1 // SPDX-License-Identifier: GPL-2.0 2 // 3 // Copyright (C) 2018 BayLibre SAS 4 // Author: Bartosz Golaszewski <bgolaszewski@baylibre.com> 5 // 6 // LED driver for MAXIM 77650/77651 charger/power-supply. 7 8 #include <linux/i2c.h> 9 #include <linux/leds.h> 10 #include <linux/mfd/max77650.h> 11 #include <linux/module.h> 12 #include <linux/platform_device.h> 13 #include <linux/regmap.h> 14 15 #define MAX77650_LED_NUM_LEDS 3 16 17 #define MAX77650_LED_A_BASE 0x40 18 #define MAX77650_LED_B_BASE 0x43 19 20 #define MAX77650_LED_BR_MASK GENMASK(4, 0) 21 #define MAX77650_LED_EN_MASK GENMASK(7, 6) 22 23 #define MAX77650_LED_MAX_BRIGHTNESS MAX77650_LED_BR_MASK 24 25 /* Enable EN_LED_MSTR. */ 26 #define MAX77650_LED_TOP_DEFAULT BIT(0) 27 28 #define MAX77650_LED_ENABLE GENMASK(7, 6) 29 #define MAX77650_LED_DISABLE 0x00 30 31 #define MAX77650_LED_A_DEFAULT MAX77650_LED_DISABLE 32 /* 100% on duty */ 33 #define MAX77650_LED_B_DEFAULT GENMASK(3, 0) 34 35 struct max77650_led { 36 struct led_classdev cdev; 37 struct regmap *map; 38 unsigned int regA; 39 unsigned int regB; 40 }; 41 42 static struct max77650_led *max77650_to_led(struct led_classdev *cdev) 43 { 44 return container_of(cdev, struct max77650_led, cdev); 45 } 46 47 static int max77650_led_brightness_set(struct led_classdev *cdev, 48 enum led_brightness brightness) 49 { 50 struct max77650_led *led = max77650_to_led(cdev); 51 int val, mask; 52 53 mask = MAX77650_LED_BR_MASK | MAX77650_LED_EN_MASK; 54 55 if (brightness == LED_OFF) 56 val = MAX77650_LED_DISABLE; 57 else 58 val = MAX77650_LED_ENABLE | brightness; 59 60 return regmap_update_bits(led->map, led->regA, mask, val); 61 } 62 63 static int max77650_led_probe(struct platform_device *pdev) 64 { 65 struct max77650_led *leds, *led; 66 struct device *dev; 67 struct regmap *map; 68 int rv, num_leds; 69 u32 reg; 70 71 dev = &pdev->dev; 72 73 leds = devm_kcalloc(dev, sizeof(*leds), 74 MAX77650_LED_NUM_LEDS, GFP_KERNEL); 75 if (!leds) 76 return -ENOMEM; 77 78 map = dev_get_regmap(dev->parent, NULL); 79 if (!map) 80 return -ENODEV; 81 82 num_leds = device_get_child_node_count(dev); 83 if (!num_leds || num_leds > MAX77650_LED_NUM_LEDS) 84 return -ENODEV; 85 86 device_for_each_child_node_scoped(dev, child) { 87 struct led_init_data init_data = {}; 88 89 rv = fwnode_property_read_u32(child, "reg", ®); 90 if (rv || reg >= MAX77650_LED_NUM_LEDS) 91 return -EINVAL; 92 93 led = &leds[reg]; 94 led->map = map; 95 led->regA = MAX77650_LED_A_BASE + reg; 96 led->regB = MAX77650_LED_B_BASE + reg; 97 led->cdev.brightness_set_blocking = max77650_led_brightness_set; 98 led->cdev.max_brightness = MAX77650_LED_MAX_BRIGHTNESS; 99 100 init_data.fwnode = child; 101 init_data.devicename = "max77650"; 102 /* for backwards compatibility if `label` is not present */ 103 init_data.default_label = ":"; 104 105 rv = devm_led_classdev_register_ext(dev, &led->cdev, 106 &init_data); 107 if (rv) 108 return rv; 109 110 rv = regmap_write(map, led->regA, MAX77650_LED_A_DEFAULT); 111 if (rv) 112 return rv; 113 114 rv = regmap_write(map, led->regB, MAX77650_LED_B_DEFAULT); 115 if (rv) 116 return rv; 117 } 118 119 return regmap_write(map, 120 MAX77650_REG_CNFG_LED_TOP, 121 MAX77650_LED_TOP_DEFAULT); 122 } 123 124 static const struct of_device_id max77650_led_of_match[] = { 125 { .compatible = "maxim,max77650-led" }, 126 { } 127 }; 128 MODULE_DEVICE_TABLE(of, max77650_led_of_match); 129 130 static struct platform_driver max77650_led_driver = { 131 .driver = { 132 .name = "max77650-led", 133 .of_match_table = max77650_led_of_match, 134 }, 135 .probe = max77650_led_probe, 136 }; 137 module_platform_driver(max77650_led_driver); 138 139 MODULE_DESCRIPTION("MAXIM 77650/77651 LED driver"); 140 MODULE_AUTHOR("Bartosz Golaszewski <bgolaszewski@baylibre.com>"); 141 MODULE_LICENSE("GPL v2"); 142 MODULE_ALIAS("platform:max77650-led"); 143