Commit 675b11d9 authored by Simon Baatz's avatar Simon Baatz Committed by Boris Brezillon
Browse files

mtd: nand: orion: fix clk handling 



The clk handling in orion_nand.c had two problems:

- In the probe function, clk_put() was called for an enabled clock,
  which violates the API (see documentation for clk_put() in
  include/linux/clk.h)

- In the error path of the probe function, clk_put() could be called
  twice for the same clock.

In order to clean this up, use the managed function devm_clk_get() and
store the pointer to the clk in the driver data.

Fixes: baffab28 ('ARM: Orion: fix driver probe error handling with respect to clk')
Cc: <stable@vger.kernel.org> # v4.5+
Signed-off-by: default avatarSimon Baatz <gmbnomis@gmail.com>
Signed-off-by: default avatarBoris Brezillon <boris.brezillon@free-electrons.com>
parent e713ddd8

drivers/mtd/nand/orion_nand.c

+21 −21
Original line number Diff line number Diff line
@@ -23,6 +23,11 @@ 
#include <asm/sizes.h>

#include <linux/platform_data/mtd-orion_nand.h>



struct orion_nand_info {

	struct nand_chip chip;

	struct clk *clk;

};



static void orion_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)

{

	struct nand_chip *nc = mtd_to_nand(mtd);
@@ -75,20 +80,21 @@ static void orion_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len) 


static int __init orion_nand_probe(struct platform_device *pdev)

{

	struct orion_nand_info *info;

	struct mtd_info *mtd;

	struct nand_chip *nc;

	struct orion_nand_data *board;

	struct resource *res;

	struct clk *clk;

	void __iomem *io_base;

	int ret = 0;

	u32 val = 0;



	nc = devm_kzalloc(&pdev->dev,

			sizeof(struct nand_chip),

	info = devm_kzalloc(&pdev->dev,

			sizeof(struct orion_nand_info),

			GFP_KERNEL);

	if (!nc)

	if (!info)

		return -ENOMEM;

	nc = &info->chip;

	mtd = nand_to_mtd(nc);



	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -145,15 +151,13 @@ static int __init orion_nand_probe(struct platform_device *pdev) 
	if (board->dev_ready)

		nc->dev_ready = board->dev_ready;



	platform_set_drvdata(pdev, mtd);

	platform_set_drvdata(pdev, info);



	/* Not all platforms can gate the clock, so it is not

	   an error if the clock does not exists. */

	clk = clk_get(&pdev->dev, NULL);

	if (!IS_ERR(clk)) {

		clk_prepare_enable(clk);

		clk_put(clk);

	}

	info->clk = devm_clk_get(&pdev->dev, NULL);

	if (!IS_ERR(info->clk))

		clk_prepare_enable(info->clk);



	ret = nand_scan(mtd, 1);

	if (ret)
@@ -169,26 +173,22 @@ static int __init orion_nand_probe(struct platform_device *pdev) 
	return 0;



no_dev:

	if (!IS_ERR(clk)) {

		clk_disable_unprepare(clk);

		clk_put(clk);

	}

	if (!IS_ERR(info->clk))

		clk_disable_unprepare(info->clk);



	return ret;

}



static int orion_nand_remove(struct platform_device *pdev)

{

	struct mtd_info *mtd = platform_get_drvdata(pdev);

	struct clk *clk;

	struct orion_nand_info *info = platform_get_drvdata(pdev);

	struct nand_chip *chip = &info->chip;

	struct mtd_info *mtd = nand_to_mtd(chip);



	nand_release(mtd);



	clk = clk_get(&pdev->dev, NULL);

	if (!IS_ERR(clk)) {

		clk_disable_unprepare(clk);

		clk_put(clk);

	}

	if (!IS_ERR(info->clk))

		clk_disable_unprepare(info->clk);



	return 0;

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE