1 /*
2 * Copyright (c) 2008 Travis Geiselbrecht
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining
5 * a copy of this software and associated documentation files
6 * (the "Software"), to deal in the Software without restriction,
7 * including without limitation the rights to use, copy, modify, merge,
8 * publish, distribute, sublicense, and/or sell copies of the Software,
9 * and to permit persons to whom the Software is furnished to do so,
10 * subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be
13 * included in all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
18 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
19 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
20 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
21 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
22 */
23 #ifndef __DEV_I2C_H
24 #define __DEV_I2C_H
25
26 #include <stdint.h>
27
28 #include <stddef.h> // size_t
29 #include <sys/types.h> // status_t
30
31 void i2c_init(void);
32 void i2c_init_early(void);
33
34 /* Notes about I2C addresses
35 * + Currently, there is no API support for 10-bit I2C addresses. 7-bit only.
36 * + Addresses should be supplied as the actual 7-bit address of the device.
37 * The platform driver is responsible for left shifting this address by 1 and
38 * suppling the appropriate value for the R/W bit.
39 */
40
41 /* send and receive blocks of data */
42 status_t i2c_transmit(int bus, uint8_t address, const void *buf, size_t count);
43 status_t i2c_receive(int bus, uint8_t address, void *buf, size_t count);
44
45 /* A few convenience routines based on the usual way of accessing registers on
46 * i2c slave devices.
47 */
48 status_t i2c_write_reg_bytes(int bus, uint8_t address, uint8_t reg, const uint8_t *val, size_t cnt);
49 status_t i2c_read_reg_bytes(int bus, uint8_t address, uint8_t reg, uint8_t *val, size_t cnt);
50
i2c_write_reg(int bus,uint8_t address,uint8_t reg,uint8_t val)51 static inline status_t i2c_write_reg(int bus, uint8_t address, uint8_t reg, uint8_t val)
52 {
53 return i2c_write_reg_bytes(bus, address, reg, &val, 1);
54 }
55
i2c_read_reg(int bus,uint8_t address,uint8_t reg,uint8_t * val)56 static inline status_t i2c_read_reg(int bus, uint8_t address, uint8_t reg, uint8_t *val)
57 {
58 return i2c_read_reg_bytes(bus, address, reg, val, 1);
59 }
60 #endif
61
62