Commit bcf14774 authored by Andrey Smirnov's avatar Andrey Smirnov Committed by Shawn Guo

ARM: dts: imx51-zii-rdu1: Make sure SD1_WP is low

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
output-high GPIO hog in an effort to minimize current consumption.

Cc: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: default avatarAndrey Smirnov <andrew.smirnov@gmail.com>
Tested-By: default avatarNikita Yushchenko <nikita.yoush@cogentembedded.com>
Signed-off-by: default avatarShawn Guo <shawnguo@kernel.org>
parent 6e21e4c2
......@@ -476,6 +476,17 @@ &fec {
status = "okay";
};
&gpio1 {
unused-sd3-wp-gpio {
/*
* See pinctrl_esdhc1 below for more details on this
*/
gpio-hog;
gpios = <1 GPIO_ACTIVE_HIGH>;
output-high;
};
};
&i2c2 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_i2c2>;
......@@ -668,6 +679,23 @@ MX51_PAD_SD1_DATA0__SD1_DATA0 0x20d5
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
>;
};
......
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