request: route VP9/AV1/H.264 to daedalus_v4l2 on Pi 5 mixed deploy

LIBVA-1 — when both rpi-hevc-dec and daedalus_v4l2 are loaded, finish
the per-codec dispatch so HEVC goes to rpi-hevc-dec (existing 'p'
override) and VP9 / AV1 / H.264 go to the daedalus daemon ('d').

Before this change the multi-device-probe accepted only ONE driver
plus a fixed alt slot (rkvdec↔hantro-vpu); on a Pi 5 with both decoders
the find_codec_device() walk preferred rpi-hevc-dec by known_decoder_
drivers[] order and never opened daedalus_v4l2, so VP9/AV1/H.264 frames
hit rpi-hevc-dec's S_FMT and failed.

Changes:

  - request.c multi-device-probe: when primary = rpi-hevc-dec, alt =
    daedalus_v4l2 (when HAVE_DAEDALUS_V4L2 is on); symmetric handling
    in the daedalus_v4l2 primary branch so alt = rpi-hevc-dec.  This
    preserves the iter40 fallback (no daedalus → alt = NULL) when the
    build option is off.

  - request.c alt-driver opening block: generalized from the iter38
    rkvdec/hantro pair to also dispatch into video_fd_rpi_hevc_dec and
    video_fd_daedalus slots.  Defensive close on unknown alt-driver
    name (shouldn't happen — primary_driver branches gate the choices —
    but keeps the slot tally clean if a future driver name is added
    above without wiring up the dispatch here).

  - request_switch_device_for_profile: added 'd' kind handler +
    profile override block.  When daedalus is open, VP9 / AV1 / H.264*
    route to it.  HEVC stays on rpi-hevc-dec via the existing 'p'
    override.  AV1 'a' kind (RK3588 vpu981) wins ONLY if vpu981 was
    probed, so the override only fires on hosts where vpu981 stayed
    -1 (i.e. Pi 5).

  - RequestTerminate: close the daedalus_v4l2 fd pair on teardown
    (was leaking — caught while reviewing the alt-driver expansion).

Build: meson + ninja clean on boltzmann (only pre-existing GStreamer
H265 parser noise).  Behaviour on RK3399/3588 boxes unchanged — the
new branches are gated by HAVE_DAEDALUS_V4L2 *and* video_fd_daedalus
≥ 0, both of which stay false in those deployments.

Companion to daedalus-v4l2 481279c (Phase 8.13 systemd unit) and
marfrit-packages noether/daedalus-v4l2-kernel-6.18-compat branch.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/request.c

@@ -461,6 +461,44 @@ int request_switch_device_for_profile(struct request_data *driver_data,
 		kind = 'p';
 	}
 
