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1// SPDX-License-Identifier: GPL-2.0+2 3/*4 * LCD Backlight driver for RAVE SP5 *6 * Copyright (C) 2018 Zodiac Inflight Innovations7 *8 */9 10#include <linux/backlight.h>11#include <linux/kernel.h>12#include <linux/module.h>13#include <linux/mfd/rave-sp.h>14#include <linux/platform_device.h>15 16#define RAVE_SP_BACKLIGHT_LCD_EN BIT(7)17 18static int rave_sp_backlight_update_status(struct backlight_device *bd)19{20 const struct backlight_properties *p = &bd->props;21 const u8 intensity =22 (p->power == BACKLIGHT_POWER_ON) ? p->brightness : 0;23 struct rave_sp *sp = dev_get_drvdata(&bd->dev);24 u8 cmd[] = {25 [0] = RAVE_SP_CMD_SET_BACKLIGHT,26 [1] = 0,27 [2] = intensity ? RAVE_SP_BACKLIGHT_LCD_EN | intensity : 0,28 [3] = 0,29 [4] = 0,30 };31 32 return rave_sp_exec(sp, cmd, sizeof(cmd), NULL, 0);33}34 35static const struct backlight_ops rave_sp_backlight_ops = {36 .options = BL_CORE_SUSPENDRESUME,37 .update_status = rave_sp_backlight_update_status,38};39 40static struct backlight_properties rave_sp_backlight_props = {41 .type = BACKLIGHT_PLATFORM,42 .max_brightness = 100,43 .brightness = 50,44};45 46static int rave_sp_backlight_probe(struct platform_device *pdev)47{48 struct device *dev = &pdev->dev;49 struct backlight_device *bd;50 51 bd = devm_backlight_device_register(dev, pdev->name, dev,52 dev_get_drvdata(dev->parent),53 &rave_sp_backlight_ops,54 &rave_sp_backlight_props);55 if (IS_ERR(bd))56 return PTR_ERR(bd);57 58 /*59 * If there is a phandle pointing to the device node we can60 * assume that another device will manage the status changes.61 * If not we make sure the backlight is in a consistent state.62 */63 if (!dev->of_node->phandle)64 backlight_update_status(bd);65 66 return 0;67}68 69static const struct of_device_id rave_sp_backlight_of_match[] = {70 { .compatible = "zii,rave-sp-backlight" },71 {}72};73 74static struct platform_driver rave_sp_backlight_driver = {75 .probe = rave_sp_backlight_probe,76 .driver = {77 .name = KBUILD_MODNAME,78 .of_match_table = rave_sp_backlight_of_match,79 },80};81module_platform_driver(rave_sp_backlight_driver);82 83MODULE_DEVICE_TABLE(of, rave_sp_backlight_of_match);84MODULE_LICENSE("GPL");85MODULE_AUTHOR("Andrey Vostrikov <andrey.vostrikov@cogentembedded.com>");86MODULE_AUTHOR("Nikita Yushchenko <nikita.yoush@cogentembedded.com>");87MODULE_AUTHOR("Andrey Smirnov <andrew.smirnov@gmail.com>");88MODULE_DESCRIPTION("RAVE SP Backlight driver");89