Home | History | Annotate | Line # | Download | only in ebus
gpio_ebus.c revision 1.1
      1 /*	$NetBSD: gpio_ebus.c,v 1.1 2011/01/26 01:18:50 pooka Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2010 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code was written by Alessandro Forin and Neil Pittman
      8  * at Microsoft Research and contributed to The NetBSD Foundation
      9  * by Microsoft Corporation.
     10  *
     11  * Redistribution and use in source and binary forms, with or without
     12  * modification, are permitted provided that the following conditions
     13  * are met:
     14  * 1. Redistributions of source code must retain the above copyright
     15  *    notice, this list of conditions and the following disclaimer.
     16  * 2. Redistributions in binary form must reproduce the above copyright
     17  *    notice, this list of conditions and the following disclaimer in the
     18  *    documentation and/or other materials provided with the distribution.
     19  *
     20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     30  * POSSIBILITY OF SUCH DAMAGE.
     31  */
     32 
     33 #include <sys/cdefs.h>			/* RCS ID & Copyright macro defns */
     34 __KERNEL_RCSID(0, "$NetBSD: gpio_ebus.c,v 1.1 2011/01/26 01:18:50 pooka Exp $");
     35 
     36 #include <sys/param.h>
     37 #include <sys/device.h>
     38 #include <sys/systm.h>
     39 #include <sys/gpio.h>
     40 #include <dev/gpio/gpiovar.h>
     41 
     42 #include <emips/ebus/ebusvar.h>
     43 #include <emips/emips/machdep.h>
     44 #include <machine/emipsreg.h>
     45 
     46 /*
     47  * Device softc
     48  */
     49 #define GPIO_NPINS 32
     50 
     51 struct epio_softc {
     52 	struct device sc_dev;
     53 	struct _Pio *sc_dp;
     54 	struct gpio_chipset_tag	sc_gpio_gc;
     55 	gpio_pin_t		sc_gpio_pins[GPIO_NPINS];
     56 };
     57 
     58 static int	epio_ebus_match (struct device *, struct cfdata *, void *);
     59 static void	epio_ebus_attach (struct device *, struct device *, void *);
     60 
     61 CFATTACH_DECL(epio, sizeof (struct epio_softc),
     62     epio_ebus_match, epio_ebus_attach, NULL, NULL);
     63 
     64 static int	epio_pin_read(void *, int);
     65 static void	epio_pin_write(void *, int, int);
     66 static void	epio_pin_ctl(void *, int, int);
     67 
     68 static int
     69 epio_ebus_match(struct device *parent, struct cfdata *match, void *aux)
     70 {
     71 	struct ebus_attach_args *ia = aux;
     72     struct _Pio *f = (struct _Pio *)ia->ia_vaddr;
     73 
     74 	if (strcmp("gpio", ia->ia_name) != 0)
     75 		return (0);
     76     if ((f == NULL) ||
     77         (f->Tag != PMTTAG_GPIO))
     78 		return (0);
     79 
     80 	return (1);
     81 }
     82 
     83 static void
     84 epio_ebus_attach(struct device *parent, struct device *self, void *aux)
     85 {
     86 	struct ebus_attach_args *ia =aux;
     87 	struct epio_softc *sc = (struct epio_softc *)self;
     88 	struct gpiobus_attach_args gba;
     89     int i;
     90 	uint32_t data;
     91 
     92 	sc->sc_dp = (struct _Pio*)ia->ia_vaddr;
     93 	data = sc->sc_dp->PinData;
     94 
     95 #if DEBUG
     96     printf(" virt=%p data=%zx", (void*)sc->sc_dp, data);
     97 #endif
     98 	printf(": GPIO controller\n");
     99 
    100 	/* BUGBUG Initialize pins properly */
    101 	for (i = 0 ; i < GPIO_NPINS ; i++) {
    102 		sc->sc_gpio_pins[i].pin_num = i;
    103 		sc->sc_gpio_pins[i].pin_caps = GPIO_PIN_INOUT
    104 						| GPIO_PIN_OPENDRAIN
    105 						| GPIO_PIN_TRISTATE;
    106 
    107 		/* current defaults */
    108 		sc->sc_gpio_pins[i].pin_flags = GPIO_PIN_INOUT;
    109 		sc->sc_gpio_pins[i].pin_state = (data & (1 << i)) ? GPIO_PIN_HIGH : GPIO_PIN_LOW;
    110 		sc->sc_gpio_pins[i].pin_mapped = 0;
    111 	}
    112 
    113 	/* Create controller tag */
    114 	sc->sc_gpio_gc.gp_cookie = sc;
    115 	sc->sc_gpio_gc.gp_pin_read = epio_pin_read;
    116 	sc->sc_gpio_gc.gp_pin_write = epio_pin_write;
    117 	sc->sc_gpio_gc.gp_pin_ctl = epio_pin_ctl;
    118 
    119 	gba.gba_gc = &sc->sc_gpio_gc;
    120 	gba.gba_pins = sc->sc_gpio_pins;
    121 	gba.gba_npins = GPIO_NPINS;
    122 
    123 	/* Attach GPIO framework */
    124 	(void) config_found(&sc->sc_dev, &gba, gpiobus_print);
    125 }
    126 
    127 static int
    128 epio_pin_read(void *arg, int pin)
    129 {
    130 	struct epio_softc *sc = arg;
    131 	uint32_t data = sc->sc_dp->PinData;
    132 	int p;
    133 
    134 	p = pin % GPIO_NPINS;
    135 	return (data >> p) & 0x01;
    136 }
    137 
    138 static void
    139 epio_pin_write(void *arg, int pin, int value)
    140 {
    141 	struct epio_softc *sc = arg;
    142 	uint32_t data;
    143 	int p;
    144 
    145 	p = pin % GPIO_NPINS;
    146     data = 1 << p;
    147     if (value)
    148         sc->sc_dp->PinData = data;
    149     else
    150         sc->sc_dp->ClearData = data;
    151 }
    152 
    153 static void
    154 epio_pin_ctl(void *arg, int pin, int flags)
    155 {
    156 	struct epio_softc *sc = arg;
    157 	uint32_t data;
    158 	int p;
    159 
    160 	p = pin % GPIO_NPINS;
    161     data = (1 << p);
    162 
    163 	if (flags & GPIO_PIN_INOUT) {
    164         sc->sc_dp->Direction = data;
    165 	}
    166 
    167 	if (flags & GPIO_PIN_TRISTATE) {
    168         sc->sc_dp->OutDisable = data;
    169 	}
    170 
    171 	if (flags & GPIO_PIN_OPENDRAIN) {
    172         sc->sc_dp->Enable = data;
    173 	}
    174 }
    175