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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Backlight code for nVidia based graphic cards4 *5 * Copyright 2004 Antonino Daplas <adaplas@pol.net>6 * Copyright (c) 2006 Michael Hanselmann <linux-kernel@hansmi.ch>7 */8 9#include <linux/backlight.h>10#include <linux/fb.h>11#include <linux/pci.h>12 13#ifdef CONFIG_PMAC_BACKLIGHT14#include <asm/backlight.h>15#endif16 17#include "nv_local.h"18#include "nv_type.h"19#include "nv_proto.h"20 21/* We do not have any information about which values are allowed, thus22 * we used safe values.23 */24#define MIN_LEVEL 0x15825#define MAX_LEVEL 0x53426#define LEVEL_STEP ((MAX_LEVEL - MIN_LEVEL) / FB_BACKLIGHT_MAX)27 28static int nvidia_bl_get_level_brightness(struct nvidia_par *par,29 int level)30{31 struct fb_info *info = pci_get_drvdata(par->pci_dev);32 int nlevel;33 34 /* Get and convert the value */35 /* No locking of bl_curve since we read a single value */36 nlevel = MIN_LEVEL + info->bl_curve[level] * LEVEL_STEP;37 38 if (nlevel < 0)39 nlevel = 0;40 else if (nlevel < MIN_LEVEL)41 nlevel = MIN_LEVEL;42 else if (nlevel > MAX_LEVEL)43 nlevel = MAX_LEVEL;44 45 return nlevel;46}47 48static int nvidia_bl_update_status(struct backlight_device *bd)49{50 struct nvidia_par *par = bl_get_data(bd);51 u32 tmp_pcrt, tmp_pmc, fpcontrol;52 int level = backlight_get_brightness(bd);53 54 if (!par->FlatPanel)55 return 0;56 57 tmp_pmc = NV_RD32(par->PMC, 0x10F0) & 0x0000FFFF;58 tmp_pcrt = NV_RD32(par->PCRTC0, 0x081C) & 0xFFFFFFFC;59 fpcontrol = NV_RD32(par->PRAMDAC, 0x0848) & 0xCFFFFFCC;60 61 if (level > 0) {62 tmp_pcrt |= 0x1;63 tmp_pmc |= (1 << 31); /* backlight bit */64 tmp_pmc |= nvidia_bl_get_level_brightness(par, level) << 16;65 fpcontrol |= par->fpSyncs;66 } else67 fpcontrol |= 0x20000022;68 69 NV_WR32(par->PCRTC0, 0x081C, tmp_pcrt);70 NV_WR32(par->PMC, 0x10F0, tmp_pmc);71 NV_WR32(par->PRAMDAC, 0x848, fpcontrol);72 73 return 0;74}75 76static const struct backlight_ops nvidia_bl_ops = {77 .update_status = nvidia_bl_update_status,78};79 80void nvidia_bl_init(struct nvidia_par *par)81{82 struct backlight_properties props;83 struct fb_info *info = pci_get_drvdata(par->pci_dev);84 struct backlight_device *bd;85 char name[12];86 87 if (!par->FlatPanel)88 return;89 90#ifdef CONFIG_PMAC_BACKLIGHT91 if (!machine_is(powermac) ||92 !pmac_has_backlight_type("mnca"))93 return;94#endif95 96 snprintf(name, sizeof(name), "nvidiabl%d", info->node);97 98 memset(&props, 0, sizeof(struct backlight_properties));99 props.type = BACKLIGHT_RAW;100 props.max_brightness = FB_BACKLIGHT_LEVELS - 1;101 bd = backlight_device_register(name, info->device, par, &nvidia_bl_ops,102 &props);103 if (IS_ERR(bd)) {104 info->bl_dev = NULL;105 printk(KERN_WARNING "nvidia: Backlight registration failed\n");106 goto error;107 }108 109 info->bl_dev = bd;110 fb_bl_default_curve(info, 0,111 0x158 * FB_BACKLIGHT_MAX / MAX_LEVEL,112 0x534 * FB_BACKLIGHT_MAX / MAX_LEVEL);113 114 bd->props.brightness = bd->props.max_brightness;115 bd->props.power = FB_BLANK_UNBLANK;116 backlight_update_status(bd);117 118 printk("nvidia: Backlight initialized (%s)\n", name);119 120error:121 return;122}123 124void nvidia_bl_exit(struct nvidia_par *par)125{126 struct fb_info *info = pci_get_drvdata(par->pci_dev);127 struct backlight_device *bd = info->bl_dev;128 129 backlight_device_unregister(bd);130 printk("nvidia: Backlight unloaded\n");131}132