[ms2-fixes] / debounce.c

#include <linux/module.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/gpio_event.h>

#define PREFIX "debounce: "

static int debounce_delay = 10;

static int old_delay = 0;
static struct gpio_event_matrix_info *gpio_evmi = NULL;

module_param(debounce_delay, int, S_IRUSR | S_IRGRP | S_IROTH);
MODULE_PARM_DESC(debounce_delay, "debouncing delay (ms), default: 10");

static int find_ms2_dev(struct device *dev, void *data)
{
	if (!strncmp((char*)data, dev_name(dev), strlen((char*)data))) {
		printk(KERN_INFO PREFIX "Found it\n");
		return 1;
	}
	return 0;
}

static int __init debounce_init(void)
{
	struct device *event_dev = NULL;
	struct gpio_event_platform_data *gpio_epd;
	struct gpio_event_info *gpio_ei;

	printk(KERN_INFO PREFIX "Searching for " GPIO_EVENT_DEV_NAME "...\n");

	
	event_dev = device_find_child(&platform_bus, GPIO_EVENT_DEV_NAME, find_ms2_dev);
	if (event_dev == NULL)
		return -ENODEV;

	gpio_epd = (struct gpio_event_platform_data*)event_dev->platform_data;
	printk(KERN_INFO PREFIX "And there is a %s connected...\n", gpio_epd->name);
	if (strcmp(gpio_epd->name, "sholes-keypad"))
		return -ENODEV;

	gpio_ei = (struct gpio_event_info*)gpio_epd->info[0];
	gpio_evmi = container_of(gpio_ei, struct gpio_event_matrix_info, info);

	printk(KERN_INFO PREFIX "settle_time: %u\n", gpio_evmi->settle_time.tv.nsec);
	printk(KERN_INFO PREFIX "poll_time: %u\n", gpio_evmi->poll_time.tv.nsec);
	printk(KERN_INFO PREFIX "debounce_delay: %u\n", gpio_evmi->debounce_delay.tv.nsec);
	printk(KERN_INFO PREFIX "flags: 0x%x\n", gpio_evmi->flags);

	/* GPIOKPF_DEBOUNCE should already be set by GPIOKPF_REMOVE_PHANTOM_KEYS */
	if (!(gpio_evmi->flags & GPIOKPF_DEBOUNCE)) {
		printk(KERN_INFO PREFIX "Activating debounce\n");
		gpio_evmi->flags |= GPIOKPF_DEBOUNCE;
		printk(KERN_INFO PREFIX "flags: 0x%x\n", gpio_evmi->flags);
	}

	old_delay = gpio_evmi->debounce_delay.tv.nsec;

	if (gpio_evmi->debounce_delay.tv.nsec != debounce_delay * NSEC_PER_MSEC) {
		printk(KERN_INFO PREFIX "Changing debounce_delay\n");
		gpio_evmi->debounce_delay.tv.nsec = debounce_delay * NSEC_PER_MSEC;
		printk(KERN_INFO PREFIX "debounce_delay: %u\n", gpio_evmi->debounce_delay.tv.nsec);
	}

	return 0;
}

static void __exit debounce_exit(void)
{
	if (gpio_evmi) {
		if (gpio_evmi->debounce_delay.tv.nsec != old_delay) {
			printk(KERN_INFO PREFIX "Restoring debounce_delay\n");
			gpio_evmi->debounce_delay.tv.nsec = old_delay;
			printk(KERN_INFO PREFIX "debounce_delay: %u\n", gpio_evmi->debounce_delay.tv.nsec);
		}
	}
}

