Merge tag 'rtc-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
 "There is an unusual amount of new drivers this cycle, and this
  explains the number of insertions.

  Other than that, the changes are the usual fixes and feature addition.

  Subsystem updates:
   - new quartz-load-femtofarads DT property for quartz load capacitance
   - remove rtc_class_ops.read_callback

  New drivers:
   - Abracon AB-RTCMC-32.768kHz-EOZ9
   - Amlogic Meson RTC
   - Cadence RTC IP
   - Microcrystal RV3028
   - Whwave sd3078

  Driver updates:
   - cmos: ignore bogus century byte
   - ds1307: rework rx8130 support
   - isl1208: add isl1209 support, nvmem support
   - rs5C372: report invalid time when the oscillator stopped
   - rx8581: add rx8571 support"

* tag 'rtc-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (66 commits)
  rtc: pic32: convert to SPDX identifier
  rtc: pic32: let the core handle range
  rtc: pic32: convert to devm_rtc_allocate_device
  rtc: update my email address
  rtc: rv8803: convert to SPDX identifier
  rtc: rv8803: let the core handle range
  rtc: tx4939: convert to SPDX identifier
  rtc: tx4939: use .set_time
  rtc: tx4939: switch to rtc_time64_to_tm/rtc_tm_to_time64
  rtc: tx4939: set range
  rtc: tx4939: remove useless test
  rtc: zynqmp: let the core handle range
  rtc: zynqmp: fix possible race condition
  rtc: imx-sc: use rtc_time64_to_tm
  rtc: rx8581: Add support for Epson rx8571 RTC
  dt-bindings: rtc: add rx8571 compatible
  rtc: pcf85063: remove dead code
  rtc: remove rtc_class_ops.read_callback
  rtc: add AB-RTCMC-32.768kHz-EOZ9 RTC support
  dt-bindings: rtc: add ABEOZ9
  ...

1 files changed, 423 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-cadence.c b/drivers/rtc/rtc-cadence.c
new file mode 100644
index 000000000000..3b7d643c8a63
--- /dev/null
+++ b/drivers/rtc/rtc-cadence.c
@@ -0,0 +1,423 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Copyright 2019 Cadence
+ *
+ * Authors:
+ *  Jan Kotas <jank@cadence.com>
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/io.h>
+#include <linux/rtc.h>
+#include <linux/clk.h>
+#include <linux/bcd.h>
+#include <linux/bitfield.h>
+#include <linux/interrupt.h>
+#include <linux/pm_wakeirq.h>
+
+/* Registers */
+#define CDNS_RTC_CTLR		0x00
+#define CDNS_RTC_HMR		0x04
+#define CDNS_RTC_TIMR		0x08
+#define CDNS_RTC_CALR		0x0C
+#define CDNS_RTC_TIMAR		0x10
+#define CDNS_RTC_CALAR		0x14
+#define CDNS_RTC_AENR		0x18
+#define CDNS_RTC_EFLR		0x1C
+#define CDNS_RTC_IENR		0x20
+#define CDNS_RTC_IDISR		0x24
+#define CDNS_RTC_IMSKR		0x28
+#define CDNS_RTC_STSR		0x2C
+#define CDNS_RTC_KRTCR		0x30
