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authorLinus Torvalds <torvalds@linux-foundation.org>2012-07-24 13:29:18 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-07-24 13:29:18 -0700
commit0cd5ff591ab6473355d5a6a47f7694def28e451d (patch)
treeaed0ea4fbb724f13208ed76d438518ffc9130a17 /Documentation
parent3539fc544f39017cf3403b9319fb4d74b5116135 (diff)
parente30bca12573fbf54e2470723aadc047549d147ce (diff)
Merge tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging
Pull hwmon updates from Guenter Roeck: "New drivers for DA9052/53 PMIC as well as HIH-6130/HIH-6131 humidity and temperature sensors. Convert drivers to use devm_ functions and to use dev_pm_ops. Address a couple of Coverity errors/warnings as well as compile warnings. Some functional improvements in applesmc driver." * tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging: (72 commits) hwmon: (applesmc) Ignore some temperature registers hwmon: (applesmc) Allow negative temperature values hwmon: (s3c-hwmon) Use devm_kzalloc instead of kzalloc hwmon: (w83781d) Fix compile warning hwmon: (applesmc) Shorten minimum wait time hwmon: (exynos4_tmu) Use struct dev_pm_ops for power management hwmon: (gpio-fan) Use struct dev_pm_ops for power management hwmon: (abituguru3) Use struct dev_pm_ops for power management hwmon: (abituguru) Use struct dev_pm_ops for power management hwmon: (acpi_power_meter) Fix unintentional integer overflow hwmon: (acpi_power_meter) Cleanup and optimizations hwmon: Honeywell Humidicon HIH-6130/HIH-6131 humidity and temperature sensor driver hwmon: (applesmc) Skip sensor mapping hwmon: (ntc_thermistor) Ensure that data->name string is terminated hwmon: (w83l785ts) Convert to use devm_ functions hwmon: (w83l785ts) Simplify code and improve readability hwmon: (smsc47m192) Convert to use devm_ functions hwmon: (smsc47m1) Convert to use devm_ functions hwmon: (smsc47b397) Convert to use devm_ functions hwmon: (k8temp) Convert to use devm_ functions ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/hwmon/da905261
-rw-r--r--Documentation/hwmon/hih613037
-rw-r--r--Documentation/hwmon/submitting-patches3
3 files changed, 101 insertions, 0 deletions
diff --git a/Documentation/hwmon/da9052 b/Documentation/hwmon/da9052
new file mode 100644
index 000000000000..ef898553638e
--- /dev/null
+++ b/Documentation/hwmon/da9052
@@ -0,0 +1,61 @@
+Supported chips:
+ * Dialog Semiconductors DA9052-BC and DA9053-AA/Bx PMICs
+ Prefix: 'da9052'
+ Datasheet: Datasheet is not publicly available.
+
+Authors: David Dajun Chen <dchen@diasemi.com>
+
+Description
+-----------
+
+The DA9052/53 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 10
+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: ICH - internal battery charger current measurement
+Channel 2: TBAT - output from the battery NTC
+Channel 3: VBAT - measurement of the battery voltage
+Channel 4: ADC_IN4 - high impedance input (0 - 2.5V)
+Channel 5: ADC_IN5 - high impedance input (0 - 2.5V)
+Channel 6: ADC_IN6 - high impedance input (0 - 2.5V)
+Channel 7: XY - TSI interface to measure the X and Y voltage of the touch
+ screen resistive potentiometers
+Channel 8: Internal Tjunc. - sense (internal temp. sensor)
+Channel 9: VBBAT - measurement of the backup battery voltage
+
+By using sysfs attributes we can measure the system voltage VDDOUT, the battery
+charging current ICH, battery temperature TBAT, battery junction temperature
+TJUNC, battery voltage VBAT and the back up battery voltage VBBAT.
+
+Voltage Monitoring
+------------------
+
+Voltages are sampled by a 10 bit ADC.
+
+The battery voltage is calculated as:
+ Milli volt = ((ADC value * 1000) / 512) + 2500
+
+The backup battery voltage is calculated as:
+ Milli volt = (ADC value * 2500) / 512;
+
+The voltages on ADC channels 4, 5 and 6 are calculated as:
+ Milli volt = (ADC value * 2500) / 1023
+
+Temperature Monitoring
+----------------------
+
+Temperatures are sampled by a 10 bit ADC. Junction and battery temperatures
+are monitored by the ADC channels.
+
+The junction temperature is calculated:
+ Degrees celsius = 1.708 * (TJUNC_RES - T_OFFSET) - 108.8
+The junction temperature attribute is supported by the driver.
+
+The battery temperature is calculated:
+ Degree Celcius = 1 / (t1 + 1/298)- 273
+where t1 = (1/B)* ln(( ADCval * 2.5)/(R25*ITBAT*255))
+Default values of R25, B, ITBAT are 10e3, 3380 and 50e-6 respectively.
diff --git a/Documentation/hwmon/hih6130 b/Documentation/hwmon/hih6130
new file mode 100644
index 000000000000..73dae918ea7b
--- /dev/null
+++ b/Documentation/hwmon/hih6130
@@ -0,0 +1,37 @@
+Kernel driver hih6130
+=====================
+
+Supported chips:
+ * Honeywell HIH-6130 / HIH-6131
+ Prefix: 'hih6130'
+ Addresses scanned: none
+ Datasheet: Publicly available at the Honeywell website
+ http://sensing.honeywell.com/index.php?ci_id=3106&la_id=1&defId=44872
+
+Author:
+ Iain Paton <ipaton0@gmail.com>
+
+Description
+-----------
+
+The HIH-6130 & HIH-6131 are humidity and temperature sensors in a SO8 package.
+The difference between the two devices is that the HIH-6131 has a condensation
+filter.
+
+The devices communicate with the I2C protocol. All sensors are set to the same
+I2C address 0x27 by default, so an entry with I2C_BOARD_INFO("hih6130", 0x27)
+can be used in the board setup code.
+
+Please see Documentation/i2c/instantiating-devices for details on how to
+instantiate I2C devices.
+
+sysfs-Interface
+---------------
+
+temp1_input - temperature input
+humidity1_input - humidity input
+
+Notes
+-----
+
+Command mode and alarms are not currently supported.
diff --git a/Documentation/hwmon/submitting-patches b/Documentation/hwmon/submitting-patches
index 86f42e8e9e49..790f774a3032 100644
--- a/Documentation/hwmon/submitting-patches
+++ b/Documentation/hwmon/submitting-patches
@@ -70,6 +70,9 @@ increase the chances of your change being accepted.
review more difficult. It may also result in code which is more complicated
than necessary. Use inline functions or just regular functions instead.
+* Use devres functions whenever possible to allocate resources. For rationale
+ and supported functions, please see Documentation/driver-model/devres.txt.
+
* If the driver has a detect function, make sure it is silent. Debug messages
and messages printed after a successful detection are acceptable, but it
must not print messages such as "Chip XXX not found/supported".