Merge tag 'mediatek-drm-fixes-20260119' of https://git.kernel.org/pub/scm/linux/kernel/git/chunkuang.hu/linux into drm-fixes

Mediatek DRM Fixes - 20260119

1. Fix platform_get_irq() error checking
2. HDMI DDC v2 driver fixes
3. dpi: Find next bridge during probe
4. mtk_gem: Partial refactor and use drm_gem_dma_object
5. dt-bindings: Fix typo 'hardwares' to 'hardware'

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Chun-Kuang Hu <chunkuang.hu@kernel.org>
Link: https://patch.msgid.link/20260119154717.4735-1-chunkuang.hu@kernel.org

9 files changed, 157 insertions, 242 deletions

diff --git a/drivers/gpu/drm/mediatek/Kconfig b/drivers/gpu/drm/mediatek/Kconfig
index 96188bf9274a..ad8c8b823681 100644
--- a/drivers/gpu/drm/mediatek/Kconfig
+++ b/drivers/gpu/drm/mediatek/Kconfig
@@ -8,7 +8,7 @@ config DRM_MEDIATEK
 	depends on OF
 	depends on MTK_MMSYS
 	select DRM_CLIENT_SELECTION
-	select DRM_GEM_DMA_HELPER if DRM_FBDEV_EMULATION
+	select DRM_GEM_DMA_HELPER
 	select DRM_KMS_HELPER
 	select DRM_DISPLAY_HELPER
 	select DRM_BRIDGE_CONNECTOR
diff --git a/drivers/gpu/drm/mediatek/mtk_dpi.c b/drivers/gpu/drm/mediatek/mtk_dpi.c
index 61cab32e213a..53360b5d12ba 100644
--- a/drivers/gpu/drm/mediatek/mtk_dpi.c
+++ b/drivers/gpu/drm/mediatek/mtk_dpi.c
@@ -836,20 +836,6 @@ static int mtk_dpi_bridge_attach(struct drm_bridge *bridge,
 				 enum drm_bridge_attach_flags flags)
 {
 	struct mtk_dpi *dpi = bridge_to_dpi(bridge);
-	int ret;
-
-	dpi->next_bridge = devm_drm_of_get_bridge(dpi->dev, dpi->dev->of_node, 1, -1);
-	if (IS_ERR(dpi->next_bridge)) {
-		ret = PTR_ERR(dpi->next_bridge);
-		if (ret == -EPROBE_DEFER)
-			return ret;
-
-		/* Old devicetree has only one endpoint */
-		dpi->next_bridge = devm_drm_of_get_bridge(dpi->dev, dpi->dev->of_node, 0, 0);
-		if (IS_ERR(dpi->next_bridge))
-			return dev_err_probe(dpi->dev, PTR_ERR(dpi->next_bridge),
-					     "Failed to get bridge\n");
-	}
 
 	return drm_bridge_attach(encoder, dpi->next_bridge,
 				 &dpi->bridge, flags);
@@ -1319,6 +1305,15 @@ static int mtk_dpi_probe(struct platform_device *pdev)
 	if (dpi->irq < 0)
 		return dpi->irq;
 
+	dpi->next_bridge = devm_drm_of_get_bridge(dpi->dev, dpi->dev->of_node, 1, -1);
+	if (IS_ERR(dpi->next_bridge) && PTR_ERR(dpi->next_bridge) == -ENODEV) {
+		/* Old devicetree has only one endpoint */
+		dpi->next_bridge = devm_drm_of_get_bridge(dpi->dev, dpi->dev->of_node, 0, 0);
+	}
+	if (IS_ERR(dpi->next_bridge))
+		return dev_err_probe(dpi->dev, PTR_ERR(dpi->next_bridge),
+				     "Failed to get bridge\n");
+
 	platform_set_drvdata(pdev, dpi);
 
 	dpi->bridge.of_node = dev->of_node;
diff --git a/drivers/gpu/drm/mediatek/mtk_gem.c b/drivers/gpu/drm/mediatek/mtk_gem.c
index 024cc7e9036c..7525a9f9907a 100644
--- a/drivers/gpu/drm/mediatek/mtk_gem.c
+++ b/drivers/gpu/drm/mediatek/mtk_gem.c
@@ -1,6 +1,8 @@
 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (c) 2015 MediaTek Inc.
+ * Copyright (c) 2025 Collabora Ltd.
+ *                    AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
  */
 