+
+/* Control */
+#define CDNS_RTC_CTLR_TIME	BIT(0)
+#define CDNS_RTC_CTLR_CAL	BIT(1)
+#define CDNS_RTC_CTLR_TIME_CAL	(CDNS_RTC_CTLR_TIME | CDNS_RTC_CTLR_CAL)
+
+/* Status */
+#define CDNS_RTC_STSR_VT	BIT(0)
+#define CDNS_RTC_STSR_VC	BIT(1)
+#define CDNS_RTC_STSR_VTA	BIT(2)
+#define CDNS_RTC_STSR_VCA	BIT(3)
+#define CDNS_RTC_STSR_VT_VC	(CDNS_RTC_STSR_VT | CDNS_RTC_STSR_VC)
+#define CDNS_RTC_STSR_VTA_VCA	(CDNS_RTC_STSR_VTA | CDNS_RTC_STSR_VCA)
+
+/* Keep RTC */
+#define CDNS_RTC_KRTCR_KRTC	BIT(0)
+
+/* Alarm, Event, Interrupt */
+#define CDNS_RTC_AEI_HOS	BIT(0)
+#define CDNS_RTC_AEI_SEC	BIT(1)
+#define CDNS_RTC_AEI_MIN	BIT(2)
+#define CDNS_RTC_AEI_HOUR	BIT(3)
+#define CDNS_RTC_AEI_DATE	BIT(4)
+#define CDNS_RTC_AEI_MNTH	BIT(5)
+#define CDNS_RTC_AEI_ALRM	BIT(6)
+
+/* Time */
+#define CDNS_RTC_TIME_H		GENMASK(7, 0)
+#define CDNS_RTC_TIME_S		GENMASK(14, 8)
+#define CDNS_RTC_TIME_M		GENMASK(22, 16)
+#define CDNS_RTC_TIME_HR	GENMASK(29, 24)
+#define CDNS_RTC_TIME_PM	BIT(30)
+#define CDNS_RTC_TIME_CH	BIT(31)
+
+/* Calendar */
+#define CDNS_RTC_CAL_DAY	GENMASK(2, 0)
+#define CDNS_RTC_CAL_M		GENMASK(7, 3)
+#define CDNS_RTC_CAL_D		GENMASK(13, 8)
+#define CDNS_RTC_CAL_Y		GENMASK(23, 16)
+#define CDNS_RTC_CAL_C		GENMASK(29, 24)
+#define CDNS_RTC_CAL_CH		BIT(31)
+
+#define CDNS_RTC_MAX_REGS_TRIES	3
+
+struct cdns_rtc {
+	struct rtc_device *rtc_dev;
+	struct clk *pclk;
+	struct clk *ref_clk;
+	void __iomem *regs;
+	int irq;
+};
+
+static void cdns_rtc_set_enabled(struct cdns_rtc *crtc, bool enabled)
+{
+	u32 reg = enabled ? 0x0 : CDNS_RTC_CTLR_TIME_CAL;
+
+	writel(reg, crtc->regs + CDNS_RTC_CTLR);
+}
+
+static bool cdns_rtc_get_enabled(struct cdns_rtc *crtc)
+{
+	return !(readl(crtc->regs + CDNS_RTC_CTLR) & CDNS_RTC_CTLR_TIME_CAL);
+}
+
+static irqreturn_t cdns_rtc_irq_handler(int irq, void *id)
+{
+	struct device *dev = id;
+	struct cdns_rtc *crtc = dev_get_drvdata(dev);
+
+	/* Reading the register clears it */
+	if (!(readl(crtc->regs + CDNS_RTC_EFLR) & CDNS_RTC_AEI_ALRM))
+		return IRQ_NONE;
+
+	rtc_update_irq(crtc->rtc_dev, 1, RTC_IRQF | RTC_AF);
+	return IRQ_HANDLED;
+}
+
+static u32 cdns_rtc_time2reg(struct rtc_time *tm)
+{
+	return FIELD_PREP(CDNS_RTC_TIME_S,  bin2bcd(tm->tm_sec))
+	     | FIELD_PREP(CDNS_RTC_TIME_M,  bin2bcd(tm->tm_min))
+	     | FIELD_PREP(CDNS_RTC_TIME_HR, bin2bcd(tm->tm_hour));
+}
+
+static void cdns_rtc_reg2time(u32 reg, struct rtc_time *tm)
+{
+	tm->tm_sec  = bcd2bin(FIELD_GET(CDNS_RTC_TIME_S, reg));
+	tm->tm_min  = bcd2bin(FIELD_GET(CDNS_RTC_TIME_M, reg));
+	tm->tm_hour = bcd2bin(FIELD_GET(CDNS_RTC_TIME_HR, reg));
+}
+
