Make sure that MX51_PAD_GPIO1_1 does not remain configure as ALT0/SD1_WP (it is out of reset). This is needed because of external pull-up resistor attached to that pad that, when left unchanged, will drive SD1_WP high preventing eSDHC1/eMMC from working correctly.
To fix that add a pinmux configuration line configureing the pad to function as a GPIO. While we are at it, add a corresponding input GPIO hog in an effort to minimize current consumption. Cc: Nikita Yushchenko <[email protected]> Cc: Shawn Guo <[email protected]> Cc: Fabio Estevam <[email protected]> Cc: Lucas Stach <[email protected]> Cc: Chris Healy <[email protected]> Cc: Rob Herring <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Signed-off-by: Andrey Smirnov <[email protected]> --- arch/arm/boot/dts/imx51-zii-rdu1.dts | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/arch/arm/boot/dts/imx51-zii-rdu1.dts b/arch/arm/boot/dts/imx51-zii-rdu1.dts index df9eca94d812..d484e7e46b27 100644 --- a/arch/arm/boot/dts/imx51-zii-rdu1.dts +++ b/arch/arm/boot/dts/imx51-zii-rdu1.dts @@ -476,6 +476,17 @@ status = "okay"; }; +&gpio1 { + unused-sd3-wp-gpio { + /* + * See pinctrl_esdhc1 below for more details on this + */ + gpio-hog; + gpios = <1 GPIO_ACTIVE_HIGH>; + input; + }; +}; + &i2c2 { pinctrl-names = "default"; pinctrl-0 = <&pinctrl_i2c2>; @@ -660,6 +671,23 @@ MX51_PAD_SD1_DATA1__SD1_DATA1 0x20d5 MX51_PAD_SD1_DATA2__SD1_DATA2 0x20d5 MX51_PAD_SD1_DATA3__SD1_DATA3 0x20d5 + /* + * GPIO1_1 is not directly used by eSDHC1 in + * any capacity, but earlier versions of RDU1 + * used that pin as WP GPIO for eSDHC3 and + * because of that that pad has an external + * pull-up resistor. This is problematic + * because out of reset the pad is configured + * as ALT0 which serves as SD1_WP, which, when + * pulled high by and external pull-up, will + * inhibit execution of any write request to + * attached eMMC device. + * + * To avoid this problem we configure the pad + * to ALT1/GPIO and avoid driving SD1_WP + * signal high. + */ + MX51_PAD_GPIO1_1__GPIO1_1 0x0000 >; }; -- 2.17.0
