diff mbox series

[PATCHv2,2/4] Input: rotary-encoder - Fix steps property reading

Message ID 20200907204045.95530-3-sebastian.reichel@collabora.com (mailing list archive)
State New, archived
Headers show
Series Rotary Encoder Push Button Support | expand

Commit Message

Sebastian Reichel Sept. 7, 2020, 8:40 p.m. UTC
The DT binding specifies 24 being used by default, but driver
initializes to 0. The steps variable will be used for a modulo
operation at a later step, so do not allow 0 (does not make
sense in any case).

Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
---
 drivers/input/misc/rotary_encoder.c | 5 +++++
 1 file changed, 5 insertions(+)
diff mbox series

Patch

diff --git a/drivers/input/misc/rotary_encoder.c b/drivers/input/misc/rotary_encoder.c
index 6d613f2a017c..e9a5dbb10513 100644
--- a/drivers/input/misc/rotary_encoder.c
+++ b/drivers/input/misc/rotary_encoder.c
@@ -198,7 +198,12 @@  static int rotary_encoder_probe(struct platform_device *pdev)
 
 	mutex_init(&encoder->access_mutex);
 
+	encoder->steps = 24;
 	device_property_read_u32(dev, "rotary-encoder,steps", &encoder->steps);
+	if (!encoder->steps) {
+		dev_err(dev, "invalid steps setting\n");
+		return -EINVAL;
+	}
 
 	err = device_property_read_u32(dev, "rotary-encoder,steps-per-period",
 				       &steps_per_period);