xref: /linux/Documentation/hwmon/lattepanda-sigma-ec.rst (revision 7a0e692a0381254b2f77c54dec100cd3325a6fdf)
1.. SPDX-License-Identifier: GPL-2.0-or-later
2
3Kernel driver lattepanda-sigma-ec
4=================================
5
6Supported systems:
7
8  * LattePanda Sigma (Intel 13th Gen i5-1340P)
9
10    DMI vendor: LattePanda
11
12    DMI product: LattePanda Sigma
13
14    BIOS version: 5.27 (verified)
15
16    Datasheet: Not available (EC registers discovered empirically)
17
18Author: Mariano Abad <weimaraner@gmail.com>
19
20Description
21-----------
22
23This driver provides hardware monitoring for the LattePanda Sigma
24single-board computer made by DFRobot. The board uses an ITE IT8613E
25Embedded Controller to manage a CPU cooling fan and thermal sensors.
26
27The BIOS declares the ACPI Embedded Controller (``PNP0C09``) with
28``_STA`` returning 0, preventing the kernel's ACPI EC subsystem from
29initializing. This driver reads the EC directly via the standard ACPI
30EC I/O ports (``0x62`` data, ``0x66`` command/status).
31
32Sysfs attributes
33----------------
34
35======================= ===============================================
36``fan1_input``          Fan speed in RPM (EC registers 0x2E:0x2F,
37                        16-bit big-endian)
38``fan1_label``          "CPU Fan"
39``temp1_input``         Board/ambient temperature in millidegrees
40                        Celsius (EC register 0x60, unsigned)
41``temp1_label``         "Board Temp"
42``temp2_input``         CPU proximity temperature in millidegrees
43                        Celsius (EC register 0x70, unsigned)
44``temp2_label``         "CPU Temp"
45======================= ===============================================
46
47Module parameters
48-----------------
49
50``force`` (bool, default false)
51    Force loading on BIOS versions other than 5.27. The driver still
52    requires DMI vendor and product name matching.
53
54Known limitations
55-----------------
56
57* Fan speed control is not supported. The fan is always under EC
58  automatic control.
59* The EC register map was verified only on BIOS version 5.27.
60  Other versions may use different register offsets; use the ``force``
61  parameter at your own risk.
62