1 files changed, 139 insertions, 0 deletions
diff --git a/drivers/watchdog/rtd119x_wdt.c b/drivers/watchdog/rtd119x_wdt.c
new file mode 100644
index 000000000..984905695
--- /dev/null
+++ b/drivers/watchdog/rtd119x_wdt.c
@@ -0,0 +1,139 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Realtek RTD129x watchdog
+ *
+ * Copyright (c) 2017 Andreas Färber
+ *
+ */
+
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/watchdog.h>
+
+#define RTD119X_TCWCR		0x0
+#define RTD119X_TCWTR		0x4
+#define RTD119X_TCWOV		0xc
+
+#define RTD119X_TCWCR_WDEN_DISABLED		0xa5
+#define RTD119X_TCWCR_WDEN_ENABLED		0xff
+#define RTD119X_TCWCR_WDEN_MASK			0xff
+
+#define RTD119X_TCWTR_WDCLR			BIT(0)
+
+struct rtd119x_watchdog_device {
+	struct watchdog_device wdt_dev;
+	void __iomem *base;
+	struct clk *clk;
+};
+
+static int rtd119x_wdt_start(struct watchdog_device *wdev)
+{
+	struct rtd119x_watchdog_device *data = watchdog_get_drvdata(wdev);
+	u32 val;
+
+	val = readl_relaxed(data->base + RTD119X_TCWCR);
+	val &= ~RTD119X_TCWCR_WDEN_MASK;
+	val |= RTD119X_TCWCR_WDEN_ENABLED;
+	writel(val, data->base + RTD119X_TCWCR);
+
+	return 0;
+}
+
+static int rtd119x_wdt_stop(struct watchdog_device *wdev)
+{
+	struct rtd119x_watchdog_device *data = watchdog_get_drvdata(wdev);
+	u32 val;
+
+	val = readl_relaxed(data->base + RTD119X_TCWCR);
+	val &= ~RTD119X_TCWCR_WDEN_MASK;
+	val |= RTD119X_TCWCR_WDEN_DISABLED;
+	writel(val, data->base + RTD119X_TCWCR);
+
+	return 0;
+}
+
+static int rtd119x_wdt_ping(struct watchdog_device *wdev)
+{
+	struct rtd119x_watchdog_device *data = watchdog_get_drvdata(wdev);
+
+	writel_relaxed(RTD119X_TCWTR_WDCLR, data->base + RTD119X_TCWTR);
+
+	return rtd119x_wdt_start(wdev);
+}
+
+static int rtd119x_wdt_set_timeout(struct watchdog_device *wdev, unsigned int val)
+{
+	struct rtd119x_watchdog_device *data = watchdog_get_drvdata(wdev);
+
+	writel(val * clk_get_rate(data->clk), data->base + RTD119X_TCWOV);
+
+	data->wdt_dev.timeout = val;
+
+	return 0;
+}
+
+static const struct watchdog_ops rtd119x_wdt_ops = {
+	.owner = THIS_MODULE,
+	.start		= rtd119x_wdt_start,
+	.stop		= rtd119x_wdt_stop,
+	.ping		= rtd119x_wdt_ping,
+	.set_timeout	= rtd119x_wdt_set_timeout,
+};
+
+static const struct watchdog_info rtd119x_wdt_info = {
+	.identity = "rtd119x-wdt",
+	.options = 0,
+};
+
+static const struct of_device_id rtd119x_wdt_dt_ids[] = {
+	 { .compatible = "realtek,rtd1295-watchdog" },
+	 { }
+};
+
+static int rtd119x_wdt_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct rtd119x_watchdog_device *data;
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(data->base))
+		return PTR_ERR(data->base);
+
+	data->clk = devm_clk_get_enabled(dev, NULL);
+	if (IS_ERR(data->clk))
+		return PTR_ERR(data->clk);
+
+	data->wdt_dev.info = &rtd119x_wdt_info;
+	data->wdt_dev.ops = &rtd119x_wdt_ops;
+	data->wdt_dev.timeout = 120;
+	data->wdt_dev.max_timeout = 0xffffffff / clk_get_rate(data->clk);
+	data->wdt_dev.min_timeout = 1;
+	data->wdt_dev.parent = dev;
+
+	watchdog_stop_on_reboot(&data->wdt_dev);
+	watchdog_set_drvdata(&data->wdt_dev, data);
+	platform_set_drvdata(pdev, data);
+
+	writel_relaxed(RTD119X_TCWTR_WDCLR, data->base + RTD119X_TCWTR);
+	rtd119x_wdt_set_timeout(&data->wdt_dev, data->wdt_dev.timeout);
+	rtd119x_wdt_stop(&data->wdt_dev);
+
+	return devm_watchdog_register_device(dev, &data->wdt_dev);
+}
+
+static struct platform_driver rtd119x_wdt_driver = {
+	.probe = rtd119x_wdt_probe,
+	.driver = {
+		.name = "rtd1295-watchdog",
+		.of_match_table	= rtd119x_wdt_dt_ids,
+	},
+};
+builtin_platform_driver(rtd119x_wdt_driver);