[PATCH 2/7] spi: sh-msiof: ignore driver probing if it was MSIOF Sound

[Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>]

Renesas MSIOF (Clock-Synchronized Serial Interface with FIFO) can work as
both SPI and I2S. MSIOF-I2S will use Audio Graph Card/Card2 driver which
Of-Graph in DT.

MSIOF-SPI/I2S are using same DT compatible properties.
MSIOF-I2S         uses Of-Graph for Audio-Graph-Card/Card2,
MSIOF-SPI doesn't use  Of-Graph.

Check "port" node when driver probing

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
---
 drivers/spi/spi-sh-msiof.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/spi/spi-sh-msiof.c b/drivers/spi/spi-sh-msiof.c
index 8a98c313548e..51415131eff1 100644
--- a/drivers/spi/spi-sh-msiof.c
+++ b/drivers/spi/spi-sh-msiof.c
@@ -20,6 +20,7 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_graph.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/sh_dma.h>
@@ -1276,10 +1277,19 @@ static int sh_msiof_spi_probe(struct platform_device *pdev)
 	const struct sh_msiof_chipdata *chipdata;
 	struct sh_msiof_spi_info *info;
 	struct sh_msiof_spi_priv *p;
+	struct device_node *port;
 	unsigned long clksrc;
 	int i;
 	int ret;
 
+	/* Check whether MSIOF is used as I2S mode or SPI mode by checking "port" node */
+	port = of_graph_get_next_port(pdev->dev.of_node, NULL);
+	if (port) {
+		/* It was MSIOF-I2S */
+		of_node_put(port);
+		return -ENODEV;
+	}
+
 	chipdata = of_device_get_match_data(&pdev->dev);
 	if (chipdata) {
 		info = sh_msiof_spi_parse_dt(&pdev->dev);
-- 
2.43.0