drm/i915/alpm: Remove error handling from get_lfps_cycle_min_max_time

Getter for LFPS cycle min/max times is unnecessarily checking faulty port
clock value. This doesn't make sense as erroneous port clock value would
have been noticed already at this point. Remove this check and use 140/800
ns always when port clock > 540000.

Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
Reviewed-by: Mika Kahola <mika.kahola@intel.com>
Link: https://lore.kernel.org/r/20250912064035.335329-1-jouni.hogander@intel.com

diff --git a/drivers/gpu/drm/i915/display/intel_alpm.c b/drivers/gpu/drm/i915/display/intel_alpm.c
index ed7a7ed486b55b6ca97af3c25cb2118b9af42923..749119cc0b280e8463047dd500f46198065a563b 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_alpm.c
+++ b/drivers/gpu/drm/i915/display/intel_alpm.c
@@ -58,43 +58,32 @@ static int get_silence_period_symbols(const struct intel_crtc_state *crtc_state)
                1000 / 1000;
 }
 
-static int get_lfps_cycle_min_max_time(const struct intel_crtc_state *crtc_state,
-                                      int *min, int *max)
+static void get_lfps_cycle_min_max_time(const struct intel_crtc_state *crtc_state,
+                                       int *min, int *max)
 {
        if (crtc_state->port_clock < 540000) {
                *min = 65 * LFPS_CYCLE_COUNT;
                *max = 75 * LFPS_CYCLE_COUNT;
-       } else if (crtc_state->port_clock <= 810000) {
+       } else {
                *min = 140;
                *max = 800;
-       } else {
-               *min = *max = -1;
-               return -1;
        }
-
-       return 0;
 }
 
 static int get_lfps_cycle_time(const struct intel_crtc_state *crtc_state)
 {
-       int tlfps_cycle_min, tlfps_cycle_max, ret;
+       int tlfps_cycle_min, tlfps_cycle_max;
 
-       ret = get_lfps_cycle_min_max_time(crtc_state, &tlfps_cycle_min,
-                                         &tlfps_cycle_max);
-       if (ret)
-               return ret;
+       get_lfps_cycle_min_max_time(crtc_state, &tlfps_cycle_min,
+                                   &tlfps_cycle_max);
 
        return tlfps_cycle_min +  (tlfps_cycle_max - tlfps_cycle_min) / 2;
 }
 
 static int get_lfps_half_cycle_clocks(const struct intel_crtc_state *crtc_state)
 {
-       int lfps_cycle_time = get_lfps_cycle_time(crtc_state);
-
-       if (lfps_cycle_time < 0)
-               return -1;
-
-       return lfps_cycle_time * crtc_state->port_clock / 1000 / 1000 / (2 * LFPS_CYCLE_COUNT);
+       return get_lfps_cycle_time(crtc_state) * crtc_state->port_clock / 1000 /
+               1000 / (2 * LFPS_CYCLE_COUNT);
 }
 
 /*
@@ -146,8 +135,6 @@ _lnl_compute_aux_less_alpm_params(struct intel_dp *intel_dp,
        silence_period = get_silence_period_symbols(crtc_state);
 
        lfps_half_cycle = get_lfps_half_cycle_clocks(crtc_state);
-       if (lfps_half_cycle < 0)
-               return false;
 
        if (aux_less_wake_lines > ALPM_CTL_AUX_LESS_WAKE_TIME_MASK ||
            silence_period > PORT_ALPM_CTL_SILENCE_PERIOD_MASK ||