1 files changed, 219 insertions, 107 deletions

diff --git a/drivers/rtc/rtc-jz4740.c b/drivers/rtc/rtc-jz4740.c
index 1b126d2513de..11fce47be780 100644
--- a/drivers/rtc/rtc-jz4740.c
+++ b/drivers/rtc/rtc-jz4740.c
@@ -1,23 +1,21 @@
+// SPDX-License-Identifier: GPL-2.0+
 /*
  *  Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
  *  Copyright (C) 2010, Paul Cercueil <paul@crapouillou.net>
  *	 JZ4740 SoC RTC driver
- *
- *  This program is free software; you can redistribute it and/or modify it
- *  under  the terms of  the GNU General Public License as published by the
- *  Free Software Foundation;  either version 2 of the License, or (at your
- *  option) any later version.
- *
- *  You should have received a copy of the GNU General Public License along
- *  with this program; if not, write to the Free Software Foundation, Inc.,
- *  675 Mass Ave, Cambridge, MA 02139, USA.
- *
  */
 
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
 #include <linux/io.h>
+#include <linux/iopoll.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/pm_wakeirq.h>
+#include <linux/property.h>
+#include <linux/reboot.h>
 #include <linux/rtc.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
@@ -27,7 +25,14 @@
 #define JZ_REG_RTC_SEC_ALARM	0x08
 #define JZ_REG_RTC_REGULATOR	0x0C
 #define JZ_REG_RTC_HIBERNATE	0x20
+#define JZ_REG_RTC_WAKEUP_FILTER	0x24
+#define JZ_REG_RTC_RESET_COUNTER	0x28
 #define JZ_REG_RTC_SCRATCHPAD	0x34
+#define JZ_REG_RTC_CKPCR	0x40
+
+/* The following are present on the jz4780 */
+#define JZ_REG_RTC_WENR	0x3C
+#define JZ_RTC_WENR_WEN	BIT(31)
 
 #define JZ_RTC_CTRL_WRDY	BIT(7)
 #define JZ_RTC_CTRL_1HZ		BIT(6)
@@ -37,17 +42,34 @@
 #define JZ_RTC_CTRL_AE		BIT(2)
 #define JZ_RTC_CTRL_ENABLE	BIT(0)
 
+/* Magic value to enable writes on jz4780 */
+#define JZ_RTC_WENR_MAGIC	0xA55A
+
+#define JZ_RTC_WAKEUP_FILTER_MASK	0x0000FFE0
+#define JZ_RTC_RESET_COUNTER_MASK	0x00000FE0
+
+#define JZ_RTC_CKPCR_CK32PULL_DIS	BIT(4)
+#define JZ_RTC_CKPCR_CK32CTL_EN		(BIT(2) | BIT(1))
+
+enum jz4740_rtc_type {
+	ID_JZ4740,
+	ID_JZ4760,
+	ID_JZ4780,
+};
+
 struct jz4740_rtc {
-	struct resource *mem;
 	void __iomem *base;
+	enum jz4740_rtc_type type;
 
 	struct rtc_device *rtc;
 
-	int irq;
+	struct clk_hw clk32k;
 
 	spinlock_t lock;
 };
 
+static struct device *dev_for_power_off;
+
 static inline uint32_t jz4740_rtc_reg_read(struct jz4740_rtc *rtc, size_t reg)
 {
 	return readl(rtc->base + reg);
@@ -56,20 +78,35 @@ static inline uint32_t jz4740_rtc_reg_read(struct jz4740_rtc *rtc, size_t reg)
 static int jz4740_rtc_wait_write_ready(struct jz4740_rtc *rtc)
 {
 	uint32_t ctrl;
-	int timeout = 1000;
 
-	do {
-		ctrl = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_CTRL);
-	} while (!(ctrl & JZ_RTC_CTRL_WRDY) && --timeout);
+	return readl_poll_timeout(rtc->base + JZ_REG_RTC_CTRL, ctrl,
+				  ctrl & JZ_RTC_CTRL_WRDY, 0, 1000);
+}
 
