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authorMauro Carvalho Chehab <mchehab+samsung@kernel.org>2019-04-17 06:46:29 -0300
committerGuenter Roeck <linux@roeck-us.net>2019-04-17 10:37:23 -0700
commit7ebd8b66dd9e5a0b65e5ee5e2b8e7ca382ec97b7 (patch)
tree9db30159bd32bec125c7d49e80a79bb7c4da0c8e /Documentation/hwmon/da9055.rst
parentb04f2f7d387b3160883c2a1f5e2285483a791e82 (diff)
docs: hwmon: Add an index file and rename docs to *.rst
Now that all files were converted to ReST format, rename them and add an index. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
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+Kernel driver da9055
+====================
+
+Supported chips:
+ * Dialog Semiconductors DA9055 PMIC
+
+ Prefix: 'da9055'
+
+ Datasheet: Datasheet is not publicly available.
+
+Authors: David Dajun Chen <dchen@diasemi.com>
+
+Description
+-----------
+
+The DA9055 provides an Analogue to Digital Converter (ADC) with 10 bits
+resolution and track and hold circuitry combined with an analogue input
+multiplexer. The analogue input multiplexer will allow conversion of up to 5
+different inputs. The track and hold circuit ensures stable input voltages at
+the input of the ADC during the conversion.
+
+The ADC is used to measure the following inputs:
+
+- Channel 0: VDDOUT - measurement of the system voltage
+- Channel 1: ADC_IN1 - high impedance input (0 - 2.5V)
+- Channel 2: ADC_IN2 - high impedance input (0 - 2.5V)
+- Channel 3: ADC_IN3 - high impedance input (0 - 2.5V)
+- Channel 4: Internal Tjunc. - sense (internal temp. sensor)
+
+By using sysfs attributes we can measure the system voltage VDDOUT,
+chip junction temperature and auxiliary channels voltages.
+
+Voltage Monitoring
+------------------
+
+Voltages are sampled in a AUTO mode it can be manually sampled too and results
+are stored in a 10 bit ADC.
+
+The system voltage is calculated as:
+
+ Milli volt = ((ADC value * 1000) / 85) + 2500
+
+The voltages on ADC channels 1, 2 and 3 are calculated as:
+
+ Milli volt = (ADC value * 1000) / 102
+
+Temperature Monitoring
+----------------------
+
+Temperatures are sampled by a 10 bit ADC. Junction temperatures
+are monitored by the ADC channels.
+
+The junction temperature is calculated:
+
+ Degrees celsius = -0.4084 * (ADC_RES - T_OFFSET) + 307.6332
+
+The junction temperature attribute is supported by the driver.