1 /* $NetBSD: fixedregulator.c,v 1.10 2021/01/27 03:10:21 thorpej 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 1.10 2021/01/27 03:10:21 thorpej 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 const struct device_compatible_entry compat_data[] = { 78 { .compat = "regulator-fixed" }, 79 DEVICE_COMPAT_EOL 80 }; 81 82 static int 83 fixedregulator_match(device_t parent, cfdata_t cf, void *aux) 84 { 85 const struct fdt_attach_args *faa = aux; 86 87 return of_compatible_match(faa->faa_phandle, compat_data); 88 } 89 90 static void 91 fixedregulator_attach(device_t parent, device_t self, void *aux) 92 { 93 struct fixedregulator_softc * const sc = device_private(self); 94 const struct fdt_attach_args *faa = aux; 95 const int phandle = faa->faa_phandle; 96 char *name; 97 int len; 98 99 sc->sc_dev = self; 100 sc->sc_phandle = phandle; 101 102 aprint_naive("\n"); 103 104 len = OF_getproplen(phandle, "regulator-name"); 105 if (len > 0) { 106 name = kmem_zalloc(len, KM_SLEEP); 107 if (OF_getprop(phandle, "regulator-name", name, len) == len) { 108 aprint_normal(": %s\n", name); 109 } else { 110 aprint_normal("\n"); 111 } 112 kmem_free(name, len); 113 } else { 114 aprint_normal("\n"); 115 } 116 117 sc->sc_gpioflags = GPIO_PIN_OUTPUT; 118 if (of_getprop_bool(phandle, "gpio-open-drain")) 119 sc->sc_gpioflags |= GPIO_PIN_OPENDRAIN; 120 121 sc->sc_always_on = of_getprop_bool(phandle, "regulator-always-on"); 122 sc->sc_boot_on = of_getprop_bool(phandle, "regulator-boot-on"); 123 sc->sc_enable_val = of_getprop_bool(phandle, "enable-active-high"); 124 if (of_getprop_uint32(phandle, "startup-delay-us", &sc->sc_delay) != 0) 125 sc->sc_delay = 0; 126 of_getprop_uint32(phandle, "regulator-min-microvolt", &sc->sc_min_uvol); 127 of_getprop_uint32(phandle, "regulator-max-microvolt", &sc->sc_max_uvol); 128 129 sc->sc_pin = fdtbus_gpio_acquire(phandle, "gpio", sc->sc_gpioflags); 130 if (sc->sc_pin == NULL) 131 sc->sc_always_on = OF_getproplen(phandle, "gpio") <= 0; 132 133 fdtbus_register_regulator_controller(self, phandle, 134 &fixedregulator_funcs); 135 136 /* 137 * If the regulator is flagged as always on or enabled at boot, 138 * ensure that it is enabled 139 */ 140 if (sc->sc_always_on || sc->sc_boot_on) 141 fixedregulator_enable(self, true); 142 } 143 144 static int 145 fixedregulator_acquire(device_t dev) 146 { 147 struct fixedregulator_softc * const sc = device_private(dev); 148 149 if (sc->sc_pin == NULL && !sc->sc_always_on) { 150 sc->sc_pin = fdtbus_gpio_acquire(sc->sc_phandle, "gpio", 151 sc->sc_gpioflags); 152 if (sc->sc_pin == NULL) 153 return ENXIO; 154 } 155 156 return 0; 157 } 158 159 static void 160 fixedregulator_release(device_t dev) 161 { 162 } 163 164 static int 165 fixedregulator_enable(device_t dev, bool enable) 166 { 167 struct fixedregulator_softc * const sc = device_private(dev); 168 169 if (enable) { 170 if (sc->sc_pin != NULL) 171 fdtbus_gpio_write_raw(sc->sc_pin, sc->sc_enable_val); 172 if (sc->sc_delay > 0) 173 delay(sc->sc_delay); 174 } else { 175 if (sc->sc_always_on) 176 return EIO; 177 fdtbus_gpio_write_raw(sc->sc_pin, !sc->sc_enable_val); 178 } 179 return 0; 180 } 181 182 static int 183 fixedregulator_set_voltage(device_t dev, u_int min_uvol, u_int max_uvol) 184 { 185 struct fixedregulator_softc * const sc = device_private(dev); 186 187 if (sc->sc_min_uvol > max_uvol || sc->sc_max_uvol < min_uvol) 188 return EINVAL; 189 190 return 0; 191 } 192 193 static int 194 fixedregulator_get_voltage(device_t dev, u_int *uvol) 195 { 196 struct fixedregulator_softc * const sc = device_private(dev); 197 198 *uvol = sc->sc_min_uvol; 199 200 return 0; 201 } 202