include/usbhost/usbhost.h - android-core - Git at Google

 /*
  * Copyright (C) 2010 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #ifndef __USB_HOST_H
 #define __USB_HOST_H

 #ifdef __cplusplus
 extern "C" {
 #endif

 #include <stdint.h>

 #include <linux/version.h>
 #if LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 20)
 #include <linux/usb/ch9.h>
 #else
 #include <linux/usb_ch9.h>
 #endif

 struct usb_host_context;
 struct usb_endpoint_descriptor;

 struct usb_descriptor_iter {
     unsigned char*  config;
     unsigned char*  config_end;
     unsigned char*  curr_desc;
 };

 struct usb_request
 {
     struct usb_device *dev;
     void* buffer;
     int buffer_length;
     int actual_length;
     int max_packet_size;
     void *private_data; /* struct usbdevfs_urb* */
     int endpoint;
     void *client_data;  /* free for use by client */
 };

 /* Callback for notification when new USB devices are attached.
  * Return true to exit from usb_host_run.
  */
 typedef int (* usb_device_added_cb)(const char *dev_name, void *client_data);

 /* Callback for notification when USB devices are removed.
  * Return true to exit from usb_host_run.
  */
 typedef int (* usb_device_removed_cb)(const char *dev_name, void *client_data);

 /* Callback indicating that initial device discovery is done.
  * Return true to exit from usb_host_run.
  */
 typedef int (* usb_discovery_done_cb)(void *client_data);

 /* Call this to initialize the USB host library. */
 struct usb_host_context *usb_host_init(void);

 /* Call this to cleanup the USB host library. */
 void usb_host_cleanup(struct usb_host_context *context);

 /* Call this to get the inotify file descriptor. */
 int usb_host_get_fd(struct usb_host_context *context);

 /* Call this to initialize the usb host context. */
 int usb_host_load(struct usb_host_context *context,
                   usb_device_added_cb added_cb,
                   usb_device_removed_cb removed_cb,
                   usb_discovery_done_cb discovery_done_cb,
                   void *client_data);

 /* Call this to read and handle occuring usb event. */
 int usb_host_read_event(struct usb_host_context *context);

 /* Call this to monitor the USB bus for new and removed devices.
  * This is intended to be called from a dedicated thread,
  * as it will not return until one of the callbacks returns true.
  * added_cb will be called immediately for each existing USB device,
  * and subsequently each time a new device is added.
  * removed_cb is called when USB devices are removed from the bus.
  * discovery_done_cb is called after the initial discovery of already
  * connected devices is complete.
  */
 void usb_host_run(struct usb_host_context *context,
                   usb_device_added_cb added_cb,
                   usb_device_removed_cb removed_cb,
                   usb_discovery_done_cb discovery_done_cb,
                   void *client_data);

 /* Creates a usb_device object for a USB device */
 struct usb_device *usb_device_open(const char *dev_name);

 /* Releases all resources associated with the USB device */
 void usb_device_close(struct usb_device *device);

 /* Creates a usb_device object for already open USB device */
 struct usb_device *usb_device_new(const char *dev_name, int fd);

 /* Returns the file descriptor for the usb_device */
 int usb_device_get_fd(struct usb_device *device);

 /* Returns the name for the USB device, which is the same as
  * the dev_name passed to usb_device_open()
  */
 const char* usb_device_get_name(struct usb_device *device);

 /* Returns a unique ID for the device.
  *Currently this is generated from the dev_name path.
  */
 int usb_device_get_unique_id(struct usb_device *device);

 /* Returns a unique ID for the device name.
  * Currently this is generated from the device path.
  */
 int usb_device_get_unique_id_from_name(const char* name);

 /* Returns the device name for the unique ID.
  * Call free() to deallocate the returned string */
 char* usb_device_get_name_from_unique_id(int id);

 /* Returns the USB vendor ID from the device descriptor for the USB device */
 uint16_t usb_device_get_vendor_id(struct usb_device *device);

 /* Returns the USB product ID from the device descriptor for the USB device */
 uint16_t usb_device_get_product_id(struct usb_device *device);

 const struct usb_device_descriptor* usb_device_get_device_descriptor(struct usb_device *device);

 /* Returns a USB descriptor string for the given string ID.
  * Used to implement usb_device_get_manufacturer_name,
  * usb_device_get_product_name and usb_device_get_serial.
  * Call free() to free the result when you are done with it.
  */
 char* usb_device_get_string(struct usb_device *device, int id);

 /* Returns the manufacturer name for the USB device.
  * Call free() to free the result when you are done with it.
  */
 char* usb_device_get_manufacturer_name(struct usb_device *device);

 /* Returns the product name for the USB device.
  * Call free() to free the result when you are done with it.
  */
 char* usb_device_get_product_name(struct usb_device *device);

 /* Returns the version number for the USB device.
  */
 int usb_device_get_version(struct usb_device *device);

 /* Returns the USB serial number for the USB device.
  * Call free() to free the result when you are done with it.
  */
 char* usb_device_get_serial(struct usb_device *device);