+static int cdns_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	struct cdns_rtc *crtc = dev_get_drvdata(dev);
+	u32 reg;
+
+	/* If the RTC is disabled, assume the values are invalid */
+	if (!cdns_rtc_get_enabled(crtc))
+		return -EINVAL;
+
+	cdns_rtc_set_enabled(crtc, false);
+
+	reg = readl(crtc->regs + CDNS_RTC_TIMR);
+	cdns_rtc_reg2time(reg, tm);
+
+	reg = readl(crtc->regs + CDNS_RTC_CALR);
+	tm->tm_mday = bcd2bin(FIELD_GET(CDNS_RTC_CAL_D, reg));
+	tm->tm_mon  = bcd2bin(FIELD_GET(CDNS_RTC_CAL_M, reg)) - 1;
+	tm->tm_year = bcd2bin(FIELD_GET(CDNS_RTC_CAL_Y, reg))
+		    + bcd2bin(FIELD_GET(CDNS_RTC_CAL_C, reg)) * 100 - 1900;
+	tm->tm_wday = bcd2bin(FIELD_GET(CDNS_RTC_CAL_DAY, reg)) - 1;
+
+	cdns_rtc_set_enabled(crtc, true);
+	return 0;
+}
+
+static int cdns_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	struct cdns_rtc *crtc = dev_get_drvdata(dev);
+	u32 timr, calr, stsr;
+	int ret = -EIO;
+	int year = tm->tm_year + 1900;
+	int tries;
+
+	cdns_rtc_set_enabled(crtc, false);
+
+	timr = cdns_rtc_time2reg(tm);
+
+	calr = FIELD_PREP(CDNS_RTC_CAL_D, bin2bcd(tm->tm_mday))
+	     | FIELD_PREP(CDNS_RTC_CAL_M, bin2bcd(tm->tm_mon + 1))
+	     | FIELD_PREP(CDNS_RTC_CAL_Y, bin2bcd(year % 100))
+	     | FIELD_PREP(CDNS_RTC_CAL_C, bin2bcd(year / 100))
+	     | FIELD_PREP(CDNS_RTC_CAL_DAY, tm->tm_wday + 1);
+
+	/* Update registers, check valid flags */
+	for (tries = 0; tries < CDNS_RTC_MAX_REGS_TRIES; tries++) {
+		writel(timr, crtc->regs + CDNS_RTC_TIMR);
+		writel(calr, crtc->regs + CDNS_RTC_CALR);
+		stsr = readl(crtc->regs + CDNS_RTC_STSR);
+
+		if ((stsr & CDNS_RTC_STSR_VT_VC) == CDNS_RTC_STSR_VT_VC) {
+			ret = 0;
+			break;
+		}
+	}
+
+	cdns_rtc_set_enabled(crtc, true);
+	return ret;
+}
+
+static int cdns_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+	struct cdns_rtc *crtc = dev_get_drvdata(dev);
+
+	if (enabled) {
+		writel((CDNS_RTC_AEI_SEC | CDNS_RTC_AEI_MIN | CDNS_RTC_AEI_HOUR
+			| CDNS_RTC_AEI_DATE | CDNS_RTC_AEI_MNTH),
+		       crtc->regs + CDNS_RTC_AENR);
+		writel(CDNS_RTC_AEI_ALRM, crtc->regs + CDNS_RTC_IENR);
+	} else {
+		writel(0, crtc->regs + CDNS_RTC_AENR);
+		writel(CDNS_RTC_AEI_ALRM, crtc->regs + CDNS_RTC_IDISR);
+	}
+
+	return 0;
+}
+
+static int cdns_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+	struct cdns_rtc *crtc = dev_get_drvdata(dev);
+	u32 reg;
+
+	reg = readl(crtc->regs + CDNS_RTC_TIMAR);
+	cdns_rtc_reg2time(reg, &alarm->time);
+
+	reg = readl(crtc->regs + CDNS_RTC_CALAR);
+	alarm->time.tm_mday = bcd2bin(FIELD_GET(CDNS_RTC_CAL_D, reg));
+	alarm->time.tm_mon  = bcd2bin(FIELD_GET(CDNS_RTC_CAL_M, reg)) - 1;
+
+	return 0;
+}
+
