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/fdt/fdt_common.h> 45 #include <dev/ofw/openfirm.h> 46 #include <dev/ofw/ofw_bus.h> 47 #include <dev/ofw/ofw_bus_subr.h> 48 49 #include "am335x_pwm.h" 50 51 #define ECAP_TSCTR 0x00 52 #define ECAP_CAP1 0x08 53 #define ECAP_CAP2 0x0C 54 #define ECAP_CAP3 0x10 55 #define ECAP_CAP4 0x14 56 #define ECAP_ECCTL2 0x2A 57 #define ECCTL2_MODE_APWM (1 << 9) 58 #define ECCTL2_SYNCO_SEL (3 << 6) 59 #define ECCTL2_TSCTRSTOP_FREERUN (1 << 4) 60 61 #define ECAP_READ2(_sc, reg) bus_read_2((_sc)->sc_mem_res, reg); 62 #define ECAP_WRITE2(_sc, reg, value) \ 63 bus_write_2((_sc)->sc_mem_res, reg, value); 64 #define ECAP_READ4(_sc, reg) bus_read_4((_sc)->sc_mem_res, reg); 65 #define ECAP_WRITE4(_sc, reg, value) \ 66 bus_write_4((_sc)->sc_mem_res, reg, value); 67 68 #define PWM_LOCK(_sc) mtx_lock(&(_sc)->sc_mtx) 69 #define PWM_UNLOCK(_sc) mtx_unlock(&(_sc)->sc_mtx) 70 #define PWM_LOCK_INIT(_sc) mtx_init(&(_sc)->sc_mtx, \ 71 device_get_nameunit(_sc->sc_dev), "am335x_ecap softc", MTX_DEF) 72 #define PWM_LOCK_DESTROY(_sc) mtx_destroy(&(_sc)->sc_mtx) 73 74 static device_probe_t am335x_ecap_probe; 75 static device_attach_t am335x_ecap_attach; 76 static device_detach_t am335x_ecap_detach; 77 78 struct am335x_ecap_softc { 79 device_t sc_dev; 80 struct mtx sc_mtx; 81 struct resource *sc_mem_res; 82 int sc_mem_rid; 83 }; 84 85 static device_method_t am335x_ecap_methods[] = { 86 DEVMETHOD(device_probe, am335x_ecap_probe), 87 DEVMETHOD(device_attach, am335x_ecap_attach), 88 DEVMETHOD(device_detach, am335x_ecap_detach), 89 90 DEVMETHOD_END 91 }; 92 93 static driver_t am335x_ecap_driver = { 94 "am335x_ecap", 95 am335x_ecap_methods, 96 sizeof(struct am335x_ecap_softc), 97 }; 98 99 static devclass_t am335x_ecap_devclass; 100 101 /* 102 * API function to set period/duty cycles for ECAPx 103 */ 104 int 105 am335x_pwm_config_ecap(int unit, int period, int duty) 106 { 107 device_t dev; 108 struct am335x_ecap_softc *sc; 109 uint16_t reg; 110 111 dev = devclass_get_device(am335x_ecap_devclass, unit); 112 if (dev == NULL) 113 return (ENXIO); 114 115 if (duty > period) 116 return (EINVAL); 117 118 if (period == 0) 119 return (EINVAL); 120 121 sc = device_get_softc(dev); 122 PWM_LOCK(sc); 123 124 reg = ECAP_READ2(sc, ECAP_ECCTL2); 125 reg |= ECCTL2_MODE_APWM | ECCTL2_TSCTRSTOP_FREERUN | ECCTL2_SYNCO_SEL; 126 ECAP_WRITE2(sc, ECAP_ECCTL2, reg); 127 128 /* CAP3 in APWM mode is APRD shadow register */ 129 ECAP_WRITE4(sc, ECAP_CAP3, period - 1); 130 131 /* CAP4 in APWM mode is ACMP shadow register */ 132 ECAP_WRITE4(sc, ECAP_CAP4, duty); 133 /* Restart counter */ 134 ECAP_WRITE4(sc, ECAP_TSCTR, 0); 135 136 PWM_UNLOCK(sc); 137 138 return (0); 139 } 140 141 static int 142 am335x_ecap_probe(device_t dev) 143 { 144 145 if (!ofw_bus_status_okay(dev)) 146 return (ENXIO); 147 148 if (!ofw_bus_is_compatible(dev, "ti,am33xx-ecap")) 149 return (ENXIO); 150 151 device_set_desc(dev, "AM335x eCAP"); 152 153 return (BUS_PROBE_DEFAULT); 154 } 155 156 static int 157 am335x_ecap_attach(device_t dev) 158 { 159 struct am335x_ecap_softc *sc; 160 161 sc = device_get_softc(dev); 162 sc->sc_dev = dev; 163 164 PWM_LOCK_INIT(sc); 165 166 sc->sc_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, 167 &sc->sc_mem_rid, RF_ACTIVE); 168 if (sc->sc_mem_res == NULL) { 169 device_printf(dev, "cannot allocate memory resources\n"); 170 goto fail; 171 } 172 173 return (0); 174 175 fail: 176 PWM_LOCK_DESTROY(sc); 177 return (ENXIO); 178 } 179 180 static int 181 am335x_ecap_detach(device_t dev) 182 { 183 struct am335x_ecap_softc *sc; 184 185 sc = device_get_softc(dev); 186 187 PWM_LOCK(sc); 188 if (sc->sc_mem_res) 189 bus_release_resource(dev, SYS_RES_MEMORY, 190 sc->sc_mem_rid, sc->sc_mem_res); 191 PWM_UNLOCK(sc); 192 193 PWM_LOCK_DESTROY(sc); 194 195 196 return (0); 197 } 198 199 DRIVER_MODULE(am335x_ecap, am335x_pwmss, am335x_ecap_driver, am335x_ecap_devclass, 0, 0); 200 MODULE_VERSION(am335x_ecap, 1); 201 MODULE_DEPEND(am335x_ecap, am335x_pwmss, 1, 1, 1); 202