1 /* $NetBSD: gpiobutton.c,v 1.3 2015/10/04 18:35:44 jmcneill Exp $ */
2
3 /*-
4 * Copyright (c) 2015 Jared D. 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 "locators.h"
30
31 #include <sys/cdefs.h>
32 __KERNEL_RCSID(0, "$NetBSD: gpiobutton.c,v 1.3 2015/10/04 18:35:44 jmcneill Exp $");
33
34 #include <sys/param.h>
35 #include <sys/bus.h>
36 #include <sys/device.h>
37 #include <sys/intr.h>
38 #include <sys/systm.h>
39 #include <sys/kernel.h>
40 #include <sys/gpio.h>
41
42 #include <dev/sysmon/sysmonvar.h>
43 #include <dev/sysmon/sysmon_taskq.h>
44
45 #include <dev/gpio/gpiovar.h>
46
47 #define GPIOBUTTON_POLL_INTERVAL mstohz(200)
48
49 #define GPIOBUTTON_POLARITY_MASK 0x80
50 #define GPIOBUTTON_POLARITY_ACTIVE_LOW 0
51 #define GPIOBUTTON_POLARITY_ACTIVE_HIGH 1
52 #define GPIOBUTTON_TYPE_MASK 0x0f
53 #define GPIOBUTTON_TYPE_POWER 1
54 #define GPIOBUTTON_TYPE_SLEEP 2
55
56 static int gpiobutton_match(device_t, cfdata_t, void *);
57 static void gpiobutton_attach(device_t, device_t, void *);
58
59 struct gpiobutton_softc {
60 device_t sc_dev;
61 void *sc_gpio;
62 struct gpio_pinmap sc_map;
63 int sc_pinmap[1];
64 bool sc_active_high;
65
66 struct sysmon_pswitch sc_smpsw;
67
68 callout_t sc_tick;
69 bool sc_state;
70 };
71
72 static bool gpiobutton_is_pressed(struct gpiobutton_softc *);
73 static void gpiobutton_tick(void *);
74 static void gpiobutton_task(void *);
75
76 CFATTACH_DECL_NEW(gpiobutton, sizeof(struct gpiobutton_softc),
77 gpiobutton_match, gpiobutton_attach, NULL, NULL);
78
79 static int
gpiobutton_match(device_t parent,cfdata_t cf,void * aux)80 gpiobutton_match(device_t parent, cfdata_t cf, void *aux)
81 {
82 struct gpio_attach_args * const ga = aux;
83
84 if (strcmp(ga->ga_dvname, cf->cf_name) != 0)
85 return 0;
86
87 if (ga->ga_offset == -1 || gpio_npins(ga->ga_mask) != 1)
88 return 0;
89
90 const u_int type = __SHIFTOUT(ga->ga_flags, GPIOBUTTON_TYPE_MASK);
91
92 switch (type) {
93 case GPIOBUTTON_TYPE_POWER:
94 case GPIOBUTTON_TYPE_SLEEP:
95 return 1;
96 default:
97 return 0;
98 }
99 }
100
101 static void
gpiobutton_attach(device_t parent,device_t self,void * aux)102 gpiobutton_attach(device_t parent, device_t self, void *aux)
103 {
104 struct gpiobutton_softc * const sc = device_private(self);
105 struct gpio_attach_args * const ga = aux;
106 const char *desc;
107 int caps;
108
109 const u_int type = __SHIFTOUT(ga->ga_flags, GPIOBUTTON_TYPE_MASK);
110 const u_int pol = __SHIFTOUT(ga->ga_flags, GPIOBUTTON_POLARITY_MASK);
111
112 sc->sc_dev = self;
113 sc->sc_gpio = ga->ga_gpio;
114 sc->sc_map.pm_map = sc->sc_pinmap;
115 if (gpio_pin_map(sc->sc_gpio, ga->ga_offset, ga->ga_mask,
116 &sc->sc_map)) {
117 aprint_error(": couldn't map pins\n");
118 return;
119 }
120 sc->sc_active_high = pol == GPIOBUTTON_POLARITY_ACTIVE_HIGH;
121
122 caps = gpio_pin_caps(sc->sc_gpio, &sc->sc_map, 0);
123 if ((caps & GPIO_PIN_INPUT) == 0) {
124 aprint_error(": pin is not an input pin\n");
125 return;
126 }
127
128 gpio_pin_ctl(sc->sc_gpio, &sc->sc_map, 0, GPIO_PIN_INPUT);
129
130 sc->sc_smpsw.smpsw_name = device_xname(self);
131 switch (type) {
132 case GPIOBUTTON_TYPE_POWER:
133 sc->sc_smpsw.smpsw_type = PSWITCH_TYPE_POWER;
134 desc = "Power";
135 break;
136 case GPIOBUTTON_TYPE_SLEEP:
137 sc->sc_smpsw.smpsw_type = PSWITCH_TYPE_SLEEP;
138 desc = "Sleep";
139 break;
140 default:
141 panic("%s: impossible", __func__);
142 }
143
144 aprint_naive("\n");
145 aprint_normal(": %s button\n", desc);
146
147 sysmon_pswitch_register(&sc->sc_smpsw);
148
149 callout_init(&sc->sc_tick, CALLOUT_MPSAFE);
150 callout_setfunc(&sc->sc_tick, gpiobutton_tick, sc);
151
152 gpiobutton_tick(sc);
153 }
154
155 static bool
gpiobutton_is_pressed(struct gpiobutton_softc * sc)156 gpiobutton_is_pressed(struct gpiobutton_softc *sc)
157 {
158 int val;
159
160 val = gpio_pin_read(sc->sc_gpio, &sc->sc_map, 0);
161 if (!sc->sc_active_high)
162 val = !val;
163
164 return val;
165 }
166
167 static void
gpiobutton_tick(void * priv)168 gpiobutton_tick(void *priv)
169 {
170 struct gpiobutton_softc * const sc = priv;
171
172 const bool new_state = gpiobutton_is_pressed(sc);
173 if (new_state != sc->sc_state) {
174 sc->sc_state = new_state;
175 sysmon_task_queue_sched(0, gpiobutton_task, sc);
176 }
177 callout_schedule(&sc->sc_tick, GPIOBUTTON_POLL_INTERVAL);
178 }
179
180 static void
gpiobutton_task(void * priv)181 gpiobutton_task(void *priv)
182 {
183 struct gpiobutton_softc * const sc = priv;
184
185 sysmon_pswitch_event(&sc->sc_smpsw,
186 sc->sc_state ? PSWITCH_EVENT_PRESSED : PSWITCH_EVENT_RELEASED);
187 }
188