freebsd-skq/sys/powerpc/powermac/nvbl.c
Justin Hibbits 1342232fe1 phandle_t is unsigned, and OF_finddevice() returns (phandle_t)(-1) on
failure, so check for that instead of 0.

While here, provide a better description for ATI backlight driver.

Reported by:	jchandra@
MFC after:	3 days
2012-08-21 23:55:29 +00:00

198 lines
5.0 KiB
C

/*-
* Copyright (c) 2012 Justin Hibbits
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/bus.h>
#include <sys/systm.h>
#include <sys/module.h>
#include <sys/kernel.h>
#include <sys/rman.h>
#include <sys/sysctl.h>
#include <machine/bus.h>
#include <dev/ofw/openfirm.h>
#define NVIDIA_BRIGHT_MIN (0x0ec)
#define NVIDIA_BRIGHT_MAX (0x538)
#define NVIDIA_BRIGHT_SCALE ((NVIDIA_BRIGHT_MAX - NVIDIA_BRIGHT_MIN)/100)
/* nVidia's MMIO registers are at PCI BAR[0] */
#define NVIDIA_MMIO_PMC (0x0)
#define NVIDIA_PMC_OFF (NVIDIA_MMIO_PMC + 0x10f0)
#define NVIDIA_PMC_BL_SHIFT (16)
#define NVIDIA_PMC_BL_EN (1 << 31)
struct nvbl_softc {
device_t dev;
struct resource *sc_memr;
};
static void nvbl_identify(driver_t *driver, device_t parent);
static int nvbl_probe(device_t dev);
static int nvbl_attach(device_t dev);
static int nvbl_setlevel(struct nvbl_softc *sc, int newlevel);
static int nvbl_getlevel(struct nvbl_softc *sc);
static int nvbl_sysctl(SYSCTL_HANDLER_ARGS);
static device_method_t nvbl_methods[] = {
/* Device interface */
DEVMETHOD(device_identify, nvbl_identify),
DEVMETHOD(device_probe, nvbl_probe),
DEVMETHOD(device_attach, nvbl_attach),
{0, 0},
};
static driver_t nvbl_driver = {
"backlight",
nvbl_methods,
sizeof(struct nvbl_softc)
};
static devclass_t nvbl_devclass;
DRIVER_MODULE(nvbl, vgapci, nvbl_driver, nvbl_devclass, 0, 0);
static void
nvbl_identify(driver_t *driver, device_t parent)
{
if (device_find_child(parent, "backlight", -1) == NULL)
device_add_child(parent, "backlight", -1);
}
static int
nvbl_probe(device_t dev)
{
char control[8];
phandle_t handle;
handle = OF_finddevice("mac-io/backlight");
if (handle == -1)
return (ENXIO);
if (OF_getprop(handle, "backlight-control", &control, sizeof(control)) < 0)
return (ENXIO);
if (strcmp(control, "mnca") != 0)
return (ENXIO);
device_set_desc(dev, "PowerBook backlight for nVidia graphics");
return (0);
}
static int
nvbl_attach(device_t dev)
{
struct nvbl_softc *sc;
struct sysctl_ctx_list *ctx;
struct sysctl_oid *tree;
int rid;
sc = device_get_softc(dev);
rid = 0x10; /* BAR[0], for the MMIO register */
sc->sc_memr = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
RF_ACTIVE | RF_SHAREABLE);
if (sc->sc_memr == NULL) {
device_printf(dev, "Could not alloc mem resource!\n");
return (ENXIO);
}
/* Turn on big-endian mode */
if (!(bus_read_stream_4(sc->sc_memr, NVIDIA_MMIO_PMC + 4) & 0x01000001)) {
bus_write_stream_4(sc->sc_memr, NVIDIA_MMIO_PMC + 4, 0x01000001);
mb();
}
ctx = device_get_sysctl_ctx(dev);
tree = device_get_sysctl_tree(dev);
SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
"level", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
nvbl_sysctl, "I", "Backlight level (0-100)");
return (0);
}
static int
nvbl_setlevel(struct nvbl_softc *sc, int newlevel)
{
uint32_t pmc_reg;
if (newlevel > 100)
newlevel = 100;
if (newlevel < 0)
newlevel = 0;
if (newlevel > 0)
newlevel = (newlevel * NVIDIA_BRIGHT_SCALE) + NVIDIA_BRIGHT_MIN;
pmc_reg = bus_read_stream_4(sc->sc_memr, NVIDIA_PMC_OFF) & 0xffff;
pmc_reg |= NVIDIA_PMC_BL_EN | (newlevel << NVIDIA_PMC_BL_SHIFT);
bus_write_stream_4(sc->sc_memr, NVIDIA_PMC_OFF, pmc_reg);
return (0);
}
static int
nvbl_getlevel(struct nvbl_softc *sc)
{
uint16_t level;
level = bus_read_stream_2(sc->sc_memr, NVIDIA_PMC_OFF) & 0x7fff;
if (level < NVIDIA_BRIGHT_MIN)
return 0;
level = (level - NVIDIA_BRIGHT_MIN) / NVIDIA_BRIGHT_SCALE;
return (level);
}
static int
nvbl_sysctl(SYSCTL_HANDLER_ARGS)
{
struct nvbl_softc *sc;
int newlevel, error;
sc = arg1;
newlevel = nvbl_getlevel(sc);
error = sysctl_handle_int(oidp, &newlevel, 0, req);
if (error || !req->newptr)
return (error);
return (nvbl_setlevel(sc, newlevel));
}