 #include <linux/dma-buf.h>
@@ -18,24 +20,64 @@
 
 static int mtk_gem_object_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma);
 
-static const struct vm_operations_struct vm_ops = {
-	.open = drm_gem_vm_open,
-	.close = drm_gem_vm_close,
-};
+static void mtk_gem_free_object(struct drm_gem_object *obj)
+{
+	struct drm_gem_dma_object *dma_obj = to_drm_gem_dma_obj(obj);
+	struct mtk_drm_private *priv = obj->dev->dev_private;
+
+	if (dma_obj->sgt)
+		drm_prime_gem_destroy(obj, dma_obj->sgt);
+	else
+		dma_free_wc(priv->dma_dev, dma_obj->base.size,
+			    dma_obj->vaddr, dma_obj->dma_addr);
+
+	/* release file pointer to gem object. */
+	drm_gem_object_release(obj);
+
+	kfree(dma_obj);
+}
+
+/*
+ * Allocate a sg_table for this GEM object.
+ * Note: Both the table's contents, and the sg_table itself must be freed by
+ *       the caller.
+ * Returns a pointer to the newly allocated sg_table, or an ERR_PTR() error.
+ */
+static struct sg_table *mtk_gem_prime_get_sg_table(struct drm_gem_object *obj)
+{
+	struct drm_gem_dma_object *dma_obj = to_drm_gem_dma_obj(obj);
+	struct mtk_drm_private *priv = obj->dev->dev_private;
+	struct sg_table *sgt;
+	int ret;
+
+	sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
+	if (!sgt)
+		return ERR_PTR(-ENOMEM);
+
+	ret = dma_get_sgtable(priv->dma_dev, sgt, dma_obj->vaddr,
+			      dma_obj->dma_addr, obj->size);
+	if (ret) {
+		DRM_ERROR("failed to allocate sgt, %d\n", ret);
+		kfree(sgt);
+		return ERR_PTR(ret);
+	}
+
+	return sgt;
+}
 
 static const struct drm_gem_object_funcs mtk_gem_object_funcs = {
 	.free = mtk_gem_free_object,
+	.print_info = drm_gem_dma_object_print_info,
 	.get_sg_table = mtk_gem_prime_get_sg_table,
-	.vmap = mtk_gem_prime_vmap,
-	.vunmap = mtk_gem_prime_vunmap,
+	.vmap = drm_gem_dma_object_vmap,
 	.mmap = mtk_gem_object_mmap,
-	.vm_ops = &vm_ops,
+	.vm_ops = &drm_gem_dma_vm_ops,
 };
 
-static struct mtk_gem_obj *mtk_gem_init(struct drm_device *dev,
-					unsigned long size)
+static struct drm_gem_dma_object *mtk_gem_init(struct drm_device *dev,
+					unsigned long size, bool private)
 {
-	struct mtk_gem_obj *mtk_gem_obj;
+	struct drm_gem_dma_object *dma_obj;
 	int ret;
 
 	size = round_up(size, PAGE_SIZE);
@@ -43,86 +85,65 @@ static struct mtk_gem_obj *mtk_gem_init(struct drm_device *dev,
 	if (size == 0)
 		return ERR_PTR(-EINVAL);
 
-	mtk_gem_obj = kzalloc(sizeof(*mtk_gem_obj), GFP_KERNEL);
-	if (!mtk_gem_obj)
+	dma_obj = kzalloc(sizeof(*dma_obj), GFP_KERNEL);
+	if (!dma_obj)
 		return ERR_PTR(-ENOMEM);
 
