1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Backlight driver for OMAP based boards. |
4 | * |
5 | * Copyright (c) 2006 Andrzej Zaborowski <balrog@zabor.org> |
6 | */ |
7 | |
8 | #include <linux/module.h> |
9 | #include <linux/kernel.h> |
10 | #include <linux/init.h> |
11 | #include <linux/platform_device.h> |
12 | #include <linux/fb.h> |
13 | #include <linux/backlight.h> |
14 | #include <linux/slab.h> |
15 | #include <linux/platform_data/omap1_bl.h> |
16 | |
17 | #include <linux/soc/ti/omap1-io.h> |
18 | #include <linux/soc/ti/omap1-mux.h> |
19 | |
20 | #define OMAPBL_MAX_INTENSITY 0xff |
21 | |
22 | struct omap_backlight { |
23 | int powermode; |
24 | int current_intensity; |
25 | |
26 | struct device *dev; |
27 | struct omap_backlight_config *pdata; |
28 | }; |
29 | |
30 | static inline void omapbl_send_intensity(int intensity) |
31 | { |
32 | omap_writeb(v: intensity, OMAP_PWL_ENABLE); |
33 | } |
34 | |
35 | static inline void omapbl_send_enable(int enable) |
36 | { |
37 | omap_writeb(v: enable, OMAP_PWL_CLK_ENABLE); |
38 | } |
39 | |
40 | static void omapbl_blank(struct omap_backlight *bl, int mode) |
41 | { |
42 | if (bl->pdata->set_power) |
43 | bl->pdata->set_power(bl->dev, mode); |
44 | |
45 | switch (mode) { |
46 | case FB_BLANK_NORMAL: |
47 | case FB_BLANK_VSYNC_SUSPEND: |
48 | case FB_BLANK_HSYNC_SUSPEND: |
49 | case FB_BLANK_POWERDOWN: |
50 | omapbl_send_intensity(intensity: 0); |
51 | omapbl_send_enable(enable: 0); |
52 | break; |
53 | |
54 | case FB_BLANK_UNBLANK: |
55 | omapbl_send_intensity(intensity: bl->current_intensity); |
56 | omapbl_send_enable(enable: 1); |
57 | break; |
58 | } |
59 | } |
60 | |
61 | #ifdef CONFIG_PM_SLEEP |
62 | static int omapbl_suspend(struct device *dev) |
63 | { |
64 | struct backlight_device *bl_dev = dev_get_drvdata(dev); |
65 | struct omap_backlight *bl = bl_get_data(bl_dev); |
66 | |
67 | omapbl_blank(bl, mode: FB_BLANK_POWERDOWN); |
68 | return 0; |
69 | } |
70 | |
71 | static int omapbl_resume(struct device *dev) |
72 | { |
73 | struct backlight_device *bl_dev = dev_get_drvdata(dev); |
74 | struct omap_backlight *bl = bl_get_data(bl_dev); |
75 | |
76 | omapbl_blank(bl, mode: bl->powermode); |
77 | return 0; |
78 | } |
79 | #endif |
80 | |
81 | static int omapbl_set_power(struct backlight_device *dev, int state) |
82 | { |
83 | struct omap_backlight *bl = bl_get_data(bl_dev: dev); |
84 | |
85 | omapbl_blank(bl, mode: state); |
86 | bl->powermode = state; |
87 | |
88 | return 0; |
89 | } |
90 | |
91 | static int omapbl_update_status(struct backlight_device *dev) |
92 | { |
93 | struct omap_backlight *bl = bl_get_data(bl_dev: dev); |
94 | |
95 | if (bl->current_intensity != dev->props.brightness) { |
96 | if (bl->powermode == FB_BLANK_UNBLANK) |
97 | omapbl_send_intensity(intensity: dev->props.brightness); |
98 | bl->current_intensity = dev->props.brightness; |
99 | } |
100 | |
101 | if (dev->props.fb_blank != bl->powermode) |
102 | omapbl_set_power(dev, state: dev->props.fb_blank); |
103 | |
104 | return 0; |
105 | } |
106 | |
107 | static int omapbl_get_intensity(struct backlight_device *dev) |
108 | { |
109 | struct omap_backlight *bl = bl_get_data(bl_dev: dev); |
110 | |
111 | return bl->current_intensity; |
112 | } |
113 | |
114 | static const struct backlight_ops omapbl_ops = { |
115 | .get_brightness = omapbl_get_intensity, |
116 | .update_status = omapbl_update_status, |
117 | }; |
118 | |
119 | static int omapbl_probe(struct platform_device *pdev) |
120 | { |
121 | struct backlight_properties props; |
122 | struct backlight_device *dev; |
123 | struct omap_backlight *bl; |
124 | struct omap_backlight_config *pdata = dev_get_platdata(dev: &pdev->dev); |
125 | |
126 | if (!pdata) |
127 | return -ENXIO; |
128 | |
129 | bl = devm_kzalloc(dev: &pdev->dev, size: sizeof(struct omap_backlight), |
130 | GFP_KERNEL); |
131 | if (unlikely(!bl)) |
132 | return -ENOMEM; |
133 | |
134 | memset(&props, 0, sizeof(struct backlight_properties)); |
135 | props.type = BACKLIGHT_RAW; |
136 | props.max_brightness = OMAPBL_MAX_INTENSITY; |
137 | dev = devm_backlight_device_register(dev: &pdev->dev, name: "omap-bl" , parent: &pdev->dev, |
138 | devdata: bl, ops: &omapbl_ops, props: &props); |
139 | if (IS_ERR(ptr: dev)) |
140 | return PTR_ERR(ptr: dev); |
141 | |
142 | bl->powermode = FB_BLANK_POWERDOWN; |
143 | bl->current_intensity = 0; |
144 | |
145 | bl->pdata = pdata; |
146 | bl->dev = &pdev->dev; |
147 | |
148 | platform_set_drvdata(pdev, data: dev); |
149 | |
150 | omap_cfg_reg(reg_cfg: PWL); /* Conflicts with UART3 */ |
151 | |
152 | dev->props.fb_blank = FB_BLANK_UNBLANK; |
153 | dev->props.brightness = pdata->default_intensity; |
154 | omapbl_update_status(dev); |
155 | |
156 | dev_info(&pdev->dev, "OMAP LCD backlight initialised\n" ); |
157 | |
158 | return 0; |
159 | } |
160 | |
161 | static SIMPLE_DEV_PM_OPS(omapbl_pm_ops, omapbl_suspend, omapbl_resume); |
162 | |
163 | static struct platform_driver omapbl_driver = { |
164 | .probe = omapbl_probe, |
165 | .driver = { |
166 | .name = "omap-bl" , |
167 | .pm = &omapbl_pm_ops, |
168 | }, |
169 | }; |
170 | |
171 | module_platform_driver(omapbl_driver); |
172 | |
173 | MODULE_AUTHOR("Andrzej Zaborowski <balrog@zabor.org>" ); |
174 | MODULE_DESCRIPTION("OMAP LCD Backlight driver" ); |
175 | MODULE_LICENSE("GPL" ); |
176 | |