wcte43x, wcte13xp, wcaxx: Bump irqmisses counter when there are DMA underruns.

This makes the behavior of IRQ misses for these drivers behave the same as the
wcte12xp, wctdm24xxp, and wct4xxp drivers.

Previously irqmisses would never increase. The presence of underruns would still
show up in dmesg as latency bumps.

Signed-off-by: Shaun Ruffell <sruffell@digium.com>
Signed-off-by: Russ Meyerriecks <rmeyerriecks@digium.com>

drivers/dahdi/wcaxx-base.c

@@ -3864,9 +3864,16 @@ static void wcaxx_back_out_gracefully(struct wcaxx *wc)
 	kfree(wc);
 }
 
+static void wcaxx_handle_error(struct wcxb *xb)
+{
+	struct wcaxx *wc = container_of(xb, struct wcaxx, xb);
+	wc->ddev->irqmisses++;
+}
+
 static const struct wcxb_operations wcxb_operations = {
 	.handle_receive = wcaxx_handle_receive,
 	.handle_transmit = wcaxx_handle_transmit,
+	.handle_error = wcaxx_handle_error,
 };
 
 struct cmd_results {

drivers/dahdi/wcte13xp-base.c

@@ -115,10 +115,17 @@ static void te13x_handle_transmit(struct wcxb *xb, void *vfp);
 static void te13x_handle_receive(struct wcxb *xb, void *vfp);
 static void te13x_handle_interrupt(struct wcxb *xb, u32 pending);
 
+static void te13x_handle_error(struct wcxb *xb)
+{
+	struct t13x *wc = container_of(xb, struct t13x, xb);
+	wc->ddev->irqmisses++;
+}
+
 static struct wcxb_operations xb_ops = {
 	.handle_receive = te13x_handle_receive,
 	.handle_transmit = te13x_handle_transmit,
 	.handle_interrupt = te13x_handle_interrupt,
+	.handle_error = te13x_handle_error,
 };
 
 /* Maintenance Mode Registers */

drivers/dahdi/wcte43x-base.c

@@ -144,10 +144,17 @@ static void t43x_handle_transmit(struct wcxb *xb, void *vfp);
 static void t43x_handle_receive(struct wcxb *xb, void *vfp);
 static void t43x_handle_interrupt(struct wcxb *xb, u32 pending);
 
+static void t43x_handle_error(struct wcxb *xb)
+{
+	struct t43x *wc = container_of(xb, struct t43x, xb);
+	wc->ddev->irqmisses++;
+}
+
 static struct wcxb_operations xb_ops = {
 	.handle_receive = t43x_handle_receive,
 	.handle_transmit = t43x_handle_transmit,
 	.handle_interrupt = t43x_handle_interrupt,
+	.handle_error = t43x_handle_error,
 };
 
 /* Maintenance Mode Registers */

drivers/dahdi/wcxb.c

@@ -397,6 +397,12 @@ static irqreturn_t _wcxb_isr(int irq, void *dev_id)
 		if (pending & DESC_UNDERRUN) {
 			u32 reg;
 
+			/* Report the error in case drivers have any custom
+			 * methods for indicating potential data corruption. An
+			 * underrun means data loss in the TDM channel. */
+			if (xb->ops->handle_error)
+				xb->ops->handle_error(xb);
+
 			/* bump latency */
 			spin_lock(&xb->lock);