Re: [PATCH -next] mtd: docg3: Fix passing zero to 'PTR_ERR' warning in doc_probe_device

From: YueHaibing
Date: Wed Jan 23 2019 - 04:44:09 EST



On 2019/1/23 17:12, Boris Brezillon wrote:
> On Wed, 23 Jan 2019 14:58:27 +0800
> YueHaibing <yuehaibing@xxxxxxxxxx> wrote:
>
>> Fix a static code checker warning:
>> drivers/mtd/devices/docg3.c:1875
>> doc_probe_device() warn: passing zero to 'ERR_PTR'
>>
>> Fixes: ae9d4934b2d7 ("mtd: docg3: add multiple floor support")
>> Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx>
>> ---
>> drivers/mtd/devices/docg3.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/mtd/devices/docg3.c b/drivers/mtd/devices/docg3.c
>> index 4c94fc0..60ddc38 100644
>> --- a/drivers/mtd/devices/docg3.c
>> +++ b/drivers/mtd/devices/docg3.c
>> @@ -1872,7 +1872,7 @@ doc_probe_device(struct docg3_cascade *cascade, int floor, struct device *dev)
>> nomem2:
>> kfree(docg3);
>> nomem1:
>> - return ERR_PTR(ret);
>> + return ret ? ERR_PTR(ret) : NULL;
>> }
>>
>
> This is not the right fix, you should instead set ret to -EINVAL:

Thanks , will fix it in v2.

And seems doc_probe_device cannot return NULL. The NULL check of doc_probe_device
in docg3_probe also can been removed, right?

>
> --->8---
> diff --git a/drivers/mtd/devices/docg3.c b/drivers/mtd/devices/docg3.c
> index 4c94fc096696..6b84db411232 100644
> --- a/drivers/mtd/devices/docg3.c
> +++ b/drivers/mtd/devices/docg3.c
> @@ -1842,7 +1842,7 @@ doc_probe_device(struct docg3_cascade *cascade, int floor, struct device *dev)
> chip_id = doc_register_readw(docg3, DOC_CHIPID);
> chip_id_inv = doc_register_readw(docg3, DOC_CHIPID_INV);
>
> - ret = 0;
> + ret = -ENOMEM;
> if (chip_id != (u16)(~chip_id_inv)) {
> goto nomem4;
> }
>
> .
>