xref: /freebsd/sys/dev/gpio/gpioled.c (revision 596596fec79f04e1f413850b44159224ff1fb8dc)
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) \
60 	mtx_init(&_sc->sc_mtx, device_get_nameunit(_sc->sc_dev), \
61 	    "gpioled", MTX_DEF)
62 #define GPIOLED_LOCK_DESTROY(_sc)	mtx_destroy(&_sc->sc_mtx);
63 
64 struct gpioled_softc
65 {
66 	device_t	sc_dev;
67 	device_t	sc_busdev;
68 	struct mtx	sc_mtx;
69 	struct cdev	*sc_leddev;
70 };
71 
72 static void gpioled_control(void *, int);
73 static int gpioled_probe(device_t);
74 static int gpioled_attach(device_t);
75 static int gpioled_detach(device_t);
76 
77 static void
78 gpioled_control(void *priv, int onoff)
79 {
80 	int error;
81 	struct gpioled_softc *sc;
82 
83 	sc = (struct gpioled_softc *)priv;
84 	GPIOLED_LOCK(sc);
85 	error = GPIOBUS_ACQUIRE_BUS(sc->sc_busdev, sc->sc_dev,
86 	    GPIOBUS_DONTWAIT);
87 	if (error != 0) {
88 		GPIOLED_UNLOCK(sc);
89 		return;
90 	}
91 	error = GPIOBUS_PIN_SETFLAGS(sc->sc_busdev, sc->sc_dev,
92 	    GPIOLED_PIN, GPIO_PIN_OUTPUT);
93 	if (error == 0)
94 		GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, GPIOLED_PIN,
95 		    onoff ? GPIO_PIN_HIGH : GPIO_PIN_LOW);
96 	GPIOBUS_RELEASE_BUS(sc->sc_busdev, sc->sc_dev);
97 	GPIOLED_UNLOCK(sc);
98 }
99 
100 #ifdef FDT
101 static void
102 gpioled_identify(driver_t *driver, device_t bus)
103 {
104 	phandle_t child, leds, root;
105 
106 	root = OF_finddevice("/");
107 	if (root == 0)
108 		return;
109 	leds = fdt_find_compatible(root, "gpio-leds", 1);
110 	if (leds == 0)
111 		return;
112 	/* Traverse the 'gpio-leds' node and add its children. */
113 	for (child = OF_child(leds); child != 0; child = OF_peer(child)) {
114 		if (!OF_hasprop(child, "gpios"))
115 			continue;
116 		if (ofw_gpiobus_add_fdt_child(bus, driver->name, child) == NULL)
117 			continue;
118 	}
119 }
120 #endif
121 
122 static int
123 gpioled_probe(device_t dev)
124 {
125 #ifdef FDT
126 	int match;
127 	phandle_t node;
128 	char *compat;
129 
130 	/*
131 	 * We can match against our own node compatible string and also against
132 	 * our parent node compatible string.  The first is normally used to
133 	 * describe leds on a gpiobus and the later when there is a common node
134 	 * compatible with 'gpio-leds' which is used to concentrate all the
135 	 * leds nodes on the dts.
136 	 */
137 	match = 0;
138 	if (ofw_bus_is_compatible(dev, "gpioled"))
139 		match = 1;
140 
141 	if (match == 0) {
142 		if ((node = ofw_bus_get_node(dev)) == -1)
143 			return (ENXIO);
144 		if ((node = OF_parent(node)) == -1)
145 			return (ENXIO);
146 		if (OF_getprop_alloc(node, "compatible", 1,
147 		    (void **)&compat) == -1)
148 			return (ENXIO);
149 
150 		if (strcasecmp(compat, "gpio-leds") == 0)
151 			match = 1;
152 
153 		free(compat, M_OFWPROP);
154 	}
155 
156 	if (match == 0)
157 		return (ENXIO);
158 #endif
159 	device_set_desc(dev, "GPIO led");
160 
161 	return (0);
162 }
163 
164 static int
165 gpioled_attach(device_t dev)
166 {
167 	struct gpioled_softc *sc;
168 #ifdef FDT
169 	phandle_t node;
170 	char *name;
171 #else
172 	const char *name;
173 #endif
174 
175 	sc = device_get_softc(dev);
176 	sc->sc_dev = dev;
177 	sc->sc_busdev = device_get_parent(dev);
178 	GPIOLED_LOCK_INIT(sc);
179 #ifdef FDT
180 	name = NULL;
181 	if ((node = ofw_bus_get_node(dev)) == -1)
182 		return (ENXIO);
183 	if (OF_getprop_alloc(node, "label", 1, (void **)&name) == -1)
184 		OF_getprop_alloc(node, "name", 1, (void **)&name);
185 #else
186 	if (resource_string_value(device_get_name(dev),
187 	    device_get_unit(dev), "name", &name))
188 		name = NULL;
189 #endif
190 
191 	sc->sc_leddev = led_create(gpioled_control, sc, name ? name :
192 	    device_get_nameunit(dev));
193 #ifdef FDT
194 	if (name != NULL)
195 		free(name, M_OFWPROP);
196 #endif
197 
198 	return (0);
199 }
200 
201 static int
202 gpioled_detach(device_t dev)
203 {
204 	struct gpioled_softc *sc;
205 
206 	sc = device_get_softc(dev);
207 	if (sc->sc_leddev) {
208 		led_destroy(sc->sc_leddev);
209 		sc->sc_leddev = NULL;
210 	}
211 	GPIOLED_LOCK_DESTROY(sc);
212 	return (0);
213 }
214 
215 static devclass_t gpioled_devclass;
216 
217 static device_method_t gpioled_methods[] = {
218 	/* Device interface */
219 #ifdef FDT
220 	DEVMETHOD(device_identify,	gpioled_identify),
221 #endif
222 	DEVMETHOD(device_probe,		gpioled_probe),
223 	DEVMETHOD(device_attach,	gpioled_attach),
224 	DEVMETHOD(device_detach,	gpioled_detach),
225 
226 	{ 0, 0 }
227 };
228 
229 static driver_t gpioled_driver = {
230 	"gpioled",
231 	gpioled_methods,
232 	sizeof(struct gpioled_softc),
233 };
234 
235 DRIVER_MODULE(gpioled, gpiobus, gpioled_driver, gpioled_devclass, 0, 0);
236