1 /*- 2 * Copyright (c) 2013 Oleksandr Tymoshenko <gonzo@freebsd.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include <sys/param.h> 31 #include <sys/systm.h> 32 #include <sys/bus.h> 33 #include <sys/kernel.h> 34 #include <sys/limits.h> 35 #include <sys/lock.h> 36 #include <sys/module.h> 37 #include <sys/mutex.h> 38 #include <sys/resource.h> 39 #include <sys/rman.h> 40 #include <sys/sysctl.h> 41 42 #include <machine/bus.h> 43 44 #include <dev/ofw/openfirm.h> 45 #include <dev/ofw/ofw_bus.h> 46 #include <dev/ofw/ofw_bus_subr.h> 47 48 #include "am335x_pwm.h" 49 50 #define ECAP_TSCTR 0x00 51 #define ECAP_CAP1 0x08 52 #define ECAP_CAP2 0x0C 53 #define ECAP_CAP3 0x10 54 #define ECAP_CAP4 0x14 55 #define ECAP_ECCTL2 0x2A 56 #define ECCTL2_MODE_APWM (1 << 9) 57 #define ECCTL2_SYNCO_SEL (3 << 6) 58 #define ECCTL2_TSCTRSTOP_FREERUN (1 << 4) 59 60 #define ECAP_READ2(_sc, reg) bus_read_2((_sc)->sc_mem_res, reg); 61 #define ECAP_WRITE2(_sc, reg, value) \ 62 bus_write_2((_sc)->sc_mem_res, reg, value); 63 #define ECAP_READ4(_sc, reg) bus_read_4((_sc)->sc_mem_res, reg); 64 #define ECAP_WRITE4(_sc, reg, value) \ 65 bus_write_4((_sc)->sc_mem_res, reg, value); 66 67 #define PWM_LOCK(_sc) mtx_lock(&(_sc)->sc_mtx) 68 #define PWM_UNLOCK(_sc) mtx_unlock(&(_sc)->sc_mtx) 69 #define PWM_LOCK_INIT(_sc) mtx_init(&(_sc)->sc_mtx, \ 70 device_get_nameunit(_sc->sc_dev), "am335x_ecap softc", MTX_DEF) 71 #define PWM_LOCK_DESTROY(_sc) mtx_destroy(&(_sc)->sc_mtx) 72 73 static device_probe_t am335x_ecap_probe; 74 static device_attach_t am335x_ecap_attach; 75 static device_detach_t am335x_ecap_detach; 76 77 struct am335x_ecap_softc { 78 device_t sc_dev; 79 struct mtx sc_mtx; 80 struct resource *sc_mem_res; 81 int sc_mem_rid; 82 }; 83 84 static device_method_t am335x_ecap_methods[] = { 85 DEVMETHOD(device_probe, am335x_ecap_probe), 86 DEVMETHOD(device_attach, am335x_ecap_attach), 87 DEVMETHOD(device_detach, am335x_ecap_detach), 88 89 DEVMETHOD_END 90 }; 91 92 static driver_t am335x_ecap_driver = { 93 "am335x_ecap", 94 am335x_ecap_methods, 95 sizeof(struct am335x_ecap_softc), 96 }; 97 98 /* 99 * API function to set period/duty cycles for ECAPx 100 */ 101 int 102 am335x_pwm_config_ecap(int unit, int period, int duty) 103 { 104 device_t dev; 105 struct am335x_ecap_softc *sc; 106 uint16_t reg; 107 108 dev = devclass_get_device(devclass_find(am335x_ecap_driver.name), unit); 109 if (dev == NULL) 110 return (ENXIO); 111 112 if (duty > period) 113 return (EINVAL); 114 115 if (period == 0) 116 return (EINVAL); 117 118 sc = device_get_softc(dev); 119 PWM_LOCK(sc); 120 121 reg = ECAP_READ2(sc, ECAP_ECCTL2); 122 reg |= ECCTL2_MODE_APWM | ECCTL2_TSCTRSTOP_FREERUN | ECCTL2_SYNCO_SEL; 123 ECAP_WRITE2(sc, ECAP_ECCTL2, reg); 124 125 /* CAP3 in APWM mode is APRD shadow register */ 126 ECAP_WRITE4(sc, ECAP_CAP3, period - 1); 127 128 /* CAP4 in APWM mode is ACMP shadow register */ 129 ECAP_WRITE4(sc, ECAP_CAP4, duty); 130 /* Restart counter */ 131 ECAP_WRITE4(sc, ECAP_TSCTR, 0); 132 133 PWM_UNLOCK(sc); 134 135 return (0); 136 } 137 138 static int 139 am335x_ecap_probe(device_t dev) 140 { 141 142 if (!ofw_bus_status_okay(dev)) 143 return (ENXIO); 144 145 if (!ofw_bus_is_compatible(dev, "ti,am33xx-ecap")) 146 return (ENXIO); 147 148 device_set_desc(dev, "AM335x eCAP"); 149 150 return (BUS_PROBE_DEFAULT); 151 } 152 153 static int 154 am335x_ecap_attach(device_t dev) 155 { 156 struct am335x_ecap_softc *sc; 157 158 sc = device_get_softc(dev); 159 sc->sc_dev = dev; 160 161 PWM_LOCK_INIT(sc); 162 163 sc->sc_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, 164 &sc->sc_mem_rid, RF_ACTIVE); 165 if (sc->sc_mem_res == NULL) { 166 device_printf(dev, "cannot allocate memory resources\n"); 167 goto fail; 168 } 169 170 return (0); 171 172 fail: 173 PWM_LOCK_DESTROY(sc); 174 return (ENXIO); 175 } 176 177 static int 178 am335x_ecap_detach(device_t dev) 179 { 180 struct am335x_ecap_softc *sc; 181 182 sc = device_get_softc(dev); 183 184 PWM_LOCK(sc); 185 if (sc->sc_mem_res) 186 bus_release_resource(dev, SYS_RES_MEMORY, 187 sc->sc_mem_rid, sc->sc_mem_res); 188 PWM_UNLOCK(sc); 189 190 PWM_LOCK_DESTROY(sc); 191 192 return (0); 193 } 194 195 DRIVER_MODULE(am335x_ecap, am335x_pwmss, am335x_ecap_driver, 0, 0); 196 MODULE_VERSION(am335x_ecap, 1); 197 MODULE_DEPEND(am335x_ecap, am335x_pwmss, 1, 1, 1); 198