/* **************************************************************************** * (C) 2006 - Cambridge University **************************************************************************** * * File: gnttab.c * Author: Steven Smith (sos22@cam.ac.uk) * Changes: Grzegorz Milos (gm281@cam.ac.uk) * * Date: July 2006 * * Environment: Xen Minimal OS * Description: Simple grant tables implementation. About as stupid as it's * possible to be and still work. * **************************************************************************** */ #include #include #include #include #define NR_RESERVED_ENTRIES 8 /* NR_GRANT_FRAMES must be less than or equal to that configured in Xen */ #ifdef __ia64__ #define NR_GRANT_FRAMES 1 #else #define NR_GRANT_FRAMES 4 #endif #define NR_GRANT_ENTRIES (NR_GRANT_FRAMES * PAGE_SIZE / sizeof(grant_entry_t)) static grant_entry_t *gnttab_table; static grant_ref_t gnttab_list[NR_GRANT_ENTRIES]; #ifdef GNT_DEBUG static char inuse[NR_GRANT_ENTRIES]; #endif static __DECLARE_SEMAPHORE_GENERIC(gnttab_sem, 0); static void put_free_entry(grant_ref_t ref) { unsigned long flags; local_irq_save(flags); #ifdef GNT_DEBUG BUG_ON(!inuse[ref]); inuse[ref] = 0; #endif gnttab_list[ref] = gnttab_list[0]; gnttab_list[0] = ref; local_irq_restore(flags); up(&gnttab_sem); } static grant_ref_t get_free_entry(void) { unsigned int ref; unsigned long flags; down(&gnttab_sem); local_irq_save(flags); ref = gnttab_list[0]; BUG_ON(ref < NR_RESERVED_ENTRIES || ref >= NR_GRANT_ENTRIES); gnttab_list[0] = gnttab_list[ref]; #ifdef GNT_DEBUG BUG_ON(inuse[ref]); inuse[ref] = 1; #endif local_irq_restore(flags); return ref; } grant_ref_t gnttab_grant_access(domid_t domid, unsigned long frame, int readonly) { grant_ref_t ref; ref = get_free_entry(); gnttab_table[ref].frame = frame; gnttab_table[ref].domid = domid; wmb(); readonly *= GTF_readonly; gnttab_table[ref].flags = GTF_permit_access | readonly; return ref; } grant_ref_t gnttab_grant_transfer(domid_t domid, unsigned long pfn) { grant_ref_t ref; ref = get_free_entry(); gnttab_table[ref].frame = pfn; gnttab_table[ref].domid = domid; wmb(); gnttab_table[ref].flags = GTF_accept_transfer; return ref; } int gnttab_end_access(grant_ref_t ref) { u16 flags, nflags; BUG_ON(ref >= NR_GRANT_ENTRIES || ref < NR_RESERVED_ENTRIES); nflags = gnttab_table[ref].flags; do { if ((flags = nflags) & (GTF_reading|GTF_writing)) { printk("WARNING: g.e. still in use! (%x)\n", flags); return 0; } } while ((nflags = synch_cmpxchg(&gnttab_table[ref].flags, flags, 0)) != flags); put_free_entry(ref); return 1; } unsigned long gnttab_end_transfer(grant_ref_t ref) { unsigned long frame; u16 flags; BUG_ON(ref >= NR_GRANT_ENTRIES || ref < NR_RESERVED_ENTRIES); while (!((flags = gnttab_table[ref].flags) & GTF_transfer_committed)) { if (synch_cmpxchg(&gnttab_table[ref].flags, flags, 0) == flags) { printk("Release unused transfer grant.\n"); put_free_entry(ref); return 0; } } /* If a transfer is in progress then wait until it is completed. */ while (!(flags & GTF_transfer_completed)) { flags = gnttab_table[ref].flags; } /* Read the frame number /after/ reading completion status. */ rmb(); frame = gnttab_table[ref].frame; put_free_entry(ref); return frame; } grant_ref_t gnttab_alloc_and_grant(void **map) { unsigned long mfn; grant_ref_t gref; *map = (void *)alloc_page(); mfn = virt_to_mfn(*map); gref = gnttab_grant_access(0, mfn, 0); return gref; } static const char * const gnttabop_error_msgs[] = GNTTABOP_error_msgs; const char * gnttabop_error(int16_t status) { status = -status; if (status < 0 || status >= ARRAY_SIZE(gnttabop_error_msgs)) return "bad status"; else return gnttabop_error_msgs[status]; } void init_gnttab(void) { struct gnttab_setup_table setup; unsigned long frames[NR_GRANT_FRAMES]; int i; #ifdef GNT_DEBUG memset(inuse, 1, sizeof(inuse)); #endif for (i = NR_RESERVED_ENTRIES; i < NR_GRANT_ENTRIES; i++) put_free_entry(i); setup.dom = DOMID_SELF; setup.nr_frames = NR_GRANT_FRAMES; set_xen_guest_handle(setup.frame_list, frames); HYPERVISOR_grant_table_op(GNTTABOP_setup_table, &setup, 1); gnttab_table = map_frames(frames, NR_GRANT_FRAMES); printk("gnttab_table mapped at %p.\n", gnttab_table); } void fini_gnttab(void) { struct gnttab_setup_table setup; setup.dom = DOMID_SELF; setup.nr_frames = 0; HYPERVISOR_grant_table_op(GNTTABOP_setup_table, &setup, 1); } n15' href='#n15'>15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 
/*
 *  Button Hotplug driver
 *
 *  Copyright (C) 2008-2010 Gabor Juhos <juhosg@openwrt.org>
 *
 *  Based on the diag.c - GPIO interface driver for Broadcom boards
 *    Copyright (C) 2006 Mike Baker <mbm@openwrt.org>,
 *    Copyright (C) 2006-2007 Felix Fietkau <nbd@nbd.name>
 *    Copyright (C) 2008 Andy Boyett <agb@openwrt.org>
 *
 *  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 <linux/module.h>
#include <linux/version.h>
#include <linux/kmod.h>
#include <linux/input.h>

