xref: /freebsd/sys/dev/gpio/gpioled.c (revision 46c1105fbb6fbff6d6ccd0a18571342eb992d637)
1 /*-
2  * Copyright (c) 2009 Oleksandr Tymoshenko <gonzo@freebsd.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include "opt_platform.h"
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/bus.h>
35 #include <sys/gpio.h>
36 #include <sys/kernel.h>
37 #include <sys/lock.h>
38 #include <sys/malloc.h>
39 #include <sys/module.h>
40 #include <sys/mutex.h>
41 
42 #ifdef FDT
43 #include <dev/fdt/fdt_common.h>
44 #include <dev/ofw/ofw_bus.h>
45 #endif
46 
47 #include <dev/gpio/gpiobusvar.h>
48 #include <dev/led/led.h>
49 
50 #include "gpiobus_if.h"
51 
52 /*
53  * Only one pin for led
54  */
55 #define	GPIOLED_PIN	0
56 
57 #define	GPIOLED_LOCK(_sc)		mtx_lock(&(_sc)->sc_mtx)
58 #define	GPIOLED_UNLOCK(_sc)		mtx_unlock(&(_sc)->sc_mtx)
59 #define	GPIOLED_LOCK_INIT(_sc)		mtx_init(&(_sc)->sc_mtx,	\
60     device_get_nameunit((_sc)->sc_dev), "gpioled", MTX_DEF)
61 #define	GPIOLED_LOCK_DESTROY(_sc)	mtx_destroy(&(_sc)->sc_mtx)
62 
63 struct gpioled_softc
64 {
65 	device_t	sc_dev;
66 	device_t	sc_busdev;
67 	struct mtx	sc_mtx;
68 	struct cdev	*sc_leddev;
69 };
70 
71 static void gpioled_control(void *, int);
72 static int gpioled_probe(device_t);
73 static int gpioled_attach(device_t);
74 static int gpioled_detach(device_t);
75 
76 static void
77 gpioled_control(void *priv, int onoff)
78 {
79 	struct gpioled_softc *sc;
80 
81 	sc = (struct gpioled_softc *)priv;
82 	GPIOLED_LOCK(sc);
83 	if (GPIOBUS_PIN_SETFLAGS(sc->sc_busdev, sc->sc_dev, GPIOLED_PIN,
84 	    GPIO_PIN_OUTPUT) == 0) {
85 		GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, GPIOLED_PIN,
86 		    onoff ? GPIO_PIN_HIGH : GPIO_PIN_LOW);
87 	}
88 	GPIOLED_UNLOCK(sc);
89 }
90 
91 #ifdef FDT
92 static void
93 gpioled_identify(driver_t *driver, device_t bus)
94 {
95 	phandle_t child, leds, root;
96 
97 	root = OF_finddevice("/");
98 	if (root == 0)
99 		return;
100 	for (leds = OF_child(root); leds != 0; leds = OF_peer(leds)) {
101 		if (!fdt_is_compatible_strict(leds, "gpio-leds"))
102 			continue;
103 		/* Traverse the 'gpio-leds' node and add its children. */
104 		for (child = OF_child(leds); child != 0; child = OF_peer(child)) {
105 			if (!OF_hasprop(child, "gpios"))
106 				continue;
107 			if (ofw_gpiobus_add_fdt_child(bus, driver->name, child) == NULL)
108 				continue;
109 		}
110 	}
111 }
112 #endif
113 
114 static int
115 gpioled_probe(device_t dev)
116 {
117 #ifdef FDT
118 	int match;
119 	phandle_t node;
120 	char *compat;
121 
122 	/*
123 	 * We can match against our own node compatible string and also against
124 	 * our parent node compatible string.  The first is normally used to
125 	 * describe leds on a gpiobus and the later when there is a common node
126 	 * compatible with 'gpio-leds' which is used to concentrate all the
127 	 * leds nodes on the dts.
