linux-kernel - Re: [PATCH 4/5] [media] winbond-cir: One variable and its check less in wbcir

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Message-ID: <403be317930e0915cbe98c15cd6adf66@hardeman.nu>
Date:   Wed, 19 Oct 2016 13:10:31 +0000
From:   "David Härdeman" <david@...deman.nu>
To:     "SF Markus Elfring" <elfring@...rs.sourceforge.net>,
        "Sean Young" <sean@...s.org>
Cc:     linux-media@...r.kernel.org,
        "Mauro Carvalho Chehab" <mchehab@...nel.org>,
        "LKML" <linux-kernel@...r.kernel.org>,
        kernel-janitors@...r.kernel.org,
        "Julia Lawall" <julia.lawall@...6.fr>
Subject: Re: [PATCH 4/5] [media] winbond-cir: One variable and its check
 less in wbcir_shutdown() after error detection

October 15, 2016 6:42 PM, "SF Markus Elfring" <elfring@...rs.sourceforge.net> wrote:
>>> + /* Set CEIR_EN */
>>> + wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_CTL, 0x01, 0x01);
>>> +set_irqmask:
>>> /*
>>> * ACPI will set the HW disable bit for SP3 which means that the
>>> * output signals are left in an undefined state which may cause
>>> @@ -876,6 +858,14 @@ wbcir_shutdown(struct pnp_dev *device)
>>> */
>>> wbcir_set_irqmask(data, WBCIR_IRQ_NONE);
>>> disable_irq(data->irq);
>>> + return;
>>> +clear_bits:
>>> + /* Clear BUFF_EN, Clear END_EN, Clear MATCH_EN */
>>> + wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_EV_EN, 0x00, 0x07);
>>> +
>>> + /* Clear CEIR_EN */
>>> + wbcir_set_bits(data->wbase + WBCIR_REG_WCEIR_CTL, 0x00, 0x01);
>>> + goto set_irqmask;
>> 
>> I'm not convinced that adding a goto which goes backwards is making this
>> code any more readible, just so that a local variable can be dropped.
> 
> Thanks for your feedback.
> 
> Is such a "backward jump" usual and finally required when you would like
> to move a bit of common error handling code to the end without using extra
> local variables and a few statements should still be performed after it?
> 

I'm sorry, I can't parse this.