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