| Message ID | 1431399857-13943-2-git-send-email-edubezval@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Eduardo Valentin |
| Headers | show |
Copying Narendran. On Mon, May 11, 2015 at 08:04:16PM -0700, Eduardo Valentin wrote: > It is common to have a linear extrapolation from > the current sensor readings and the actual temperature > value. This is specially the case when the sensor > is in use to extrapolate hotspots. > > This patch adds slope and offset constants for > single sensor linear extrapolation equation. Because > the same sensor can be use in different locations, > from board to board, these constants are added > as part of thermal_zone_params. > > The constants are available through sysfs. > > It is up to the device driver to determine > the usage of these values. > > Signed-off-by: Eduardo Valentin <edubezval@gmail.com> > --- > Documentation/thermal/sysfs-api.txt | 16 ++++++++++++++++ > drivers/thermal/thermal_core.c | 4 ++++ > include/linux/thermal.h | 11 +++++++++++ > 3 files changed, 31 insertions(+) > > diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt > index 7d44d7f..c1f6864 100644 > --- a/Documentation/thermal/sysfs-api.txt > +++ b/Documentation/thermal/sysfs-api.txt > @@ -190,6 +190,8 @@ Thermal zone device sys I/F, created once it's registered: > |---k_i: PID's integral term in the power allocator gov > |---k_d: PID's derivative term in the power allocator > |---integral_cutoff: Offset above which errors are accumulated > + |---slope: Slope constant applied as linear extrapolation > + |---offset: Offset constant applied as linear extrapolation > > Thermal cooling device sys I/F, created once it's registered: > /sys/class/thermal/cooling_device[0-*]: > @@ -359,6 +361,20 @@ integral_cutoff > Documentation/thermal/power_allocator.txt > RW, Optional > > +slope > + The slope constant used in a linear extrapolation model > + to determine a hotspot temperature based off the sensor's > + raw readings. It is up to the device driver to determine > + the usage of these values. > + RW, Optional > + > +offset > + The offset constant used in a linear extrapolation model > + to determine a hotspot temperature based off the sensor's > + raw readings. It is up to the device driver to determine > + the usage of these values. > + RW, Optional > + > ***************************** > * Cooling device attributes * > ***************************** > diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c > index 962de18..04659bf 100644 > --- a/drivers/thermal/thermal_core.c > +++ b/drivers/thermal/thermal_core.c > @@ -944,6 +944,8 @@ create_s32_tzp_attr(k_pu); > create_s32_tzp_attr(k_i); > create_s32_tzp_attr(k_d); > create_s32_tzp_attr(integral_cutoff); > +create_s32_tzp_attr(slope); > +create_s32_tzp_attr(offset); > #undef create_s32_tzp_attr > > static struct device_attribute *dev_tzp_attrs[] = { > @@ -953,6 +955,8 @@ static struct device_attribute *dev_tzp_attrs[] = { > &dev_attr_k_i, > &dev_attr_k_d, > &dev_attr_integral_cutoff, > + &dev_attr_slope, > + &dev_attr_offset, > }; > > static int create_tzp_attrs(struct device *dev) > diff --git a/include/linux/thermal.h b/include/linux/thermal.h > index 6bbe11c..037e9df 100644 > --- a/include/linux/thermal.h > +++ b/include/linux/thermal.h > @@ -302,6 +302,17 @@ struct thermal_zone_params { > > /* threshold below which the error is no longer accumulated */ > s32 integral_cutoff; > + > + /* > + * @slope: slope of a linear temperature adjustment curve. > + * Used by thermal zone drivers. > + */ > + int slope; > + /* > + * @offset: offset of a linear temperature adjustment curve. > + * Used by thermal zone drivers (default 0). > + */ > + int offset; > }; > > struct thermal_genl_event { > -- > 2.3.4 >
diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt index 7d44d7f..c1f6864 100644 --- a/Documentation/thermal/sysfs-api.txt +++ b/Documentation/thermal/sysfs-api.txt @@ -190,6 +190,8 @@ Thermal zone device sys I/F, created once it's registered: |---k_i: PID's integral term in the power allocator gov |---k_d: PID's derivative term in the power allocator |---integral_cutoff: Offset above which errors are accumulated + |---slope: Slope constant applied as linear extrapolation + |---offset: Offset constant applied as linear extrapolation Thermal cooling device sys I/F, created once it's registered: /sys/class/thermal/cooling_device[0-*]: @@ -359,6 +361,20 @@ integral_cutoff Documentation/thermal/power_allocator.txt RW, Optional +slope + The slope constant used in a linear extrapolation model + to determine a hotspot temperature based off the sensor's + raw readings. It is up to the device driver to determine + the usage of these values. + RW, Optional + +offset + The offset constant used in a linear extrapolation model + to determine a hotspot temperature based off the sensor's + raw readings. It is up to the device driver to determine + the usage of these values. + RW, Optional + ***************************** * Cooling device attributes * ***************************** diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c index 962de18..04659bf 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -944,6 +944,8 @@ create_s32_tzp_attr(k_pu); create_s32_tzp_attr(k_i); create_s32_tzp_attr(k_d); create_s32_tzp_attr(integral_cutoff); +create_s32_tzp_attr(slope); +create_s32_tzp_attr(offset); #undef create_s32_tzp_attr static struct device_attribute *dev_tzp_attrs[] = { @@ -953,6 +955,8 @@ static struct device_attribute *dev_tzp_attrs[] = { &dev_attr_k_i, &dev_attr_k_d, &dev_attr_integral_cutoff, + &dev_attr_slope, + &dev_attr_offset, }; static int create_tzp_attrs(struct device *dev) diff --git a/include/linux/thermal.h b/include/linux/thermal.h index 6bbe11c..037e9df 100644 --- a/include/linux/thermal.h +++ b/include/linux/thermal.h @@ -302,6 +302,17 @@ struct thermal_zone_params { /* threshold below which the error is no longer accumulated */ s32 integral_cutoff; + + /* + * @slope: slope of a linear temperature adjustment curve. + * Used by thermal zone drivers. + */ + int slope; + /* + * @offset: offset of a linear temperature adjustment curve. + * Used by thermal zone drivers (default 0). + */ + int offset; }; struct thermal_genl_event {
It is common to have a linear extrapolation from the current sensor readings and the actual temperature value. This is specially the case when the sensor is in use to extrapolate hotspots. This patch adds slope and offset constants for single sensor linear extrapolation equation. Because the same sensor can be use in different locations, from board to board, these constants are added as part of thermal_zone_params. The constants are available through sysfs. It is up to the device driver to determine the usage of these values. Signed-off-by: Eduardo Valentin <edubezval@gmail.com> --- Documentation/thermal/sysfs-api.txt | 16 ++++++++++++++++ drivers/thermal/thermal_core.c | 4 ++++ include/linux/thermal.h | 11 +++++++++++ 3 files changed, 31 insertions(+)