-	mtk_gem_obj->base.funcs = &mtk_gem_object_funcs;
+	dma_obj->base.funcs = &mtk_gem_object_funcs;
 
-	ret = drm_gem_object_init(dev, &mtk_gem_obj->base, size);
-	if (ret < 0) {
+	if (private) {
+		ret = 0;
+		drm_gem_private_object_init(dev, &dma_obj->base, size);
+	} else {
+		ret = drm_gem_object_init(dev, &dma_obj->base, size);
+	}
+	if (ret) {
 		DRM_ERROR("failed to initialize gem object\n");
-		kfree(mtk_gem_obj);
+		kfree(dma_obj);
 		return ERR_PTR(ret);
 	}
 
-	return mtk_gem_obj;
+	return dma_obj;
 }
 
-struct mtk_gem_obj *mtk_gem_create(struct drm_device *dev,
-				   size_t size, bool alloc_kmap)
+static struct drm_gem_dma_object *mtk_gem_create(struct drm_device *dev, size_t size)
 {
 	struct mtk_drm_private *priv = dev->dev_private;
-	struct mtk_gem_obj *mtk_gem;
+	struct drm_gem_dma_object *dma_obj;
 	struct drm_gem_object *obj;
 	int ret;
 
-	mtk_gem = mtk_gem_init(dev, size);
-	if (IS_ERR(mtk_gem))
-		return ERR_CAST(mtk_gem);
-
-	obj = &mtk_gem->base;
+	dma_obj = mtk_gem_init(dev, size, false);
+	if (IS_ERR(dma_obj))
+		return ERR_CAST(dma_obj);
 
-	mtk_gem->dma_attrs = DMA_ATTR_WRITE_COMBINE;
+	obj = &dma_obj->base;
 
-	if (!alloc_kmap)
-		mtk_gem->dma_attrs |= DMA_ATTR_NO_KERNEL_MAPPING;
-
-	mtk_gem->cookie = dma_alloc_attrs(priv->dma_dev, obj->size,
-					  &mtk_gem->dma_addr, GFP_KERNEL,
-					  mtk_gem->dma_attrs);
-	if (!mtk_gem->cookie) {
+	dma_obj->vaddr = dma_alloc_wc(priv->dma_dev, obj->size,
+				      &dma_obj->dma_addr,
+				      GFP_KERNEL | __GFP_NOWARN);
+	if (!dma_obj->vaddr) {
 		DRM_ERROR("failed to allocate %zx byte dma buffer", obj->size);
 		ret = -ENOMEM;
 		goto err_gem_free;
 	}
 
-	if (alloc_kmap)
-		mtk_gem->kvaddr = mtk_gem->cookie;
-
-	DRM_DEBUG_DRIVER("cookie = %p dma_addr = %pad size = %zu\n",
-			 mtk_gem->cookie, &mtk_gem->dma_addr,
+	DRM_DEBUG_DRIVER("vaddr = %p dma_addr = %pad size = %zu\n",
+			 dma_obj->vaddr, &dma_obj->dma_addr,
 			 size);
 
-	return mtk_gem;
+	return dma_obj;
 
 err_gem_free:
 	drm_gem_object_release(obj);
-	kfree(mtk_gem);
+	kfree(dma_obj);
 	return ERR_PTR(ret);
 }
 
-void mtk_gem_free_object(struct drm_gem_object *obj)
-{
-	struct mtk_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
-	struct mtk_drm_private *priv = obj->dev->dev_private;
-
-	if (mtk_gem->sg)
-		drm_prime_gem_destroy(obj, mtk_gem->sg);
-	else
-		dma_free_attrs(priv->dma_dev, obj->size, mtk_gem->cookie,
-			       mtk_gem->dma_addr, mtk_gem->dma_attrs);
-
-	/* release file pointer to gem object. */
-	drm_gem_object_release(obj);
-
-	kfree(mtk_gem);
-}
-
 int mtk_gem_dumb_create(struct drm_file *file_priv, struct drm_device *dev,
 			struct drm_mode_create_dumb *args)
 {
-	struct mtk_gem_obj *mtk_gem;
+	struct drm_gem_dma_object *dma_obj;
 	int ret;
 
 	args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
@@ -135,25 +156,25 @@ int mtk_gem_dumb_create(struct drm_file *file_priv, struct drm_device *dev,
 	args->size = args->pitch;
 	args->size *= args->height;
 
