drivers/watchdog/rtd119x_wdt.c

Source file repositories/reference/linux-study-clean/drivers/watchdog/rtd119x_wdt.c

File Facts

System
Linux kernel
Corpus path
drivers/watchdog/rtd119x_wdt.c
Extension
.c
Size
3455 bytes
Lines
140
Domain
Driver Families
Bucket
drivers/watchdog
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

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;

Annotation

Implementation Notes