drm/sun4i: add lvds mode_valid function

mode_valid function is missing for lvds.

Add it making it pointed by encoder helper functions.

Signed-off-by: Giulio Benetti <giulio.benetti@micronovasrl.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1520940019-68977-1-git-send-email-giulio.benetti@micronovasrl.com

diff --git a/drivers/gpu/drm/sun4i/sun4i_lvds.c b/drivers/gpu/drm/sun4i/sun4i_lvds.c
index be3f14d..bffff4c 100644 (file)
--- a/drivers/gpu/drm/sun4i/sun4i_lvds.c
+++ b/drivers/gpu/drm/sun4i/sun4i_lvds.c
@@ -94,9 +94,64 @@ static void sun4i_lvds_encoder_disable(struct drm_encoder *encoder)
        }
 }
 
+static enum drm_mode_status sun4i_lvds_encoder_mode_valid(struct drm_encoder *crtc,
+                                                         const struct drm_display_mode *mode)
+{
+       struct sun4i_lvds *lvds = drm_encoder_to_sun4i_lvds(crtc);
+       struct sun4i_tcon *tcon = lvds->tcon;
+       u32 hsync = mode->hsync_end - mode->hsync_start;
+       u32 vsync = mode->vsync_end - mode->vsync_start;
+       unsigned long rate = mode->clock * 1000;
+       long rounded_rate;
+
+       DRM_DEBUG_DRIVER("Validating modes...\n");
+
+       if (hsync < 1)
+               return MODE_HSYNC_NARROW;
+
+       if (hsync > 0x3ff)
+               return MODE_HSYNC_WIDE;
+
+       if ((mode->hdisplay < 1) || (mode->htotal < 1))
+               return MODE_H_ILLEGAL;
+
+       if ((mode->hdisplay > 0x7ff) || (mode->htotal > 0xfff))
+               return MODE_BAD_HVALUE;
+
+       DRM_DEBUG_DRIVER("Horizontal parameters OK\n");
+
+       if (vsync < 1)
+               return MODE_VSYNC_NARROW;
+
+       if (vsync > 0x3ff)
+               return MODE_VSYNC_WIDE;
+
+       if ((mode->vdisplay < 1) || (mode->vtotal < 1))
+               return MODE_V_ILLEGAL;
+
+       if ((mode->vdisplay > 0x7ff) || (mode->vtotal > 0xfff))
+               return MODE_BAD_VVALUE;
+
+       DRM_DEBUG_DRIVER("Vertical parameters OK\n");
+
+       tcon->dclk_min_div = 7;
+       tcon->dclk_max_div = 7;
+       rounded_rate = clk_round_rate(tcon->dclk, rate);
+       if (rounded_rate < rate)
+               return MODE_CLOCK_LOW;
+
+       if (rounded_rate > rate)
+               return MODE_CLOCK_HIGH;
+
+       DRM_DEBUG_DRIVER("Clock rate OK\n");
+
+       return MODE_OK;
+}
+
 static const struct drm_encoder_helper_funcs sun4i_lvds_enc_helper_funcs = {
        .disable        = sun4i_lvds_encoder_disable,
        .enable         = sun4i_lvds_encoder_enable,
+       .mode_valid     = sun4i_lvds_encoder_mode_valid,
 };
 
 static const struct drm_encoder_funcs sun4i_lvds_enc_funcs = {