[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 ssize_t show_debounce_delay(struct device *dev, struct device_attribute *attr, char *buf)
{
	if (!gpio_evmi) 
		return -ENODEV;

	return snprintf(buf, PAGE_SIZE, "%ld\n", (gpio_evmi->debounce_delay.tv.nsec / NSEC_PER_MSEC));
}

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

	if (gpio_evmi->debounce_delay.tv.nsec != 0) {
		if (!(gpio_evmi->flags & GPIOKPF_DEBOUNCE)) {
			printk(KERN_INFO PREFIX "Activating debounce\n");
			gpio_evmi->flags |= GPIOKPF_DEBOUNCE;
		}
	} else {
		if (gpio_evmi->flags & GPIOKPF_DEBOUNCE) {
			printk(KERN_INFO PREFIX "Deactivating debounce\n");
			gpio_evmi->flags &= ~GPIOKPF_DEBOUNCE;
		}
	}
}

static ssize_t store_debounce_delay(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
{
	long int delay;

	if (!gpio_evmi) 
		return -ENODEV;

	sscanf(buf, "%ld", &delay);
	set_debounce_delay(delay);

	return strnlen(buf, PAGE_SIZE);
}

static ssize_t show_settle_time(struct device *dev, struct device_attribute *attr, char *buf)
{
	if (!gpio_evmi) 
		return -ENODEV;

	return snprintf(buf, PAGE_SIZE, "%ld\n", (gpio_evmi->settle_time.tv.nsec / NSEC_PER_USEC));
}

static ssize_t store_settle_time(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
{
	long int delay;

	if (!gpio_evmi) 
		return -ENODEV;

	sscanf(buf, "%ld", &delay);
	gpio_evmi->settle_time.tv.nsec = delay * NSEC_PER_USEC;

	return strnlen(buf, PAGE_SIZE);
}

static ssize_t show_poll_time(struct device *dev, struct device_attribute *attr, char *buf)
{
	if (!gpio_evmi) 
		return -ENODEV;

	return snprintf(buf, PAGE_SIZE, "%ld\n", (gpio_evmi->poll_time.tv.nsec / NSEC_PER_MSEC));
}

static ssize_t store_poll_time(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
{
	long int delay;

	if (!gpio_evmi) 
		return -ENODEV;

	sscanf(buf, "%ld", &delay);
	gpio_evmi->poll_time.tv.nsec = delay * NSEC_PER_MSEC;

	return strnlen(buf, PAGE_SIZE);
}

static ssize_t show_flags(struct device *dev, struct device_attribute *attr, char *buf)
{
	if (!gpio_evmi) 
		return -ENODEV;

	return snprintf(buf, PAGE_SIZE, "0x%x\n", gpio_evmi->flags);
}

static ssize_t store_flags(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
{
	unsigned flags;

	if (!gpio_evmi) 
		return -ENODEV;

	sscanf(buf, "0x%x", &flags);
	gpio_evmi->flags = flags;

	return strnlen(buf, PAGE_SIZE);
}

static DEVICE_ATTR(debounce_delay, (S_IRUGO | S_IWUGO), &show_debounce_delay, store_debounce_delay);
static DEVICE_ATTR(settle_time, (S_IRUGO | S_IWUGO), &show_settle_time, store_settle_time);
static DEVICE_ATTR(poll_time, (S_IRUGO | S_IWUGO), &show_poll_time, store_poll_time);
static DEVICE_ATTR(flags, (S_IRUGO | S_IWUGO), &show_flags, store_flags);

static void debounce_release(struct device *dev)
{
}

static struct device debounce_device = {
	.init_name = "debounce",
	.release = debounce_release,
};

static int __init debounce_init(void)
{
	struct device *event_dev = NULL;
	struct gpio_event_platform_data *gpio_epd;
	struct gpio_event_info *gpio_ei;
	int err = 0;

	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);

	err = device_register(&debounce_device);
	if (err) {
		return err;
	}

	err = device_create_file(&debounce_device, &dev_attr_debounce_delay);
	err = device_create_file(&debounce_device, &dev_attr_settle_time);
	err = device_create_file(&debounce_device, &dev_attr_poll_time);
	err = device_create_file(&debounce_device, &dev_attr_flags);

	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;

	set_debounce_delay(debounce_delay);
#if 0
	gpio_evmi->flags &= ~GPIOKPF_REMOVE_SOME_PHANTOM_KEYS;
#endif
	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;
	}
	device_remove_file(&debounce_device, &dev_attr_debounce_delay);
	device_remove_file(&debounce_device, &dev_attr_settle_time);
	device_remove_file(&debounce_device, &dev_attr_poll_time);
	device_remove_file(&debounce_device, &dev_attr_flags);
	device_unregister(&debounce_device);
}