-	mtk_gem = mtk_gem_create(dev, args->size, false);
-	if (IS_ERR(mtk_gem))
-		return PTR_ERR(mtk_gem);
+	dma_obj = mtk_gem_create(dev, args->size);
+	if (IS_ERR(dma_obj))
+		return PTR_ERR(dma_obj);
 
 	/*
 	 * allocate a id of idr table where the obj is registered
 	 * and handle has the id what user can see.
 	 */
-	ret = drm_gem_handle_create(file_priv, &mtk_gem->base, &args->handle);
+	ret = drm_gem_handle_create(file_priv, &dma_obj->base, &args->handle);
 	if (ret)
 		goto err_handle_create;
 
 	/* drop reference from allocate - handle holds it now. */
-	drm_gem_object_put(&mtk_gem->base);
+	drm_gem_object_put(&dma_obj->base);
 
 	return 0;
 
 err_handle_create:
-	mtk_gem_free_object(&mtk_gem->base);
+	mtk_gem_free_object(&dma_obj->base);
 	return ret;
 }
 
@@ -161,129 +182,50 @@ static int mtk_gem_object_mmap(struct drm_gem_object *obj,
 			       struct vm_area_struct *vma)
 
 {
-	int ret;
-	struct mtk_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
+	struct drm_gem_dma_object *dma_obj = to_drm_gem_dma_obj(obj);
 	struct mtk_drm_private *priv = obj->dev->dev_private;
+	int ret;
 
 	/*
 	 * Set vm_pgoff (used as a fake buffer offset by DRM) to 0 and map the
 	 * whole buffer from the start.
 	 */
-	vma->vm_pgoff = 0;
+	vma->vm_pgoff -= drm_vma_node_start(&obj->vma_node);
 
 	/*
 	 * dma_alloc_attrs() allocated a struct page table for mtk_gem, so clear
 	 * VM_PFNMAP flag that was set by drm_gem_mmap_obj()/drm_gem_mmap().
 	 */
-	vm_flags_set(vma, VM_IO | VM_DONTEXPAND | VM_DONTDUMP);
+	vm_flags_mod(vma, VM_IO | VM_DONTEXPAND | VM_DONTDUMP, VM_PFNMAP);
+
 	vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
 	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
 
-	ret = dma_mmap_attrs(priv->dma_dev, vma, mtk_gem->cookie,
-			     mtk_gem->dma_addr, obj->size, mtk_gem->dma_attrs);
+	ret = dma_mmap_wc(priv->dma_dev, vma, dma_obj->vaddr,
+			  dma_obj->dma_addr, obj->size);
+	if (ret)
+		drm_gem_vm_close(vma);
 
 	return ret;
 }
 
-/*
- * Allocate a sg_table for this GEM object.
- * Note: Both the table's contents, and the sg_table itself must be freed by
- *       the caller.
- * Returns a pointer to the newly allocated sg_table, or an ERR_PTR() error.
- */
-struct sg_table *mtk_gem_prime_get_sg_table(struct drm_gem_object *obj)
-{
-	struct mtk_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
-	struct mtk_drm_private *priv = obj->dev->dev_private;
-	struct sg_table *sgt;
-	int ret;
-
-	sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
-	if (!sgt)
-		return ERR_PTR(-ENOMEM);
-
-	ret = dma_get_sgtable_attrs(priv->dma_dev, sgt, mtk_gem->cookie,
-				    mtk_gem->dma_addr, obj->size,
-				    mtk_gem->dma_attrs);
-	if (ret) {
-		DRM_ERROR("failed to allocate sgt, %d\n", ret);
-		kfree(sgt);
-		return ERR_PTR(ret);
-	}
-
-	return sgt;
-}
-
 struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev,
-			struct dma_buf_attachment *attach, struct sg_table *sg)
+			struct dma_buf_attachment *attach, struct sg_table *sgt)
 {
-	struct mtk_gem_obj *mtk_gem;
+	struct drm_gem_dma_object *dma_obj;
 
