All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH] hwmon: (ina3221) Clamp shunt resistor value from DT
@ 2018-10-08 20:05 Nicolin Chen
  2018-10-08 20:24 ` Guenter Roeck
  0 siblings, 1 reply; 2+ messages in thread
From: Nicolin Chen @ 2018-10-08 20:05 UTC (permalink / raw)
  To: jdelvare, linux; +Cc: afd, linux-hwmon, linux-kernel

The input->shunt_resistor is int type while the value from DT is
unsigned int. Meanwhile, a divide-by-zero error would happen if
the value is 0. So this patch just simply clamps the value.

Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
---
 drivers/hwmon/ina3221.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/hwmon/ina3221.c b/drivers/hwmon/ina3221.c
index c3a497aed345..ce8f0a8c4982 100644
--- a/drivers/hwmon/ina3221.c
+++ b/drivers/hwmon/ina3221.c
@@ -536,8 +536,10 @@ static int ina3221_probe_child_from_dt(struct device *dev,
 	of_property_read_string(child, "label", &input->label);
 
 	/* Overwrite default shunt resistor value optionally */
-	if (!of_property_read_u32(child, "shunt-resistor-micro-ohms", &val))
+	if (!of_property_read_u32(child, "shunt-resistor-micro-ohms", &val)) {
+		val = clamp_val(val, 1, INT_MAX);
 		input->shunt_resistor = val;
+	}
 
 	return 0;
 }
-- 
2.17.1

^ permalink raw reply related	[flat|nested] 2+ messages in thread

* Re: [PATCH] hwmon: (ina3221) Clamp shunt resistor value from DT
  2018-10-08 20:05 [PATCH] hwmon: (ina3221) Clamp shunt resistor value from DT Nicolin Chen
@ 2018-10-08 20:24 ` Guenter Roeck
  0 siblings, 0 replies; 2+ messages in thread
From: Guenter Roeck @ 2018-10-08 20:24 UTC (permalink / raw)
  To: Nicolin Chen; +Cc: jdelvare, afd, linux-hwmon, linux-kernel

On Mon, Oct 08, 2018 at 01:05:37PM -0700, Nicolin Chen wrote:
> The input->shunt_resistor is int type while the value from DT is
> unsigned int. Meanwhile, a divide-by-zero error would happen if
> the value is 0. So this patch just simply clamps the value.
> 

I think it would be better to validate the numbers here instead of 
silently accepting bad values, and return -EINVAL if the property value
is bad.

Thanks,
Guenter

> Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
> ---
>  drivers/hwmon/ina3221.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/hwmon/ina3221.c b/drivers/hwmon/ina3221.c
> index c3a497aed345..ce8f0a8c4982 100644
> --- a/drivers/hwmon/ina3221.c
> +++ b/drivers/hwmon/ina3221.c
> @@ -536,8 +536,10 @@ static int ina3221_probe_child_from_dt(struct device *dev,
>  	of_property_read_string(child, "label", &input->label);
>  
>  	/* Overwrite default shunt resistor value optionally */
> -	if (!of_property_read_u32(child, "shunt-resistor-micro-ohms", &val))
> +	if (!of_property_read_u32(child, "shunt-resistor-micro-ohms", &val)) {
> +		val = clamp_val(val, 1, INT_MAX);
>  		input->shunt_resistor = val;
> +	}
>  
>  	return 0;
>  }
> -- 
> 2.17.1
> 

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2018-10-09  3:37 UTC | newest]

Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-10-08 20:05 [PATCH] hwmon: (ina3221) Clamp shunt resistor value from DT Nicolin Chen
2018-10-08 20:24 ` Guenter Roeck

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.