Re: [PATCH] ARM: exynos_defconfig: Make S3C2410_WATCHDOG as loadable module

From: Krzysztof Kozlowski
Date: Fri Sep 04 2015 - 02:43:01 EST


On 03.09.2015 14:20, Anand Moon wrote:
> Hi Krzysztof
>
> On 3 September 2015 at 10:32, Krzysztof Kozlowski
> <k.kozlowski@xxxxxxxxxxx> wrote:
>> On 03.09.2015 13:10, Anand Moon wrote:
>>> S3C2410_WATCHDOG watchdog drivers should not be loaded automatically,
>>> but only if a watchdog daemon is installed.
>>
>> First of all: why?
>>
>> Secondly: even as a module driver could be loaded automatically to match
>> enabled device (it has MODULE_DEVICE_TABLE). In the same time loading it
>> does not hurt - watchdog should be inactive:
>>
>> s3c2410-wdt 10060000.watchdog: watchdog inactive, reset disabled, irq
>> disabled
>>
>> Best regards,
>> Krzysztof
>>
>>>
>>> Signed-off-by: Anand Moon <linux.amoon@xxxxxxxxx>
>>> ---
>>> arch/arm/configs/exynos_defconfig | 2 +-
>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/arch/arm/configs/exynos_defconfig b/arch/arm/configs/exynos_defconfig
>>> index aaf7aa4..b5d382e 100644
>>> --- a/arch/arm/configs/exynos_defconfig
>>> +++ b/arch/arm/configs/exynos_defconfig
>>> @@ -101,7 +101,7 @@ CONFIG_CPU_THERMAL=y
>>> CONFIG_THERMAL_EMULATION=y
>>> CONFIG_EXYNOS_THERMAL=y
>>> CONFIG_WATCHDOG=y
>>> -CONFIG_S3C2410_WATCHDOG=y
>>> +CONFIG_S3C2410_WATCHDOG=m
>>> CONFIG_MFD_CROS_EC=y
>>> CONFIG_MFD_CROS_EC_I2C=y
>>> CONFIG_MFD_CROS_EC_SPI=y
>>>
>
> All the watchdog drivers are blacklisted not to be loaded by the ubuntu.
> Their are some configurable parameters which get configured while
> loading of the module using watchdog daemon.
> Watchdog service will reconfigure watchdog driver while loading.

Thank you for clarification. First of all such information (that Ubuntu
requires it) should be put in commit message.

This looks like a requirement specific for Ubuntu. For example on Arch
these modules are not blacklisted. I don't know how this is handled on
Debian or Fedora.

Other defconfigs (including multi_v7) make these modules built-in.

Summarizing I am not convinced that the change is necessary. Having
everything built-in makes testing exynos defconfig easier because some
you just upload zImage and DTB to the testing board. With modules you
have to prepare the initramfs/initrd (e.g. for network boot).

Best regards,
Krzysztof

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/