1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2012 Justin Hibbits 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/param.h> 30 #include <sys/bus.h> 31 #include <sys/systm.h> 32 #include <sys/module.h> 33 #include <sys/kernel.h> 34 #include <sys/rman.h> 35 #include <sys/sysctl.h> 36 37 #include <machine/bus.h> 38 39 #include <dev/ofw/openfirm.h> 40 #include <dev/pci/pcivar.h> 41 42 #define PCI_VENDOR_ID_NVIDIA 0x10de 43 44 #define NVIDIA_BRIGHT_MIN (0x0ec) 45 #define NVIDIA_BRIGHT_MAX (0x538) 46 #define NVIDIA_BRIGHT_SCALE ((NVIDIA_BRIGHT_MAX - NVIDIA_BRIGHT_MIN)/100) 47 /* nVidia's MMIO registers are at PCI BAR[0] */ 48 #define NVIDIA_MMIO_PMC (0x0) 49 #define NVIDIA_PMC_OFF (NVIDIA_MMIO_PMC + 0x10f0) 50 #define NVIDIA_PMC_BL_SHIFT (16) 51 #define NVIDIA_PMC_BL_EN (1U << 31) 52 53 struct nvbl_softc { 54 device_t dev; 55 struct resource *sc_memr; 56 }; 57 58 static void nvbl_identify(driver_t *driver, device_t parent); 59 static int nvbl_probe(device_t dev); 60 static int nvbl_attach(device_t dev); 61 static int nvbl_setlevel(struct nvbl_softc *sc, int newlevel); 62 static int nvbl_getlevel(struct nvbl_softc *sc); 63 static int nvbl_sysctl(SYSCTL_HANDLER_ARGS); 64 65 static device_method_t nvbl_methods[] = { 66 /* Device interface */ 67 DEVMETHOD(device_identify, nvbl_identify), 68 DEVMETHOD(device_probe, nvbl_probe), 69 DEVMETHOD(device_attach, nvbl_attach), 70 {0, 0}, 71 }; 72 73 static driver_t nvbl_driver = { 74 "backlight", 75 nvbl_methods, 76 sizeof(struct nvbl_softc) 77 }; 78 79 DRIVER_MODULE(nvbl, vgapci, nvbl_driver, 0, 0); 80 81 static void 82 nvbl_identify(driver_t *driver, device_t parent) 83 { 84 if (OF_finddevice("mac-io/backlight") == -1) 85 return; 86 if (device_find_child(parent, "backlight", -1) == NULL) 87 device_add_child(parent, "backlight", DEVICE_UNIT_ANY); 88 } 89 90 static int 91 nvbl_probe(device_t dev) 92 { 93 char control[8]; 94 phandle_t handle; 95 96 handle = OF_finddevice("mac-io/backlight"); 97 98 if (handle == -1) 99 return (ENXIO); 100 101 if (OF_getprop(handle, "backlight-control", &control, sizeof(control)) < 0) 102 return (ENXIO); 103 104 if ((strcmp(control, "mnca") != 0) || 105 pci_get_vendor(device_get_parent(dev)) != PCI_VENDOR_ID_NVIDIA) 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 | CTLFLAG_NEEDGIANT, 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