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

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Date:   Sat, 15 Oct 2016 18:42:52 +0200
From:   SF Markus Elfring <elfring@...rs.sourceforge.net>
To:     Sean Young <sean@...s.org>
Cc:     linux-media@...r.kernel.org,
        David Härdeman <david@...deman.nu>,
        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

>> +	/* 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?

Regards,
Markus