From: Johan Hovold johan+linaro@kernel.org
commit c88db0eff9722fc2b6c4d172a50471d20e08ecc6 upstream.
Make sure to disable the alarm before updating the four alarm time registers to avoid spurious alarms during the update.
Note that the disable needs to be done outside of the ctrl_reg_lock section to prevent a racing alarm interrupt from disabling the newly set alarm when the lock is released.
Fixes: 9a9a54ad7aa2 ("drivers/rtc: add support for Qualcomm PMIC8xxx RTC") Cc: stable@vger.kernel.org # 3.1 Signed-off-by: Johan Hovold johan+linaro@kernel.org Reviewed-by: David Collins quic_collinsd@quicinc.com Link: https://lore.kernel.org/r/20230202155448.6715-2-johan+linaro@kernel.org Signed-off-by: Alexandre Belloni alexandre.belloni@bootlin.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/rtc/rtc-pm8xxx.c | 24 ++++++++++-------------- 1 file changed, 10 insertions(+), 14 deletions(-)
--- a/drivers/rtc/rtc-pm8xxx.c +++ b/drivers/rtc/rtc-pm8xxx.c @@ -235,7 +235,6 @@ static int pm8xxx_rtc_set_alarm(struct d { int rc, i; u8 value[NUM_8_BIT_RTC_REGS]; - unsigned int ctrl_reg; unsigned long secs, irq_flags; struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev); const struct pm8xxx_rtc_regs *regs = rtc_dd->regs; @@ -247,6 +246,11 @@ static int pm8xxx_rtc_set_alarm(struct d secs >>= 8; }
+ rc = regmap_update_bits(rtc_dd->regmap, regs->alarm_ctrl, + regs->alarm_en, 0); + if (rc) + return rc; + spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
rc = regmap_bulk_write(rtc_dd->regmap, regs->alarm_rw, value, @@ -256,19 +260,11 @@ static int pm8xxx_rtc_set_alarm(struct d goto rtc_rw_fail; }
- rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg); - if (rc) - goto rtc_rw_fail; - - if (alarm->enabled) - ctrl_reg |= regs->alarm_en; - else - 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; + if (alarm->enabled) { + rc = regmap_update_bits(rtc_dd->regmap, regs->alarm_ctrl, + regs->alarm_en, regs->alarm_en); + if (rc) + goto rtc_rw_fail; }
dev_dbg(dev, "Alarm Set for h:r:s=%d:%d:%d, d/m/y=%d/%d/%d\n",