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 static devclass_t am335x_ecap_devclass; 99 100 /* 101 * API function to set period/duty cycles for ECAPx 102 */ 103 int 104 am335x_pwm_config_ecap(int unit, int period, int duty) 105 { 106 device_t dev; 107 struct am335x_ecap_softc *sc; 108 uint16_t reg; 109 110 dev = devclass_get_device(am335x_ecap_devclass, unit); 111 if (dev == NULL) 112 return (ENXIO); 113 114 if (duty > period) 115 return (EINVAL); 116 117 if (period == 0) 118 return (EINVAL); 119 120 sc = device_get_softc(dev); 121 PWM_LOCK(sc); 122 123 reg = ECAP_READ2(sc, ECAP_ECCTL2); 124 reg |= ECCTL2_MODE_APWM | ECCTL2_TSCTRSTOP_FREERUN | ECCTL2_SYNCO_SEL; 125 ECAP_WRITE2(sc, ECAP_ECCTL2, reg); 126 127 /* CAP3 in APWM mode is APRD shadow register */ 128 ECAP_WRITE4(sc, ECAP_CAP3, period - 1); 129 130 /* CAP4 in APWM mode is ACMP shadow register */ 131 ECAP_WRITE4(sc, ECAP_CAP4, duty); 132 /* Restart counter */ 133 ECAP_WRITE4(sc, ECAP_TSCTR, 0); 134 135 PWM_UNLOCK(sc); 136 137 return (0); 138 } 139 140 static int 141 am335x_ecap_probe(device_t dev) 142 { 143 144 if (!ofw_bus_status_okay(dev)) 145 return (ENXIO); 146 147 if (!ofw_bus_is_compatible(dev, "ti,am33xx-ecap")) 148 return (ENXIO); 149 150 device_set_desc(dev, "AM335x eCAP"); 151 152 return (BUS_PROBE_DEFAULT); 153 } 154 155 static int 156 am335x_ecap_attach(device_t dev) 157 { 158 struct am335x_ecap_softc *sc; 159 160 sc = device_get_softc(dev); 161 sc->sc_dev = dev; 162 163 PWM_LOCK_INIT(sc); 164 165 sc->sc_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, 166 &sc->sc_mem_rid, RF_ACTIVE); 167 if (sc->sc_mem_res == NULL) { 168 device_printf(dev, "cannot allocate memory resources\n"); 169 goto fail; 170 } 171 172 return (0); 173 174 fail: 175 PWM_LOCK_DESTROY(sc); 176 return (ENXIO); 177 } 178 179 static int 180 am335x_ecap_detach(device_t dev) 181 { 182 struct am335x_ecap_softc *sc; 183 184 sc = device_get_softc(dev); 185 186 PWM_LOCK(sc); 187 if (sc->sc_mem_res) 188 bus_release_resource(dev, SYS_RES_MEMORY, 189 sc->sc_mem_rid, sc->sc_mem_res); 190 PWM_UNLOCK(sc); 191 192 PWM_LOCK_DESTROY(sc); 193 194 195 return (0); 196 } 197 198 DRIVER_MODULE(am335x_ecap, am335x_pwmss, am335x_ecap_driver, am335x_ecap_devclass, 0, 0); 199 MODULE_VERSION(am335x_ecap, 1); 200 MODULE_DEPEND(am335x_ecap, am335x_pwmss, 1, 1, 1); 201