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IRQ

Introduction

IRQ (Interrupt Request) refers to the interrupt requests from devices. The driver provides a set of functions for managing hardware and software interrupts. This module provides interfaces for registering and deregistering both hardware and software interrupts, enabling and disabling interrupts, and managing the pending status of interrupts.

Function List

  1. Register Hardware Interrupt Vector — Attach a hardware interrupt vector and replace the software vector.

  2. Deregister Hardware Interrupt Vector — Detach a hardware interrupt vector.

  3. Register Software Interrupt Vector — Attach a software interrupt vector and callback function.

  4. Deregister Software Interrupt Vector — Detach a software interrupt vector.

  5. Disable and Save Interrupt State — Disable global interrupts and save the previous state.

  6. Restore Interrupt State — Enable global interrupts using the previously saved state.

  7. Enable Interrupt — Enable a specified interrupt.

  8. Disable Interrupt — Disable a specified interrupt.

  9. Set Interrupt Pending — Set a specified interrupt to the pending state.

  10. Clear Interrupt Pending — Clear the pending state of a specified interrupt.

  11. Set Wakeup Interrupt — Set a specified interrupt as a wakeup interrupt.

Function Overview

The diagram below illustrates the management of the interrupt vector table.

Interrupt Vector Table Diagram

In interrupt management, a set of software interrupt registration mechanisms is provided. In principle, users only need to register the software table. For performance considerations, interfaces for directly writing to the hardware vector table are also provided. Note that when registering both hardware and software interrupts on the same interrupt vector, the hardware interrupt has higher priority and will overwrite the corresponding software interrupt, causing the software interrupt to fail. If a hardware interrupt is registered first, followed by a software interrupt, the software interrupt cannot be registered.

Main Functions

Registering Hardware Interrupt Vector

Call the function wm_drv_irq_attach_hw_vector() to register a hardware interrupt vector and replace the software vector. Example:

void irq_callback(void) {
}

wm_drv_irq_attach_hw_vector(WM_IRQ_I2C, irq_callback);

The first parameter is the interrupt number. The W800 chip has 32 interrupt numbers, each corresponding to an interrupt source on the W800 chip. The type is wm_irq_no_t.

The second parameter is the interrupt callback function, of type wm_drv_hw_irq_handle.

Detaching a Hardware Interrupt Vector

The function wm_drv_irq_detach_hw_vector() is called to detach a hardware interrupt vector. An example is as follows:

wm_drv_irq_detach_hw_vector(WM_IRQ_I2C);

The parameter is the interrupt number, of type wm_irq_no_t.

Registering a Software Interrupt Vector

The function wm_drv_irq_attach_sw_vector() is called to attach a software interrupt vector and a callback function. An example is as follows:

void irq_callback(void *arg) {
}

wm_drv_irq_attach_sw_vector(WM_IRQ_I2C, irq_callback, NULL);

The first parameter is the interrupt number, of type wm_irq_no_t.

The second parameter is the interrupt callback function, of type wm_drv_sw_irq_handle.

The third parameter is user data, of type void *.

Detaching a Software Interrupt Vector

The function wm_drv_irq_detach_sw_vector() is called to detach a software interrupt vector. An example is as follows:

wm_drv_irq_detach_sw_vector(WM_IRQ_I2C);

The parameter is the interrupt number, of type wm_irq_no_t.

Saving and Disabling Interrupt State

The function wm_drv_irq_save() is called to disable interrupts and save the previous state. An example is as follows:

uint32_t irq_state;
irq_state = wm_drv_irq_save();

This function returns the previous interrupt state, of type uint32_t.

Restoring Interrupt State

The function wm_drv_irq_restore() is called to enable interrupts using the previously saved state. An example is as follows:

.. code:: c

uint32_t irq_state; irq_state = wm_drv_irq_save();

wm_drv_irq_restore(irq_state);

Here, irq_state is used to save the interrupt state, which can then be used to restore the interrupt state. The parameter is the previously saved interrupt state, of type uint32_t.

Enabling an Interrupt

The function wm_drv_irq_enable() is called to enable a specified interrupt. An example is as follows:

wm_drv_irq_enable(WM_IRQ_I2C);

The parameter is the interrupt number, of type wm_irq_no_t.

Disabling an Interrupt

The function wm_drv_irq_disable() is called to disable a specified interrupt. An example is as follows:

wm_drv_irq_disable(WM_IRQ_I2C);

The parameter is the interrupt number, of type wm_irq_no_t.

Setting an Interrupt Pending

The function``wm_drv_irq_set_pending()`` is called to set a specified interrupt to the pending state. An example is as follows:

wm_drv_irq_set_pending(WM_IRQ_I2C);

The parameter is the interrupt number, of type wm_irq_no_t.

Clearing an Interrupt Pending

The function wm_drv_irq_clear_pending() is called to clear the pending state of a specified interrupt. An example is as follows:

.. code:: c

wm_drv_irq_clear_pending(WM_IRQ_I2C);

The parameter is the interrupt number, of type wm_irq_no_t.

Setting Wakeup Interrupt

The function wm_drv_irq_set_wakeup() is called to set a specified interrupt as a wakeup interrupt. When the device is in low-power mode, a wakeup interrupt can trigger the device to resume normal operation from the low-power mode. An example is as follows:

wm_drv_irq_set_wakeup(WM_IRQ_I2C);

The parameter is the interrupt number, of type wm_irq_no_t.

API Reference

To find IRQ-related APIs, please refer to:

IRQ API Reference