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	27
f7cb07b2 MG	28	static ssize_t show_debounce_delay(struct device dev, struct device_attribute attr, char *buf)
	29	{
	30	if (!gpio_evmi)
	31	return -ENODEV;
	32
	33	return snprintf(buf, PAGE_SIZE, "%ld\n", (gpio_evmi->debounce_delay.tv.nsec / NSEC_PER_MSEC));
	34	}
	35
	36	static void set_debounce_delay(long delay)
	37	{
	38	if (gpio_evmi->debounce_delay.tv.nsec != delay * NSEC_PER_MSEC) {
	39	printk(KERN_INFO PREFIX "Changing debounce_delay\n");
	40	gpio_evmi->debounce_delay.tv.nsec = delay * NSEC_PER_MSEC;
	41	debounce_delay = delay;
	42	printk(KERN_INFO PREFIX "debounce_delay: %u\n", gpio_evmi->debounce_delay.tv.nsec);
	43	}
	44
	45	if (gpio_evmi->debounce_delay.tv.nsec != 0) {
	46	if (!(gpio_evmi->flags & GPIOKPF_DEBOUNCE)) {
	47	printk(KERN_INFO PREFIX "Activating debounce\n");
	48	gpio_evmi->flags \|= GPIOKPF_DEBOUNCE;
	49	}
	50	} else {
	51	if (gpio_evmi->flags & GPIOKPF_DEBOUNCE) {
	52	printk(KERN_INFO PREFIX "Deactivating debounce\n");
	53	gpio_evmi->flags &= ~GPIOKPF_DEBOUNCE;
	54	}
	55	}
	56	}
	57
	58	static ssize_t store_debounce_delay(struct device dev, struct device_attribute attr, const char *buf, size_t count)
	59	{
	60	long int delay;
	61
	62	if (!gpio_evmi)
	63	return -ENODEV;
	64
	65	sscanf(buf, "%ld", &delay);
	66	set_debounce_delay(delay);
	67
	68	return strnlen(buf, PAGE_SIZE);
	69	}
	70
	71	static ssize_t show_settle_time(struct device dev, struct device_attribute attr, char *buf)
	72	{
	73	if (!gpio_evmi)
	74	return -ENODEV;
	75
	76	return snprintf(buf, PAGE_SIZE, "%ld\n", (gpio_evmi->settle_time.tv.nsec / NSEC_PER_USEC));
	77	}
	78
	79	static ssize_t store_settle_time(struct device dev, struct device_attribute attr, const char *buf, size_t count)
	80	{
	81	long int delay;
	82
	83	if (!gpio_evmi)
	84	return -ENODEV;
	85
	86	sscanf(buf, "%ld", &delay);
	87	gpio_evmi->settle_time.tv.nsec = delay * NSEC_PER_USEC;
	88
	89	return strnlen(buf, PAGE_SIZE);
	90	}
	91
92	static ssize_t show_poll_time(struct device dev, struct device_attribute attr, char *buf)
93	{
94	if (!gpio_evmi)
95	return -ENODEV;
96
97	return snprintf(buf, PAGE_SIZE, "%ld\n", (gpio_evmi->poll_time.tv.nsec / NSEC_PER_MSEC));
98	}
99
100	static ssize_t store_poll_time(struct device dev, struct device_attribute attr, const char *buf, size_t count)
101	{
102	long int delay;
103
104	if (!gpio_evmi)
105	return -ENODEV;
106
107	sscanf(buf, "%ld", &delay);
108	gpio_evmi->poll_time.tv.nsec = delay * NSEC_PER_MSEC;
109
110	return strnlen(buf, PAGE_SIZE);
111	}
112
113	static ssize_t show_flags(struct device dev, struct device_attribute attr, char *buf)
114	{
115	if (!gpio_evmi)
116	return -ENODEV;
117
118	return snprintf(buf, PAGE_SIZE, "0x%x\n", gpio_evmi->flags);
119	}
120
121	static ssize_t store_flags(struct device dev, struct device_attribute attr, const char *buf, size_t count)
122	{
123	unsigned flags;
124
125	if (!gpio_evmi)
126	return -ENODEV;
127
128	sscanf(buf, "0x%x", &flags);
129	gpio_evmi->flags = flags;
130
131	return strnlen(buf, PAGE_SIZE);
132	}
133
134	static DEVICE_ATTR(debounce_delay, (S_IRUGO \| S_IWUGO), &show_debounce_delay, store_debounce_delay);
135	static DEVICE_ATTR(settle_time, (S_IRUGO \| S_IWUGO), &show_settle_time, store_settle_time);
136	static DEVICE_ATTR(poll_time, (S_IRUGO \| S_IWUGO), &show_poll_time, store_poll_time);
137	static DEVICE_ATTR(flags, (S_IRUGO \| S_IWUGO), &show_flags, store_flags);
138
139	static void debounce_release(struct device *dev)
