[PATCH v2] thermal: Add some error messages

[Amit Kucheria <amit.kucheria@linaro.org>]

When registering a thermal zone device, we currently return -EINVAL in
four cases. This makes it a little hard to debug the real cause of the
failure.

Print some error messages to make it easier for developer to figure out
what happened.

Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
---
 drivers/thermal/thermal_core.c | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index 46cfb7de4eb2..e1c2c2638219 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -1238,17 +1238,26 @@ thermal_zone_device_register(const char *type, int trips, int mask,
 	int count;
 	struct thermal_governor *governor;
 
-	if (!type || strlen(type) == 0)
+	if (!type || strlen(type) == 0) {
+		pr_err("Error: No thermal zone type defined\n");
 		return ERR_PTR(-EINVAL);
+	}
 
-	if (type && strlen(type) >= THERMAL_NAME_LENGTH)
+	if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
+		pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
+		       type, THERMAL_NAME_LENGTH);
 		return ERR_PTR(-EINVAL);
+	}
 
-	if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips)
+	if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
+		pr_err("Error: Incorrect number of thermal trips\n");
 		return ERR_PTR(-EINVAL);
+	}
 
-	if (!ops)
+	if (!ops) {
+		pr_err("Error: Thermal zone device ops not defined\n");
 		return ERR_PTR(-EINVAL);
+	}
 
 	if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
 		return ERR_PTR(-EINVAL);
-- 
2.17.1