(adding Przemyslaw who uses the I2C GPIO driver)
Hi,
On 25 May 2015 at 22:30, Heiko Schocher hs@denx.de wrote:
Hello Matt,
Am 22.05.2015 16:35, schrieb Matt Wood:
Hi all, I am trying to get a bitbanged i2c port working with u-boot on an Atmel SAMA5D3 platform. I have added DT bindings to support the I2C drivers however when I try to select the bus on the u-boot command line I consistently get an error in gpio-uclass:
I am not sure, if DM is supported on this plattform yet, I added Andreas Biesmann (AT91) and Simon Glass (DM) to Cc, maybe one of them can help you here ...
bye, Heiko
_gpio_request_by_name_nodev: uclass_get_device_by_of_offset failed
_gpio_request_by_name_nodev: Node 'soft-i2c@1', property 'gpios', failed to request GPIO index 0: -19
Each driver always fails at the get_dev_by_offset routine.
I suspect some issue with the way the GPIO is defined or is not setup correctly. Has anyone seen this or have any advice on where to look?
This is the relevant part of the device tree:
aliases {
i2c0 = "/soft-i2c@1";};
soft-i2c@1 {
#address-cells = <1>; #size-cells = <0>;/* compatible = "soft-i2c"; */
compatible = "i2c-gpio";/* clock-frequency = <100000>; */
/* pinctrl-names = "default";
pinctrl-0 = <&pinctrl_soft_i2c>; */ /* Define the proper GPIO pins *//*
clock-pin = <&pioA 31 0>; data-pin = <&pioA 30 0>; */ gpios = <&pioA 30 0 /* SDA */ &pioA 31 0>; /* SCL */ i2c-gpio,sda-open-drain; i2c-gpio,scl-open-drain; i2c-gpio,delay-us =<3>; };};
Can you post the output of 'dm tree' and 'dm uclass'? I wonder if your GPIO driver is not connected up properly?
Are you using i2c-gpio.c? That driver should work as is on any platform with only device tree additions.
Regards, Simon