Merge tag 'rtc-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
 "Subsystem:
   - constify rtc_class_ops structures

 New driver:
   - STM32

 Drivers:
   - armada38x: fix errata, Armada 7K/8K support
   - ds3232: fix wakeup support
   - gemini: DT support
   - m48t86: huge cleanup and platform_data removal
   - mcp795: alarm support
   - sun6i: proper oscillator handling
   - tegra: proper clock handling
   - tps65910: calibration support"

* tag 'rtc-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (44 commits)
  rtc: ds3232: Call device_init_wakeup before device_register
  rtc: pcf2127: bulk read only date and time registers.
  rtc: armada38x: Add support for Armada 7K/8K
  rtc: armada38x: Prepare driver to manage different versions
  rtc: ds3232: Add regmap max_register definition.
  rtc: ds3232: Cleanup whitespace around register and bit definitions.
  rtc: m48t86: remove unused platform_data
  ARM: Orion5x: ts78xx: allow rtc-m48t86 to manage it's own resources
  ARM: Orion5x: ts78xx: remove RTC detection
  ARM: ep93xx: ts72xx: allow rtc-m48t86 to manage its own resources
  rtc: m48t86: verify that the RTC is actually present
  rtc: m48t86: add NVRAM support
  rtc: m48t86: allow driver to manage its resources
  rtc: m48t86: shorten register name defines
  bindings: rtc: correct wrong reference in required properties
  rtc: sun6i: Fix return value check in sun6i_rtc_clk_init()
  rtc: sun6i: extend test coverage
  rtc: sun6i: Fix compatibility with old DT binding
  rtc: snvs: add a missing write sync
  rtc: bq32000: add support to enable disable the trickle charge FET bypass
  ...

1 files changed, 153 insertions, 29 deletions

diff --git a/drivers/rtc/rtc-sun6i.c b/drivers/rtc/rtc-sun6i.c
index c169a2cd4727..39cbc1238b92 100644
--- a/drivers/rtc/rtc-sun6i.c
+++ b/drivers/rtc/rtc-sun6i.c
@@ -20,6 +20,8 @@
  * more details.
  */
 
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
 #include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/fs.h>
@@ -33,15 +35,20 @@
 #include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/rtc.h>
+#include <linux/slab.h>
 #include <linux/types.h>
 
 /* Control register */
 #define SUN6I_LOSC_CTRL				0x0000
+#define SUN6I_LOSC_CTRL_KEY			(0x16aa << 16)
 #define SUN6I_LOSC_CTRL_ALM_DHMS_ACC		BIT(9)
 #define SUN6I_LOSC_CTRL_RTC_HMS_ACC		BIT(8)
 #define SUN6I_LOSC_CTRL_RTC_YMD_ACC		BIT(7)
+#define SUN6I_LOSC_CTRL_EXT_OSC			BIT(0)
 #define SUN6I_LOSC_CTRL_ACC_MASK		GENMASK(9, 7)
 
+#define SUN6I_LOSC_CLK_PRESCAL			0x0008
+
 /* RTC */
 #define SUN6I_RTC_YMD				0x0010
 #define SUN6I_RTC_HMS				0x0014
@@ -114,13 +121,142 @@ struct sun6i_rtc_dev {
 	void __iomem *base;
 	int irq;
 	unsigned long alarm;
+
+	struct clk_hw hw;
+	struct clk_hw *int_osc;
+	struct clk *losc;
+
+	spinlock_t lock;
+};
+
+static struct sun6i_rtc_dev *sun6i_rtc;
+
+static unsigned long sun6i_rtc_osc_recalc_rate(struct clk_hw *hw,
+					       unsigned long parent_rate)
+{
+	struct sun6i_rtc_dev *rtc = container_of(hw, struct sun6i_rtc_dev, hw);
+	u32 val;
+
+	val = readl(rtc->base + SUN6I_LOSC_CTRL);
+	if (val & SUN6I_LOSC_CTRL_EXT_OSC)
+		return parent_rate;
+
+	val = readl(rtc->base + SUN6I_LOSC_CLK_PRESCAL);
+	val &= GENMASK(4, 0);
+
+	return parent_rate / (val + 1);
+}
+
+static u8 sun6i_rtc_osc_get_parent(struct clk_hw *hw)
+{
+	struct sun6i_rtc_dev *rtc = container_of(hw, struct sun6i_rtc_dev, hw);
+
+	return readl(rtc->base + SUN6I_LOSC_CTRL) & SUN6I_LOSC_CTRL_EXT_OSC;
+}
+
+static int sun6i_rtc_osc_set_parent(struct clk_hw *hw, u8 index)
+{
+	struct sun6i_rtc_dev *rtc = container_of(hw, struct sun6i_rtc_dev, hw);
+	unsigned long flags;
+	u32 val;
+
+	if (index > 1)
+		return -EINVAL;
+
+	spin_lock_irqsave(&rtc->lock, flags);
+	val = readl(rtc->base + SUN6I_LOSC_CTRL);
+	val &= ~SUN6I_LOSC_CTRL_EXT_OSC;
+	val |= SUN6I_LOSC_CTRL_KEY;
+	val |= index ? SUN6I_LOSC_CTRL_EXT_OSC : 0;
+	writel(val, rtc->base + SUN6I_LOSC_CTRL);
+	spin_unlock_irqrestore(&rtc->lock, flags);
+
+	return 0;
+}
+
+static const struct clk_ops sun6i_rtc_osc_ops = {
+	.recalc_rate	= sun6i_rtc_osc_recalc_rate,
+
+	.get_parent	= sun6i_rtc_osc_get_parent,
+	.set_parent	= sun6i_rtc_osc_set_parent,
 };
 
