2 * Button Hotplug driver
4 * Copyright (C) 2008 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@openwrt.org>
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>
26 #define DRV_NAME "button-hotplug"
27 #define DRV_VERSION "0.3.0"
28 #define DRV_DESC "Button Hotplug driver"
30 #define BH_SKB_SIZE 2048
32 #define BH_BTN_MIN BTN_0
33 #define BH_BTN_MAX BTN_9
35 #define BH_BTN_COUNT (BH_BTN_MAX - BH_BTN_MIN + 1)
37 #define PFX DRV_NAME ": "
42 #define BH_DBG(fmt, args...) printk(KERN_DEBUG "%s" fmt, ##args )
44 #define BH_DBG(fmt, args...) do {} while (0)
47 #define BH_ERR(fmt, args...) printk(KERN_ERR "%s" fmt, ##args )
50 unsigned long seen[BH_BTN_COUNT];
51 struct input_handle handle;
60 struct work_struct work;
63 extern struct sock *uevent_sock;
64 extern u64 uevent_next_seqnum(void);
66 static char *button_names[BH_BTN_COUNT] = {
67 "BTN_0", "BTN_1", "BTN_2", "BTN_3", "BTN_4",
68 "BTN_5", "BTN_6", "BTN_7", "BTN_8", "BTN_9"
71 /* -------------------------------------------------------------------------*/
73 static int bh_event_add_var(struct bh_event *event, int argv,
74 const char *format, ...)
84 va_start(args, format);
85 len = vsnprintf(buf, sizeof(buf), format, args);
88 if (len >= sizeof(buf)) {
89 BH_ERR("buffer size too small\n");
94 s = skb_put(event->skb, len + 1);
97 BH_DBG("added variable '%s'\n", s);
102 static int button_hotplug_fill_event(struct bh_event *event)
106 ret = bh_event_add_var(event, 0, "HOME=%s", "/");
110 ret = bh_event_add_var(event, 0, "PATH=%s",
111 "/sbin:/bin:/usr/sbin:/usr/bin");
115 ret = bh_event_add_var(event, 0, "SUBSYSTEM=%s", "button");
119 ret = bh_event_add_var(event, 0, "ACTION=%s", event->action);
123 ret = bh_event_add_var(event, 0, "BUTTON=%s", event->name);
127 ret = bh_event_add_var(event, 0, "SEEN=%ld", event->seen);
131 ret = bh_event_add_var(event, 0, "SEQNUM=%llu", uevent_next_seqnum());
136 static void button_hotplug_work(struct work_struct *work)
138 struct bh_event *event = container_of(work, struct bh_event, work);
144 event->skb = alloc_skb(BH_SKB_SIZE, GFP_KERNEL);
148 ret = bh_event_add_var(event, 0, "%s@", event->action);
152 ret = button_hotplug_fill_event(event);
156 NETLINK_CB(event->skb).dst_group = 1;
157 netlink_broadcast(uevent_sock, event->skb, 0, 1, GFP_KERNEL);
161 BH_ERR("work error %d\n", ret);
162 kfree_skb(event->skb);
168 static int button_hotplug_create_event(char *name, unsigned long seen,
171 struct bh_event *event;
173 BH_DBG("create event, name=%s, seen=%lu, pressed=%d\n",
174 name, seen, pressed);
176 event = kzalloc(sizeof(*event), GFP_KERNEL);
182 event->action = pressed ? "pressed" : "released";
184 INIT_WORK(&event->work, (void *)(void *)button_hotplug_work);
185 schedule_work(&event->work);
190 /* -------------------------------------------------------------------------*/
192 #ifdef CONFIG_HOTPLUG
193 static void button_hotplug_event(struct input_handle *handle,
194 unsigned int type, unsigned int code, int value)
196 struct bh_priv *priv = handle->private;
197 unsigned long seen = jiffies;
200 BH_DBG("event type=%u, code=%u, value=%d\n", type, code, value);
205 if (code < BH_BTN_MIN || code > BH_BTN_MAX)
208 btn = code - BH_BTN_MIN;
209 button_hotplug_create_event(button_names[btn],
210 (seen - priv->seen[btn]) / HZ, value);
211 priv->seen[btn] = seen;
214 static void button_hotplug_event(struct input_handle *handle,
215 unsigned int type, unsigned int code, int value)
218 #endif /* CONFIG_HOTPLUG */
220 static int button_hotplug_connect(struct input_handler *handler,
221 struct input_dev *dev, const struct input_device_id *id)
223 struct bh_priv *priv;
227 for (i = BH_BTN_MIN; i <= BH_BTN_MAX; i++)
228 if (test_bit(i, dev->keybit))
234 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
238 priv->handle.private = priv;
239 priv->handle.dev = dev;
240 priv->handle.handler = handler;
241 priv->handle.name = DRV_NAME;
243 ret = input_register_handle(&priv->handle);
247 ret = input_open_device(&priv->handle);
249 goto err_unregister_handle;
251 BH_DBG("connected to %s\n", dev->name);
255 err_unregister_handle:
256 input_unregister_handle(&priv->handle);
263 static void button_hotplug_disconnect(struct input_handle *handle)
265 struct bh_priv *priv = handle->private;
267 input_close_device(handle);
268 input_unregister_handle(handle);
273 static const struct input_device_id button_hotplug_ids[] = {
275 .flags = INPUT_DEVICE_ID_MATCH_EVBIT,
276 .evbit = { BIT_MASK(EV_KEY) },
279 /* Terminating entry */
283 MODULE_DEVICE_TABLE(input, button_hotplug_ids);
285 static struct input_handler button_hotplug_handler = {
286 .event = button_hotplug_event,
287 .connect = button_hotplug_connect,
288 .disconnect = button_hotplug_disconnect,
290 .id_table = button_hotplug_ids,
293 /* -------------------------------------------------------------------------*/
295 static int __init button_hotplug_init(void)
299 printk(KERN_INFO DRV_DESC " version " DRV_VERSION "\n");
300 ret = input_register_handler(&button_hotplug_handler);
302 BH_ERR("unable to register input handler\n");
306 module_init(button_hotplug_init);
308 static void __exit button_hotplug_exit(void)
310 input_unregister_handler(&button_hotplug_handler);
312 module_exit(button_hotplug_exit);
314 MODULE_DESCRIPTION(DRV_DESC);
315 MODULE_VERSION(DRV_VERSION);
316 MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
317 MODULE_LICENSE("GPL v2");