[PATCH 08/18] dmaengine: bcm2835: pass dma_chan to generic functions

Dave Stevenson dave.stevenson at raspberrypi.com
Fri May 24 11:26:52 PDT 2024


From: Stefan Wahren <stefan.wahren at i2se.com>

In preparation to support more platforms pass the dma_chan to the
generic functions. This provides access to the DMA device and possible
platform specific data.

Signed-off-by: Stefan Wahren <wahrenst at gmx.net>
Signed-off-by: Dave Stevenson <dave.stevenson at raspberrypi.com>
---
 drivers/dma/bcm2835-dma.c | 24 ++++++++++++++----------
 1 file changed, 14 insertions(+), 10 deletions(-)

diff --git a/drivers/dma/bcm2835-dma.c b/drivers/dma/bcm2835-dma.c
index e2f9c8692e6b..aefaa1f01d7f 100644
--- a/drivers/dma/bcm2835-dma.c
+++ b/drivers/dma/bcm2835-dma.c
@@ -288,12 +288,13 @@ static void bcm2835_dma_desc_free(struct virt_dma_desc *vd)
 }
 
 static bool
-bcm2835_dma_create_cb_set_length(struct bcm2835_chan *chan,
+bcm2835_dma_create_cb_set_length(struct dma_chan *chan,
 				 struct bcm2835_dma_cb *control_block,
 				 size_t len, size_t period_len,
 				 size_t *total_len)
 {
-	size_t max_len = bcm2835_dma_max_frame_length(chan);
+	struct bcm2835_chan *c = to_bcm2835_dma_chan(chan);
+	size_t max_len = bcm2835_dma_max_frame_length(c);
 
 	/* set the length taking lite-channel limitations into account */
 	control_block->length = min_t(u32, len, max_len);
@@ -417,7 +418,7 @@ static struct bcm2835_desc *bcm2835_dma_create_cb_chain(
 		/* set up length in control_block if requested */
 		if (buf_len) {
 			/* calculate length honoring period_length */
-			if (bcm2835_dma_create_cb_set_length(c, control_block,
+			if (bcm2835_dma_create_cb_set_length(chan, control_block,
 							     len, period_len,
 							     &total_len)) {
 				/* add extrainfo bits in info */
@@ -485,8 +486,9 @@ static void bcm2835_dma_fill_cb_chain_with_sg(
 	}
 }
 
-static void bcm2835_dma_abort(struct bcm2835_chan *c)
+static void bcm2835_dma_abort(struct dma_chan *chan)
 {
+	struct bcm2835_chan *c = to_bcm2835_dma_chan(chan);
 	void __iomem *chan_base = c->chan_base;
 	long int timeout = 10000;
 
@@ -513,8 +515,9 @@ static void bcm2835_dma_abort(struct bcm2835_chan *c)
 	writel(BCM2835_DMA_RESET, chan_base + BCM2835_DMA_CS);
 }
 
-static void bcm2835_dma_start_desc(struct bcm2835_chan *c)
+static void bcm2835_dma_start_desc(struct dma_chan *chan)
 {
+	struct bcm2835_chan *c = to_bcm2835_dma_chan(chan);
 	struct virt_dma_desc *vd = vchan_next_desc(&c->vc);
 	struct bcm2835_desc *d;
 
@@ -533,7 +536,8 @@ static void bcm2835_dma_start_desc(struct bcm2835_chan *c)
 
 static irqreturn_t bcm2835_dma_callback(int irq, void *data)
 {
-	struct bcm2835_chan *c = data;
+	struct dma_chan *chan = data;
+	struct bcm2835_chan *c = to_bcm2835_dma_chan(chan);
 	struct bcm2835_desc *d;
 	unsigned long flags;
 
@@ -566,7 +570,7 @@ static irqreturn_t bcm2835_dma_callback(int irq, void *data)
 			vchan_cyclic_callback(&d->vd);
 		} else if (!readl(c->chan_base + BCM2835_DMA_ADDR)) {
 			vchan_cookie_complete(&c->desc->vd);
-			bcm2835_dma_start_desc(c);
+			bcm2835_dma_start_desc(chan);
 		}
 	}
 
@@ -594,7 +598,7 @@ static int bcm2835_dma_alloc_chan_resources(struct dma_chan *chan)
 	}
 
 	return request_irq(c->irq_number, bcm2835_dma_callback,
-			   c->irq_flags, "DMA IRQ", c);
+			   c->irq_flags, "DMA IRQ", chan);
 }
 
 static void bcm2835_dma_free_chan_resources(struct dma_chan *chan)
@@ -682,7 +686,7 @@ static void bcm2835_dma_issue_pending(struct dma_chan *chan)
 
 	spin_lock_irqsave(&c->vc.lock, flags);
 	if (vchan_issue_pending(&c->vc) && !c->desc)
-		bcm2835_dma_start_desc(c);
+		bcm2835_dma_start_desc(chan);
 
 	spin_unlock_irqrestore(&c->vc.lock, flags);
 }
@@ -846,7 +850,7 @@ static int bcm2835_dma_terminate_all(struct dma_chan *chan)
 	if (c->desc) {
 		vchan_terminate_vdesc(&c->desc->vd);
 		c->desc = NULL;
-		bcm2835_dma_abort(c);
+		bcm2835_dma_abort(chan);
 	}
 
 	vchan_get_all_descriptors(&c->vc, &head);
-- 
2.34.1




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