PHYTEC
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&i2c1 {
[...]
rv3028: rv3028@52 {
compatible = "microcrystal,rv3028";
reg = <0x52>;
trickle-resistor-ohms = <1000>; /* maps to 3 kOhm setting */
enable-level-switching-mode;
clocks = <&rtcclkout>;
clock-output-names = "rv3028-clkout";
status = "okay";
};
[...]
};
Watchdog
The PHYTEC i.MX8MP modules include a hardware watchdog that is able to reset the board when the system hangs. This section explains how to enable
the watchdog in Linux using
to check for system hangs and during reboot. By default, the watchdog is enabled in the Linux kernel but disabled in
systemd
s
.
ystemd
Watchdog Support in systemd
Systemd has included hardware watchdog support since version 183.
To activate watchdog support, the file
in
has to be adapted by enabling the options:
system.conf /etc/systemd/
RuntimeWatchdogSec=60s
ShutdownWatchdogSec=10min
RuntimeWatchdogSec defines the timeout value of the watchdog, while
defines the timeout when the system is rebooted. For
ShutdownWatchdogSec
more detailed information about hardware watchdogs under
can be found at
systemd
http://0pointer.de/blog/projects/watchdog.html
USB Host Controller
The USB controller of the i.MX 8M Plus SoC provides a low-cost connectivity solution for numerous consumer portable devices by providing a mechanism
for data transfer between USB devices with a line/bus speed up to
(SuperSpeed 'SS'). The USB subsystem has two independent USB controller
4 Gbit/s
cores. Both cores are capable of acting as a USB peripheral device or a USB host. Each is connected to a USB 3.0 PHY.
The unified BSP includes support for mass storage devices and keyboards. Other USB related device drivers must be enabled in the kernel configuration
on demand.
Due to
, all mass storage devices connected get unique IDs and can be found in
. These IDs can be used in
to mount the
udev
/dev/disks/by-id
/etc/fstab
different USB memory devices in different ways.
Both USB interfaces are configured as host in the kernel device tree
:
imx8mp-phyboard-pollux.dtsi
