This is a note to let you know that I've just added the patch titled
rtc: pm8xxx: fix set-alarm race
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
rtc-pm8xxx-fix-set-alarm-race.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From c88db0eff9722fc2b6c4d172a50471d20e08ecc6 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan+linaro@xxxxxxxxxx>
Date: Thu, 2 Feb 2023 16:54:27 +0100
Subject: rtc: pm8xxx: fix set-alarm race
From: Johan Hovold <johan+linaro@xxxxxxxxxx>
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@xxxxxxxxxxxxxxx # 3.1
Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx>
Reviewed-by: David Collins <quic_collinsd@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230202155448.6715-2-johan+linaro@xxxxxxxxxx
Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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
@@ -221,7 +221,6 @@ 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;
@@ -233,6 +232,11 @@ 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,
@@ -242,19 +246,11 @@ 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:m:s=%ptRt, y-m-d=%ptRdr\n",
Patches currently in stable-queue which might be from johan+linaro@xxxxxxxxxx are
queue-6.1/rtc-pm8xxx-fix-set-alarm-race.patch
queue-6.1/pci-qcom-fix-host-init-error-handling.patch
queue-6.1/drm-panel-edp-fix-name-for-ivo-product-id-854b.patch
queue-6.1/arm64-dts-qcom-sc8280xp-sa8540p-add-pcie2-4-nodes.patch
queue-6.1/arm64-dts-qcom-sc8280xp-correct-spmi-bus-address-cel.patch
