[PATCH v2 21/64] dmaengine: zynqmp-dma: switch completion tasklet to dma_chan BH

[Allen Pais]

Replace the per-channel tasklet with the shared dma_chan BH helper.
The handler continues to run in softirq context while dmaengine owns
the common scheduling and teardown mechanism.

Signed-off-by: Allen Pais <allen.lkml at gmail.com>
---
 drivers/dma/xilinx/zynqmp_dma.c | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/drivers/dma/xilinx/zynqmp_dma.c b/drivers/dma/xilinx/zynqmp_dma.c
index f6a812e49ddc..6291126cdc9f 100644
--- a/drivers/dma/xilinx/zynqmp_dma.c
+++ b/drivers/dma/xilinx/zynqmp_dma.c
@@ -207,7 +207,6 @@ struct zynqmp_dma_desc_sw {
  * @dev: The dma device
  * @irq: Channel IRQ
  * @is_dmacoherent: Tells whether dma operations are coherent or not
- * @tasklet: Cleanup work after irq
  * @idle : Channel status;
  * @desc_size: Size of the low level descriptor
  * @err: Channel has errors
@@ -232,7 +231,6 @@ struct zynqmp_dma_chan {
 	struct device *dev;
 	int irq;
 	bool is_dmacoherent;
-	struct tasklet_struct tasklet;
 	bool idle;
 	size_t desc_size;
 	bool err;
@@ -735,7 +733,7 @@ static irqreturn_t zynqmp_dma_irq_handler(int irq, void *data)
 
 	writel(isr, chan->regs + ZYNQMP_DMA_ISR);
 	if (status & ZYNQMP_DMA_INT_DONE) {
-		tasklet_schedule(&chan->tasklet);
+		dma_chan_schedule_bh(&chan->common);
 		ret = IRQ_HANDLED;
 	}
 
@@ -744,7 +742,7 @@ static irqreturn_t zynqmp_dma_irq_handler(int irq, void *data)
 
 	if (status & ZYNQMP_DMA_INT_ERR) {
 		chan->err = true;
-		tasklet_schedule(&chan->tasklet);
+		dma_chan_schedule_bh(&chan->common);
 		dev_err(chan->dev, "Channel %p has errors\n", chan);
 		ret = IRQ_HANDLED;
 	}
@@ -760,11 +758,12 @@ static irqreturn_t zynqmp_dma_irq_handler(int irq, void *data)
 
 /**
  * zynqmp_dma_do_tasklet - Schedule completion tasklet
- * @t: Pointer to the ZynqMP DMA channel structure
+ * @c: Pointer to the ZynqMP DMA channel structure
  */
-static void zynqmp_dma_do_tasklet(struct tasklet_struct *t)
+static void zynqmp_dma_do_tasklet(struct dma_chan *c)
 {
-	struct zynqmp_dma_chan *chan = from_tasklet(chan, t, tasklet);
+	struct zynqmp_dma_chan *chan = container_of(c,
+			struct zynqmp_dma_chan, common);
 	u32 count;
 	unsigned long irqflags;
 
@@ -815,7 +814,7 @@ static void zynqmp_dma_synchronize(struct dma_chan *dchan)
 {
 	struct zynqmp_dma_chan *chan = to_chan(dchan);
 
-	tasklet_kill(&chan->tasklet);
+	dma_chan_kill_bh(&chan->common);
 }
 
 /**
@@ -887,7 +886,7 @@ static void zynqmp_dma_chan_remove(struct zynqmp_dma_chan *chan)
 
 	if (chan->irq)
 		devm_free_irq(chan->zdev->dev, chan->irq, chan);
-	tasklet_kill(&chan->tasklet);
+	dma_chan_kill_bh(&chan->common);
 	list_del(&chan->common.device_node);
 }
 
@@ -937,7 +936,7 @@ static int zynqmp_dma_chan_probe(struct zynqmp_dma_device *zdev,
 
 	chan->is_dmacoherent =  of_property_read_bool(node, "dma-coherent");
 	zdev->chan = chan;
-	tasklet_setup(&chan->tasklet, zynqmp_dma_do_tasklet);
+	dma_chan_init_bh(&chan->common, zynqmp_dma_do_tasklet);
 	spin_lock_init(&chan->lock);
 	INIT_LIST_HEAD(&chan->active_list);
 	INIT_LIST_HEAD(&chan->pending_list);
-- 
2.43.0