1 /* $NetBSD: fixedregulator.c,v 1.8 2019/05/23 21:36:26 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 <sys/cdefs.h> 30 __KERNEL_RCSID(0, "$NetBSD: fixedregulator.c,v 1.8 2019/05/23 21:36:26 jmcneill Exp $"); 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/device.h> 35 #include <sys/kmem.h> 36 #include <sys/bus.h> 37 #include <sys/gpio.h> 38 39 #include <dev/fdt/fdtvar.h> 40 41 static int fixedregulator_match(device_t, cfdata_t, void *); 42 static void fixedregulator_attach(device_t, device_t, void *); 43 44 static int fixedregulator_acquire(device_t); 45 static void fixedregulator_release(device_t); 46 static int fixedregulator_enable(device_t, bool); 47 static int fixedregulator_set_voltage(device_t, u_int, u_int); 48 static int fixedregulator_get_voltage(device_t, u_int *); 49 50 struct fdtbus_regulator_controller_func fixedregulator_funcs = { 51 .acquire = fixedregulator_acquire, 52 .release = fixedregulator_release, 53 .enable = fixedregulator_enable, 54 .set_voltage = fixedregulator_set_voltage, 55 .get_voltage = fixedregulator_get_voltage, 56 }; 57 58 struct fixedregulator_softc { 59 device_t sc_dev; 60 int sc_phandle; 61 62 struct fdtbus_gpio_pin *sc_pin; 63 bool sc_always_on; 64 bool sc_boot_on; 65 bool sc_enable_val; 66 uint32_t sc_delay; 67 uint32_t sc_min_uvol; 68 uint32_t sc_max_uvol; 69 70 int sc_gpioflags; 71 bool sc_deferred; 72 }; 73 74 CFATTACH_DECL_NEW(fregulator, sizeof(struct fixedregulator_softc), 75 fixedregulator_match, fixedregulator_attach, NULL, NULL); 76 77 static int 78 fixedregulator_match(device_t parent, cfdata_t cf, void *aux) 79 { 80 const char * const compatible[] = { "regulator-fixed", NULL }; 81 const struct fdt_attach_args *faa = aux; 82 83 return of_match_compatible(faa->faa_phandle, compatible); 84 } 85 86 static void 87 fixedregulator_attach(device_t parent, device_t self, void *aux) 88 { 89 struct fixedregulator_softc * const sc = device_private(self); 90 const struct fdt_attach_args *faa = aux; 91 const int phandle = faa->faa_phandle; 92 char *name; 93 int len; 94 95 sc->sc_dev = self; 96 sc->sc_phandle = phandle; 97 98 aprint_naive("\n"); 99 100 len = OF_getproplen(phandle, "regulator-name"); 101 if (len > 0) { 102 name = kmem_zalloc(len, KM_SLEEP); 103 if (OF_getprop(phandle, "regulator-name", name, len) == len) { 104 aprint_normal(": %s\n", name); 105 } else { 106 aprint_normal("\n"); 107 } 108 kmem_free(name, len); 109 } else { 110 aprint_normal("\n"); 111 } 112 113 sc->sc_gpioflags = GPIO_PIN_OUTPUT; 114 if (of_getprop_bool(phandle, "gpio-open-drain")) 115 sc->sc_gpioflags |= GPIO_PIN_OPENDRAIN; 116 117 sc->sc_always_on = of_getprop_bool(phandle, "regulator-always-on"); 118 sc->sc_boot_on = of_getprop_bool(phandle, "regulator-boot-on"); 119 sc->sc_enable_val = of_getprop_bool(phandle, "enable-active-high"); 120 if (of_getprop_uint32(phandle, "startup-delay-us", &sc->sc_delay) != 0) 121 sc->sc_delay = 0; 122 of_getprop_uint32(phandle, "regulator-min-microvolt", &sc->sc_min_uvol); 123 of_getprop_uint32(phandle, "regulator-max-microvolt", &sc->sc_max_uvol); 124 125 sc->sc_pin = fdtbus_gpio_acquire(phandle, "gpio", sc->sc_gpioflags); 126 if (sc->sc_pin == NULL) 127 sc->sc_always_on = OF_getproplen(phandle, "gpio") <= 0; 128 129 fdtbus_register_regulator_controller(self, phandle, 130 &fixedregulator_funcs); 131 132 /* 133 * If the regulator is flagged as always on or enabled at boot, 134 * ensure that it is enabled 135 */ 136 if (sc->sc_always_on || sc->sc_boot_on) 137 fixedregulator_enable(self, true); 138 } 139 140 static int 141 fixedregulator_acquire(device_t dev) 142 { 143 struct fixedregulator_softc * const sc = device_private(dev); 144 145 if (sc->sc_pin == NULL && !sc->sc_always_on) { 146 sc->sc_pin = fdtbus_gpio_acquire(sc->sc_phandle, "gpio", 147 sc->sc_gpioflags); 148 if (sc->sc_pin == NULL) 149 return ENXIO; 150 } 151 152 return 0; 153 } 154 155 static void 156 fixedregulator_release(device_t dev) 157 { 158 } 159 160 static int 161 fixedregulator_enable(device_t dev, bool enable) 162 { 163 struct fixedregulator_softc * const sc = device_private(dev); 164 165 if (enable) { 166 if (sc->sc_pin != NULL) 167 fdtbus_gpio_write_raw(sc->sc_pin, sc->sc_enable_val); 168 if (sc->sc_delay > 0) 169 delay(sc->sc_delay); 170 } else { 171 if (sc->sc_always_on) 172 return EIO; 173 fdtbus_gpio_write_raw(sc->sc_pin, !sc->sc_enable_val); 174 } 175 return 0; 176 } 177 178 static int 179 fixedregulator_set_voltage(device_t dev, u_int min_uvol, u_int max_uvol) 180 { 181 struct fixedregulator_softc * const sc = device_private(dev); 182 183 if (sc->sc_min_uvol > max_uvol || sc->sc_max_uvol < min_uvol) 184 return EINVAL; 185 186 return 0; 187 } 188 189 static int 190 fixedregulator_get_voltage(device_t dev, u_int *uvol) 191 { 192 struct fixedregulator_softc * const sc = device_private(dev); 193 194 *uvol = sc->sc_min_uvol; 195 196 return 0; 197 } 198