[PATCH 1/2] media: v4l2-common: add v4l2_fill_pixfmt_aligned() helper

[Tommaso Merciai]

Add v4l2_fill_pixfmt_aligned(), a variant of v4l2_fill_pixfmt()
that accepts a stride_alignment parameter, mirroring the existing
v4l2_fill_pixfmt_mp() / v4l2_fill_pixfmt_mp_aligned() pair.

v4l2_fill_pixfmt() is refactored to call v4l2_fill_pixfmt_aligned()
with stride_alignment=1, preserving its existing behaviour.

The new helper is needed by drivers whose DMA engine requires the
line stride to be a multiple of a specific value, such as the
Renesas RZ/G3E CRU which requires 128-byte alignment.

Signed-off-by: Tommaso Merciai <tommaso.merciai.xr@xxxxxxxxxxxxxx>
---
 drivers/media/v4l2-core/v4l2-common.c | 17 +++++++++++++----
 include/media/v4l2-common.h           |  3 +++
 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c
index 65db7340ad38..1de246acc7ab 100644
--- a/drivers/media/v4l2-core/v4l2-common.c
+++ b/drivers/media/v4l2-core/v4l2-common.c
@@ -545,8 +545,8 @@ int v4l2_fill_pixfmt_mp(struct v4l2_pix_format_mplane *pixfmt,
 }
 EXPORT_SYMBOL_GPL(v4l2_fill_pixfmt_mp);
 
-int v4l2_fill_pixfmt(struct v4l2_pix_format *pixfmt, u32 pixelformat,
-		     u32 width, u32 height)
+int v4l2_fill_pixfmt_aligned(struct v4l2_pix_format *pixfmt, u32 pixelformat,
+			     u32 width, u32 height, u8 stride_alignment)
 {
 	const struct v4l2_format_info *info;
 	int i;
@@ -562,14 +562,23 @@ int v4l2_fill_pixfmt(struct v4l2_pix_format *pixfmt, u32 pixelformat,
 	pixfmt->width = width;
 	pixfmt->height = height;
 	pixfmt->pixelformat = pixelformat;
-	pixfmt->bytesperline = v4l2_format_plane_stride(info, 0, width, 1);
+	pixfmt->bytesperline = v4l2_format_plane_stride(info, 0, width,
+							stride_alignment);
 	pixfmt->sizeimage = 0;
 
 	for (i = 0; i < info->comp_planes; i++)
 		pixfmt->sizeimage +=
-			v4l2_format_plane_size(info, i, width, height, 1);
+			v4l2_format_plane_size(info, i, width, height,
+					       stride_alignment);
 	return 0;
 }
+EXPORT_SYMBOL_GPL(v4l2_fill_pixfmt_aligned);
+
+int v4l2_fill_pixfmt(struct v4l2_pix_format *pixfmt, u32 pixelformat,
+		     u32 width, u32 height)
+{
+	return v4l2_fill_pixfmt_aligned(pixfmt, pixelformat, width, height, 1);
+}
 EXPORT_SYMBOL_GPL(v4l2_fill_pixfmt);
 
 #ifdef CONFIG_MEDIA_CONTROLLER
diff --git a/include/media/v4l2-common.h b/include/media/v4l2-common.h
index edd416178c33..718a0f47f36b 100644
--- a/include/media/v4l2-common.h
+++ b/include/media/v4l2-common.h
@@ -556,6 +556,9 @@ void v4l2_apply_frmsize_constraints(u32 *width, u32 *height,
 				    const struct v4l2_frmsize_stepwise *frmsize);
 int v4l2_fill_pixfmt(struct v4l2_pix_format *pixfmt, u32 pixelformat,
 		     u32 width, u32 height);
+/* @stride_alignment is a power of 2 value in bytes */
+int v4l2_fill_pixfmt_aligned(struct v4l2_pix_format *pixfmt, u32 pixelformat,
+			     u32 width, u32 height, u8 stride_alignment);
 int v4l2_fill_pixfmt_mp(struct v4l2_pix_format_mplane *pixfmt, u32 pixelformat,
 			u32 width, u32 height);
 /* @stride_alignment is a power of 2 value in bytes */
-- 
2.54.0