[PATCH 5/9] probe/dma/mtk-hs: removed redundant code from mediatek hs dma controller's probe function

[Satendra Singh Thakur]

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

2. Fixed a memory leak when devm_request_irq fails,
Called of_dma_controller_free in such case.

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.tha...@hcl.com>
Signed-off-by: Satendra Singh Thakur <sst2...@gmail.com>
---
 drivers/dma/mediatek/mtk-hsdma.c | 38 ++++++++++----------------------
 1 file changed, 12 insertions(+), 26 deletions(-)

diff --git a/drivers/dma/mediatek/mtk-hsdma.c b/drivers/dma/mediatek/mtk-hsdma.c
index 1a2028e1c29e..6fc01093aeea 100644
--- a/drivers/dma/mediatek/mtk-hsdma.c
+++ b/drivers/dma/mediatek/mtk-hsdma.c
@@ -23,6 +23,7 @@
 #include <linux/pm_runtime.h>
 #include <linux/refcount.h>
 #include <linux/slab.h>
+#include <linux/probe-helper.h>
 
 #include "../virt-dma.h"
 
@@ -896,41 +897,24 @@ static int mtk_hsdma_probe(struct platform_device *pdev)
        struct mtk_hsdma_device *hsdma;
        struct mtk_hsdma_vchan *vc;
        struct dma_device *dd;
-       struct resource *res;
        int i, err;
 
-       hsdma = devm_kzalloc(&pdev->dev, sizeof(*hsdma), GFP_KERNEL);
-       if (!hsdma)
-               return -ENOMEM;
-
+       /*
+        * This macro internally combines following functions:
+        * devm_kzalloc, platform_get_resource, devm_ioremap_resource,
+        * devm_clk_get, platform_get_irq
+        */
+       err = devm_platform_probe_helper(pdev, hsdma, "hsdma");
+       if (err < 0)
+               return err;
        dd = &hsdma->ddev;
 
-       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-       hsdma->base = devm_ioremap_resource(&pdev->dev, res);
-       if (IS_ERR(hsdma->base))
-               return PTR_ERR(hsdma->base);
-
        hsdma->soc = of_device_get_match_data(&pdev->dev);
        if (!hsdma->soc) {
                dev_err(&pdev->dev, "No device match found\n");
                return -ENODEV;
        }
 
-       hsdma->clk = devm_clk_get(&pdev->dev, "hsdma");
-       if (IS_ERR(hsdma->clk)) {
-               dev_err(&pdev->dev, "No clock for %s\n",
-                       dev_name(&pdev->dev));
-               return PTR_ERR(hsdma->clk);
-       }
-
-       res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
-       if (!res) {
-               dev_err(&pdev->dev, "No irq resource for %s\n",
-                       dev_name(&pdev->dev));
-               return -EINVAL;
-       }
-       hsdma->irq = res->start;
-
        refcount_set(&hsdma->pc_refcnt, 0);
        spin_lock_init(&hsdma->lock);
 
@@ -997,7 +981,7 @@ static int mtk_hsdma_probe(struct platform_device *pdev)
        if (err) {
                dev_err(&pdev->dev,
                        "request_irq failed with err %d\n", err);
-               goto err_unregister;
+               goto err_free;
        }
 
        platform_set_drvdata(pdev, hsdma);
@@ -1006,6 +990,8 @@ static int mtk_hsdma_probe(struct platform_device *pdev)
 
        return 0;
 
+err_free:
+       of_dma_controller_free(pdev->dev.of_node);
 err_unregister:
        dma_async_device_unregister(dd);
 
-- 
2.17.1