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gerrit.cesnet.cz / github / trini / u-boot / e3b2ae6dc6816881a3777a7d033d842bbe3c3a46 / . / drivers / video / lm3533_backlight.c
blob: 6b51fa0628e4c152539968626c8f8f4ce7e24308 [file] [log] [blame]
Svyatoslav Ryhel06020832023-04-25 10:51:42 +0300[diff] [blame]1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Copyright (c) 2022 Svyatoslav Ryhel <clamor95@gmail.com>
4 */
5
6#define LOG_CATEGORY UCLASS_PANEL_BACKLIGHT
7
8#include <backlight.h>
Svyatoslav Ryhel06020832023-04-25 10:51:42 +0300[diff] [blame]9#include <dm.h>
10#include <i2c.h>
11#include <log.h>
12#include <linux/delay.h>
13#include <linux/err.h>
14#include <asm/gpio.h>
15
16#define LM3533_BL_MIN_BRIGHTNESS 0x02
17#define LM3533_BL_MAX_BRIGHTNESS 0xFF
18
19#define LM3533_SINK_OUTPUT_CONFIG_1 0x10
20#define LM3533_CONTROL_BANK_A_PWM 0x14
21#define LM3533_CONTROL_BANK_AB_BRIGHTNESS 0x1A
22#define LM3533_CONTROL_BANK_A_FULLSCALE_CURRENT 0x1F
23#define LM3533_CONTROL_BANK_ENABLE 0x27
24#define LM3533_OVP_FREQUENCY_PWM_POLARITY 0x2C
25#define LM3533_BRIGHTNESS_REGISTER_A 0x40
26
27struct lm3533_backlight_priv {
28 struct gpio_desc enable_gpio;
29 u32 def_bl_lvl;
30};
31
32static int lm3533_backlight_enable(struct udevice *dev)
33{
34 struct lm3533_backlight_priv *priv = dev_get_priv(dev);
35 int ret;
36
37 dm_gpio_set_value(&priv->enable_gpio, 1);
38 mdelay(5);
39
40 /* HVLED 1 & 2 are controlled by Bank A */
41 ret = dm_i2c_reg_write(dev, LM3533_SINK_OUTPUT_CONFIG_1, 0x00);
42 if (ret)
43 return ret;
44
45 /* PWM input is disabled for CABC */
46 ret = dm_i2c_reg_write(dev, LM3533_CONTROL_BANK_A_PWM, 0x00);
47 if (ret)
48 return ret;
49
50 /* Linear & Control Bank A is configured for register Current control */
51 ret = dm_i2c_reg_write(dev, LM3533_CONTROL_BANK_AB_BRIGHTNESS, 0x02);
52 if (ret)
53 return ret;
54
55 /* Full-Scale Current (20.2mA) */
56 ret = dm_i2c_reg_write(dev, LM3533_CONTROL_BANK_A_FULLSCALE_CURRENT, 0x13);
57 if (ret)
58 return ret;
59
60 /* Control Bank A is enable */
61 ret = dm_i2c_reg_write(dev, LM3533_CONTROL_BANK_ENABLE, 0x01);
62 if (ret)
63 return ret;
64
65 ret = dm_i2c_reg_write(dev, LM3533_OVP_FREQUENCY_PWM_POLARITY, 0x0A);
66 if (ret)
67 return ret;
68
69 return 0;
70}
71
72static int lm3533_backlight_set_brightness(struct udevice *dev, int percent)
73{
74 struct lm3533_backlight_priv *priv = dev_get_priv(dev);
75 int ret;
76
77 if (percent == BACKLIGHT_DEFAULT)
78 percent = priv->def_bl_lvl;
79
80 if (percent < LM3533_BL_MIN_BRIGHTNESS)
81 percent = LM3533_BL_MIN_BRIGHTNESS;
82
83 if (percent > LM3533_BL_MAX_BRIGHTNESS)
84 percent = LM3533_BL_MAX_BRIGHTNESS;
85
86 /* Set brightness level */
87 ret = dm_i2c_reg_write(dev, LM3533_BRIGHTNESS_REGISTER_A,
88 percent);
89 if (ret)
90 return ret;
91
92 return 0;
93}
94
95static int lm3533_backlight_probe(struct udevice *dev)
96{
97 struct lm3533_backlight_priv *priv = dev_get_priv(dev);
98 int ret;
99
100 if (device_get_uclass_id(dev->parent) != UCLASS_I2C)
101 return -EPROTONOSUPPORT;
102
103 ret = gpio_request_by_name(dev, "enable-gpios", 0,
104 &priv->enable_gpio, GPIOD_IS_OUT);
105 if (ret) {
106 log_err("Could not decode enable-gpios (%d)\n", ret);
107 return ret;
108 }
109
110 priv->def_bl_lvl = dev_read_u32_default(dev, "default-brightness-level",
111 LM3533_BL_MAX_BRIGHTNESS);
112
113 return 0;
114}
115
116static const struct backlight_ops lm3533_backlight_ops = {
117 .enable = lm3533_backlight_enable,
118 .set_brightness = lm3533_backlight_set_brightness,
119};
120
121static const struct udevice_id lm3533_backlight_ids[] = {
122 { .compatible = "ti,lm3533" },
123 { }
124};
125
126U_BOOT_DRIVER(lm3533_backlight) = {
127 .name = "lm3533_backlight",
128 .id = UCLASS_PANEL_BACKLIGHT,
129 .of_match = lm3533_backlight_ids,
130 .probe = lm3533_backlight_probe,
131 .ops = &lm3533_backlight_ops,
132 .priv_auto = sizeof(struct lm3533_backlight_priv),
133};