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: stable/12/sys/powerpc/powermac/nvbl.c 326261 2017-11-27 15:09:59Z pfg $");
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
nvbl_identify(driver_t * driver,device_t parent)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
nvbl_probe(device_t dev)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
nvbl_attach(device_t dev)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, sc, 0,
148 nvbl_sysctl, "I", "Backlight level (0-100)");
149
150 return (0);
151 }
152
153 static int
nvbl_setlevel(struct nvbl_softc * sc,int newlevel)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
nvbl_getlevel(struct nvbl_softc * sc)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
nvbl_sysctl(SYSCTL_HANDLER_ARGS)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