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33 .Nd I2C generic I/O device driver
41 device driver provides generic I/O to any
44 In order to control I2C devices, use
48 .Bl -tag -width ".Dv I2CRPTSTART"
50 .Pq Vt "struct iiccmd"
51 Sends the start condition to the slave specified by the
54 All other elements are ignored.
56 .Pq Vt "struct iiccmd"
57 Sends the repeated start condition to the slave specified by the
60 All other elements are ignored.
62 No argument is passed.
63 Sends the stop condition to the bus.
64 This terminates the current transaction.
66 .Pq Vt "struct iiccmd"
68 The argument is completely ignored.
70 .Pq Vt "struct iiccmd"
73 The bus should already be started.
79 element is the number of bytes to write.
82 element is a boolean flag.
83 It is non-zero when additional write commands will follow.
86 element is a pointer to the data to write to the bus.
88 .Pq Vt "struct iiccmd"
91 The bus should already be started.
97 element is the number of bytes to write.
100 element is a boolean flag.
101 It is non-zero when additional write commands will follow.
104 element is a pointer to where to store the data read from the bus.
105 Short reads on the bus produce undefined results.
107 .Pq Vt "struct iic_rdwr_data"
108 Generic read/write interface.
109 Allows for an arbitrary number of commands to be sent to
110 an arbitrary number of devices on the bus.
111 A read transfer is specified if
115 Otherwise the transfer is a write transfer.
118 element specifies the 7-bit address for the transfer.
121 element is the length of the data.
124 element is a buffer for that data.
125 This ioctl is intended to be
130 The following data structures are defined in
132 and referenced above:
133 .Bd -literal -offset indent
141 /* Designed to be compatible with linux's struct i2c_msg */
146 #define IIC_M_RD 0x0001 /* read vs write */
147 uint16_t len; /* msg length */
151 struct iic_rdwr_data {
152 struct iic_msg *msgs;
157 It is also possible to use read/write routines, then I2C start/stop handshake is
161 However, the address used for the read/write routines is the one
174 manual page first appeared in
179 manual page was written by
188 All other interfaces suffer from some kind of race.