diff options
Diffstat (limited to 'drivers/media/platform/ti/cal/cal.c')
| -rw-r--r-- | drivers/media/platform/ti/cal/cal.c | 31 |
1 files changed, 27 insertions, 4 deletions
diff --git a/drivers/media/platform/ti/cal/cal.c b/drivers/media/platform/ti/cal/cal.c index 910ff179e597..56b61c0583cf 100644 --- a/drivers/media/platform/ti/cal/cal.c +++ b/drivers/media/platform/ti/cal/cal.c @@ -717,11 +717,34 @@ static inline void cal_irq_wdma_end(struct cal_ctx *ctx) static void cal_irq_handle_wdma(struct cal_ctx *ctx, bool start, bool end) { - if (end) - cal_irq_wdma_end(ctx); + /* + * CAL HW interrupts are inherently racy. If we get both start and end + * interrupts, we don't know what has happened: did the DMA for a single + * frame start and end, or did one frame end and a new frame start? + * + * Usually for normal pixel frames we get the interrupts separately. If + * we do get both, we have to guess. The assumption in the code below is + * that the active vertical area is larger than the blanking vertical + * area, and thus it is more likely that we get the end of the old frame + * and the start of a new frame. + * + * However, for embedded data, which is only a few lines high, we always + * get both interrupts. Here the assumption is that we get both for the + * same frame. + */ + if (ctx->v_fmt.fmt.pix.height < 10) { + if (start) + cal_irq_wdma_start(ctx); - if (start) - cal_irq_wdma_start(ctx); + if (end) + cal_irq_wdma_end(ctx); + } else { + if (end) + cal_irq_wdma_end(ctx); + + if (start) + cal_irq_wdma_start(ctx); + } } static irqreturn_t cal_irq(int irq_cal, void *data) |