+static int cdns_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+	struct cdns_rtc *crtc = dev_get_drvdata(dev);
+	int ret = -EIO;
+	int tries;
+	u32 timar, calar, stsr;
+
+	cdns_rtc_alarm_irq_enable(dev, 0);
+
+	timar = cdns_rtc_time2reg(&alarm->time);
+	calar = FIELD_PREP(CDNS_RTC_CAL_D, bin2bcd(alarm->time.tm_mday))
+	      | FIELD_PREP(CDNS_RTC_CAL_M, bin2bcd(alarm->time.tm_mon + 1));
+
+	/* Update registers, check valid alarm flags */
+	for (tries = 0; tries < CDNS_RTC_MAX_REGS_TRIES; tries++) {
+		writel(timar, crtc->regs + CDNS_RTC_TIMAR);
+		writel(calar, crtc->regs + CDNS_RTC_CALAR);
+		stsr = readl(crtc->regs + CDNS_RTC_STSR);
+
+		if ((stsr & CDNS_RTC_STSR_VTA_VCA) == CDNS_RTC_STSR_VTA_VCA) {
+			ret = 0;
+			break;
+		}
+	}
+
+	if (!ret)
+		cdns_rtc_alarm_irq_enable(dev, alarm->enabled);
+	return ret;
+}
+
+static const struct rtc_class_ops cdns_rtc_ops = {
+	.read_time	= cdns_rtc_read_time,
+	.set_time	= cdns_rtc_set_time,
+	.read_alarm	= cdns_rtc_read_alarm,
+	.set_alarm	= cdns_rtc_set_alarm,
+	.alarm_irq_enable = cdns_rtc_alarm_irq_enable,
+};
+
+static int cdns_rtc_probe(struct platform_device *pdev)
+{
+	struct cdns_rtc *crtc;
+	struct resource *res;
+	int ret;
+	unsigned long ref_clk_freq;
+
+	crtc = devm_kzalloc(&pdev->dev, sizeof(*crtc), GFP_KERNEL);
+	if (!crtc)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	crtc->regs = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(crtc->regs))
+		return PTR_ERR(crtc->regs);
+
+	crtc->irq = platform_get_irq(pdev, 0);
+	if (crtc->irq < 0)
+		return -EINVAL;
+
+	crtc->pclk = devm_clk_get(&pdev->dev, "pclk");
+	if (IS_ERR(crtc->pclk)) {
+		ret = PTR_ERR(crtc->pclk);
+		dev_err(&pdev->dev,
+			"Failed to retrieve the peripheral clock, %d\n", ret);
+		return ret;
+	}
+
+	crtc->ref_clk = devm_clk_get(&pdev->dev, "ref_clk");
+	if (IS_ERR(crtc->ref_clk)) {
+		ret = PTR_ERR(crtc->ref_clk);
+		dev_err(&pdev->dev,
+			"Failed to retrieve the reference clock, %d\n", ret);
+		return ret;
+	}
+
+	crtc->rtc_dev = devm_rtc_allocate_device(&pdev->dev);
+	if (IS_ERR(crtc->rtc_dev)) {
+		ret = PTR_ERR(crtc->rtc_dev);
+		dev_err(&pdev->dev,
+			"Failed to allocate the RTC device, %d\n", ret);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, crtc);
+
+	ret = clk_prepare_enable(crtc->pclk);
+	if (ret) {
+		dev_err(&pdev->dev,
+			"Failed to enable the peripheral clock, %d\n", ret);
+		return ret;
+	}
+
+	ret = clk_prepare_enable(crtc->ref_clk);
+	if (ret) {
+		dev_err(&pdev->dev,
+			"Failed to enable the reference clock, %d\n", ret);
+		goto err_disable_pclk;
+	}
+
+	ref_clk_freq = clk_get_rate(crtc->ref_clk);
