1 /* $NetBSD: gpio_ebus.c,v 1.5 2021/08/07 16:18:48 thorpej 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 1.5 2021/08/07 16:18:48 thorpej 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 device_t 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(device_t, cfdata_t, void *);
59 static void epio_ebus_attach(device_t, device_t, void *);
60
61 CFATTACH_DECL_NEW(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
epio_ebus_match(device_t parent,cfdata_t cf,void * aux)69 epio_ebus_match(device_t parent, cfdata_t cf, 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
epio_ebus_attach(device_t parent,device_t self,void * aux)84 epio_ebus_attach(device_t parent, device_t self, void *aux)
85 {
86 struct epio_softc *sc = device_private(self);
87 struct ebus_attach_args *ia =aux;
88 struct gpiobus_attach_args gba;
89 int i;
90 uint32_t data;
91
92 sc->sc_dev = self;
93 sc->sc_dp = (struct _Pio *)ia->ia_vaddr;
94 data = sc->sc_dp->PinData;
95
96 #if DEBUG
97 printf(" virt=%p data=%zx", (void*)sc->sc_dp, data);
98 #endif
99 printf(": GPIO controller\n");
100
101 /* BUGBUG Initialize pins properly */
102 for (i = 0 ; i < GPIO_NPINS ; i++) {
103 sc->sc_gpio_pins[i].pin_num = i;
104 sc->sc_gpio_pins[i].pin_caps =
105 GPIO_PIN_INOUT |
106 GPIO_PIN_OPENDRAIN |
107 GPIO_PIN_TRISTATE;
108
109 /* current defaults */
110 sc->sc_gpio_pins[i].pin_flags = GPIO_PIN_INOUT;
111 sc->sc_gpio_pins[i].pin_state =
112 (data & (1 << i)) ? GPIO_PIN_HIGH : GPIO_PIN_LOW;
113 sc->sc_gpio_pins[i].pin_mapped = 0;
114 }
115
116 /* Create controller tag */
117 sc->sc_gpio_gc.gp_cookie = sc;
118 sc->sc_gpio_gc.gp_pin_read = epio_pin_read;
119 sc->sc_gpio_gc.gp_pin_write = epio_pin_write;
120 sc->sc_gpio_gc.gp_pin_ctl = epio_pin_ctl;
121
122 gba.gba_gc = &sc->sc_gpio_gc;
123 gba.gba_pins = sc->sc_gpio_pins;
124 gba.gba_npins = GPIO_NPINS;
125
126 /* Attach GPIO framework */
127 (void)config_found(self, &gba, gpiobus_print, CFARGS_NONE);
128 }
129
130 static int
epio_pin_read(void * arg,int pin)131 epio_pin_read(void *arg, int pin)
132 {
133 struct epio_softc *sc = arg;
134 uint32_t data = sc->sc_dp->PinData;
135 int p;
136
137 p = pin % GPIO_NPINS;
138 return (data >> p) & 0x01;
139 }
140
141 static void
epio_pin_write(void * arg,int pin,int value)142 epio_pin_write(void *arg, int pin, int value)
143 {
144 struct epio_softc *sc = arg;
145 uint32_t data;
146 int p;
147
148 p = pin % GPIO_NPINS;
149 data = 1 << p;
150 if (value)
151 sc->sc_dp->PinData = data;
152 else
153 sc->sc_dp->ClearData = data;
154 }
155
156 static void
epio_pin_ctl(void * arg,int pin,int flags)157 epio_pin_ctl(void *arg, int pin, int flags)
158 {
159 struct epio_softc *sc = arg;
160 uint32_t data;
161 int p;
162
163 p = pin % GPIO_NPINS;
164 data = (1 << p);
165
166 if (flags & GPIO_PIN_INOUT) {
167 sc->sc_dp->Direction = data;
168 }
169
170 if (flags & GPIO_PIN_TRISTATE) {
171 sc->sc_dp->OutDisable = data;
172 }
173
174 if (flags & GPIO_PIN_OPENDRAIN) {
175 sc->sc_dp->Enable = data;
176 }
177 }
178