Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/rtc/rtc-sun6i.c b/drivers/rtc/rtc-sun6i.c
index 2cd5a7b..5e2bd9f 100644
--- a/drivers/rtc/rtc-sun6i.c
+++ b/drivers/rtc/rtc-sun6i.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * An RTC driver for Allwinner A31/A23
  *
@@ -8,16 +9,6 @@
  * An RTC driver for Allwinner A10/A20
  *
  * Copyright (c) 2013, Carlo Caione <carlo.caione@gmail.com>
- *
- * 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.
- *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
- * more details.
  */
 
 #include <linux/clk.h>
@@ -41,9 +32,11 @@
 /* Control register */
 #define SUN6I_LOSC_CTRL				0x0000
 #define SUN6I_LOSC_CTRL_KEY			(0x16aa << 16)
+#define SUN6I_LOSC_CTRL_AUTO_SWT_BYPASS		BIT(15)
 #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_LOSC_EN		BIT(4)
 #define SUN6I_LOSC_CTRL_EXT_OSC			BIT(0)
 #define SUN6I_LOSC_CTRL_ACC_MASK		GENMASK(9, 7)
 
@@ -118,9 +111,33 @@
 #define SUN6I_YEAR_MAX				2033
 #define SUN6I_YEAR_OFF				(SUN6I_YEAR_MIN - 1900)
 
+/*
+ * There are other differences between models, including:
+ *
+ *   - number of GPIO pins that can be configured to hold a certain level
+ *   - crypto-key related registers (H5, H6)
+ *   - boot process related (super standby, secondary processor entry address)
+ *     registers (R40, H6)
+ *   - SYS power domain controls (R40)
+ *   - DCXO controls (H6)
+ *   - RC oscillator calibration (H6)
+ *
+ * These functions are not covered by this driver.
+ */
+struct sun6i_rtc_clk_data {
+	unsigned long rc_osc_rate;
+	unsigned int fixed_prescaler : 16;
+	unsigned int has_prescaler : 1;
+	unsigned int has_out_clk : 1;
+	unsigned int export_iosc : 1;
+	unsigned int has_losc_en : 1;
+	unsigned int has_auto_swt : 1;
+};
+
 struct sun6i_rtc_dev {
 	struct rtc_device *rtc;
 	struct device *dev;
+	const struct sun6i_rtc_clk_data *data;
 	void __iomem *base;
 	int irq;
 	unsigned long alarm;
@@ -139,14 +156,19 @@
 					       unsigned long parent_rate)
 {
 	struct sun6i_rtc_dev *rtc = container_of(hw, struct sun6i_rtc_dev, hw);
-	u32 val;
+	u32 val = 0;
 
 	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);
+	if (rtc->data->fixed_prescaler)
+		parent_rate /= rtc->data->fixed_prescaler;
+
+	if (rtc->data->has_prescaler) {
+		val = readl(rtc->base + SUN6I_LOSC_CLK_PRESCAL);
+		val &= GENMASK(4, 0);
+	}
 
 	return parent_rate / (val + 1);
 }
@@ -172,6 +194,10 @@
 	val &= ~SUN6I_LOSC_CTRL_EXT_OSC;
 	val |= SUN6I_LOSC_CTRL_KEY;
 	val |= index ? SUN6I_LOSC_CTRL_EXT_OSC : 0;
+	if (rtc->data->has_losc_en) {
+		val &= ~SUN6I_LOSC_CTRL_EXT_LOSC_EN;
+		val |= index ? SUN6I_LOSC_CTRL_EXT_LOSC_EN : 0;
+	}
 	writel(val, rtc->base + SUN6I_LOSC_CTRL);
 	spin_unlock_irqrestore(&rtc->lock, flags);
 
@@ -185,22 +211,26 @@
 	.set_parent	= sun6i_rtc_osc_set_parent,
 };
 
-static void __init sun6i_rtc_clk_init(struct device_node *node)
+static void __init sun6i_rtc_clk_init(struct device_node *node,
+				      const struct sun6i_rtc_clk_data *data)
 {
 	struct clk_hw_onecell_data *clk_data;
 	struct sun6i_rtc_dev *rtc;
 	struct clk_init_data init = {
 		.ops		= &sun6i_rtc_osc_ops,
+		.name		= "losc",
 	};
+	const char *iosc_name = "rtc-int-osc";
 	const char *clkout_name = "osc32k-out";
 	const char *parents[2];
+	u32 reg;
 
 	rtc = kzalloc(sizeof(*rtc), GFP_KERNEL);
 	if (!rtc)
 		return;
 
-	clk_data = kzalloc(sizeof(*clk_data) + (sizeof(*clk_data->hws) * 2),
-			   GFP_KERNEL);
+	rtc->data = data;
+	clk_data = kzalloc(struct_size(clk_data, hws, 3), GFP_KERNEL);
 	if (!clk_data) {
 		kfree(rtc);
 		return;
@@ -214,9 +244,18 @@
 		goto err;
 	}
 