 /* Returns true if we have write access to the USB device,
  * and false if we only have access to the USB device configuration.
  */
 int usb_device_is_writeable(struct usb_device *device);

 /* Initializes a usb_descriptor_iter, which can be used to iterate through all
  * the USB descriptors for a USB device.
  */
 void usb_descriptor_iter_init(struct usb_device *device, struct usb_descriptor_iter *iter);

 /* Returns the next USB descriptor for a device, or NULL if we have reached the
  * end of the list.
  */
 struct usb_descriptor_header *usb_descriptor_iter_next(struct usb_descriptor_iter *iter);

 /* Claims the specified interface of a USB device */
 int usb_device_claim_interface(struct usb_device *device, unsigned int interface);

 /* Releases the specified interface of a USB device */
 int usb_device_release_interface(struct usb_device *device, unsigned int interface);

 /* Requests the kernel to connect or disconnect its driver for the specified interface.
  * This can be used to ask the kernel to disconnect its driver for a device
  * so usb_device_claim_interface can claim it instead.
  */
 int usb_device_connect_kernel_driver(struct usb_device *device,
         unsigned int interface, int connect);

 /* Sets the current configuration for the device to the specified configuration */
 int usb_device_set_configuration(struct usb_device *device, int configuration);

 /* Sets the specified interface of a USB device */
 int usb_device_set_interface(struct usb_device *device, unsigned int interface,
                             unsigned int alt_setting);

 /* Sends a control message to the specified device on endpoint zero */
 int usb_device_control_transfer(struct usb_device *device,
                             int requestType,
                             int request,
                             int value,
                             int index,
                             void* buffer,
                             int length,
                             unsigned int timeout);

 /* Reads or writes on a bulk endpoint.
  * Returns number of bytes transferred, or negative value for error.
  */
 int usb_device_bulk_transfer(struct usb_device *device,
                             int endpoint,
                             void* buffer,
                             int length,
                             unsigned int timeout);

 /* Creates a new usb_request. */
 struct usb_request *usb_request_new(struct usb_device *dev,
         const struct usb_endpoint_descriptor *ep_desc);

 /* Releases all resources associated with the request */
 void usb_request_free(struct usb_request *req);

 /* Submits a read or write request on the specified device */
 int usb_request_queue(struct usb_request *req);

  /* Waits for the results of a previous usb_request_queue operation.
   * Returns a usb_request, or NULL for error.
   */
 struct usb_request *usb_request_wait(struct usb_device *dev);

 /* Cancels a pending usb_request_queue() operation. */
 int usb_request_cancel(struct usb_request *req);

 #ifdef __cplusplus
 }
 #endif
 #endif /* __USB_HOST_H */
	/*
	* Copyright (C) 2010 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#ifndef __USB_HOST_H
	#define __USB_HOST_H

	#ifdef __cplusplus
	extern "C" {
	#endif

	#include <stdint.h>

	#include <linux/version.h>
	#if LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 20)
	#include <linux/usb/ch9.h>
	#else
	#include <linux/usb_ch9.h>
	#endif

	struct usb_host_context;
	struct usb_endpoint_descriptor;

	struct usb_descriptor_iter {
	unsigned char* config;
	unsigned char* config_end;
	unsigned char* curr_desc;
	};

	struct usb_request
	{
	struct usb_device *dev;
	void* buffer;
	int buffer_length;
	int actual_length;
	int max_packet_size;
	void private_data; / struct usbdevfs_urb* */
	int endpoint;
	void client_data; / free for use by client */
	};

	/* Callback for notification when new USB devices are attached.
	* Return true to exit from usb_host_run.
	*/
	typedef int (* usb_device_added_cb)(const char dev_name, void client_data);

	/* Callback for notification when USB devices are removed.
	* Return true to exit from usb_host_run.
	*/
	typedef int (* usb_device_removed_cb)(const char dev_name, void client_data);

	/* Callback indicating that initial device discovery is done.
	* Return true to exit from usb_host_run.
	*/
	typedef int (* usb_discovery_done_cb)(void *client_data);

	/* Call this to initialize the USB host library. */
	struct usb_host_context *usb_host_init(void);

	/* Call this to cleanup the USB host library. */
	void usb_host_cleanup(struct usb_host_context *context);

	/* Call this to get the inotify file descriptor. */
	int usb_host_get_fd(struct usb_host_context *context);

	/* Call this to initialize the usb host context. */
	int usb_host_load(struct usb_host_context *context,
	usb_device_added_cb added_cb,
	usb_device_removed_cb removed_cb,
	usb_discovery_done_cb discovery_done_cb,
	void *client_data);

	/* Call this to read and handle occuring usb event. */
	int usb_host_read_event(struct usb_host_context *context);

	/* Call this to monitor the USB bus for new and removed devices.
	* This is intended to be called from a dedicated thread,
	* as it will not return until one of the callbacks returns true.
	* added_cb will be called immediately for each existing USB device,
	* and subsequently each time a new device is added.
	* removed_cb is called when USB devices are removed from the bus.
	* discovery_done_cb is called after the initial discovery of already
	* connected devices is complete.
	*/
	void usb_host_run(struct usb_host_context *context,
	usb_device_added_cb added_cb,
	usb_device_removed_cb removed_cb,
	usb_discovery_done_cb discovery_done_cb,
	void *client_data);

