drm/i915: always return something on DDI clock selection

Even if we don't have the correct clock and get a warning, we should not
skip the return.

v2: improve commit message (from Joonas)

Fixes: c57347e38f1c ("drm/i915/icl: start adding the TBT pll")
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: <stable@vger.kernel.org> # v4.19+
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Mika Kahola <mika.kahola@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190125222444.19926-3-lucas.demarchi@intel.com
(cherry picked from commit 7a61a6dec3dfb9f2e8c39a337580a3c3036c5cdf)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index f3e1d6a0b7dda7cabb0cc882e40aecbd83a1501c..4079050f9d6c81e485706910d58a8494a3e0c2aa 100644 (file)
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -1086,7 +1086,7 @@ static uint32_t icl_pll_to_ddi_pll_sel(struct intel_encoder *encoder,
                        return DDI_CLK_SEL_TBT_810;
                default:
                        MISSING_CASE(clock);
-                       break;
+                       return DDI_CLK_SEL_NONE;
                }
        case DPLL_ID_ICL_MGPLL1:
        case DPLL_ID_ICL_MGPLL2: