Merge branch 'fix/edma' into fixes

Vinod Koul · Vinod Koul · commit 956e6c8e18fa · 2016-04-16T22:52:03.000+05:30
diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c
@@ -1238,6 +1238,7 @@ static struct dma_async_tx_descriptor *edma_prep_dma_cyclic(
 	struct edma_desc *edesc;
 	dma_addr_t src_addr, dst_addr;
 	enum dma_slave_buswidth dev_width;
+	bool use_intermediate = false;
 	u32 burst;
 	int i, ret, nslots;
 
@@ -1279,8 +1280,21 @@ static struct dma_async_tx_descriptor *edma_prep_dma_cyclic(
 	 * but the synchronization is difficult to achieve with Cyclic and
 	 * cannot be guaranteed, so we error out early.
 	 */
-	if (nslots > MAX_NR_SG)
-		return NULL;
+	if (nslots > MAX_NR_SG) {
+		/*
+		 * If the burst and period sizes are the same, we can put
+		 * the full buffer into a single period and activate
+		 * intermediate interrupts. This will produce interrupts
+		 * after each burst, which is also after each desired period.
+		 */
+		if (burst == period_len) {
+			period_len = buf_len;
+			nslots = 2;
+			use_intermediate = true;
+		} else {
+			return NULL;
+		}
+	}
 
 	edesc = kzalloc(sizeof(*edesc) + nslots * sizeof(edesc->pset[0]),
 			GFP_ATOMIC);
@@ -1358,8 +1372,13 @@ static struct dma_async_tx_descriptor *edma_prep_dma_cyclic(
 		/*
 		 * Enable period interrupt only if it is requested
 		 */
-		if (tx_flags & DMA_PREP_INTERRUPT)
+		if (tx_flags & DMA_PREP_INTERRUPT) {
 			edesc->pset[i].param.opt |= TCINTEN;
+
+			/* Also enable intermediate interrupts if necessary */
+			if (use_intermediate)
+				edesc->pset[i].param.opt |= ITCINTEN;
+		}
 	}
 
 	/* Place the cyclic channel to highest priority queue */
@@ -1570,32 +1589,6 @@ static irqreturn_t dma_ccerr_handler(int irq, void *data)
 	return IRQ_HANDLED;
 }
 
-static void edma_tc_set_pm_state(struct edma_tc *tc, bool enable)
-{
-	struct platform_device *tc_pdev;
-	int ret;
-
-	if (!IS_ENABLED(CONFIG_OF) || !tc)
-		return;
-
-	tc_pdev = of_find_device_by_node(tc->node);
-	if (!tc_pdev) {
-		pr_err("%s: TPTC device is not found\n", __func__);
-		return;
-	}
-	if (!pm_runtime_enabled(&tc_pdev->dev))
-		pm_runtime_enable(&tc_pdev->dev);
-
-	if (enable)
-		ret = pm_runtime_get_sync(&tc_pdev->dev);
-	else
-		ret = pm_runtime_put_sync(&tc_pdev->dev);
-
-	if (ret < 0)
-		pr_err("%s: pm_runtime_%s_sync() failed for %s\n", __func__,
-		       enable ? "get" : "put", dev_name(&tc_pdev->dev));
-}
-
 /* Alloc channel resources */
 static int edma_alloc_chan_resources(struct dma_chan *chan)
 {
@@ -1632,8 +1625,6 @@ static int edma_alloc_chan_resources(struct dma_chan *chan)
 		EDMA_CHAN_SLOT(echan->ch_num), chan->chan_id,
 		echan->hw_triggered ? "HW" : "SW");
 
-	edma_tc_set_pm_state(echan->tc, true);
-
 	return 0;
 
 err_slot:
@@ -1670,7 +1661,6 @@ static void edma_free_chan_resources(struct dma_chan *chan)
 		echan->alloced = false;
 	}
 
-	edma_tc_set_pm_state(echan->tc, false);
 	echan->tc = NULL;
 	echan->hw_triggered = false;
 
@@ -2417,10 +2407,8 @@ static int edma_pm_suspend(struct device *dev)
 	int i;
 
 	for (i = 0; i < ecc->num_channels; i++) {
-		if (echan[i].alloced) {
+		if (echan[i].alloced)
 			edma_setup_interrupt(&echan[i], false);
-			edma_tc_set_pm_state(echan[i].tc, false);
-		}
 	}
 
 	return 0;
@@ -2450,8 +2438,6 @@ static int edma_pm_resume(struct device *dev)
 
 			/* Set up channel -> slot mapping for the entry slot */
 			edma_set_chmap(&echan[i], echan[i].slot[0]);
-
-			edma_tc_set_pm_state(echan[i].tc, true);
 		}
 	}
 
@@ -2475,7 +2461,8 @@ static struct platform_driver edma_driver = {
 
 static int edma_tptc_probe(struct platform_device *pdev)
 {
-	return 0;
+	pm_runtime_enable(&pdev->dev);
+	return pm_runtime_get_sync(&pdev->dev);
 }
 
 static struct platform_driver edma_tptc_driver = {
