mmc: sdhci-iproc: handle mmc_of_parse() errors during probe

BugLink: https://bugs.launchpad.net/bugs/1818803

commit 2bd44dad upstream.

We need to handle mmc_of_parse() errors during probe.

This finally fixes the wifi regression on Raspberry Pi 3 series.
In error case the wifi chip was permanently in reset because of
the power sequence depending on the deferred probe of the GPIO expander.

Fixes: b580c52d ("mmc: sdhci-iproc: add IPROC SDHCI driver")
Cc: stable@vger.kernel.org
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Juerg Haefliger <juergh@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

drivers/mmc/host/sdhci-iproc.c

@@ -217,7 +217,10 @@ static int sdhci_iproc_probe(struct platform_device *pdev)
 
 	iproc_host->data = iproc_data;
 
-	mmc_of_parse(host->mmc);
+	ret = mmc_of_parse(host->mmc);
+	if (ret)
+		goto err;
+
 	sdhci_get_of_property(pdev);
 
 	/* Enable EMMC 1/8V DDR capable */