ARM: dts: ux500: Drop pulls on I2C buses

The I2C block in the Ux500 uses internal pull-ups on the
SoC, in fact it has to: in HS mode, the I2C block will need
to autonomously take control over the pull-up line to do
its job. This can be clearly seen from the SoC manual which
states that the silicon has a line named "en_cspu_hs" which
enables current source pull-up for high speed mode. Another
hint is that the vendor code tree never enabled the pull
up on these lines, despite being deployed on boards that
lack external pull-up resistors.

Tested on the Ux500 reference designs without any problems.

Cc: Stephan Gerhold <stephan@gerhold.net>
Reported-by: Stephan Gerhold <stephan@gerhold.net>
Link: https://lore.kernel.org/r/20191126123116.56244-1-linus.walleij@linaro.org
Reviewed-by: Stephan Gerhold <stephan@gerhold.net>
Tested-by: Stephan Gerhold <stephan@gerhold.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/arch/arm/boot/dts/ste-dbx5x0-pinctrl.dtsi b/arch/arm/boot/dts/ste-dbx5x0-pinctrl.dtsi
index e85a08ad2ea74e507a53e17afd85dabdbe080c64..7bf7a2d34cbc36a7d352f8b75332514542fc2b17 100644 (file)
--- a/arch/arm/boot/dts/ste-dbx5x0-pinctrl.dtsi
+++ b/arch/arm/boot/dts/ste-dbx5x0-pinctrl.dtsi
@@ -130,7 +130,7 @@
                        };
                        default_cfg1 {
                                pins = "GPIO147_C15", "GPIO148_B16"; /* SDA/SCL */
-                               ste,config = <&in_pu>;
+                               ste,config = <&in_nopull>;
                        };
                };
 
@@ -150,7 +150,7 @@
                        };
                        default_cfg1 {
                                pins = "GPIO16_AD3", "GPIO17_AD4"; /* SDA/SCL */
-                               ste,config = <&in_pu>;
+                               ste,config = <&in_nopull>;
                        };
                };
 
@@ -170,7 +170,7 @@
                        };
                        default_cfg1 {
                                pins = "GPIO10_AF5", "GPIO11_AG4"; /* SDA/SCL */
-                               ste,config = <&in_pu>;
+                               ste,config = <&in_nopull>;
                        };
                };
 
@@ -190,7 +190,7 @@
                        };
                        default_cfg1 {
                                pins = "GPIO229_AG7", "GPIO230_AF7"; /* SDA/SCL */
-                               ste,config = <&in_pu>;
+                               ste,config = <&in_nopull>;
                        };
                };
 
@@ -214,7 +214,7 @@
                        };
                        default_cfg1 {
                                pins = "GPIO4_AH6", "GPIO5_AG6"; /* SDA/SCL */
-                               ste,config = <&in_pu>;
+                               ste,config = <&in_nopull>;
                        };
                };