-	return timeout ? 0 : -EIO;
+static inline int jz4780_rtc_enable_write(struct jz4740_rtc *rtc)
+{
+	uint32_t ctrl;
+	int ret;
+
+	ret = jz4740_rtc_wait_write_ready(rtc);
+	if (ret != 0)
+		return ret;
+
+	writel(JZ_RTC_WENR_MAGIC, rtc->base + JZ_REG_RTC_WENR);
+
+	return readl_poll_timeout(rtc->base + JZ_REG_RTC_WENR, ctrl,
+				  ctrl & JZ_RTC_WENR_WEN, 0, 1000);
 }
 
 static inline int jz4740_rtc_reg_write(struct jz4740_rtc *rtc, size_t reg,
 	uint32_t val)
 {
-	int ret;
-	ret = jz4740_rtc_wait_write_ready(rtc);
+	int ret = 0;
+
+	if (rtc->type >= ID_JZ4760)
+		ret = jz4780_rtc_enable_write(rtc);
+	if (ret == 0)
+		ret = jz4740_rtc_wait_write_ready(rtc);
 	if (ret == 0)
 		writel(val, rtc->base + reg);
 
@@ -108,6 +145,9 @@ static int jz4740_rtc_read_time(struct device *dev, struct rtc_time *time)
 	uint32_t secs, secs2;
 	int timeout = 5;
 
+	if (jz4740_rtc_reg_read(rtc, JZ_REG_RTC_SCRATCHPAD) != 0x12345678)
+		return -EINVAL;
+
 	/* If the seconds register is read while it is updated, it can contain a
 	 * bogus value. This can be avoided by making sure that two consecutive
 	 * reads have the same value.
@@ -123,16 +163,21 @@ static int jz4740_rtc_read_time(struct device *dev, struct rtc_time *time)
 	if (timeout == 0)
 		return -EIO;
 
-	rtc_time_to_tm(secs, time);
+	rtc_time64_to_tm(secs, time);
 
-	return rtc_valid_tm(time);
+	return 0;
 }
 
-static int jz4740_rtc_set_mmss(struct device *dev, unsigned long secs)
+static int jz4740_rtc_set_time(struct device *dev, struct rtc_time *time)
 {
 	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
+	int ret;
 
-	return jz4740_rtc_reg_write(rtc, JZ_REG_RTC_SEC, secs);
+	ret = jz4740_rtc_reg_write(rtc, JZ_REG_RTC_SEC, rtc_tm_to_time64(time));
+	if (ret)
+		return ret;
+
+	return jz4740_rtc_reg_write(rtc, JZ_REG_RTC_SCRATCHPAD, 0x12345678);
 }
 
 static int jz4740_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
@@ -148,18 +193,16 @@ static int jz4740_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 	alrm->enabled = !!(ctrl & JZ_RTC_CTRL_AE);
 	alrm->pending = !!(ctrl & JZ_RTC_CTRL_AF);
 
-	rtc_time_to_tm(secs, &alrm->time);
+	rtc_time64_to_tm(secs, &alrm->time);
 
-	return rtc_valid_tm(&alrm->time);
+	return 0;
 }
 
 static int jz4740_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 {
 	int ret;
 	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
-	unsigned long secs;
-
-	rtc_tm_to_time(&alrm->time, &secs);
+	uint32_t secs = lower_32_bits(rtc_tm_to_time64(&alrm->time));
 
 	ret = jz4740_rtc_reg_write(rtc, JZ_REG_RTC_SEC_ALARM, secs);
 	if (!ret)
@@ -175,9 +218,9 @@ static int jz4740_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
 	return jz4740_rtc_ctrl_set_bits(rtc, JZ_RTC_CTRL_AF_IRQ, enable);
 }
 
