Thomas Gleixner | 2b27bdc | 2019-05-29 16:57:50 -0700 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-only |
Jin Park | 4b0d711 | 2011-06-29 23:06:51 +0900 | [diff] [blame] | 2 | /* |
| 3 | * linux/drivers/video/backlight/aat2870_bl.c |
| 4 | * |
| 5 | * Copyright (c) 2011, NVIDIA Corporation. |
| 6 | * Author: Jin Park <jinyoungp@nvidia.com> |
Jin Park | 4b0d711 | 2011-06-29 23:06:51 +0900 | [diff] [blame] | 7 | */ |
| 8 | |
| 9 | #include <linux/module.h> |
| 10 | #include <linux/kernel.h> |
| 11 | #include <linux/init.h> |
| 12 | #include <linux/platform_device.h> |
| 13 | #include <linux/mutex.h> |
| 14 | #include <linux/delay.h> |
| 15 | #include <linux/fb.h> |
| 16 | #include <linux/backlight.h> |
| 17 | #include <linux/mfd/aat2870.h> |
| 18 | |
| 19 | struct aat2870_bl_driver_data { |
| 20 | struct platform_device *pdev; |
| 21 | struct backlight_device *bd; |
| 22 | |
| 23 | int channels; |
| 24 | int max_current; |
| 25 | int brightness; /* current brightness */ |
| 26 | }; |
| 27 | |
| 28 | static inline int aat2870_brightness(struct aat2870_bl_driver_data *aat2870_bl, |
| 29 | int brightness) |
| 30 | { |
| 31 | struct backlight_device *bd = aat2870_bl->bd; |
| 32 | int val; |
| 33 | |
Axel Lin | 5d6f921 | 2011-08-03 16:21:17 -0700 | [diff] [blame] | 34 | val = brightness * (aat2870_bl->max_current - 1); |
Jin Park | 4b0d711 | 2011-06-29 23:06:51 +0900 | [diff] [blame] | 35 | val /= bd->props.max_brightness; |
| 36 | |
| 37 | return val; |
| 38 | } |
| 39 | |
| 40 | static inline int aat2870_bl_enable(struct aat2870_bl_driver_data *aat2870_bl) |
| 41 | { |
| 42 | struct aat2870_data *aat2870 |
| 43 | = dev_get_drvdata(aat2870_bl->pdev->dev.parent); |
| 44 | |
| 45 | return aat2870->write(aat2870, AAT2870_BL_CH_EN, |
| 46 | (u8)aat2870_bl->channels); |
| 47 | } |
| 48 | |
| 49 | static inline int aat2870_bl_disable(struct aat2870_bl_driver_data *aat2870_bl) |
| 50 | { |
| 51 | struct aat2870_data *aat2870 |
| 52 | = dev_get_drvdata(aat2870_bl->pdev->dev.parent); |
| 53 | |
| 54 | return aat2870->write(aat2870, AAT2870_BL_CH_EN, 0x0); |
| 55 | } |
| 56 | |
Jin Park | 4b0d711 | 2011-06-29 23:06:51 +0900 | [diff] [blame] | 57 | static int aat2870_bl_update_status(struct backlight_device *bd) |
| 58 | { |
Jingoo Han | 76cb259 | 2013-02-21 16:43:44 -0800 | [diff] [blame] | 59 | struct aat2870_bl_driver_data *aat2870_bl = bl_get_data(bd); |
Jin Park | 4b0d711 | 2011-06-29 23:06:51 +0900 | [diff] [blame] | 60 | struct aat2870_data *aat2870 = |
| 61 | dev_get_drvdata(aat2870_bl->pdev->dev.parent); |
| 62 | int brightness = bd->props.brightness; |
| 63 | int ret; |
| 64 | |
| 65 | if ((brightness < 0) || (bd->props.max_brightness < brightness)) { |
| 66 | dev_err(&bd->dev, "invalid brightness, %d\n", brightness); |
| 67 | return -EINVAL; |
| 68 | } |
| 69 | |
| 70 | dev_dbg(&bd->dev, "brightness=%d, power=%d, state=%d\n", |
| 71 | bd->props.brightness, bd->props.power, bd->props.state); |
