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authorTakashi Iwai <tiwai@suse.de>2014-09-03 16:57:41 +0200
committerTakashi Iwai <tiwai@suse.de>2014-09-03 16:57:41 +0200
commit05244d166739ae273fdc7a2151bdef61df49ca7d (patch)
tree9065482d33f445c90f0b99d29aa51485d1d96488 /Documentation/w1
parentacf08081adb5e8fe0519eb97bb49797ef52614d6 (diff)
parentf58f0cba15c2d0bfbc72b1eedd0a6294e8c83419 (diff)
downloadlinux-05244d166739ae273fdc7a2151bdef61df49ca7d.tar.gz
Merge tag 'asoc-v3.17-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Fixes for v3.17 A few more driver specific fixes on top of the currently pending fixes (which are already in your tree but not Linus').
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+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.