diff options
Diffstat (limited to 'drivers/power/reset/mt6323-poweroff.c')
| -rw-r--r-- | drivers/power/reset/mt6323-poweroff.c | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/drivers/power/reset/mt6323-poweroff.c b/drivers/power/reset/mt6323-poweroff.c new file mode 100644 index 000000000000..1caf43d9e46d --- /dev/null +++ b/drivers/power/reset/mt6323-poweroff.c @@ -0,0 +1,97 @@ +// 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, 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); + 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>"); +MODULE_LICENSE("GPL v2"); |