[PATCH v3 10/17] dma: qcom: bam_dma: Add support to initialize interconnect path

[Bhupesh Sharma]

From: Thara Gopinath <thara.gopinath@xxxxxxxxxx>

BAM dma engine associated with certain hardware blocks could require
relevant interconnect pieces be initialized prior to the dma engine
initialization. For e.g. crypto bam dma engine on sm8250. Such requirement
is passed on to the bam dma driver from dt via the "interconnects"
property.  Add support in bam_dma driver to check whether the interconnect
path is accessible/enabled prior to attempting driver intializations.

Cc: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Cc: Rob Herring <robh+dt@xxxxxxxxxx>
Cc: Andy Gross <agross@xxxxxxxxxx>
Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Cc: David S. Miller <davem@xxxxxxxxxxxxx>
Cc: Stephen Boyd <sboyd@xxxxxxxxxx>
Cc: Michael Turquette <mturquette@xxxxxxxxxxxx>
Cc: Vinod Koul <vkoul@xxxxxxxxxx>
Cc: dmaengine@xxxxxxxxxxxxxxx
Cc: linux-clk@xxxxxxxxxxxxxxx
Cc: linux-crypto@xxxxxxxxxxxxxxx
Cc: devicetree@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: bhupesh.linux@xxxxxxxxx
Signed-off-by: Thara Gopinath <thara.gopinath@xxxxxxxxxx>
[ bhupesh.sharma@xxxxxxxxxx: Make header file inclusion alphabetical and use devm_of_icc_get() ]
Signed-off-by: Bhupesh Sharma <bhupesh.sharma@xxxxxxxxxx>
---
 drivers/dma/qcom/bam_dma.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c
index c8a77b428b52..4b03415b8183 100644
--- a/drivers/dma/qcom/bam_dma.c
+++ b/drivers/dma/qcom/bam_dma.c
@@ -26,6 +26,7 @@
 #include <linux/kernel.h>
 #include <linux/io.h>
 #include <linux/init.h>
+#include <linux/interconnect.h>
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <linux/interrupt.h>
@@ -392,6 +393,7 @@ struct bam_device {
 	const struct reg_offset_data *layout;
 
 	struct clk *bamclk;
+	struct icc_path *mem_path;
 	int irq;
 
 	/* dma start transaction tasklet */
@@ -1284,6 +1286,14 @@ static int bam_dma_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	/* Ensure that interconnects are initialized */
+	bdev->mem_path = devm_of_icc_get(bdev->dev, "memory");
+	if (IS_ERR(bdev->mem_path)) {
+		ret = PTR_ERR(bdev->mem_path);
+		dev_err(bdev->dev, "failed to acquire icc path %d\n", ret);
+		goto err_disable_clk;
+	}
+
 	ret = bam_init(bdev);
 	if (ret)
 		goto err_disable_clk;
-- 
2.31.1