diff options
Diffstat (limited to 'Documentation/hwmon')
| -rw-r--r-- | Documentation/hwmon/emc1403 | 59 | ||||
| -rw-r--r-- | Documentation/hwmon/hwmon-kernel-api.txt | 107 | ||||
| -rw-r--r-- | Documentation/hwmon/jc42 | 16 | ||||
| -rw-r--r-- | Documentation/hwmon/lm77 | 20 | ||||
| -rw-r--r-- | Documentation/hwmon/nct6683 | 57 |
5 files changed, 251 insertions, 8 deletions
diff --git a/Documentation/hwmon/emc1403 b/Documentation/hwmon/emc1403 new file mode 100644 index 00000000000..a869b0ef6a9 --- /dev/null +++ b/Documentation/hwmon/emc1403 @@ -0,0 +1,59 @@ +Kernel driver emc1403 +===================== + +Supported chips: + * SMSC / Microchip EMC1402, EMC1412 + Addresses scanned: I2C 0x18, 0x1c, 0x29, 0x4c, 0x4d, 0x5c + Prefix: 'emc1402' + Datasheets: + http://ww1.microchip.com/downloads/en/DeviceDoc/1412.pdf + http://ww1.microchip.com/downloads/en/DeviceDoc/1402.pdf + * SMSC / Microchip EMC1403, EMC1404, EMC1413, EMC1414 + Addresses scanned: I2C 0x18, 0x29, 0x4c, 0x4d + Prefix: 'emc1403', 'emc1404' + Datasheets: + http://ww1.microchip.com/downloads/en/DeviceDoc/1403_1404.pdf + http://ww1.microchip.com/downloads/en/DeviceDoc/1413_1414.pdf + * SMSC / Microchip EMC1422 + Addresses scanned: I2C 0x4c + Prefix: 'emc1422' + Datasheet: + http://ww1.microchip.com/downloads/en/DeviceDoc/1422.pdf + * SMSC / Microchip EMC1423, EMC1424 + Addresses scanned: I2C 0x4c + Prefix: 'emc1423', 'emc1424' + Datasheet: + http://ww1.microchip.com/downloads/en/DeviceDoc/1423_1424.pdf + +Author: + Kalhan Trisal <kalhan.trisal@intel.com + + +Description +----------- + +The Standard Microsystems Corporation (SMSC) / Microchip EMC14xx chips +contain up to four temperature sensors. EMC14x2 support two sensors +(one internal, one external). EMC14x3 support three sensors (one internal, +two external), and EMC14x4 support four sensors (one internal, three +external). + +The chips implement three limits for each sensor: low (tempX_min), high +(tempX_max) and critical (tempX_crit.) The chips also implement an +hysteresis mechanism which applies to all 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 three 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. +* The hysteresis values can't be set independently. We decided to make + only temp1_crit_hyst writable, while all other hysteresis attributes + 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 all other limits. +* The limits should be set before the hysteresis. diff --git a/Documentation/hwmon/hwmon-kernel-api.txt b/Documentation/hwmon/hwmon-kernel-api.txt new file mode 100644 index 00000000000..2ecdbfc85ec --- /dev/null +++ b/Documentation/hwmon/hwmon-kernel-api.txt @@ -0,0 +1,107 @@ +The Linux Hardware Monitoring kernel API. +========================================= + +Guenter Roeck + +Introduction +------------ + +This document describes the API that can be used by hardware monitoring +drivers that want to use the hardware monitoring framework. + +This document does not describe what a hardware monitoring (hwmon) Driver or +Device is. It also does not describe the API which can be used by user space +to communicate with a hardware monitoring device. If you want to know this +then please read the following file: Documentation/hwmon/sysfs-interface. + +For additional guidelines on how to write and improve hwmon drivers, please +also read Documentation/hwmon/submitting-patches. + +The API +------- +Each hardware monitoring driver must #include <linux/hwmon.h> and, in most +cases, <linux/hwmon-sysfs.h>. linux/hwmon.h declares the following +register/unregister functions: + +struct device *hwmon_device_register(struct device *dev); +struct device * +hwmon_device_register_with_groups(struct device *dev, const char *name, + void *drvdata, + const struct attribute_group **groups); + +struct device * +devm_hwmon_device_register_with_groups(struct device *dev, + const char *name, void *drvdata, + const struct attribute_group **groups); + +void hwmon_device_unregister(struct device *dev); +void devm_hwmon_device_unregister(struct