[PATCH v3 12/19] HID: logitech-hidpp: return an error if the queried feature is not present

From: Benjamin Tissoires
Date: Mon Mar 27 2017 - 11:04:32 EST


Or the device just answers a valid feature '0'.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>

---

changes in v3:
- moved up in the series

no changes in v2
---
drivers/hid/hid-logitech-hidpp.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c
index 9a9771a..22129dd 100644
--- a/drivers/hid/hid-logitech-hidpp.c
+++ b/drivers/hid/hid-logitech-hidpp.c
@@ -503,6 +503,9 @@ static int hidpp_root_get_feature(struct hidpp_device *hidpp, u16 feature,
if (ret)
return ret;

+ if (response.fap.params[0] == 0)
+ return -ENOENT;
+
*feature_index = response.fap.params[0];
*feature_type = response.fap.params[1];

--
2.9.3