Re: [PATCH -queue v0 5/6] [loongson] rtc: enable legacy RTC driver on fuloong2f

From: Arnaud Patard
Date: Wed Nov 04 2009 - 06:34:37 EST

Wu Zhangjin <wuzhangjin@xxxxxxxxx> writes:

> Hi,
> On Wed, 2009-11-04 at 11:40 +0100, Arnaud Patard wrote:
>> Wu Zhangjin <wuzhangjin@xxxxxxxxx> writes:
>> Hi,
>> > RTC_LIB is selected by MIPS by default, and therefore, the legacy RTC driver is
>> > disabled. but unfortunately, RTC_LIB not works on fulong, so, enabling the legcy
>> > RTC driver is needed, otherwise, the tools like hwclock will not work.
>> >
>> > because loongson family machines, including fuloong2e, fuloong2f and
>> > yeeloong2f need to enable legacy RTC driver, so we use MACH_LOONGSON
>> > here.
>> There are loongson machines which are working fine with RTC_LIB (for
>> instance the gdium which is using a m41t83 on i2c) so would be better to
>> be more restrictive imho.
> In reality, fuloong2e, fuloong2f and yeeloong2f work fine with RTC_LIB,
> but relative patches need to append to drivers/rtc/rtc-cmos.c and also
> need a RTC platform device. If what I remembered is right, Gdium also
> need corresponding patches to make it work with RTC_LIB.

As I said, Gdium is using an i2c chip and the bus is made with the sm501
gpio. So except the patch for gpiolib support for ls2f, there's nothing
special for RTC_LIB. It's just working out of the box (as long as you
declare the platform devices but that's not what I call a problem).

> Herein, I just let the basic support for those machines work, and then,
> the RTC_LIB support will be sent out later.
> and a small question: if legacy RTC driver works well on these machines,
> why should we forbid people to use it? I think it's better to remove the
> "select RTC_LIB" line for MIPS, and then, the people will be free to
> choose what they want, and even for the users whose platform not support

Well, I though about this. If you go that way and remove the "select
RTC_LIB", please check and enable it for all platforms which needs it or
warn people about. Would be nice to avoid regression due to that.

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