-static struct rtc_class_ops jz4740_rtc_ops = {
+static const struct rtc_class_ops jz4740_rtc_ops = {
 	.read_time	= jz4740_rtc_read_time,
-	.set_mmss	= jz4740_rtc_set_mmss,
+	.set_time	= jz4740_rtc_set_time,
 	.read_alarm	= jz4740_rtc_read_alarm,
 	.set_alarm	= jz4740_rtc_set_alarm,
 	.alarm_irq_enable = jz4740_rtc_alarm_irq_enable,
@@ -204,118 +247,188 @@ static irqreturn_t jz4740_rtc_irq(int irq, void *data)
 	return IRQ_HANDLED;
 }
 
-void jz4740_rtc_poweroff(struct device *dev)
+static void jz4740_rtc_poweroff(struct device *dev)
 {
 	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
 	jz4740_rtc_reg_write(rtc, JZ_REG_RTC_HIBERNATE, 1);
 }
-EXPORT_SYMBOL_GPL(jz4740_rtc_poweroff);
+
+static void jz4740_rtc_power_off(void)
+{
+	jz4740_rtc_poweroff(dev_for_power_off);
+	kernel_halt();
+}
+
+static const struct of_device_id jz4740_rtc_of_match[] = {
+	{ .compatible = "ingenic,jz4740-rtc", .data = (void *)ID_JZ4740 },
+	{ .compatible = "ingenic,jz4760-rtc", .data = (void *)ID_JZ4760 },
+	{ .compatible = "ingenic,jz4770-rtc", .data = (void *)ID_JZ4780 },
+	{ .compatible = "ingenic,jz4780-rtc", .data = (void *)ID_JZ4780 },
+	{},
+};
+MODULE_DEVICE_TABLE(of, jz4740_rtc_of_match);
+
+static void jz4740_rtc_set_wakeup_params(struct jz4740_rtc *rtc,
+					 struct device_node *np,
+					 unsigned long rate)
+{
+	unsigned long wakeup_ticks, reset_ticks;
+	unsigned int min_wakeup_pin_assert_time = 60; /* Default: 60ms */
+	unsigned int reset_pin_assert_time = 100; /* Default: 100ms */
+
+	of_property_read_u32(np, "ingenic,reset-pin-assert-time-ms",
+			     &reset_pin_assert_time);
+	of_property_read_u32(np, "ingenic,min-wakeup-pin-assert-time-ms",
+			     &min_wakeup_pin_assert_time);
+
+	/*
+	 * Set minimum wakeup pin assertion time: 100 ms.
+	 * Range is 0 to 2 sec if RTC is clocked at 32 kHz.
+	 */
+	wakeup_ticks = (min_wakeup_pin_assert_time * rate) / 1000;
+	if (wakeup_ticks < JZ_RTC_WAKEUP_FILTER_MASK)
+		wakeup_ticks &= JZ_RTC_WAKEUP_FILTER_MASK;
+	else
+		wakeup_ticks = JZ_RTC_WAKEUP_FILTER_MASK;
+	jz4740_rtc_reg_write(rtc, JZ_REG_RTC_WAKEUP_FILTER, wakeup_ticks);
+
+	/*
+	 * Set reset pin low-level assertion time after wakeup: 60 ms.
+	 * Range is 0 to 125 ms if RTC is clocked at 32 kHz.
+	 */
+	reset_ticks = (reset_pin_assert_time * rate) / 1000;
+	if (reset_ticks < JZ_RTC_RESET_COUNTER_MASK)
+		reset_ticks &= JZ_RTC_RESET_COUNTER_MASK;
+	else
+		reset_ticks = JZ_RTC_RESET_COUNTER_MASK;
+	jz4740_rtc_reg_write(rtc, JZ_REG_RTC_RESET_COUNTER, reset_ticks);
+}
+
+static int jz4740_rtc_clk32k_enable(struct clk_hw *hw)
+{
+	struct jz4740_rtc *rtc = container_of(hw, struct jz4740_rtc, clk32k);
+
+	return jz4740_rtc_reg_write(rtc, JZ_REG_RTC_CKPCR,
+				    JZ_RTC_CKPCR_CK32PULL_DIS |
+				    JZ_RTC_CKPCR_CK32CTL_EN);
+}
+
+static void jz4740_rtc_clk32k_disable(struct clk_hw *hw)
+{
+	struct jz4740_rtc *rtc = container_of(hw, struct jz4740_rtc, clk32k);
+
+	jz4740_rtc_reg_write(rtc, JZ_REG_RTC_CKPCR, 0);
+}
+
+static int jz4740_rtc_clk32k_is_enabled(struct clk_hw *hw)
+{
+	struct jz4740_rtc *rtc = container_of(hw, struct jz4740_rtc, clk32k);
+	u32 ckpcr;
+
+	ckpcr = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_CKPCR);
+
+	return !!(ckpcr & JZ_RTC_CKPCR_CK32CTL_EN);
+}
+
+static const struct clk_ops jz4740_rtc_clk32k_ops = {
+	.enable = jz4740_rtc_clk32k_enable,
+	.disable = jz4740_rtc_clk32k_disable,
+	.is_enabled = jz4740_rtc_clk32k_is_enabled,
+};
 