+#ifdef HAVE_DAEDALUS_V4L2
+	/*
+	 * LIBVA-1: VP9/AV1/H.264 → daedalus_v4l2 when the daemon-backed
+	 * decoder fd is open.  Pi 5 has no rkvdec (those profiles map to
+	 * 'r' by default → video_fd_rkvdec = -1 → "stay on whatever's
+	 * active" fallback would put H.264 frames on rpi-hevc-dec's fd
+	 * and S_FMT would fail).  Re-route to the daedalus daemon instead.
+	 *
+	 * HEVC stays on 'p' (rpi-hevc-dec is HEVC-only — daedalus would
+	 * accept it via FFmpeg, but rpi-hevc-dec has the GPU-backed
+	 * hardware path so it's the right choice on this SoC).
+	 *
+	 * AV1 'a' kind (RK3588 vpu981) wins ONLY if vpu981 was probed.
+	 * On a Pi 5 the vpu981 slot stays -1, so we still route AV1 to
+	 * daedalus here.  Check video_fd_vpu981 to preserve the RK3588
+	 * priority for that case.
+	 */
+	if (driver_data->video_fd_daedalus >= 0 &&
+	    driver_data->media_fd_daedalus >= 0) {
+		switch (profile) {
+		case VAProfileH264Main:
+		case VAProfileH264High:
+		case VAProfileH264ConstrainedBaseline:
+		case VAProfileH264MultiviewHigh:
+		case VAProfileH264StereoHigh:
+		case VAProfileVP9Profile0:
+			kind = 'd';
+			break;
+		case VAProfileAV1Profile0:
+			if (driver_data->video_fd_vpu981 < 0)
+				kind = 'd';
+			break;
+		default:
+			break;
+		}
+	}
+#endif
+
 	if (kind == 'r') {
 		target_video = driver_data->video_fd_rkvdec;
 		target_media = driver_data->media_fd_rkvdec;
@@ -473,6 +511,11 @@ int request_switch_device_for_profile(struct request_data *driver_data,
 	} else if (kind == 'a') {
 		target_video = driver_data->video_fd_vpu981;
 		target_media = driver_data->media_fd_vpu981;
+#ifdef HAVE_DAEDALUS_V4L2
+	} else if (kind == 'd') {
+		target_video = driver_data->video_fd_daedalus;
+		target_media = driver_data->media_fd_daedalus;
+#endif
 	} else {
 		return -1;
 	}
@@ -697,26 +740,32 @@ VAStatus VA_DRIVER_INIT_FUNC(VADriverContextP context)
 				driver_data->video_fd_hantro = video_fd;
 				driver_data->media_fd_hantro = media_fd;
 			} else if (strcmp(info.driver, "rpi-hevc-dec") == 0) {
-				/* iter40: Pi 5 / CM5 — sole decoder is rpi-hevc-dec.
+				/* iter40 + LIBVA-1: Pi 5 / CM5.  rpi-hevc-dec is
-				 * No alt driver to probe; the rkvdec / hantro slots
+				 * HEVC-only.  If daedalus_v4l2 is ALSO loaded (Pi 5
-				 * stay -1 and HEVC routes to 'p' via
+				 * mixed deployment — out-of-tree daemon-backed
-				 * request_device_kind_for_profile. */
+				 * decoder for VP9/AV1/H264), pick it up as the alt
+				 * so VP9/AV1/H264 have somewhere to land. */
 				primary_driver = "rpi-hevc-dec";
+#ifdef HAVE_DAEDALUS_V4L2
+				alt_driver = "daedalus_v4l2";
+#else
 				alt_driver = NULL;
+#endif
 				driver_data->video_fd_rpi_hevc_dec = video_fd;
 				driver_data->media_fd_rpi_hevc_dec = media_fd;
 #ifdef HAVE_DAEDALUS_V4L2
 			} else if (strcmp(info.driver, "daedalus_v4l2") == 0) {
-				/* phase 8.10: Pi 5 daemon-backed decoder.  Sole
+				/* phase 8.10 + LIBVA-1: Pi 5 daemon-backed decoder.
-				 * V4L2 stateless slot on this kernel; VP9 / AV1 /
+				 * VP9 / AV1 / H.264 route through it via the 'd'
-				 * H.264 all route through it.  Other slots stay -1.
+				 * kind below.  On a mixed-driver box where
-				 *
+				 * rpi-hevc-dec is ALSO loaded, pick it up as the
-				 * On a mixed-driver box (daedalus loaded ALONGSIDE
+				 * alt so HEVC has somewhere to land too — find_
-				 * rpi-hevc-dec) HEVC would prefer rpi-hevc-dec via
+				 * codec_device's known_decoder_drivers[] order
-				 * the existing 'p' override; VP9/AV1/H264 prefer
+				 * normally puts rpi-hevc-dec first (we hit the
-				 * daedalus_v4l2 since rpi-hevc-dec is HEVC-only. */
+				 * other branch in practice), but symmetric handling
+				 * keeps us correct if probe order ever flips. */
 				primary_driver = "daedalus_v4l2";
-				alt_driver = NULL;
+				alt_driver = "rpi-hevc-dec";
 				driver_data->video_fd_daedalus = video_fd;
 				driver_data->media_fd_daedalus = media_fd;
 #endif
@@ -731,15 +780,38 @@ VAStatus VA_DRIVER_INIT_FUNC(VADriverContextP context)
 				int alt_v = open(alt_video, O_RDWR | O_NONBLOCK);
 				int alt_m = (alt_v >= 0) ? open(alt_media, O_RDWR | O_NONBLOCK) : -1;
 				if (alt_v >= 0 && alt_m >= 0) {
+					/* Dispatch into the matching per-driver slot.
+					 * iter38 only had rkvdec/hantro pairs; iter40 +
+					 * LIBVA-1 extended this to rpi-hevc-dec and
+					 * daedalus_v4l2 for the Pi 5 mixed-decoder
+					 * deployment. */
 					if (strcmp(alt_driver, "rkvdec") == 0) {
 						driver_data->video_fd_rkvdec = alt_v;
 						driver_data->media_fd_rkvdec = alt_m;
-					} else {
+					} else if (strcmp(alt_driver, "hantro-vpu") == 0) {
 						driver_data->video_fd_hantro = alt_v;
 						driver_data->media_fd_hantro = alt_m;
+					} else if (strcmp(alt_driver, "rpi-hevc-dec") == 0) {
+						driver_data->video_fd_rpi_hevc_dec = alt_v;
+						driver_data->media_fd_rpi_hevc_dec = alt_m;
+#ifdef HAVE_DAEDALUS_V4L2
+					} else if (strcmp(alt_driver, "daedalus_v4l2") == 0) {
+						driver_data->video_fd_daedalus = alt_v;
+						driver_data->media_fd_daedalus = alt_m;
+#endif
+					} else {
+						/* Shouldn't happen — primary_driver branches
+						 * above only set alt_driver to one of the
+						 * names handled here.  Close and move on. */
+						close(alt_v);
+						close(alt_m);
+						alt_v = -1;
+						alt_m = -1;
+					}
+					if (alt_v >= 0) {
+						request_log("iter38: also opened %s decoder at %s + %s\n",
+							    alt_driver, alt_video, alt_media);
 					}
-					request_log("iter38: also opened %s decoder at %s + %s\n",
-						    alt_driver, alt_video, alt_media);
 				} else {
 					if (alt_v >= 0) close(alt_v);
 					if (alt_m >= 0) close(alt_m);
@@ -890,6 +962,12 @@ VAStatus RequestTerminate(VADriverContextP context)
 		close(driver_data->video_fd_vpu981);
 	if (driver_data->media_fd_vpu981 >= 0)
 		close(driver_data->media_fd_vpu981);
+#ifdef HAVE_DAEDALUS_V4L2
+	if (driver_data->video_fd_daedalus >= 0)
+		close(driver_data->video_fd_daedalus);
+	if (driver_data->media_fd_daedalus >= 0)
+		close(driver_data->media_fd_daedalus);
+#endif
 	/* Fall back to direct close if neither alt fd captured the active
 	 * pair (env-override path). */
 	if (driver_data->video_fd_rkvdec < 0 && driver_data->video_fd_hantro < 0) {