Commit | Line | Data |
---|---|---|
2b27bdcc | 1 | // SPDX-License-Identifier: GPL-2.0-only |
4b0d711b JP |
2 | /* |
3 | * linux/drivers/video/backlight/aat2870_bl.c | |
4 | * | |
5 | * Copyright (c) 2011, NVIDIA Corporation. | |
6 | * Author: Jin Park <jinyoungp@nvidia.com> | |
4b0d711b JP |
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 | ||
5d6f921b | 34 | val = brightness * (aat2870_bl->max_current - 1); |
4b0d711b JP |
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 | ||
4b0d711b JP |
57 | static int aat2870_bl_update_status(struct backlight_device *bd) |
58 | { | |
76cb2598 | 59 | struct aat2870_bl_driver_data *aat2870_bl = bl_get_data(bd); |
4b0d711b JP |
60 | struct aat2870_data *aat2870 = |
61 | dev_get_drvdata(aat2870_bl->pdev->dev.parent); | |
32fb2588 | 62 | int brightness = backlight_get_brightness(bd); |
4b0d711b JP |
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 | ||
4b0d711b JP |
73 | ret = aat2870->write(aat2870, AAT2870_BLM, |
74 | (u8)aat2870_brightness(aat2870_bl, brightness)); | |
75 | if (ret < 0) | |
76 | return ret; | |
77 | ||
78 | if (brightness == 0) { | |
79 | ret = aat2870_bl_disable(aat2870_bl); | |
80 | if (ret < 0) | |
81 | return ret; | |
82 | } else if (aat2870_bl->brightness == 0) { | |
83 | ret = aat2870_bl_enable(aat2870_bl); | |
84 | if (ret < 0) | |
85 | return ret; | |
86 | } | |
87 | ||
88 | aat2870_bl->brightness = brightness; | |
89 | ||
90 | return 0; | |
91 | } | |
92 | ||
93 | static int aat2870_bl_check_fb(struct backlight_device *bd, struct fb_info *fi) | |
94 | { | |
95 | return 1; | |
96 | } | |
97 | ||
98 | static const struct backlight_ops aat2870_bl_ops = { | |
99 | .options = BL_CORE_SUSPENDRESUME, | |
4b0d711b JP |
100 | .update_status = aat2870_bl_update_status, |
101 | .check_fb = aat2870_bl_check_fb, | |
102 | }; | |
103 | ||
104 | static int aat2870_bl_probe(struct platform_device *pdev) | |
105 | { | |
c512794c | 106 | struct aat2870_bl_platform_data *pdata = dev_get_platdata(&pdev->dev); |
4b0d711b JP |
107 | struct aat2870_bl_driver_data *aat2870_bl; |
108 | struct backlight_device *bd; | |
109 | struct backlight_properties props; | |
110 | int ret = 0; | |
111 | ||
112 | if (!pdata) { | |
113 | dev_err(&pdev->dev, "No platform data\n"); | |
114 | ret = -ENXIO; | |
115 | goto out; | |
116 | } | |
117 | ||
118 | if (pdev->id != AAT2870_ID_BL) { | |
119 | dev_err(&pdev->dev, "Invalid device ID, %d\n", pdev->id); | |
120 | ret = -EINVAL; | |
121 | goto out; | |
122 | } | |
123 | ||
ce969228 JL |
124 | aat2870_bl = devm_kzalloc(&pdev->dev, |
125 | sizeof(struct aat2870_bl_driver_data), | |
126 | GFP_KERNEL); | |
4b0d711b | 127 | if (!aat2870_bl) { |
4b0d711b JP |
128 | ret = -ENOMEM; |
129 | goto out; | |
130 | } | |
131 | ||
132 | memset(&props, 0, sizeof(struct backlight_properties)); | |
133 | ||
134 | props.type = BACKLIGHT_RAW; | |
c7a2bf3b JH |
135 | bd = devm_backlight_device_register(&pdev->dev, "aat2870-backlight", |
136 | &pdev->dev, aat2870_bl, &aat2870_bl_ops, | |
137 | &props); | |
4c4dd903 | 138 | if (IS_ERR(bd)) { |
4b0d711b JP |
139 | dev_err(&pdev->dev, |
140 | "Failed allocate memory for backlight device\n"); | |
4c4dd903 | 141 | ret = PTR_ERR(bd); |
ce969228 | 142 | goto out; |
4b0d711b JP |
143 | } |
144 | ||
145 | aat2870_bl->pdev = pdev; | |
146 | platform_set_drvdata(pdev, aat2870_bl); | |
147 | ||
148 | aat2870_bl->bd = bd; | |
149 | ||
150 | if (pdata->channels > 0) | |
151 | aat2870_bl->channels = pdata->channels; | |
152 | else | |
153 | aat2870_bl->channels = AAT2870_BL_CH_ALL; | |
154 | ||
5d6f921b | 155 | if (pdata->max_current > 0) |
4b0d711b JP |
156 | aat2870_bl->max_current = pdata->max_current; |
157 | else | |
158 | aat2870_bl->max_current = AAT2870_CURRENT_27_9; | |
159 | ||
160 | if (pdata->max_brightness > 0) | |
161 | bd->props.max_brightness = pdata->max_brightness; | |
162 | else | |
163 | bd->props.max_brightness = 255; | |
164 | ||
165 | aat2870_bl->brightness = 0; | |
166 | bd->props.power = FB_BLANK_UNBLANK; | |
167 | bd->props.brightness = bd->props.max_brightness; | |
168 | ||
169 | ret = aat2870_bl_update_status(bd); | |
170 | if (ret < 0) { | |
171 | dev_err(&pdev->dev, "Failed to initialize\n"); | |
c7a2bf3b | 172 | return ret; |
4b0d711b JP |
173 | } |
174 | ||
175 | return 0; | |
176 | ||
4b0d711b JP |
177 | out: |
178 | return ret; | |
179 | } | |
180 | ||
8b339caf | 181 | static void aat2870_bl_remove(struct platform_device *pdev) |
4b0d711b JP |
182 | { |
183 | struct aat2870_bl_driver_data *aat2870_bl = platform_get_drvdata(pdev); | |
184 | struct backlight_device *bd = aat2870_bl->bd; | |
185 | ||
186 | bd->props.power = FB_BLANK_POWERDOWN; | |
187 | bd->props.brightness = 0; | |
188 | backlight_update_status(bd); | |
4b0d711b JP |
189 | } |
190 | ||
191 | static struct platform_driver aat2870_bl_driver = { | |
192 | .driver = { | |
193 | .name = "aat2870-backlight", | |
4b0d711b JP |
194 | }, |
195 | .probe = aat2870_bl_probe, | |
8b339caf | 196 | .remove_new = aat2870_bl_remove, |
4b0d711b JP |
197 | }; |
198 | ||
199 | static int __init aat2870_bl_init(void) | |
200 | { | |
201 | return platform_driver_register(&aat2870_bl_driver); | |
202 | } | |
203 | subsys_initcall(aat2870_bl_init); | |
204 | ||
205 | static void __exit aat2870_bl_exit(void) | |
206 | { | |
207 | platform_driver_unregister(&aat2870_bl_driver); | |
208 | } | |
209 | module_exit(aat2870_bl_exit); | |
210 | ||
211 | MODULE_DESCRIPTION("AnalogicTech AAT2870 Backlight"); | |
212 | MODULE_LICENSE("GPL"); | |
213 | MODULE_AUTHOR("Jin Park <jinyoungp@nvidia.com>"); |