128 	 */
129 	match = 0;
130 	if (ofw_bus_is_compatible(dev, "gpioled"))
131 		match = 1;
132 
133 	if (match == 0) {
134 		if ((node = ofw_bus_get_node(dev)) == -1)
135 			return (ENXIO);
136 		if ((node = OF_parent(node)) == -1)
137 			return (ENXIO);
138 		if (OF_getprop_alloc(node, "compatible", 1,
139 		    (void **)&compat) == -1)
140 			return (ENXIO);
141 
142 		if (strcasecmp(compat, "gpio-leds") == 0)
143 			match = 1;
144 
145 		OF_prop_free(compat);
146 	}
147 
148 	if (match == 0)
149 		return (ENXIO);
150 #endif
151 	device_set_desc(dev, "GPIO led");
152 
153 	return (BUS_PROBE_DEFAULT);
154 }
155 
156 static int
157 gpioled_attach(device_t dev)
158 {
159 	struct gpioled_softc *sc;
160 	int state;
161 #ifdef FDT
162 	phandle_t node;
163 	char *default_state;
164 	char *name;
165 #else
166 	const char *name;
167 #endif
168 
169 	sc = device_get_softc(dev);
170 	sc->sc_dev = dev;
171 	sc->sc_busdev = device_get_parent(dev);
172 	GPIOLED_LOCK_INIT(sc);
173 
174 	state = 0;
175 
176 #ifdef FDT
177 	if ((node = ofw_bus_get_node(dev)) == -1)
178 		return (ENXIO);
179 
180 	if (OF_getprop_alloc(node, "default-state",
181 	    sizeof(char), (void **)&default_state) != -1) {
182 		if (strcasecmp(default_state, "on") == 0)
183 			state = 1;
184 		else if (strcasecmp(default_state, "off") == 0)
185 			state = 0;
186 		else if (strcasecmp(default_state, "keep") == 0)
187 			state = -1;
188 		else {
189 			device_printf(dev,
190 			    "unknown value for default-state in FDT\n");
191 		}
192 		OF_prop_free(default_state);
193 	}
194 
195 	name = NULL;
196 	if (OF_getprop_alloc(node, "label", 1, (void **)&name) == -1)
197 		OF_getprop_alloc(node, "name", 1, (void **)&name);
198 #else
199 	if (resource_string_value(device_get_name(dev),
200 	    device_get_unit(dev), "name", &name))
201 		name = NULL;
202 #endif
203 
204 	sc->sc_leddev = led_create_state(gpioled_control, sc, name ? name :
205 	    device_get_nameunit(dev), state);
206 #ifdef FDT
207 	if (name != NULL)
208 		OF_prop_free(name);
209 #endif
210 
211 	return (0);
212 }
213 
214 static int
215 gpioled_detach(device_t dev)
216 {
217 	struct gpioled_softc *sc;
218 
219 	sc = device_get_softc(dev);
220 	if (sc->sc_leddev) {
221 		led_destroy(sc->sc_leddev);
222 		sc->sc_leddev = NULL;
223 	}
224 	GPIOLED_LOCK_DESTROY(sc);
225 	return (0);
226 }
227 
228 static devclass_t gpioled_devclass;
229 
230 static device_method_t gpioled_methods[] = {
231 	/* Device interface */
232 #ifdef FDT
233 	DEVMETHOD(device_identify,	gpioled_identify),
234 #endif
235 	DEVMETHOD(device_probe,		gpioled_probe),
236 	DEVMETHOD(device_attach,	gpioled_attach),
237 	DEVMETHOD(device_detach,	gpioled_detach),
238 
239 	DEVMETHOD_END
240 };
241 
242 static driver_t gpioled_driver = {
243 	"gpioled",
244 	gpioled_methods,
245 	sizeof(struct gpioled_softc),
246 };
247 
248 DRIVER_MODULE(gpioled, gpiobus, gpioled_driver, gpioled_devclass, 0, 0);
249 MODULE_DEPEND(gpioled, gpiobus, 1, 1, 1);
250