intel_mid_dma: Allow IRQ sharing

intel_mid_dma driver allows interrupt sharing. Thus it needs
to check whether IRQ source is the DMA controller and return
the appropriate IRQ return.

Signed-off-by: Yong Wang <yong.y.wang@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 14 insertions, 11 deletions

diff --git a/drivers/dma/intel_mid_dma.c b/drivers/dma/intel_mid_dma.c
index 373396c462a0..c4b81387f0c6 100644
--- a/drivers/dma/intel_mid_dma.c
+++ b/drivers/dma/intel_mid_dma.c
@@ -817,9 +817,14 @@ static void dma_tasklet2(unsigned long data)
 static irqreturn_t intel_mid_dma_interrupt(int irq, void *data)
 {
         struct middma_device *mid = data;
-        u32 status;
+        u32 tfr_status, err_status;
         int call_tasklet = 0;
 
+        tfr_status = ioread32(mid->dma_base + RAW_TFR);
+        err_status = ioread32(mid->dma_base + RAW_ERR);
+        if (!tfr_status && !err_status)
+                return IRQ_NONE;
+
         /*DMA Interrupt*/
         pr_debug("MDMA:Got an interrupt on irq %d\n", irq);
         if (!mid) {
@@ -827,19 +832,17 @@ static irqreturn_t intel_mid_dma_interrupt(int irq, void *data)
                 return -EINVAL;
         }
 
-        status = ioread32(mid->dma_base + RAW_TFR);
-        pr_debug("MDMA: Status %x, Mask %x\n", status, mid->intr_mask);
-        status &= mid->intr_mask;
-        if (status) {
+        pr_debug("MDMA: Status %x, Mask %x\n", tfr_status, mid->intr_mask);
+        tfr_status &= mid->intr_mask;
+        if (tfr_status) {
                 /*need to disable intr*/
-                iowrite32((status << 8), mid->dma_base + MASK_TFR);
-                pr_debug("MDMA: Calling tasklet %x\n", status);
+                iowrite32((tfr_status << 8), mid->dma_base + MASK_TFR);
+                pr_debug("MDMA: Calling tasklet %x\n", tfr_status);
                 call_tasklet = 1;
         }
-        status = ioread32(mid->dma_base + RAW_ERR);
-        status &= mid->intr_mask;
-        if (status) {
-                iowrite32(MASK_INTR_REG(status), mid->dma_base + MASK_ERR);
+        err_status &= mid->intr_mask;
+        if (err_status) {
+                iowrite32(MASK_INTR_REG(err_status), mid->dma_base + MASK_ERR);
                 call_tasklet = 1;
         }
         if (call_tasklet)