[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 = 15;

static unsigned old_flags = 0;
ktime_t old_debounce_delay;
ktime_t old_settle_time;
ktime_t old_poll_time;
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: 15");

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);

	old_debounce_delay = gpio_evmi->debounce_delay;
	old_settle_time = gpio_evmi->settle_time;
	old_poll_time = gpio_evmi->poll_time;
	old_flags = gpio_evmi->flags;

	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);
	}

#if 0
	gpio_evmi->flags &= ~GPIOKPF_REMOVE_SOME_PHANTOM_KEYS;
#endif

	if (gpio_evmi->debounce_delay.tv.nsec != 0) {
		/* 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;
		}
	} else {
		/* Deactivating GPIOKPF_DEBOUNCE */
		printk(KERN_INFO PREFIX "Deactivating debounce\n");
		gpio_evmi->flags &= ~GPIOKPF_DEBOUNCE;
	}
	printk(KERN_INFO PREFIX "flags: 0x%x\n", gpio_evmi->flags);

	return 0;
}

static void __exit debounce_exit(void)
{
	if (gpio_evmi) {
		if (gpio_evmi->debounce_delay.tv.nsec != old_debounce_delay.tv.nsec) {
			printk(KERN_INFO PREFIX "Restoring debounce_delay\n");
			gpio_evmi->debounce_delay = old_debounce_delay;
			printk(KERN_INFO PREFIX "debounce_delay: %u\n", gpio_evmi->debounce_delay.tv.nsec);
		}
		if (gpio_evmi->flags != old_flags) {
			printk(KERN_INFO PREFIX "Restoring flags\n");
			gpio_evmi->flags = old_flags;
			printk(KERN_INFO PREFIX "flags: 0x%x\n", gpio_evmi->flags);
		}
		gpio_evmi->settle_time = old_settle_time;
		gpio_evmi->poll_time = old_poll_time;
	}
}

