diff options
| -rw-r--r-- | drivers/media/video/pxa_camera.c | 25 |
1 files changed, 20 insertions, 5 deletions
diff --git a/drivers/media/video/pxa_camera.c b/drivers/media/video/pxa_camera.c index a2f98ec14d9..cfa113cedd3 100644 --- a/drivers/media/video/pxa_camera.c +++ b/drivers/media/video/pxa_camera.c @@ -624,6 +624,7 @@ static void pxa_camera_stop_capture(struct pxa_camera_dev *pcdev) cicr0 = __raw_readl(pcdev->base + CICR0) & ~CICR0_ENB; __raw_writel(cicr0, pcdev->base + CICR0); + pcdev->active = NULL; dev_dbg(pcdev->dev, "%s\n", __func__); } @@ -697,7 +698,6 @@ static void pxa_camera_wakeup(struct pxa_camera_dev *pcdev, if (list_empty(&pcdev->capture)) { pxa_camera_stop_capture(pcdev); - pcdev->active = NULL; for (i = 0; i < pcdev->channels; i++) pcdev->sg_tail[i] = NULL; return; @@ -765,10 +765,20 @@ static void pxa_camera_dma_irq(int channel, struct pxa_camera_dev *pcdev, goto out; } - if (!pcdev->active) { - dev_err(pcdev->dev, "DMA End IRQ with no active buffer!\n"); + /* + * pcdev->active should not be NULL in DMA irq handler. + * + * But there is one corner case : if capture was stopped due to an + * overrun of channel 1, and at that same channel 2 was completed. + * + * When handling the overrun in DMA irq for channel 1, we'll stop the + * capture and restart it (and thus set pcdev->active to NULL). But the + * DMA irq handler will already be pending for channel 2. So on entering + * the DMA irq handler for channel 2 there will be no active buffer, yet + * that is normal. + */ + if (!pcdev->active) goto out; - } vb = &pcdev->active->vb; buf = container_of(vb, struct pxa_buffer, vb); @@ -779,7 +789,12 @@ static void pxa_camera_dma_irq(int channel, struct pxa_camera_dev *pcdev, status & DCSR_ENDINTR ? "EOF " : "", vb, DDADR(channel)); if (status & DCSR_ENDINTR) { - if (camera_status & overrun) { + /* + * It's normal if the last frame creates an overrun, as there + * are no more DMA descriptors to fetch from QCI fifos + */ + if (camera_status & overrun && + !list_is_last(pcdev->capture.next, &pcdev->capture)) { dev_dbg(pcdev->dev, "FIFO overrun! CISR: %x\n", camera_status); pxa_camera_stop_capture(pcdev); |