xref: /netbsd-src/sys/dev/fdt/gpioleds.c (revision 6e54367a22fbc89a1139d033e95bec0c0cf0975b)
1 /* $NetBSD: gpioleds.c,v 1.2 2021/01/27 03:10:21 thorpej Exp $ */
2 
3 /*-
4  * Copyright (c) 2017 Jared McNeill <jmcneill@invisible.ca>
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 ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * 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 __KERNEL_RCSID(0, "$NetBSD: gpioleds.c,v 1.2 2021/01/27 03:10:21 thorpej Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/kernel.h>
34 #include <sys/systm.h>
35 #include <sys/device.h>
36 #include <sys/kmem.h>
37 #include <sys/bus.h>
38 #include <sys/gpio.h>
39 
40 #include <dev/led.h>
41 
42 #include <dev/fdt/fdtvar.h>
43 
44 static int	gpioleds_match(device_t, cfdata_t, void *);
45 static void	gpioleds_attach(device_t, device_t, void *);
46 
47 CFATTACH_DECL_NEW(gpioleds, 0, gpioleds_match, gpioleds_attach, NULL, NULL);
48 
49 static int
gpioleds_get(void * priv)50 gpioleds_get(void *priv)
51 {
52 	struct fdtbus_gpio_pin *pin = priv;
53 
54 	return fdtbus_gpio_read(pin);
55 }
56 
57 static void
gpioleds_set(void * priv,int state)58 gpioleds_set(void *priv, int state)
59 {
60 	struct fdtbus_gpio_pin *pin = priv;
61 
62 	fdtbus_gpio_write(pin, state);
63 }
64 
65 static const struct device_compatible_entry compat_data[] = {
66 	{ .compat = "gpio-leds" },
67 	DEVICE_COMPAT_EOL
68 };
69 
70 static int
gpioleds_match(device_t parent,cfdata_t cf,void * aux)71 gpioleds_match(device_t parent, cfdata_t cf, void *aux)
72 {
73 	const struct fdt_attach_args *faa = aux;
74 
75 	return of_compatible_match(faa->faa_phandle, compat_data);
76 }
77 
78 static void
gpioleds_attach(device_t parent,device_t self,void * aux)79 gpioleds_attach(device_t parent, device_t self, void *aux)
80 {
81 	const struct fdt_attach_args *faa = aux;
82 	const int phandle = faa->faa_phandle;
83 	struct fdtbus_gpio_pin *pin;
84 	const char *default_state;
85 	char label[64];
86 	int child;
87 
88 	aprint_naive("\n");
89 	aprint_normal(":");
90 
91 	for (child = OF_child(phandle); child; child = OF_peer(child)) {
92 		/* Get the label, fallback to node name */
93 		if (OF_getprop(child, "label", label, sizeof(label)) <= 0 &&
94 		    OF_getprop(child, "name", label, sizeof(label)) <= 0)
95 			continue;
96 
97 		/* Get the output pin */
98 		pin = fdtbus_gpio_acquire(child, "gpios", GPIO_PIN_OUTPUT);
99 		if (pin == NULL)
100 			continue;
101 
102 		/* Attach the LED */
103 		if (led_attach(label, pin, gpioleds_get, gpioleds_set) == NULL)
104 			continue;
105 
106 		aprint_normal(" %s", label);
107 
108 		/* Set default state */
109 		default_state = fdtbus_get_string(child, "default-state");
110 		if (default_state && strcmp(default_state, "on") == 0)
111 			gpioleds_set(pin, LED_STATE_ON);
112 		else if (default_state && strcmp(default_state, "off") == 0)
113 			gpioleds_set(pin, LED_STATE_OFF);
114 	}
115 
116 	aprint_normal("\n");
117 }
118