xref: /dragonfly/sys/dev/misc/led/led.c (revision 0db87cb7)
1 /*-
2  * ----------------------------------------------------------------------------
3  * "THE BEER-WARE LICENSE" (Revision 42):
4  * <phk@FreeBSD.org> wrote this file.  As long as you retain this notice you
5  * can do whatever you want with this stuff. If we meet some day, and you think
6  * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
7  * ----------------------------------------------------------------------------
8  *
9  * $FreeBSD: head/sys/dev/led/led.c 247008 2013-02-19 19:25:50Z mav $
10  */
11 
12 #include <sys/param.h>
13 #include <sys/conf.h>
14 #include <sys/kernel.h>
15 #include <sys/systm.h>
16 #include <sys/limits.h>
17 #include <sys/malloc.h>
18 #include <sys/ctype.h>
19 #include <sys/sbuf.h>
20 #include <sys/queue.h>
21 #include <dev/misc/led/led.h>
22 #include <sys/uio.h>
23 #include <sys/device.h>
24 
25 struct ledsc {
26 	LIST_ENTRY(ledsc)	list;
27 	char			*name;
28 	void			*private;
29 	int			unit;
30 	led_t			*func;
31 	struct cdev *dev;
32 	struct sbuf		*spec;
33 	char			*str;
34 	char			*ptr;
35 	int			count;
36 	time_t			last_second;
37 };
38 
39 static struct unrhdr *led_unit;
40 static struct lock led_lock;
41 static struct lock led_lock2;
42 static LIST_HEAD(, ledsc) led_list = LIST_HEAD_INITIALIZER(led_list);
43 static struct callout led_ch;
44 static int blinkers = 0;
45 
46 static MALLOC_DEFINE(M_LED, "LED", "LED driver");
47 
48 static void
49 led_timeout(void *p)
50 {
51 	struct ledsc	*sc;
52 
53 	lockmgr(&led_lock, LK_EXCLUSIVE);
54 	LIST_FOREACH(sc, &led_list, list) {
55 		if (sc->ptr == NULL)
56 			continue;
57 		if (sc->count > 0) {
58 			sc->count--;
59 			continue;
60 		}
61 		if (*sc->ptr == '.') {
62 			sc->ptr = NULL;
63 			blinkers--;
64 			continue;
65 		} else if (*sc->ptr == 'U' || *sc->ptr == 'u') {
66 			if (sc->last_second == time_second)
67 				continue;
68 			sc->last_second = time_second;
69 			sc->func(sc->private, *sc->ptr == 'U');
70 		} else if (*sc->ptr >= 'a' && *sc->ptr <= 'j') {
71 			sc->func(sc->private, 0);
72 			sc->count = (*sc->ptr & 0xf) - 1;
73 		} else if (*sc->ptr >= 'A' && *sc->ptr <= 'J') {
74 			sc->func(sc->private, 1);
75 			sc->count = (*sc->ptr & 0xf) - 1;
76 		}
77 		sc->ptr++;
78 		if (*sc->ptr == '\0')
79 			sc->ptr = sc->str;
80 	}
81 	if (blinkers > 0)
82 		callout_reset(&led_ch, hz / 10, led_timeout, p);
83 	lockmgr(&led_lock, LK_RELEASE);
84 }
85 
86 static int
87 led_state(struct ledsc *sc, struct sbuf **sb, int state)
88 {
89 	struct sbuf *sb2 = NULL;
90 
91 	sb2 = sc->spec;
92 	sc->spec = *sb;
93 	if (*sb != NULL) {
94 		sc->str = sbuf_data(*sb);
95 		if (sc->ptr == NULL) {
96 			blinkers++;
97 			callout_reset(&led_ch, hz / 10, led_timeout, NULL);
98 		}
99 		sc->ptr = sc->str;
100 	} else {
101 		sc->str = NULL;
102 		if (sc->ptr != NULL)
103 			blinkers--;
104 		sc->ptr = NULL;
105 		sc->func(sc->private, state);
106 	}
107 	sc->count = 0;
108 	*sb = sb2;
109 	return(0);
110 }
111 
112 static int
113 led_parse(const char *s, struct sbuf **sb, int *state)
114 {
115 	int i, error;
116 
117 	/*
118 	 * Handle "on" and "off" immediately so people can flash really
119 	 * fast from userland if they want to
120 	 */
121 	if (*s == '0' || *s == '1') {
122 		*state = *s & 1;
123 		return (0);
124 	}
125 
126 	*state = 0;
127 	*sb = sbuf_new_auto();
128 	if (*sb == NULL)
129 		return (ENOMEM);
130 	switch(s[0]) {
131 		/*
132 		 * Flash, default is 100msec/100msec.