140	{
141	}
142
143	static struct device debounce_device = {
144	.init_name = "debounce",
145	.release = debounce_release,
146	};
147
b422e333 MG	148	static int __init debounce_init(void)
b422e333 MG	149	{
d1ff9643 MG	150	struct device *event_dev = NULL;
	151	struct gpio_event_platform_data *gpio_epd;
	152	struct gpio_event_info *gpio_ei;
f7cb07b2	153	int err = 0;
d1ff9643	154
ab5ed215	155	printk(KERN_INFO PREFIX "Searching for " GPIO_EVENT_DEV_NAME "...\n");
d1ff9643 MG	156
	157	event_dev = device_find_child(&platform_bus, GPIO_EVENT_DEV_NAME, find_ms2_dev);
	158	if (event_dev == NULL)
	159	return -ENODEV;
	160
	161	gpio_epd = (struct gpio_event_platform_data*)event_dev->platform_data;
ab5ed215	162	printk(KERN_INFO PREFIX "And there is a %s connected...\n", gpio_epd->name);
d1ff9643 MG	163	if (strcmp(gpio_epd->name, "sholes-keypad"))
	164	return -ENODEV;
	165
	166	gpio_ei = (struct gpio_event_info*)gpio_epd->info[0];
	167	gpio_evmi = container_of(gpio_ei, struct gpio_event_matrix_info, info);
	168
f7cb07b2 MG	169	err = device_register(&debounce_device);
	170	if (err) {
	171	return err;
	172	}
	173
	174	err = device_create_file(&debounce_device, &dev_attr_debounce_delay);
	175	err = device_create_file(&debounce_device, &dev_attr_settle_time);
	176	err = device_create_file(&debounce_device, &dev_attr_poll_time);
	177	err = device_create_file(&debounce_device, &dev_attr_flags);
	178
ab5ed215 MG	179	printk(KERN_INFO PREFIX "settle_time: %u\n", gpio_evmi->settle_time.tv.nsec);
	180	printk(KERN_INFO PREFIX "poll_time: %u\n", gpio_evmi->poll_time.tv.nsec);
	181	printk(KERN_INFO PREFIX "debounce_delay: %u\n", gpio_evmi->debounce_delay.tv.nsec);
	182	printk(KERN_INFO PREFIX "flags: 0x%x\n", gpio_evmi->flags);
20bf1c9e	183
bb65757a MG	184	old_debounce_delay = gpio_evmi->debounce_delay;
	185	old_settle_time = gpio_evmi->settle_time;
	186	old_poll_time = gpio_evmi->poll_time;
	187	old_flags = gpio_evmi->flags;
1e65c113	188
f7cb07b2	189	set_debounce_delay(debounce_delay);
bb65757a MG	190	#if 0
	191	gpio_evmi->flags &= ~GPIOKPF_REMOVE_SOME_PHANTOM_KEYS;
	192	#endif
a4838b14 MG	193	printk(KERN_INFO PREFIX "flags: 0x%x\n", gpio_evmi->flags);
a4838b14 MG	194
b422e333 MG	195	return 0;
	196	}
	197
	198	static void __exit debounce_exit(void)
	199	{
1e65c113	200	if (gpio_evmi) {
bb65757a	201	if (gpio_evmi->debounce_delay.tv.nsec != old_debounce_delay.tv.nsec) {
1e65c113	202	printk(KERN_INFO PREFIX "Restoring debounce_delay\n");
bb65757a	203	gpio_evmi->debounce_delay = old_debounce_delay;
1e65c113 MG	204	printk(KERN_INFO PREFIX "debounce_delay: %u\n", gpio_evmi->debounce_delay.tv.nsec);
1e65c113 MG	205	}
a4838b14 MG	206	if (gpio_evmi->flags != old_flags) {
	207	printk(KERN_INFO PREFIX "Restoring flags\n");
	208	gpio_evmi->flags = old_flags;
	209	printk(KERN_INFO PREFIX "flags: 0x%x\n", gpio_evmi->flags);
	210	}
bb65757a MG	211	gpio_evmi->settle_time = old_settle_time;
bb65757a MG	212	gpio_evmi->poll_time = old_poll_time;
1e65c113	213	}
f7cb07b2 MG	214	device_remove_file(&debounce_device, &dev_attr_debounce_delay);
	215	device_remove_file(&debounce_device, &dev_attr_settle_time);
	216	device_remove_file(&debounce_device, &dev_attr_poll_time);
	217	device_remove_file(&debounce_device, &dev_attr_flags);
	218	device_unregister(&debounce_device);
b422e333 MG	219	}
	220
	221	module_init(debounce_init);
	222	module_exit(debounce_exit);
	223
	224	MODULE_LICENSE("GPL");
	225	MODULE_AUTHOR("Michael Gernoth <michael@gernoth.net>");