Em Sat, 4 Aug 2018 14:45:22 +0200
Hans Verkuil <hverkuil@xxxxxxxxx> escreveu:
> From: Hans Verkuil <hans.verkuil@xxxxxxxxx>
>
> v4l2_ctrl uses mutexes, so we can't setup a ctrl_handler in
> interrupt context. Switch to a workqueue instead and drop the timer.
>
> Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx>
Shouldn't this come earlier at the series (before adding request API
support to m2m) in order to avoid regressions?
> ---
> drivers/media/platform/vim2m.c | 25 ++++++++++---------------
> 1 file changed, 10 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/media/platform/vim2m.c b/drivers/media/platform/vim2m.c
> index 462099a141e4..6f87ef025ff1 100644
> --- a/drivers/media/platform/vim2m.c
> +++ b/drivers/media/platform/vim2m.c
> @@ -3,7 +3,8 @@
> *
> * This is a virtual device driver for testing mem-to-mem videobuf framework.
> * It simulates a device that uses memory buffers for both source and
> - * destination, processes the data and issues an "irq" (simulated by a timer).
> + * destination, processes the data and issues an "irq" (simulated by a delayed
> + * workqueue).
> * The device is capable of multi-instance, multi-buffer-per-transaction
> * operation (via the mem2mem framework).
> *
> @@ -19,7 +20,6 @@
> #include <linux/module.h>
> #include <linux/delay.h>
> #include <linux/fs.h>
> -#include <linux/timer.h>
> #include <linux/sched.h>
> #include <linux/slab.h>
>
> @@ -148,7 +148,7 @@ struct vim2m_dev {
> struct mutex dev_mutex;
> spinlock_t irqlock;
>
> - struct timer_list timer;
> + struct delayed_work work_run;
>
> struct v4l2_m2m_dev *m2m_dev;
> };
> @@ -336,12 +336,6 @@ static int device_process(struct vim2m_ctx *ctx,
> return 0;
> }
>
> -static void schedule_irq(struct vim2m_dev *dev, int msec_timeout)
> -{
> - dprintk(dev, "Scheduling a simulated irq\n");
> - mod_timer(&dev->timer, jiffies + msecs_to_jiffies(msec_timeout));
> -}
> -
> /*
> * mem2mem callbacks
> */
> @@ -387,13 +381,14 @@ static void device_run(void *priv)
>
> device_process(ctx, src_buf, dst_buf);
>
> - /* Run a timer, which simulates a hardware irq */
> - schedule_irq(dev, ctx->transtime);
> + /* Run delayed work, which simulates a hardware irq */
> + schedule_delayed_work(&dev->work_run, msecs_to_jiffies(ctx->transtime));
> }
>
> -static void device_isr(struct timer_list *t)
> +static void device_work(struct work_struct *w)
> {
> - struct vim2m_dev *vim2m_dev = from_timer(vim2m_dev, t, timer);
> + struct vim2m_dev *vim2m_dev =
> + container_of(w, struct vim2m_dev, work_run.work);
> struct vim2m_ctx *curr_ctx;
> struct vb2_v4l2_buffer *src_vb, *dst_vb;
> unsigned long flags;
> @@ -805,6 +800,7 @@ static void vim2m_stop_streaming(struct vb2_queue *q)
> struct vb2_v4l2_buffer *vbuf;
> unsigned long flags;
>
> + flush_scheduled_work();
> for (;;) {
> if (V4L2_TYPE_IS_OUTPUT(q->type))
> vbuf = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx);
> @@ -1015,6 +1011,7 @@ static int vim2m_probe(struct platform_device *pdev)
> vfd = &dev->vfd;
> vfd->lock = &dev->dev_mutex;
> vfd->v4l2_dev = &dev->v4l2_dev;
> + INIT_DELAYED_WORK(&dev->work_run, device_work);
>
> ret = video_register_device(vfd, VFL_TYPE_GRABBER, 0);
> if (ret) {
> @@ -1026,7 +1023,6 @@ static int vim2m_probe(struct platform_device *pdev)
> v4l2_info(&dev->v4l2_dev,
> "Device registered as /dev/video%d\n", vfd->num);
>
> - timer_setup(&dev->timer, device_isr, 0);
> platform_set_drvdata(pdev, dev);
>
> dev->m2m_dev = v4l2_m2m_init(&m2m_ops);
> @@ -1083,7 +1079,6 @@ static int vim2m_remove(struct platform_device *pdev)
> media_device_cleanup(&dev->mdev);
> #endif
> v4l2_m2m_release(dev->m2m_dev);
> - del_timer_sync(&dev->timer);
> video_unregister_device(&dev->vfd);
> v4l2_device_unregister(&dev->v4l2_dev);
>
Thanks,
Mauro
