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31 .Nd Dallas Semiconductor 1-Wire Controller
37 module implements Dallas Semiconductor 1-Wire signaling.
40 driver 1-Wire bus protocol.
43 device implements the Link Layer of the 1-Wire bus protocol stack.
45 Bit banging a pin on a
47 is the only supported controller.
48 Both standard and overdrive transfer timings are implemented.
49 Strong pull-up functionality needed to support parasitic mode is not
52 To enable 1-Wire for FDT systems requires modifying the DTS for your
53 board to add something like:
58 compatible = "w1-gpio";
65 The gpios property describes the GPIO pin the 1-Wire bus is connected
67 For more details about the
69 property, please consult
70 .Pa /usr/src/sys/dts/bindings-gpio.txt .
74 based system these values are required for the
76 .Bl -tag -width ".Va hint.owc.%d.atXXX"
81 .It Va hint.owc.%d.pins
82 This is a bitmask that defines a pin on the
84 that is to be used for the 1-Wire bus.
85 For instance, to configure pin 10, use the bitmask of 0x400.
86 Please note that this mask should have only one bit set
87 (any other bits - i.e., pins - will be ignored).
97 is a registered trademark of Maxim Integrated Products, Inc.
101 driver first appeared in
106 device driver and this manual page were written by
109 The gpio driver implements timing by busy waiting, which can cause a
110 high load on slower systems.
112 Overdrive mode has not actually been tested.