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