1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 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 __FBSDID("$FreeBSD$"); 31 32 #include <sys/param.h> 33 #include <sys/bus.h> 34 #include <sys/systm.h> 35 #include <sys/module.h> 36 #include <sys/kernel.h> 37 #include <sys/rman.h> 38 #include <sys/sysctl.h> 39 40 #include <machine/bus.h> 41 42 #include <dev/ofw/openfirm.h> 43 #include <dev/pci/pcivar.h> 44 45 #define PCI_VENDOR_ID_NVIDIA 0x10de 46 47 #define NVIDIA_BRIGHT_MIN (0x0ec) 48 #define NVIDIA_BRIGHT_MAX (0x538) 49 #define NVIDIA_BRIGHT_SCALE ((NVIDIA_BRIGHT_MAX - NVIDIA_BRIGHT_MIN)/100) 50 /* nVidia's MMIO registers are at PCI BAR[0] */ 51 #define NVIDIA_MMIO_PMC (0x0) 52 #define NVIDIA_PMC_OFF (NVIDIA_MMIO_PMC + 0x10f0) 53 #define NVIDIA_PMC_BL_SHIFT (16) 54 #define NVIDIA_PMC_BL_EN (1U << 31) 55 56 57 struct nvbl_softc { 58 device_t dev; 59 struct resource *sc_memr; 60 }; 61 62 static void nvbl_identify(driver_t *driver, device_t parent); 63 static int nvbl_probe(device_t dev); 64 static int nvbl_attach(device_t dev); 65 static int nvbl_setlevel(struct nvbl_softc *sc, int newlevel); 66 static int nvbl_getlevel(struct nvbl_softc *sc); 67 static int nvbl_sysctl(SYSCTL_HANDLER_ARGS); 68 69 static device_method_t nvbl_methods[] = { 70 /* Device interface */ 71 DEVMETHOD(device_identify, nvbl_identify), 72 DEVMETHOD(device_probe, nvbl_probe), 73 DEVMETHOD(device_attach, nvbl_attach), 74 {0, 0}, 75 }; 76 77 static driver_t nvbl_driver = { 78 "backlight", 79 nvbl_methods, 80 sizeof(struct nvbl_softc) 81 }; 82 83 static devclass_t nvbl_devclass; 84 85 DRIVER_MODULE(nvbl, vgapci, nvbl_driver, nvbl_devclass, 0, 0); 86 87 static void 88 nvbl_identify(driver_t *driver, device_t parent) 89 { 90 if (OF_finddevice("mac-io/backlight") == -1) 91 return; 92 if (device_find_child(parent, "backlight", -1) == NULL) 93 device_add_child(parent, "backlight", -1); 94 } 95 96 static int 97 nvbl_probe(device_t dev) 98 { 99 char control[8]; 100 phandle_t handle; 101 102 handle = OF_finddevice("mac-io/backlight"); 103 104 if (handle == -1) 105 return (ENXIO); 106 107 if (OF_getprop(handle, "backlight-control", &control, sizeof(control)) < 0) 108 return (ENXIO); 109 110 if ((strcmp(control, "mnca") != 0) || 111 pci_get_vendor(device_get_parent(dev)) != PCI_VENDOR_ID_NVIDIA) 112 return (ENXIO); 113 114 device_set_desc(dev, "PowerBook backlight for nVidia graphics"); 115 116 return (0); 117 } 118 119 static int 120 nvbl_attach(device_t dev) 121 { 122 struct nvbl_softc *sc; 123 struct sysctl_ctx_list *ctx; 124 struct sysctl_oid *tree; 125 int rid; 126 127 sc = device_get_softc(dev); 128 129 rid = 0x10; /* BAR[0], for the MMIO register */ 130 sc->sc_memr = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, 131 RF_ACTIVE | RF_SHAREABLE); 132 if (sc->sc_memr == NULL) { 133 device_printf(dev, "Could not alloc mem resource!\n"); 134 return (ENXIO); 135 } 136 137 /* Turn on big-endian mode */ 138 if (!(bus_read_stream_4(sc->sc_memr, NVIDIA_MMIO_PMC + 4) & 0x01000001)) { 139 bus_write_stream_4(sc->sc_memr, NVIDIA_MMIO_PMC + 4, 0x01000001); 140 mb(); 141 } 142 143 ctx = device_get_sysctl_ctx(dev); 144 tree = device_get_sysctl_tree(dev); 145 146 SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO, 147 "level", CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, sc, 0, 148 nvbl_sysctl, "I", "Backlight level (0-100)"); 149 150 return (0); 151 } 152 153 static int 154 nvbl_setlevel(struct nvbl_softc *sc, int newlevel) 155 { 156 uint32_t pmc_reg; 157 158 if (newlevel > 100) 159 newlevel = 100; 160 161 if (newlevel < 0) 162 newlevel = 0; 163 164 if (newlevel > 0) 165 newlevel = (newlevel * NVIDIA_BRIGHT_SCALE) + NVIDIA_BRIGHT_MIN; 166 167 pmc_reg = bus_read_stream_4(sc->sc_memr, NVIDIA_PMC_OFF) & 0xffff; 168 pmc_reg |= NVIDIA_PMC_BL_EN | (newlevel << NVIDIA_PMC_BL_SHIFT); 169 bus_write_stream_4(sc->sc_memr, NVIDIA_PMC_OFF, pmc_reg); 170 171 return (0); 172 } 173 174 static int 175 nvbl_getlevel(struct nvbl_softc *sc) 176 { 177 uint16_t level; 178 179 level = bus_read_stream_2(sc->sc_memr, NVIDIA_PMC_OFF) & 0x7fff; 180 181 if (level < NVIDIA_BRIGHT_MIN) 182 return 0; 183 184 level = (level - NVIDIA_BRIGHT_MIN) / NVIDIA_BRIGHT_SCALE; 185 186 return (level); 187 } 188 189 static int 190 nvbl_sysctl(SYSCTL_HANDLER_ARGS) 191 { 192 struct nvbl_softc *sc; 193 int newlevel, error; 194 195 sc = arg1; 196 197 newlevel = nvbl_getlevel(sc); 198 199 error = sysctl_handle_int(oidp, &newlevel, 0, req); 200 201 if (error || !req->newptr) 202 return (error); 203 204 return (nvbl_setlevel(sc, newlevel)); 205 } 206