 	/* check if the entries in the sg_table are contiguous */
-	if (drm_prime_get_contiguous_size(sg) < attach->dmabuf->size) {
+	if (drm_prime_get_contiguous_size(sgt) < attach->dmabuf->size) {
 		DRM_ERROR("sg_table is not contiguous");
 		return ERR_PTR(-EINVAL);
 	}
 
-	mtk_gem = mtk_gem_init(dev, attach->dmabuf->size);
-	if (IS_ERR(mtk_gem))
-		return ERR_CAST(mtk_gem);
-
-	mtk_gem->dma_addr = sg_dma_address(sg->sgl);
-	mtk_gem->sg = sg;
-
-	return &mtk_gem->base;
-}
-
-int mtk_gem_prime_vmap(struct drm_gem_object *obj, struct iosys_map *map)
-{
-	struct mtk_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
-	struct sg_table *sgt = NULL;
-	unsigned int npages;
-
-	if (mtk_gem->kvaddr)
-		goto out;
-
-	sgt = mtk_gem_prime_get_sg_table(obj);
-	if (IS_ERR(sgt))
-		return PTR_ERR(sgt);
-
-	npages = obj->size >> PAGE_SHIFT;
-	mtk_gem->pages = kcalloc(npages, sizeof(*mtk_gem->pages), GFP_KERNEL);
-	if (!mtk_gem->pages) {
-		sg_free_table(sgt);
-		kfree(sgt);
-		return -ENOMEM;
-	}
-
-	drm_prime_sg_to_page_array(sgt, mtk_gem->pages, npages);
-
-	mtk_gem->kvaddr = vmap(mtk_gem->pages, npages, VM_MAP,
-			       pgprot_writecombine(PAGE_KERNEL));
-	if (!mtk_gem->kvaddr) {
-		sg_free_table(sgt);
-		kfree(sgt);
-		kfree(mtk_gem->pages);
-		return -ENOMEM;
-	}
-	sg_free_table(sgt);
-	kfree(sgt);
-
-out:
-	iosys_map_set_vaddr(map, mtk_gem->kvaddr);
-
-	return 0;
-}
-
-void mtk_gem_prime_vunmap(struct drm_gem_object *obj, struct iosys_map *map)
-{
-	struct mtk_gem_obj *mtk_gem = to_mtk_gem_obj(obj);
-	void *vaddr = map->vaddr;
+	dma_obj = mtk_gem_init(dev, attach->dmabuf->size, true);
+	if (IS_ERR(dma_obj))
+		return ERR_CAST(dma_obj);
 
-	if (!mtk_gem->pages)
-		return;
+	dma_obj->dma_addr = sg_dma_address(sgt->sgl);
+	dma_obj->sgt = sgt;
 
-	vunmap(vaddr);
-	mtk_gem->kvaddr = NULL;
-	kfree(mtk_gem->pages);
+	return &dma_obj->base;
 }
diff --git a/drivers/gpu/drm/mediatek/mtk_gem.h b/drivers/gpu/drm/mediatek/mtk_gem.h
index 66e5f154f698..afebc3a970a8 100644
--- a/drivers/gpu/drm/mediatek/mtk_gem.h
+++ b/drivers/gpu/drm/mediatek/mtk_gem.h
@@ -7,42 +7,11 @@
 #define _MTK_GEM_H_
 
