static int pm8xxx_rtc_set_time()

in rtc-pm8xxx.c [76:173]

• 77 lines of code
• 16 McCabe index (conditional complexity)

static int pm8xxx_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
	int rc, i;
	unsigned long secs, irq_flags;
	u8 value[NUM_8_BIT_RTC_REGS], alarm_enabled = 0, rtc_disabled = 0;
	unsigned int ctrl_reg, rtc_ctrl_reg;
	struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
	const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;

	if (!rtc_dd->allow_set_time)
		return -EACCES;

	secs = rtc_tm_to_time64(tm);

	dev_dbg(dev, "Seconds value to be written to RTC = %lu\n", secs);

	for (i = 0; i < NUM_8_BIT_RTC_REGS; i++) {
		value[i] = secs & 0xFF;
		secs >>= 8;
	}

	spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);

	rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg);
	if (rc)
		goto rtc_rw_fail;

	if (ctrl_reg & regs->alarm_en) {
		alarm_enabled = 1;
		ctrl_reg &= ~regs->alarm_en;
		rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
		if (rc) {
			dev_err(dev, "Write to RTC Alarm control register failed\n");
			goto rtc_rw_fail;
		}
	}

	/* Disable RTC H/w before writing on RTC register */
	rc = regmap_read(rtc_dd->regmap, regs->ctrl, &rtc_ctrl_reg);
	if (rc)
		goto rtc_rw_fail;

	if (rtc_ctrl_reg & PM8xxx_RTC_ENABLE) {
		rtc_disabled = 1;
		rtc_ctrl_reg &= ~PM8xxx_RTC_ENABLE;
		rc = regmap_write(rtc_dd->regmap, regs->ctrl, rtc_ctrl_reg);
		if (rc) {
			dev_err(dev, "Write to RTC control register failed\n");
			goto rtc_rw_fail;
		}
	}

	/* Write 0 to Byte[0] */
	rc = regmap_write(rtc_dd->regmap, regs->write, 0);
	if (rc) {
		dev_err(dev, "Write to RTC write data register failed\n");
		goto rtc_rw_fail;
	}

	/* Write Byte[1], Byte[2], Byte[3] */
	rc = regmap_bulk_write(rtc_dd->regmap, regs->write + 1,
			       &value[1], sizeof(value) - 1);
	if (rc) {
		dev_err(dev, "Write to RTC write data register failed\n");
		goto rtc_rw_fail;
	}

	/* Write Byte[0] */
	rc = regmap_write(rtc_dd->regmap, regs->write, value[0]);
	if (rc) {
		dev_err(dev, "Write to RTC write data register failed\n");
		goto rtc_rw_fail;
	}

	/* Enable RTC H/w after writing on RTC register */
	if (rtc_disabled) {
		rtc_ctrl_reg |= PM8xxx_RTC_ENABLE;
		rc = regmap_write(rtc_dd->regmap, regs->ctrl, rtc_ctrl_reg);
		if (rc) {
			dev_err(dev, "Write to RTC control register failed\n");
			goto rtc_rw_fail;
		}
	}

	if (alarm_enabled) {
		ctrl_reg |= regs->alarm_en;
		rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
		if (rc) {
			dev_err(dev, "Write to RTC Alarm control register failed\n");
			goto rtc_rw_fail;
		}
	}

rtc_rw_fail:
	spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);

	return rc;
}