mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-12-03 18:10:13 +00:00
fd42f263ce
Many I2C devices produce roughly the same ACPI data with just things like the GPIO/interrupt information being different. This can be handled by a generic driver along with some information in the device tree. Add a generic i2c driver for this purpose. Signed-off-by: Simon Glass <sjg@chromium.org> Reviewed-by: Heiko Schocher <hs@denx.de>
42 lines
1.3 KiB
Text
42 lines
1.3 KiB
Text
I2C generic device
|
|
==================
|
|
|
|
This is used only to generate ACPI tables for an I2C device.
|
|
|
|
Required properties :
|
|
|
|
- compatible : "i2c-chip";
|
|
- reg : I2C chip address
|
|
- acpi,hid : HID name for the device
|
|
|
|
Optional properies in addition to device.txt:
|
|
|
|
- reset-gpios : GPIO used to assert reset to the device
|
|
- irq-gpios : GPIO used for interrupt (if Interrupt is not used)
|
|
- stop-gpios : GPIO used to stop the device
|
|
- interrupts-extended : Interrupt to use for the device
|
|
- reset-delay-ms : Delay after de-asserting reset, in ms
|
|
- reset-off-delay-ms : Delay after asserting reset (during power off)
|
|
- enable-delay-ms : Delay after asserting enable
|
|
- enable-off-delay-ms : Delay after de-asserting enable (during power off)
|
|
- stop-delay-ms : Delay after de-aserting stop
|
|
- stop-off-delay-ms : Delay after asserting stop (during power off)
|
|
- hid-descr-addr : HID register offset (for Human Interface Devices)
|
|
|
|
Example
|
|
-------
|
|
|
|
elan-touchscreen@10 {
|
|
compatible = "i2c-chip";
|
|
reg = <0x10>;
|
|
acpi,hid = "ELAN0001";
|
|
acpi,ddn = "ELAN Touchscreen";
|
|
interrupts-extended = <&acpi_gpe GPIO_21_IRQ
|
|
IRQ_TYPE_EDGE_FALLING>;
|
|
linux,probed;
|
|
reset-gpios = <&gpio_n GPIO_36 GPIO_ACTIVE_HIGH>;
|
|
reset-delay-ms = <20>;
|
|
enable-gpios = <&gpio_n GPIO_152 GPIO_ACTIVE_HIGH>;
|
|
enable-delay-ms = <1>;
|
|
acpi,has-power-resource;
|
|
};
|