Re: [PATCH 12/17] irqchip: Add support for LAN966x OIC

From: Herve Codina <herve.codina@bootlin.com>
To: Simon Horman <horms@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>,
	Rob Herring <robh@kernel.org>,
	Krzysztof Kozlowski <krzk+dt@kernel.org>,
	Conor Dooley <conor+dt@kernel.org>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	Lee Jones <lee@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
	Horatiu Vultur <horatiu.vultur@microchip.com>,
	UNGLinuxDriver@microchip.com, Andrew Lunn <andrew@lunn.ch>,
	Heiner Kallweit <hkallweit1@gmail.com>,
	Russell King <linux@armlinux.org.uk>,
	Saravana Kannan <saravanak@google.com>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Philipp Zabel <p.zabel@pengutronix.de>,
	Lars Povlsen <lars.povlsen@microchip.com>,
	Steen Hegelund <Steen.Hegelund@microchip.com>,
	Daniel Machon <daniel.machon@microchip.com>,
	Alexandre Belloni <alexandre.belloni@bootlin.com>,
	linux-kernel@vger.kernel.org, devicetree@vger.kernel.org,
	netdev@vger.kernel.org, linux-pci@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	Allan Nielsen <allan.nielsen@microchip.com>,
	Luca Ceresoli <luca.ceresoli@bootlin.com>,
	Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Subject: Re: [PATCH 12/17] irqchip: Add support for LAN966x OIC
Date: Thu, 2 May 2024 15:24:09 +0200	[thread overview]
Message-ID: <20240502152409.70a85339@bootlin.com> (raw)
In-Reply-To: <20240430202451.GF2575892@kernel.org>

Hi Simon,

On Tue, 30 Apr 2024 21:24:51 +0100
Simon Horman <horms@kernel.org> wrote:

> On Tue, Apr 30, 2024 at 10:37:21AM +0200, Herve Codina wrote:
> > The Microchip LAN966x outband interrupt controller (OIC) maps the
> > internal interrupt sources of the LAN966x device to an external
> > interrupt.
> > When the LAN966x device is used as a PCI device, the external interrupt
> > is routed to the PCI interrupt.
> > 
> > Signed-off-by: Herve Codina <herve.codina@bootlin.com>  
> 
> Hi Herve,
> 
> > +static int lan966x_oic_probe(struct platform_device *pdev)
> > +{
> > +	struct device_node *node = pdev->dev.of_node;
> > +	struct lan966x_oic_data *lan966x_oic;
> > +	struct device *dev = &pdev->dev;
> > +	struct irq_chip_generic *gc;
> > +	int ret;
> > +	int i;
> > +
> > +	lan966x_oic = devm_kmalloc(dev, sizeof(*lan966x_oic), GFP_KERNEL);
> > +	if (!lan966x_oic)
> > +		return -ENOMEM;
> > +
> > +	lan966x_oic->regs = devm_platform_ioremap_resource(pdev, 0);
> > +	if (IS_ERR(lan966x_oic->regs))
> > +		return dev_err_probe(dev, PTR_ERR(lan966x_oic->regs),
> > +				     "failed to map resource\n");
> > +
> > +	lan966x_oic->domain = irq_domain_alloc_linear(of_node_to_fwnode(node),
> > +						      LAN966X_OIC_NR_IRQ,
> > +						      &irq_generic_chip_ops, NULL);  
> 
> nit: Please consider limiting lines to 80 columns wide in Networking code.

This will be done in the next iteration.

> 
> > +	if (!lan966x_oic->domain) {
> > +		dev_err(dev, "failed to create an IRQ domain\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	lan966x_oic->irq = platform_get_irq(pdev, 0);
> > +	if (lan966x_oic->irq < 0) {
> > +		dev_err_probe(dev, lan966x_oic->irq, "failed to get the IRQ\n");
> > +		goto err_domain_free;  
> 
> Hi,
> 
> This will result in the function returning ret.
> However, ret is uninitialised here.
> 
> Flagged by W=1 builds with clang-18, and Smatch.

Indeed, this fill be fixed in the next iteration.

Best regards,
Hervé

-- 
Hervé Codina, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com