xref: /linux/Documentation/hwmon/raspberrypi-hwmon.rst (revision 079a028d6327e68cfa5d38b36123637b321c19a7)
1Kernel driver raspberrypi-hwmon
2===============================
3
4Supported boards:
5
6  * Raspberry Pi A+ (via GPIO on SoC)
7  * Raspberry Pi B+ (via GPIO on SoC)
8  * Raspberry Pi 2 B (via GPIO on SoC)
9  * Raspberry Pi 3 B (via GPIO on port expander)
10  * Raspberry Pi 3 B+ (via PMIC)
11
12Author: Stefan Wahren <stefan.wahren@i2se.com>
13
14Description
15-----------
16
17This driver periodically polls a mailbox property of the VC4 firmware to detect
18undervoltage conditions.
19
20Sysfs entries
21-------------
22
23======================= ======================================================
24in0_input		Core voltage in millivolts
25in1_input		SDRAM controller voltage in millivolts
26in2_input		SDRAM I/O voltage in millivolts
27in3_input		SDRAM PHY voltage in millivolts
28in0_label		"core"
29in1_label		"sdram_c"
30in2_label		"sdram_i"
31in3_label		"sdram_p"
32in0_lcrit_alarm		Undervoltage alarm
33======================= ======================================================
34
35The voltage inputs and labels are only exposed if the firmware reports support
36for the corresponding voltage ID.
37