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Subject: Re: [PATCH v1 03/21] MSI: Remove the redundant irq_set_chip_data()
From: Lucas Stach <l.stach@pengutronix.de>
To: Yijing Wang <wangyijing@huawei.com>
Date: Mon, 15 Sep 2014 16:00:48 +0200
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Cc: linux-mips@linux-mips.org, linux-ia64@vger.kernel.org,
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Am Freitag, den 05.09.2014, 18:09 +0800 schrieb Yijing Wang:
> Currently, pcie-designware, pcie-rcar, pci-tegra drivers
> use irq chip_data to save the msi_chip pointer. They
> already call irq_set_chip_data() in their own MSI irq map
> functions. So irq_set_chip_data() in arch_setup_msi_irq()
> is useless.
> 
> Signed-off-by: Yijing Wang <wangyijing@huawei.com>
> ---
>  drivers/pci/msi.c |    2 --
>  1 files changed, 0 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
> index f6cb317..d547f7f 100644
> --- a/drivers/pci/msi.c
> +++ b/drivers/pci/msi.c
> @@ -41,8 +41,6 @@ int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
>  	if (err < 0)
>  		return err;
>  
> -	irq_set_chip_data(desc->irq, chip);
> -
>  	return 0;
>  }
>  

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.

Regards,
Lucas

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