|
| 1 | +/* |
| 2 | + * INT3406 thermal driver for display participant device |
| 3 | + * |
| 4 | + * Copyright (C) 2016, Intel Corporation |
| 5 | + * Authors: Aaron Lu <[email protected]> |
| 6 | + * |
| 7 | + * This program is free software; you can redistribute it and/or modify |
| 8 | + * it under the terms of the GNU General Public License version 2 as |
| 9 | + * published by the Free Software Foundation. |
| 10 | + * |
| 11 | + */ |
| 12 | + |
| 13 | +#include <linux/module.h> |
| 14 | +#include <linux/platform_device.h> |
| 15 | +#include <linux/acpi.h> |
| 16 | +#include <linux/backlight.h> |
| 17 | +#include <linux/thermal.h> |
| 18 | +#include <acpi/video.h> |
| 19 | + |
| 20 | +#define INT3406_BRIGHTNESS_LIMITS_CHANGED 0x80 |
| 21 | + |
| 22 | +struct int3406_thermal_data { |
| 23 | + int upper_limit; |
| 24 | + int upper_limit_index; |
| 25 | + int lower_limit; |
| 26 | + int lower_limit_index; |
| 27 | + acpi_handle handle; |
| 28 | + struct acpi_video_device_brightness *br; |
| 29 | + struct backlight_device *raw_bd; |
| 30 | + struct thermal_cooling_device *cooling_dev; |
| 31 | +}; |
| 32 | + |
| 33 | +static int int3406_thermal_to_raw(int level, struct int3406_thermal_data *d) |
| 34 | +{ |
| 35 | + int max_level = d->br->levels[d->br->count - 1]; |
| 36 | + int raw_max = d->raw_bd->props.max_brightness; |
| 37 | + |
| 38 | + return level * raw_max / max_level; |
| 39 | +} |
| 40 | + |
| 41 | +static int int3406_thermal_to_acpi(int level, struct int3406_thermal_data *d) |
| 42 | +{ |
| 43 | + int raw_max = d->raw_bd->props.max_brightness; |
| 44 | + int max_level = d->br->levels[d->br->count - 1]; |
| 45 | + |
| 46 | + return level * max_level / raw_max; |
| 47 | +} |
| 48 | + |
| 49 | +static int |
| 50 | +int3406_thermal_get_max_state(struct thermal_cooling_device *cooling_dev, |
| 51 | + unsigned long *state) |
| 52 | +{ |
| 53 | + struct int3406_thermal_data *d = cooling_dev->devdata; |
| 54 | + int index = d->lower_limit_index ? d->lower_limit_index : 2; |
| 55 | + |
| 56 | + *state = d->br->count - 1 - index; |
| 57 | + return 0; |
| 58 | +} |
| 59 | + |
| 60 | +static int |
| 61 | +int3406_thermal_set_cur_state(struct thermal_cooling_device *cooling_dev, |
| 62 | + unsigned long state) |
| 63 | +{ |
| 64 | + struct int3406_thermal_data *d = cooling_dev->devdata; |
| 65 | + int level, raw_level; |
| 66 | + |
| 67 | + if (state > d->br->count - 3) |
| 68 | + return -EINVAL; |
| 69 | + |
| 70 | + state = d->br->count - 1 - state; |
| 71 | + level = d->br->levels[state]; |
| 72 | + |
| 73 | + if ((d->upper_limit && level > d->upper_limit) || |
| 74 | + (d->lower_limit && level < d->lower_limit)) |
| 75 | + return -EINVAL; |
| 76 | + |
| 77 | + raw_level = int3406_thermal_to_raw(level, d); |
| 78 | + return backlight_device_set_brightness(d->raw_bd, raw_level); |
| 79 | +} |
| 80 | + |
| 81 | +static int |
| 82 | +int3406_thermal_get_cur_state(struct thermal_cooling_device *cooling_dev, |
| 83 | + unsigned long *state) |
| 84 | +{ |
| 85 | + struct int3406_thermal_data *d = cooling_dev->devdata; |
| 86 | + int raw_level, level, i; |
| 87 | + int *levels = d->br->levels; |
| 88 | + |
| 89 | + raw_level = d->raw_bd->props.brightness; |
| 90 | + level = int3406_thermal_to_acpi(raw_level, d); |
| 91 | + |
| 92 | + /* |
| 93 | + * There is no 1:1 mapping between the firmware interface level with the |
| 94 | + * raw interface level, we will have to find one that is close enough. |
| 95 | + */ |
| 96 | + for (i = 2; i < d->br->count; i++) { |
| 97 | + if (level < levels[i]) { |
| 98 | + if (i == 2) |
| 99 | + break; |
| 100 | + if ((level - levels[i - 1]) < (levels[i] - level)) |
| 101 | + i--; |
| 102 | + break; |
| 103 | + } |
| 104 | + } |
| 105 | + |
| 106 | + *state = d->br->count - 1 - i; |
| 107 | + return 0; |
| 108 | +} |
| 109 | + |
| 110 | +static const struct thermal_cooling_device_ops video_cooling_ops = { |
| 111 | + .get_max_state = int3406_thermal_get_max_state, |
| 112 | + .get_cur_state = int3406_thermal_get_cur_state, |
| 113 | + .set_cur_state = int3406_thermal_set_cur_state, |
| 114 | +}; |
| 115 | + |
