| Message ID | 20241219-skov-dt-updates-v1-3-38bf80dc22df@pengutronix.de (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | arm64: dts: imx8mp-skov: flesh out device trees | expand |
On Thu, Dec 19, 2024 at 08:25:27AM +0100, Ahmad Fatoum wrote: > The HDMI DDC pads can be muxed either to an i.MX I2C controller or > to a limited I2C controller within the Designware HDMI bridge. > > So far we muxed the pads to the HDMI bridge, but the i.MX I2C controller > is the better choice: Switch to the i.MX I2C controller because > > - We use DDC/CI commands for display brightness configuration, but the > Linux driver refuses[1] transfers to/from address 0x37, because the > controller doesn't support multi-byte requests. Designware HDMI Limited I2C controller doesn't support multi-byte requests and display brightness configuration by DDC/CI command need it. > > - The driver doesn't support I2C bus recovery, but we need that, > because some HDMI panels used with the board can be flaky. Designware HDMI Limited I2C controller doesn't support I2C bus recovery. > > As the i.MX I2C controller doesn't have either of these limitations, > let's make use of it instead. Reduntant. can be removed. Frank > > [1]: https://lore.kernel.org/all/20190722181945.244395-1-mka@chromium.org/ > > Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> > --- > .../boot/dts/freescale/imx8mp-skov-revb-hdmi.dts | 26 ++++++++++++++++++++-- > 1 file changed, 24 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/boot/dts/freescale/imx8mp-skov-revb-hdmi.dts b/arch/arm64/boot/dts/freescale/imx8mp-skov-revb-hdmi.dts > index c1ca69da3cb8..206116be8166 100644 > --- a/arch/arm64/boot/dts/freescale/imx8mp-skov-revb-hdmi.dts > +++ b/arch/arm64/boot/dts/freescale/imx8mp-skov-revb-hdmi.dts > @@ -9,12 +9,34 @@ / { > compatible = "skov,imx8mp-skov-revb-hdmi", "fsl,imx8mp"; > }; > > +&i2c5 { > + pinctrl-names = "default", "gpio"; > + pinctrl-0 = <&pinctrl_i2c5>; > + pinctrl-1 = <&pinctrl_i2c5_gpio>; > + scl-gpios = <&gpio3 26 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>; > + sda-gpios = <&gpio3 27 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>; > + clock-frequency = <100000>; > + status = "okay"; > +}; > + > &iomuxc { > pinctrl_hdmi: hdmigrp { > fsl,pins = < > - MX8MP_IOMUXC_HDMI_DDC_SCL__HDMIMIX_HDMI_SCL 0x1c3 > - MX8MP_IOMUXC_HDMI_DDC_SDA__HDMIMIX_HDMI_SDA 0x1c3 > MX8MP_IOMUXC_HDMI_HPD__HDMIMIX_HDMI_HPD 0x19 > >; > }; > + > + pinctrl_i2c5: i2c5grp { > + fsl,pins = < > + MX8MP_IOMUXC_HDMI_DDC_SCL__I2C5_SCL 0x400001c2 > + MX8MP_IOMUXC_HDMI_DDC_SDA__I2C5_SDA 0x400001c2 > + >; > + }; > + > + pinctrl_i2c5_gpio: i2c5gpiogrp { > + fsl,pins = < > + MX8MP_IOMUXC_HDMI_DDC_SCL__GPIO3_IO26 0x400001c2 > + MX8MP_IOMUXC_HDMI_DDC_SDA__GPIO3_IO27 0x400001c2 > + >; > + }; > }; > > -- > 2.39.5 >
Hello Frank, On 19.12.24 18:34, Frank Li wrote: > On Thu, Dec 19, 2024 at 08:25:27AM +0100, Ahmad Fatoum wrote: >> The HDMI DDC pads can be muxed either to an i.MX I2C controller or >> to a limited I2C controller within the Designware HDMI bridge. >> >> So far we muxed the pads to the HDMI bridge, but the i.MX I2C controller >> is the better choice: > > Switch to the i.MX I2C controller because > >> >> - We use DDC/CI commands for display brightness configuration, but the >> Linux driver refuses[1] transfers to/from address 0x37, because the >> controller doesn't support multi-byte requests. > > Designware HDMI Limited I2C controller doesn't support multi-byte > requests and display brightness configuration by DDC/CI command need it. > >> >> - The driver doesn't support I2C bus recovery, but we need that, >> because some HDMI panels used with the board can be flaky. > > Designware HDMI Limited I2C controller doesn't support I2C bus > recovery. > >> >> As the i.MX I2C controller doesn't have either of these