[PATCH v2 22/64] dmaengine: tegra20-apb: use channel BH helpers

Allen Pais <[email protected]> Mon, 27 Jul 2026 13:28:50 -0700
Newsgroups org.kernel.vger.linux-tegra,org.kernel.vger.dmaengine,org.kernel.vger.linux-kernel
Message-ID <5217cae9e0ebd8e828eec764ddd0844955475719.1785183549.git.allen.lkml@gmail.com>
Switch the per-channel tasklet to dma_chan_*_bh so completion handling
runs through the shared per-channel deferral mechanism.

Signed-off-by: Allen Pais <[email protected]>
---
 drivers/dma/tegra20-apb-dma.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c
index 640b8a218c9a..de15b8d3e8cb 100644
--- a/drivers/dma/tegra20-apb-dma.c
+++ b/drivers/dma/tegra20-apb-dma.c
@@ -194,9 +194,8 @@ struct tegra_dma_channel {
 	struct list_head	free_dma_desc;
 	struct list_head	cb_desc;
 
-	/* ISR handler and tasklet for bottom half of isr handling */
+	/* ISR handler for bottom-half processing */
 	dma_isr_handler		isr_handler;
-	struct tasklet_struct	tasklet;
 
 	/* Channel-slave specific configuration */
 	unsigned int slave_id;
@@ -632,9 +631,10 @@ static void handle_cont_sngl_cycle_dma_done(struct tegra_dma_channel *tdc,
 	}
 }
 
-static void tegra_dma_tasklet(struct tasklet_struct *t)
+static void tegra_dma_tasklet(struct dma_chan *chan)
 {
-	struct tegra_dma_channel *tdc = from_tasklet(tdc, t, tasklet);
+	struct tegra_dma_channel *tdc = container_of(chan, struct tegra_dma_channel,
+						     dma_chan);
 	struct dmaengine_desc_callback cb;
 	struct tegra_dma_desc *dma_desc;
 	unsigned int cb_count;
@@ -670,7 +670,7 @@ static irqreturn_t tegra_dma_isr(int irq, void *dev_id)
 	if (status & TEGRA_APBDMA_STATUS_ISE_EOC) {
 		tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status);
 		tdc->isr_handler(tdc, false);
-		tasklet_schedule(&tdc->tasklet);
+		dma_chan_schedule_bh(&tdc->dma_chan);
 		wake_up_all(&tdc->wq);
 		spin_unlock(&tdc->lock);
 		return IRQ_HANDLED;
@@ -819,7 +819,7 @@ static void tegra_dma_synchronize(struct dma_chan *dc)
 	 */
 	wait_event(tdc->wq, tegra_dma_eoc_interrupt_deasserted(tdc));
 
-	tasklet_kill(&tdc->tasklet);
+	dma_chan_kill_bh(&tdc->dma_chan);
 
 	pm_runtime_put(tdc->tdma->dev);
 }
@@ -1317,7 +1317,7 @@ static void tegra_dma_free_chan_resources(struct dma_chan *dc)
 	dev_dbg(tdc2dev(tdc), "Freeing channel %d\n", tdc->id);
 
 	tegra_dma_terminate_all(dc);
-	tasklet_kill(&tdc->tasklet);
+	dma_chan_kill_bh(&tdc->dma_chan);
 
 	list_splice_init(&tdc->pending_sg_req, &sg_req_list);
 	list_splice_init(&tdc->free_sg_req, &sg_req_list);
@@ -1511,7 +1511,7 @@ static int tegra_dma_probe(struct platform_device *pdev)
 		tdc->id = i;
 		tdc->slave_id = TEGRA_APBDMA_SLAVE_ID_INVALID;
 
-		tasklet_setup(&tdc->tasklet, tegra_dma_tasklet);
+		dma_chan_init_bh(&tdc->dma_chan, tegra_dma_tasklet);
 		spin_lock_init(&tdc->lock);
 		init_waitqueue_head(&tdc->wq);
 
@@ -1617,7 +1617,7 @@ static int __maybe_unused tegra_dma_dev_suspend(struct device *dev)
 	for (i = 0; i < tdma->chip_data->nr_channels; i++) {
 		struct tegra_dma_channel *tdc = &tdma->channels[i];
 
-		tasklet_kill(&tdc->tasklet);
+		dma_chan_kill_bh(&tdc->dma_chan);
 
 		spin_lock_irqsave(&tdc->lock, flags);
 		busy = tdc->busy;
-- 
2.43.0