usbhost.h revision 3af05b09eb116e48997a2d4611b0a1e033737d2e 
1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef __USB_HOST_H
18#define __USB_HOST_H
19
20#ifdef __cplusplus
21extern "C" {
22#endif
23
24#include <stdint.h>
25
26#include <linux/version.h>
27#if LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 20)
28#include <linux/usb/ch9.h>
29#else
30#include <linux/usb_ch9.h>
31#endif
32
33struct usb_host_context;
34struct usb_endpoint_descriptor;
35
36struct usb_descriptor_iter {
37    unsigned char*  config;
38    unsigned char*  config_end;
39    unsigned char*  curr_desc;
40};
41
42/* Callback for notification when new USB devices are attached.
43 * Return true to exit from usb_host_run.
44 */
45typedef int (* usb_device_added_cb)(const char *dev_name, void *client_data);
46
47/* Callback for notification when USB devices are removed.
48 * Return true to exit from usb_host_run.
49 */
50typedef int (* usb_device_removed_cb)(const char *dev_name, void *client_data);
51
52/* Callback indicating that initial device discovery is done.
53 * Return true to exit from usb_host_run.
54 */
55typedef int (* usb_discovery_done_cb)(void *client_data);
56
57/* Call this to initialize the USB host library. */
58struct usb_host_context *usb_host_init(void);
59
60/* Call this to cleanup the USB host library. */
61void usb_host_cleanup(struct usb_host_context *context);
62
63/* Call this to monitor the USB bus for new and removed devices.
64 * This is intended to be called from a dedicated thread,
65 * as it will not return until one of the callbacks returns true.
66 * added_cb will be called immediately for each existing USB device,
67 * and subsequently each time a new device is added.
68 * removed_cb is called when USB devices are removed from the bus.
69 * discovery_done_cb is called after the initial discovery of already
70 * connected devices is complete.
71 */
72void usb_host_run(struct usb_host_context *context,
73                  usb_device_added_cb added_cb,
74                  usb_device_removed_cb removed_cb,
75                  usb_discovery_done_cb discovery_done_cb,
76                  void *client_data);
77
78/* Creates a usb_device object for a USB device */
79struct usb_device *usb_device_open(const char *dev_name);
80
81/* Releases all resources associated with the USB device */
82void usb_device_close(struct usb_device *device);
83
84/* Returns the name for the USB device, which is the same as
85 * the dev_name passed to usb_device_open()
86 */
87const char* usb_device_get_name(struct usb_device *device);
88
89/* Returns a unique ID for the device.  Currently this is generated from the
90 * dev_name path.
91 */
92int usb_device_get_unique_id(struct usb_device *device);
93
94int usb_device_get_unique_id_from_name(const char* name);
95
96/* Returns the USB vendor ID from the device descriptor for the USB device */
97uint16_t usb_device_get_vendor_id(struct usb_device *device);
98
99/* Returns the USB product ID from the device descriptor for the USB device */
100uint16_t usb_device_get_product_id(struct usb_device *device);
101
102/* Sends a control message to the specified device on endpoint zero */
103int usb_device_send_control(struct usb_device *device,
104                            int requestType,
105                            int request,
106                            int value,
107                            int index,
108                            int length,
109                            void* buffer);
110
111/* Returns a USB descriptor string for the given string ID.
112 * Used to implement usb_device_get_manufacturer_name,
113 * usb_device_get_product_name and usb_device_get_serial.
114 * Call free() to free the result when you are done with it.
115 */
116char* usb_device_get_string(struct usb_device *device, int id);
117
118/* Returns the manufacturer name for the USB device.
119 * Call free() to free the result when you are done with it.
120 */
121char* usb_device_get_manufacturer_name(struct usb_device *device);
122
123/* Returns the product name for the USB device.
124 * Call free() to free the result when you are done with it.
125 */
126char* usb_device_get_product_name(struct usb_device *device);
127
128/* Returns the USB serial number for the USB device.
129 * Call free() to free the result when you are done with it.
130 */
131char* usb_device_get_serial(struct usb_device *device);
132
133/* Returns true if we have write access to the USB device,
134 * and false if we only have access to the USB device configuration.
135 */
136int usb_device_is_writeable(struct usb_device *device);
137
138/* Initializes a usb_descriptor_iter, which can be used to iterate through all
139 * the USB descriptors for a USB device.
140 */
141void usb_descriptor_iter_init(struct usb_device *device, struct usb_descriptor_iter *iter);
142
143/* Returns the next USB descriptor for a device, or NULL if we have reached the
144 * end of the list.
145 */
146struct usb_descriptor_header *usb_descriptor_iter_next(struct usb_descriptor_iter *iter);
147
148/* Claims the specified interface of a USB device */
149int usb_device_claim_interface(struct usb_device *device, unsigned int interface);
150
151/* Releases the specified interface of a USB device */
152int usb_device_release_interface(struct usb_device *device, unsigned int interface);
153
154
155/* Creates a new usb_endpoint for the specified endpoint of a USB device.
156 * This can be used to read or write data across the endpoint.
157 */
158struct usb_endpoint *usb_endpoint_open(struct usb_device *dev,
159                const struct usb_endpoint_descriptor *desc);
160
161/* Releases all resources associated with the endpoint */
162void usb_endpoint_close(struct usb_endpoint *ep);
163
164/* Begins a read or write operation on the specified endpoint */
165int usb_endpoint_queue(struct usb_endpoint *ep, void *data, int len);
166
167 /* Waits for the results of a previous usb_endpoint_queue operation on the
168  * specified endpoint.  Returns number of bytes transferred, or a negative
169  * value for error.
170  */
171int usb_endpoint_wait(struct usb_device *device, int *out_ep_num);
172
173/* Cancels a pending usb_endpoint_queue() operation on an endpoint. */
174int usb_endpoint_cancel(struct usb_endpoint *ep);
175
176/* Returns the usb_device for the given endpoint */
177struct usb_device *usb_endpoint_get_device(struct usb_endpoint *ep);
178
179/* Returns the endpoint address for the given endpoint */
180int usb_endpoint_number(struct usb_endpoint *ep);
181
182/* Returns the maximum packet size for the given endpoint.
183 * For bulk endpoints this should be 512 for highspeed or 64 for fullspeed.
184 */
185int usb_endpoint_max_packet(struct usb_endpoint *ep);
186
187#ifdef __cplusplus
188}
189#endif
190#endif /* __USB_HOST_H */
191