// SPDX-License-Identifier: GPL-2.0 /* * Power off through MediaTek PMIC * * Copyright (C) 2018 MediaTek Inc. * * Author: Sean Wang <sean.wang@mediatek.com> * */ #include <linux/err.h> #include <linux/module.h> #include <linux/of.h> #include <linux/platform_device.h> #include <linux/mfd/mt6397/core.h> #include <linux/mfd/mt6397/rtc.h> struct mt6323_pwrc { struct device *dev; struct regmap *regmap; u32 base; }; static struct mt6323_pwrc *mt_pwrc; static void mt6323_do_pwroff(void) { struct mt6323_pwrc *pwrc = mt_pwrc; unsigned int val; int ret; regmap_write(pwrc->regmap, pwrc->base + RTC_BBPU, RTC_BBPU_KEY); regmap_write(pwrc->regmap, pwrc->base + RTC_WRTGR_MT6323, 1); ret = regmap_read_poll_timeout(pwrc->regmap, pwrc->base + RTC_BBPU, val, !(val & RTC_BBPU_CBUSY), MTK_RTC_POLL_DELAY_US, MTK_RTC_POLL_TIMEOUT); if (ret) dev_err(pwrc->dev, "failed to write BBPU: %d\n", ret); /* Wait some time until system down, otherwise, notice with a warn */ mdelay(1000); WARN_ONCE(1, "Unable to power off system\n"); } static int mt6323_pwrc_probe(struct platform_device *pdev) { struct mt6397_chip *mt6397_chip = dev_get_drvdata(pdev->dev.parent); struct mt6323_pwrc *pwrc; struct resource *res; pwrc = devm_kzalloc(&pdev->dev, sizeof(*pwrc), GFP_KERNEL); if (!pwrc) return -ENOMEM; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) return -EINVAL; pwrc->base = res->start; pwrc->regmap = mt6397_chip->regmap; pwrc->dev = &pdev->dev; mt_pwrc = pwrc; pm_power_off = &mt6323_do_pwroff; return 0; } static int mt6323_pwrc_remove(struct platform_device *pdev) { if (pm_power_off == &mt6323_do_pwroff) pm_power_off = NULL; return 0; } static const struct of_device_id mt6323_pwrc_dt_match[] = { { .compatible = "mediatek,mt6323-pwrc" }, {}, }; MODULE_DEVICE_TABLE(of, mt6323_pwrc_dt_match); static struct platform_driver mt6323_pwrc_driver = { .probe = mt6323_pwrc_probe, .remove = mt6323_pwrc_remove, .driver = { .name = "mt6323-pwrc", .of_match_table = mt6323_pwrc_dt_match, }, }; module_platform_driver(mt6323_pwrc_driver); MODULE_DESCRIPTION("Poweroff driver for MT6323 PMIC"); MODULE_AUTHOR("Sean Wang <sean.wang@mediatek.com>");