From:   Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
To:     linux-kernel@vger.kernel.org, Will Deacon <will@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>
Cc:     Rob Herring <robh+dt@kernel.org>,
        Prabhakar <prabhakar.csengg@gmail.com>,
        Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>,
        linux-arm-kernel@lists.infradead.org
Subject: [PATCH] perf/arm-ccn: Use platform_get_irq() to get the interrupt
Date:   Fri, 24 Dec 2021 16:13:31 +0000
Message-Id: <20211224161334.31123-1-prabhakar.mahadev-lad.rj@bp.renesas.com>
Precedence: bulk

platform_get_resource(pdev, IORESOURCE_IRQ, ..) relies on static
allocation of IRQ resources in DT core code, this causes an issue
when using hierarchical interrupt domains using "interrupts" property
in the node as this bypasses the hierarchical setup and messes up the
irq chaining.

In preparation for removal of static setup of IRQ resource from DT core
code use platform_get_irq().

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
Hi,

Dropping usage of platform_get_resource() was agreed based on
the discussion [0].

[0] https://patchwork.kernel.org/project/linux-renesas-soc/
patch/20211209001056.29774-1-prabhakar.mahadev-lad.rj@bp.renesas.com/

Cheers,
Prabhakar
---
 drivers/perf/arm-ccn.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/perf/arm-ccn.c b/drivers/perf/arm-ccn.c
index a96c31604545..40b352e8aa7f 100644
--- a/drivers/perf/arm-ccn.c
+++ b/drivers/perf/arm-ccn.c
@@ -1460,8 +1460,7 @@ static irqreturn_t arm_ccn_irq_handler(int irq, void *dev_id)
 static int arm_ccn_probe(struct platform_device *pdev)
 {
 	struct arm_ccn *ccn;
-	struct resource *res;
-	unsigned int irq;
+	int irq;
 	int err;
 
 	ccn = devm_kzalloc(&pdev->dev, sizeof(*ccn), GFP_KERNEL);
@@ -1474,10 +1473,9 @@ static int arm_ccn_probe(struct platform_device *pdev)
 	if (IS_ERR(ccn->base))
 		return PTR_ERR(ccn->base);
 
-	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
-	if (!res)
-		return -EINVAL;
-	irq = res->start;
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
 
 	/* Check if we can use the interrupt */
 	writel(CCN_MN_ERRINT_STATUS__PMU_EVENTS__DISABLE,
-- 
2.17.1