[media] davinci: vpif: add check for genuine interrupts in the isr

As the same interrupt is shared between capture and display devices,
sometimes we get isr calls where the interrupt might not genuinely belong
to capture or display. Hence, add a condition in the isr to check for
interrupt ownership and channel number to make sure we do not
service wrong interrupts.

Signed-off-by: Manjunath Hadli <manjunath.hadli@ti.com>
Signed-off-by: Lad, Prabhakar <prabhakar.lad@ti.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/davinci/vpif.h

@@ -569,6 +569,21 @@ static inline void ch3_set_vbi_addr(unsigned long top_strt_luma,
 	regw(btm_strt_luma, VPIF_CH3_BTM_STRT_ADD_VANC);
 }
 
+static inline int vpif_intr_status(int channel)
+{
+	int status = 0;
+	int mask;
+
+	if (channel < 0 || channel > 3)
+		return 0;
+
+	mask = 1 << channel;
+	status = regr(VPIF_STATUS) & mask;
+	regw(status, VPIF_STATUS_CLR);
+
+	return status;
+}
+
 #define VPIF_MAX_NAME	(30)
 
 /* This structure will store size parameters as per the mode selected by user */

drivers/media/video/davinci/vpif_capture.c

@@ -341,6 +341,9 @@ static irqreturn_t vpif_channel_isr(int irq, void *dev_id)
 	int fid = -1, i;
 
 	channel_id = *(int *)(dev_id);
+	if (!vpif_intr_status(channel_id))
+		return IRQ_NONE;
+
 	ch = dev->dev[channel_id];
 
 	field = ch->common[VPIF_VIDEO_INDEX].fmt.fmt.pix.field;

drivers/media/video/davinci/vpif_display.c

@@ -307,6 +307,9 @@ static irqreturn_t vpif_channel_isr(int irq, void *dev_id)
 	int channel_id = 0;
 
 	channel_id = *(int *)(dev_id);
+	if (!vpif_intr_status(channel_id + 2))
+		return IRQ_NONE;
+
 	ch = dev->dev[channel_id];
 	field = ch->common[VPIF_VIDEO_INDEX].fmt.fmt.pix.field;
 	for (i = 0; i < VPIF_NUMOBJECTS; i++) {