| Message ID | 20161207050826.23174-4-khilman@baylibre.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Kevin, Thank you for the patch. On Tuesday 06 Dec 2016 21:08:24 Kevin Hilman wrote: > Video capture subdevs may be over I2C and may sleep during xfer, so we > cannot do IRQ-disabled locking when calling the subdev. > > The IRQ-disabled locking is meant to protect the DMA queue list > throughout the rest of the driver, so update the locking in > [start|stop]_streaming to protect just this list. > > Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > Signed-off-by: Kevin Hilman <khilman@baylibre.com> I would also add a comment to document the irqlock field as protecting the dma_queue list only. Something like - /* Used in video-buf */ + /* Protects the dma_queue field */ spinlock_t irqlock; With that, Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > --- > drivers/media/platform/davinci/vpif_capture.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/media/platform/davinci/vpif_capture.c > b/drivers/media/platform/davinci/vpif_capture.c index > c24049acd40a..f72a719efb3d 100644 > --- a/drivers/media/platform/davinci/vpif_capture.c > +++ b/drivers/media/platform/davinci/vpif_capture.c > @@ -179,8 +179,6 @@ static int vpif_start_streaming(struct vb2_queue *vq, > unsigned int count) unsigned long addr, flags; > int ret; > > - spin_lock_irqsave(&common->irqlock, flags); > - > /* Initialize field_id */ > ch->field_id = 0; > > @@ -211,6 +209,7 @@ static int vpif_start_streaming(struct vb2_queue *vq, > unsigned int count) vpif_config_addr(ch, ret); > > /* Get the next frame from the buffer queue */ > + spin_lock_irqsave(&common->irqlock, flags); > common->cur_frm = common->next_frm = list_entry(common- >dma_queue.next, > struct vpif_cap_buffer, list); > /* Remove buffer from the buffer queue */ > @@ -244,6 +243,7 @@ static int vpif_start_streaming(struct vb2_queue *vq, > unsigned int count) return 0; > > err: > + spin_lock_irqsave(&common->irqlock, flags); > list_for_each_entry_safe(buf, tmp, &common->dma_queue, list) { > list_del(&buf->list); > vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_QUEUED); > @@ -287,7 +287,6 @@ static void vpif_stop_streaming(struct vb2_queue *vq) > vpif_dbg(1, debug, "stream off failed in subdev\n"); > > /* release all active buffers */ > - spin_lock_irqsave(&common->irqlock, flags); > if (common->cur_frm == common->next_frm) { > vb2_buffer_done(&common->cur_frm->vb.vb2_buf, > VB2_BUF_STATE_ERROR); > @@ -300,6 +299,7 @@ static void vpif_stop_streaming(struct vb2_queue *vq) > VB2_BUF_STATE_ERROR); > } > > + spin_lock_irqsave(&common->irqlock, flags); > while (!list_empty(&common->dma_queue)) { > common->next_frm = list_entry(common->dma_queue.next, > struct vpif_cap_buffer, list);
Laurent Pinchart <laurent.pinchart@ideasonboard.com> writes: > Hi Kevin, > > Thank you for the patch. > > On Tuesday 06 Dec 2016 21:08:24 Kevin Hilman wrote: >> Video capture subdevs may be over I2C and may sleep during xfer, so we >> cannot do IRQ-disabled locking when calling the subdev. >> >> The IRQ-disabled locking is meant to protect the DMA queue list >> throughout the rest of the driver, so update the locking in >> [start|stop]_streaming to protect just this list. >> >> Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> >> Signed-off-by: Kevin Hilman <khilman@baylibre.com> > > I would also add a comment to document the irqlock field as protecting the > dma_queue list only. Something like > > - /* Used in video-buf */ > + /* Protects the dma_queue field */ > spinlock_t irqlock; > > With that, > > Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> OK, will update the comment. Thanks for the review, Kevin -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/media/platform/davinci/vpif_capture.c b/drivers/media/platform/davinci/vpif_capture.c index c24049acd40a..f72a719efb3d 100644 --- a/drivers/media/platform/davinci/vpif_capture.c +++ b/drivers/media/platform/davinci/vpif_capture.c @@ -179,8 +179,6 @@ static int vpif_start_streaming(struct vb2_queue *vq, unsigned int count) unsigned long addr, flags; int ret; - spin_lock_irqsave(&common->irqlock, flags); - /* Initialize field_id */ ch->field_id = 0; @@ -211,6 +209,7 @@ static int vpif_start_streaming(struct vb2_queue *vq, unsigned int count) vpif_config_addr(ch, ret); /* Get the next frame from the buffer queue */ + spin_lock_irqsave(&common->irqlock, flags); common->cur_frm = common->next_frm = list_entry(common->dma_queue.next, struct vpif_cap_buffer, list); /* Remove buffer from the buffer queue */ @@ -244,6 +243,7 @@ static int vpif_start_streaming(struct vb2_queue *vq, unsigned int count) return 0; err: + spin_lock_irqsave(&common->irqlock, flags); list_for_each_entry_safe(buf, tmp, &common->dma_queue, list) { list_del(&buf->list); vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_QUEUED); @@ -287,7 +287,6 @@ static void vpif_stop_streaming(struct vb2_queue *vq) vpif_dbg(1, debug, "stream off failed in subdev\n"); /* release all active buffers */ - spin_lock_irqsave(&common->irqlock, flags); if (common->cur_frm == common->next_frm) { vb2_buffer_done(&common->cur_frm->vb.vb2_buf, VB2_BUF_STATE_ERROR); @@ -300,6 +299,7 @@ static void vpif_stop_streaming(struct vb2_queue *vq) VB2_BUF_STATE_ERROR); } + spin_lock_irqsave(&common->irqlock, flags); while (!list_empty(&common->dma_queue)) { common->next_frm = list_entry(common->dma_queue.next, struct vpif_cap_buffer, list);
Video capture subdevs may be over I2C and may sleep during xfer, so we cannot do IRQ-disabled locking when calling the subdev. The IRQ-disabled locking is meant to protect the DMA queue list throughout the rest of the driver, so update the locking in [start|stop]_streaming to protect just this list. Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Kevin Hilman <khilman@baylibre.com> --- drivers/media/platform/davinci/vpif_capture.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)