2 * Button Hotplug driver
4 * Copyright (C) 2008-2010 Gabor Juhos <juhosg@openwrt.org>
6 * Based on the diag.c - GPIO interface driver for Broadcom boards
7 * Copyright (C) 2006 Mike Baker <mbm@openwrt.org>,
8 * Copyright (C) 2006-2007 Felix Fietkau <nbd@nbd.name>
9 * Copyright (C) 2008 Andy Boyett <agb@openwrt.org>
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License version 2 as published
13 * by the Free Software Foundation.
16 #include <linux/module.h>
17 #include <linux/version.h>
18 #include <linux/kmod.h>
19 #include <linux/input.h>
21 #include <linux/workqueue.h>
22 #include <linux/skbuff.h>
23 #include <linux/netlink.h>
24 #include <linux/kobject.h>
26 #define DRV_NAME "button-hotplug"
27 #define DRV_VERSION "0.4.1"
28 #define DRV_DESC "Button Hotplug driver"
30 #define BH_SKB_SIZE 2048
32 #define PFX DRV_NAME ": "
37 #define BH_DBG(fmt, args...) printk(KERN_DEBUG "%s: " fmt, DRV_NAME, ##args )
39 #define BH_DBG(fmt, args...) do {} while (0)
42 #define BH_ERR(fmt, args...) printk(KERN_ERR "%s: " fmt, DRV_NAME, ##args )
45 #define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG))
50 struct input_handle handle;
59 struct work_struct work;
67 extern u64 uevent_next_seqnum(void);
69 #define BH_MAP(_code, _name) \
75 static struct bh_map button_map[] = {
76 BH_MAP(BTN_0, "BTN_0"),
77 BH_MAP(BTN_1, "BTN_1"),
78 BH_MAP(BTN_2, "BTN_2"),
79 BH_MAP(BTN_3, "BTN_3"),
80 BH_MAP(BTN_4, "BTN_4"),
81 BH_MAP(BTN_5, "BTN_5"),
82 BH_MAP(BTN_6, "BTN_6"),
83 BH_MAP(BTN_7, "BTN_7"),
84 BH_MAP(BTN_8, "BTN_8"),
85 BH_MAP(BTN_9, "BTN_9"),
86 BH_MAP(KEY_RESTART, "reset"),
87 BH_MAP(KEY_POWER, "power"),
88 BH_MAP(KEY_RFKILL, "rfkill"),
89 BH_MAP(KEY_WPS_BUTTON, "wps"),
90 BH_MAP(KEY_WIMAX, "wwan"),
93 /* -------------------------------------------------------------------------*/
95 static int bh_event_add_var(struct bh_event *event, int argv,
96 const char *format, ...)
106 va_start(args, format);
107 len = vsnprintf(buf, sizeof(buf), format, args);
110 if (len >= sizeof(buf)) {
111 BH_ERR("buffer size too small\n");
116 s = skb_put(event->skb, len + 1);
119 BH_DBG("added variable '%s'\n", s);
124 static int button_hotplug_fill_event(struct bh_event *event)
128 ret = bh_event_add_var(event, 0, "HOME=%s", "/");
132 ret = bh_event_add_var(event, 0, "PATH=%s",
133 "/sbin:/bin:/usr/sbin:/usr/bin");
137 ret = bh_event_add_var(event, 0, "SUBSYSTEM=%s", "button");
141 ret = bh_event_add_var(event, 0, "ACTION=%s", event->action);
145 ret = bh_event_add_var(event, 0, "BUTTON=%s", event->name);
149 ret = bh_event_add_var(event, 0, "SEEN=%ld", event->seen);
153 ret = bh_event_add_var(event, 0, "SEQNUM=%llu", uevent_next_seqnum());
158 static void button_hotplug_work(struct work_struct *work)
160 struct bh_event *event = container_of(work, struct bh_event, work);
163 event->skb = alloc_skb(BH_SKB_SIZE, GFP_KERNEL);
167 ret = bh_event_add_var(event, 0, "%s@", event->action);
171 ret = button_hotplug_fill_event(event);
175 NETLINK_CB(event->skb).dst_group = 1;
176 broadcast_uevent(event->skb, 0, 1, GFP_KERNEL);
180 BH_ERR("work error %d\n", ret);
181 kfree_skb(event->skb);
