Hi,
I'm implementing device-model backed bootcount which uses I2C EEPROM chip. I've
found following device tree, which I'm replicating:
https://source.denx.de/u-boot/u-boot/-/blob/master/arch/arm/dts/imx53-ppd.dts
https://source.denx.de/u-boot/u-boot/-/blob/master/arch/arm/dts/imx53-ppd-uboot.dtsi
Here is the important code snippet from `imx53-ppd-uboot.dtsi`. As you can see,
the `bootcount` partition from eeprom is referenced as the `i2c-eeprom` device
in `bootcount` device.
/ {
bootcount {
compatible = "u-boot,bootcount-i2c-eeprom";
i2c-eeprom = <&bootcount>;
};
};
&eeprom {
partitions {
compatible = "fixed-partitions";
#address-cells = <1>;
#size-cells = <1>;
vpd@0 {
reg = <0 800>;
};
bootcount: bootcount@1022 {
reg = <1022 2>;
};
};
};
Here you can see my snippet from `imx7-colibri-u-boot.dtsi`, where that I have
to reference not the partition but the whole eeprom device, because otherwise
I'll get following error: "bootcount: could not get backing device".
/ {
bootcount {
compatible = "u-boot,bootcount-i2c-eeprom";
i2c-eeprom = <&eeprom>;
};
};
&eeprom {
partitions {
compatible = "fixed-partitions";
#address-cells = <1>;
#size-cells = <1>;
bootcount: bootcount@0 {
reg = <0 2>;
};
};
};
The question is what I'm missing? Why referencing the whole eeprom works, but
referencing a single partition not. Do you have any idea?
Thank you very much
Richard Forro
P.S. there is no problem with the definition of eeprom inside the
`imx7-colibri.dtsi` file. It is exactly the same as in `imx53-ppd.dts`.
&i2c4 {
pinctrl-names = "default", "gpio";
pinctrl-0 = <&pinctrl_i2c4>;
pinctrl-1 = <&pinctrl_i2c4_gpio>;
sda-gpios = <&gpio7 9 GPIO_ACTIVE_LOW>;
scl-gpios = <&gpio7 8 GPIO_ACTIVE_LOW>;
status = "okay";
eeprom: eeprom@50 {
compatible = "atmel,24c02"; /* our at34c02d is semi-compatible
*/
reg = <0x50>;
pagesize = <16>;
};
};
