Hi Wen,
Wen Yang <yellowriver2...@hotmail.com> wrote on Thu, 7 Feb 2019
11:56:48 +0000:
> of_find_device_by_node() takes a reference to the struct device
> when it finds a match via get_device, there is no need to call
> get_device() twice.
> We also should make sure to drop the reference to the device
> taken by of_find_device_by_node() on driver unbind.
>
> Fixes: f88fc122cc34 ("mtd: nand: Cleanup/rework the atmel_nand driver")
> Signed-off-by: Wen Yang <yellowriver2...@hotmail.com>
> ---
> v5->v4: Add new line, add people in Cc and remove all Cc lines.
> v4->v3: Avoid two times of calling grtform_get_drvdata()
> v3->v2: Change the commit message.
> v2->v1: Add missing Fixes tag.
>
> drivers/mtd/nand/raw/atmel/pmecc.c | 22 ++++++++++++++++------
> 1 file changed, 16 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/mtd/nand/raw/atmel/pmecc.c
> b/drivers/mtd/nand/raw/atmel/pmecc.c
> index 555a74e..97e47ea 100644
> --- a/drivers/mtd/nand/raw/atmel/pmecc.c
> +++ b/drivers/mtd/nand/raw/atmel/pmecc.c
> @@ -876,23 +876,33 @@ static struct atmel_pmecc
> *atmel_pmecc_get_by_node(struct device *userdev,
> {
> struct platform_device *pdev;
> struct atmel_pmecc *pmecc, **ptr;
> + int ret;
>
> pdev = of_find_device_by_node(np);
> - if (!pdev || !platform_get_drvdata(pdev))
> + if (!pdev)
> return ERR_PTR(-EPROBE_DEFER);
>
> - ptr = devres_alloc(devm_atmel_pmecc_put, sizeof(*ptr), GFP_KERNEL);
> - if (!ptr)
> - return ERR_PTR(-ENOMEM);
> -
> - get_device(&pdev->dev);
> pmecc = platform_get_drvdata(pdev);
> + if (!pmecc) {
> + ret = -EPROBE_DEFER;
> + goto err_put_device;
> + }
> +
> + ptr = devres_alloc(devm_atmel_pmecc_put, sizeof(*ptr), GFP_KERNEL);
> + if (!ptr) {
> + ret = -ENOMEM;
> + goto err_put_device;
> + }
>
> *ptr = pmecc;
>
> devres_add(userdev, ptr);
>
> return pmecc;
> +
> +err_put_device:
> + put_device(&pdev->dev);
> + return ERR_PTR(ret);
> }
>
> static const int atmel_pmecc_strengths[] = { 2, 4, 8, 12, 24, 32 };
Series applied to nand/next.
Thanks,
Miquèl
