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/cdefs.h> 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 #include <dev/pci/pcivar.h> 42 43 #define PCI_VENDOR_ID_NVIDIA 0x10de 44 45 #define NVIDIA_BRIGHT_MIN (0x0ec) 46 #define NVIDIA_BRIGHT_MAX (0x538) 47 #define NVIDIA_BRIGHT_SCALE ((NVIDIA_BRIGHT_MAX - NVIDIA_BRIGHT_MIN)/100) 48 /* nVidia's MMIO registers are at PCI BAR[0] */ 49 #define NVIDIA_MMIO_PMC (0x0) 50 #define NVIDIA_PMC_OFF (NVIDIA_MMIO_PMC + 0x10f0) 51 #define NVIDIA_PMC_BL_SHIFT (16) 52 #define NVIDIA_PMC_BL_EN (1U << 31) 53 54 struct nvbl_softc { 55 device_t dev; 56 struct resource *sc_memr; 57 }; 58 59 static void nvbl_identify(driver_t *driver, device_t parent); 60 static int nvbl_probe(device_t dev); 61 static int nvbl_attach(device_t dev); 62 static int nvbl_setlevel(struct nvbl_softc *sc, int newlevel); 63 static int nvbl_getlevel(struct nvbl_softc *sc); 64 static int nvbl_sysctl(SYSCTL_HANDLER_ARGS); 65 66 static device_method_t nvbl_methods[] = { 67 /* Device interface */ 68 DEVMETHOD(device_identify, nvbl_identify), 69 DEVMETHOD(device_probe, nvbl_probe), 70 DEVMETHOD(device_attach, nvbl_attach), 71 {0, 0}, 72 }; 73 74 static driver_t nvbl_driver = { 75 "backlight", 76 nvbl_methods, 77 sizeof(struct nvbl_softc) 78 }; 79 80 DRIVER_MODULE(nvbl, vgapci, nvbl_driver, 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 pci_get_vendor(device_get_parent(dev)) != PCI_VENDOR_ID_NVIDIA) 107 return (ENXIO); 108 109 device_set_desc(dev, "PowerBook backlight for nVidia graphics"); 110 111 return (0); 112 } 113 114 static int 115 nvbl_attach(device_t dev) 116 { 117 struct nvbl_softc *sc; 118 struct sysctl_ctx_list *ctx; 119 struct sysctl_oid *tree; 120 int rid; 121 122 sc = device_get_softc(dev); 123 124 rid = 0x10; /* BAR[0], for the MMIO register */ 125 sc->sc_memr = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, 126 RF_ACTIVE | RF_SHAREABLE); 127 if (sc->sc_memr == NULL) { 128 device_printf(dev, "Could not alloc mem resource!\n"); 129 return (ENXIO); 130 } 131 132 /* Turn on big-endian mode */ 133 if (!(bus_read_stream_4(sc->sc_memr, NVIDIA_MMIO_PMC + 4) & 0x01000001)) { 134 bus_write_stream_4(sc->sc_memr, NVIDIA_MMIO_PMC + 4, 0x01000001); 135 mb(); 136 } 137 138 ctx = device_get_sysctl_ctx(dev); 139 tree = device_get_sysctl_tree(dev); 140 141 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 142 "level", CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, sc, 0, 143 nvbl_sysctl, "I", "Backlight level (0-100)"); 144 145 return (0); 146 } 147 148 static int 149 nvbl_setlevel(struct nvbl_softc *sc, int newlevel) 150 { 151 uint32_t pmc_reg; 152 153 if (newlevel > 100) 154 newlevel = 100; 155 156 if (newlevel < 0) 157 newlevel = 0; 158 159 if (newlevel > 0) 160 newlevel = (newlevel * NVIDIA_BRIGHT_SCALE) + NVIDIA_BRIGHT_MIN; 161 162 pmc_reg = bus_read_stream_4(sc->sc_memr, NVIDIA_PMC_OFF) & 0xffff; 163 pmc_reg |= NVIDIA_PMC_BL_EN | (newlevel << NVIDIA_PMC_BL_SHIFT); 164 bus_write_stream_4(sc->sc_memr, NVIDIA_PMC_OFF, pmc_reg); 165 166 return (0); 167 } 168 169 static int 170 nvbl_getlevel(struct nvbl_softc *sc) 171 { 172 uint16_t level; 173 174 level = bus_read_stream_2(sc->sc_memr, NVIDIA_PMC_OFF) & 0x7fff; 175 176 if (level < NVIDIA_BRIGHT_MIN) 177 return 0; 178 179 level = (level - NVIDIA_BRIGHT_MIN) / NVIDIA_BRIGHT_SCALE; 180 181 return (level); 182 } 183 184 static int 185 nvbl_sysctl(SYSCTL_HANDLER_ARGS) 186 { 187 struct nvbl_softc *sc; 188 int newlevel, error; 189 190 sc = arg1; 191 192 newlevel = nvbl_getlevel(sc); 193 194 error = sysctl_handle_int(oidp, &newlevel, 0, req); 195 196 if (error || !req->newptr) 197 return (error); 198 199 return (nvbl_setlevel(sc, newlevel)); 200 } 201