gpu: ipu-di: Add ipu_di_adjust_videomode()

[karo-tx-linux.git] / drivers / gpu / ipu-v3 / ipu-di.c

diff --git a/drivers/gpu/ipu-v3/ipu-di.c b/drivers/gpu/ipu-v3/ipu-di.c
index c490ba4384fc5c0b2f65621d2079a384eb4eba1f..46f9570a8b59ed48b32a4ed89f6febff0429cae1 100644 (file)
--- a/drivers/gpu/ipu-v3/ipu-di.c
+++ b/drivers/gpu/ipu-v3/ipu-di.c
@@ -511,6 +511,35 @@ static void ipu_di_config_clock(struct ipu_di *di,
                clk_get_rate(di->clk_di_pixel) / (clkgen0 >> 4));
 }
 
+/*
+ * This function is called to adjust a video mode to IPU restrictions.
+ * It is meant to be called from drm crtc mode_fixup() methods.
+ */
+int ipu_di_adjust_videomode(struct ipu_di *di, struct videomode *mode)
+{
+       u32 diff;
+
+       if (mode->vfront_porch >= 2)
+               return 0;
+
+       diff = 2 - mode->vfront_porch;
+
+       if (mode->vback_porch >= diff) {
+               mode->vfront_porch = 2;
+               mode->vback_porch -= diff;
+       } else if (mode->vsync_len > diff) {
+               mode->vfront_porch = 2;
+               mode->vsync_len = mode->vsync_len - diff;
+       } else {
+               dev_warn(di->ipu->dev, "failed to adjust videomode\n");
+               return -EINVAL;
+       }
+
+       dev_warn(di->ipu->dev, "videomode adapted for IPU restrictions\n");
+       return 0;
+}
+EXPORT_SYMBOL_GPL(ipu_di_adjust_videomode);
+
 int ipu_di_init_sync_panel(struct ipu_di *di, struct ipu_di_signal_cfg *sig)
 {
        u32 reg;