2024-05-27 16:15:08

by Max Krummenacher

Subject: [PATCH v1 0/2] arm64: dts: freescale: imx8m{m|p}: don't limit i2c2 max. clock

From: Max Krummenacher <[email protected]>


This sets the I2C clock frequency to something people expect it to
be by default.

For I2C DDC we do want to lower the I2C clock to have more reliable
communication. However that should be done where the I2C bus is
assigned to a HDMI DDC, not as the default.


Max Krummenacher (2):
arm64: dts: freescale: imx8mm-verdin: don't limit i2c2 max. clock
arm64: dts: freescale: imx8mp-verdin: don't limit i2c2 max. clock

arch/arm64/boot/dts/freescale/imx8mm-verdin.dtsi | 2 +-
arch/arm64/boot/dts/freescale/imx8mp-verdin.dtsi | 3 +--
2 files changed, 2 insertions(+), 3 deletions(-)

--
2.42.0

2024-05-27 16:15:24

by Max Krummenacher

Subject: [PATCH v1 1/2] arm64: dts: freescale: imx8mm-verdin: don't limit i2c2 max. clock

From: Max Krummenacher <[email protected]>

Verdin I2C2 may be used to access other I2C devices apart from serving
as an HDMI DDC channel.
Thus do not limit the used I2C clock frequency to 10kHz in the module
specific device tree part.
If an overlay configures i2c2 as DDC the overlay is also responsible
to cope with an appropriate I2C clock.

Signed-off-by: Max Krummenacher <[email protected]>
---

arch/arm64/boot/dts/freescale/imx8mm-verdin.dtsi | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/freescale/imx8mm-verdin.dtsi b/arch/arm64/boot/dts/freescale/imx8mm-verdin.dtsi
index 4768b05fd765..82bbcec525d7 100644
--- a/arch/arm64/boot/dts/freescale/imx8mm-verdin.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mm-verdin.dtsi
@@ -547,7 +547,7 @@ eeprom@50 {

/* Verdin I2C_2_DSI */
&i2c2 {
- clock-frequency = <10000>;
+ clock-frequency = <400000>;
pinctrl-names = "default", "gpio";
pinctrl-0 = <&pinctrl_i2c2>;
pinctrl-1 = <&pinctrl_i2c2_gpio>;
--
2.42.0

2024-05-27 16:24:19

by Max Krummenacher

Subject: [PATCH v1 2/2] arm64: dts: freescale: imx8mp-verdin: don't limit i2c2 max. clock

From: Max Krummenacher <[email protected]>

Verdin I2C2 may be used to access other I2C devices apart from serving
as an HDMI DDC channel.
Thus do not limit the used I2C clock frequency to 10kHz in the module
specific device tree part.
If an overlay configures i2c2 as DDC the overlay is also responsible
to cope with an appropriate I2C clock.

Signed-off-by: Max Krummenacher <[email protected]>

---

arch/arm64/boot/dts/freescale/imx8mp-verdin.dtsi | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/freescale/imx8mp-verdin.dtsi b/arch/arm64/boot/dts/freescale/imx8mp-verdin.dtsi
index aef4bef4bccd..3c6b47edd4c1 100644
--- a/arch/arm64/boot/dts/freescale/imx8mp-verdin.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mp-verdin.dtsi
@@ -650,8 +650,7 @@ eeprom@50 {

/* Verdin I2C_2_DSI */
&i2c2 {
- /* Lower frequency to avoid DDC/EDID issues with certain displays/screens. */
- clock-frequency = <10000>;
+ clock-frequency = <400000>;
pinctrl-names = "default", "gpio";
pinctrl-0 = <&pinctrl_i2c2>;
pinctrl-1 = <&pinctrl_i2c2_gpio>;
--
2.42.0

2024-06-16 02:32:59

by Shawn Guo

Subject: Re: [PATCH v1 0/2] arm64: dts: freescale: imx8m{m|p}: don't limit i2c2 max. clock

On Mon, May 27, 2024 at 06:03:44PM +0200, [email protected] wrote:
> From: Max Krummenacher <[email protected]>
>
>
> This sets the I2C clock frequency to something people expect it to
> be by default.
>
> For I2C DDC we do want to lower the I2C clock to have more reliable
> communication. However that should be done where the I2C bus is
> assigned to a HDMI DDC, not as the default.
>
>
> Max Krummenacher (2):
> arm64: dts: freescale: imx8mm-verdin: don't limit i2c2 max. clock
> arm64: dts: freescale: imx8mp-verdin: don't limit i2c2 max. clock

Applied both, thanks!