// SPDX-License-Identifier: GPL-2.0+ /* * LCD Backlight driver for RAVE SP * * Copyright (C) 2018 Zodiac Inflight Innovations * */ #include <linux/backlight.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/mfd/rave-sp.h> #include <linux/platform_device.h> #define RAVE_SP_BACKLIGHT_LCD_EN BIT(7) static int rave_sp_backlight_update_status(struct backlight_device *bd) { const struct backlight_properties *p = &bd->props; const u8 intensity = (p->power == FB_BLANK_UNBLANK) ? p->brightness : 0; struct rave_sp *sp = dev_get_drvdata(&bd->dev); u8 cmd[] = { [0] = RAVE_SP_CMD_SET_BACKLIGHT, [1] = 0, [2] = intensity ? RAVE_SP_BACKLIGHT_LCD_EN | intensity : 0, [3] = 0, [4] = 0, }; return rave_sp_exec(sp, cmd, sizeof(cmd), NULL, 0); } static const struct backlight_ops rave_sp_backlight_ops = { .options = BL_CORE_SUSPENDRESUME, .update_status = rave_sp_backlight_update_status, }; static struct backlight_properties rave_sp_backlight_props = { .type = BACKLIGHT_PLATFORM, .max_brightness = 100, .brightness = 50, }; static int rave_sp_backlight_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct backlight_device *bd; bd = devm_backlight_device_register(dev, pdev->name, dev, dev_get_drvdata(dev->parent), &rave_sp_backlight_ops, &rave_sp_backlight_props); if (IS_ERR(bd)) return PTR_ERR(bd); /* * If there is a phandle pointing to the device node we can * assume that another device will manage the status changes. * If not we make sure the backlight is in a consistent state. */ if (!dev->of_node->phandle) backlight_update_status(bd); return 0; } static const struct of_device_id rave_sp_backlight_of_match[] = { { .compatible = "zii,rave-sp-backlight" }, {} }; static struct platform_driver rave_sp_backlight_driver = { .probe = rave_sp_backlight_probe, .driver = { .name = KBUILD_MODNAME, .of_match_table = rave_sp_backlight_of_match, }, }; module_platform_driver(rave_sp_backlight_driver); MODULE_DEVICE_TABLE(of, rave_sp_backlight_of_match); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Andrey Vostrikov <andrey.vostrikov@cogentembedded.com>"); MODULE_AUTHOR("Nikita Yushchenko <nikita.yoush@cogentembedded.com>"); MODULE_AUTHOR("Andrey Smirnov <andrew.smirnov@gmail.com>"); MODULE_DESCRIPTION("RAVE SP Backlight driver");