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1// SPDX-License-Identifier: GPL-2.02/*3 * Device driver for leds in MAX5970 and MAX5978 IC4 *5 * Copyright (c) 2022 9elements GmbH6 *7 * Author: Patrick Rudolph <patrick.rudolph@9elements.com>8 */9 10#include <linux/bits.h>11#include <linux/container_of.h>12#include <linux/device.h>13#include <linux/leds.h>14#include <linux/mfd/max5970.h>15#include <linux/mod_devicetable.h>16#include <linux/module.h>17#include <linux/platform_device.h>18#include <linux/property.h>19#include <linux/regmap.h>20 21#define ldev_to_maxled(c) container_of(c, struct max5970_led, cdev)22 23struct max5970_led {24 struct device *dev;25 struct regmap *regmap;26 struct led_classdev cdev;27 unsigned int index;28};29 30static int max5970_led_set_brightness(struct led_classdev *cdev,31 enum led_brightness brightness)32{33 struct max5970_led *ddata = ldev_to_maxled(cdev);34 int ret, val;35 36 /* Set/clear corresponding bit for given led index */37 val = !brightness ? BIT(ddata->index) : 0;38 39 ret = regmap_update_bits(ddata->regmap, MAX5970_REG_LED_FLASH, BIT(ddata->index), val);40 if (ret < 0)41 dev_err(cdev->dev, "failed to set brightness %d", ret);42 43 return ret;44}45 46static int max5970_led_probe(struct platform_device *pdev)47{48 struct fwnode_handle *led_node, *child;49 struct device *dev = &pdev->dev;50 struct regmap *regmap;51 struct max5970_led *ddata;52 int ret = -ENODEV;53 54 regmap = dev_get_regmap(dev->parent, NULL);55 if (!regmap)56 return -ENODEV;57 58 led_node = device_get_named_child_node(dev->parent, "leds");59 if (!led_node)60 return -ENODEV;61 62 fwnode_for_each_available_child_node(led_node, child) {63 u32 reg;64 65 if (fwnode_property_read_u32(child, "reg", ®))66 continue;67 68 if (reg >= MAX5970_NUM_LEDS) {69 dev_err_probe(dev, -EINVAL, "invalid LED (%u >= %d)\n", reg, MAX5970_NUM_LEDS);70 continue;71 }72 73 ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);74 if (!ddata) {75 fwnode_handle_put(child);76 return -ENOMEM;77 }78 79 ddata->index = reg;80 ddata->regmap = regmap;81 ddata->dev = dev;82 83 if (fwnode_property_read_string(child, "label", &ddata->cdev.name))84 ddata->cdev.name = fwnode_get_name(child);85 86 ddata->cdev.max_brightness = 1;87 ddata->cdev.brightness_set_blocking = max5970_led_set_brightness;88 ddata->cdev.default_trigger = "none";89 90 ret = devm_led_classdev_register(dev, &ddata->cdev);91 if (ret < 0) {92 fwnode_handle_put(child);93 return dev_err_probe(dev, ret, "Failed to initialize LED %u\n", reg);94 }95 }96 97 return ret;98}99 100static struct platform_driver max5970_led_driver = {101 .driver = {102 .name = "max5970-led",103 },104 .probe = max5970_led_probe,105};106module_platform_driver(max5970_led_driver);107 108MODULE_AUTHOR("Patrick Rudolph <patrick.rudolph@9elements.com>");109MODULE_AUTHOR("Naresh Solanki <Naresh.Solanki@9elements.com>");110MODULE_DESCRIPTION("MAX5970_hot-swap controller LED driver");111MODULE_LICENSE("GPL");112