[PATCH] can: c_can: Use platform id data when OF data is absent

[Pengpeng Hou]

The platform driver keeps controller metadata in both the OF match table
and the platform id table.  Probe reads the metadata with
device_get_match_data(), which does not fall back to platform id-table
driver_data.

When the device is matched through the platform id table, drvdata can
therefore be NULL before it is dereferenced for msg_obj_num and the
controller type.  Fall back to platform_get_device_id() when firmware
match data is not available.

Signed-off-by: Pengpeng Hou <pengpeng@xxxxxxxxxxx>
---
 drivers/net/can/c_can/c_can_platform.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/net/can/c_can/c_can_platform.c b/drivers/net/can/c_can/c_can_platform.c
index 19c86b94a40e..564c9e5b4c2c 100644
--- a/drivers/net/can/c_can/c_can_platform.c
+++ b/drivers/net/can/c_can/c_can_platform.c
@@ -263,9 +263,17 @@ static int c_can_plat_probe(struct platform_device *pdev)
 	int irq;
 	struct clk *clk;
 	const struct c_can_driver_data *drvdata;
+	const struct platform_device_id *id;
 	struct device_node *np = pdev->dev.of_node;
 
 	drvdata = device_get_match_data(&pdev->dev);
+	if (!drvdata) {
+		id = platform_get_device_id(pdev);
+		if (!id)
+			return -ENODEV;
+
+		drvdata = (const struct c_can_driver_data *)id->driver_data;
+	}
 
 	/* get the appropriate clk */
 	clk = devm_clk_get(&pdev->dev, NULL);
-- 
2.50.1 (Apple Git-155)