 #include <drm/drm_gem.h>
+#include <drm/drm_gem_dma_helper.h>
 
-/*
- * mtk drm buffer structure.
- *
- * @base: a gem object.
- *	- a new handle to this gem object would be created
- *	by drm_gem_handle_create().
- * @cookie: the return value of dma_alloc_attrs(), keep it for dma_free_attrs()
- * @kvaddr: kernel virtual address of gem buffer.
- * @dma_addr: dma address of gem buffer.
- * @dma_attrs: dma attributes of gem buffer.
- *
- * P.S. this object would be transferred to user as kms_bo.handle so
- *	user can access the buffer through kms_bo.handle.
- */
-struct mtk_gem_obj {
-	struct drm_gem_object	base;
-	void			*cookie;
-	void			*kvaddr;
-	dma_addr_t		dma_addr;
-	unsigned long		dma_attrs;
-	struct sg_table		*sg;
-	struct page		**pages;
-};
-
-#define to_mtk_gem_obj(x) container_of(x, struct mtk_gem_obj, base)
-
-void mtk_gem_free_object(struct drm_gem_object *gem);
-struct mtk_gem_obj *mtk_gem_create(struct drm_device *dev, size_t size,
-				   bool alloc_kmap);
 int mtk_gem_dumb_create(struct drm_file *file_priv, struct drm_device *dev,
 			struct drm_mode_create_dumb *args);
-struct sg_table *mtk_gem_prime_get_sg_table(struct drm_gem_object *obj);
 struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev,
 			struct dma_buf_attachment *attach, struct sg_table *sg);
-int mtk_gem_prime_vmap(struct drm_gem_object *obj, struct iosys_map *map);
-void mtk_gem_prime_vunmap(struct drm_gem_object *obj, struct iosys_map *map);
 
 #endif
diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi_common.c b/drivers/gpu/drm/mediatek/mtk_hdmi_common.c
index e78eb0876f16..bd7f8c56ec9c 100644
--- a/drivers/gpu/drm/mediatek/mtk_hdmi_common.c
+++ b/drivers/gpu/drm/mediatek/mtk_hdmi_common.c
@@ -303,7 +303,7 @@ static int mtk_hdmi_dt_parse_pdata(struct mtk_hdmi *hdmi, struct platform_device
 		return dev_err_probe(dev, ret, "Failed to get clocks\n");
 
 	hdmi->irq = platform_get_irq(pdev, 0);
-	if (!hdmi->irq)
+	if (hdmi->irq < 0)
 		return hdmi->irq;
 
 	hdmi->regs = device_node_to_regmap(dev->of_node);
diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi_common.h b/drivers/gpu/drm/mediatek/mtk_hdmi_common.h
index de5e064585f8..7a644bbf5843 100644
--- a/drivers/gpu/drm/mediatek/mtk_hdmi_common.h
+++ b/drivers/gpu/drm/mediatek/mtk_hdmi_common.h
@@ -168,7 +168,7 @@ struct mtk_hdmi {
 	bool audio_enable;
 	bool powered;
 	bool enabled;
-	unsigned int irq;
+	int irq;
 	enum hdmi_hpd_state hpd;
 	hdmi_codec_plugged_cb plugged_cb;
 	struct device *codec_dev;
diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi_ddc_v2.c b/drivers/gpu/drm/mediatek/mtk_hdmi_ddc_v2.c
index b844e2c10f28..d937219fdb7e 100644
--- a/drivers/gpu/drm/mediatek/mtk_hdmi_ddc_v2.c
+++ b/drivers/gpu/drm/mediatek/mtk_hdmi_ddc_v2.c
@@ -66,11 +66,19 @@ static int mtk_ddc_check_and_rise_low_bus(struct mtk_hdmi_ddc *ddc)
 	return 0;
 }
 