 static int jz4740_rtc_probe(struct platform_device *pdev)
 {
-	int ret;
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
 	struct jz4740_rtc *rtc;
-	uint32_t scratchpad;
+	unsigned long rate;
+	struct clk *clk;
+	int ret, irq;
 
-	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
+	rtc = devm_kzalloc(dev, sizeof(*rtc), GFP_KERNEL);
 	if (!rtc)
 		return -ENOMEM;
 
-	rtc->irq = platform_get_irq(pdev, 0);
-	if (rtc->irq < 0) {
-		dev_err(&pdev->dev, "Failed to get platform irq\n");
-		return -ENOENT;
-	}
+	rtc->type = (uintptr_t)device_get_match_data(dev);
 
-	rtc->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!rtc->mem) {
-		dev_err(&pdev->dev, "Failed to get platform mmio memory\n");
-		return -ENOENT;
-	}
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
 
-	rtc->mem = devm_request_mem_region(&pdev->dev, rtc->mem->start,
-					resource_size(rtc->mem), pdev->name);
-	if (!rtc->mem) {
-		dev_err(&pdev->dev, "Failed to request mmio memory region\n");
-		return -EBUSY;
-	}
+	rtc->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(rtc->base))
+		return PTR_ERR(rtc->base);
 
-	rtc->base = devm_ioremap_nocache(&pdev->dev, rtc->mem->start,
-					resource_size(rtc->mem));
-	if (!rtc->base) {
-		dev_err(&pdev->dev, "Failed to ioremap mmio memory\n");
-		return -EBUSY;
-	}
+	clk = devm_clk_get_enabled(dev, "rtc");
+	if (IS_ERR(clk))
+		return dev_err_probe(dev, PTR_ERR(clk), "Failed to get RTC clock\n");
 
 	spin_lock_init(&rtc->lock);
 
 	platform_set_drvdata(pdev, rtc);
 
-	device_init_wakeup(&pdev->dev, 1);
+	device_init_wakeup(dev, true);
 
-	rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
-					&jz4740_rtc_ops, THIS_MODULE);
-	if (IS_ERR(rtc->rtc)) {
-		ret = PTR_ERR(rtc->rtc);
-		dev_err(&pdev->dev, "Failed to register rtc device: %d\n", ret);
-		return ret;
-	}
+	ret = dev_pm_set_wake_irq(dev, irq);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to set wake irq\n");
 
