On 7/26/23 01:13, Chris Packham wrote:
There is an Errata with the built-in I2C controller where various I2C
hardware errors cause a complete lockup of the CPU (which eventually
results in an watchdog reset).
Put the I2C MPP pins into GPIO mode and use the i2c-gpio driver instead.
This uses a bit-banged implementation of an I2C controller and avoids
triggering the Errata.
Signed-off-by: Chris Packham <judge.pack...@gmail.com>
Reviewed-by: Stefan Roese <s...@denx.de>
Applied to u-boot-marvell/master
Thanks,
Stefan
---
Changes in v2:
- Update i2c0 alias
- Move i2c-gpio definition to root of device tree
- Remove &i2c0 instead of just disabling it
- Add r-by from Stefan
arch/arm/dts/ac5-98dx35xx-atl-x240.dts | 30 ++++++++++++++++++++------
configs/x240_defconfig | 1 +
2 files changed, 24 insertions(+), 7 deletions(-)
diff --git a/arch/arm/dts/ac5-98dx35xx-atl-x240.dts
b/arch/arm/dts/ac5-98dx35xx-atl-x240.dts
index 820ec18b4355..c19b25925ba2 100644
--- a/arch/arm/dts/ac5-98dx35xx-atl-x240.dts
+++ b/arch/arm/dts/ac5-98dx35xx-atl-x240.dts
@@ -16,7 +16,7 @@
gpio0 = &gpio0;
gpio1 = &gpio1;
spi0 = &spi0;
- i2c0 = &i2c0;
+ i2c0 = &i2cgpio;
usb0 = &usb0;
pinctrl0 = &pinctrl0;
};
@@ -40,6 +40,19 @@
default-state = "on";
};
};
+
+ i2cgpio: i2c-gpio-0 {
+ compatible = "i2c-gpio";
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ pinctrl-names = "default";
+ pinctrl-0 = <&i2c0_gpio>;
+ scl-gpios = <&gpio0 26 (GPIO_ACTIVE_HIGH |
GPIO_OPEN_DRAIN)>;
+ sda-gpios = <&gpio0 27 (GPIO_ACTIVE_HIGH |
GPIO_OPEN_DRAIN)>;
+ i2c-gpio,delay-us = <2>;
+ status = "okay";
+ };
};
&nand {
@@ -70,9 +83,7 @@
status = "okay";
};
-&i2c0 {
- status = "okay";
-
+&i2cgpio {
mux@71 {
#address-cells = <1>;
#size-cells = <0>;
@@ -177,8 +188,8 @@
* LED_OE_N [23]
* USB_PWR_FLT_N [24]
* SFP_INT_N [25]
- * I2C0_SCL [26]
- * I2C0_SDA [27]
+ * I2C0_SCL [26] (GPIO)
+ * I2C0_SDA [27] (GPIO)
* USB_EN [28]
* MONITOR_INT_N [29]
* XM1_MDC [30]
@@ -201,7 +212,7 @@
/* 0 1 2 3 4 5 6 7 8 9 */
pin-func = < 0xff 0xff 0xff 0xff 0xff 0xff 0xff 0xff 0xff 0xff
0xff 0xff 1 1 1 1 0xff 0xff 0 0
- 0 0 0 0 0 0 1 1 0 0
+ 0 0 0 0 0 0 0xff 0xff 0 0
1 1 1 1 0 0 0 0 0 0
0 0 0 1 1 1 >;
@@ -209,4 +220,9 @@
marvell,pins = <0 1 2 3 4 5 6 7 8 9 10 11 16 17>;
marvell,function = <2>;
};
+
+ i2c0_gpio: i2c0-gpio-pins {
+ marvell,pins = <26 27>;
+ marvell,function = <0>;
+ };
};
diff --git a/configs/x240_defconfig b/configs/x240_defconfig
index a78cb3ce6cbf..7d2b8603e6f4 100644
--- a/configs/x240_defconfig
+++ b/configs/x240_defconfig
@@ -42,6 +42,7 @@ CONFIG_CLK_MVEBU=y
CONFIG_GPIO_HOG=y
CONFIG_DM_PCA953X=y
CONFIG_DM_I2C=y
+CONFIG_DM_I2C_GPIO=y
CONFIG_SYS_I2C_MVTWSI=y
CONFIG_I2C_MUX=y
CONFIG_I2C_MUX_PCA954x=y
Viele Grüße,
Stefan Roese
--
DENX Software Engineering GmbH, Managing Director: Erika Unter
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-51 Fax: (+49)-8142-66989-80 Email: s...@denx.de
