pins_config	Configures or unconfigures pins used by the USB Host Controller.
  init	Initializes or uninitializes the USB Host Controller. For example: clocks.
  port_power	Drives port power pin on or off (VBUS).
  port_reset	Do a port reset.
  get_connect	Get the port connection status.
  get_speed	Get the port enumerated speed.
  ep_add	Add endpoint.
  ep_config	Configure endpoint.
  ep_remove	Remove endpoint.
  urb_submit	Submit the communication request.
  urb_cancel	Cancel the communication request.

• HID Class specific functions
  
  enable the USB Host to support USB Human Interface Devices.
  
  

  Function Name	Description
  usbh_hid_status	Returns the HID device connection status.
  usbh_hid_data_in	Retrieves the raw data received from the HID device.
  usbh_hid_data_out	Sends the raw data to the HID device.
  usbh_hid_kbd_getkey	Retrieves the signals sent by a USB keyboard.
  usbh_hid_mouse_getdata	Retrieves the signals sent by a USB mouse.
  usbh_hid_parse_report_desc	Enables user to analyze report descriptor.
  usbh_hid_data_in_callback	Enables user to analyze and act upon received report data.
  usbh_hid_get_last_error	Returns last error that happened on the human interface device instance.

• MSC Class specific functions
  
  enable the USB Host to support USB Mass Storage Devices.
  
  

  Function Name	Description
  usbh_msc_status	Returns the MSC device connection status.
  usbh_msc_write	Writes data from a buffer to MSC device sectors.
  usbh_msc_read	Reads MSC device sector data into a buffer.
  usbh_msc_read_config	Reads the USB MSC device configuration and checks whether the device is compatible with the Flash File System.
  usbh_msc_get_last_error	Returns last error that happened on the mass storage device instance.

• USB Device Class specific functions
  
  enable the USB Host to support additional USB Device Class. Functions listed below provide class interface to the USB Host Core, also functions that provide application with class functionality need to be implemented but their names and functionality depend on class supported.
  
  

  Function Name	Description
  Config	Config function should configure resources for a device of specified class.
  UnConfig	UnConfig function should unconfigure resources previously configured for a device of specified class.
  Init	Init function should initialize the device of a specified class.
  UnInit	UnInit function should uninitialize the device of a specified class.
  GetLastError	GetLastError function should return the last error code of the device of specified class.