Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 111 insertions, 0 deletions

diff --git a/Documentation/hwmon/ntc_thermistor.rst b/Documentation/hwmon/ntc_thermistor.rst
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+Kernel driver ntc_thermistor
+============================
+
+Supported thermistors from Murata:
+
+* Murata NTC Thermistors NCP15WB473, NCP18WB473, NCP21WB473, NCP03WB473,
+  NCP15WL333, NCP03WF104, NCP15XH103
+
+  Prefixes: 'ncp15wb473', 'ncp18wb473', 'ncp21wb473', 'ncp03wb473',
+  'ncp15wl333', 'ncp03wf104', 'ncp15xh103'
+
+  Datasheet: Publicly available at Murata
+
+Supported thermistors from EPCOS:
+
+* EPCOS NTC Thermistors B57330V2103
+
+  Prefixes: b57330v2103
+
+  Datasheet: Publicly available at EPCOS
+
+Other NTC thermistors can be supported simply by adding compensation
+tables; e.g., NCP15WL333 support is added by the table ncpXXwl333.
+
+Authors:
+
+	MyungJoo Ham <myungjoo.ham@samsung.com>
+
+Description
+-----------
+
+The NTC (Negative Temperature Coefficient) thermistor is a simple thermistor
+that requires users to provide the resistance and lookup the corresponding
+compensation table to get the temperature input.
+
+The NTC driver provides lookup tables with a linear approximation function
+and four circuit models with an option not to use any of the four models.
+
+Using the following convention::
+
+   $	resistor
+   [TH]	the thermistor
+
+The four circuit models provided are:
+
+1. connect = NTC_CONNECTED_POSITIVE, pullup_ohm > 0::
+
+     [pullup_uV]
+	 |    |
+	[TH]  $ (pullup_ohm)
+	 |    |
+	 +----+-----------------------[read_uV]
+	 |
+	 $ (pulldown_ohm)
+	 |
+	-+- (ground)
+
+2. connect = NTC_CONNECTED_POSITIVE, pullup_ohm = 0 (not-connected)::
+
+     [pullup_uV]
+	 |
+	[TH]
+	 |
+	 +----------------------------[read_uV]
+	 |
+	 $ (pulldown_ohm)
+	 |
+	-+- (ground)
+
+3. connect = NTC_CONNECTED_GROUND, pulldown_ohm > 0::
+
+     [pullup_uV]
+	 |
+	 $ (pullup_ohm)
+	 |
+	 +----+-----------------------[read_uV]
+	 |    |
+	[TH]  $ (pulldown_ohm)
+	 |    |
+	-+----+- (ground)
+
+4. connect = NTC_CONNECTED_GROUND, pulldown_ohm = 0 (not-connected)::
+
+     [pullup_uV]
+	 |
+	 $ (pullup_ohm)
+	 |
+	 +----------------------------[read_uV]
+	 |
+	[TH]
+	 |
+	-+- (ground)
+
+When one of the four circuit models is used, read_uV, pullup_uV, pullup_ohm,
+pulldown_ohm, and connect should be provided. When none of the four models
+are suitable or the user can get the resistance directly, the user should
+provide read_ohm and _not_ provide the others.
+
+Sysfs Interface
+---------------
+
+=============== == =============================================================
+name		   the mandatory global attribute, the thermistor name.
+=============== == =============================================================
+temp1_type	RO always 4 (thermistor)
+
+temp1_input	RO measure the temperature and provide the measured value.
+		   (reading this file initiates the reading procedure.)
+=============== == =============================================================
+
+Note that each NTC thermistor has only _one_ thermistor; thus, only temp1 exists.