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+What: /sys/bus/w1/devices/.../alarms
+Date: May 2020
+Contact: Akira Shimahara <akira215corp@gmail.com>
+Description:
+ (RW) read or write TH and TL (Temperature High an Low) alarms.
+ Values shall be space separated and in the device range
+ (typical -55 degC to 125 degC), if not values will be trimmed
+ to device min/max capabilities. Values are integer as they are
+ stored in a 8bit register in the device. Lowest value is
+ automatically put to TL. Once set, alarms could be search at
+ master level, refer to Documentation/w1/w1-generic.rst for
+ detailed information
+Users: any user space application which wants to communicate with
+ w1_term device
+
+
+What: /sys/bus/w1/devices/.../eeprom
+Date: May 2020
+Contact: Akira Shimahara <akira215corp@gmail.com>
+Description:
+ (WO) writing that file will either trigger a save of the
+ device data to its embedded EEPROM, either restore data
+ embedded in device EEPROM. Be aware that devices support
+ limited EEPROM writing cycles (typical 50k)
+
+ * 'save': save device RAM to EEPROM
+ * 'restore': restore EEPROM data in device RAM
+
+Users: any user space application which wants to communicate with
+ w1_term device
+
+
+What: /sys/bus/w1/devices/.../ext_power
+Date: May 2020
+Contact: Akira Shimahara <akira215corp@gmail.com>
+Description:
+ (RO) return the power status by asking the device
+
+ * '0': device parasite powered
+ * '1': device externally powered
+ * '-xx': xx is kernel error when reading power status
+
+Users: any user space application which wants to communicate with
+ w1_term device
+
+
+What: /sys/bus/w1/devices/.../resolution
+Date: May 2020
+Contact: Akira Shimahara <akira215corp@gmail.com>
+Description:
+ (RW) get or set the device resolution (on supported devices,
+ if not, this entry is not present). Note that the resolution
+ will be changed only in device RAM, so it will be cleared when
+ power is lost. Trigger a 'save' to EEPROM command to keep
+ values after power-on. Read or write are :
+
+ * '9..14': device resolution in bit
+ or resolution to set in bit
+ * '-xx': xx is kernel error when reading the resolution
+ * Anything else: do nothing
+
+ Some DS18B20 clones are fixed in 12-bit resolution, so the
+ actual resolution is read back from the chip and verified. Error
+ is reported if the results differ.
+Users: any user space application which wants to communicate with
+ w1_term device
+
+
+What: /sys/bus/w1/devices/.../temperature
+Date: May 2020
+Contact: Akira Shimahara <akira215corp@gmail.com>
+Description:
+ (RO) return the temperature in 1/1000 degC.
+
+ * If a bulk read has been triggered, it will directly
+ return the temperature computed when the bulk read
+ occurred, if available. If not yet available, nothing
+ is returned (a debug kernel message is sent), you
+ should retry later on.
+ * If no bulk read has been triggered, it will trigger
+ a conversion and send the result. Note that the
+ conversion duration depend on the resolution (if
+ device support this feature). It takes 94ms in 9bits
+ resolution, 750ms for 12bits.
+
+Users: any user space application which wants to communicate with
+ w1_term device
+
+
+What: /sys/bus/w1/devices/.../w1_slave
+Date: May 2020
+Contact: Akira Shimahara <akira215corp@gmail.com>
+Description:
+ (RW) return the temperature in 1/1000 degC.
+ *read*: return 2 lines with the hexa output data sent on the
+ bus, return the CRC check and temperature in 1/1000 degC
+ *write*:
+
+ * '0' : save the 2 or 3 bytes to the device EEPROM
+ (i.e. TH, TL and config register)
+ * '9..14' : set the device resolution in RAM
+ (if supported)
+ * Anything else: do nothing
+
+ refer to Documentation/w1/slaves/w1_therm.rst for detailed
+ information.
+Users: any user space application which wants to communicate with
+ w1_term device
+
+
+What: /sys/bus/w1/devices/w1_bus_masterXX/therm_bulk_read
+Date: May 2020
+Contact: Akira Shimahara <akira215corp@gmail.com>
+Description:
+ (RW) trigger a bulk read conversion. read the status
+
+ *read*:
+ * '-1':
+ conversion in progress on at least 1 sensor
+ * '1' :
+ conversion complete but at least one sensor
+ value has not been read yet
+ * '0' :
+ no bulk operation. Reading temperature will
+ trigger a conversion on each device
+
+ *write*:
+ 'trigger': trigger a bulk read on all supporting
+ devices on the bus
+
+ Note that if a bulk read is sent but one sensor is not read
+ immediately, the next access to temperature on this device
+ will return the temperature measured at the time of issue
+ of the bulk read command (not the current temperature).
+Users: any user space application which wants to communicate with
+ w1_term device
+
+
+What: /sys/bus/w1/devices/.../conv_time
+Date: July 2020
+Contact: Ivan Zaentsev <ivan.zaentsev@wirenboard.ru>
+Description:
+ (RW) Get, set, or measure a temperature conversion time. The
+ setting remains active until a resolution change. Then it is
+ reset to default (datasheet) conversion time for a new
+ resolution.
+
+ *read*:
+ Actual conversion time in milliseconds.
+
+ *write*:
+ * '0':
+ Set the default conversion time from the datasheet.
+ * '1':
+ Measure and set the conversion time. Make a single
+ temperature conversion, measure an actual value.
+ Increase it by 20% for temperature range. A new
+ conversion time can be obtained by reading this
+ same attribute.
+ * other positive value:
+ Set the conversion time in milliseconds.
+
+Users: An application using the w1_term device
+
+
+What: /sys/bus/w1/devices/.../features
+Date: July 2020
+Contact: Ivan Zaentsev <ivan.zaentsev@wirenboard.ru>
+Description:
+ (RW) Control optional driver settings.
+ Bit masks to read/write (bitwise OR):
+
+ == ============================================================
+ 1 Enable check for conversion success. If byte 6 of
+ scratchpad memory is 0xC after conversion, and
+ temperature reads 85.00 (powerup value) or 127.94
+ (insufficient power) - return a conversion error.
+
+ 2 Enable poll for conversion completion. Generate read cycles
+ after the conversion start and wait for 1's. In parasite
+ power mode this feature is not available.
+ == ============================================================
+
+ *read*:
+ Currently selected features.
+
+ *write*:
+ Select features.
+
+Users: An application using the w1_term device