-	ret = devm_request_irq(&pdev->dev, rtc->irq, jz4740_rtc_irq, 0,
-				pdev->name, rtc);
-	if (ret) {
-		dev_err(&pdev->dev, "Failed to request rtc irq: %d\n", ret);
+	rtc->rtc = devm_rtc_allocate_device(dev);
+	if (IS_ERR(rtc->rtc))
+		return dev_err_probe(dev, PTR_ERR(rtc->rtc),
+				     "Failed to allocate rtc device\n");
+
+	rtc->rtc->ops = &jz4740_rtc_ops;
+	rtc->rtc->range_max = U32_MAX;
+
+	rate = clk_get_rate(clk);
+	jz4740_rtc_set_wakeup_params(rtc, np, rate);
+
+	/* Each 1 Hz pulse should happen after (rate) ticks */
+	jz4740_rtc_reg_write(rtc, JZ_REG_RTC_REGULATOR, rate - 1);
+
+	ret = devm_rtc_register_device(rtc->rtc);
+	if (ret)
 		return ret;
-	}
 
-	scratchpad = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_SCRATCHPAD);
-	if (scratchpad != 0x12345678) {
-		ret = jz4740_rtc_reg_write(rtc, JZ_REG_RTC_SCRATCHPAD, 0x12345678);
-		ret = jz4740_rtc_reg_write(rtc, JZ_REG_RTC_SEC, 0);
-		if (ret) {
-			dev_err(&pdev->dev, "Could not write write to RTC registers\n");
-			return ret;
-		}
-	}
+	ret = devm_request_irq(dev, irq, jz4740_rtc_irq, 0,
+			       pdev->name, rtc);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to request rtc irq\n");
 
-	return 0;
-}
+	if (of_device_is_system_power_controller(np)) {
+		dev_for_power_off = dev;
 
-#ifdef CONFIG_PM
-static int jz4740_rtc_suspend(struct device *dev)
-{
-	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
+		if (!pm_power_off)
+			pm_power_off = jz4740_rtc_power_off;
+		else
+			dev_warn(dev, "Poweroff handler already present!\n");
+	}
 
-	if (device_may_wakeup(dev))
-		enable_irq_wake(rtc->irq);
-	return 0;
-}
+	if (device_property_present(dev, "#clock-cells")) {
+		rtc->clk32k.init = CLK_HW_INIT_HW("clk32k", __clk_get_hw(clk),
+						  &jz4740_rtc_clk32k_ops, 0);
 
-static int jz4740_rtc_resume(struct device *dev)
-{
-	struct jz4740_rtc *rtc = dev_get_drvdata(dev);
+		ret = devm_clk_hw_register(dev, &rtc->clk32k);
+		if (ret)
+			return dev_err_probe(dev, ret,
+					     "Unable to register clk32k clock\n");
+
+		ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
+						  &rtc->clk32k);
+		if (ret)
+			return dev_err_probe(dev, ret,
+					     "Unable to register clk32k clock provider\n");
+	}
 
-	if (device_may_wakeup(dev))
-		disable_irq_wake(rtc->irq);
 	return 0;
 }
 
-static const struct dev_pm_ops jz4740_pm_ops = {
-	.suspend = jz4740_rtc_suspend,
-	.resume  = jz4740_rtc_resume,
-};
-#define JZ4740_RTC_PM_OPS (&jz4740_pm_ops)
-
-#else
-#define JZ4740_RTC_PM_OPS NULL
-#endif  /* CONFIG_PM */
-
 static struct platform_driver jz4740_rtc_driver = {
 	.probe	 = jz4740_rtc_probe,
 	.driver	 = {
 		.name  = "jz4740-rtc",
-		.owner = THIS_MODULE,
-		.pm    = JZ4740_RTC_PM_OPS,
+		.of_match_table = jz4740_rtc_of_match,
 	},
 };
 
@@ -324,4 +437,3 @@ module_platform_driver(jz4740_rtc_driver);
 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("RTC driver for the JZ4740 SoC\n");
-MODULE_ALIAS("platform:jz4740-rtc");