[PATCH v2] mmc: davinci: Fix and simplify probe failure path

[Pramod Gurav]

The sequence of resource release in probe failure path in this
driver was wrong and needed fixes to cleanly unload the driver.
This changes does the same by switching to managed resources and
fixes return path to release resource in proper sequence.

Cc: Chris Ball <chris@xxxxxxxxxx>
Cc: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Cc: linux-mmc@xxxxxxxxxxxxxxx
Signed-off-by: Pramod Gurav <pramod.gurav@xxxxxxxxxxxxxxx>
---
Changes since v1:
- Dropped IS_ERR check on devm_ioremap() return.
- Fixed sequence on mmc_remove_host in fail as well as in remove function

 drivers/mmc/host/davinci_mmc.c |   91 +++++++++++++++-------------------------
 1 file changed, 33 insertions(+), 58 deletions(-)

diff --git a/drivers/mmc/host/davinci_mmc.c b/drivers/mmc/host/davinci_mmc.c
index 5d4c5e0..dc49b22 100644
--- a/drivers/mmc/host/davinci_mmc.c
+++ b/drivers/mmc/host/davinci_mmc.c
@@ -1242,22 +1242,20 @@ static int __init davinci_mmcsd_probe(struct platform_device *pdev)
 		return -ENOENT;
 	}
 
-	ret = -ENODEV;
 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	irq = platform_get_irq(pdev, 0);
 	if (!r || irq == NO_IRQ)
-		goto out;
+		return -ENODEV;
 
-	ret = -EBUSY;
 	mem_size = resource_size(r);
-	mem = request_mem_region(r->start, mem_size, pdev->name);
+	mem = devm_request_mem_region(&pdev->dev, r->start, mem_size,
+				      pdev->name);
 	if (!mem)
-		goto out;
+		return -EBUSY;
 
-	ret = -ENOMEM;
 	mmc = mmc_alloc_host(sizeof(struct mmc_davinci_host), &pdev->dev);
 	if (!mmc)
-		goto out;
+		return -ENOMEM;
 
 	host = mmc_priv(mmc);
 	host->mmc = mmc;	/* Important */
@@ -1275,15 +1273,16 @@ static int __init davinci_mmcsd_probe(struct platform_device *pdev)
 		host->txdma = r->start;
 
 	host->mem_res = mem;
-	host->base = ioremap(mem->start, mem_size);
-	if (!host->base)
-		goto out;
+	host->base = devm_ioremap(&pdev->dev, mem->start, mem_size);
+	if (!host->base) {
+		ret = -ENOMEM;
+		goto err_ioremap;
+	}
 
-	ret = -ENXIO;
-	host->clk = clk_get(&pdev->dev, "MMCSDCLK");
+	host->clk = devm_clk_get(&pdev->dev, "MMCSDCLK");
 	if (IS_ERR(host->clk)) {
 		ret = PTR_ERR(host->clk);
-		goto out;
+		goto err_ioremap;
 	}
 	clk_enable(host->clk);
 	host->mmc_input_clk = clk_get_rate(host->clk);
@@ -1350,20 +1349,22 @@ static int __init davinci_mmcsd_probe(struct platform_device *pdev)
 	ret = mmc_davinci_cpufreq_register(host);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to register cpufreq\n");
-		goto cpu_freq_fail;
+		goto err_cpu_freq;
 	}
 
 	ret = mmc_add_host(mmc);
 	if (ret < 0)
-		goto out;
+		goto err_mmc_add;
 
-	ret = request_irq(irq, mmc_davinci_irq, 0, mmc_hostname(mmc), host);
+	ret = devm_request_irq(&pdev->dev, irq, mmc_davinci_irq, 0,
+			       mmc_hostname(mmc), host);
 	if (ret)
-		goto out;
+		goto err_request_irq;
 
 	if (host->sdio_irq >= 0) {
-		ret = request_irq(host->sdio_irq, mmc_davinci_sdio_irq, 0,
-				  mmc_hostname(mmc), host);
+		ret = devm_request_irq(&pdev->dev, host->sdio_irq,
+				       mmc_davinci_sdio_irq, 0,
+				       mmc_hostname(mmc), host);
 		if (!ret)
 			mmc->caps |= MMC_CAP_SDIO_IRQ;
 	}
@@ -1376,27 +1377,15 @@ static int __init davinci_mmcsd_probe(struct platform_device *pdev)
 
 	return 0;
 
-out:
+err_request_irq:
+	mmc_remove_host(mmc);
+err_mmc_add:
 	mmc_davinci_cpufreq_deregister(host);
-cpu_freq_fail:
-	if (host) {
-		davinci_release_dma_channels(host);
-
-		if (host->clk) {
-			clk_disable(host->clk);
-			clk_put(host->clk);
-		}
-
-		if (host->base)
-			iounmap(host->base);
-	}
-
-	if (mmc)
-		mmc_free_host(mmc);
-
-	if (mem)
-		release_resource(mem);
-
+err_cpu_freq:
+	davinci_release_dma_channels(host);
+	clk_disable(host->clk);
+err_ioremap:
+	mmc_free_host(mmc);
 	dev_dbg(&pdev->dev, "probe err %d\n", ret);
 
 	return ret;
@@ -1406,25 +1395,11 @@ static int __exit davinci_mmcsd_remove(struct platform_device *pdev)
 {
 	struct mmc_davinci_host *host = platform_get_drvdata(pdev);
 
-	if (host) {
-		mmc_davinci_cpufreq_deregister(host);
-
-		mmc_remove_host(host->mmc);
-		free_irq(host->mmc_irq, host);
-		if (host->mmc->caps & MMC_CAP_SDIO_IRQ)
-			free_irq(host->sdio_irq, host);
-
-		davinci_release_dma_channels(host);
-
-		clk_disable(host->clk);
-		clk_put(host->clk);
-
-		iounmap(host->base);
-
-		release_resource(host->mem_res);
-
-		mmc_free_host(host->mmc);
-	}
+	mmc_remove_host(host->mmc);
+	mmc_davinci_cpufreq_deregister(host);
+	davinci_release_dma_channels(host);
+	clk_disable(host->clk);
+	mmc_free_host(host->mmc);
 
 	return 0;
 }
-- 
1.7.9.5

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