limitations, >> let's make use of it instead. > > Reduntant. can be removed. Sorry, I am very much open to review feedback, but I fail to see how your subjective take improves things. Thanks, Ahmad > > Frank >> >> [1]: https://lore.kernel.org/all/20190722181945.244395-1-mka@chromium.org/ >> >> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> >> --- >> .../boot/dts/freescale/imx8mp-skov-revb-hdmi.dts | 26 ++++++++++++++++++++-- >> 1 file changed, 24 insertions(+), 2 deletions(-) >> >> diff --git a/arch/arm64/boot/dts/freescale/imx8mp-skov-revb-hdmi.dts b/arch/arm64/boot/dts/freescale/imx8mp-skov-revb-hdmi.dts >> index c1ca69da3cb8..206116be8166 100644 >> --- a/arch/arm64/boot/dts/freescale/imx8mp-skov-revb-hdmi.dts >> +++ b/arch/arm64/boot/dts/freescale/imx8mp-skov-revb-hdmi.dts >> @@ -9,12 +9,34 @@ / { >> compatible = "skov,imx8mp-skov-revb-hdmi", "fsl,imx8mp"; >> }; >> >> +&i2c5 { >> + pinctrl-names = "default", "gpio"; >> + pinctrl-0 = <&pinctrl_i2c5>; >> + pinctrl-1 = <&pinctrl_i2c5_gpio>; >> + scl-gpios = <&gpio3 26 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>; >> + sda-gpios = <&gpio3 27 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>; >> + clock-frequency = <100000>; >> + status = "okay"; >> +}; >> + >> &iomuxc { >> pinctrl_hdmi: hdmigrp { >> fsl,pins = < >> - MX8MP_IOMUXC_HDMI_DDC_SCL__HDMIMIX_HDMI_SCL 0x1c3 >> - MX8MP_IOMUXC_HDMI_DDC_SDA__HDMIMIX_HDMI_SDA 0x1c3 >> MX8MP_IOMUXC_HDMI_HPD__HDMIMIX_HDMI_HPD 0x19 >> >; >> }; >> + >> + pinctrl_i2c5: i2c5grp { >> + fsl,pins = < >> + MX8MP_IOMUXC_HDMI_DDC_SCL__I2C5_SCL 0x400001c2 >> + MX8MP_IOMUXC_HDMI_DDC_SDA__I2C5_SDA 0x400001c2 >> + >; >> + }; >> + >> + pinctrl_i2c5_gpio: i2c5gpiogrp { >> + fsl,pins = < >> + MX8MP_IOMUXC_HDMI_DDC_SCL__GPIO3_IO26 0x400001c2 >> + MX8MP_IOMUXC_HDMI_DDC_SDA__GPIO3_IO27 0x400001c2 >> + >; >> + }; >> }; >> >> -- >> 2.39.5 >> >
On Thu, Dec 19, 2024 at 06:43:56PM +0100, Ahmad Fatoum wrote: > Hello Frank, > > On 19.12.24 18:34, Frank Li wrote: > > On Thu, Dec 19, 2024 at 08:25:27AM +0100, Ahmad Fatoum wrote: > >> The HDMI DDC pads can be muxed either to an i.MX I2C controller or > >> to a limited I2C controller within the Designware HDMI bridge. > >> > >> So far we muxed the pads to the HDMI bridge, but the i.MX I2C controller > >> is the better choice: > > > > Switch to the i.MX I2C controller because > > > >> > >> - We use DDC/CI commands for display brightness configuration, but the > >> Linux driver refuses[1] transfers to/from address 0x37, because the > >> controller doesn't support multi-byte requests. > > > > Designware HDMI Limited I2C controller doesn't support multi-byte > > requests and display brightness configuration by DDC/CI command need it. > > > >> > >> - The driver doesn't support I2C bus recovery, but we need that, > >> because some HDMI panels used with the board can be flaky. > > > > Designware HDMI Limited I2C controller doesn't support I2C bus > > recovery. > > > >> > >> As the i.MX I2C controller doesn't have either of these limitations, > >> let's make use of it instead. > > > > Reduntant. can be removed. > > Sorry, I am very much open to review feedback, but I fail to see how > your subjective take improves things. Ref https://docs.kernel.org/process/submitting-patches.html "Describe your changes in imperative mood, e.g. “make xyzzy do frotz” instead of “[This patch] makes xyzzy do frotz” or “[I] changed xyzzy to do frotz”, as if you are giving orders to the codebase to change its behaviour." Avoid use "we(same as "I" in above example) ..." Frank > > Thanks, > Ahmad > > > > > > > > Frank > >> > >> [1]: https://lore.kernel.org/all/20190722181945.244395-1-mka@chromium.org/ > >> > >> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> > >> --- > >> .../boot/dts/freescale/imx8mp-skov-revb-hdmi.dts | 26 ++++++++++++++++++++-- > >> 1 file