#include <linux/workqueue.h>
#include <linux/skbuff.h>
#include <linux/netlink.h>
#include <linux/kobject.h>

#define DRV_NAME	"button-hotplug"
#define DRV_VERSION	"0.4.1"
#define DRV_DESC	"Button Hotplug driver"

#define BH_SKB_SIZE	2048

#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;
	struct input_handle	handle;
};

struct bh_event {
	const char		*name;
	char			*action;
	unsigned long		seen;

	struct sk_buff		*skb;
	struct work_struct	work;
};

struct bh_map {
	unsigned int	code;
	const char	*name;
};

extern u64 uevent_next_seqnum(void);

#define BH_MAP(_code, _name)		\
	{				\
		.code = (_code),	\
		.name = (_name),	\
	}

static struct bh_map button_map[] = {
	BH_MAP(BTN_0,		"BTN_0"),
	BH_MAP(BTN_1,		"BTN_1"),
	BH_MAP(BTN_2,		"BTN_2"),
	BH_MAP(BTN_3,		"BTN_3"),
	BH_MAP(BTN_4,		"BTN_4"),
	BH_MAP(BTN_5,		"BTN_5"),
	BH_MAP(BTN_6,		"BTN_6"),
	BH_MAP(BTN_7,		"BTN_7"),
	BH_MAP(BTN_8,		"BTN_8"),
	BH_MAP(BTN_9,		"BTN_9"),
	BH_MAP(KEY_RESTART,	"reset"),
	BH_MAP(KEY_POWER,	"power"),
	BH_MAP(KEY_POWER2,	"reboot"),
	BH_MAP(KEY_RFKILL,	"rfkill"),
	BH_MAP(KEY_WPS_BUTTON,	"wps"),
	BH_MAP(KEY_WIMAX,	"wwan"),
};

/* -------------------------------------------------------------------------*/

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;

	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;
	broadcast_uevent(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(const 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;
}

/* -------------------------------------------------------------------------*/

static int button_get_index(unsigned int code)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(button_map); i++)
		if (button_map[i].code == code)
			return i;

	return -1;
}
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;
	int btn;

	BH_DBG("event type=%u, code=%u, value=%d\n", type, code, value);

	if (type != EV_KEY)
		return;

	btn = button_get_index(code);
	if (btn < 0)
		return;

	button_hotplug_create_event(button_map[btn].name,
			(seen - priv->seen[btn]) / HZ, value);
	priv->seen[btn] = seen;
}

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 = 0; i < ARRAY_SIZE(button_map); i++)
		if (test_bit(button_map[i].code, dev->keybit))
			break;

	if (i == ARRAY_SIZE(button_map))
		return -ENODEV;

	priv = kzalloc(sizeof(*priv) +
		       (sizeof(unsigned long) * ARRAY_SIZE(button_map)),
		       GFP_KERNEL);
	if (!priv)
		return -ENOMEM;

	priv->seen = (unsigned long *) &priv[1];
	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 <juhosg@openwrt.org>");
MODULE_LICENSE("GPL v2");
generated by cgit v1.2.3 (git 2.25.1) at 2026-02-12 04:02:14 +0000