xref: /freebsd/sys/dev/gpio/gpioled.c (revision 2f02600abfddfc4e9f20dd384a2e729b451e16bd)
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 <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bio.h>
33 #include <sys/bus.h>
34 #include <sys/conf.h>
35 #include <sys/kernel.h>
36 #include <sys/kthread.h>
37 #include <sys/lock.h>
38 #include <sys/malloc.h>
39 #include <sys/module.h>
40 #include <sys/mutex.h>
41 
42 #include <dev/led/led.h>
43 #include <sys/gpio.h>
44 #include "gpiobus_if.h"
45 
46 /*
47  * Only one pin for led
48  */
49 #define	GPIOLED_PIN	0
50 
51 #define GPIOLED_LOCK(_sc)		mtx_lock(&(_sc)->sc_mtx)
52 #define	GPIOLED_UNLOCK(_sc)		mtx_unlock(&(_sc)->sc_mtx)
53 #define GPIOLED_LOCK_INIT(_sc) \
54 	mtx_init(&_sc->sc_mtx, device_get_nameunit(_sc->sc_dev), \
55 	    "gpioled", MTX_DEF)
56 #define GPIOLED_LOCK_DESTROY(_sc)	mtx_destroy(&_sc->sc_mtx);
57 
58 struct gpioled_softc
59 {
60 	device_t	sc_dev;
61 	device_t	sc_busdev;
62 	struct mtx	sc_mtx;
63 	struct cdev	*sc_leddev;
64 };
65 
66 static void gpioled_control(void *, int);
67 static int gpioled_probe(device_t);
68 static int gpioled_attach(device_t);
69 static int gpioled_detach(device_t);
70 
71 static void
72 gpioled_control(void *priv, int onoff)
73 {
74 	struct gpioled_softc *sc = priv;
75 	GPIOLED_LOCK(sc);
76 	GPIOBUS_LOCK_BUS(sc->sc_busdev);
77 	GPIOBUS_ACQUIRE_BUS(sc->sc_busdev, sc->sc_dev);
78 	GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, GPIOLED_PIN,
79 	    onoff ? GPIO_PIN_HIGH : GPIO_PIN_LOW);
80 	GPIOBUS_RELEASE_BUS(sc->sc_busdev, sc->sc_dev);
81 	GPIOBUS_UNLOCK_BUS(sc->sc_busdev);
82 	GPIOLED_UNLOCK(sc);
83 }
84 
85 static int
86 gpioled_probe(device_t dev)
87 {
88 	device_set_desc(dev, "GPIO led");
89 	return (0);
90 }
91 
92 static int
93 gpioled_attach(device_t dev)
94 {
95 	struct gpioled_softc *sc;
96 	const char *name;
97 
98 	sc = device_get_softc(dev);
99 	sc->sc_dev = dev;
100 	sc->sc_busdev = device_get_parent(dev);
101 	GPIOLED_LOCK_INIT(sc);
102 	if (resource_string_value(device_get_name(dev),
103 	    device_get_unit(dev), "name", &name))
104 		name = NULL;
105 
106 	GPIOBUS_PIN_SETFLAGS(sc->sc_busdev, sc->sc_dev, GPIOLED_PIN,
107 	    GPIO_PIN_OUTPUT);
108 
109 	sc->sc_leddev = led_create(gpioled_control, sc, name ? name :
110 	    device_get_nameunit(dev));
111 
112 	return (0);
113 }
114 
115 static int
116 gpioled_detach(device_t dev)
117 {
118 	struct gpioled_softc *sc;
119 
120 	sc = device_get_softc(dev);
121 	if (sc->sc_leddev) {
122 		led_destroy(sc->sc_leddev);
123 		sc->sc_leddev = NULL;
124 	}
125 	GPIOLED_LOCK_DESTROY(sc);
126 	return (0);
127 }
128 
129 static devclass_t gpioled_devclass;
130 
131 static device_method_t gpioled_methods[] = {
132 	/* Device interface */
133 	DEVMETHOD(device_probe,		gpioled_probe),
134 	DEVMETHOD(device_attach,	gpioled_attach),
135 	DEVMETHOD(device_detach,	gpioled_detach),
136 
137 	{ 0, 0 }
138 };
139 
140 static driver_t gpioled_driver = {
141 	"gpioled",
142 	gpioled_methods,
143 	sizeof(struct gpioled_softc),
144 };
145 
146 DRIVER_MODULE(gpioled, gpiobus, gpioled_driver, gpioled_devclass, 0, 0);
147