98 lines
3.3 KiB
Plaintext
98 lines
3.3 KiB
Plaintext
|
Spreadtrum EIC controller bindings
|
||
|
|
|
||
|
|
The EIC is the abbreviation of external interrupt controller, which can
|
||
|
|
be used only in input mode. The Spreadtrum platform has 2 EIC controllers,
|
||
|
|
one is in digital chip, and another one is in PMIC. The digital chip EIC
|
||
|
|
controller contains 4 sub-modules: EIC-debounce, EIC-latch, EIC-async and
|
||
|
|
EIC-sync. But the PMIC EIC controller contains only one EIC-debounce sub-
|
||
|
|
module.
|
||
|
|
|
||
|
|
The EIC-debounce sub-module provides up to 8 source input signal
|
||
|
|
connections. A debounce mechanism is used to capture the input signals'
|
||
|
|
stable status (millisecond resolution) and a single-trigger mechanism
|
||
|
|
is introduced into this sub-module to enhance the input event detection
|
||
|
|
reliability. In addition, this sub-module's clock can be shut off
|
||
|
|
automatically to reduce power dissipation. Moreover the debounce range
|
||
|
|
is from 1ms to 4s with a step size of 1ms. The input signal will be
|
||
|
|
ignored if it is asserted for less than 1 ms.
|
||
|
|
|
||
|
|
The EIC-latch sub-module is used to latch some special power down signals
|
||
|
|
and generate interrupts, since the EIC-latch does not depend on the APB
|
||
|
|
clock to capture signals.
|
||
|
|
|
||
|
|
The EIC-async sub-module uses a 32kHz clock to capture the short signals
|
||
|
|
(microsecond resolution) to generate interrupts by level or edge trigger.
|
||
|
|
|
||
|
|
The EIC-sync is similar with GPIO's input function, which is a synchronized
|
||
|
|
signal input register. It can generate interrupts by level or edge trigger
|
||
|
|
when detecting input signals.
|
||
|
|
|
||
|
|
Required properties:
|
||
|
|
- compatible: Should be one of the following:
|
||
|
|
"sprd,sc9860-eic-debounce",
|
||
|
|
"sprd,sc9860-eic-latch",
|
||
|
|
"sprd,sc9860-eic-async",
|
||
|
|
"sprd,sc9860-eic-sync",
|
||
|
|
"sprd,sc2731-eic".
|
||
|
|
- reg: Define the base and range of the I/O address space containing
|
||
|
|
the GPIO controller registers.
|
||
|
|
- gpio-controller: Marks the device node as a GPIO controller.
|
||
|
|
- #gpio-cells: Should be <2>. The first cell is the gpio number and
|
||
|
|
the second cell is used to specify optional parameters.
|
||
|
|
- interrupt-controller: Marks the device node as an interrupt controller.
|
||
|
|
- #interrupt-cells: Should be <2>. Specifies the number of cells needed
|
||
|
|
to encode interrupt source.
|
||
|
|
- interrupts: Should be the port interrupt shared by all the gpios.
|
||
|
|
|
||
|
|
Example:
|
||
|
|
eic_debounce: gpio@40210000 {
|
||
|
|
compatible = "sprd,sc9860-eic-debounce";
|
||
|
|
reg = <0 0x40210000 0 0x80>;
|
||
|
|
gpio-controller;
|
||
|
|
#gpio-cells = <2>;
|
||
|
|
interrupt-controller;
|
||
|
|
#interrupt-cells = <2>;
|
||
|
|
interrupts = <GIC_SPI 52 IRQ_TYPE_LEVEL_HIGH>;
|
||
|
|
};
|
||
|
|
|
||
|
|
eic_latch: gpio@40210080 {
|
||
|
|
compatible = "sprd,sc9860-eic-latch";
|
||
|
|
reg = <0 0x40210080 0 0x20>;
|
||
|
|
gpio-controller;
|
||
|
|
#gpio-cells = <2>;
|
||
|
|
interrupt-controller;
|
||
|
|
#interrupt-cells = <2>;
|
||
|
|
interrupts = <GIC_SPI 52 IRQ_TYPE_LEVEL_HIGH>;
|
||
|
|
};
|
||
|
|
|
||
|
|
eic_async: gpio@402100a0 {
|
||
|
|
compatible = "sprd,sc9860-eic-async";
|
||
|
|
reg = <0 0x402100a0 0 0x20>;
|
||
|
|
gpio-controller;
|
||
|
|
#gpio-cells = <2>;
|
||
|
|
interrupt-controller;
|
||
|
|
#interrupt-cells = <2>;
|
||
|
|
interrupts = <GIC_SPI 52 IRQ_TYPE_LEVEL_HIGH>;
|
||
|
|
};
|
||
|
|
|
||
|
|
eic_sync: gpio@402100c0 {
|
||
|
|
compatible = "sprd,sc9860-eic-sync";
|
||
|
|
reg = <0 0x402100c0 0 0x20>;
|
||
|
|
gpio-controller;
|
||
|
|
#gpio-cells = <2>;
|
||
|
|
interrupt-controller;
|
||
|
|
#interrupt-cells = <2>;
|
||
|
|
interrupts = <GIC_SPI 52 IRQ_TYPE_LEVEL_HIGH>;
|
||
|
|
};
|
||
|
|
|
||
|
|
pmic_eic: gpio@300 {
|
||
|
|
compatible = "sprd,sc2731-eic";
|
||
|
|
reg = <0x300>;
|
||
|
|
interrupt-parent = <&sc2731_pmic>;
|
||
|
|
interrupts = <5 IRQ_TYPE_LEVEL_HIGH>;
|
||
|
|
gpio-controller;
|
||
|
|
#gpio-cells = <2>;
|
||
|
|
interrupt-controller;
|
||
|
|
#interrupt-cells = <2>;
|
||
|
|
};
|