mtd: orion_nand: fix error code path in probe

[Linux-MTD Mailing List]

Gitweb:     http://git.infradead.org/?p=mtd-2.6.git;a=commit;h=a0fa0b66ac1ce73ff791df977b07410a6f4cd337
Commit:     a0fa0b66ac1ce73ff791df977b07410a6f4cd337
Parent:     59af5c7acde3d5cbbf8fadbc81a352a892cbc34c
Author:     Michael Opdenacker <michael.opdenacker at free-electrons.com>
AuthorDate: Thu Oct 16 06:58:35 2014 +0200
Committer:  Brian Norris <computersforpeace at gmail.com>
CommitDate: Wed Oct 22 01:35:41 2014 -0700

    mtd: orion_nand: fix error code path in probe
    
    This replaces kzalloc() and ioremap() calls by devm_ functions
    in the probe() routine, which automatically release the corresponding
    resources when probe() fails or when the device is removed.
    
    This simplifies simplifies the error management code, and brings
    the below improvements or changes:
    
    A. Fixing a bug reported by "make coccicheck":
    
    If "board = devm_kzalloc()" fails, the probe() function jumps
    incorrectly to label "no_res" and therefore returns without
    running iounmap().
    
    B. Requesting the memory region
    
    Using devm_ioremap_resource() makes the probe() function request
    the corresponding memory region before running ioremap(), as
    it is supposed to do.
    
    C. Standardizing the error codes:
    
    The use of devm_ioremap_resource() changes the return value:
     * -ENOMEM instead of -EIO in case of ioremap() failure,
     * -EINVAL instead of -ENODEV in case of platform_get_resource()
       failure.
    
    Signed-off-by: Michael Opdenacker <michael.opdenacker at free-electrons.com>
    Reviewed-by: Jingoo Han <jg1.han at samsung.com>
    Acked-by: Andrew Lunn <andrew at lunn.ch>
    Signed-off-by: Brian Norris <computersforpeace at gmail.com>
---
 drivers/mtd/nand/orion_nand.c | 39 +++++++++++----------------------------
 1 file changed, 11 insertions(+), 28 deletions(-)

diff --git a/drivers/mtd/nand/orion_nand.c b/drivers/mtd/nand/orion_nand.c
index 471b4df..0b49d5d 100644
--- a/drivers/mtd/nand/orion_nand.c
+++ b/drivers/mtd/nand/orion_nand.c
@@ -19,7 +19,7 @@
 #include <linux/mtd/partitions.h>
 #include <linux/clk.h>
 #include <linux/err.h>
-#include <asm/io.h>
+#include <linux/io.h>
 #include <asm/sizes.h>
 #include <linux/platform_data/mtd-orion_nand.h>
 
@@ -85,33 +85,24 @@ static int __init orion_nand_probe(struct platform_device *pdev)
 	int ret = 0;
 	u32 val = 0;
 
-	nc = kzalloc(sizeof(struct nand_chip) + sizeof(struct mtd_info), GFP_KERNEL);
-	if (!nc) {
-		ret = -ENOMEM;
-		goto no_res;
-	}
+	nc = devm_kzalloc(&pdev->dev,
+			sizeof(struct nand_chip) + sizeof(struct mtd_info),
+			GFP_KERNEL);
+	if (!nc)
+		return -ENOMEM;
 	mtd = (struct mtd_info *)(nc + 1);
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!res) {
-		ret = -ENODEV;
-		goto no_res;
-	}
+	io_base = devm_ioremap_resource(&pdev->dev, res);
 
-	io_base = ioremap(res->start, resource_size(res));
-	if (!io_base) {
-		dev_err(&pdev->dev, "ioremap failed\n");
-		ret = -EIO;
-		goto no_res;
-	}
+	if (IS_ERR(io_base))
+		return PTR_ERR(io_base);
 
 	if (pdev->dev.of_node) {
 		board = devm_kzalloc(&pdev->dev, sizeof(struct orion_nand_data),
 					GFP_KERNEL);
-		if (!board) {
-			ret = -ENOMEM;
-			goto no_res;
-		}
+		if (!board)
+			return -ENOMEM;
 		if (!of_property_read_u32(pdev->dev.of_node, "cle", &val))
 			board->cle = (u8)val;
 		else
@@ -185,9 +176,6 @@ no_dev:
 		clk_disable_unprepare(clk);
 		clk_put(clk);
 	}
-	iounmap(io_base);
-no_res:
-	kfree(nc);
 
 	return ret;
 }
@@ -195,15 +183,10 @@ no_res:
 static int orion_nand_remove(struct platform_device *pdev)
 {
 	struct mtd_info *mtd = platform_get_drvdata(pdev);
-	struct nand_chip *nc = mtd->priv;
 	struct clk *clk;
 
 	nand_release(mtd);
 
-	iounmap(nc->IO_ADDR_W);
-
-	kfree(nc);
-
 	clk = clk_get(&pdev->dev, NULL);
 	if (!IS_ERR(clk)) {
 		clk_disable_unprepare(clk);