2 * Author: Brendan Le Foll <brendan.le.foll@intel.com>
3 * Copyright (c) 2014 Intel Corporation.
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29 * @brief Inter-Integrated Circuit
31 * This file defines the i2c/Iic interface for libmaa. A context represents a
32 * bus and that bus may contain multiple addresses or i2c slaves. It is
33 * considered best practice to make sure the address is correct before doing
34 * any calls on i2c, in case another application or even thread changed the
35 * addres on that bus. Multiple instances of the same bus can exist.
37 * @snippet i2c_HMC5883L.c Interesting
53 * Opaque pointer definition to the internal struct _i2c
55 typedef struct _i2c* maa_i2c_context;
57 /** Initialise i2c context, using board defintions
59 * @param bus i2c bus to use
60 * @return maa_i2c_context i2c context ready for other calls.
62 maa_i2c_context maa_i2c_init(int bus);
64 /** Initialise i2c context, passing in spi bus to use.
66 * @param bus The i2c bus to use i.e. /dev/i2c-2 would be "2"
67 * @return maa_i2c_context i2c context ready for other calls.
69 maa_i2c_context maa_i2c_init_raw(unsigned int bus);
71 /** Sets the frequency of the i2c context
73 * @param dev the i2c context
74 * @param hz The bus frequency in hertz
76 * @return maa_result_t the maa result.
78 maa_result_t maa_i2c_frequency(maa_i2c_context dev, int hz);
80 /** Read from an i2c context
82 * @param dev the i2c context
83 * @param data pointer to the byte array to read data in to
84 * @param length max number of bytes to read
86 * @return maa_result_t the maa result.
88 maa_result_t maa_i2c_read(maa_i2c_context dev, uint8_t *data, int length);
90 /** Read a single byte from the i2c context
92 * @param dev the i2c context
94 * @return byte the result of the read or -1 if failed.
96 uint8_t maa_i2c_read_byte(maa_i2c_context dev);
98 /** Write to an i2c context
100 * @param dev the i2c context
101 * @param data pointer to the byte array to be written
102 * @param length the number of bytes to transmit
104 * @return maa_result_t the maa result.
106 maa_result_t maa_i2c_write(maa_i2c_context dev, const uint8_t *data, int length);
108 /** Write a single byte to an i2c context
110 * @param dev the i2c context
111 * @data the byte to write
113 * @return maa_result_t the maa result.
115 maa_result_t maa_i2c_write_byte(maa_i2c_context dev, const uint8_t data);
117 /** Sets the i2c context address.
119 * @param dev the i2c context
120 * @param address The address to set for the slave (ignoring the least
121 * signifcant bit). If set to 0, the slave will only respond to the
122 * general call address.
124 * @return maa_result_t the maa result.
126 maa_result_t maa_i2c_address(maa_i2c_context dev, int address);
128 /** De-inits an maa_i2c_context device
130 * @param dev the i2c context
132 * @return maa_result_t the maa result.
134 maa_result_t maa_i2c_stop(maa_i2c_context dev);