// SPDX-License-Identifier: GPL-2.0 /* * The RTC driver for Sunplus	SP7021 * * Copyright (C) 2019 Sunplus Technology Inc., All rights reseerved. */ #include <linux/bitfield.h>#include <linux/clk.h>#include <linux/err.h>#include <linux/io.h>#include <linux/ktime.h>#include <linux/module.h>#include <linux/of.h>#include <linux/platform_device.h>#include <linux/reset.h>#include <linux/rtc.h> #define RTC_REG_NAME			"rtc" #define RTC_CTRL			0x40#define TIMER_FREEZE_MASK_BIT		BIT(5 + 16)#define TIMER_FREEZE			BIT(5)#define DIS_SYS_RST_RTC_MASK_BIT	BIT(4 + 16)#define DIS_SYS_RST_RTC			BIT(4)#define RTC32K_MODE_RESET_MASK_BIT	BIT(3 + 16)#define RTC32K_MODE_RESET		BIT(3)#define ALARM_EN_OVERDUE_MASK_BIT	BIT(2 + 16)#define ALARM_EN_OVERDUE		BIT(2)#define ALARM_EN_PMC_MASK_BIT		BIT(1 + 16)#define ALARM_EN_PMC			BIT(1)#define ALARM_EN_MASK_BIT		BIT(0 + 16)#define ALARM_EN			BIT(0)#define RTC_TIMER_OUT			0x44#define RTC_DIVIDER			0x48#define RTC_TIMER_SET			0x4c#define RTC_ALARM_SET			0x50#define RTC_USER_DATA			0x54#define RTC_RESET_RECORD		0x58#define RTC_BATT_CHARGE_CTRL		0x5c#define BAT_CHARGE_RSEL_MASK_BIT	GENMASK(3 + 16, 2 + 16)#define BAT_CHARGE_RSEL_MASK		GENMASK(3, 2)#define BAT_CHARGE_RSEL_2K_OHM		FIELD_PREP(BAT_CHARGE_RSEL_MASK, 0)#define BAT_CHARGE_RSEL_250_OHM		FIELD_PREP(BAT_CHARGE_RSEL_MASK, 1)#define BAT_CHARGE_RSEL_50_OHM		FIELD_PREP(BAT_CHARGE_RSEL_MASK, 2)#define BAT_CHARGE_RSEL_0_OHM		FIELD_PREP(BAT_CHARGE_RSEL_MASK, 3)#define BAT_CHARGE_DSEL_MASK_BIT	BIT(1 + 16)#define BAT_CHARGE_DSEL_MASK		GENMASK(1, 1)#define BAT_CHARGE_DSEL_ON		FIELD_PREP(BAT_CHARGE_DSEL_MASK, 0)#define BAT_CHARGE_DSEL_OFF		FIELD_PREP(BAT_CHARGE_DSEL_MASK, 1)#define BAT_CHARGE_EN_MASK_BIT		BIT(0 + 16)#define BAT_CHARGE_EN			BIT(0)#define RTC_TRIM_CTRL			0x60 struct sunplus_rtc {	struct rtc_device *rtc;	struct resource *res;	struct clk *rtcclk;	struct reset_control *rstc;	void __iomem *reg_base;	int irq;}; static void sp_get_seconds(struct device *dev, unsigned long *secs){	struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev); 	*secs = (unsigned long)readl(sp_rtc->reg_base + RTC_TIMER_OUT);} static void sp_set_seconds(struct device *dev, unsigned long secs){	struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev); 	writel((u32)secs, sp_rtc->reg_base + RTC_TIMER_SET);} static int sp_rtc_read_time(struct device *dev, struct rtc_time *tm){	unsigned long secs; 	sp_get_seconds(dev, &secs);	rtc_time64_to_tm(secs, tm); 	return 0;} static int sp_rtc_set_time(struct device *dev, struct rtc_time *tm){	unsigned long secs; 	secs = rtc_tm_to_time64(tm);	dev_dbg(dev, "%s, secs = %lu\n", __func__, secs);	sp_set_seconds(dev, secs); 	return 0;} static int sp_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm){	struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev);	unsigned long alarm_time; 	alarm_time = rtc_tm_to_time64(&alrm->time);	dev_dbg(dev, "%s, alarm_time: %u\n", __func__, (u32)(alarm_time));	writel((u32)alarm_time, sp_rtc->reg_base + RTC_ALARM_SET); 	return 0;} static int sp_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm){	struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev);	unsigned int alarm_time; 	alarm_time = readl(sp_rtc->reg_base + RTC_ALARM_SET);	dev_dbg(dev, "%s, alarm_time: %u\n", __func__, alarm_time); 	if (alarm_time == 0)		alrm->enabled = 0;	