media: nxp: imx8-isi: Fix streaming cleanup on release

The current implementation unconditionally calls
mxc_isi_video_cleanup_streaming() in mxc_isi_video_release(). This can
lead to situations where any release call (like from a simple
"v4l2-ctl -l") may release a currently streaming queue when called on
such a device.

This is reproducible on an i.MX8MP board by streaming from an ISI
capture device using gstreamer:

	gst-launch-1.0 -v v4l2src device=/dev/videoX ! \
	    video/x-raw,format=GRAY8,width=1280,height=800,framerate=1/120 ! \
	    fakesink

While this stream is running, querying the caps of the same device
provokes the error state:

	v4l2-ctl -l -d /dev/videoX

This results in the following trace:

[  155.452152] ------------[ cut here ]------------
[  155.452163] WARNING: CPU: 0 PID: 1708 at drivers/media/platform/nxp/imx8-isi/imx8-isi-pipe.c:713 mxc_isi_pipe_irq_handler+0x19c/0x1b0 [imx8_isi]
[  157.004248] Modules linked in: cfg80211 rpmsg_ctrl rpmsg_char rpmsg_tty virtio_rpmsg_bus rpmsg_ns rpmsg_core rfkill nft_ct nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables mcp251x6
[  157.053499] CPU: 0 UID: 0 PID: 1708 Comm: python3 Not tainted 6.15.4-00114-g1f61ca5cad76 #1 PREEMPT
[  157.064369] Hardware name: imx8mp_board_01 (DT)
[  157.068205] pstate: 400000c5 (nZcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[  157.075169] pc : mxc_isi_pipe_irq_handler+0x19c/0x1b0 [imx8_isi]
[  157.081195] lr : mxc_isi_pipe_irq_handler+0x38/0x1b0 [imx8_isi]
[  157.087126] sp : ffff800080003ee0
[  157.090438] x29: ffff800080003ee0 x28: ffff0000c3688000 x27: 0000000000000000
[  157.097580] x26: 0000000000000000 x25: ffff0000c1e7ac00 x24: ffff800081b5ad50
[  157.104723] x23: 00000000000000d1 x22: 0000000000000000 x21: ffff0000c25e4000
[  157.111866] x20: 0000000060000200 x19: ffff80007a0608d0 x18: 0000000000000000
[  157.119008] x17: ffff80006a4e3000 x16: ffff800080000000 x15: 0000000000000000
[  157.126146] x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
[  157.133287] x11: 0000000000000040 x10: ffff0000c01445f0 x9 : ffff80007a053a38
[  157.140425] x8 : ffff0000c04004b8 x7 : 0000000000000000 x6 : 0000000000000000
[  157.147567] x5 : ffff0000c0400490 x4 : ffff80006a4e3000 x3 : ffff0000c25e4000
[  157.154706] x2 : 0000000000000000 x1 : ffff8000825c0014 x0 : 0000000060000200
[  157.161850] Call trace:
[  157.164296]  mxc_isi_pipe_irq_handler+0x19c/0x1b0 [imx8_isi] (P)
[  157.170319]  __handle_irq_event_percpu+0x58/0x218
[  157.175029]  handle_irq_event+0x54/0xb8
[  157.178867]  handle_fasteoi_irq+0xac/0x248
[  157.182968]  handle_irq_desc+0x48/0x68
[  157.186723]  generic_handle_domain_irq+0x24/0x38
[  157.191346]  gic_handle_irq+0x54/0x120
[  157.195098]  call_on_irq_stack+0x24/0x30
[  157.199027]  do_interrupt_handler+0x88/0x98
[  157.203212]  el0_interrupt+0x44/0xc0
[  157.206792]  __el0_irq_handler_common+0x18/0x28
[  157.211328]  el0t_64_irq_handler+0x10/0x20
[  157.215429]  el0t_64_irq+0x198/0x1a0
[  157.219009] ---[ end trace 0000000000000000 ]---

Address this issue by moving the streaming preparation and cleanup to
the vb2 .prepare_streaming() and .unprepare_streaming() operations. This
also simplifies the driver by allowing direct usage of the
vb2_ioctl_streamon() and vb2_ioctl_streamoff() helpers, and removal of
the manual cleanup from mxc_isi_video_release().

