diff mbox series

[1/3] power: supply: max17042: handle fails of reading status register

Message ID 20210816082716.21193-1-krzysztof.kozlowski@canonical.com
State Accepted
Commit 54784ffa5b267f57161eb8fbb811499f22a0a0bf
Headers show
Series [1/3] power: supply: max17042: handle fails of reading status register | expand

Commit Message

Krzysztof Kozlowski Aug. 16, 2021, 8:27 a.m. UTC
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>
---
 drivers/power/supply/max17042_battery.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

Comments

Sebastian Reichel Aug. 16, 2021, 11:08 a.m. UTC | #1
Hi,

On Mon, Aug 16, 2021 at 10:42:01AM +0200, Hans de Goede wrote:
> Hi,
> 
> On 8/16/21 10:27 AM, Krzysztof Kozlowski wrote:
> > 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>
> 
> Thanks, the entire series looks good to me:
> 
> Reviewed-by: Hans de Goede <hdegoede@redhat.com>
> 
> For the series.

Thanks, series queued.

-- Sebastian

> 
> Regards,
> 
> Hans
> 
> > ---
> >  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 ce2041b30a06..858ae97600d4 100644
> > --- a/drivers/power/supply/max17042_battery.c
> > +++ b/drivers/power/supply/max17042_battery.c
> > @@ -869,8 +869,12 @@ 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");
> > 
>
diff mbox series

Patch

diff --git a/drivers/power/supply/max17042_battery.c b/drivers/power/supply/max17042_battery.c
index ce2041b30a06..858ae97600d4 100644
--- a/drivers/power/supply/max17042_battery.c
+++ b/drivers/power/supply/max17042_battery.c
@@ -869,8 +869,12 @@  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");