disp: msm: sde: Register LUTDMA dummy region after parameter validation

A dummy LUTDMA region is registered prior to parameter validation, potentially
causing the usage of an unallocated memory if the sde_mdss_cfg structure is
invalid. Update the code flow so that the dummy LUTDMA region is registered after
all parameter validation

Change-Id: I9a10b166ee7a611b9d5d2cb0555822996d123c10
Signed-off-by: Christopher Braga <[email protected]>

msm/sde/sde_reg_dma.c

@@ -122,6 +122,12 @@ int sde_reg_dma_init(void __iomem *addr, struct sde_mdss_cfg *m,
 
 	set_default_dma_ops(&reg_dma);
 
+	if (!addr || !m || !dev) {
+		DRM_DEBUG("invalid addr %pK catalog %pK dev %pK\n", addr, m,
+				dev);
+		return 0;
+	}
+
 	/**
 	 * Register dummy range to ensure register dump is only done on
 	 * targeted LUTDMA regions. start = 1, end = 1 so full range isn't used
@@ -129,12 +135,6 @@ int sde_reg_dma_init(void __iomem *addr, struct sde_mdss_cfg *m,
 	sde_dbg_reg_register_dump_range(LUTDMA_DBG_NAME, "DUMMY_LUTDMA", 1, 1,
 			m->dma_cfg.xin_id);
 
-	if (!addr || !m || !dev) {
-		DRM_DEBUG("invalid addr %pK catalog %pK dev %pK\n", addr, m,
-				dev);
-		return 0;
-	}
-
 	if (!m->reg_dma_count)
 		return 0;