| 72 | |
| 73 | if ((bd->props.power != FB_BLANK_UNBLANK) || |
| 74 | (bd->props.state & BL_CORE_FBBLANK) || |
| 75 | (bd->props.state & BL_CORE_SUSPENDED)) |
| 76 | brightness = 0; |
| 77 | |
| 78 | ret = aat2870->write(aat2870, AAT2870_BLM, |
| 79 | (u8)aat2870_brightness(aat2870_bl, brightness)); |
| 80 | if (ret < 0) |
| 81 | return ret; |
| 82 | |
| 83 | if (brightness == 0) { |
| 84 | ret = aat2870_bl_disable(aat2870_bl); |
| 85 | if (ret < 0) |
| 86 | return ret; |
| 87 | } else if (aat2870_bl->brightness == 0) { |
| 88 | ret = aat2870_bl_enable(aat2870_bl); |
| 89 | if (ret < 0) |
| 90 | return ret; |
| 91 | } |
| 92 | |
| 93 | aat2870_bl->brightness = brightness; |
| 94 | |
| 95 | return 0; |
| 96 | } |
| 97 | |
| 98 | static int aat2870_bl_check_fb(struct backlight_device *bd, struct fb_info *fi) |
| 99 | { |
| 100 | return 1; |
| 101 | } |
| 102 | |
| 103 | static const struct backlight_ops aat2870_bl_ops = { |
| 104 | .options = BL_CORE_SUSPENDRESUME, |
Jin Park | 4b0d711 | 2011-06-29 23:06:51 +0900 | [diff] [blame] | 105 | .update_status = aat2870_bl_update_status, |
| 106 | .check_fb = aat2870_bl_check_fb, |
| 107 | }; |
| 108 | |
| 109 | static int aat2870_bl_probe(struct platform_device *pdev) |
| 110 | { |
Jingoo Han | c512794c | 2013-11-12 15:09:04 -0800 | [diff] [blame] | 111 | struct aat2870_bl_platform_data *pdata = dev_get_platdata(&pdev->dev); |
Jin Park | 4b0d711 | 2011-06-29 23:06:51 +0900 | [diff] [blame] | 112 | struct aat2870_bl_driver_data *aat2870_bl; |
| 113 | struct backlight_device *bd; |
| 114 | struct backlight_properties props; |
| 115 | int ret = 0; |
| 116 | |
| 117 | if (!pdata) { |
| 118 | dev_err(&pdev->dev, "No platform data\n"); |
| 119 | ret = -ENXIO; |
| 120 | goto out; |
| 121 | } |
| 122 | |
| 123 | if (pdev->id != AAT2870_ID_BL) { |
| 124 | dev_err(&pdev->dev, "Invalid device ID, %d\n", pdev->id); |
| 125 | ret = -EINVAL; |
| 126 | goto out; |
| 127 | } |
| 128 | |
Julia Lawall | ce96922 | 2012-03-23 15:02:00 -0700 | [diff] [blame] | 129 | aat2870_bl = devm_kzalloc(&pdev->dev, |
| 130 | sizeof(struct aat2870_bl_driver_data), |
| 131 | GFP_KERNEL); |
Jin Park | 4b0d711 | 2011-06-29 23:06:51 +0900 | [diff] [blame] | 132 | if (!aat2870_bl) { |
Jin Park | 4b0d711 | 2011-06-29 23:06:51 +0900 | [diff] [blame] | 133 | ret = -ENOMEM; |
| 134 | goto out; |
| 135 | } |
| 136 | |
| 137 | memset(&props, 0, sizeof(struct backlight_properties)); |
| 138 | |
| 139 | props.type = BACKLIGHT_RAW; |
Jingoo Han | c7a2bf3 | 2013-11-12 15:09:06 -0800 | [diff] [blame] | 140 | bd = devm_backlight_device_register(&pdev->dev, "aat2870-backlight", |
| 141 | &pdev->dev, aat2870_bl, &aat2870_bl_ops, |
| 142 | &props); |
Axel Lin | 4c4dd90 | 2011-08-03 16:21:16 -0700 | [diff] [blame] | 143 | if (IS_ERR(bd)) { |
Jin Park | 4b0d711 | 2011-06-29 23:06:51 +0900 | [diff] [blame] | 144 | dev_err(&pdev->dev, |
| 145 | "Failed allocate memory for backlight device\n"); |