| 116 | +static int int3406_thermal_get_index(int *array, int nr, int value) |
| 117 | +{ |
| 118 | + int i; |
| 119 | + |
| 120 | + for (i = 0; i < nr; i++) { |
| 121 | + if (array[i] == value) |
| 122 | + break; |
| 123 | + } |
| 124 | + return i == nr ? -ENOENT : i; |
| 125 | +} |
| 126 | + |
| 127 | +static void int3406_thermal_get_limit(struct int3406_thermal_data *d) |
| 128 | +{ |
| 129 | + acpi_status status; |
| 130 | + unsigned long long lower_limit, upper_limit; |
| 131 | + int index; |
| 132 | + |
| 133 | + status = acpi_evaluate_integer(d->handle, "DDDL", NULL, &lower_limit); |
| 134 | + if (ACPI_SUCCESS(status)) { |
| 135 | + index = int3406_thermal_get_index(d->br->levels, d->br->count, |
| 136 | + lower_limit); |
| 137 | + if (index > 0) { |
| 138 | + d->lower_limit = (int)lower_limit; |
| 139 | + d->lower_limit_index = index; |
| 140 | + } |
| 141 | + } |
| 142 | + |
| 143 | + status = acpi_evaluate_integer(d->handle, "DDPC", NULL, &upper_limit); |
| 144 | + if (ACPI_SUCCESS(status)) { |
| 145 | + index = int3406_thermal_get_index(d->br->levels, d->br->count, |
| 146 | + upper_limit); |
| 147 | + if (index > 0) { |
| 148 | + d->upper_limit = (int)upper_limit; |
| 149 | + d->upper_limit_index = index; |
| 150 | + } |
| 151 | + } |
| 152 | +} |
| 153 | + |
| 154 | +static void int3406_notify(acpi_handle handle, u32 event, void *data) |
| 155 | +{ |
| 156 | + if (event == INT3406_BRIGHTNESS_LIMITS_CHANGED) |
| 157 | + int3406_thermal_get_limit(data); |
| 158 | +} |
| 159 | + |
| 160 | +static int int3406_thermal_probe(struct platform_device *pdev) |
| 161 | +{ |
| 162 | + struct acpi_device *adev = ACPI_COMPANION(&pdev->dev); |
| 163 | + struct int3406_thermal_data *d; |
| 164 | + struct backlight_device *bd; |
| 165 | + int ret; |
| 166 | + |
| 167 | + if (!ACPI_HANDLE(&pdev->dev)) |
| 168 | + return -ENODEV; |
| 169 | + |
| 170 | + d = devm_kzalloc(&pdev->dev, sizeof(*d), GFP_KERNEL); |
| 171 | + if (!d) |
| 172 | + return -ENOMEM; |
| 173 | + d->handle = ACPI_HANDLE(&pdev->dev); |
| 174 | + |
| 175 | + bd = backlight_device_get_by_type(BACKLIGHT_RAW); |
| 176 | + if (!bd) |
| 177 | + return -ENODEV; |
| 178 | + d->raw_bd = bd; |
| 179 | + |
| 180 | + ret = acpi_video_get_levels(ACPI_COMPANION(&pdev->dev), &d->br); |
| 181 | + if (ret) |
| 182 | + return ret; |
| 183 | + |
| 184 | + int3406_thermal_get_limit(d); |
| 185 | + |
| 186 | + d->cooling_dev = thermal_cooling_device_register(acpi_device_bid(adev), |
| 187 | + d, &video_cooling_ops); |
| 188 | + if (IS_ERR(d->cooling_dev)) |
| 189 | + goto err; |
| 190 | + |
| 191 | + ret = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY, |
| 192 | + int3406_notify, d); |
| 193 | + if (ret) |
| 194 | + goto err_cdev; |
| 195 | + |
| 196 | + platform_set_drvdata(pdev, d); |
| 197 | + |
| 198 | + return 0; |
| 199 | + |
| 200 | +err_cdev: |
| 201 | + thermal_cooling_device_unregister(d->cooling_dev); |
| 202 | +err: |
| 203 | + kfree(d->br); |
| 204 | + return -ENODEV; |
| 205 | +} |
| 206 | + |
| 207 | +static int int3406_thermal_remove(struct platform_device *pdev) |
| 208 | +{ |
| 209 | + struct int3406_thermal_data *d = platform_get_drvdata(pdev); |
| 210 | + |
| 211 | + thermal_cooling_device_unregister(d->cooling_dev); |
| 212 | + kfree(d->br); |
| 213 | + return 0; |
| 214 | +} |
| 215 | + |
| 216 | +static const struct acpi_device_id int3406_thermal_match[] = { |
| 217 | + {"INT3406", 0}, |
| 218 | + {} |
| 219 | +}; |
| 220 | + |
| 221 | +MODULE_DEVICE_TABLE(acpi, int3406_thermal_match); |
| 222 | + |
| 223 | +static struct platform_driver int3406_thermal_driver = { |
| 224 | + .probe = int3406_thermal_probe, |
| 225 | + .remove = int3406_thermal_remove, |
| 226 | + .driver = { |
| 227 | + .name = "int3406 thermal", |
| 228 | + .owner = THIS_MODULE, |
| 229 | + .acpi_match_table = int3406_thermal_match, |
| 230 | + }, |
| 231 | +}; |
| 232 | + |
| 233 | +module_platform_driver(int3406_thermal_driver); |
| 234 | + |
| 235 | +MODULE_DESCRIPTION("INT3406 Thermal driver"); |
| 236 | +MODULE_LICENSE("GPL v2"); |
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