enable_ irq_ Wake interrupt wakes up the kernel in low power mode

Low power mode

Implement all of your drivers supend and resume function . Register an interrupt wakeup source , It's usually GPIO,RTC interrupt . And then call echo mem > state Suspend the system in memory , Now SDRAM It's going on self-refresh The action of . The basic power consumption is here

at present 2.6.kernel It's ready for you . You just need to follow the interface function in each driver suspend(...), and resume() Drive this suspend and resume complete . Because of the call apm After the command ,kernel Will call the... In your registered driver in turn suspend function , Put all kinds of peripherals into power saving mode . Last CPU Get into power down Pattern same , When used RTC perhaps GPIO One of them will cpu from power down Mode wake up . In turn, it will call the... In each driver resume Function wakes up the peripheral , Enter the normal working state . Of course, you have to define the interrupt wakeup source yourself enable_irq_wake(irq);

in addition , stay 2.6 in , To drive suspend Add the code for the corresponding equipment to enter the power saving state , stay resume Add the code for the corresponding device to return to the normal working mode from low power consumption .

When the keyboard driver is initialized, add enable_irq_wake, When the key is interrupted , You can wake up the sleepy kernel

 

Interrupt operations are often used when writing drivers , Some interrupt configuration functions have been written in the kernel driver for easy use , And gpio It is better to use the operation configuration function together .
void disable_irq(unsigned int); // Turn off the corresponding interrupt number
void enable_irq(unsigned int);// Turn on the corresponding interrupt number
int set_irq_type(unsigned int irq, unsigned int type);// Set the trigger mode of interrupt
void disable_irq_wake(unsigned int irq); // Disable interrupt wake-up function
void enable_irq_wake(unsigned int irq);// Enable interrupt wake-up function

 

The following steps should be completed during driver initialization of external interrupts :
1. Set the corresponding pin to interrupt function
2. Set interrupt type (IRQ perhaps FIQ)
3. Set the trigger mode
4. Enable this interrupt
Function interface for setting trigger mode
int set_irq_type(unsigned int irq, unsigned int type);
interrupt pending register , It is mainly used to identify which interrupt is generated .