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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * TI LP8788 MFD - keyled driver4 *5 * Copyright 2012 Texas Instruments6 *7 * Author: Milo(Woogyom) Kim <milo.kim@ti.com>8 */9 10#include <linux/module.h>11#include <linux/slab.h>12#include <linux/err.h>13#include <linux/platform_device.h>14#include <linux/leds.h>15#include <linux/mutex.h>16#include <linux/mfd/lp8788.h>17#include <linux/mfd/lp8788-isink.h>18 19#define MAX_BRIGHTNESS LP8788_ISINK_MAX_PWM20#define DEFAULT_LED_NAME "keyboard-backlight"21 22struct lp8788_led {23 struct lp8788 *lp;24 struct mutex lock;25 struct led_classdev led_dev;26 enum lp8788_isink_number isink_num;27 int on;28};29 30struct lp8788_led_config {31 enum lp8788_isink_scale scale;32 enum lp8788_isink_number num;33 int iout;34};35 36static struct lp8788_led_config default_led_config = {37 .scale = LP8788_ISINK_SCALE_100mA,38 .num = LP8788_ISINK_3,39 .iout = 0,40};41 42static int lp8788_led_init_device(struct lp8788_led *led,43 struct lp8788_led_platform_data *pdata)44{45 struct lp8788_led_config *cfg = &default_led_config;46 u8 addr, mask, val;47 int ret;48 49 if (pdata) {50 cfg->scale = pdata->scale;51 cfg->num = pdata->num;52 cfg->iout = pdata->iout_code;53 }54 55 led->isink_num = cfg->num;56 57 /* scale configuration */58 addr = LP8788_ISINK_CTRL;59 mask = 1 << (cfg->num + LP8788_ISINK_SCALE_OFFSET);60 val = cfg->scale << (cfg->num + LP8788_ISINK_SCALE_OFFSET);61 ret = lp8788_update_bits(led->lp, addr, mask, val);62 if (ret)63 return ret;64 65 /* current configuration */66 addr = lp8788_iout_addr[cfg->num];67 mask = lp8788_iout_mask[cfg->num];68 val = cfg->iout;69 70 return lp8788_update_bits(led->lp, addr, mask, val);71}72 73static int lp8788_led_enable(struct lp8788_led *led,74 enum lp8788_isink_number num, int on)75{76 int ret;77 78 u8 mask = 1 << num;79 u8 val = on << num;80 81 ret = lp8788_update_bits(led->lp, LP8788_ISINK_CTRL, mask, val);82 if (ret == 0)83 led->on = on;84 85 return ret;86}87 88static int lp8788_brightness_set(struct led_classdev *led_cdev,89 enum led_brightness val)90{91 struct lp8788_led *led =92 container_of(led_cdev, struct lp8788_led, led_dev);93 94 enum lp8788_isink_number num = led->isink_num;95 int enable, ret;96 97 mutex_lock(&led->lock);98 99 switch (num) {100 case LP8788_ISINK_1:101 case LP8788_ISINK_2:102 case LP8788_ISINK_3:103 ret = lp8788_write_byte(led->lp, lp8788_pwm_addr[num], val);104 if (ret < 0)105 goto unlock;106 break;107 default:108 mutex_unlock(&led->lock);109 return -EINVAL;110 }111 112 enable = (val > 0) ? 1 : 0;113 if (enable != led->on)114 ret = lp8788_led_enable(led, num, enable);115unlock:116 mutex_unlock(&led->lock);117 return ret;118}119 120static int lp8788_led_probe(struct platform_device *pdev)121{122 struct lp8788 *lp = dev_get_drvdata(pdev->dev.parent);123 struct lp8788_led_platform_data *led_pdata;124 struct lp8788_led *led;125 struct device *dev = &pdev->dev;126 int ret;127 128 led = devm_kzalloc(dev, sizeof(struct lp8788_led), GFP_KERNEL);129 if (!led)130 return -ENOMEM;131 132 led->lp = lp;133 led->led_dev.max_brightness = MAX_BRIGHTNESS;134 led->led_dev.brightness_set_blocking = lp8788_brightness_set;135 136 led_pdata = lp->pdata ? lp->pdata->led_pdata : NULL;137 138 if (!led_pdata || !led_pdata->name)139 led->led_dev.name = DEFAULT_LED_NAME;140 else141 led->led_dev.name = led_pdata->name;142 143 mutex_init(&led->lock);144 145 ret = lp8788_led_init_device(led, led_pdata);146 if (ret) {147 dev_err(dev, "led init device err: %d\n", ret);148 return ret;149 }150 151 ret = devm_led_classdev_register(dev, &led->led_dev);152 if (ret) {153 dev_err(dev, "led register err: %d\n", ret);154 return ret;155 }156 157 return 0;158}159 160static struct platform_driver lp8788_led_driver = {161 .probe = lp8788_led_probe,162 .driver = {163 .name = LP8788_DEV_KEYLED,164 },165};166module_platform_driver(lp8788_led_driver);167 168MODULE_DESCRIPTION("Texas Instruments LP8788 Keyboard LED Driver");169MODULE_AUTHOR("Milo Kim");170MODULE_LICENSE("GPL");171MODULE_ALIAS("platform:lp8788-keyled");172