/* * Button Hotplug driver * * Copyright (C) 2008 Gabor Juhos * * Based on the diag.c - GPIO interface driver for Broadcom boards * Copyright (C) 2006 Mike Baker , * Copyright (C) 2006-2007 Felix Fietkau * Copyright (C) 2008 Andy Boyett * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published * by the Free Software Foundation. */ #include #include #include #include #include #include #include #include #define DRV_NAME "button-hotplug" #define DRV_VERSION "0.3.1" #define DRV_DESC "Button Hotplug driver" #define BH_SKB_SIZE 2048 #define BH_BTN_MIN BTN_0 #define BH_BTN_MAX BTN_9 #define BH_BTN_COUNT (BH_BTN_MAX - BH_BTN_MIN + 1) #define PFX DRV_NAME ": " #undef BH_DEBUG #ifdef BH_DEBUG #define BH_DBG(fmt, args...) printk(KERN_DEBUG "%s: " fmt, DRV_NAME, ##args ) #else #define BH_DBG(fmt, args...) do {} while (0) #endif #define BH_ERR(fmt, args...) printk(KERN_ERR "%s: " fmt, DRV_NAME, ##args ) #ifndef BIT_MASK #define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG)) #endif struct bh_priv { unsigned long seen[BH_BTN_COUNT]; struct input_handle handle; }; struct bh_event { char *name; char *action; unsigned long seen; struct sk_buff *skb; struct work_struct work; }; extern struct sock *uevent_sock; extern u64 uevent_next_seqnum(void); static char *button_names[BH_BTN_COUNT] = { "BTN_0", "BTN_1", "BTN_2", "BTN_3", "BTN_4", "BTN_5", "BTN_6", "BTN_7", "BTN_8", "BTN_9" }; /* -------------------------------------------------------------------------*/ static int bh_event_add_var(struct bh_event *event, int argv, const char *format, ...) { static char buf[128]; char *s; va_list args; int len; if (argv) return 0; va_start(args, format); len = vsnprintf(buf, sizeof(buf), format, args); va_end(args); if (len >= sizeof(buf)) { BH_ERR("buffer size too small\n"); WARN_ON(1); return -ENOMEM; } s = skb_put(event->skb, len + 1); strcpy(s, buf); BH_DBG("added variable '%s'\n", s); return 0; } static int button_hotplug_fill_event(struct bh_event *event) { int ret; ret = bh_event_add_var(event, 0, "HOME=%s", "/"); if (ret) return ret; ret = bh_event_add_var(event, 0, "PATH=%s", "/sbin:/bin:/usr/sbin:/usr/bin"); if (ret) return ret; ret = bh_event_add_var(event, 0, "SUBSYSTEM=%s", "button"); if (ret) return ret; ret = bh_event_add_var(event, 0, "ACTION=%s", event->action); if (ret) return ret; ret = bh_event_add_var(event, 0, "BUTTON=%s", event->name); if (ret) return ret; ret = bh_event_add_var(event, 0, "SEEN=%ld", event->seen); if (ret) return ret; ret = bh_event_add_var(event, 0, "SEQNUM=%llu", uevent_next_seqnum()); return ret; } static void button_hotplug_work(struct work_struct *work) { struct bh_event *event = container_of(work, struct bh_event, work); int ret = 0; if (!uevent_sock) goto out_free_event; event->skb = alloc_skb(BH_SKB_SIZE, GFP_KERNEL); if (!event->skb) goto out_free_event; ret = bh_event_add_var(event, 0, "%s@", event->action); if (ret) goto out_free_skb; ret = button_hotplug_fill_event(event); if (ret) goto out_free_skb; NETLINK_CB(event->skb).dst_group = 1; netlink_broadcast(uevent_sock, event->skb, 0, 1, GFP_KERNEL); out_free_skb: if (ret) { BH_ERR("work error %d\n", ret); kfree_skb(event->skb); } out_free_event: kfree(event); } static int button_hotplug_create_event(char *name, unsigned long seen, int pressed) { struct bh_event *event; BH_DBG("create event, name=%s, seen=%lu, pressed=%d\n", name, seen, pressed); event = kzalloc(sizeof(*event), GFP_KERNEL); if (!event) return -ENOMEM; event->name = name; event->seen = seen; event->action = pressed ? "pressed" : "released"; INIT_WORK(&event->work, (void *)(void *)button_hotplug_work); schedule_work(&event->work); return 0; } /* -------------------------------------------------------------------------*/ #ifdef CONFIG_HOTPLUG static void button_hotplug_event(struct input_handle *handle, unsigned int type, unsigned int code, int value) { struct bh_priv *priv = handle->private; unsigned long seen = jiffies; unsigned int btn; BH_DBG("event type=%u, code=%u, value=%d\n", type, code, value); if (type != EV_KEY) return; if (code < BH_BTN_MIN || code > BH_BTN_MAX) return; btn = code - BH_BTN_MIN; button_hotplug_create_event(button_names[btn], (seen - priv->seen[btn]) / HZ, value); priv->seen[btn] = seen; } #else static void button_hotplug_event(struct input_handle *handle, unsigned int type, unsigned int code, int value) { } #endif /* CONFIG_HOTPLUG */ static int button_hotplug_connect(struct input_handler *handler, struct input_dev *dev, const struct input_device_id *id) { struct bh_priv *priv; int ret; int i; for (i = BH_BTN_MIN; i <= BH_BTN_MAX; i++) if (test_bit(i, dev->keybit)) break; if (i > BH_BTN_MAX) return -ENODEV; priv = kzalloc(sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; priv->handle.private = priv; priv->handle.dev = dev; priv->handle.handler = handler; priv->handle.name = DRV_NAME; ret = input_register_handle(&priv->handle); if (ret) goto err_free_priv; ret = input_open_device(&priv->handle); if (ret) goto err_unregister_handle; BH_DBG("connected to %s\n", dev->name); return 0; err_unregister_handle: input_unregister_handle(&priv->handle); err_free_priv: kfree(priv); return ret; } static void button_hotplug_disconnect(struct input_handle *handle) { struct bh_priv *priv = handle->private; input_close_device(handle); input_unregister_handle(handle); kfree(priv); } static const struct input_device_id button_hotplug_ids[] = { { .flags = INPUT_DEVICE_ID_MATCH_EVBIT, .evbit = { BIT_MASK(EV_KEY) }, }, { /* Terminating entry */ }, }; MODULE_DEVICE_TABLE(input, button_hotplug_ids); static struct input_handler button_hotplug_handler = { .event = button_hotplug_event, .connect = button_hotplug_connect, .disconnect = button_hotplug_disconnect, .name = DRV_NAME, .id_table = button_hotplug_ids, }; /* -------------------------------------------------------------------------*/ static int __init button_hotplug_init(void) { int ret; printk(KERN_INFO DRV_DESC " version " DRV_VERSION "\n"); ret = input_register_handler(&button_hotplug_handler); if (ret) BH_ERR("unable to register input handler\n"); return ret; } module_init(button_hotplug_init); static void __exit button_hotplug_exit(void) { input_unregister_handler(&button_hotplug_handler); } module_exit(button_hotplug_exit); MODULE_DESCRIPTION(DRV_DESC); MODULE_VERSION(DRV_VERSION); MODULE_AUTHOR("Gabor Juhos "); MODULE_LICENSE("GPL v2");