[PATCH 4/9] probe/dma/qcom-bam: removed redundant code from qcom bam dma controller's probe function

[Satendra Singh Thakur <sst2005@gmail.com>]

1. In order to remove duplicate code, following functions:
platform_get_resource
devm_kzalloc
devm_ioremap_resource
devm_clk_get
platform_get_irq
clk_prepare_enable
are replaced with a macro devm_platform_probe_helper_clk.

2. Renamed variables regs and bamclk so that helper macro can
be applied.

3. This patch depends on the file include/linux/probe-helper.h
which is pushed in previous patch [01/09].

Signed-off-by: Satendra Singh Thakur <satendrasingh.thakur@hcl.com>
Signed-off-by: Satendra Singh Thakur <sst2005@gmail.com>
---
 drivers/dma/qcom/bam_dma.c | 71 ++++++++++++++++----------------------
 1 file changed, 29 insertions(+), 42 deletions(-)

diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c
index 8e90a405939d..06c136ca8e40 100644
--- a/drivers/dma/qcom/bam_dma.c
+++ b/drivers/dma/qcom/bam_dma.c
@@ -41,6 +41,7 @@
 #include <linux/clk.h>
 #include <linux/dmaengine.h>
 #include <linux/pm_runtime.h>
+#include <linux/probe-helper.h>
 
 #include "../dmaengine.h"
 #include "../virt-dma.h"
@@ -378,7 +379,7 @@ static inline struct bam_chan *to_bam_chan(struct dma_chan *common)
 }
 
 struct bam_device {
-	void __iomem *regs;
+	void __iomem *base;
 	struct device *dev;
 	struct dma_device common;
 	struct device_dma_parameters dma_parms;
@@ -392,7 +393,7 @@ struct bam_device {
 
 	const struct reg_offset_data *layout;
 
-	struct clk *bamclk;
+	struct clk *clk;
 	int irq;
 
 	/* dma start transaction tasklet */
@@ -410,7 +411,7 @@ static inline void __iomem *bam_addr(struct bam_device *bdev, u32 pipe,
 {
 	const struct reg_offset_data r = bdev->layout[reg];
 
-	return bdev->regs + r.base_offset +
+	return bdev->base + r.base_offset +
 		r.pipe_mult * pipe +
 		r.evnt_mult * pipe +
 		r.ee_mult * bdev->ee;
@@ -1209,41 +1210,41 @@ static int bam_dma_probe(struct platform_device *pdev)
 {
 	struct bam_device *bdev;
 	const struct of_device_id *match;
-	struct resource *iores;
 	int ret, i;
-
-	bdev = devm_kzalloc(&pdev->dev, sizeof(*bdev), GFP_KERNEL);
-	if (!bdev)
-		return -ENOMEM;
+	/*
+	 * This macro internally combines following functions:
+	 * devm_kzalloc, platform_get_resource, devm_ioremap_resource,
+	 * devm_clk_get, platform_get_irq, clk_prepare_enable
+	 */
+	ret = devm_platform_probe_helper_clk(pdev, bdev, "bam_clk");
+	bdev->controlled_remotely = of_property_read_bool(pdev->dev.of_node,
+						"qcom,controlled-remotely");
+	if (ret < 0) {
+		if (IS_ERR(bdev->clk)) {
+			if (!bdev->controlled_remotely)
+				return ret;
+			bdev->clk = NULL;
+		} else
+			return ret;
+	}
 
 	bdev->dev = &pdev->dev;
 
 	match = of_match_node(bam_of_match, pdev->dev.of_node);
 	if (!match) {
 		dev_err(&pdev->dev, "Unsupported BAM module\n");
-		return -ENODEV;
+		ret = -ENODEV;
+		goto err_disable_clk;
 	}
 
 	bdev->layout = match->data;
 
-	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	bdev->regs = devm_ioremap_resource(&pdev->dev, iores);
-	if (IS_ERR(bdev->regs))
-		return PTR_ERR(bdev->regs);
-
-	bdev->irq = platform_get_irq(pdev, 0);
-	if (bdev->irq < 0)
-		return bdev->irq;
-
 	ret = of_property_read_u32(pdev->dev.of_node, "qcom,ee", &bdev->ee);
 	if (ret) {
 		dev_err(bdev->dev, "Execution environment unspecified\n");
-		return ret;
+		goto err_disable_clk;
 	}
 
-	bdev->controlled_remotely = of_property_read_bool(pdev->dev.of_node,
-						"qcom,controlled-remotely");
-
 	if (bdev->controlled_remotely) {
 		ret = of_property_read_u32(pdev->dev.of_node, "num-channels",
 					   &bdev->num_channels);
@@ -1256,20 +1257,6 @@ static int bam_dma_probe(struct platform_device *pdev)
 			dev_err(bdev->dev, "num-ees unspecified in dt\n");
 	}
 
-	bdev->bamclk = devm_clk_get(bdev->dev, "bam_clk");
-	if (IS_ERR(bdev->bamclk)) {
-		if (!bdev->controlled_remotely)
-			return PTR_ERR(bdev->bamclk);
-
-		bdev->bamclk = NULL;
-	}
-
-	ret = clk_prepare_enable(bdev->bamclk);
-	if (ret) {
-		dev_err(bdev->dev, "failed to prepare/enable clock\n");
-		return ret;
-	}
-
 	ret = bam_init(bdev);
 	if (ret)
 		goto err_disable_clk;
@@ -1359,7 +1346,7 @@ static int bam_dma_probe(struct platform_device *pdev)
 err_tasklet_kill:
 	tasklet_kill(&bdev->task);
 err_disable_clk:
-	clk_disable_unprepare(bdev->bamclk);
+	clk_disable_unprepare(bdev->clk);
 
 	return ret;
 }
@@ -1393,7 +1380,7 @@ static int bam_dma_remove(struct platform_device *pdev)
 
 	tasklet_kill(&bdev->task);
 
-	clk_disable_unprepare(bdev->bamclk);
+	clk_disable_unprepare(bdev->clk);
 
 	return 0;
 }
@@ -1402,7 +1389,7 @@ static int __maybe_unused bam_dma_runtime_suspend(struct device *dev)
 {
 	struct bam_device *bdev = dev_get_drvdata(dev);
 
-	clk_disable(bdev->bamclk);
+	clk_disable(bdev->clk);
 
 	return 0;
 }
@@ -1412,7 +1399,7 @@ static int __maybe_unused bam_dma_runtime_resume(struct device *dev)
 	struct bam_device *bdev = dev_get_drvdata(dev);
 	int ret;
 
-	ret = clk_enable(bdev->bamclk);
+	ret = clk_enable(bdev->clk);
 	if (ret < 0) {
 		dev_err(dev, "clk_enable failed: %d\n", ret);
 		return ret;
@@ -1428,7 +1415,7 @@ static int __maybe_unused bam_dma_suspend(struct device *dev)
 	if (!bdev->controlled_remotely)
 		pm_runtime_force_suspend(dev);
 
-	clk_unprepare(bdev->bamclk);
+	clk_unprepare(bdev->clk);
 
 	return 0;
 }
@@ -1438,7 +1425,7 @@ static int __maybe_unused bam_dma_resume(struct device *dev)
 	struct bam_device *bdev = dev_get_drvdata(dev);
 	int ret;
 
-	ret = clk_prepare(bdev->bamclk);
+	ret = clk_prepare(bdev->clk);
 	if (ret)
 		return ret;
 
-- 
2.17.1