drivers/rtc/rtc-tps6586x.c

Source file repositories/reference/linux-study-clean/drivers/rtc/rtc-tps6586x.c

File Facts

System
Linux kernel
Corpus path
drivers/rtc/rtc-tps6586x.c
Extension
.c
Size
7924 bytes
Lines
328
Domain
Driver Families
Bucket
drivers/rtc
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 tps6586x_rtc {
	struct device		*dev;
	struct rtc_device	*rtc;
	int			irq;
	bool			irq_en;
};

static inline struct device *to_tps6586x_dev(struct device *dev)
{
	return dev->parent;
}

static int tps6586x_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
	struct device *tps_dev = to_tps6586x_dev(dev);
	unsigned long long ticks = 0;
	time64_t seconds;
	u8 buff[6];
	int ret;
	int i;

	ret = tps6586x_reads(tps_dev, RTC_COUNT4_DUMMYREAD, sizeof(buff), buff);
	if (ret < 0) {
		dev_err(dev, "read counter failed with err %d\n", ret);
		return ret;
	}

	for (i = 1; i < sizeof(buff); i++) {
		ticks <<= 8;
		ticks |= buff[i];
	}

	seconds = ticks >> 10;
	rtc_time64_to_tm(seconds, tm);

	return 0;
}

static int tps6586x_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
	struct device *tps_dev = to_tps6586x_dev(dev);
	unsigned long long ticks;
	time64_t seconds;
	u8 buff[5];
	int ret;

	seconds = rtc_tm_to_time64(tm);

	ticks = (unsigned long long)seconds << 10;
	buff[0] = (ticks >> 32) & 0xff;
	buff[1] = (ticks >> 24) & 0xff;
	buff[2] = (ticks >> 16) & 0xff;
	buff[3] = (ticks >> 8) & 0xff;
	buff[4] = ticks & 0xff;

	/* Disable RTC before changing time */
	ret = tps6586x_clr_bits(tps_dev, RTC_CTRL, RTC_ENABLE);
	if (ret < 0) {
		dev_err(dev, "failed to clear RTC_ENABLE\n");
		return ret;
	}

	ret = tps6586x_writes(tps_dev, RTC_COUNT4, sizeof(buff), buff);
	if (ret < 0) {
		dev_err(dev, "failed to program new time\n");
		return ret;
	}

	/* Enable RTC */
	ret = tps6586x_set_bits(tps_dev, RTC_CTRL, RTC_ENABLE);
	if (ret < 0) {
		dev_err(dev, "failed to set RTC_ENABLE\n");
		return ret;
	}
	return 0;
}

static int tps6586x_rtc_alarm_irq_enable(struct device *dev,
			 unsigned int enabled)
{
	struct tps6586x_rtc *rtc = dev_get_drvdata(dev);

	if (enabled && !rtc->irq_en) {
		enable_irq(rtc->irq);
		rtc->irq_en = true;
	} else if (!enabled && rtc->irq_en)  {
		disable_irq(rtc->irq);
		rtc->irq_en = false;
	}
	return 0;

Annotation

Implementation Notes