module_init(debounce_init);
module_exit(debounce_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Michael Gernoth <michael@gernoth.net>");
Commit	Line	Data
b422e333	1	#include <linux/module.h>
d1ff9643 MG	2	#include <linux/device.h>
	3	#include <linux/platform_device.h>
	4	#include <linux/gpio_event.h>
	5
ab5ed215 MG	6	#define PREFIX "debounce: "
ab5ed215 MG	7
b2b792eb	8	static int debounce_delay = 10;
ab5ed215	9
1e65c113 MG	10	static int old_delay = 0;
	11	static struct gpio_event_matrix_info *gpio_evmi = NULL;
	12
b2b792eb MG	13	module_param(debounce_delay, int, S_IRUSR \| S_IRGRP \| S_IROTH);
b2b792eb MG	14	MODULE_PARM_DESC(debounce_delay, "debouncing delay (ms), default: 10");
ab5ed215 MG	15
ab5ed215 MG	16	static int find_ms2_dev(struct device dev, void data)
d1ff9643 MG	17	{
d1ff9643 MG	18	if (!strncmp((char)data, dev_name(dev), strlen((char)data))) {
ab5ed215	19	printk(KERN_INFO PREFIX "Found it\n");
d1ff9643 MG	20	return 1;
	21	}
	22	return 0;
	23	}
b422e333 MG	24
	25	static int __init debounce_init(void)
	26	{
d1ff9643 MG	27	struct device *event_dev = NULL;
	28	struct gpio_event_platform_data *gpio_epd;
	29	struct gpio_event_info *gpio_ei;
d1ff9643	30
ab5ed215	31	printk(KERN_INFO PREFIX "Searching for " GPIO_EVENT_DEV_NAME "...\n");
d1ff9643 MG	32
	33
	34	event_dev = device_find_child(&platform_bus, GPIO_EVENT_DEV_NAME, find_ms2_dev);
	35	if (event_dev == NULL)
	36	return -ENODEV;
	37
	38	gpio_epd = (struct gpio_event_platform_data*)event_dev->platform_data;
ab5ed215	39	printk(KERN_INFO PREFIX "And there is a %s connected...\n", gpio_epd->name);
d1ff9643 MG	40	if (strcmp(gpio_epd->name, "sholes-keypad"))
	41	return -ENODEV;
	42
	43	gpio_ei = (struct gpio_event_info*)gpio_epd->info[0];
	44	gpio_evmi = container_of(gpio_ei, struct gpio_event_matrix_info, info);
	45
ab5ed215 MG	46	printk(KERN_INFO PREFIX "settle_time: %u\n", gpio_evmi->settle_time.tv.nsec);
	47	printk(KERN_INFO PREFIX "poll_time: %u\n", gpio_evmi->poll_time.tv.nsec);
	48	printk(KERN_INFO PREFIX "debounce_delay: %u\n", gpio_evmi->debounce_delay.tv.nsec);
	49	printk(KERN_INFO PREFIX "flags: 0x%x\n", gpio_evmi->flags);
20bf1c9e	50
ab5ed215 MG	51	/* GPIOKPF_DEBOUNCE should already be set by GPIOKPF_REMOVE_PHANTOM_KEYS */
	52	if (!(gpio_evmi->flags & GPIOKPF_DEBOUNCE)) {
	53	printk(KERN_INFO PREFIX "Activating debounce\n");
20bf1c9e	54	gpio_evmi->flags \|= GPIOKPF_DEBOUNCE;
ab5ed215 MG	55	printk(KERN_INFO PREFIX "flags: 0x%x\n", gpio_evmi->flags);
	56	}
	57
1e65c113 MG	58	old_delay = gpio_evmi->debounce_delay.tv.nsec;
1e65c113 MG	59
b2b792eb	60	if (gpio_evmi->debounce_delay.tv.nsec != debounce_delay * NSEC_PER_MSEC) {
ab5ed215	61	printk(KERN_INFO PREFIX "Changing debounce_delay\n");
b2b792eb	62	gpio_evmi->debounce_delay.tv.nsec = debounce_delay * NSEC_PER_MSEC;
ab5ed215	63	printk(KERN_INFO PREFIX "debounce_delay: %u\n", gpio_evmi->debounce_delay.tv.nsec);
d1ff9643 MG	64	}
d1ff9643 MG	65
b422e333 MG	66	return 0;
	67	}
	68
	69	static void __exit debounce_exit(void)
	70	{
1e65c113 MG	71	if (gpio_evmi) {
	72	if (gpio_evmi->debounce_delay.tv.nsec != old_delay) {
	73	printk(KERN_INFO PREFIX "Restoring debounce_delay\n");
	74	gpio_evmi->debounce_delay.tv.nsec = old_delay;
	75	printk(KERN_INFO PREFIX "debounce_delay: %u\n", gpio_evmi->debounce_delay.tv.nsec);
	76	}
	77	}
b422e333 MG	78	}
	79
	80	module_init(debounce_init);
	81	module_exit(debounce_exit);
	82
	83	MODULE_LICENSE("GPL");
	84	MODULE_AUTHOR("Michael Gernoth <michael@gernoth.net>");