[PATCH 9/9] probe/dma/owl: removed redundant code from owl dma controller's probe function

From: Satendra Singh Thakur <sst2005@gmail.com>
To: unlisted-recipients:; (no To-header on input)
Cc: satendrasingh.thakur@hcl.com,
	"Satendra Singh Thakur" <sst2005@gmail.com>,
	"Andreas Färber" <afaerber@suse.de>,
	"Manivannan Sadhasivam" <manivannan.sadhasivam@linaro.org>,
	"Vinod Koul" <vkoul@kernel.org>,
	"Dan Williams" <dan.j.williams@intel.com>,
	linux-arm-kernel@lists.infradead.org, dmaengine@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH 9/9] probe/dma/owl: removed redundant code from owl dma controller's probe function
Date: Sun, 15 Sep 2019 13:02:36 +0530	[thread overview]
Message-ID: <20190915073237.24176-1-sst2005@gmail.com> (raw)
In-Reply-To: <20190915072644.23329-1-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
are replaced with a macro devm_platform_probe_helper.

2. 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/owl-dma.c | 29 +++++++++--------------------
 1 file changed, 9 insertions(+), 20 deletions(-)

diff --git a/drivers/dma/owl-dma.c b/drivers/dma/owl-dma.c
index 90bbcef99ef8..03e692fc25a1 100644
--- a/drivers/dma/owl-dma.c
+++ b/drivers/dma/owl-dma.c
@@ -23,6 +23,7 @@
 #include <linux/of_device.h>
 #include <linux/of_dma.h>
 #include <linux/slab.h>
+#include <linux/probe-helper.h>
 #include "virt-dma.h"
 
 #define OWL_DMA_FRAME_MAX_LENGTH		0xfffff
@@ -1045,20 +1046,15 @@ static int owl_dma_probe(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
 	struct owl_dma *od;
-	struct resource *res;
 	int ret, i, nr_channels, nr_requests;
-
-	od = devm_kzalloc(&pdev->dev, sizeof(*od), GFP_KERNEL);
-	if (!od)
-		return -ENOMEM;
-
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!res)
-		return -EINVAL;
-
-	od->base = devm_ioremap_resource(&pdev->dev, res);
-	if (IS_ERR(od->base))
-		return PTR_ERR(od->base);
+	/*
+	 * This macro internally combines following functions:
+	 * devm_kzalloc, platform_get_resource, devm_ioremap_resource,
+	 * devm_clk_get, platform_get_irq
+	 */
+	ret = devm_platform_probe_helper(pdev, od, NULL);
+	if (ret < 0)
+		return ret;
 
 	ret = of_property_read_u32(np, "dma-channels", &nr_channels);
 	if (ret) {
@@ -1105,18 +1101,11 @@ static int owl_dma_probe(struct platform_device *pdev)
 
 	INIT_LIST_HEAD(&od->dma.channels);
 
-	od->clk = devm_clk_get(&pdev->dev, NULL);
-	if (IS_ERR(od->clk)) {
-		dev_err(&pdev->dev, "unable to get clock\n");
-		return PTR_ERR(od->clk);
-	}
-
 	/*
 	 * Eventhough the DMA controller is capable of generating 4
 	 * IRQ's for DMA priority feature, we only use 1 IRQ for
 	 * simplification.
 	 */
-	od->irq = platform_get_irq(pdev, 0);
 	ret = devm_request_irq(&pdev->dev, od->irq, owl_dma_interrupt, 0,
 			       dev_name(&pdev->dev), od);
 	if (ret) {
-- 
2.17.1

