kernel/swap/energy/lcd/maru.c

   1 /*
   2  *  Dynamic Binary Instrumentation Module based on KProbes
   3  *  energy/lcd/maru.c
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18  *
  19  * Copyright (C) Samsung Electronics, 2013
  20  *
  21  * 2013         Vyacheslav Cherkashin <v.cherkashin@samsung.com>
  22  *
  23  */
  24
  25
  26 #include <kprobe/swap_kprobes.h>
  27 #include <linux/backlight.h>
  28 #include "lcd_base.h"
  29
  30
  31
  32 static const char path_backlight[]      =
  33         "/sys/class/backlight/emulator/brightness";
  34 static const char path_backlight_min[]  =
  35         "/sys/class/backlight/emulator/min_brightness";
  36 static const char path_backlight_max[]  =
  37         "/sys/class/backlight/emulator/max_brightness";
  38 static const char path_power[]          =
  39         "/sys/class/lcd/emulator/lcd_power";
  40
  41 static const char * const all_path[] = {
  42         path_backlight,
  43         path_backlight_min,
  44         path_backlight_max,
  45         path_power
  46 };
  47
  48 enum {
  49         all_path_cnt = sizeof(all_path) / sizeof(char *)
  50 };
  51
  52
  53 static int maru_check(struct lcd_ops *ops)
  54 {
  55         int i;
  56
  57         for (i = 0; i < all_path_cnt; ++i) {
  58                 int ret = read_val(all_path[i]);
  59
  60                 if (IS_ERR_VALUE(ret))
  61                         return 0;
  62         }
  63
  64         return 1;
  65 }
  66
  67 static unsigned long maru_get_parameter(struct lcd_ops *ops,
  68                                         enum lcd_parameter_type type)
  69 {
  70         switch (type) {
  71         case LPD_MIN_BRIGHTNESS:
  72                 return read_val(path_backlight_min);
  73         case LPD_MAX_BRIGHTNESS:
  74                 return read_val(path_backlight_max);
  75         case LPD_BRIGHTNESS:
  76                 return read_val(path_backlight);
  77         case LPD_POWER:
  78                 return read_val(path_power);
  79         default:
  80                 return -EINVAL;
  81         }
  82 }
  83
  84
  85
  86
  87
  88 static int entry_handler_set_backlight(struct kretprobe_instance *ri,
  89                                        struct pt_regs *regs);
  90 static int ret_handler_set_backlight(struct kretprobe_instance *ri,
  91                                      struct pt_regs *regs);
  92
  93 static struct kretprobe set_backlight_krp = {
  94         .kp.symbol_name = "marubl_send_intensity",
  95         .entry_handler = entry_handler_set_backlight,
  96         .handler = ret_handler_set_backlight,
  97         .data_size = sizeof(int)
  98 };
  99
 100
 101
 102
 103
 104 static int maru_set(struct lcd_ops *ops)
 105 {
 106         return swap_register_kretprobe(&set_backlight_krp);
 107 }
 108
 109 static int maru_unset(struct lcd_ops *ops)
 110 {
 111         swap_unregister_kretprobe(&set_backlight_krp);
 112         return 0;
 113 }
 114
 115 static struct lcd_ops maru_ops = {
 116         .name = "maru",
 117         .check = maru_check,
 118         .set = maru_set,
 119         .unset = maru_unset,
 120         .get = maru_get_parameter
 121 };
 122
 123 struct lcd_ops *LCD_MAKE_FNAME(maru)(void)
 124 {
 125         return &maru_ops;
 126 }
 127
 128
 129
 130
 131
 132 static int entry_handler_set_backlight(struct kretprobe_instance *ri,
 133                                        struct pt_regs *regs)
 134 {
 135         int *brightness = (int *)ri->data;
 136         struct backlight_device *bd;
 137
 138         bd = (struct backlight_device *)swap_get_karg(regs, 0);
 139         *brightness = bd->props.brightness;
 140
 141         return 0;
 142 }
 143
 144 static int ret_handler_set_backlight(struct kretprobe_instance *ri,
 145                                      struct pt_regs *regs)
 146 {
 147         int ret = regs_return_value(regs);
 148         int *brightness = (int *)ri->data;
 149
 150         if (!ret && maru_ops.notifier)
 151                 maru_ops.notifier(&maru_ops, LAT_BRIGHTNESS,
 152                                   (void *)*brightness);
 153
 154         return 0;
 155 }