	/* Creates a usb_device object for a USB device */
	struct usb_device usb_device_open(const char dev_name);

	/* Releases all resources associated with the USB device */
	void usb_device_close(struct usb_device *device);

	/* Creates a usb_device object for already open USB device */
	struct usb_device usb_device_new(const char dev_name, int fd);

	/* Returns the file descriptor for the usb_device */
	int usb_device_get_fd(struct usb_device *device);

	/* Returns the name for the USB device, which is the same as
	* the dev_name passed to usb_device_open()
	*/
	const char* usb_device_get_name(struct usb_device *device);

	/* Returns a unique ID for the device.
	*Currently this is generated from the dev_name path.
	*/
	int usb_device_get_unique_id(struct usb_device *device);

	/* Returns a unique ID for the device name.
	* Currently this is generated from the device path.
	*/
	int usb_device_get_unique_id_from_name(const char* name);

	/* Returns the device name for the unique ID.
	* Call free() to deallocate the returned string */
	char* usb_device_get_name_from_unique_id(int id);

	/* Returns the USB vendor ID from the device descriptor for the USB device */
	uint16_t usb_device_get_vendor_id(struct usb_device *device);

	/* Returns the USB product ID from the device descriptor for the USB device */
	uint16_t usb_device_get_product_id(struct usb_device *device);

	const struct usb_device_descriptor* usb_device_get_device_descriptor(struct usb_device *device);

	/* Returns a USB descriptor string for the given string ID.
	* Used to implement usb_device_get_manufacturer_name,
	* usb_device_get_product_name and usb_device_get_serial.
	* Call free() to free the result when you are done with it.
	*/
	char* usb_device_get_string(struct usb_device *device, int id);

	/* Returns the manufacturer name for the USB device.
	* Call free() to free the result when you are done with it.
	*/
	char* usb_device_get_manufacturer_name(struct usb_device *device);

	/* Returns the product name for the USB device.
	* Call free() to free the result when you are done with it.
	*/
	char* usb_device_get_product_name(struct usb_device *device);

	/* Returns the version number for the USB device.
	*/
	int usb_device_get_version(struct usb_device *device);

	/* Returns the USB serial number for the USB device.
	* Call free() to free the result when you are done with it.
	*/
	char* usb_device_get_serial(struct usb_device *device);

	/* Returns true if we have write access to the USB device,
	* and false if we only have access to the USB device configuration.
	*/
	int usb_device_is_writeable(struct usb_device *device);

	/* Initializes a usb_descriptor_iter, which can be used to iterate through all
	* the USB descriptors for a USB device.
	*/
	void usb_descriptor_iter_init(struct usb_device device, struct usb_descriptor_iter iter);

	/* Returns the next USB descriptor for a device, or NULL if we have reached the
	* end of the list.
	*/
	struct usb_descriptor_header usb_descriptor_iter_next(struct usb_descriptor_iter iter);

	/* Claims the specified interface of a USB device */
	int usb_device_claim_interface(struct usb_device *device, unsigned int interface);

	/* Releases the specified interface of a USB device */
	int usb_device_release_interface(struct usb_device *device, unsigned int interface);

	/* Requests the kernel to connect or disconnect its driver for the specified interface.
	* This can be used to ask the kernel to disconnect its driver for a device
	* so usb_device_claim_interface can claim it instead.
	*/
	int usb_device_connect_kernel_driver(struct usb_device *device,
	unsigned int interface, int connect);

	/* Sets the current configuration for the device to the specified configuration */
	int usb_device_set_configuration(struct usb_device *device, int configuration);

	/* Sets the specified interface of a USB device */
	int usb_device_set_interface(struct usb_device *device, unsigned int interface,
	unsigned int alt_setting);

	/* Sends a control message to the specified device on endpoint zero */
	int usb_device_control_transfer(struct usb_device *device,
	int requestType,
	int request,
	int value,
	int index,
	void* buffer,
	int length,
	unsigned int timeout);

	/* Reads or writes on a bulk endpoint.
	* Returns number of bytes transferred, or negative value for error.
	*/
	int usb_device_bulk_transfer(struct usb_device *device,
	int endpoint,
	void* buffer,
	int length,
	unsigned int timeout);

	/* Creates a new usb_request. */
	struct usb_request usb_request_new(struct usb_device dev,
	const struct usb_endpoint_descriptor *ep_desc);

	/* Releases all resources associated with the request */
	void usb_request_free(struct usb_request *req);

	/* Submits a read or write request on the specified device */
	int usb_request_queue(struct usb_request *req);

	/* Waits for the results of a previous usb_request_queue operation.
	* Returns a usb_request, or NULL for error.
	*/
	struct usb_request usb_request_wait(struct usb_device dev);

	/* Cancels a pending usb_request_queue() operation. */
	int usb_request_cancel(struct usb_request *req);

	#ifdef __cplusplus
	}
	#endif
	#endif /* __USB_HOST_H */