+	if ((ref_clk_freq != 1) && (ref_clk_freq != 100)) {
+		dev_err(&pdev->dev,
+			"Invalid reference clock frequency %lu Hz.\n",
+			ref_clk_freq);
+		ret = -EINVAL;
+		goto err_disable_ref_clk;
+	}
+
+	ret = devm_request_irq(&pdev->dev, crtc->irq,
+			       cdns_rtc_irq_handler, 0,
+			       dev_name(&pdev->dev), &pdev->dev);
+	if (ret) {
+		dev_err(&pdev->dev,
+			"Failed to request interrupt for the device, %d\n",
+			ret);
+		goto err_disable_ref_clk;
+	}
+
+	/* The RTC supports 01.01.1900 - 31.12.2999 */
+	crtc->rtc_dev->range_min = mktime64(1900,  1,  1,  0,  0,  0);
+	crtc->rtc_dev->range_max = mktime64(2999, 12, 31, 23, 59, 59);
+
+	crtc->rtc_dev->ops = &cdns_rtc_ops;
+	device_init_wakeup(&pdev->dev, true);
+
+	/* Always use 24-hour mode and keep the RTC values */
+	writel(0, crtc->regs + CDNS_RTC_HMR);
+	writel(CDNS_RTC_KRTCR_KRTC, crtc->regs + CDNS_RTC_KRTCR);
+
+	ret = rtc_register_device(crtc->rtc_dev);
+	if (ret) {
+		dev_err(&pdev->dev,
+			"Failed to register the RTC device, %d\n", ret);
+		goto err_disable_wakeup;
+	}
+
+	return 0;
+
+err_disable_wakeup:
+	device_init_wakeup(&pdev->dev, false);
+
+err_disable_ref_clk:
+	clk_disable_unprepare(crtc->ref_clk);
+
+err_disable_pclk:
+	clk_disable_unprepare(crtc->pclk);
+
+	return ret;
+}
+
+static int cdns_rtc_remove(struct platform_device *pdev)
+{
+	struct cdns_rtc *crtc = platform_get_drvdata(pdev);
+
+	cdns_rtc_alarm_irq_enable(&pdev->dev, 0);
+	device_init_wakeup(&pdev->dev, 0);
+
+	clk_disable_unprepare(crtc->pclk);
+	clk_disable_unprepare(crtc->ref_clk);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int cdns_rtc_suspend(struct device *dev)
+{
+	struct cdns_rtc *crtc = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev))
+		enable_irq_wake(crtc->irq);
+
+	return 0;
+}
+
+static int cdns_rtc_resume(struct device *dev)
+{
+	struct cdns_rtc *crtc = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev))
+		disable_irq_wake(crtc->irq);
+
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(cdns_rtc_pm_ops, cdns_rtc_suspend, cdns_rtc_resume);
+
+static const struct of_device_id cdns_rtc_of_match[] = {
+	{ .compatible = "cdns,rtc-r109v3" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, cdns_rtc_of_match);
+
+static struct platform_driver cdns_rtc_driver = {
+	.driver = {
+		.name = "cdns-rtc",
+		.of_match_table = cdns_rtc_of_match,
+		.pm = &cdns_rtc_pm_ops,
+	},
+	.probe = cdns_rtc_probe,
+	.remove = cdns_rtc_remove,
+};
+module_platform_driver(cdns_rtc_driver);
+
+MODULE_AUTHOR("Jan Kotas <jank@cadence.com>");
+MODULE_DESCRIPTION("Cadence RTC driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:cdns-rtc");