changed, 24 insertions(+), 2 deletions(-) > >> > >> diff --git a/arch/arm64/boot/dts/freescale/imx8mp-skov-revb-hdmi.dts b/arch/arm64/boot/dts/freescale/imx8mp-skov-revb-hdmi.dts > >> index c1ca69da3cb8..206116be8166 100644 > >> --- a/arch/arm64/boot/dts/freescale/imx8mp-skov-revb-hdmi.dts > >> +++ b/arch/arm64/boot/dts/freescale/imx8mp-skov-revb-hdmi.dts > >> @@ -9,12 +9,34 @@ / { > >> compatible = "skov,imx8mp-skov-revb-hdmi", "fsl,imx8mp"; > >> }; > >> > >> +&i2c5 { > >> + pinctrl-names = "default", "gpio"; > >> + pinctrl-0 = <&pinctrl_i2c5>; > >> + pinctrl-1 = <&pinctrl_i2c5_gpio>; > >> + scl-gpios = <&gpio3 26 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>; > >> + sda-gpios = <&gpio3 27 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>; > >> + clock-frequency = <100000>; > >> + status = "okay"; > >> +}; > >> + > >> &iomuxc { > >> pinctrl_hdmi: hdmigrp { > >> fsl,pins = < > >> - MX8MP_IOMUXC_HDMI_DDC_SCL__HDMIMIX_HDMI_SCL 0x1c3 > >> - MX8MP_IOMUXC_HDMI_DDC_SDA__HDMIMIX_HDMI_SDA 0x1c3 > >> MX8MP_IOMUXC_HDMI_HPD__HDMIMIX_HDMI_HPD 0x19 > >> >; > >> }; > >> + > >> + pinctrl_i2c5: i2c5grp { > >> + fsl,pins = < > >> + MX8MP_IOMUXC_HDMI_DDC_SCL__I2C5_SCL 0x400001c2 > >> + MX8MP_IOMUXC_HDMI_DDC_SDA__I2C5_SDA 0x400001c2 > >> + >; > >> + }; > >> + > >> + pinctrl_i2c5_gpio: i2c5gpiogrp { > >> + fsl,pins = < > >> + MX8MP_IOMUXC_HDMI_DDC_SCL__GPIO3_IO26 0x400001c2 > >> + MX8MP_IOMUXC_HDMI_DDC_SDA__GPIO3_IO27 0x400001c2 > >> + >; > >> + }; > >> }; > >> > >> -- > >> 2.39.5 > >> > > > > > -- > Pengutronix e.K. | | > Steuerwalder Str. 21 | http://www.pengutronix.de/ | > 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | > Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
diff --git a/arch/arm64/boot/dts/freescale/imx8mp-skov-revb-hdmi.dts b/arch/arm64/boot/dts/freescale/imx8mp-skov-revb-hdmi.dts index c1ca69da3cb8..206116be8166 100644 --- a/arch/arm64/boot/dts/freescale/imx8mp-skov-revb-hdmi.dts +++ b/arch/arm64/boot/dts/freescale/imx8mp-skov-revb-hdmi.dts @@ -9,12 +9,34 @@ / { compatible = "skov,imx8mp-skov-revb-hdmi", "fsl,imx8mp"; }; +&i2c5 { + pinctrl-names = "default", "gpio"; + pinctrl-0 = <&pinctrl_i2c5>; + pinctrl-1 = <&pinctrl_i2c5_gpio>; + scl-gpios = <&gpio3 26 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>; + sda-gpios = <&gpio3 27 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>; + clock-frequency = <100000>; + status = "okay"; +}; + &iomuxc { pinctrl_hdmi: hdmigrp { fsl,pins = < - MX8MP_IOMUXC_HDMI_DDC_SCL__HDMIMIX_HDMI_SCL 0x1c3 - MX8MP_IOMUXC_HDMI_DDC_SDA__HDMIMIX_HDMI_SDA 0x1c3 MX8MP_IOMUXC_HDMI_HPD__HDMIMIX_HDMI_HPD 0x19 >; }; + + pinctrl_i2c5: i2c5grp { + fsl,pins = < + MX8MP_IOMUXC_HDMI_DDC_SCL__I2C5_SCL 0x400001c2 + MX8MP_IOMUXC_HDMI_DDC_SDA__I2C5_SDA 0x400001c2 + >; + }; + + pinctrl_i2c5_gpio: i2c5gpiogrp { + fsl,pins = < + MX8MP_IOMUXC_HDMI_DDC_SCL__GPIO3_IO26 0x400001c2 + MX8MP_IOMUXC_HDMI_DDC_SDA__GPIO3_IO27 0x400001c2 + >; + }; };
The HDMI DDC pads can be muxed either to an i.MX I2C controller or to a limited I2C controller within the Designware HDMI bridge. So far we muxed the pads to the HDMI bridge, but the i.MX I2C controller is the better choice: - We use DDC/CI commands for display brightness configuration, but the Linux driver refuses[1] transfers to/from address 0x37, because the controller doesn't support multi-byte requests. - The driver doesn't support I2C bus recovery, but we need that, because some HDMI panels used with the board can be flaky. As the i.MX I2C controller doesn't have either of these limitations, let's make use of it instead. [1]: https://lore.kernel.org/all/20190722181945.244395-1-mka@chromium.org/ Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> --- .../boot/dts/freescale/imx8mp-skov-revb-hdmi.dts | 26 ++++++++++++++++++++-- 1 file changed, 24 insertions(+), 2 deletions(-)