-static int mtk_ddc_wr_one(struct mtk_hdmi_ddc *ddc, u16 addr_id,
-			  u16 offset_id, u8 *wr_data)
+static int mtk_ddcm_write_hdmi(struct mtk_hdmi_ddc *ddc, u16 addr_id,
+			       u16 offset_id, u16 data_cnt, u8 *wr_data)
 {
 	u32 val;
-	int ret;
+	int ret, i;
+
+	/* Don't allow transfer with a size over than the transfer fifo size
+	 * (16 byte)
+	 */
+	if (data_cnt > 16) {
+		dev_err(ddc->dev, "Invalid DDCM write request\n");
+		return -EINVAL;
+	}
 
 	/* If down, rise bus for write operation */
 	mtk_ddc_check_and_rise_low_bus(ddc);
@@ -78,16 +86,21 @@ static int mtk_ddc_wr_one(struct mtk_hdmi_ddc *ddc, u16 addr_id,
 	regmap_update_bits(ddc->regs, HPD_DDC_CTRL, HPD_DDC_DELAY_CNT,
 			   FIELD_PREP(HPD_DDC_DELAY_CNT, DDC2_DLY_CNT));
 
+	/* In case there is no payload data, just do a single write for the
+	 * address only
+	 */
 	if (wr_data) {
-		regmap_write(ddc->regs, SI2C_CTRL,
-			     FIELD_PREP(SI2C_ADDR, SI2C_ADDR_READ) |
-			     FIELD_PREP(SI2C_WDATA, *wr_data) |
-			     SI2C_WR);
+		/* Fill transfer fifo with payload data */
+		for (i = 0; i < data_cnt; i++) {
+			regmap_write(ddc->regs, SI2C_CTRL,
+				     FIELD_PREP(SI2C_ADDR, SI2C_ADDR_READ) |
+				     FIELD_PREP(SI2C_WDATA, wr_data[i]) |
+				     SI2C_WR);
+		}
 	}
-
 	regmap_write(ddc->regs, DDC_CTRL,
 		     FIELD_PREP(DDC_CTRL_CMD, DDC_CMD_SEQ_WRITE) |
-		     FIELD_PREP(DDC_CTRL_DIN_CNT, wr_data == NULL ? 0 : 1) |
+		     FIELD_PREP(DDC_CTRL_DIN_CNT, wr_data == NULL ? 0 : data_cnt) |
 		     FIELD_PREP(DDC_CTRL_OFFSET, offset_id) |
 		     FIELD_PREP(DDC_CTRL_ADDR, addr_id));
 	usleep_range(1000, 1250);
@@ -96,6 +109,11 @@ static int mtk_ddc_wr_one(struct mtk_hdmi_ddc *ddc, u16 addr_id,
 				       !(val & DDC_I2C_IN_PROG), 500, 1000);
 	if (ret) {
 		dev_err(ddc->dev, "DDC I2C write timeout\n");
+
+		/* Abort transfer if it is still in progress */
+		regmap_update_bits(ddc->regs, DDC_CTRL, DDC_CTRL_CMD,
+				   FIELD_PREP(DDC_CTRL_CMD, DDC_CMD_ABORT_XFER));
+
 		return ret;
 	}
 
@@ -179,6 +197,11 @@ static int mtk_ddcm_read_hdmi(struct mtk_hdmi_ddc *ddc, u16 uc_dev,
 					       500 * (temp_length + 5));
 		if (ret) {
 			dev_err(ddc->dev, "Timeout waiting for DDC I2C\n");
+
+			/* Abort transfer if it is still in progress */
+			regmap_update_bits(ddc->regs, DDC_CTRL, DDC_CTRL_CMD,
+					   FIELD_PREP(DDC_CTRL_CMD, DDC_CMD_ABORT_XFER));
+
 			return ret;
 		}
 