+static void __init sun6i_rtc_clk_init(struct device_node *node)
+{
+	struct clk_hw_onecell_data *clk_data;
+	struct sun6i_rtc_dev *rtc;
+	struct clk_init_data init = {
+		.ops		= &sun6i_rtc_osc_ops,
+	};
+	const char *parents[2];
+
+	rtc = kzalloc(sizeof(*rtc), GFP_KERNEL);
+	if (!rtc)
+		return;
+	spin_lock_init(&rtc->lock);
+
+	clk_data = kzalloc(sizeof(*clk_data) + sizeof(*clk_data->hws),
+			   GFP_KERNEL);
+	if (!clk_data)
+		return;
+	spin_lock_init(&rtc->lock);
+
+	rtc->base = of_io_request_and_map(node, 0, of_node_full_name(node));
+	if (IS_ERR(rtc->base)) {
+		pr_crit("Can't map RTC registers");
+		return;
+	}
+
+	/* Switch to the external, more precise, oscillator */
+	writel(SUN6I_LOSC_CTRL_KEY | SUN6I_LOSC_CTRL_EXT_OSC,
+	       rtc->base + SUN6I_LOSC_CTRL);
+
+	/* Yes, I know, this is ugly. */
+	sun6i_rtc = rtc;
+
+	/* Deal with old DTs */
+	if (!of_get_property(node, "clocks", NULL))
+		return;
+
+	rtc->int_osc = clk_hw_register_fixed_rate_with_accuracy(NULL,
+								"rtc-int-osc",
+								NULL, 0,
+								667000,
+								300000000);
+	if (IS_ERR(rtc->int_osc)) {
+		pr_crit("Couldn't register the internal oscillator\n");
+		return;
+	}
+
+	parents[0] = clk_hw_get_name(rtc->int_osc);
+	parents[1] = of_clk_get_parent_name(node, 0);
+
+	rtc->hw.init = &init;
+
+	init.parent_names = parents;
+	init.num_parents = of_clk_get_parent_count(node) + 1;
+	of_property_read_string(node, "clock-output-names", &init.name);
+
+	rtc->losc = clk_register(NULL, &rtc->hw);
+	if (IS_ERR(rtc->losc)) {
+		pr_crit("Couldn't register the LOSC clock\n");
+		return;
+	}
+
+	clk_data->num = 1;
+	clk_data->hws[0] = &rtc->hw;
+	of_clk_add_hw_provider(node, of_clk_hw_onecell_get, clk_data);
+}
+CLK_OF_DECLARE_DRIVER(sun6i_rtc_clk, "allwinner,sun6i-a31-rtc",
+		      sun6i_rtc_clk_init);
+
 static irqreturn_t sun6i_rtc_alarmirq(int irq, void *id)
 {
 	struct sun6i_rtc_dev *chip = (struct sun6i_rtc_dev *) id;
+	irqreturn_t ret = IRQ_NONE;
 	u32 val;
 
+	spin_lock(&chip->lock);
 	val = readl(chip->base + SUN6I_ALRM_IRQ_STA);
 
 	if (val & SUN6I_ALRM_IRQ_STA_CNT_IRQ_PEND) {
@@ -129,10 +265,11 @@ static irqreturn_t sun6i_rtc_alarmirq(int irq, void *id)
 
 		rtc_update_irq(chip->rtc, 1, RTC_AF | RTC_IRQF);
 
-		return IRQ_HANDLED;
+		ret = IRQ_HANDLED;
 	}
+	spin_unlock(&chip->lock);
 
