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 fwnode_handle *child; 66 struct max77650_led *leds, *led; 67 struct device *dev; 68 struct regmap *map; 69 int rv, num_leds; 70 u32 reg; 71 72 dev = &pdev->dev; 73 74 leds = devm_kcalloc(dev, sizeof(*leds), 75 MAX77650_LED_NUM_LEDS, GFP_KERNEL); 76 if (!leds) 77 return -ENOMEM; 78 79 map = dev_get_regmap(dev->parent, NULL); 80 if (!map) 81 return -ENODEV; 82 83 num_leds = device_get_child_node_count(dev); 84 if (!num_leds || num_leds > MAX77650_LED_NUM_LEDS) 85 return -ENODEV; 86 87 device_for_each_child_node(dev, child) { 88 struct led_init_data init_data = {}; 89 90 rv = fwnode_property_read_u32(child, "reg", ®); 91 if (rv || reg >= MAX77650_LED_NUM_LEDS) { 92 rv = -EINVAL; 93 goto err_node_put; 94 } 95 96 led = &leds[reg]; 97 led->map = map; 98 led->regA = MAX77650_LED_A_BASE + reg; 99 led->regB = MAX77650_LED_B_BASE + reg; 100 led->cdev.brightness_set_blocking = max77650_led_brightness_set; 101 led->cdev.max_brightness = MAX77650_LED_MAX_BRIGHTNESS; 102 103 init_data.fwnode = child; 104 init_data.devicename = "max77650"; 105 /* for backwards compatibility if `label` is not present */ 106 init_data.default_label = ":"; 107 108 rv = devm_led_classdev_register_ext(dev, &led->cdev, 109 &init_data); 110 if (rv) 111 goto err_node_put; 112 113 rv = regmap_write(map, led->regA, MAX77650_LED_A_DEFAULT); 114 if (rv) 115 goto err_node_put; 116 117 rv = regmap_write(map, led->regB, MAX77650_LED_B_DEFAULT); 118 if (rv) 119 goto err_node_put; 120 } 121 122 return regmap_write(map, 123 MAX77650_REG_CNFG_LED_TOP, 124 MAX77650_LED_TOP_DEFAULT); 125 err_node_put: 126 fwnode_handle_put(child); 127 return rv; 128 } 129 130 static const struct of_device_id max77650_led_of_match[] = { 131 { .compatible = "maxim,max77650-led" }, 132 { } 133 }; 134 MODULE_DEVICE_TABLE(of, max77650_led_of_match); 135 136 static struct platform_driver max77650_led_driver = { 137 .driver = { 138 .name = "max77650-led", 139 .of_match_table = max77650_led_of_match, 140 }, 141 .probe = max77650_led_probe, 142 }; 143 module_platform_driver(max77650_led_driver); 144 145 MODULE_DESCRIPTION("MAXIM 77650/77651 LED driver"); 146 MODULE_AUTHOR("Bartosz Golaszewski <bgolaszewski@baylibre.com>"); 147 MODULE_LICENSE("GPL v2"); 148 MODULE_ALIAS("platform:max77650-led"); 149