On Thu, 27 Aug 2020 10:44:01 +0530
Viresh Kumar <viresh.ku...@linaro.org> wrote:
> On 27-08-20, 12:03, Yue Hu wrote:
> > Hi Daniel,
> >
> > Now, i'm just focus on removing the kernel warning based on current code
> > logic.
> > Commit 8ea229511e06 (thermal: Add cooling device's statistics in sysfs)
> > added
> > the thermal statistics by viresh and viresh gived the patch an
> > acknowledgement
> > in anther mail thread.
> >
> > Hi viresh,
> >
> > Could you review the patch again about the question above?
>
> Yeah, I Acked it but the questions raised by Daniel are very valid and must be
> answered.
Yes, sure.
>
> I understand that you only cared about fixing the warning, but maybe we need
> to
> fix the driver and the warning will go away by itself. If you don't want to do
> it, then someone who is responsible for the driver should do it.
Yes, maybe the patch is not totally correct. maybe the driver has issue. Let's
check the driver firstly.
>
> Was it the acpi_video.c driver that you got the warning from ? I have added
> Rafael to the email in case that driver needs getting fixed.
>
Currenly, drivers/video/backlight does not call
thermal_of_cooling_device_register()
to register thermal cooling device. The issue happened in msm-4.19 kernel for
QCOM/Android platform. Backlight in msm-4.19 kernel will register thermal
cooling
device as below:
+static int bd_cdev_get_max_brightness(struct thermal_cooling_device *cdev,
+ unsigned long *state)
+{
+ struct backlight_device *bd = (struct backlight_device *)cdev->devdata;
+
+ *state = bd->props.max_brightness;
+
+ return 0;
+}
+static struct thermal_cooling_device_ops bd_cdev_ops = {
+ .get_max_state = bd_cdev_get_max_brightness,
+static void backlight_cdev_register(struct device *parent,
+ struct backlight_device *bd)
+{
+ if (of_find_property(parent->of_node, "#cooling-cells", NULL)) {
+ bd->cdev = thermal_of_cooling_device_register(parent->of_node,
+ (char *)dev_name(&bd->dev), bd, &bd_cdev_ops);
And the bd->props.max_brightness is getting from video/backlight/qcom-wled.c.
Maybe
the driver should not assign 1024 to states/max_brightness. I'm not sure about
it.
So i consider to change memory allocation methord. That's the origin of the
patch.
Thank you.
