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 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 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 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 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 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