drm/i915: Include the sink/source/supported rates in debug output

TODO: Is there an actually nice way to print an array of ints?

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Sonika Jindal <sonika.jindal@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 43 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index ce0bdec4b6f9..e2c54912cf11 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1239,6 +1239,46 @@ static int intel_supported_rates(struct intel_dp *intel_dp,
                                supported_rates);
 }
 
+static void snprintf_int_array(char *str, size_t len,
+                               const int *array, int nelem)
+{
+        int i;
+
+        str[0] = '\0';
+
+        for (i = 0; i < nelem; i++) {
+                int r = snprintf(str, len, "%d,", array[i]);
+                if (r >= len)
+                        return;
+                str += r;
+                len -= r;
+        }
+}
+
+static void intel_dp_print_rates(struct intel_dp *intel_dp)
+{
+        struct drm_device *dev = intel_dp_to_dev(intel_dp);
+        const int *source_rates, *sink_rates;
+        int source_len, sink_len, supported_len;
+        int supported_rates[DP_MAX_SUPPORTED_RATES];
+        char str[128]; /* FIXME: too big for stack? */
+
+        if ((drm_debug & DRM_UT_KMS) == 0)
+                return;
+
+        source_len = intel_dp_source_rates(dev, &source_rates);
+        snprintf_int_array(str, sizeof(str), source_rates, source_len);
+        DRM_DEBUG_KMS("source rates: %s\n", str);
+
+        sink_len = intel_dp_sink_rates(intel_dp, &sink_rates);
+        snprintf_int_array(str, sizeof(str), sink_rates, sink_len);
+        DRM_DEBUG_KMS("sink rates: %s\n", str);
+
+        supported_len = intel_supported_rates(intel_dp, supported_rates);
+        snprintf_int_array(str, sizeof(str), supported_rates, supported_len);
+        DRM_DEBUG_KMS("supported rates: %s\n", str);
+}
+
 static int rate_to_index(int find, const int *rates)
 {
         int i = 0;
@@ -3775,6 +3815,9 @@ intel_dp_get_dpcd(struct intel_dp *intel_dp)
                 }
                 intel_dp->num_supported_rates = i;
         }
+
+        intel_dp_print_rates(intel_dp);
+
         if (!(intel_dp->dpcd[DP_DOWNSTREAMPORT_PRESENT] &
               DP_DWN_STRM_PORT_PRESENT))
                 return true; /* native DP sink */