else		alrm->enabled = 1; 	rtc_time64_to_tm((unsigned long)(alarm_time), &alrm->time); 	return 0;} static int sp_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled){	struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev); 	if (enabled)		writel((TIMER_FREEZE_MASK_BIT | DIS_SYS_RST_RTC_MASK_BIT |			RTC32K_MODE_RESET_MASK_BIT | ALARM_EN_OVERDUE_MASK_BIT |			ALARM_EN_PMC_MASK_BIT | ALARM_EN_MASK_BIT) |			(DIS_SYS_RST_RTC | ALARM_EN_OVERDUE | ALARM_EN_PMC | ALARM_EN),			sp_rtc->reg_base + RTC_CTRL);	else		writel((ALARM_EN_OVERDUE_MASK_BIT | ALARM_EN_PMC_MASK_BIT | ALARM_EN_MASK_BIT) |			0x0, sp_rtc->reg_base + RTC_CTRL); 	return 0;} static const struct rtc_class_ops sp_rtc_ops = {	.read_time =		sp_rtc_read_time,	.set_time =		sp_rtc_set_time,	.set_alarm =		sp_rtc_set_alarm,	.read_alarm =		sp_rtc_read_alarm,	.alarm_irq_enable =	sp_rtc_alarm_irq_enable,}; static irqreturn_t sp_rtc_irq_handler(int irq, void *dev_id){	struct platform_device *plat_dev = dev_id;	struct sunplus_rtc *sp_rtc = dev_get_drvdata(&plat_dev->dev); 	rtc_update_irq(sp_rtc->rtc, 1, RTC_IRQF | RTC_AF);	dev_dbg(&plat_dev->dev, "[RTC] ALARM INT\n"); 	return IRQ_HANDLED;} /* * ------------------------------------------------------------------------------------- * bat_charge_rsel   bat_charge_dsel   bat_charge_en     Remarks *         x              x                 0            Disable *         0              0                 1            0.86mA (2K Ohm with diode) *         1              0                 1            1.81mA (250 Ohm with diode) *         2              0                 1            2.07mA (50 Ohm with diode) *         3              0                 1            16.0mA (0 Ohm with diode) *         0              1                 1            1.36mA (2K Ohm without diode) *         1              1                 1            3.99mA (250 Ohm without diode) *         2              1                 1            4.41mA (50 Ohm without diode) *         3              1                 1            16.0mA (0 Ohm without diode) * ------------------------------------------------------------------------------------- */static void sp_rtc_set_trickle_charger(struct device dev){	struct sunplus_rtc *sp_rtc = dev_get_drvdata(&dev);	u32 ohms, rsel;	u32 chargeable; 	if (of_property_read_u32(dev.of_node, "trickle-resistor-ohms", &ohms) ||	    of_property_read_u32(dev.of_node, "aux-voltage-chargeable", &chargeable)) {		dev_warn(&dev, "battery charger disabled\n");		return;	} 	switch (ohms) {	case 2000:		rsel = BAT_CHARGE_RSEL_2K_OHM;		break;	case 250:		rsel = BAT_CHARGE_RSEL_250_OHM;		break;	case 50:		rsel = BAT_CHARGE_RSEL_50_OHM;		break;	case 0:		rsel = BAT_CHARGE_RSEL_0_OHM;		break;	default:		dev_err(&dev, "invalid charger resistor value (%d)\n", ohms);		return;	} 	writel(BAT_CHARGE_RSEL_MASK_BIT | rsel, sp_rtc->reg_base + RTC_BATT_CHARGE_CTRL); 	switch (chargeable) {	case 0:		writel(BAT_CHARGE_DSEL_MASK_BIT | BAT_CHARGE_DSEL_OFF,		       sp_rtc->reg_base + RTC_BATT_CHARGE_CTRL);		break;	case 1:		writel(BAT_CHARGE_DSEL_MASK_BIT | BAT_CHARGE_DSEL_ON,		       sp_rtc->reg_base + RTC_BATT_CHARGE_CTRL);		break;	default:		dev_err(&dev, "invalid aux-voltage-chargeable value (%d)\n", chargeable);		return;	} 	writel(BAT_CHARGE_EN_MASK_BIT | BAT_CHARGE_EN, sp_rtc->reg_base + RTC_BATT_CHARGE_CTRL);} static int sp_rtc_probe(struct platform_device *plat_dev){	struct sunplus_rtc *sp_rtc;	int ret; 	sp_rtc = devm_kzalloc(&plat_dev->dev, sizeof(*sp_rtc), GFP_KERNEL);	if (!sp_rtc)		return -ENOMEM; 	sp_rtc->reg_base = devm_platform_ioremap_resource_byname(plat_dev, RTC_REG_NAME);	if (IS_ERR(sp_rtc->reg_base))		return dev_err_probe(&plat_dev->dev, PTR_ERR(sp_rtc->reg_base),					    "%s devm_ioremap_resource fail\n", RTC_REG_NAME);	dev_dbg(&plat_dev->dev, "res = %pR, reg_base = %p\n",		sp_rtc->res, sp_rtc->reg_base); 	sp_rtc->irq = platform_get_irq(plat_dev, 0);	if (sp_rtc->irq < 0)		return sp_rtc->irq; 	ret = devm_request_irq(&plat_dev->dev, sp_rtc->irq, sp_rtc_irq_handler,			       IRQF_TRIGGER_RISING, "rtc irq", plat_dev);	if (ret)		return dev_err_probe(&plat_dev->dev, ret, "devm_request_irq failed:\n"); 	sp_rtc->rtcclk = devm_clk_get(&plat_dev->dev, NULL);	if (IS_ERR(sp_rtc->rtcclk))		return dev_err_probe(&plat_dev->dev, PTR_ERR(sp_rtc->rtcclk),					    "devm_clk_get fail\n"); 	sp_rtc->rstc = devm_reset_control_get_exclusive(&plat_dev->dev, NULL);	if (IS_ERR(sp_rtc->rstc))		return dev_err_probe(&plat_dev->dev, PTR_ERR(sp_rtc->rstc),					    "failed to retrieve reset controller\n"); 	ret = clk_prepare_enable(sp_rtc->rtcclk);	if (ret)		goto free_clk; 	ret = reset_control_deassert(sp_rtc->rstc);	if (ret)		goto free_reset_assert; 	device_init_wakeup(&plat_dev->dev, true);	dev_set_drvdata(&plat_dev->dev, sp_rtc); 	sp_rtc->rtc = devm_rtc_allocate_device(&plat_dev->dev);	if (IS_ERR(sp_rtc->rtc)) {		ret = PTR_ERR(sp_rtc->rtc);		goto free_reset_assert;	} 	sp_rtc->rtc->range_max = U32_MAX;	sp_rtc->rtc->range_min = 0;	sp_rtc->rtc->ops = &sp_rtc_ops; 	ret = devm_rtc_register_device(sp_rtc->rtc);	if (ret)		goto free_reset_assert; 	/* Setup trickle charger */	if (plat_dev->dev.of_node)		sp_rtc_set_trickle_charger(plat_dev->dev); 	/* Keep RTC from system reset */	writel(DIS_SYS_RST_RTC_MASK_BIT | DIS_SYS_RST_RTC, sp_rtc->reg_base + RTC_CTRL); 	return 0; free_reset_assert:	reset_control_assert(sp_rtc->rstc);free_clk:	clk_disable_unprepare(sp_rtc->rtcclk); 	return ret;} static void sp_rtc_remove(struct platform_device *plat_dev){	struct sunplus_rtc *sp_rtc = dev_get_drvdata(&plat_dev->dev); 	device_init_wakeup(&plat_dev->dev, false);	reset_control_assert(sp_rtc->rstc);	clk_disable_unprepare(sp_rtc->rtcclk);} #ifdef CONFIG_PM_SLEEPstatic int sp_rtc_suspend(struct device *dev){	struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev); 	if (device_may_wakeup(dev))		enable_irq_wake(sp_rtc->irq); 	return 0;} static int sp_rtc_resume(struct device *dev){	struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev); 	if (device_may_wakeup(dev))		disable_irq_wake(sp_rtc->irq); 	return 0;}#endif static const struct of_device_id sp_rtc_of_match[] = {	{ .compatible = "sunplus,sp7021-rtc" },	{ /* sentinel */ }};MODULE_DEVICE_TABLE(of, sp_rtc_of_match); static SIMPLE_DEV_PM_OPS(sp_rtc_pm_ops, sp_rtc_suspend, sp_rtc_resume); static struct platform_driver sp_rtc_driver = {	.probe   = sp_rtc_probe,	.remove = sp_rtc_remove,	.driver  = {		.name	= "sp7021-rtc",		.of_match_table = sp_rtc_of_match,		.pm	= &sp_rtc_pm_ops,	},};module_platform_driver(sp_rtc_driver); MODULE_AUTHOR("Vincent Shih <vincent.sunplus@gmail.com>");MODULE_DESCRIPTION("Sunplus RTC driver");MODULE_LICENSE("GPL v2");