-	return IRQ_NONE;
+	return ret;
 }
 
 static void sun6i_rtc_setaie(int to, struct sun6i_rtc_dev *chip)
@@ -140,6 +277,7 @@ static void sun6i_rtc_setaie(int to, struct sun6i_rtc_dev *chip)
 	u32 alrm_val = 0;
 	u32 alrm_irq_val = 0;
 	u32 alrm_wake_val = 0;
+	unsigned long flags;
 
 	if (to) {
 		alrm_val = SUN6I_ALRM_EN_CNT_EN;
@@ -150,9 +288,11 @@ static void sun6i_rtc_setaie(int to, struct sun6i_rtc_dev *chip)
 		       chip->base + SUN6I_ALRM_IRQ_STA);
 	}
 
+	spin_lock_irqsave(&chip->lock, flags);
 	writel(alrm_val, chip->base + SUN6I_ALRM_EN);
 	writel(alrm_irq_val, chip->base + SUN6I_ALRM_IRQ_EN);
 	writel(alrm_wake_val, chip->base + SUN6I_ALARM_CONFIG);
+	spin_unlock_irqrestore(&chip->lock, flags);
 }
 
 static int sun6i_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
@@ -191,11 +331,15 @@ static int sun6i_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
 static int sun6i_rtc_getalarm(struct device *dev, struct rtc_wkalrm *wkalrm)
 {
 	struct sun6i_rtc_dev *chip = dev_get_drvdata(dev);
+	unsigned long flags;
 	u32 alrm_st;
 	u32 alrm_en;
 
+	spin_lock_irqsave(&chip->lock, flags);
 	alrm_en = readl(chip->base + SUN6I_ALRM_IRQ_EN);
 	alrm_st = readl(chip->base + SUN6I_ALRM_IRQ_STA);
+	spin_unlock_irqrestore(&chip->lock, flags);
+
 	wkalrm->enabled = !!(alrm_en & SUN6I_ALRM_EN_CNT_EN);
 	wkalrm->pending = !!(alrm_st & SUN6I_ALRM_EN_CNT_EN);
 	rtc_time_to_tm(chip->alarm, &wkalrm->time);
@@ -349,22 +493,15 @@ static const struct rtc_class_ops sun6i_rtc_ops = {
 
 static int sun6i_rtc_probe(struct platform_device *pdev)
 {
-	struct sun6i_rtc_dev *chip;
-	struct resource *res;
+	struct sun6i_rtc_dev *chip = sun6i_rtc;
 	int ret;
 
-	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
 	if (!chip)
-		return -ENOMEM;
+		return -ENODEV;
 
 	platform_set_drvdata(pdev, chip);
 	chip->dev = &pdev->dev;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	chip->base = devm_ioremap_resource(&pdev->dev, res);
-	if (IS_ERR(chip->base))
-		return PTR_ERR(chip->base);
-
 	chip->irq = platform_get_irq(pdev, 0);
 	if (chip->irq < 0) {
 		dev_err(&pdev->dev, "No IRQ resource\n");
@@ -404,8 +541,10 @@ static int sun6i_rtc_probe(struct platform_device *pdev)
 	/* disable alarm wakeup */
 	writel(0, chip->base + SUN6I_ALARM_CONFIG);
 
-	chip->rtc = rtc_device_register("rtc-sun6i", &pdev->dev,
-					&sun6i_rtc_ops, THIS_MODULE);
+	clk_prepare_enable(chip->losc);
+
+	chip->rtc = devm_rtc_device_register(&pdev->dev, "rtc-sun6i",
+					     &sun6i_rtc_ops, THIS_MODULE);
 	if (IS_ERR(chip->rtc)) {
 		dev_err(&pdev->dev, "unable to register device\n");
 		return PTR_ERR(chip->rtc);
@@ -416,15 +555,6 @@ static int sun6i_rtc_probe(struct platform_device *pdev)
 	return 0;
 }
 
-static int sun6i_rtc_remove(struct platform_device *pdev)
-{
-	struct sun6i_rtc_dev *chip = platform_get_drvdata(pdev);
-
-	rtc_device_unregister(chip->rtc);
-
-	return 0;
-}
-
 static const struct of_device_id sun6i_rtc_dt_ids[] = {
 	{ .compatible = "allwinner,sun6i-a31-rtc" },
 	{ /* sentinel */ },
@@ -433,15 +563,9 @@ MODULE_DEVICE_TABLE(of, sun6i_rtc_dt_ids);
 
 static struct platform_driver sun6i_rtc_driver = {
 	.probe		= sun6i_rtc_probe,
-	.remove		= sun6i_rtc_remove,
 	.driver		= {
 		.name		= "sun6i-rtc",
 		.of_match_table = sun6i_rtc_dt_ids,
 	},
 };
-
-module_platform_driver(sun6i_rtc_driver);
-
-MODULE_DESCRIPTION("sun6i RTC driver");
-MODULE_AUTHOR("Chen-Yu Tsai <wens@csie.org>");
-MODULE_LICENSE("GPL");
+builtin_platform_driver(sun6i_rtc_driver);