133 		 * 'f2' sets 200msec/200msec etc.
134 		 */
135 		case 'f':
136 			if (s[1] >= '1' && s[1] <= '9')
137 				i = s[1] - '1';
138 			else
139 				i = 0;
140 			sbuf_printf(*sb, "%c%c", 'A' + i, 'a' + i);
141 			break;
142 		/*
143 		 * Digits, flashes out numbers.
144 		 * 'd12' becomes -__________-_-______________________________
145 		 */
146 		case 'd':
147 			for(s++; *s; s++) {
148 				if (!isdigit(*s))
149 					continue;
150 				i = *s - '0';
151 				if (i == 0)
152 					i = 10;
153 				for (; i > 1; i--)
154 					sbuf_cat(*sb, "Aa");
155 				sbuf_cat(*sb, "Aj");
156 			}
157 			sbuf_cat(*sb, "jj");
158 			break;
159 		/*
160 		 * String, roll your own.
161 		 * 'a-j' gives "off" for n/10 sec.
162 		 * 'A-J' gives "on" for n/10 sec.
163 		 * no delay before repeat
164 		 * 'sAaAbBa' becomes _-_--__-
165 		 */
166 		case 's':
167 			for(s++; *s; s++) {
168 				if ((*s >= 'a' && *s <= 'j') ||
169 				    (*s >= 'A' && *s <= 'J') ||
170 				    *s == 'U' || *s <= 'u' ||
171 					*s == '.')
172 					sbuf_bcat(*sb, s, 1);
173 			}
174 			break;
175 		/*
176 		 * Morse.
177 		 * '.' becomes _-
178 		 * '-' becomes _---
179 		 * ' ' becomes __
180 		 * '\n' becomes ____
181 		 * 1sec pause between repeats
182 		 * '... --- ...' -> _-_-_-___---_---_---___-_-_-__________
183 		 */
184 		case 'm':
185 			for(s++; *s; s++) {
186 				if (*s == '.')
187 					sbuf_cat(*sb, "aA");
188 				else if (*s == '-')
189 					sbuf_cat(*sb, "aC");
190 				else if (*s == ' ')
191 					sbuf_cat(*sb, "b");
192 				else if (*s == '\n')
193 					sbuf_cat(*sb, "d");
194 			}
195 			sbuf_cat(*sb, "j");
196 			break;
197 		default:
198 			sbuf_delete(*sb);
199 			return (EINVAL);
200 	}
201 	error = sbuf_finish(*sb);
202 	if (error != 0 || sbuf_len(*sb) == 0) {
203 		*sb = NULL;
204 		return (error);
205 	}
206 	return (0);
207 }
208 
209 static int
210 led_open(struct dev_open_args *ap)
211 {
212 	return (0);
213 }
214 
215 static int
216 led_close(struct dev_close_args *ap)
217 {
218 	return (0);
219 }
220 
221 static int
222 led_write(struct dev_write_args *ap)
223 {
224 	struct uio *uio = ap->a_uio;
225 	cdev_t dev = ap->a_head.a_dev;
226 	struct ledsc	*sc;
227 	char *s;
228 	struct sbuf *sb = NULL;
229 	int error, state = 0;
230 
231 	if (uio->uio_resid > 512)
232 		return (EINVAL);
233 	s = kmalloc(uio->uio_resid + 1, M_DEVBUF, M_WAITOK);
234 	s[uio->uio_resid] = '\0';
235 	error = uiomove(s, uio->uio_resid, uio);
236 	if (error) {
237 		kfree(s, M_DEVBUF);
238 		return (error);
239 	}
240 	error = led_parse(s, &sb, &state);
241 	kfree(s, M_DEVBUF);
242 	if (error)
243 		return (error);
244 	lockmgr(&led_lock, LK_EXCLUSIVE);
245 	sc = dev->si_drv1;
246 	if (sc != NULL)
