drivers/watchdog/intel_oc_wdt.c

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

File Facts

System
Linux kernel
Corpus path
drivers/watchdog/intel_oc_wdt.c
Extension
.c
Size
5856 bytes
Lines
234
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 intel_oc_wdt {
	struct watchdog_device wdd;
	struct resource *ctrl_res;
	struct watchdog_info info;
	bool locked;
};

static int heartbeat;
module_param(heartbeat, uint, 0);
MODULE_PARM_DESC(heartbeat, "Watchdog heartbeats in seconds. (default="
		 __MODULE_STRING(WDT_HEARTBEAT) ")");

static bool nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
		 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");

static int intel_oc_wdt_start(struct watchdog_device *wdd)
{
	struct intel_oc_wdt *oc_wdt = watchdog_get_drvdata(wdd);

	if (oc_wdt->locked)
		return 0;

	outl(inl(INTEL_OC_WDT_CTRL_REG(oc_wdt)) | INTEL_OC_WDT_EN,
	     INTEL_OC_WDT_CTRL_REG(oc_wdt));

	return 0;
}

static int intel_oc_wdt_stop(struct watchdog_device *wdd)
{
	struct intel_oc_wdt *oc_wdt = watchdog_get_drvdata(wdd);

	outl(inl(INTEL_OC_WDT_CTRL_REG(oc_wdt)) & ~INTEL_OC_WDT_EN,
	     INTEL_OC_WDT_CTRL_REG(oc_wdt));

	return 0;
}

static int intel_oc_wdt_ping(struct watchdog_device *wdd)
{
	struct intel_oc_wdt *oc_wdt = watchdog_get_drvdata(wdd);

	outl(inl(INTEL_OC_WDT_CTRL_REG(oc_wdt)) | INTEL_OC_WDT_RLD,
	     INTEL_OC_WDT_CTRL_REG(oc_wdt));

	return 0;
}

static int intel_oc_wdt_set_timeout(struct watchdog_device *wdd,
				    unsigned int t)
{
	struct intel_oc_wdt *oc_wdt = watchdog_get_drvdata(wdd);

	outl((inl(INTEL_OC_WDT_CTRL_REG(oc_wdt)) & ~INTEL_OC_WDT_TOV) | (t - 1),
	     INTEL_OC_WDT_CTRL_REG(oc_wdt));

	wdd->timeout = t;

	return 0;
}

static const struct watchdog_info intel_oc_wdt_info = {
	.options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
	.identity = DRV_NAME,
};

static const struct watchdog_ops intel_oc_wdt_ops = {
	.owner = THIS_MODULE,
	.start = intel_oc_wdt_start,
	.stop = intel_oc_wdt_stop,
	.ping = intel_oc_wdt_ping,
	.set_timeout = intel_oc_wdt_set_timeout,
};

static int intel_oc_wdt_setup(struct intel_oc_wdt *oc_wdt)
{
	unsigned long val;

	val = inl(INTEL_OC_WDT_CTRL_REG(oc_wdt));

	if (val & INTEL_OC_WDT_STS_BITS)
		oc_wdt->wdd.bootstatus |= WDIOF_CARDRESET;

	oc_wdt->locked = !!(val & INTEL_OC_WDT_CTL_LCK);

	if (val & INTEL_OC_WDT_EN) {
		/*
		 * No need to issue a ping here to "commit" the new timeout

Annotation

Implementation Notes