On 25/2/25 01:10, Hans Verkuil wrote:
Commit c780d01cf1a6 ("media: vb2: vb2_core_queue_init(): sanity check lock and
wait_prepare/finish") added a sanity check to ensure that if there are no
wait_prepare/finish callbacks set by the driver, then the vb2_queue lock must
be set, since otherwise the vb2 core cannot do correct locking.
The rtl2832_sdr.c triggered this warning: it turns out that while the driver
does set this lock, it sets it too late. So move it up to before the
vb2_queue_init() call.
Reported-by: Arthur Marsh<arthur.marsh@xxxxxxxxxxxxxxxx>
Fixes: 8fcd2795d22a ("media: rtl2832_sdr: drop vb2_ops_wait_prepare/finish")
Cc:stable@xxxxxxxxxxxxxxx
Signed-off-by: Hans Verkuil<hverkuil@xxxxxxxxx>
---
Arthur, it would be great if you can test this patch!
Regards,
Hans
---
diff --git a/drivers/media/dvb-frontends/rtl2832_sdr.c b/drivers/media/dvb-frontends/rtl2832_sdr.c
index 05254d8717db..0357624968f1 100644
--- a/drivers/media/dvb-frontends/rtl2832_sdr.c
+++ b/drivers/media/dvb-frontends/rtl2832_sdr.c
@@ -1363,6 +1363,7 @@ static int rtl2832_sdr_probe(struct platform_device *pdev)
dev->vb_queue.ops = &rtl2832_sdr_vb2_ops;
dev->vb_queue.mem_ops = &vb2_vmalloc_memops;
dev->vb_queue.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
+ dev->vb_queue.lock = &dev->vb_queue_lock;
ret = vb2_queue_init(&dev->vb_queue);
if (ret) {
dev_err(&pdev->dev, "Could not initialize vb2 queue\n");
@@ -1421,7 +1422,6 @@ static int rtl2832_sdr_probe(struct platform_device *pdev)
/* Init video_device structure */
dev->vdev = rtl2832_sdr_template;
dev->vdev.queue = &dev->vb_queue;
- dev->vdev.queue->lock = &dev->vb_queue_lock;
video_set_drvdata(&dev->vdev, dev);
/* Register the v4l2_device structure */
Hi and thanks, I applied the above patch to kernel 6.14.0-rc4, built and
rebooted into the patched kernel, and ran:
dmesg|egrep '(rtl|2832)'
[ 396.972457] usb 2-3: dvb_usb_v2: found a 'Realtek RTL2832U reference
design'
in warm state
[ 397.004068] dvbdev: DVB: registering new adapter (Realtek RTL2832U
reference
design)
[ 397.194478] rtl2832 5-0010: Realtek RTL2832 successfully attached
[ 397.194497] usb 2-3: DVB: registering adapter 0 frontend 0 (Realtek
RTL2832 (
DVB-T))...
[ 397.194505] dvbdev: dvb_create_media_entity: media entity 'Realtek
RTL2832 (D
VB-T)' registered.
[ 397.822338] rtl2832_sdr rtl2832_sdr.1.auto: Registered as swradio0
[ 397.822342] rtl2832_sdr rtl2832_sdr.1.auto: Realtek RTL2832 SDR attached
[ 397.822343] rtl2832_sdr rtl2832_sdr.1.auto: SDR API is still slightly
experim
ental and functionality changes may follow
[ 397.838919] usb 2-3: dvb_usb_v2: 'Realtek RTL2832U reference design'
successf
ully initialized and connected
[ 397.840353] usbcore: registered new interface driver dvb_usb_rtl28xxu
I haven't used the Software Defined Radio functionality, but was able to
successfully view and listen to a DVB-T stream from the RTL2832.
Regards,
Arthur.
