[PATCH v2 1/4] i2c: check bus number property in DesignWare I2C Controller

[Paweł Anikiel]

On SoCFPGA systems, it's desireable to have fixed numbering for
i2c busses, while being able to enable/disable them (e.g. have i2c1
be mapped to /dev/i2c-1, even though i2c0 is disabled). This can also
be achieved using devicetree aliases (see i2c_add_adapter). However,
having the driver be self-contained without relying on aliases is more
robust.

Signed-off-by: Paweł Anikiel <pan@xxxxxxxxxxxx>
---
 drivers/i2c/busses/i2c-designware-platdrv.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 21113665ddea..f27e6bc9ad9d 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -280,7 +280,8 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
 					I2C_CLASS_HWMON : I2C_CLASS_DEPRECATED;
 	ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
 	adap->dev.of_node = pdev->dev.of_node;
-	adap->nr = -1;
+	if (of_property_read_u32(pdev->dev.of_node, "busno", &adap->nr))
+		adap->nr = -1;
 
 	if (dev->flags & ACCESS_NO_IRQ_SUSPEND) {
 		dev_pm_set_driver_flags(&pdev->dev,
-- 
2.25.1