Axel Lin | 4c4dd90 | 2011-08-03 16:21:16 -0700 | [diff] [blame] | 146 | ret = PTR_ERR(bd); |
Julia Lawall | ce96922 | 2012-03-23 15:02:00 -0700 | [diff] [blame] | 147 | goto out; |
Jin Park | 4b0d711 | 2011-06-29 23:06:51 +0900 | [diff] [blame] | 148 | } |
| 149 | |
| 150 | aat2870_bl->pdev = pdev; |
| 151 | platform_set_drvdata(pdev, aat2870_bl); |
| 152 | |
| 153 | aat2870_bl->bd = bd; |
| 154 | |
| 155 | if (pdata->channels > 0) |
| 156 | aat2870_bl->channels = pdata->channels; |
| 157 | else |
| 158 | aat2870_bl->channels = AAT2870_BL_CH_ALL; |
| 159 | |
Axel Lin | 5d6f921 | 2011-08-03 16:21:17 -0700 | [diff] [blame] | 160 | if (pdata->max_current > 0) |
Jin Park | 4b0d711 | 2011-06-29 23:06:51 +0900 | [diff] [blame] | 161 | aat2870_bl->max_current = pdata->max_current; |
| 162 | else |
| 163 | aat2870_bl->max_current = AAT2870_CURRENT_27_9; |
| 164 | |
| 165 | if (pdata->max_brightness > 0) |
| 166 | bd->props.max_brightness = pdata->max_brightness; |
| 167 | else |
| 168 | bd->props.max_brightness = 255; |
| 169 | |
| 170 | aat2870_bl->brightness = 0; |
| 171 | bd->props.power = FB_BLANK_UNBLANK; |
| 172 | bd->props.brightness = bd->props.max_brightness; |
| 173 | |
| 174 | ret = aat2870_bl_update_status(bd); |
| 175 | if (ret < 0) { |
| 176 | dev_err(&pdev->dev, "Failed to initialize\n"); |
Jingoo Han | c7a2bf3 | 2013-11-12 15:09:06 -0800 | [diff] [blame] | 177 | return ret; |
Jin Park | 4b0d711 | 2011-06-29 23:06:51 +0900 | [diff] [blame] | 178 | } |
| 179 | |
| 180 | return 0; |
| 181 | |
Jin Park | 4b0d711 | 2011-06-29 23:06:51 +0900 | [diff] [blame] | 182 | out: |
| 183 | return ret; |
| 184 | } |
| 185 | |
| 186 | static int aat2870_bl_remove(struct platform_device *pdev) |
| 187 | { |
| 188 | struct aat2870_bl_driver_data *aat2870_bl = platform_get_drvdata(pdev); |
| 189 | struct backlight_device *bd = aat2870_bl->bd; |
| 190 | |
| 191 | bd->props.power = FB_BLANK_POWERDOWN; |
| 192 | bd->props.brightness = 0; |
| 193 | backlight_update_status(bd); |
| 194 | |
Jin Park | 4b0d711 | 2011-06-29 23:06:51 +0900 | [diff] [blame] | 195 | return 0; |
| 196 | } |
| 197 | |
| 198 | static struct platform_driver aat2870_bl_driver = { |
| 199 | .driver = { |
| 200 | .name = "aat2870-backlight", |
Jin Park | 4b0d711 | 2011-06-29 23:06:51 +0900 | [diff] [blame] | 201 | }, |
| 202 | .probe = aat2870_bl_probe, |
| 203 | .remove = aat2870_bl_remove, |
| 204 | }; |
| 205 | |
| 206 | static int __init aat2870_bl_init(void) |
| 207 | { |
| 208 | return platform_driver_register(&aat2870_bl_driver); |
| 209 | } |
| 210 | subsys_initcall(aat2870_bl_init); |
| 211 | |
| 212 | static void __exit aat2870_bl_exit(void) |
| 213 | { |
| 214 | platform_driver_unregister(&aat2870_bl_driver); |
| 215 | } |
| 216 | module_exit(aat2870_bl_exit); |
| 217 | |
| 218 | MODULE_DESCRIPTION("AnalogicTech AAT2870 Backlight"); |
| 219 | MODULE_LICENSE("GPL"); |
| 220 | MODULE_AUTHOR("Jin Park <jinyoungp@nvidia.com>"); |