drm/i915/perf: remove user triggerable warn

Don't throw a warning if we are given an invalid property id. While
here let's also bring back Robert' original idea of catching unhandled
enumeration values at compile time.

Fixes: eec688e1420d ("drm/i915: Add i915 perf infrastructure")
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Robert Bragg <robert@sixbynine.org>
Reviewed-by: Robert Bragg <robert@sixbynine.org>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170327203236.18276-1-matthew.auld@intel.com
(cherry picked from commit 0a309f9e3dfaa4f5db0bf1b0cab54571744b491a)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

1 files changed, 6 insertions, 2 deletions

diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index f8fcb317042e..70964ca9251e 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -1794,6 +1794,11 @@ static int read_properties_unlocked(struct drm_i915_private *dev_priv,
                 if (ret)
                         return ret;
 
+                if (id == 0 || id >= DRM_I915_PERF_PROP_MAX) {
+                        DRM_DEBUG("Unknown i915 perf property ID\n");
+                        return -EINVAL;
+                }
+
                 switch ((enum drm_i915_perf_property_id)id) {
                 case DRM_I915_PERF_PROP_CTX_HANDLE:
                         props->single_context = 1;
@@ -1863,9 +1868,8 @@ static int read_properties_unlocked(struct drm_i915_private *dev_priv,
                         props->oa_periodic = true;
                         props->oa_period_exponent = value;
                         break;
-                default:
+                case DRM_I915_PERF_PROP_MAX:
                         MISSING_CASE(id);
-                        DRM_DEBUG("Unknown i915 perf property ID\n");
                         return -EINVAL;
                 }