drm/bridge/sii8620: fix display modes validation

Current implementation of mode_valid() and mode_fixup() callbacks
handle packed pixel modes improperly.

Fix it by using proper maximum clock values from the documentation.

Signed-off-by: Maciej Purski <m.purski@samsung.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1517568865-25219-1-git-send-email-m.purski@samsung.com

1 files changed, 41 insertions, 39 deletions

diff --git a/drivers/gpu/drm/bridge/sil-sii8620.c b/drivers/gpu/drm/bridge/sil-sii8620.c
index 720bc7c325e0..5267dc6551af 100644
--- a/drivers/gpu/drm/bridge/sil-sii8620.c
+++ b/drivers/gpu/drm/bridge/sil-sii8620.c
@@ -36,8 +36,11 @@
 
 #define SII8620_BURST_BUF_LEN 288
 #define VAL_RX_HDMI_CTRL2_DEFVAL VAL_RX_HDMI_CTRL2_IDLE_CNT(3)
-#define MHL1_MAX_LCLK 225000
-#define MHL3_MAX_LCLK 600000
+
+#define MHL1_MAX_PCLK 75000
+#define MHL1_MAX_PCLK_PP_MODE 150000
+#define MHL3_MAX_PCLK 200000
+#define MHL3_MAX_PCLK_PP_MODE 300000
 
 enum sii8620_mode {
         CM_DISCONNECTED,
@@ -2274,17 +2277,43 @@ static void sii8620_detach(struct drm_bridge *bridge)
         rc_unregister_device(ctx->rc_dev);
 }
 
+static int sii8620_is_packing_required(struct sii8620 *ctx,
+                                       const struct drm_display_mode *mode)
+{
+        int max_pclk, max_pclk_pp_mode;
+
+        if (sii8620_is_mhl3(ctx)) {
+                max_pclk = MHL3_MAX_PCLK;
+                max_pclk_pp_mode = MHL3_MAX_PCLK_PP_MODE;
+        } else {
+                max_pclk = MHL1_MAX_PCLK;
+                max_pclk_pp_mode = MHL1_MAX_PCLK_PP_MODE;
+        }
+
+        if (mode->clock < max_pclk)
+                return 0;
+        else if (mode->clock < max_pclk_pp_mode)
+                return 1;
+        else
+                return -1;
+}
+
 static enum drm_mode_status sii8620_mode_valid(struct drm_bridge *bridge,
                                          const struct drm_display_mode *mode)
 {
         struct sii8620 *ctx = bridge_to_sii8620(bridge);
+        int pack_required = sii8620_is_packing_required(ctx, mode);
         bool can_pack = ctx->devcap[MHL_DCAP_VID_LINK_MODE] &
                         MHL_DCAP_VID_LINK_PPIXEL;
-        unsigned int max_pclk = sii8620_is_mhl3(ctx) ? MHL3_MAX_LCLK :
-                                                       MHL1_MAX_LCLK;
-        max_pclk /= can_pack ? 2 : 3;
 
-        return (mode->clock > max_pclk) ? MODE_CLOCK_HIGH : MODE_OK;
+        switch (pack_required) {
+        case 0:
+                return MODE_OK;
+        case 1:
+                return (can_pack) ? MODE_OK : MODE_CLOCK_HIGH;
+        default:
+                return MODE_CLOCK_HIGH;
+        }
 }
 
 static bool sii8620_mode_fixup(struct drm_bridge *bridge,
@@ -2292,43 +2321,16 @@ static bool sii8620_mode_fixup(struct drm_bridge *bridge,
                                struct drm_display_mode *adjusted_mode)
 {
         struct sii8620 *ctx = bridge_to_sii8620(bridge);
-        int max_lclk;
-        bool ret = true;
 
         mutex_lock(&ctx->lock);
 
-        max_lclk = sii8620_is_mhl3(ctx) ? MHL3_MAX_LCLK : MHL1_MAX_LCLK;
-        if (max_lclk > 3 * adjusted_mode->clock) {
-                ctx->use_packed_pixel = 0;
-                goto end;
-        }
-        if ((ctx->devcap[MHL_DCAP_VID_LINK_MODE] & MHL_DCAP_VID_LINK_PPIXEL) &&
-            max_lclk > 2 * adjusted_mode->clock) {
-                ctx->use_packed_pixel = 1;
-                goto end;
-        }
-        ret = false;
-end:
-        if (ret) {
-                u8 vic = drm_match_cea_mode(adjusted_mode);
-
-                if (!vic) {
-                        union hdmi_infoframe frm;
-                        u8 mhl_vic[] = { 0, 95, 94, 93, 98 };
-
-                        /* FIXME: We need the connector here */
-                        drm_hdmi_vendor_infoframe_from_display_mode(
-                                &frm.vendor.hdmi, NULL, adjusted_mode);
-                        vic = frm.vendor.hdmi.vic;
-                        if (vic >= ARRAY_SIZE(mhl_vic))
-                                vic = 0;
-                        vic = mhl_vic[vic];
-                }
-                ctx->video_code = vic;
-                ctx->pixel_clock = adjusted_mode->clock;
-        }
+        ctx->use_packed_pixel = sii8620_is_packing_required(ctx, adjusted_mode);
+        ctx->video_code = drm_match_cea_mode(adjusted_mode);
+        ctx->pixel_clock = adjusted_mode->clock;
+
         mutex_unlock(&ctx->lock);
-        return ret;
+
+        return true;
 }
 
 static const struct drm_bridge_funcs sii8620_bridge_funcs = {