Svyatoslav Ryhel | 3e9488a | 2023-04-25 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 Ryhel | 3e9488a | 2023-04-25 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 | |
| 27 | struct lm3533_backlight_priv { |
| 28 | struct gpio_desc enable_gpio; |
| 29 | u32 def_bl_lvl; |
| 30 | }; |
| 31 | |
| 32 | static 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 | |
| 72 | static 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 | |
| 95 | static 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 | |
| 116 | static const struct backlight_ops lm3533_backlight_ops = { |
| 117 | .enable = lm3533_backlight_enable, |
| 118 | .set_brightness = lm3533_backlight_set_brightness, |
| 119 | }; |
| 120 | |
| 121 | static const struct udevice_id lm3533_backlight_ids[] = { |
| 122 | { .compatible = "ti,lm3533" }, |
| 123 | { } |
| 124 | }; |
| 125 | |
| 126 | U_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 | }; |