| Message ID | 20250226153929.274562-2-mathis.foerst@mt.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | MT9M114 driver bugfix and improvements | expand |
Hi Mathis, Please see which subject prefix has been used in the past for these bindings. On Wed, Feb 26, 2025 at 04:39:22PM +0100, Mathis Foerst wrote: > The MT9M114 sensor has an internal PLL that generates the required SYSCLK > from EXTCLK. It also has the option to bypass the PLL and use EXTCLK > directly as SYSCLK. > The current driver implementation uses a hardcoded PLL configuration that > requires a specific EXTCLK frequency. Depending on the available clocks, > it can be desirable to use a different PLL configuration or to bypass it. > > Add the 'bypass-pll' property to the MT9M114 DT-bindings to allow selecting > the PLL bypass mode. > > Signed-off-by: Mathis Foerst <mathis.foerst@mt.com> > --- > Documentation/devicetree/bindings/media/i2c/onnn,mt9m114.yaml | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/Documentation/devicetree/bindings/media/i2c/onnn,mt9m114.yaml b/Documentation/devicetree/bindings/media/i2c/onnn,mt9m114.yaml > index f6b87892068a..72e258d57186 100644 > --- a/Documentation/devicetree/bindings/media/i2c/onnn,mt9m114.yaml > +++ b/Documentation/devicetree/bindings/media/i2c/onnn,mt9m114.yaml > @@ -70,6 +70,10 @@ properties: > - bus-type > - link-frequencies > > + onnn,bypass-pll: > + description: Bypass the internal PLL of the sensor to use EXTCLK directly as SYSCLK. > + type: boolean > + But on the content itself: do you need this? Could you instead compare the external clock frequency to the link-frequencies property value(s)? > required: > - compatible > - reg
Hi Sakari On Wed, Feb 26, 2025 at 04:08:39PM +0000, Sakari Ailus wrote: > Hi Mathis, > > Please see which subject prefix has been used in the past for these > bindings. Yes, I'm sorry for that. I adapted the subjects of the patches. > > On Wed, Feb 26, 2025 at 04:39:22PM +0100, Mathis Foerst wrote: > > The MT9M114 sensor has an internal PLL that generates the required SYSCLK > > from EXTCLK. It also has the option to bypass the PLL and use EXTCLK > > directly as SYSCLK. > > The current driver implementation uses a hardcoded PLL configuration that > > requires a specific EXTCLK frequency. Depending on the available clocks, > > it can be desirable to use a different PLL configuration or to bypass it. > > > > Add the 'bypass-pll' property to the MT9M114 DT-bindings to allow selecting > > the PLL bypass mode. > > > > Signed-off-by: Mathis Foerst <mathis.foerst@mt.com> > > --- > > Documentation/devicetree/bindings/media/i2c/onnn,mt9m114.yaml | 4 ++++ > > 1 file changed, 4 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/media/i2c/onnn,mt9m114.yaml b/Documentation/devicetree/bindings/media/i2c/onnn,mt9m114.yaml > > index f6b87892068a..72e258d57186 100644 > > --- a/Documentation/devicetree/bindings/media/i2c/onnn,mt9m114.yaml > > +++ b/Documentation/devicetree/bindings/media/i2c/onnn,mt9m114.yaml > > @@ -70,6 +70,10 @@ properties: > > - bus-type > > - link-frequencies > > > > + onnn,bypass-pll: > > + description: Bypass the internal PLL of the sensor to use EXTCLK directly as SYSCLK. > > + type: boolean > > + > > But on the content itself: do you need this? Could you instead compare the > external clock frequency to the link-frequencies property value(s)? That should also work. I removed the DT binding and let the driver check if EXTCLK matches the required SYSCLK for the given link frequency to decide if the PLL should be bypassed. > > > required: > > - compatible > > - reg > > -- > Regards, > > Sakari Ailus Best regards, Mathis Foerst
diff --git a/Documentation/devicetree/bindings/media/i2c/onnn,mt9m114.yaml b/Documentation/devicetree/bindings/media/i2c/onnn,mt9m114.yaml index f6b87892068a..72e258d57186 100644 --- a/Documentation/devicetree/bindings/media/i2c/onnn,mt9m114.yaml +++ b/Documentation/devicetree/bindings/media/i2c/onnn,mt9m114.yaml @@ -70,6 +70,10 @@ properties: - bus-type - link-frequencies + onnn,bypass-pll: + description: Bypass the internal PLL of the sensor to use EXTCLK directly as SYSCLK. + type: boolean + required: - compatible - reg
The MT9M114 sensor has an internal PLL that generates the required SYSCLK from EXTCLK. It also has the option to bypass the PLL and use EXTCLK directly as SYSCLK. The current driver implementation uses a hardcoded PLL configuration that requires a specific EXTCLK frequency. Depending on the available clocks, it can be desirable to use a different PLL configuration or to bypass it. Add the 'bypass-pll' property to the MT9M114 DT-bindings to allow selecting the PLL bypass mode. Signed-off-by: Mathis Foerst <mathis.foerst@mt.com> --- Documentation/devicetree/bindings/media/i2c/onnn,mt9m114.yaml | 4 ++++ 1 file changed, 4 insertions(+)