Link: https://lore.kernel.org/r/20250813212451.22140-2-laurent.pinchart@ideasonboard.com
Signed-off-by: Richard Leitner <richard.leitner@linux.dev>
Co-developed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Richard Leitner <richard.leitner@linux.dev> # i.MX8MP
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>

diff --git a/drivers/media/platform/nxp/imx8-isi/imx8-isi-video.c b/drivers/media/platform/nxp/imx8-isi/imx8-isi-video.c
index 8654150728a8692b480cfbfebdc0f2596c172a00..042b554d2775a9459a03a6c9e6901f326ea25f6d 100644 (file)
--- a/drivers/media/platform/nxp/imx8-isi/imx8-isi-video.c
+++ b/drivers/media/platform/nxp/imx8-isi/imx8-isi-video.c
@@ -937,6 +937,49 @@ static void mxc_isi_video_init_channel(struct mxc_isi_video *video)
        mxc_isi_channel_set_output_format(pipe, video->fmtinfo, &video->pix);
 }
 
+static int mxc_isi_vb2_prepare_streaming(struct vb2_queue *q)
+{
+       struct mxc_isi_video *video = vb2_get_drv_priv(q);
+       struct media_device *mdev = &video->pipe->isi->media_dev;
+       struct media_pipeline *pipe;
+       int ret;
+
+       /* Get a pipeline for the video node and start it. */
+       scoped_guard(mutex, &mdev->graph_mutex) {
+               ret = mxc_isi_pipe_acquire(video->pipe,
+                                          &mxc_isi_video_frame_write_done);
+               if (ret)
+                       return ret;
+
+               pipe = media_entity_pipeline(&video->vdev.entity)
+                    ? : &video->pipe->pipe;
+
+               ret = __video_device_pipeline_start(&video->vdev, pipe);
+               if (ret)
+                       goto err_release;
+       }
+
+       /* Verify that the video format matches the output of the subdev. */
+       ret = mxc_isi_video_validate_format(video);
+       if (ret)
+               goto err_stop;
+
+       /* Allocate buffers for discard operation. */
+       ret = mxc_isi_video_alloc_discard_buffers(video);
+       if (ret)
+               goto err_stop;
+
+       video->is_streaming = true;
+
+       return 0;
+
+err_stop:
+       video_device_pipeline_stop(&video->vdev);
+err_release:
+       mxc_isi_pipe_release(video->pipe);
+       return ret;
+}
+
 static int mxc_isi_vb2_start_streaming(struct vb2_queue *q, unsigned int count)
 {
        struct mxc_isi_video *video = vb2_get_drv_priv(q);
@@ -985,13 +1028,26 @@ static void mxc_isi_vb2_stop_streaming(struct vb2_queue *q)
        mxc_isi_video_return_buffers(video, VB2_BUF_STATE_ERROR);
 }
 
+static void mxc_isi_vb2_unprepare_streaming(struct vb2_queue *q)
+{
+       struct mxc_isi_video *video = vb2_get_drv_priv(q);
+
+       mxc_isi_video_free_discard_buffers(video);
+       video_device_pipeline_stop(&video->vdev);
+       mxc_isi_pipe_release(video->pipe);
+
+       video->is_streaming = false;
+}
+
 static const struct vb2_ops mxc_isi_vb2_qops = {
        .queue_setup            = mxc_isi_vb2_queue_setup,
        .buf_init               = mxc_isi_vb2_buffer_init,
        .buf_prepare            = mxc_isi_vb2_buffer_prepare,
        .buf_queue              = mxc_isi_vb2_buffer_queue,
+       .prepare_streaming      = mxc_isi_vb2_prepare_streaming,
        .start_streaming        = mxc_isi_vb2_start_streaming,
        .stop_streaming         = mxc_isi_vb2_stop_streaming,
+       .unprepare_streaming    = mxc_isi_vb2_unprepare_streaming,
 };
 
 /* -----------------------------------------------------------------------------
@@ -1145,97 +1201,6 @@ static int mxc_isi_video_s_fmt(struct file *file, void *priv,
        return 0;
 }
 
