From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marc Zyngier <marc.zyngier@arm.com>
Subject: Re: [PATCH v7 11/14] irqchip: ti-sci-inta: Add support for Interrupt
 Aggregator driver
Date: Mon, 29 Apr 2019 09:47:55 +0100
Message-ID: <79b34c45-023b-2df4-26f4-e151e74a46ac@arm.com>
References: <20190420100950.7997-1-lokeshvutla@ti.com>
 <20190420100950.7997-12-lokeshvutla@ti.com>
 <bb768bc0-e18b-3794-8083-1612da10b0c1@ti.com>
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To: Lokesh Vutla <lokeshvutla@ti.com>, Santosh Shilimkar <ssantosh@kernel.org>, Rob Herring <robh+dt@kernel.org>, Nishanth Menon <nm@ti.com>, tglx@linutronix.de, jason@lakedaemon.net
Cc: Linux ARM Mailing List <linux-arm-kernel@lists.infradead.org>, linux-kernel@vger.kernel.org, Tero Kristo <t-kristo@ti.com>, Sekhar Nori <nsekhar@ti.com>, Tony Lindgren <tony@atomide.com>, linus.walleij@linaro.org, Peter Ujfalusi <peter.ujfalusi@ti.com>, Grygorii Strashko <grygorii.strashko@ti.com>, Device Tree Mailing List <devicetree@vger.kernel.org>
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On 23/04/2019 11:00, Lokesh Vutla wrote:
> Hi Marc,

[...]

>> +/**
>> + * ti_sci_inta_set_type() - Update the trigger type of the irq.
>> + * @data:	Pointer to corresponding irq_data
>> + * @type:	Trigger type as specified by user
>> + *
>> + * Note: This updates the handle_irq callback for level msi.
>> + *
>> + * Return 0 if all went well else appropriate error.
>> + */
>> +static int ti_sci_inta_set_type(struct irq_data *data, unsigned int type)
>> +{
>> +	struct irq_desc *desc = irq_to_desc(data->irq);
>> +
>> +	/*
>> +	 * .alloc default sets handle_edge_irq. But if the user specifies
>> +	 * that IRQ is level MSI, then update the handle to handle_level_irq
>> +	 */
>> +	if (type & IRQF_TRIGGER_HIGH)
>> +		desc->handle_irq = handle_level_irq;
>> +
>> +	return 0;
> 
> 
> Returning error value is causing request_irq to fail, so still returning 0. Do
> you suggest any other method to handle this?

But that is the very point, isn't it? If you pass the wrong triggering
type to request_irq, it *must* fail. What you should have is something like:

switch (type & IRQ_TYPE_SENSE_MASK) {
case IRQF_TRIGGER_HIGH:
	desc->handle_irq = handle_level_irq;
	return 0;
case IRQ_TYPE_EDGE_RISING:
	return 0;
default:
	return -EINVAL;
}

(adjust as necessary).

What's wrong with this?

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...