drivers/rtc/rtc-rx8010.c

Source file repositories/reference/linux-study-clean/drivers/rtc/rtc-rx8010.c

File Facts

System
Linux kernel
Corpus path
drivers/rtc/rtc-rx8010.c
Extension
.c
Size
10568 bytes
Lines
435
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 rx8010_data {
	struct regmap *regs;
	struct rtc_device *rtc;
	u8 ctrlreg;
};

static irqreturn_t rx8010_irq_1_handler(int irq, void *dev_id)
{
	struct i2c_client *client = dev_id;
	struct rx8010_data *rx8010 = i2c_get_clientdata(client);
	int flagreg, err;

	rtc_lock(rx8010->rtc);

	err = regmap_read(rx8010->regs, RX8010_FLAG, &flagreg);
	if (err) {
		rtc_unlock(rx8010->rtc);
		return IRQ_NONE;
	}

	if (flagreg & RX8010_FLAG_VLF)
		dev_warn(&client->dev, "Frequency stop detected\n");

	if (flagreg & RX8010_FLAG_TF) {
		flagreg &= ~RX8010_FLAG_TF;
		rtc_update_irq(rx8010->rtc, 1, RTC_PF | RTC_IRQF);
	}

	if (flagreg & RX8010_FLAG_AF) {
		flagreg &= ~RX8010_FLAG_AF;
		rtc_update_irq(rx8010->rtc, 1, RTC_AF | RTC_IRQF);
	}

	if (flagreg & RX8010_FLAG_UF) {
		flagreg &= ~RX8010_FLAG_UF;
		rtc_update_irq(rx8010->rtc, 1, RTC_UF | RTC_IRQF);
	}

	err = regmap_write(rx8010->regs, RX8010_FLAG, flagreg);
	rtc_unlock(rx8010->rtc);
	return err ? IRQ_NONE : IRQ_HANDLED;
}

static int rx8010_get_time(struct device *dev, struct rtc_time *dt)
{
	struct rx8010_data *rx8010 = dev_get_drvdata(dev);
	u8 date[RX8010_YEAR - RX8010_SEC + 1];
	int flagreg, err;

	err = regmap_read(rx8010->regs, RX8010_FLAG, &flagreg);
	if (err)
		return err;

	if (flagreg & RX8010_FLAG_VLF) {
		dev_warn(dev, "Frequency stop detected\n");
		return -EINVAL;
	}

	err = regmap_bulk_read(rx8010->regs, RX8010_SEC, date, sizeof(date));
	if (err)
		return err;

	dt->tm_sec = bcd2bin(date[RX8010_SEC - RX8010_SEC] & 0x7f);
	dt->tm_min = bcd2bin(date[RX8010_MIN - RX8010_SEC] & 0x7f);
	dt->tm_hour = bcd2bin(date[RX8010_HOUR - RX8010_SEC] & 0x3f);
	dt->tm_mday = bcd2bin(date[RX8010_MDAY - RX8010_SEC] & 0x3f);
	dt->tm_mon = bcd2bin(date[RX8010_MONTH - RX8010_SEC] & 0x1f) - 1;
	dt->tm_year = bcd2bin(date[RX8010_YEAR - RX8010_SEC]) + 100;
	dt->tm_wday = ffs(date[RX8010_WDAY - RX8010_SEC] & 0x7f);

	return 0;
}

static int rx8010_set_time(struct device *dev, struct rtc_time *dt)
{
	struct rx8010_data *rx8010 = dev_get_drvdata(dev);
	u8 date[RX8010_YEAR - RX8010_SEC + 1];
	int err;

	/* set STOP bit before changing clock/calendar */
	err = regmap_set_bits(rx8010->regs, RX8010_CTRL, RX8010_CTRL_STOP);
	if (err)
		return err;

	date[RX8010_SEC - RX8010_SEC] = bin2bcd(dt->tm_sec);
	date[RX8010_MIN - RX8010_SEC] = bin2bcd(dt->tm_min);
	date[RX8010_HOUR - RX8010_SEC] = bin2bcd(dt->tm_hour);
	date[RX8010_MDAY - RX8010_SEC] = bin2bcd(dt->tm_mday);
	date[RX8010_MONTH - RX8010_SEC] = bin2bcd(dt->tm_mon + 1);
	date[RX8010_YEAR - RX8010_SEC] = bin2bcd(dt->tm_year - 100);

Annotation

Implementation Notes