device *dev); + +hwmon_device_register registers a hardware monitoring device. The parameter +of this function is a pointer to the parent device. +This function returns a pointer to the newly created hardware monitoring device +or PTR_ERR for failure. If this registration function is used, hardware +monitoring sysfs attributes are expected to have been created and attached to +the parent device prior to calling hwmon_device_register. A name attribute must +have been created by the caller. + +hwmon_device_register_with_groups is similar to hwmon_device_register. However, +it has additional parameters. The name parameter is a pointer to the hwmon +device name. The registration function wil create a name sysfs attribute +pointing to this name. The drvdata parameter is the pointer to the local +driver data. hwmon_device_register_with_groups will attach this pointer +to the newly allocated hwmon device. The pointer can be retrieved by the driver +using dev_get_drvdata() on the hwmon device pointer. The groups parameter is +a pointer to a list of sysfs attribute groups. The list must be NULL terminated. +hwmon_device_register_with_groups creates the hwmon device with name attribute +as well as all sysfs attributes attached to the hwmon device. + +devm_hwmon_device_register_with_groups is similar to +hwmon_device_register_with_groups. However, it is device managed, meaning the +hwmon device does not have to be removed explicitly by the removal function. + +hwmon_device_unregister deregisters a registered hardware monitoring device. +The parameter of this function is the pointer to the registered hardware +monitoring device structure. This function must be called from the driver +remove function if the hardware monitoring device was registered with +hwmon_device_register or with hwmon_device_register_with_groups. + +devm_hwmon_device_unregister does not normally have to be called. It is only +needed for error handling, and only needed if the driver probe fails after +the call to devm_hwmon_device_register_with_groups. + +The header file linux/hwmon-sysfs.h provides a number of useful macros to +declare and use hardware monitoring sysfs attributes. + +In many cases, you can use the exsting define DEVICE_ATTR to declare such +attributes. This is feasible if an attribute has no additional context. However, +in many cases there will be additional information such as a sensor index which +will need to be passed to the sysfs attribute handling function. + +SENSOR_DEVICE_ATTR and SENSOR_DEVICE_ATTR_2 can be used to define attributes +which need such additional context information. SENSOR_DEVICE_ATTR requires +one additional argument, SENSOR_DEVICE_ATTR_2 requires two. + +SENSOR_DEVICE_ATTR defines a struct sensor_device_attribute variable. +This structure has the following fields. + +struct sensor_device_attribute { + struct device_attribute dev_attr; + int index; +}; + +You can use to_sensor_dev_attr to get the pointer to this structure from the +attribute read or write function. Its parameter is the device to which the +attribute is attached. + +SENSOR_DEVICE_ATTR_2 defines a struct sensor_device_attribute_2 variable, +which is defined as follows. + +struct sensor_device_attribute_2 { + struct device_attribute dev_attr; + u8 index; + u8 nr; +}; + +Use to_sensor_dev_attr_2 to get the pointer to this structure. Its parameter +is the device to which the attribute is attached. diff --git a/Documentation/hwmon/jc42 b/Documentation/hwmon/jc42 index 868d74d6b77..f3893f7440d 100644 --- a/Documentation/hwmon/jc42 +++ b/Documentation/hwmon/jc42 @@ -5,9 +5,12 @@ Supported chips: * Analog Devices ADT7408 Datasheets: http://www.analog.com/static/imported-files/data_sheets/ADT7408.pdf - * Atmel AT30TS00 + * Atmel AT30TS00, AT30TS002A/B, AT30TSE004A Datasheets: http://www.atmel.com/Images/doc8585.pdf + http://www.atmel.com/Images/doc8711.pdf + http://www.atmel.com/Images/Atmel-8852-SEEPROM-AT30TSE002A-Datasheet.pdf + http://www.atmel.com/Images/Atmel-8868-DTS-AT30TSE004A-Datasheet.pdf * IDT TSE2002B3, TSE2002GB2, TS3000B3, TS3000GB2 Datasheets: http://www.idt.com/sites/default/files/documents/IDT_TSE2002B3C_DST_20100512_120303152056.pdf @@ -34,12 +37,13 @@ Supported chips: Datasheet: http://www.onsemi.com/pub_link/Collateral/CAT34TS02-D.PDF http://www.onsemi.com/pub/Collateral/CAT6095-D.PDF - * ST Microelectronics STTS424, STTS424E02, STTS2002, STTS3000 + * ST Microelectronics STTS424, STTS424E02, STTS2002, STTS2004, STTS3000 Datasheets: - http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00157556.pdf - http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00157558.pdf - http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00225278.pdf - http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATA_BRIEF/CD00270920.pdf + http://www.st.com/web/en/resource/technical/document/datasheet/CD00157556.pdf + http://www.st.com/web/en/resource/technical/document/datasheet/CD00157558.pdf + http://www.st.com/web/en/resource/technical/document/datasheet/CD00266638.pdf + http://www.st.com/web/en/resource/technical/document/datasheet/CD00225278.pdf + http://www.st.com/web/en/resource/technical/document/datasheet/DM00076709.pdf * JEDEC JC 42.4 compliant temperature sensor chips Datasheet: http://www.jedec.org/sites/default/files/docs/4_01_04R19.pdf diff --git a/Documentation/hwmon/lm77 b/Documentation/hwmon/lm77 index 57c3a46d637..bfc915fe363 100644 --- a/Documentation/hwmon/lm77 +++ b/Documentation/hwmon/lm77 @@ -18,5 +18,21 @@ sensor incorporates a band-gap type temperature sensor, 10-bit ADC, and a digital comparator with user-programmable upper and lower limit values. -Limits can be set through the Overtemperature Shutdown register and -Hysteresis register. +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. diff --git a/Documentation/hwmon/nct6683 b/Documentation/hwmon/nct6683 new file mode 100644 index 00000000000..c1301d4300c --- /dev/null +++ b/Documentation/hwmon/nct6683 @@ -0,0 +1,57 @@ +Kernel driver nct6683 +===================== + +Supported chips: + * Nuvoton NCT6683D + Prefix: 'nct6683' + Addresses scanned: ISA address retrieved from Super I/O registers + Datasheet: Available from Nuvoton upon request + +Authors: + Guenter Roeck <linux@roeck-us.net> + +Description +----------- + +This driver implements support for the Nuvoton NCT6683D eSIO chip. + +The chips implement up to shared 32 temperature and voltage sensors. +It supports up to 16 fan rotation sensors and up to 8 fan control engines. + +Temperatures are measured in degrees Celsius. Measurement resolution is +0.5 degrees C. + +Voltage sensors (also known as IN sensors) report their values in millivolts. + +Fan rotation speeds are reported in RPM (rotations per minute). + +Usage Note +---------- + +Limit register locations on Intel boards with EC firmware version 1.0 +build date 04/03/13 do not match the register locations in the Nuvoton +datasheet. Nuvoton confirms that Intel uses a special firmware version +with different register addresses. The specification describing the Intel +firmware is held under NDA by Nuvoton and Intel and not available +to the public. + +Some of the register locations can be reverse engineered; others are too +well hidden. Given this, writing any values from the operating system is +considered too risky with this firmware and has been disabled. All limits +must all be written from the BIOS. + +The driver has only been tested with the Intel firmware, and by default +only instantiates on Intel boards. To enable it on non-Intel boards, +set the 'force' module parameter to 1. + +Tested Boards and Firmware Versions +----------------------------------- + +The driver has been reported to work with the following boards and +firmware versions. + +Board Firmware version +--------------------------------------------------------------- +Intel DH87RL NCT6683D EC firmware version 1.0 build 04/03/13 +Intel DH87MC NCT6683D EC firmware version 1.0 build 04/03/13 +Intel DB85FL NCT6683D EC firmware version 1.0 build 04/03/13 |