drm/i915/mst: change return value of mst_stream_find_vcpi_slots_for_bpp()

The callers of mst_stream_find_vcpi_slots_for_bpp() don't need the
returned slots for anything. On the contrary, they need to jump through
hoops to just distinguish between success and failure. Just return 0
instead of slots from mst_stream_find_vcpi_slots_for_bpp() for success,
and simplify the callers.

There's a pointless ret local variable that we can drop in the process.

Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/7b3671a548c893b1bb62151d41f90bb8ce842ccc.1735912293.git.jani.nikula@intel.com

diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
index 927b0f05a691ebdc8d47c92f46c3dc8f1e1a14de..f1adb1d0ecb389b27c3589e357a822072ce9eb2d 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
@@ -226,7 +226,6 @@ static int mst_stream_find_vcpi_slots_for_bpp(struct intel_dp *intel_dp,
        int bpp, slots = -EINVAL;
        int dsc_slice_count = 0;
        int max_dpt_bpp;
-       int ret = 0;
 
        mst_state = drm_atomic_get_mst_topology_state(state, &intel_dp->mst_mgr);
        if (IS_ERR(mst_state))
@@ -340,23 +339,21 @@ static int mst_stream_find_vcpi_slots_for_bpp(struct intel_dp *intel_dp,
                }
        }
 
-       /* We failed to find a proper bpp/timeslots, return error */
-       if (ret)
-               slots = ret;
-
        if (slots < 0) {
                drm_dbg_kms(display->drm, "failed finding vcpi slots:%d\n",
                            slots);
-       } else {
-               if (!dsc)
-                       crtc_state->pipe_bpp = bpp;
-               else
-                       crtc_state->dsc.compressed_bpp_x16 = fxp_q4_from_int(bpp);
-               drm_dbg_kms(display->drm, "Got %d slots for pipe bpp %d dsc %d\n",
-                           slots, bpp, dsc);
+               return slots;
        }
 
-       return slots;
+       if (!dsc)
+               crtc_state->pipe_bpp = bpp;
+       else
+               crtc_state->dsc.compressed_bpp_x16 = fxp_q4_from_int(bpp);
+
+       drm_dbg_kms(display->drm, "Got %d slots for pipe bpp %d dsc %d\n",
+                   slots, bpp, dsc);
+
+       return 0;
 }
 
 static int mst_stream_compute_link_config(struct intel_dp *intel_dp,
@@ -364,22 +361,15 @@ static int mst_stream_compute_link_config(struct intel_dp *intel_dp,
                                          struct drm_connector_state *conn_state,
                                          struct link_config_limits *limits)
 {
-       int slots = -EINVAL;
-
        /*
         * FIXME: allocate the BW according to link_bpp, which in the case of
         * YUV420 is only half of the pipe bpp value.
         */
-       slots = mst_stream_find_vcpi_slots_for_bpp(intel_dp, crtc_state,
-                                                  fxp_q4_to_int(limits->link.max_bpp_x16),
-                                                  fxp_q4_to_int(limits->link.min_bpp_x16),
-                                                  limits,
-                                                  conn_state, 2 * 3, false);
-
-       if (slots < 0)
-               return slots;
-
-       return 0;
+       return mst_stream_find_vcpi_slots_for_bpp(intel_dp, crtc_state,
+                                                 fxp_q4_to_int(limits->link.max_bpp_x16),
+                                                 fxp_q4_to_int(limits->link.min_bpp_x16),
+                                                 limits,
+                                                 conn_state, 2 * 3, false);
 }
 
 static int mst_stream_dsc_compute_link_config(struct intel_dp *intel_dp,
@@ -389,7 +379,6 @@ static int mst_stream_dsc_compute_link_config(struct intel_dp *intel_dp,
 {
        struct intel_display *display = to_intel_display(intel_dp);
        struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       int slots = -EINVAL;
        int i, num_bpc;
        u8 dsc_bpc[3] = {};
        int min_bpp, max_bpp, sink_min_bpp, sink_max_bpp;
@@ -437,14 +426,9 @@ static int mst_stream_dsc_compute_link_config(struct intel_dp *intel_dp,
        min_compressed_bpp = intel_dp_dsc_nearest_valid_bpp(display, min_compressed_bpp,
                                                            crtc_state->pipe_bpp);
 
-       slots = mst_stream_find_vcpi_slots_for_bpp(intel_dp, crtc_state, max_compressed_bpp,
-                                                  min_compressed_bpp, limits,
-                                                  conn_state, 1, true);
-
-       if (slots < 0)
-               return slots;
-
-       return 0;
+       return mst_stream_find_vcpi_slots_for_bpp(intel_dp, crtc_state, max_compressed_bpp,
+                                                 min_compressed_bpp, limits,
+                                                 conn_state, 1, true);
 }
 
 static int mst_stream_update_slots(struct intel_dp *intel_dp,