From 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Tue, 4 Aug 2015 12:17:53 -0700 Subject: Add the rt linux 4.1.3-rt3 as base Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang --- kernel/Documentation/hwmon/lm77 | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) create mode 100644 kernel/Documentation/hwmon/lm77 (limited to 'kernel/Documentation/hwmon/lm77') diff --git a/kernel/Documentation/hwmon/lm77 b/kernel/Documentation/hwmon/lm77 new file mode 100644 index 000000000..bfc915fe3 --- /dev/null +++ b/kernel/Documentation/hwmon/lm77 @@ -0,0 +1,38 @@ +Kernel driver lm77 +================== + +Supported chips: + * National Semiconductor LM77 + Prefix: 'lm77' + Addresses scanned: I2C 0x48 - 0x4b + Datasheet: Publicly available at the National Semiconductor website + http://www.national.com/ + +Author: Andras BALI + +Description +----------- + +The LM77 implements one temperature sensor. The temperature +sensor incorporates a band-gap type temperature sensor, +10-bit ADC, and a digital comparator with user-programmable upper +and lower limit values. + +The LM77 implements 3 limits: low (temp1_min), high (temp1_max) and +critical (temp1_crit.) It also implements an hysteresis mechanism which +applies to all 3 limits. The relative difference is stored in a single +register on the chip, which means that the relative difference between +the limit and its hysteresis is always the same for all 3 limits. + +This implementation detail implies the following: +* When setting a limit, its hysteresis will automatically follow, the + difference staying unchanged. For example, if the old critical limit + was 80 degrees C, and the hysteresis was 75 degrees C, and you change + the critical limit to 90 degrees C, then the hysteresis will + automatically change to 85 degrees C. +* All 3 hysteresis can't be set independently. We decided to make + temp1_crit_hyst writable, while temp1_min_hyst and temp1_max_hyst are + read-only. Setting temp1_crit_hyst writes the difference between + temp1_crit_hyst and temp1_crit into the chip, and the same relative + hysteresis applies automatically to the low and high limits. +* The limits should be set before the hysteresis. -- cgit 1.2.3-korg