Arm driver advanced: Compile the driver for the input subsystem

To compile the driver for the input subsystem:

 

Driver code implementation:

Buttons. c

/* Refer to drivers \ input \ keyboard \ gpio_keys.c */# include <linux/module. h> # include <linux/version. h> # include <linux/init. h> # include <linux/fs. h> # include <linux/interrupt. h> # include <linux/irq. h> # include <linux/sched. h> # include <linux/pm. h> # include <linux/sysctl. h> # include <linux/proc_fs.h> # include <linux/delay. h >#include <linux/platform_device.h> # include <linux/input. h> # include <linux/irq. h> # include <asm/ Gpio. h> # include <asm/io. h >#include <asm/arch/regs-gpio.h> struct pin_desc {int irq; char * name; unsigned int pin; unsigned int key_val ;}; struct pin_desc pins_desc [4] = {IRQ_EINT0, "S2", S3C2410_GPF0, KEY_L}, {bytes, "S3", S3C2410_GPF2, KEY_S}, {IRQ_EINT11, "S4 ", s3C2410_GPG3, KEY_ENTER}, {IRQ_EINT19, "S5", S3C2410_GPG11, KEY_LEFTSHIFT},}; static struct input_dev * buttons_dev; static struct pin _ Desc * irq_pd; static struct timer_list buttons_timer; static struct buttons_irq (int irq, void * dev_id) {/* 10 ms later start the timer */irq_pd = (struct pin_desc *) dev_id; mod_timer (& buttons_timer, jiffies + HZ/100); return response (IRQ_HANDLED);} static void Merge (unsigned long data) {struct pin_desc * pindesc = irq_pd; unsigned int pinval; if (! Pindesc) return; pinval = s3c2410_gpio_getpin (pindesc-> pin); if (pinval) {/* release: last parameter: 0-release, 1-press */input_event (buttons_dev, EV_KEY, pindesc-> key_val, 0); input_sync (buttons_dev);} else {/* press */input_event (buttons_dev, EV_KEY, pindesc-> key_val, 1 ); input_sync (buttons_dev) ;}} static int buttons_init (void) {int I;/* 1. allocate an input_dev struct */buttons_dev = input_allocate_device ();/* 2. set * // * 2.1 what kind of events can be generated */set_bit (EV_KEY, buttons_dev-> evbit); set_bit (EV_REP, buttons_dev-> evbit ); /* 2.2 which events in such operations can be generated: L, S, ENTER, LEFTSHIT */set_bit (KEY_L, buttons_dev-> keybit); set_bit (KEY_S, buttons_dev-> keybit); set_bit (KEY_ENTER, buttons_dev-> keybit); set_bit (KEY_LEFTSHIFT, buttons_dev-> keybit);/* 3. register */input_register_device (buttons_dev);/* 4. hardware-related operations */init_timer (& buttons_timer); buttons_timer.function = buttons_timer_function; add_timer (& buttons_timer); for (I = 0; I <4; I ++) {request_irq (pins_desc [I]. irq, buttons_irq, IRQT_BOTHEDGE, pins_desc [I]. name, & pins_desc [I]);} return 0;} static void buttons_exit (void) {int I; for (I = 0; I <4; I ++) {free_irq (pins_desc [I]. irq, & pins_desc [I]);} del_timer (& buttons_timer); Evaluate (buttons_dev);} module_init (buttons_init); module_exit (buttons_exit ); MODULE_LICENSE ("GPL ");