From: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> stable inclusion from linux-4.19.207 commit eb7ff81efcc5bd7123a22f66864bc7e88afdd739 -------------------------------- commit 54784ffa5b267f57161eb8fbb811499f22a0a0bf upstream. Reading status register can fail in the interrupt handler. In such case, the regmap_read() will not store anything useful under passed 'val' variable and random stack value will be used to determine type of interrupt. Handle the regmap_read() failure to avoid handling interrupt type and triggering changed power supply event based on random stack value. Fixes: 39e7213edc4f ("max17042_battery: Support regmap to access device's registers") Cc: <stable@vger.kernel.org> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- drivers/power/supply/max17042_battery.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/power/supply/max17042_battery.c b/drivers/power/supply/max17042_battery.c index 8618dbb723926..a1518eb6f6c0d 100644 --- a/drivers/power/supply/max17042_battery.c +++ b/drivers/power/supply/max17042_battery.c @@ -856,8 +856,12 @@ static irqreturn_t max17042_thread_handler(int id, void *dev) { struct max17042_chip *chip = dev; u32 val; + int ret; + + ret = regmap_read(chip->regmap, MAX17042_STATUS, &val); + if (ret) + return IRQ_HANDLED; - regmap_read(chip->regmap, MAX17042_STATUS, &val); if ((val & STATUS_INTR_SOCMIN_BIT) || (val & STATUS_INTR_SOCMAX_BIT)) { dev_info(&chip->client->dev, "SOC threshold INTR\n"); -- 2.25.1