[PATCH v1 3/3] xea: config: Disable CONFIG_SPL_OF_PLATDATA_PARENT on XEA (imx28)

[Lukasz Majewski <lukma@denx.de>]

On the XEA board (imx28) one needs in the SPL support for GPIO, MMC and
SPI. Two last ones are necessary for booting the device. The GPIO support
allows deciding which medium will be used. For example the GPIO DTS node
(gpio at 0 at imx28.dtsi) has pinctrl parent (pinctrl at 80018000) for which we
don't need driver asigned for correct operation.
In the spl/dts/dt-platdata.c the gpio at 0 has index 4 and its parent -
pinctrl at 80018000 has index 5.

In the bind_drivers_pass() function (at drivers/core/lists.c) call to
device_bind_by_name() for `fsl_imx23_pinctrl` returns -2, which is
expected.

With current setup - when the SPL_OF_PLATDATA_PARENT=y
The gpio at 0 node with index 4 is skipped as its parent with 5 is not yet
bound. It cannot be as we don't need and provide the driver for it.
As a result the gpio at 0 is never bound and we end up with bricked board in
the SPL stage.

When CONFIG_SPL_OF_PLATDATA_PARENT is NOT set, all entries from
spl/dts/dt-platdata.c are scanned in ascending index order, so gpio at 0 is
properly initialized. For `fsl_imx_pinctrl` we simply check 10 times if
the driver for is available (which is not) and exit.

As a result the GPIOs are initialized and can be used in early SPL stage.
This commit fixes XEA regression introduced with e41651fffda7da55f6.

Signed-off-by: Lukasz Majewski <lukma@denx.de>

---

 configs/imx28_xea_defconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/configs/imx28_xea_defconfig b/configs/imx28_xea_defconfig
index e418d8c9e9..2e1d060024 100644
--- a/configs/imx28_xea_defconfig
+++ b/configs/imx28_xea_defconfig
@@ -65,6 +65,7 @@ CONFIG_OF_CONTROL=y
 CONFIG_SPL_OF_CONTROL=y
 CONFIG_OF_SPL_REMOVE_PROPS="pinctrl-0 pinctrl-names clock-names interrupt-parent interrupts"
 CONFIG_SPL_OF_PLATDATA=y
+# CONFIG_SPL_OF_PLATDATA_PARENT is not set
 CONFIG_ENV_OVERWRITE=y
 CONFIG_ENV_IS_IN_SPI_FLASH=y
 CONFIG_USE_ENV_SPI_BUS=y
-- 
2.20.1