+	reg = SUN6I_LOSC_CTRL_KEY;
+	if (rtc->data->has_auto_swt) {
+		/* Bypass auto-switch to int osc, on ext losc failure */
+		reg |= SUN6I_LOSC_CTRL_AUTO_SWT_BYPASS;
+		writel(reg, rtc->base + SUN6I_LOSC_CTRL);
+	}
+
 	/* Switch to the external, more precise, oscillator */
-	writel(SUN6I_LOSC_CTRL_KEY | SUN6I_LOSC_CTRL_EXT_OSC,
-	       rtc->base + SUN6I_LOSC_CTRL);
+	reg |= SUN6I_LOSC_CTRL_EXT_OSC;
+	if (rtc->data->has_losc_en)
+		reg |= SUN6I_LOSC_CTRL_EXT_LOSC_EN;
+	writel(reg, rtc->base + SUN6I_LOSC_CTRL);
 
 	/* Yes, I know, this is ugly. */
 	sun6i_rtc = rtc;
@@ -225,10 +264,15 @@
 	if (!of_get_property(node, "clocks", NULL))
 		goto err;
 
+	/* Only read IOSC name from device tree if it is exported */
+	if (rtc->data->export_iosc)
+		of_property_read_string_index(node, "clock-output-names", 2,
+					      &iosc_name);
+
 	rtc->int_osc = clk_hw_register_fixed_rate_with_accuracy(NULL,
-								"rtc-int-osc",
+								iosc_name,
 								NULL, 0,
-								667000,
+								rtc->data->rc_osc_rate,
 								300000000);
 	if (IS_ERR(rtc->int_osc)) {
 		pr_crit("Couldn't register the internal oscillator\n");
@@ -253,7 +297,7 @@
 
 	of_property_read_string_index(node, "clock-output-names", 1,
 				      &clkout_name);
-	rtc->ext_losc = clk_register_gate(NULL, clkout_name, rtc->hw.init->name,
+	rtc->ext_losc = clk_register_gate(NULL, clkout_name, init.name,
 					  0, rtc->base + SUN6I_LOSC_OUT_GATING,
 					  SUN6I_LOSC_OUT_GATING_EN_OFFSET, 0,
 					  &rtc->lock);
@@ -265,14 +309,88 @@
 	clk_data->num = 2;
 	clk_data->hws[0] = &rtc->hw;
 	clk_data->hws[1] = __clk_get_hw(rtc->ext_losc);
+	if (rtc->data->export_iosc) {
+		clk_data->hws[2] = rtc->int_osc;
+		clk_data->num = 3;
+	}
 	of_clk_add_hw_provider(node, of_clk_hw_onecell_get, clk_data);
 	return;
 
 err:
 	kfree(clk_data);
 }
-CLK_OF_DECLARE_DRIVER(sun6i_rtc_clk, "allwinner,sun6i-a31-rtc",
-		      sun6i_rtc_clk_init);
+
+static const struct sun6i_rtc_clk_data sun6i_a31_rtc_data = {
+	.rc_osc_rate = 667000, /* datasheet says 600 ~ 700 KHz */
+	.has_prescaler = 1,
+};
+
+static void __init sun6i_a31_rtc_clk_init(struct device_node *node)
+{
+	sun6i_rtc_clk_init(node, &sun6i_a31_rtc_data);
+}
+CLK_OF_DECLARE_DRIVER(sun6i_a31_rtc_clk, "allwinner,sun6i-a31-rtc",
+		      sun6i_a31_rtc_clk_init);
+
+static const struct sun6i_rtc_clk_data sun8i_a23_rtc_data = {
+	.rc_osc_rate = 667000, /* datasheet says 600 ~ 700 KHz */
+	.has_prescaler = 1,
+	.has_out_clk = 1,
+};
+
+static void __init sun8i_a23_rtc_clk_init(struct device_node *node)
+{
+	sun6i_rtc_clk_init(node, &sun8i_a23_rtc_data);
+}
+CLK_OF_DECLARE_DRIVER(sun8i_a23_rtc_clk, "allwinner,sun8i-a23-rtc",
+		      sun8i_a23_rtc_clk_init);
+
+static const struct sun6i_rtc_clk_data sun8i_h3_rtc_data = {
+	.rc_osc_rate = 16000000,
+	.fixed_prescaler = 32,
+	.has_prescaler = 1,
+	.has_out_clk = 1,
+	.export_iosc = 1,
+};
+
+static void __init sun8i_h3_rtc_clk_init(struct device_node *node)
+{
+	sun6i_rtc_clk_init(node, &sun8i_h3_rtc_data);
+}
+CLK_OF_DECLARE_DRIVER(sun8i_h3_rtc_clk, "allwinner,sun8i-h3-rtc",
+		      sun8i_h3_rtc_clk_init);
+/* As far as we are concerned, clocks for H5 are the same as H3 */
+CLK_OF_DECLARE_DRIVER(sun50i_h5_rtc_clk, "allwinner,sun50i-h5-rtc",
+		      sun8i_h3_rtc_clk_init);
+
+static const struct sun6i_rtc_clk_data sun50i_h6_rtc_data = {
+	.rc_osc_rate = 16000000,
+	.fixed_prescaler = 32,
+	.has_prescaler = 1,
+	.has_out_clk = 1,
+	.export_iosc = 1,
+	.has_losc_en = 1,
+	.has_auto_swt = 1,
+};
+
+static void __init sun50i_h6_rtc_clk_init(struct device_node *node)
+{
+	sun6i_rtc_clk_init(node, &sun50i_h6_rtc_data);
+}
+CLK_OF_DECLARE_DRIVER(sun50i_h6_rtc_clk, "allwinner,sun50i-h6-rtc",
+		      sun50i_h6_rtc_clk_init);
+
+static const struct sun6i_rtc_clk_data sun8i_v3_rtc_data = {
+	.rc_osc_rate = 32000,
+	.has_out_clk = 1,
+};
+
+static void __init sun8i_v3_rtc_clk_init(struct device_node *node)
+{
+	sun6i_rtc_clk_init(node, &sun8i_v3_rtc_data);
+}
+CLK_OF_DECLARE_DRIVER(sun8i_v3_rtc_clk, "allwinner,sun8i-v3-rtc",
+		      sun8i_v3_rtc_clk_init);
 
