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diff --git a/Documentation/w1/slaves/w1_ds2406.rst b/Documentation/w1/slaves/w1_ds2406.rst new file mode 100644 index 000000000000..d3e68266084f --- /dev/null +++ b/Documentation/w1/slaves/w1_ds2406.rst @@ -0,0 +1,27 @@ +======================= +w1_ds2406 kernel driver +======================= + +Supported chips: + + * Maxim DS2406 (and other family 0x12) addressable switches + +Author: Scott Alfter <scott@alfter.us> + +Description +----------- + +The w1_ds2406 driver allows connected devices to be switched on and off. +These chips also provide 128 bytes of OTP EPROM, but reading/writing it is +not supported. In TSOC-6 form, the DS2406 provides two switch outputs and +can be provided with power on a dedicated input. In TO-92 form, it provides +one output and uses parasitic power only. + +The driver provides two sysfs files. state is readable; it gives the +current state of each switch, with PIO A in bit 0 and PIO B in bit 1. The +driver ORs this state with 0x30, so shell scripts get an ASCII 0/1/2/3 to +work with. output is writable; bits 0 and 1 control PIO A and B, +respectively. Bits 2-7 are ignored, so it's safe to write ASCII data. + +CRCs are checked on read and write. Failed checks cause an I/O error to be +returned. On a failed write, the switch status is not changed. |