@@ -250,24 +273,9 @@ static int mtk_hdmi_fg_ddc_data_read(struct mtk_hdmi_ddc *ddc, u16 b_dev,
 static int mtk_hdmi_ddc_fg_data_write(struct mtk_hdmi_ddc *ddc, u16 b_dev,
 				      u8 data_addr, u16 data_cnt, u8 *pr_data)
 {
-	int i, ret;
-
 	regmap_set_bits(ddc->regs, HDCP2X_POL_CTRL, HDCP2X_DIS_POLL_EN);
-	/*
-	 * In case there is no payload data, just do a single write for the
-	 * address only
-	 */
-	if (data_cnt == 0)
-		return mtk_ddc_wr_one(ddc, b_dev, data_addr, NULL);
 
-	i = 0;
-	do {
-		ret = mtk_ddc_wr_one(ddc, b_dev, data_addr + i, pr_data + i);
-		if (ret)
-			return ret;
-	} while (++i < data_cnt);
-
-	return 0;
+	return mtk_ddcm_write_hdmi(ddc, b_dev, data_addr, data_cnt, pr_data);
 }
 
 static int mtk_hdmi_ddc_v2_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num)
diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi_v2.c b/drivers/gpu/drm/mediatek/mtk_hdmi_v2.c
index c272e1e74b7d..454b8b93b834 100644
--- a/drivers/gpu/drm/mediatek/mtk_hdmi_v2.c
+++ b/drivers/gpu/drm/mediatek/mtk_hdmi_v2.c
@@ -1120,9 +1120,10 @@ static void mtk_hdmi_v2_hpd_disable(struct drm_bridge *bridge)
 	mtk_hdmi_v2_disable(hdmi);
 }
 
-static int mtk_hdmi_v2_hdmi_tmds_char_rate_valid(const struct drm_bridge *bridge,
-						 const struct drm_display_mode *mode,
-						 unsigned long long tmds_rate)
+static enum drm_mode_status
+mtk_hdmi_v2_hdmi_tmds_char_rate_valid(const struct drm_bridge *bridge,
+				      const struct drm_display_mode *mode,
+				      unsigned long long tmds_rate)
 {
 	if (mode->clock < MTK_HDMI_V2_CLOCK_MIN)
 		return MODE_CLOCK_LOW;
diff --git a/drivers/gpu/drm/mediatek/mtk_plane.c b/drivers/gpu/drm/mediatek/mtk_plane.c
index 5043e0377270..fcd10d7e8342 100644
--- a/drivers/gpu/drm/mediatek/mtk_plane.c
+++ b/drivers/gpu/drm/mediatek/mtk_plane.c
@@ -11,13 +11,13 @@
 #include <drm/drm_fourcc.h>
 #include <drm/drm_framebuffer.h>
 #include <drm/drm_gem_atomic_helper.h>
+#include <drm/drm_gem_dma_helper.h>
 #include <drm/drm_print.h>
 #include <linux/align.h>
 
 #include "mtk_crtc.h"
 #include "mtk_ddp_comp.h"
 #include "mtk_drm_drv.h"
-#include "mtk_gem.h"
 #include "mtk_plane.h"
 
 static const u64 modifiers[] = {
@@ -114,8 +114,8 @@ static void mtk_plane_update_new_state(struct drm_plane_state *new_state,
 				       struct mtk_plane_state *mtk_plane_state)
 {
 	struct drm_framebuffer *fb = new_state->fb;
+	struct drm_gem_dma_object *dma_obj;
 	struct drm_gem_object *gem;
-	struct mtk_gem_obj *mtk_gem;
 	unsigned int pitch, format;
 	u64 modifier;
 	dma_addr_t addr;
@@ -124,8 +124,8 @@ static void mtk_plane_update_new_state(struct drm_plane_state *new_state,
 	int offset;
 
 	gem = fb->obj[0];
-	mtk_gem = to_mtk_gem_obj(gem);
-	addr = mtk_gem->dma_addr;
+	dma_obj = to_drm_gem_dma_obj(gem);
+	addr = dma_obj->dma_addr;
 	pitch = fb->pitches[0];
 	format = fb->format->format;
 	modifier = fb->modifier;