187 static int button_hotplug_create_event(const char *name, unsigned long seen,
190 struct bh_event *event;
192 BH_DBG("create event, name=%s, seen=%lu, pressed=%d\n",
193 name, seen, pressed);
195 event = kzalloc(sizeof(*event), GFP_KERNEL);
201 event->action = pressed ? "pressed" : "released";
203 INIT_WORK(&event->work, (void *)(void *)button_hotplug_work);
204 schedule_work(&event->work);
209 /* -------------------------------------------------------------------------*/
211 static int button_get_index(unsigned int code)
215 for (i = 0; i < ARRAY_SIZE(button_map); i++)
216 if (button_map[i].code == code)
221 static void button_hotplug_event(struct input_handle *handle,
222 unsigned int type, unsigned int code, int value)
224 struct bh_priv *priv = handle->private;
225 unsigned long seen = jiffies;
228 BH_DBG("event type=%u, code=%u, value=%d\n", type, code, value);
233 btn = button_get_index(code);
237 button_hotplug_create_event(button_map[btn].name,
238 (seen - priv->seen[btn]) / HZ, value);
239 priv->seen[btn] = seen;
242 static int button_hotplug_connect(struct input_handler *handler,
243 struct input_dev *dev, const struct input_device_id *id)
245 struct bh_priv *priv;
249 for (i = 0; i < ARRAY_SIZE(button_map); i++)
250 if (test_bit(button_map[i].code, dev->keybit))
253 if (i == ARRAY_SIZE(button_map))
256 priv = kzalloc(sizeof(*priv) +
257 (sizeof(unsigned long) * ARRAY_SIZE(button_map)),
262 priv->seen = (unsigned long *) &priv[1];
263 priv->handle.private = priv;
264 priv->handle.dev = dev;
265 priv->handle.handler = handler;
266 priv->handle.name = DRV_NAME;
268 ret = input_register_handle(&priv->handle);
272 ret = input_open_device(&priv->handle);
274 goto err_unregister_handle;
276 BH_DBG("connected to %s\n", dev->name);
280 err_unregister_handle:
281 input_unregister_handle(&priv->handle);
288 static void button_hotplug_disconnect(struct input_handle *handle)
290 struct bh_priv *priv = handle->private;
292 input_close_device(handle);
293 input_unregister_handle(handle);
298 static const struct input_device_id button_hotplug_ids[] = {
300 .flags = INPUT_DEVICE_ID_MATCH_EVBIT,
301 .evbit = { BIT_MASK(EV_KEY) },
304 /* Terminating entry */
308 MODULE_DEVICE_TABLE(input, button_hotplug_ids);
310 static struct input_handler button_hotplug_handler = {
311 .event = button_hotplug_event,
312 .connect = button_hotplug_connect,
313 .disconnect = button_hotplug_disconnect,
315 .id_table = button_hotplug_ids,
318 /* -------------------------------------------------------------------------*/
320 static int __init button_hotplug_init(void)
324 printk(KERN_INFO DRV_DESC " version " DRV_VERSION "\n");
325 ret = input_register_handler(&button_hotplug_handler);
327 BH_ERR("unable to register input handler\n");
331 module_init(button_hotplug_init);
333 static void __exit button_hotplug_exit(void)
335 input_unregister_handler(&button_hotplug_handler);
337 module_exit(button_hotplug_exit);
339 MODULE_DESCRIPTION(DRV_DESC);
340 MODULE_VERSION(DRV_VERSION);
341 MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
342 MODULE_LICENSE("GPL v2");