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authorLinus Torvalds <torvalds@linux-foundation.org>2019-05-06 19:56:51 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-05-06 19:56:51 -0700
commit7aefd944f038c7469571adb37769cb6f3924ecfa (patch)
treef0a8dc23633b6bbbc4f0bff932f332e847fb6c1b /Documentation/hwmon/g760a.rst
parentMerge branch 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip (diff)
parenthwmon: (lm75) Add support for TMP75B (diff)
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Merge tag 'hwmon-for-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging
Pull hwmon updates from Guenter Roeck: - Add driver for Intersil ISL68137 PWM Controller - Add driver for Lochnagar 2 - Add driver for Infineon IR38064 Voltage Regulator - Add support for TMP75B to lm75 driver - Convert documentation to ReST format - Use request_muxed_region for Super-IO accesses in several drivers - Add 'samples' attribute to ABI, and start using it - Add support for custom sysfs attributes to pmbus drivers (used in ISL68137 driver) - Introduce HWMON_CHANNEL_INFO macro - Automated changes: - Use permission specific [SENSOR_][DEVICE_]ATTR variants - Fix build warnings due to unused of_device_id structures - Use HWMON_CHANNEL_INFO macro - Various minor improvements and fixes * tag 'hwmon-for-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging: (125 commits) hwmon: (lm75) Add support for TMP75B dt-bindings: hwmon: Add tmp75b to lm75.txt hwmon: (s3c) Use dev_get_drvdata() hwmon: (max6650) Drop call to thermal_cdev_update docs: hwmon: remove the extension from .rst files docs: hwmon: convert three docs to ReST format hwmon: (max6650) add thermal cooling device capability hwmon: (ina3221) Add voltage conversion time settings hwmon: (ina3221) Do not read-back to cache reg_config docs: hwmon: Add an index file and rename docs to *.rst docs: hwmon: convert remaining files to ReST format docs: hwmon: misc files: convert to ReST format docs: hwmon: pmbus files: convert to ReST format docs: hwmon: k8temp, w83793: convert to ReST format docs: hwmon: da9052, da9055: convert to ReST format docs: hwmon: wm831x, wm8350: convert to ReST format docs: hwmon: dme1737, vt1211: convert to ReST format docs: hwmon: ads1015: convert to ReST format docs: hwmon: asc7621: convert to ReST format docs: hwmon: ibmpowernv: convert to ReST format ...
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+Kernel driver g760a
+===================
+
+Supported chips:
+
+ * Global Mixed-mode Technology Inc. G760A
+
+ Prefix: 'g760a'
+
+ Datasheet: Publicly available at the GMT website
+
+ http://www.gmt.com.tw/product/datasheet/EDS-760A.pdf
+
+Author: Herbert Valerio Riedel <hvr@gnu.org>
+
+Description
+-----------
+
+The GMT G760A Fan Speed PWM Controller is connected directly to a fan
+and performs closed-loop control of the fan speed.
+
+The fan speed is programmed by setting the period via 'pwm1' of two
+consecutive speed pulses. The period is defined in terms of clock
+cycle counts of an assumed 32kHz clock source.
+
+Setting a period of 0 stops the fan; setting the period to 255 sets
+fan to maximum speed.
+
+The measured fan rotation speed returned via 'fan1_input' is derived
+from the measured speed pulse period by assuming again a 32kHz clock
+source and a 2 pulse-per-revolution fan.
+
+The 'alarms' file provides access to the two alarm bits provided by
+the G760A chip's status register: Bit 0 is set when the actual fan
+speed differs more than 20% with respect to the programmed fan speed;
+bit 1 is set when fan speed is below 1920 RPM.
+
+The g760a driver will not update its values more frequently than every
+other second; reading them more often will do no harm, but will return
+'old' values.