1 /*- 2 * Copyright (c) 2012 Justin Hibbits 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 ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 19 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 20 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 21 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 22 * 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/bus.h> 32 #include <sys/systm.h> 33 #include <sys/module.h> 34 #include <sys/kernel.h> 35 #include <sys/rman.h> 36 #include <sys/sysctl.h> 37 38 #include <machine/bus.h> 39 40 #include <dev/ofw/openfirm.h> 41 42 #define NVIDIA_BRIGHT_MIN (0x0ec) 43 #define NVIDIA_BRIGHT_MAX (0x538) 44 #define NVIDIA_BRIGHT_SCALE ((NVIDIA_BRIGHT_MAX - NVIDIA_BRIGHT_MIN)/100) 45 /* nVidia's MMIO registers are at PCI BAR[0] */ 46 #define NVIDIA_MMIO_PMC (0x0) 47 #define NVIDIA_PMC_OFF (NVIDIA_MMIO_PMC + 0x10f0) 48 #define NVIDIA_PMC_BL_SHIFT (16) 49 #define NVIDIA_PMC_BL_EN (1U << 31) 50 51 52 struct nvbl_softc { 53 device_t dev; 54 struct resource *sc_memr; 55 }; 56 57 static void nvbl_identify(driver_t *driver, device_t parent); 58 static int nvbl_probe(device_t dev); 59 static int nvbl_attach(device_t dev); 60 static int nvbl_setlevel(struct nvbl_softc *sc, int newlevel); 61 static int nvbl_getlevel(struct nvbl_softc *sc); 62 static int nvbl_sysctl(SYSCTL_HANDLER_ARGS); 63 64 static device_method_t nvbl_methods[] = { 65 /* Device interface */ 66 DEVMETHOD(device_identify, nvbl_identify), 67 DEVMETHOD(device_probe, nvbl_probe), 68 DEVMETHOD(device_attach, nvbl_attach), 69 {0, 0}, 70 }; 71 72 static driver_t nvbl_driver = { 73 "backlight", 74 nvbl_methods, 75 sizeof(struct nvbl_softc) 76 }; 77 78 static devclass_t nvbl_devclass; 79 80 DRIVER_MODULE(nvbl, vgapci, nvbl_driver, nvbl_devclass, 0, 0); 81 82 static void 83 nvbl_identify(driver_t *driver, device_t parent) 84 { 85 if (OF_finddevice("mac-io/backlight") == -1) 86 return; 87 if (device_find_child(parent, "backlight", -1) == NULL) 88 device_add_child(parent, "backlight", -1); 89 } 90 91 static int 92 nvbl_probe(device_t dev) 93 { 94 char control[8]; 95 phandle_t handle; 96 97 handle = OF_finddevice("mac-io/backlight"); 98 99 if (handle == -1) 100 return (ENXIO); 101 102 if (OF_getprop(handle, "backlight-control", &control, sizeof(control)) < 0) 103 return (ENXIO); 104 105 if (strcmp(control, "mnca") != 0) 106 return (ENXIO); 107 108 device_set_desc(dev, "PowerBook backlight for nVidia graphics"); 109 110 return (0); 111 } 112 113 static int 114 nvbl_attach(device_t dev) 115 { 116 struct nvbl_softc *sc; 117 struct sysctl_ctx_list *ctx; 118 struct sysctl_oid *tree; 119 int rid; 120 121 sc = device_get_softc(dev); 122 123 rid = 0x10; /* BAR[0], for the MMIO register */ 124 sc->sc_memr = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, 125 RF_ACTIVE | RF_SHAREABLE); 126 if (sc->sc_memr == NULL) { 127 device_printf(dev, "Could not alloc mem resource!\n"); 128 return (ENXIO); 129 } 130 131 /* Turn on big-endian mode */ 132 if (!(bus_read_stream_4(sc->sc_memr, NVIDIA_MMIO_PMC + 4) & 0x01000001)) { 133 bus_write_stream_4(sc->sc_memr, NVIDIA_MMIO_PMC + 4, 0x01000001); 134 mb(); 135 } 136 137 ctx = device_get_sysctl_ctx(dev); 138 tree = device_get_sysctl_tree(dev); 139 140 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 141 "level", CTLTYPE_INT | CTLFLAG_RW, sc, 0, 142 nvbl_sysctl, "I", "Backlight level (0-100)"); 143 144 return (0); 145 } 146 147 static int 148 nvbl_setlevel(struct nvbl_softc *sc, int newlevel) 149 { 150 uint32_t pmc_reg; 151 152 if (newlevel > 100) 153 newlevel = 100; 154 155 if (newlevel < 0) 156 newlevel = 0; 157 158 if (newlevel > 0) 159 newlevel = (newlevel * NVIDIA_BRIGHT_SCALE) + NVIDIA_BRIGHT_MIN; 160 161 pmc_reg = bus_read_stream_4(sc->sc_memr, NVIDIA_PMC_OFF) & 0xffff; 162 pmc_reg |= NVIDIA_PMC_BL_EN | (newlevel << NVIDIA_PMC_BL_SHIFT); 163 bus_write_stream_4(sc->sc_memr, NVIDIA_PMC_OFF, pmc_reg); 164 165 return (0); 166 } 167 168 static int 169 nvbl_getlevel(struct nvbl_softc *sc) 170 { 171 uint16_t level; 172 173 level = bus_read_stream_2(sc->sc_memr, NVIDIA_PMC_OFF) & 0x7fff; 174 175 if (level < NVIDIA_BRIGHT_MIN) 176 return 0; 177 178 level = (level - NVIDIA_BRIGHT_MIN) / NVIDIA_BRIGHT_SCALE; 179 180 return (level); 181 } 182 183 static int 184 nvbl_sysctl(SYSCTL_HANDLER_ARGS) 185 { 186 struct nvbl_softc *sc; 187 int newlevel, error; 188 189 sc = arg1; 190 191 newlevel = nvbl_getlevel(sc); 192 193 error = sysctl_handle_int(oidp, &newlevel, 0, req); 194 195 if (error || !req->newptr) 196 return (error); 197 198 return (nvbl_setlevel(sc, newlevel)); 199 } 200