From 62dd4acd0bc8640ff2804bf8fda5baace266e95f Mon Sep 17 00:00:00 2001 From: Kevin Hilman Date: Wed, 7 Dec 2016 16:30:23 -0200 Subject: [PATCH] [media] davinci: vpif_capture: fix start/stop streaming locking 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, and update the irqlock comment to reflect what it actually protects. Suggested-by: Laurent Pinchart Reviewed-by: Laurent Pinchart Signed-off-by: Kevin Hilman Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/platform/davinci/vpif_capture.c | 6 +++--- drivers/media/platform/davinci/vpif_capture.h | 2 +- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/media/platform/davinci/vpif_capture.c b/drivers/media/platform/davinci/vpif_capture.c index 54c4397..44f7027 100644 --- a/drivers/media/platform/davinci/vpif_capture.c +++ b/drivers/media/platform/davinci/vpif_capture.c @@ -175,8 +175,6 @@ 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; @@ -207,6 +205,7 @@ 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 */ @@ -240,6 +239,7 @@ 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); @@ -283,7 +283,6 @@ 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); @@ -296,6 +295,7 @@ 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); diff --git a/drivers/media/platform/davinci/vpif_capture.h b/drivers/media/platform/davinci/vpif_capture.h index e625d1c..cf494a5 100644 --- a/drivers/media/platform/davinci/vpif_capture.h +++ b/drivers/media/platform/davinci/vpif_capture.h @@ -63,7 +63,7 @@ struct common_obj { struct vb2_queue buffer_queue; /* Queue of filled frames */ struct list_head dma_queue; - /* Used in video-buf */ + /* Protects the dma_queue field */ spinlock_t irqlock; /* lock used to access this structure */ struct mutex lock; -- 2.7.4