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Date: Tue, 16 Sep 2014 18:37:32 +0800
From: Yijing Wang <wangyijing@huawei.com>
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To: Lucas Stach <l.stach@pengutronix.de>
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Subject: Re: [PATCH v1 03/21] MSI: Remove the redundant irq_set_chip_data()
References: <1409911806-10519-1-git-send-email-wangyijing@huawei.com>		 <1409911806-10519-4-git-send-email-wangyijing@huawei.com>	 <1410789648.3314.5.camel@pengutronix.de> <541792C0.9090303@huawei.com> <1410863349.2746.5.camel@pengutronix.de>
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>>> arch_teardown_msi_irq() expects to find the msi_chip in the irq
>>> chip_data field. As this means drivers don't have any reasonable other
>>> possibility to stuff things into this field, I think it would make sense
>>> to do the cleanup the other way around: keep the irq_set_chip_data
>>> arch_setup_msi_irq() and rip it out of the individual drivers.
>>
>> Hi Lucas, thanks for your review and comments!
>> irq_set_chip_data() should not be placed in MSI core functions, because other arch like x86,
>> use irq_data->chip_data to stores irq_cfg. So how to set the chip_data is arch dependent.
>> And this series is mainly to use MSI chip framework in all platforms.
>> Currently, only ARM platform MSI drivers use the chip_data to store msi_chip, and the drivers call
>> irq_set_chip_data() in their driver already. So I thought we should clean up it in MSI core code.
>>
> Okay I see your point, so the cleanup done this way is okay.
> 
> But then this still introduces a problem: arch_teardown_msi_irq()
> expects to find the msi_chip in the chip_data field, which is okay for
> all ARM PCI host drivers, but not for other arch MSI chips.
> 
> You fix this by completely removing arch_teardown_msi_irq() at the end
> of the series, but this still has the potential to introduce issues for
> other arches than ARM within the series. So this patch should include a
> change to replace the line
> 
> struct msi_chip *chip = irq_get_chip_data(irq);
> 
> with something that doesn't rely on the msi_chip being in the irq
> chip_data field.

OK, I will update arch_teardown_msi_irq() in this patch, thanks!

Thanks!
Yijing.

> 
> Regards,
> Lucas
> 


-- 
Thanks!
Yijing