xref: /freebsd/sys/dev/gpio/gpioled.c (revision cc3f4b99653c34ae64f8a1fddea370abefef680e)
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/bio.h>
35 #include <sys/bus.h>
36 #include <sys/conf.h>
37 #include <sys/kernel.h>
38 #include <sys/kthread.h>
39 #include <sys/lock.h>
40 #include <sys/malloc.h>
41 #include <sys/module.h>
42 #include <sys/mutex.h>
43 
44 #ifdef FDT
45 #include <dev/fdt/fdt_common.h>
46 #include <dev/gpio/gpiobusvar.h>
47 #include <dev/ofw/ofw_bus.h>
48 #endif
49 
50 #include <dev/led/led.h>
51 #include <sys/gpio.h>
52 #include "gpiobus_if.h"
53 
54 /*
55  * Only one pin for led
56  */
57 #define	GPIOLED_PIN	0
58 
59 #define GPIOLED_LOCK(_sc)		mtx_lock(&(_sc)->sc_mtx)
60 #define	GPIOLED_UNLOCK(_sc)		mtx_unlock(&(_sc)->sc_mtx)
61 #define GPIOLED_LOCK_INIT(_sc) \
62 	mtx_init(&_sc->sc_mtx, device_get_nameunit(_sc->sc_dev), \
63 	    "gpioled", MTX_DEF)
64 #define GPIOLED_LOCK_DESTROY(_sc)	mtx_destroy(&_sc->sc_mtx);
65 
66 struct gpioled_softc
67 {
68 	device_t	sc_dev;
69 	device_t	sc_busdev;
70 	struct mtx	sc_mtx;
71 	struct cdev	*sc_leddev;
72 };
73 
74 static void gpioled_control(void *, int);
75 static int gpioled_probe(device_t);
76 static int gpioled_attach(device_t);
77 static int gpioled_detach(device_t);
78 
79 static void
80 gpioled_control(void *priv, int onoff)
81 {
82 	struct gpioled_softc *sc = priv;
83 	GPIOLED_LOCK(sc);
84 	GPIOBUS_LOCK_BUS(sc->sc_busdev);
85 	GPIOBUS_ACQUIRE_BUS(sc->sc_busdev, sc->sc_dev);
86 	GPIOBUS_PIN_SETFLAGS(sc->sc_busdev, sc->sc_dev, GPIOLED_PIN,
87 	    GPIO_PIN_OUTPUT);
88 	GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, GPIOLED_PIN,
89 	    onoff ? GPIO_PIN_HIGH : GPIO_PIN_LOW);
90 	GPIOBUS_RELEASE_BUS(sc->sc_busdev, sc->sc_dev);
91 	GPIOBUS_UNLOCK_BUS(sc->sc_busdev);
92 	GPIOLED_UNLOCK(sc);
93 }
94 
95 #ifdef FDT
96 static void
97 gpioled_identify(driver_t *driver, device_t bus)
98 {
99 	phandle_t child, leds, root;
100 
101 	root = OF_finddevice("/");
102 	if (root == 0)
103 		return;
104 	leds = fdt_find_compatible(root, "gpio-leds", 1);
105 	if (leds == 0)
106 		return;
107 
108 	/* Traverse the 'gpio-leds' node and add its children. */
109 	for (child = OF_child(leds); child != 0; child = OF_peer(child))
110 		if (ofw_gpiobus_add_fdt_child(bus, child) == NULL)
111 			continue;
112 }
113 #endif
114 
115 static int
116 gpioled_probe(device_t dev)
117 {
118 #ifdef FDT
119 	int match;
120 	phandle_t node;
121 	char *compat;
122 
123 	/*
124 	 * We can match against our own node compatible string and also against
125 	 * our parent node compatible string.  The first is normally used to
126 	 * describe leds on a gpiobus and the later when there is a common node
127 	 * compatible with 'gpio-leds' which is used to concentrate all the
128 	 * leds nodes on the dts.
129 	 */
130 	match = 0;
131 	if (ofw_bus_is_compatible(dev, "gpioled"))
132 		match = 1;
133 
134 	if (match == 0) {
135 		if ((node = ofw_bus_get_node(dev)) == -1)
136 			return (ENXIO);
137 		if ((node = OF_parent(node)) == -1)
138 			return (ENXIO);
139 		if (OF_getprop_alloc(node, "compatible", 1,
140 		    (void **)&compat) == -1)
141 			return (ENXIO);
142 
143 		if (strcasecmp(compat, "gpio-leds") == 0)
144 			match = 1;
145 
146 		free(compat, M_OFWPROP);
147 	}
148 
149 	if (match == 0)
150 		return (ENXIO);
151 #endif
152 	device_set_desc(dev, "GPIO led");
153 
154 	return (0);
155 }
156 
157 static int
158 gpioled_attach(device_t dev)
159 {
160 	struct gpioled_softc *sc;
161 #ifdef FDT
162 	phandle_t node;
163 	char *name;
164 #else
165 	const char *name;
166 #endif
167 
168 	sc = device_get_softc(dev);
169 	sc->sc_dev = dev;
170 	sc->sc_busdev = device_get_parent(dev);
171 	GPIOLED_LOCK_INIT(sc);
172 #ifdef FDT
173 	name = NULL;
174 	if ((node = ofw_bus_get_node(dev)) == -1)
175 		return (ENXIO);
176 	if (OF_getprop_alloc(node, "label", 1, (void **)&name) == -1)
177 		OF_getprop_alloc(node, "name", 1, (void **)&name);
178 #else
179 	if (resource_string_value(device_get_name(dev),
180 	    device_get_unit(dev), "name", &name))
181 		name = NULL;
182 #endif
183 
184 	sc->sc_leddev = led_create(gpioled_control, sc, name ? name :
185 	    device_get_nameunit(dev));
186 #ifdef FDT
187 	if (name != NULL)
188 		free(name, M_OFWPROP);
189 #endif
190 
191 	return (0);
192 }
193 
194 static int
195 gpioled_detach(device_t dev)
196 {
197 	struct gpioled_softc *sc;
198 
199 	sc = device_get_softc(dev);
200 	if (sc->sc_leddev) {
201 		led_destroy(sc->sc_leddev);
202 		sc->sc_leddev = NULL;
203 	}
204 	GPIOLED_LOCK_DESTROY(sc);
205 	return (0);
206 }
207 
208 static devclass_t gpioled_devclass;
209 
210 static device_method_t gpioled_methods[] = {
211 	/* Device interface */
212 #ifdef FDT
213 	DEVMETHOD(device_identify,	gpioled_identify),
214 #endif
215 	DEVMETHOD(device_probe,		gpioled_probe),
216 	DEVMETHOD(device_attach,	gpioled_attach),
217 	DEVMETHOD(device_detach,	gpioled_detach),
218 
219 	{ 0, 0 }
220 };
221 
222 static driver_t gpioled_driver = {
223 	"gpioled",
224 	gpioled_methods,
225 	sizeof(struct gpioled_softc),
226 };
227 
228 DRIVER_MODULE(gpioled, gpiobus, gpioled_driver, gpioled_devclass, 0, 0);
229