在系统中增加一个可唤醒中断--同时说明platform_device &platform_driver

    在系统休眠的时候3G来电或者短信需要唤醒系统，使系统resume。从3G模块手册看到有WAKE#脚，当收到来电或者SMS时这个脚会有0.5S的拉低，就是cp_wakeup_ap，用这个脚做唤醒脚。查看AP的datasheet，挑选一个带有EINT功能的GPIO脚做接收此中断的脚，这里选GPX3(1)。开始写驱动来处理这个事件。

kernel\arch\arm\mach-exynos\setup-mu609.c

 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/platform_device.h>
 #include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/skbuff.h>

 #include <plat/devs.h>
 #include <plat/sdhci.h>
 #include <plat/gpio-cfg.h>
 #include <mach/regs-gpio.h>
 #include <mach/gpio.h>
 #include <linux/irq.h>
 #include <linux/interrupt.h>
 #include <linux/module.h>

 static irqreturn_t host_wake_isr(int irq, void *dev)
 {
     /*
        do something when interrupt happen
     */
     return IRQ_HANDLED;
 }

 static int mu609_probe(struct platform_device *pdev)
 {
     int irq;
     int ret;

     printk("%s: start\n", __FUNCTION__);

     s3c_gpio_cfgpin(EXYNOS5410_GPX3(1), S3C_GPIO_INPUT); //stone++ for mu609
     s3c_gpio_setpull(EXYNOS5410_GPX3(1), S3C_GPIO_PULL_UP); //stone++ for mu609

     irq = IRQ_EINT(25);
     ret = request_irq(irq, host_wake_isr, IRQF_TRIGGER_FALLING,
         "3g mu609_wake", NULL);
     if (ret) {
         pr_err("[3G] Request_host wake irq failed.\n");
         return ret;
     }

     ret = irq_set_irq_wake(irq, 1);
     if (ret) {
         pr_err("[3G] Set_irq_wake failed.\n");
         return ret;
     }

     return ret;
 }

 static int mu609_remove(struct platform_device *pdev)
 {
     return 0;
 }


 static struct platform_driver mu609_driver = {
     .probe = mu609_probe,
     .remove = mu609_remove,
     .driver = {
            .name = "mu609_3g",
            .owner = THIS_MODULE,
            },
 };


 static struct platform_device mu609_device = {
     .name   = "mu609_3g",
     .id     = -1,
 };

 static int __init mu609_init(void)
 {
     int ret;

     ret = platform_driver_register(&mu609_driver);
     if(!ret){
         ret =  platform_device_register(&mu609_device);
         if (ret)
             platform_driver_unregister(&mu609_driver);
     }
     return ret;
 }
 late_initcall(mu609_init);

 

kernel\arch\arm\mach-exynos\Makefile

 obj-$(CONFIG_EXYNOS_DEV_MU609)  += setup-mu609.o

kernel\arch\arm\mach-exynos\Kconfig

 config EXYNOS_DEV_MU609
     bool "3G module MU609"
     default y
     help
       HuaWei mu609.