vo_drm: add support for YUYV format

As the first aligned format this required a fix to reconfig().

Adding the other component-swapped formats in this group would be trivial
but I checked the DRM database [1] and no driver exists that supports
one of those but not YUYV and this is quite fringe as-is, so I opted not to.

[1] <https://drmdb.emersion.fr/formats>

DOCS/man/vo.rst

@@ -627,17 +627,20 @@ Available video output drivers are:
         lower resolution (the video when handled by the hwdec will be on the
         drmprime-video plane and at full 4K resolution)
 
-    ``--drm-format=<xrgb8888|xrgb2101010>``
+    ``--drm-format=<xrgb8888|xbgr8888|xrgb2101010|xbgr2101010|yuyv>``
         Select the DRM format to use (default: xrgb8888). This allows you to
-        choose the bit depth of the DRM mode. xrgb8888 is your usual 24 bit per
-        pixel/8 bits per channel packed RGB format with 8 bits of padding.
-        xrgb2101010 is a packed 30 bits per pixel/10 bits per channel packed RGB
-        format with 2 bits of padding.
+        choose the bit depth and color type of the DRM mode.
+
+        xrgb8888 is your usual 24bpp packed RGB format with 8 bits of padding.
+        xrgb2101010 is a 30bpp packed RGB format with 2 bits of padding.
+        yuyv is a 32bpp packed YUV 4:2:2 format. No planar formats are currently
+        supported.
 
         There are cases when xrgb2101010 will work with the ``drm`` VO, but not
         with the ``drm`` backend for the ``gpu`` VO. This is because with the
         ``gpu`` VO, in addition to requiring support in your DRM driver,
-        requires support for xrgb2101010 in your EGL driver
+        requires support for xrgb2101010 in your EGL driver.
+        yuyv only ever works with the ``drm`` VO.
 
     ``--drm-draw-surface-size=<[WxH]>``
         Sets the size of the surface used on the draw plane. The surface will

video/out/drm_common.c

@@ -95,7 +95,8 @@ const struct m_sub_options drm_conf = {
             {"xrgb8888",    DRM_OPTS_FORMAT_XRGB8888},
             {"xrgb2101010", DRM_OPTS_FORMAT_XRGB2101010},
             {"xbgr8888",    DRM_OPTS_FORMAT_XBGR8888},
-            {"xbgr2101010", DRM_OPTS_FORMAT_XBGR2101010})},
+            {"xbgr2101010", DRM_OPTS_FORMAT_XBGR2101010},
+            {"yuyv",        DRM_OPTS_FORMAT_YUYV})},
         {"drm-draw-surface-size", OPT_SIZE_BOX(draw_surface_size)},
         {"drm-vrr-enabled", OPT_CHOICE(vrr_enabled,
             {"no", 0}, {"yes", 1}, {"auto", -1})},
@@ -106,6 +107,7 @@ const struct m_sub_options drm_conf = {
         .drm_atomic = 1,
         .draw_plane = DRM_OPTS_PRIMARY_PLANE,
         .drmprime_video_plane = DRM_OPTS_OVERLAY_PLANE,
+        .drm_format = DRM_OPTS_FORMAT_XRGB8888,
     },
     .size = sizeof(struct drm_opts),
 };

video/out/drm_common.h

@@ -23,10 +23,13 @@
 #include <xf86drmMode.h>
 #include "vo.h"
 
-#define DRM_OPTS_FORMAT_XRGB8888    0
-#define DRM_OPTS_FORMAT_XRGB2101010 1
-#define DRM_OPTS_FORMAT_XBGR8888    2
-#define DRM_OPTS_FORMAT_XBGR2101010 3
+enum {
+    DRM_OPTS_FORMAT_XRGB8888,
+    DRM_OPTS_FORMAT_XRGB2101010,
+    DRM_OPTS_FORMAT_XBGR8888,
+    DRM_OPTS_FORMAT_XBGR2101010,
+    DRM_OPTS_FORMAT_YUYV,
+};
 
 struct framebuffer {
     int fd;

video/out/vo_drm.c

@@ -43,6 +43,7 @@
     pixfmt2imgfmt(MP_SELECT_LE_BE(AV_PIX_FMT_X2RGB10LE, AV_PIX_FMT_X2RGB10BE))
 #define IMGFMT_XBGR2101010 \
     pixfmt2imgfmt(MP_SELECT_LE_BE(AV_PIX_FMT_X2BGR10LE, AV_PIX_FMT_X2BGR10BE))
+#define IMGFMT_YUYV pixfmt2imgfmt(AV_PIX_FMT_YUYV422)
 
 #define BYTES_PER_PIXEL 4
 #define BITS_PER_PIXEL 32
@@ -131,6 +132,10 @@ static struct framebuffer *setup_framebuffer(struct vo *vo)
         p->drm_format = DRM_FORMAT_XBGR8888;
         p->imgfmt = IMGFMT_XBGR8888;
         break;
+    case DRM_OPTS_FORMAT_YUYV:
+        p->drm_format = DRM_FORMAT_YUYV;
+        p->imgfmt = IMGFMT_YUYV;
+        break;
     default:
         if (drm->opts->drm_format != DRM_OPTS_FORMAT_XRGB8888) {
             MP_VERBOSE(vo, "Requested format not supported by VO, "
@@ -187,14 +192,15 @@ static int reconfig(struct vo *vo, struct mp_image_params *params)
     vo->dheight = drm->fb->height;
     vo_get_src_dst_rects(vo, &p->src, &p->dst, &p->osd);
 
-    int w = p->dst.x1 - p->dst.x0;
-    int h = p->dst.y1 - p->dst.y0;
+    struct mp_imgfmt_desc fmt = mp_imgfmt_get_desc(p->imgfmt);
+    p->dst.x0 = MP_ALIGN_DOWN(p->dst.x0, fmt.align_x);
+    p->dst.y0 = MP_ALIGN_DOWN(p->dst.y0, fmt.align_y);
 
     p->sws->src = *params;
     p->sws->dst = (struct mp_image_params) {
         .imgfmt = p->imgfmt,
-        .w = w,
-        .h = h,
+        .w = mp_rect_w(p->dst),
+        .h = mp_rect_h(p->dst),
         .p_w = 1,
         .p_h = 1,
     };