1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Backlight Driver for Dialog DA9052 PMICs 4 * 5 * Copyright(c) 2012 Dialog Semiconductor Ltd. 6 * 7 * Author: David Dajun Chen <dchen@diasemi.com> 8 */ 9 10 #include <linux/backlight.h> 11 #include <linux/delay.h> 12 #include <linux/module.h> 13 #include <linux/platform_device.h> 14 15 #include <linux/mfd/da9052/da9052.h> 16 #include <linux/mfd/da9052/reg.h> 17 18 #define DA9052_MAX_BRIGHTNESS 0xFF 19 20 enum { 21 DA9052_WLEDS_OFF, 22 DA9052_WLEDS_ON, 23 }; 24 25 enum { 26 DA9052_TYPE_WLED1, 27 DA9052_TYPE_WLED2, 28 DA9052_TYPE_WLED3, 29 }; 30 31 static const unsigned char wled_bank[] = { 32 DA9052_LED1_CONF_REG, 33 DA9052_LED2_CONF_REG, 34 DA9052_LED3_CONF_REG, 35 }; 36 37 struct da9052_bl { 38 struct da9052 *da9052; 39 uint brightness; 40 uint state; 41 uint led_reg; 42 }; 43 44 static int da9052_adjust_wled_brightness(struct da9052_bl *wleds) 45 { 46 unsigned char boost_en; 47 unsigned char i_sink; 48 int ret; 49 50 boost_en = 0x3F; 51 i_sink = 0xFF; 52 if (wleds->state == DA9052_WLEDS_OFF) { 53 boost_en = 0x00; 54 i_sink = 0x00; 55 } 56 57 ret = da9052_reg_write(wleds->da9052, DA9052_BOOST_REG, boost_en); 58 if (ret < 0) 59 return ret; 60 61 ret = da9052_reg_write(wleds->da9052, DA9052_LED_CONT_REG, i_sink); 62 if (ret < 0) 63 return ret; 64 65 ret = da9052_reg_write(wleds->da9052, wled_bank[wleds->led_reg], 0x0); 66 if (ret < 0) 67 return ret; 68 69 usleep_range(10000, 11000); 70 71 if (wleds->brightness) { 72 ret = da9052_reg_write(wleds->da9052, wled_bank[wleds->led_reg], 73 wleds->brightness); 74 if (ret < 0) 75 return ret; 76 } 77 78 return 0; 79 } 80 81 static int da9052_backlight_update_status(struct backlight_device *bl) 82 { 83 int brightness = bl->props.brightness; 84 struct da9052_bl *wleds = bl_get_data(bl); 85 86 wleds->brightness = brightness; 87 wleds->state = DA9052_WLEDS_ON; 88 89 return da9052_adjust_wled_brightness(wleds); 90 } 91 92 static int da9052_backlight_get_brightness(struct backlight_device *bl) 93 { 94 struct da9052_bl *wleds = bl_get_data(bl); 95 96 return wleds->brightness; 97 } 98 99 static const struct backlight_ops da9052_backlight_ops = { 100 .update_status = da9052_backlight_update_status, 101 .get_brightness = da9052_backlight_get_brightness, 102 }; 103 104 static int da9052_backlight_probe(struct platform_device *pdev) 105 { 106 struct backlight_device *bl; 107 struct backlight_properties props; 108 struct da9052_bl *wleds; 109 110 wleds = devm_kzalloc(&pdev->dev, sizeof(struct da9052_bl), GFP_KERNEL); 111 if (!wleds) 112 return -ENOMEM; 113 114 wleds->da9052 = dev_get_drvdata(pdev->dev.parent); 115 wleds->brightness = 0; 116 wleds->led_reg = platform_get_device_id(pdev)->driver_data; 117 wleds->state = DA9052_WLEDS_OFF; 118 119 memset(&props, 0, sizeof(struct backlight_properties)); 120 props.type = BACKLIGHT_RAW; 121 props.max_brightness = DA9052_MAX_BRIGHTNESS; 122 123 bl = devm_backlight_device_register(&pdev->dev, pdev->name, 124 wleds->da9052->dev, wleds, 125 &da9052_backlight_ops, &props); 126 if (IS_ERR(bl)) { 127 dev_err(&pdev->dev, "Failed to register backlight\n"); 128 return PTR_ERR(bl); 129 } 130 131 bl->props.max_brightness = DA9052_MAX_BRIGHTNESS; 132 bl->props.brightness = 0; 133 platform_set_drvdata(pdev, bl); 134 135 return da9052_adjust_wled_brightness(wleds); 136 } 137 138 static void da9052_backlight_remove(struct platform_device *pdev) 139 { 140 struct backlight_device *bl = platform_get_drvdata(pdev); 141 struct da9052_bl *wleds = bl_get_data(bl); 142 143 wleds->brightness = 0; 144 wleds->state = DA9052_WLEDS_OFF; 145 da9052_adjust_wled_brightness(wleds); 146 } 147 148 static const struct platform_device_id da9052_wled_ids[] = { 149 { 150 .name = "da9052-wled1", 151 .driver_data = DA9052_TYPE_WLED1, 152 }, 153 { 154 .name = "da9052-wled2", 155 .driver_data = DA9052_TYPE_WLED2, 156 }, 157 { 158 .name = "da9052-wled3", 159 .driver_data = DA9052_TYPE_WLED3, 160 }, 161 { }, 162 }; 163 MODULE_DEVICE_TABLE(platform, da9052_wled_ids); 164 165 static struct platform_driver da9052_wled_driver = { 166 .probe = da9052_backlight_probe, 167 .remove = da9052_backlight_remove, 168 .id_table = da9052_wled_ids, 169 .driver = { 170 .name = "da9052-wled", 171 }, 172 }; 173 174 module_platform_driver(da9052_wled_driver); 175 176 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>"); 177 MODULE_DESCRIPTION("Backlight driver for DA9052 PMIC"); 178 MODULE_LICENSE("GPL"); 179