gpiobutton.c revision 1.2
1 /* $NetBSD: gpiobutton.c,v 1.2 2015/05/30 17:12:16 jmcneill Exp $ */ 2 3 /*- 4 * Copyright (c) 2015 Jared D. 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 "locators.h" 30 31 #include <sys/cdefs.h> 32 __KERNEL_RCSID(0, "$NetBSD: gpiobutton.c,v 1.2 2015/05/30 17:12:16 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/workqueue.h> 41 #include <sys/gpio.h> 42 43 #include <dev/sysmon/sysmonvar.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 struct workqueue *sc_wq; 69 callout_t sc_tick; 70 bool sc_state; 71 struct work sc_work; 72 }; 73 74 static bool gpiobutton_is_pressed(struct gpiobutton_softc *); 75 static void gpiobutton_tick(void *); 76 static void gpiobutton_task(struct work *, void *); 77 78 CFATTACH_DECL_NEW(gpiobutton, sizeof(struct gpiobutton_softc), 79 gpiobutton_match, gpiobutton_attach, NULL, NULL); 80 81 static int 82 gpiobutton_match(device_t parent, cfdata_t cf, void *aux) 83 { 84 struct gpio_attach_args * const ga = aux; 85 86 if (strcmp(ga->ga_dvname, cf->cf_name) != 0) 87 return 0; 88 89 if (ga->ga_offset == -1 || gpio_npins(ga->ga_mask) != 1) 90 return 0; 91 92 const u_int type = __SHIFTOUT(ga->ga_flags, GPIOBUTTON_TYPE_MASK); 93 94 switch (type) { 95 case GPIOBUTTON_TYPE_POWER: 96 case GPIOBUTTON_TYPE_SLEEP: 97 return 1; 98 default: 99 return 0; 100 } 101 } 102 103 static void 104 gpiobutton_attach(device_t parent, device_t self, void *aux) 105 { 106 struct gpiobutton_softc * const sc = device_private(self); 107 struct gpio_attach_args * const ga = aux; 108 const char *desc; 109 int caps, error; 110 111 const u_int type = __SHIFTOUT(ga->ga_flags, GPIOBUTTON_TYPE_MASK); 112 const u_int pol = __SHIFTOUT(ga->ga_flags, GPIOBUTTON_POLARITY_MASK); 113 114 sc->sc_dev = self; 115 sc->sc_gpio = ga->ga_gpio; 116 sc->sc_map.pm_map = sc->sc_pinmap; 117 if (gpio_pin_map(sc->sc_gpio, ga->ga_offset, ga->ga_mask, 118 &sc->sc_map)) { 119 aprint_error(": couldn't map pins\n"); 120 return; 121 } 122 sc->sc_active_high = pol == GPIOBUTTON_POLARITY_ACTIVE_HIGH; 123 124 caps = gpio_pin_caps(sc->sc_gpio, &sc->sc_map, 0); 125 if ((caps & GPIO_PIN_INPUT) == 0) { 126 aprint_error(": pin is not an input pin\n"); 127 return; 128 } 129 130 gpio_pin_ctl(sc->sc_gpio, &sc->sc_map, 0, GPIO_PIN_INPUT); 131 132 sc->sc_smpsw.smpsw_name = device_xname(self); 133 switch (type) { 134 case GPIOBUTTON_TYPE_POWER: 135 sc->sc_smpsw.smpsw_type = PSWITCH_TYPE_POWER; 136 desc = "Power"; 137 break; 138 case GPIOBUTTON_TYPE_SLEEP: 139 sc->sc_smpsw.smpsw_type = PSWITCH_TYPE_SLEEP; 140 desc = "Sleep"; 141 break; 142 default: 143 panic("%s: impossible", __func__); 144 } 145 146 aprint_naive("\n"); 147 aprint_normal(": %s button\n", desc); 148 149 sysmon_pswitch_register(&sc->sc_smpsw); 150 151 callout_init(&sc->sc_tick, CALLOUT_MPSAFE); 152 callout_setfunc(&sc->sc_tick, gpiobutton_tick, sc); 153 154 error = workqueue_create(&sc->sc_wq, device_xname(self), 155 gpiobutton_task, sc, PRI_NONE, IPL_VM, WQ_MPSAFE); 156 if (error) { 157 aprint_error_dev(self, "couldn't create workqueue: %d\n", 158 error); 159 return; 160 } 161 162 gpiobutton_task(&sc->sc_work, sc); 163 } 164 165 static bool 166 gpiobutton_is_pressed(struct gpiobutton_softc *sc) 167 { 168 int val; 169 170 val = gpio_pin_read(sc->sc_gpio, &sc->sc_map, 0); 171 if (!sc->sc_active_high) 172 val = !val; 173 174 return val; 175 } 176 177 static void 178 gpiobutton_tick(void *priv) 179 { 180 struct gpiobutton_softc * const sc = priv; 181 182 workqueue_enqueue(sc->sc_wq, &sc->sc_work, NULL); 183 } 184 185 static void 186 gpiobutton_task(struct work *wk, void *priv) 187 { 188 struct gpiobutton_softc * const sc = priv; 189 190 const bool new_state = gpiobutton_is_pressed(sc); 191 if (new_state != sc->sc_state) { 192 aprint_debug_dev(sc->sc_dev, "button pressed\n"); 193 sysmon_pswitch_event(&sc->sc_smpsw, PSWITCH_EVENT_PRESSED); 194 sc->sc_state = new_state; 195 } 196 197 callout_schedule(&sc->sc_tick, GPIOBUTTON_POLL_INTERVAL); 198 } 199
Indexes created Tue Sep 23 20:09:58 GMT 2025