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gpioleds.c revision 1.1 
      1 /* $NetBSD: gpioleds.c,v 1.1 2017/07/08 00:55:02 jmcneill Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 2017 Jared McNeill <jmcneill (at) 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 1.1 2017/07/08 00:55:02 jmcneill 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
     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
     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 int
     66 gpioleds_match(device_t parent, cfdata_t cf, void *aux)
     67 {
     68 	const char * const compatible[] = { "gpio-leds", NULL };
     69 	const struct fdt_attach_args *faa = aux;
     70 
     71 	return of_match_compatible(faa->faa_phandle, compatible);
     72 }
     73 
     74 static void
     75 gpioleds_attach(device_t parent, device_t self, void *aux)
     76 {
     77 	const struct fdt_attach_args *faa = aux;
     78 	const int phandle = faa->faa_phandle;
     79 	struct fdtbus_gpio_pin *pin;
     80 	const char *default_state;
     81 	char label[64];
     82 	int child;
     83 
     84 	aprint_naive("\n");
     85 	aprint_normal(":");
     86 
     87 	for (child = OF_child(phandle); child; child = OF_peer(child)) {
     88 		/* Get the label, fallback to node name */
     89 		if (OF_getprop(child, "label", label, sizeof(label)) <= 0 &&
     90 		    OF_getprop(child, "name", label, sizeof(label)) <= 0)
     91 			continue;
     92 
     93 		/* Get the output pin */
     94 		pin = fdtbus_gpio_acquire(child, "gpios", GPIO_PIN_OUTPUT);
     95 		if (pin == NULL)
     96 			continue;
     97 
     98 		/* Attach the LED */
     99 		if (led_attach(label, pin, gpioleds_get, gpioleds_set) == NULL)
    100 			continue;
    101 
    102 		aprint_normal(" %s", label);
    103 
    104 		/* Set default state */
    105 		default_state = fdtbus_get_string(child, "default-state");
    106 		if (default_state && strcmp(default_state, "on") == 0)
    107 			gpioleds_set(pin, LED_STATE_ON);
    108 		else if (default_state && strcmp(default_state, "off") == 0)
    109 			gpioleds_set(pin, LED_STATE_OFF);
    110 	}
    111 
    112 	aprint_normal("\n");
    113 }
    114