nuttx-5.15 Release Notes: +
nuttx-5.16 Release Notes:
- This 62nd release of NuttX, Version 5.15, was made on December12, 2010 and is available for download from the + The 63rd release of NuttX, Version 5.16, was made on January 10, 2010 and is available for download from the SourceForge website. The change log associated with the release is available here. Unreleased changes after this release are available in CVS. These unreleased changes are listed here.
- This release includes several bugfixes as well as feature enhancements, primarily for the Olimex LPC1766-STK board. - Important bugfxes included: -
send() logic, now checks if the destination IP address is in the ARP table before sending the packet;
- an ARP request will go out instead of the TCP packet.
- This improves behavior, for example, on the first on the first GET request from a browser
- - And feature enhancements: + Below is a summary of the NuttX USB host implementation as extracted from the + NuttX Porting Guide: +
+
+ include/nuttx/usb/usbhost.h.
+ All structures and APIs needed to work with USB host-side drivers are provided in this header file.
+
+ struct usbhost_driver_s.
+ Each USB host controller driver must implement an instance of struct usbhost_driver_s.
+ This structure is defined in include/nuttx/usb/usbhost.h.
+
+ Examples:
+ arch/arm/src/lpc17xx/lpc17_usbhost.c.
+
+ struct usbhost_class_s.
+ Each USB host class driver must implement an instance of struct usbhost_class_s.
+ This structure is also defined in include/nuttx/usb/usbhost.h.
+
+ Examples:
+ drivers/usbhost/usbhost_storage.c
+
cmddata() method to the SPI interface.
- Some devices require an additional out-of-band bit to specify if the next word sent to the device is a command or data.
- The cmddata() method provides selection of command or data.
+
+ USB Host Class Driver Registry.
+ The NuttX USB host infrastructure includes a registry.
+ During its initialization, each USB host class driver must call the interface, usbhost_registerclass()
+ in order add its interface to the registery.
+ Later, when a USB device is connected, the USB host controller will look up the USB host class driver that is needed to support the connected device in this registry.
+
+ Examples:
+ drivers/usbhost/usbhost_registry.c, drivers/usbhost/usbhost_registerclass.c, and drivers/usbhost/usbhost_findclass.c,
+
+ Detection and Enumeration of Connected Devices. + Each USB host device controller supports two methods that are used to detect and enumeration newly connected devices + (and also detect disconnected devices): +
++
+ int (*wait)(FAR struct usbhost_driver_s *drvr, bool connected);
+
+ Wait for a device to be connected or disconnected. +
+
+ int (*enumerate)(FAR struct usbhost_driver_s *drvr);
+
+ Enumerate the connected device.
+ As part of this enumeration process, the driver will
+ (1) get the device's configuration descriptor,
+ (2) extract the class ID info from the configuration descriptor,
+ (3) call usbhost_findclass() to find the class that supports this device,
+ (4) call the create() method on the struct usbhost_registry_s interface to get a class instance, and
+ finally (5) call the connect() method of the struct usbhost_class_s interface.
+ After that, the class is in charge of the sequence of operations.
+
+ Binding USB Host-Side Drivers.
+ USB host-side controller drivers are not normally directly accessed by user code,
+ but are usually bound to another, higher level USB host class driver.
+ The class driver exports the standard NuttX device interface so that the connected USB device can be accessed just as with other, similar, on-board devices.
+ For example, the USB host mass storage class driver (drivers/usbhost/usbhost_storage.c) will register a standard, NuttX block driver interface (like /dev/sda)
+ that can be used to mount a file system just as with any other other block driver instance.
+ In general, the binding sequence is:
+
+
+ Each USB host class driver includes an intialization entry point that is called from the
+ application at initialization time.
+ This driver calls usbhost_registerclass() during this initialization in order to makes itself available in the event the the device that it supports is connected.
+
+ Examples:
+ The function usbhost_storageinit() in the file drivers/usbhost/usbhost_storage.c
+
+ Each application must include a waiter thread thread that (1) calls the USB host controller driver's wait() to detect the connection of a device, and then
+ (2) call the USB host controller driver's enumerate method to bind the registered USB host class driver to the USB host controller driver.
+
+ Examples:
+ The function nsh_waiter() in the file configs/nucleus2g/src/up_nsh.c and
+ the function nsh_waiter() in the file configs/olimex-lpc1766stk/src/up_nsh.c.
+
+ As part of its operation during the binding operation, the USB host class driver will register an instances of a standard NuttX driver under the /dev directory.
+ To repeat the above example, the USB host mass storage class driver (drivers/usbhost/usbhost_storage.c) will register a standard, NuttX block driver interface (like /dev/sda)
+ that can be used to mount a file system just as with any other other block driver instance.
+
+ Examples:
+ See the call to register_blockdriver() in the function usbhost_initvolume() in the file drivers/usbhost/usbhost_storage.c.
+