247 		error = led_state(sc, &sb, state);
248 	lockmgr(&led_lock, LK_RELEASE);
249 	if (sb != NULL)
250 		sbuf_delete(sb);
251 	return (error);
252 }
253 
254 int
255 led_set(char const *name, char const *cmd)
256 {
257 	struct ledsc	*sc;
258 	struct sbuf *sb = NULL;
259 	int error, state = 0;
260 
261 	error = led_parse(cmd, &sb, &state);
262 	if (error)
263 		return (error);
264 	lockmgr(&led_lock, LK_EXCLUSIVE);
265 	LIST_FOREACH(sc, &led_list, list) {
266 		if (strcmp(sc->name, name) == 0)
267 			break;
268 	}
269 	if (sc != NULL)
270 		error = led_state(sc, &sb, state);
271 	else
272 		error = ENOENT;
273 	lockmgr(&led_lock, LK_RELEASE);
274 	if (sb != NULL)
275 		sbuf_delete(sb);
276 	return (0);
277 }
278 
279 static struct dev_ops led_ops = {
280 	{ "LED", 0, 0 },
281 	.d_open =	led_open,
282 	.d_close =	led_close,
283 	.d_write =	led_write,
284 };
285 
286 struct cdev *
287 led_create(led_t *func, void *priv, char const *name)
288 {
289 
290 	return (led_create_state(func, priv, name, 0));
291 }
292 struct cdev *
293 led_create_state(led_t *func, void *priv, char const *name, int state)
294 {
295 	struct ledsc	*sc;
296 
297 	sc = kmalloc(sizeof *sc, M_LED, M_WAITOK | M_ZERO);
298 
299 	lockmgr(&led_lock2, LK_EXCLUSIVE);
300 	sc->name = kstrdup(name, M_LED);
301 	sc->unit = alloc_unr(led_unit);
302 	sc->private = priv;
303 	sc->func = func;
304 	sc->dev = make_dev(&led_ops, sc->unit,
305 	    UID_ROOT, GID_WHEEL, 0600, "led/%s", name);
306 	lockmgr(&led_lock2, LK_RELEASE);
307 
308 	lockmgr(&led_lock, LK_EXCLUSIVE);
309 	sc->dev->si_drv1 = sc;
310 	LIST_INSERT_HEAD(&led_list, sc, list);
311 	sc->func(sc->private, state != 0);
312 	lockmgr(&led_lock, LK_RELEASE);
313 
314 	return (sc->dev);
315 }
316 
317 void
318 led_destroy(struct cdev *dev)
319 {
320 	struct ledsc *sc;
321 
322 	lockmgr(&led_lock, LK_EXCLUSIVE);
323 	sc = dev->si_drv1;
324 	dev->si_drv1 = NULL;
325 	if (sc->ptr != NULL)
326 		blinkers--;
327 	LIST_REMOVE(sc, list);
328 	if (LIST_EMPTY(&led_list))
329 		callout_stop(&led_ch);
330 	lockmgr(&led_lock, LK_RELEASE);
331 
332 	lockmgr(&led_lock2, LK_EXCLUSIVE);
333 	free_unr(led_unit, sc->unit);
334 	destroy_dev(dev);
335 	if (sc->spec != NULL)
336 		sbuf_delete(sc->spec);
337 	kfree(sc->name, M_LED);
338 	kfree(sc, M_LED);
339 	lockmgr(&led_lock2, LK_RELEASE);
340 }
341 
342 static void
343 led_drvinit(void *unused)
344 {
345 
346 	led_unit = new_unrhdr(0, INT_MAX, NULL);
347 	lockinit(&led_lock, "LED lock", 0, LK_CANRECURSE);
348 	lockinit(&led_lock2, "LED lock2", 0, LK_CANRECURSE);
349 	callout_init_mp(&led_ch);
350 }
351 
352 SYSINIT(leddev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, led_drvinit, NULL);
353