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Subject: Re: [PATCH] serial: 8250_fintek: fix the mismatched IRQ mode
To: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
References: <1464314571-15429-1-git-send-email-hpeter+linux_kernel@gmail.com>
 <CAPybu_2BM-Nm02Y6xv-jg0MMaNGuEgmG6=5S3OO3KuwDUPmHMg@mail.gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>, jslaby@suse.com,
        Alan Cox <alan@linux.intel.com>,
        Peter Hurley <peter@hurleysoftware.com>,
        =?UTF-8?B?UEEyMCBUT00gVFNBSSDolKHlrpfkvZE=?= 
	<tom_tsai@fintek.com.tw>,
        Peter H <peter_hong@fintek.com.tw>, linux-serial@vger.kernel.org,
        LKML <linux-kernel@vger.kernel.org>,
        "Ji-Ze Hong (Peter Hong)" <hpeter+linux_kernel@gmail.com>
From: "Ji-Ze Hong (Peter Hong)" <hpeter@gmail.com>
Message-ID: <430c447a-bf8f-6268-9d55-e29ada539ea2@gmail.com>
Date: Tue, 28 Jun 2016 08:51:38 +0800
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Hi Ricardo & Greg,

Ricardo Ribalda Delgado 於 2016/6/27 下午 06:25 寫道:
> Hi Peter,. Hi Greg
> On Fri, May 27, 2016 at 4:02 AM, Ji-Ze Hong (Peter Hong)
>> +       struct irq_data *irq_data = irq_get_irq_data(uart->port.irq);
>> +       bool level_mode = irqd_is_level_type(irq_data);
>
> I see a potential problem with this patch:
>
> If irq_get_irq_data fails, it will return NULL, resulting on a
> segmentation fault on irqd_is_level_type:
>
> #define __irqd_to_state(d) ACCESS_PRIVATE((d)->common, state_use_accessors)
>
>
> I believe that we need to add error checks here

I'll try to send a patch to add more checks.

>> -       return 0;
>> +       return fintek_8250_set_irq_mode(pdata, level_mode);
>
> Also why do not call irq_get_irq_data() and  irqd_is_level_type()
> before return? There is no need to do that work if the probe
> determines that it is not a fintek chip.
>

Also determine the IRQ mode when found a fintek chip.

Thanks to point out the potential issue.
-- 
With Best Regards,
Peter Hung