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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>
43 lines
1.3 KiB
Plaintext
43 lines
1.3 KiB
Plaintext
I2C generic device
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==================
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This is used only to generate ACPI tables for an I2C device.
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Required properties :
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- compatible : "i2c-chip";
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- reg : I2C chip address
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- acpi,hid : HID name for the device
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Optional properies in addition to device.txt:
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- reset-gpios : GPIO used to assert reset to the device
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- irq-gpios : GPIO used for interrupt (if Interrupt is not used)
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- stop-gpios : GPIO used to stop the device
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- interrupts-extended : Interrupt to use for the device
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- reset-delay-ms : Delay after de-asserting reset, in ms
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- reset-off-delay-ms : Delay after asserting reset (during power off)
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- enable-delay-ms : Delay after asserting enable
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- enable-off-delay-ms : Delay after de-asserting enable (during power off)
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- stop-delay-ms : Delay after de-aserting stop
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- stop-off-delay-ms : Delay after asserting stop (during power off)
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- hid-descr-addr : HID register offset (for Human Interface Devices)
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Example
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-------
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elan-touchscreen@10 {
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compatible = "i2c-chip";
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reg = <0x10>;
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acpi,hid = "ELAN0001";
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acpi,ddn = "ELAN Touchscreen";
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interrupts-extended = <&acpi_gpe GPIO_21_IRQ
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IRQ_TYPE_EDGE_FALLING>;
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linux,probed;
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reset-gpios = <&gpio_n GPIO_36 GPIO_ACTIVE_HIGH>;
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reset-delay-ms = <20>;
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enable-gpios = <&gpio_n GPIO_152 GPIO_ACTIVE_HIGH>;
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enable-delay-ms = <1>;
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acpi,has-power-resource;
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};
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