-static int mxc_isi_video_streamon(struct file *file, void *priv,
-                                 enum v4l2_buf_type type)
-{
-       struct mxc_isi_video *video = video_drvdata(file);
-       struct media_device *mdev = &video->pipe->isi->media_dev;
-       struct media_pipeline *pipe;
-       int ret;
-
-       if (vb2_queue_is_busy(&video->vb2_q, file))
-               return -EBUSY;
-
-       /*
-        * Get a pipeline for the video node and start it. This must be done
-        * here and not in the queue .start_streaming() handler, so that
-        * pipeline start errors can be reported from VIDIOC_STREAMON and not
-        * delayed until subsequent VIDIOC_QBUF calls.
-        */
-       mutex_lock(&mdev->graph_mutex);
-
-       ret = mxc_isi_pipe_acquire(video->pipe, &mxc_isi_video_frame_write_done);
-       if (ret) {
-               mutex_unlock(&mdev->graph_mutex);
-               return ret;
-       }
-
-       pipe = media_entity_pipeline(&video->vdev.entity) ? : &video->pipe->pipe;
-
-       ret = __video_device_pipeline_start(&video->vdev, pipe);
-       if (ret) {
-               mutex_unlock(&mdev->graph_mutex);
-               goto err_release;
-       }
-
-       mutex_unlock(&mdev->graph_mutex);
-
-       /* Verify that the video format matches the output of the subdev. */
-       ret = mxc_isi_video_validate_format(video);
-       if (ret)
-               goto err_stop;
-
-       /* Allocate buffers for discard operation. */
-       ret = mxc_isi_video_alloc_discard_buffers(video);
-       if (ret)
-               goto err_stop;
-
-       ret = vb2_streamon(&video->vb2_q, type);
-       if (ret)
-               goto err_free;
-
-       video->is_streaming = true;
-
-       return 0;
-
-err_free:
-       mxc_isi_video_free_discard_buffers(video);
-err_stop:
-       video_device_pipeline_stop(&video->vdev);
-err_release:
-       mxc_isi_pipe_release(video->pipe);
-       return ret;
-}
-
-static void mxc_isi_video_cleanup_streaming(struct mxc_isi_video *video)
-{
-       lockdep_assert_held(&video->lock);
-
-       if (!video->is_streaming)
-               return;
-
-       mxc_isi_video_free_discard_buffers(video);
-       video_device_pipeline_stop(&video->vdev);
-       mxc_isi_pipe_release(video->pipe);
-
-       video->is_streaming = false;
-}
-
-static int mxc_isi_video_streamoff(struct file *file, void *priv,
-                                  enum v4l2_buf_type type)
-{
-       struct mxc_isi_video *video = video_drvdata(file);
-       int ret;
-
-       ret = vb2_ioctl_streamoff(file, priv, type);
-       if (ret)
-               return ret;
-
-       mxc_isi_video_cleanup_streaming(video);
-
-       return 0;
-}
-
 static int mxc_isi_video_enum_framesizes(struct file *file, void *priv,
                                         struct v4l2_frmsizeenum *fsize)
 {
@@ -1291,9 +1256,8 @@ static const struct v4l2_ioctl_ops mxc_isi_video_ioctl_ops = {
        .vidioc_expbuf                  = vb2_ioctl_expbuf,
        .vidioc_prepare_buf             = vb2_ioctl_prepare_buf,
        .vidioc_create_bufs             = vb2_ioctl_create_bufs,
-
-       .vidioc_streamon                = mxc_isi_video_streamon,
-       .vidioc_streamoff               = mxc_isi_video_streamoff,
+       .vidioc_streamon                = vb2_ioctl_streamon,
+       .vidioc_streamoff               = vb2_ioctl_streamoff,
 
        .vidioc_enum_framesizes         = mxc_isi_video_enum_framesizes,
 
@@ -1332,10 +1296,6 @@ static int mxc_isi_video_release(struct file *file)
        if (ret)
                dev_err(video->pipe->isi->dev, "%s fail\n", __func__);
 
-       mutex_lock(&video->lock);
-       mxc_isi_video_cleanup_streaming(video);
-       mutex_unlock(&video->lock);
-
        pm_runtime_put(video->pipe->isi->dev);
        return ret;
 }