LINUX-I2C: Difference between revisions
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# ls /sys/class/i2c-dev/ | # ls /sys/class/i2c-dev/ | ||
i2c-0 i2c-1 i2c-2 i2c-3 | i2c-0 i2c-1 i2c-2 i2c-3 | ||
</pre> | |||
| DART-MX95= | |||
==List of available I2C buses on DART-MX95== | |||
<pre> | |||
# ls -l /dev/i2c-* | |||
crw------- 1 root root 89, 2 Sep 20 2023 /dev/i2c-2 | |||
crw------- 1 root root 89, 7 Sep 20 2023 /dev/i2c-7 | |||
</pre> | |||
System class on DART-MX95: | |||
<pre> | |||
# ls /sys/class/i2c-dev/ | |||
i2c-2 i2c-7 | |||
</pre> | </pre> | ||
}} | }} | ||
Revision as of 18:38, 15 July 2024
Warning: This page is designed to be used with a 'release' URL parameter.
This page is using the default release mx8mm-yocto-kirkstone-5.15-2.0.x-v1.0.
To view this page for a specific Variscite SoM and software release, please follow these steps:
- Visit variwiki.com
- Select your SoM
- Select the software release
DART-MX8M-MINI I2C
Available I2C buses
List of available I2C buses:
# ls -l /dev/i2c-* crw------- 1 root root 89, 0 Jul 4 09:09 /dev/i2c-0 crw------- 1 root root 89, 1 Jul 4 09:09 /dev/i2c-1 crw------- 1 root root 89, 2 Jul 4 09:09 /dev/i2c-2 crw------- 1 root root 89, 3 Jul 4 09:09 /dev/i2c-3
System class:
# ls /sys/class/i2c-dev/ i2c-0 i2c-1 i2c-2 i2c-3
I2C devices per bus
Scan bus 0:
# i2cdetect -y -r 0
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- UU -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- UU -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- UU -- -- -- --
50: -- -- 52 53 -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --
Scan bus 1:
# i2cdetect -y -r 1
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- UU 3d -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: -- -- -- -- 54 55 -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- UU -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --
Scan bus 2:
# i2cdetect -y -r 2
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --
Scan bus 3:
# i2cdetect -y -r 3
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --
When the device is marked with "UU" it means that a driver is using it.
When the device is marked with numbers it means that no driver is using it.
Reading / Writing from an I2C device
Variscite includes I2CTools as a part of the default file system build, examples of optional commands:
i2cdump - dump the content of an I2C device
i2cset - write a single character to an I2C device
i2cget - read a single character to an I2C device
In addition follow 'C' code example as describe in the linux kernel documentation : https://www.kernel.org/doc/Documentation/i2c/dev-interface
Variscite's system integrated I2C devices
Note: Do not write to Variscite's on-SOM EEPROM or you will damage the SOM!
Variscite devices on DART-MX8M-MINI:
I2C-0 0x2c - MIPI-LVDS bridge on SOM I2C-0 0x4b – PMIC on SOM I2C-0 0x52 - EEPROM on SOM. Don't modify! I2C-0 0x53 - EEPROM on SOM. Don't modify! I2C-1 0x38 – Capacitive touch controller on kit display I2C-1 0x3c – MIPI-CSI camera on expansion board I2C-1 0x3d – USB Type C controller on carrier board I2C-1 0x54 - EEPROM on carrier board I2C-1 0x55 - EEPROM on carrier board I2C-1 0x68 – RTC on carrier board I2C-2 0x1a - Audio codec on SOM I2C-3 0x20 - TCA6408 GPIO expander on carrier board V2 only I2C-3 0x21 - TCA6408 GPIO expander on carrier board V2 only
Variscite devices on VAR-SOM-MX8M-MINI:
I2C-0 0x2c - MIPI-LVDS bridge on SOM I2C-0 0x4b – PMIC on SOM I2C-0 0x52 - EEPROM on SOM. Don't modify! I2C-0 0x53 - EEPROM on SOM. Don't modify! I2C-1 0x20 - PCA9534 GPIO expander on carrier board I2C-1 0x3c – MIPI-CSI camera on expansion board I2C-1 0x3d – USB Type C controller on carrier board I2C-2 0x1a - Audio codec on SOM I2C-2 0x38 – Capacitive touch controller on kit display I2C-2 0x54 - EEPROM on carrier board I2C-2 0x55 - EEPROM on carrier board I2C-2 0x68 – RTC on carrier board