 static irqreturn_t sun6i_rtc_alarmirq(int irq, void *id)
 {
@@ -515,6 +633,33 @@
 	.alarm_irq_enable	= sun6i_rtc_alarm_irq_enable
 };
 
+#ifdef CONFIG_PM_SLEEP
+/* Enable IRQ wake on suspend, to wake up from RTC. */
+static int sun6i_rtc_suspend(struct device *dev)
+{
+	struct sun6i_rtc_dev *chip = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev))
+		enable_irq_wake(chip->irq);
+
+	return 0;
+}
+
+/* Disable IRQ wake on resume. */
+static int sun6i_rtc_resume(struct device *dev)
+{
+	struct sun6i_rtc_dev *chip = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev))
+		disable_irq_wake(chip->irq);
+
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(sun6i_rtc_pm_ops,
+	sun6i_rtc_suspend, sun6i_rtc_resume);
+
 static int sun6i_rtc_probe(struct platform_device *pdev)
 {
 	struct sun6i_rtc_dev *chip = sun6i_rtc;
@@ -527,10 +672,8 @@
 	chip->dev = &pdev->dev;
 
 	chip->irq = platform_get_irq(pdev, 0);
-	if (chip->irq < 0) {
-		dev_err(&pdev->dev, "No IRQ resource\n");
+	if (chip->irq < 0)
 		return chip->irq;
-	}
 
 	ret = devm_request_irq(&pdev->dev, chip->irq, sun6i_rtc_alarmirq,
 			       0, dev_name(&pdev->dev), chip);
@@ -567,6 +710,8 @@
 
 	clk_prepare_enable(chip->losc);
 
+	device_init_wakeup(&pdev->dev, 1);
+
 	chip->rtc = devm_rtc_device_register(&pdev->dev, "rtc-sun6i",
 					     &sun6i_rtc_ops, THIS_MODULE);
 	if (IS_ERR(chip->rtc)) {
@@ -579,8 +724,20 @@
 	return 0;
 }
 
+/*
+ * As far as RTC functionality goes, all models are the same. The
+ * datasheets claim that different models have different number of
+ * registers available for non-volatile storage, but experiments show
+ * that all SoCs have 16 registers available for this purpose.
+ */
 static const struct of_device_id sun6i_rtc_dt_ids[] = {
 	{ .compatible = "allwinner,sun6i-a31-rtc" },
+	{ .compatible = "allwinner,sun8i-a23-rtc" },
+	{ .compatible = "allwinner,sun8i-h3-rtc" },
+	{ .compatible = "allwinner,sun8i-r40-rtc" },
+	{ .compatible = "allwinner,sun8i-v3-rtc" },
+	{ .compatible = "allwinner,sun50i-h5-rtc" },
+	{ .compatible = "allwinner,sun50i-h6-rtc" },
 	{ /* sentinel */ },
 };
 MODULE_DEVICE_TABLE(of, sun6i_rtc_dt_ids);
@@ -590,6 +747,7 @@
 	.driver		= {
 		.name		= "sun6i-rtc",
 		.of_match_table = sun6i_rtc_dt_ids,
+		.pm = &sun6i_rtc_pm_ops,
 	},
 };
 builtin_platform_driver(sun6i_rtc_driver);