mtd: rawnand: intel: Read the chip-select line from the correct OF node

The chip select has to be read from the flash node which is a child node
of the NAND controller.

Fixes: 0b1039f0 ("mtd: rawnand: Add NAND controller support on Intel LGM SoC")
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20220702231227.1579176-4-martin.blumenstingl@googlemail.com

drivers/mtd/nand/raw/intel-nand-controller.c

@@ -16,6 +16,7 @@
 #include <linux/mtd/rawnand.h>
 #include <linux/mtd/nand.h>
 
+#include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
@@ -580,6 +581,7 @@ static int ebu_nand_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct ebu_nand_controller *ebu_host;
+	struct device_node *chip_np;
 	struct nand_chip *nand;
 	struct mtd_info *mtd;
 	struct resource *res;
@@ -604,7 +606,12 @@ static int ebu_nand_probe(struct platform_device *pdev)
 	if (IS_ERR(ebu_host->hsnand))
 		return PTR_ERR(ebu_host->hsnand);
 
-	ret = device_property_read_u32(dev, "reg", &cs);
+	chip_np = of_get_next_child(dev->of_node, NULL);
+	if (!chip_np)
+		return dev_err_probe(dev, -EINVAL,
+				     "Could not find child node for the NAND chip\n");
+
+	ret = of_property_read_u32(chip_np, "reg", &cs);
 	if (ret) {
 		dev_err(dev, "failed to get chip select: %d\n", ret);
 		return ret;
@@ -660,7 +667,7 @@ static int ebu_nand_probe(struct platform_device *pdev)
 	writel(ebu_host->cs[cs].addr_sel | EBU_ADDR_MASK(5) | EBU_ADDR_SEL_REGEN,
 	       ebu_host->ebu + EBU_ADDR_SEL(cs));
 
-	nand_set_flash_node(&ebu_host->chip, dev->of_node);
+	nand_set_flash_node(&ebu_host->chip, chip_np);
 
 	mtd = nand_to_mtd(&ebu_host->chip);
 	if (!mtd->name) {