xref: /freebsd/sys/dev/gpio/gpioled.c (revision e0c83ab3b362c9bd45c5d21683012cecab28d802)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2009 Oleksandr Tymoshenko <gonzo@freebsd.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
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 #include <dev/gpio/gpiobusvar.h>
43 #include <dev/led/led.h>
44 
45 #include "gpiobus_if.h"
46 
47 /*
48  * Only one pin for led
49  */
50 #define	GPIOLED_PIN	0
51 
52 #define	GPIOLED_LOCK(_sc)		mtx_lock(&(_sc)->sc_mtx)
53 #define	GPIOLED_UNLOCK(_sc)		mtx_unlock(&(_sc)->sc_mtx)
54 #define	GPIOLED_LOCK_INIT(_sc)		mtx_init(&(_sc)->sc_mtx,	\
55     device_get_nameunit((_sc)->sc_dev), "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 	int	sc_softinvert;
65 };
66 
67 static void gpioled_control(void *, int);
68 static int gpioled_probe(device_t);
69 static int gpioled_attach(device_t);
70 static int gpioled_detach(device_t);
71 
72 static void
gpioled_control(void * priv,int onoff)73 gpioled_control(void *priv, int onoff)
74 {
75 	struct gpioled_softc *sc;
76 
77 	sc = (struct gpioled_softc *)priv;
78 	if (sc->sc_softinvert)
79 		onoff = !onoff;
80 	GPIOLED_LOCK(sc);
81 	GPIOBUS_PIN_SET(sc->sc_busdev, sc->sc_dev, GPIOLED_PIN,
82 	    onoff ? GPIO_PIN_HIGH : GPIO_PIN_LOW);
83 	GPIOLED_UNLOCK(sc);
84 }
85 
86 static int
gpioled_probe(device_t dev)87 gpioled_probe(device_t dev)
88 {
89 	device_set_desc(dev, "GPIO led");
90 
91 	return (BUS_PROBE_DEFAULT);
92 }
93 
94 static int
gpioled_inv(device_t dev,uint32_t * pin_flags)95 gpioled_inv(device_t dev, uint32_t *pin_flags)
96 {
97 	struct gpioled_softc *sc;
98 	int invert;
99 	uint32_t pin_caps;
100 
101 	sc = device_get_softc(dev);
102 
103 	if (resource_int_value(device_get_name(dev),
104 	    device_get_unit(dev), "invert", &invert))
105 		invert = 0;
106 
107 	if (GPIOBUS_PIN_GETCAPS(sc->sc_busdev, sc->sc_dev, GPIOLED_PIN,
108 	    &pin_caps) != 0) {
109 		if (bootverbose)
110 			device_printf(sc->sc_dev, "unable to get pin caps\n");
111 		return (-1);
112 	}
113 	if (pin_caps & GPIO_PIN_INVOUT)
114 		*pin_flags &= ~GPIO_PIN_INVOUT;
115 	sc->sc_softinvert = 0;
116 	if (invert) {
117 		const char *invmode;
118 
119 		if (resource_string_value(device_get_name(dev),
120 		    device_get_unit(dev), "invmode", &invmode))
121 			invmode = NULL;
122 
123 		if (invmode) {
124 			if (!strcmp(invmode, "sw"))
125 				sc->sc_softinvert = 1;
126 			else if (!strcmp(invmode, "hw")) {
127 				if (pin_caps & GPIO_PIN_INVOUT)
128 					*pin_flags |= GPIO_PIN_INVOUT;
129 				else {
130 					device_printf(sc->sc_dev, "hardware pin inversion not supported\n");
131 					return (-1);
132 				}
133 			} else {
134 				if (strcmp(invmode, "auto") != 0)
135 					device_printf(sc->sc_dev, "invalid pin inversion mode\n");
136 				invmode = NULL;
137 			}
138 		}
139 		/*
140 		 * auto inversion mode: use hardware support if available, else fallback to
141 		 * software emulation.
142 		 */
143 		if (invmode == NULL) {
144 			if (pin_caps & GPIO_PIN_INVOUT)
145 				*pin_flags |= GPIO_PIN_INVOUT;
146 			else
147 				sc->sc_softinvert = 1;
148 		}
149 	}
150 	MPASS(!invert ||
151 	    (((*pin_flags & GPIO_PIN_INVOUT) != 0) && !sc->sc_softinvert) ||
152 	    (((*pin_flags & GPIO_PIN_INVOUT) == 0) && sc->sc_softinvert));
153 	return (invert);
154 }
155 
156 static int
gpioled_attach(device_t dev)157 gpioled_attach(device_t dev)
158 {
159 	struct gpioled_softc *sc;
160 	int state;
161 	const char *name;
162 	uint32_t pin_flags;
163 	int invert;
164 
165 	sc = device_get_softc(dev);
166 	sc->sc_dev = dev;
167 	sc->sc_busdev = device_get_parent(dev);
168 	GPIOLED_LOCK_INIT(sc);
169 
170 	if (resource_string_value(device_get_name(dev),
171 	    device_get_unit(dev), "name", &name))
172 		name = NULL;
173 
174 	if (resource_int_value(device_get_name(dev),
175 	    device_get_unit(dev), "state", &state))
176 		state = 0;
177 
178 	pin_flags = GPIO_PIN_OUTPUT;
179 	invert = gpioled_inv(dev, &pin_flags);
180 	if (invert < 0)
181 		return (ENXIO);
182 	device_printf(sc->sc_dev, "state %d invert %s\n",
183 	    state, (invert ? (sc->sc_softinvert ? "sw" : "hw") : "no"));
184 	if (GPIOBUS_PIN_SETFLAGS(sc->sc_busdev, sc->sc_dev, GPIOLED_PIN,
185 	    pin_flags) != 0) {
186 		if (bootverbose)
187 			device_printf(sc->sc_dev, "unable to set pin flags, %#x\n", pin_flags);
188 		return (ENXIO);
189 	}
190 
191 	sc->sc_leddev = led_create_state(gpioled_control, sc, name ? name :
192 	    device_get_nameunit(dev), state);
193 
194 	return (0);
195 }
196 
197 static int
gpioled_detach(device_t dev)198 gpioled_detach(device_t dev)
199 {
200 	struct gpioled_softc *sc;
201 
202 	sc = device_get_softc(dev);
203 	if (sc->sc_leddev) {
204 		led_destroy(sc->sc_leddev);
205 		sc->sc_leddev = NULL;
206 	}
207 	GPIOLED_LOCK_DESTROY(sc);
208 	return (0);
209 }
210 
211 static device_method_t gpioled_methods[] = {
212 	/* Device interface */
213 	DEVMETHOD(device_probe,		gpioled_probe),
214 	DEVMETHOD(device_attach,	gpioled_attach),
215 	DEVMETHOD(device_detach,	gpioled_detach),
216 
217 	DEVMETHOD_END
218 };
219 
220 static driver_t gpioled_driver = {
221 	"gpioled",
222 	gpioled_methods,
223 	sizeof(struct gpioled_softc),
224 };
225 
226 DRIVER_MODULE(gpioled, gpiobus, gpioled_driver, 0, 0);
227 MODULE_DEPEND(gpioled, gpiobus, 1, 1, 1);
228 MODULE_VERSION(gpioled, 1);
229