Re: [PATCH] drivers: Let several drivers depends on HAS_IOMEM for 'devm_ioremap_resource'

From: Chen Gang
Date: Tue Jul 15 2014 - 10:38:47 EST

On 07/15/2014 09:11 AM, Chen Gang wrote:
> On 07/15/2014 08:53 AM, Guenter Roeck wrote:
>> On 07/14/2014 05:34 PM, Chen Gang wrote:
>>> On 07/14/2014 05:22 PM, Chen Gang wrote:
>>>> å 2014å7æ14æïäå4:57ïRichard Weinberger <richard@xxxxxx> åéï
>>>>> Am 14.07.2014 10:48, schrieb Lars-Peter Clausen:
>>>>>> On 07/14/2014 10:31 AM, Richard Weinberger wrote:
>>>>>>> Am 13.07.2014 22:17, schrieb Greg Kroah-Hartman:
>>>>>>>> On Sun, Jul 13, 2014 at 09:33:38PM +0200, Richard Weinberger wrote:
>>>>>>>>> Maybe we could add COMPILE_TEST to the version string too?
>>>>>>>>> Just to detect such kernels fast in user bug reports...
>>>>>>>> What kind of bug report are you going to get?
>>>>>>> User manages to enable CONFIG_FOO by selecting COMPILE_TEST and
>>>>>>> complains that it does not work. :)
>>>>>> These drivers are typically drivers for some SoC peripheral and the
>>>>>> device will simply physically not exist on a platform that does not
>>>>>> provide HAS_IOMEM. This is not really any
>>>>>> different from making the driver selectable via COMPILE_TEST for
>>>>>> any other platform. To hit the issue you'd have to instantiate a
>>>>>> device driver instance for a device that
>>>>>> physically does not exist. This will always result in a failure.
>>>>> Okay, you have convinced me. :)
>>> After search the history patches, I found one related patch which made
>>> by myself (when I am in Asianux):
>>> "";
>>> For me, it is a long discussion, and forced many members have to join
>>> in. Please help check again.
>> One thing you could try would be to return NULL (or where appropriate
>> an error) in the #else case of CONFIG_HAS_IOMEM and CONFIG_HAS_IOPORT,
>> ie dont take COMPILE_TEST into account at all. Obviously that means
>> you won't be able to dump a warning message in the COMPILE_TEST
>> case, but at least the code would compile. The rejection of above patch
>> would make a good case for this approach.
> OK, thanks: at least, it can be improved. But still welcome any other
> opinions of another related members.

If no reply within 3 days (2014-07-18), I shall try to send related
patch for it within this week end (2014-07-20).

Chen Gang

Open share and attitude like air water and life which God blessed
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