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
a4838b14	8	static int debounce_delay = 15;
ab5ed215	9
a4838b14	10	static unsigned old_flags = 0;
bb65757a MG	11	ktime_t old_debounce_delay;
	12	ktime_t old_settle_time;
	13	ktime_t old_poll_time;
1e65c113 MG	14	static struct gpio_event_matrix_info *gpio_evmi = NULL;
1e65c113 MG	15
b2b792eb	16	module_param(debounce_delay, int, S_IRUSR \| S_IRGRP \| S_IROTH);
a4838b14	17	MODULE_PARM_DESC(debounce_delay, "debouncing delay (ms), default: 15");
ab5ed215 MG	18
ab5ed215 MG	19	static int find_ms2_dev(struct device dev, void data)
d1ff9643 MG	20	{
d1ff9643 MG	21	if (!strncmp((char)data, dev_name(dev), strlen((char)data))) {
ab5ed215	22	printk(KERN_INFO PREFIX "Found it\n");
d1ff9643 MG	23	return 1;
	24	}
	25	return 0;
	26	}
b422e333 MG	27
	28	static int __init debounce_init(void)
	29	{
d1ff9643 MG	30	struct device *event_dev = NULL;
	31	struct gpio_event_platform_data *gpio_epd;
	32	struct gpio_event_info *gpio_ei;
d1ff9643	33
ab5ed215	34	printk(KERN_INFO PREFIX "Searching for " GPIO_EVENT_DEV_NAME "...\n");
d1ff9643 MG	35
	36
	37	event_dev = device_find_child(&platform_bus, GPIO_EVENT_DEV_NAME, find_ms2_dev);
	38	if (event_dev == NULL)
	39	return -ENODEV;
	40
	41	gpio_epd = (struct gpio_event_platform_data*)event_dev->platform_data;
ab5ed215	42	printk(KERN_INFO PREFIX "And there is a %s connected...\n", gpio_epd->name);
d1ff9643 MG	43	if (strcmp(gpio_epd->name, "sholes-keypad"))
	44	return -ENODEV;
	45
	46	gpio_ei = (struct gpio_event_info*)gpio_epd->info[0];
	47	gpio_evmi = container_of(gpio_ei, struct gpio_event_matrix_info, info);
	48
ab5ed215 MG	49	printk(KERN_INFO PREFIX "settle_time: %u\n", gpio_evmi->settle_time.tv.nsec);
	50	printk(KERN_INFO PREFIX "poll_time: %u\n", gpio_evmi->poll_time.tv.nsec);
	51	printk(KERN_INFO PREFIX "debounce_delay: %u\n", gpio_evmi->debounce_delay.tv.nsec);
	52	printk(KERN_INFO PREFIX "flags: 0x%x\n", gpio_evmi->flags);
20bf1c9e	53
bb65757a MG	54	old_debounce_delay = gpio_evmi->debounce_delay;
	55	old_settle_time = gpio_evmi->settle_time;
	56	old_poll_time = gpio_evmi->poll_time;
	57	old_flags = gpio_evmi->flags;
1e65c113	58
b2b792eb	59	if (gpio_evmi->debounce_delay.tv.nsec != debounce_delay * NSEC_PER_MSEC) {
ab5ed215	60	printk(KERN_INFO PREFIX "Changing debounce_delay\n");
b2b792eb	61	gpio_evmi->debounce_delay.tv.nsec = debounce_delay * NSEC_PER_MSEC;
ab5ed215	62	printk(KERN_INFO PREFIX "debounce_delay: %u\n", gpio_evmi->debounce_delay.tv.nsec);
d1ff9643 MG	63	}
d1ff9643 MG	64
bb65757a MG	65	#if 0
	66	gpio_evmi->flags &= ~GPIOKPF_REMOVE_SOME_PHANTOM_KEYS;
	67	#endif
a4838b14 MG	68
	69	if (gpio_evmi->debounce_delay.tv.nsec != 0) {
	70	/* GPIOKPF_DEBOUNCE should already be set by GPIOKPF_REMOVE_PHANTOM_KEYS */
	71	if (!(gpio_evmi->flags & GPIOKPF_DEBOUNCE)) {
	72	printk(KERN_INFO PREFIX "Activating debounce\n");
	73	gpio_evmi->flags \|= GPIOKPF_DEBOUNCE;
	74	}
	75	} else {
	76	/* Deactivating GPIOKPF_DEBOUNCE */
	77	printk(KERN_INFO PREFIX "Deactivating debounce\n");
	78	gpio_evmi->flags &= ~GPIOKPF_DEBOUNCE;
	79	}
	80	printk(KERN_INFO PREFIX "flags: 0x%x\n", gpio_evmi->flags);
	81
b422e333 MG	82	return 0;
	83	}
	84
	85	static void __exit debounce_exit(void)
	86	{
1e65c113	87	if (gpio_evmi) {
bb65757a	88	if (gpio_evmi->debounce_delay.tv.nsec != old_debounce_delay.tv.nsec) {
1e65c113	89	printk(KERN_INFO PREFIX "Restoring debounce_delay\n");
bb65757a	90	gpio_evmi->debounce_delay = old_debounce_delay;
1e65c113 MG	91	printk(KERN_INFO PREFIX "debounce_delay: %u\n", gpio_evmi->debounce_delay.tv.nsec);
1e65c113 MG	92	}
a4838b14 MG	93	if (gpio_evmi->flags != old_flags) {
	94	printk(KERN_INFO PREFIX "Restoring flags\n");
	95	gpio_evmi->flags = old_flags;
	96	printk(KERN_INFO PREFIX "flags: 0x%x\n", gpio_evmi->flags);
	97	}
bb65757a MG	98	gpio_evmi->settle_time = old_settle_time;
bb65757a MG	99	gpio_evmi->poll_time = old_poll_time;
1e65c113	100	}
b422e333 MG	101	}
	102
	103	module_init(debounce_init);
	104	module_exit(debounce_exit);
	105
	106	MODULE_LICENSE("GPL");
	107	MODULE_AUTHOR("Michael Gernoth <michael@gernoth.net>");