linux-kernel - [PATCH v5] ata: pata_of_platform: Use platform_get_irq

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Wed,  5 Jan 2022 18:17:21 +0000
From:   Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>
To:     Damien Le Moal <damien.lemoal@...nsource.wdc.com>
Cc:     Rob Herring <robh+dt@...nel.org>,
        Andy Shevchenko <andy.shevchenko@...il.com>,
        Prabhakar <prabhakar.csengg@...il.com>,
        Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>,
        linux-ide@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH v5] ata: pata_of_platform: Use platform_get_irq_optional() to get the interrupt

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_optional().

Note the code does not set the IRQ flags as this is handled automatically
for DT.

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

This patch is part of series [1]. I'll re-visit merging of pata_of_platform
into pata_platform at later point. As my primary focus is removal of static
setup of IRQ resource from DT core code.

[1] https://patchwork.ozlabs.org/project/linux-ide/list/?series=278349

v4->v5
* Set end member of IRQ resource
* Clear irq_res un-conditionally.

Cheers,
Prabhakar
---
 drivers/ata/pata_of_platform.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/ata/pata_of_platform.c b/drivers/ata/pata_of_platform.c
index 35aa158fc976..c3a40b717dcd 100644
--- a/drivers/ata/pata_of_platform.c
+++ b/drivers/ata/pata_of_platform.c
@@ -25,11 +25,12 @@ static int pata_of_platform_probe(struct platform_device *ofdev)
 	struct device_node *dn = ofdev->dev.of_node;
 	struct resource io_res;
 	struct resource ctl_res;
-	struct resource *irq_res;
+	struct resource irq_res;
 	unsigned int reg_shift = 0;
 	int pio_mode = 0;
 	int pio_mask;
 	bool use16bit;
+	int irq;
 
 	ret = of_address_to_resource(dn, 0, &io_res);
 	if (ret) {
@@ -45,7 +46,15 @@ static int pata_of_platform_probe(struct platform_device *ofdev)
 		return -EINVAL;
 	}
 
-	irq_res = platform_get_resource(ofdev, IORESOURCE_IRQ, 0);
+	memset(&irq_res, 0, sizeof(irq_res));
+
+	irq = platform_get_irq_optional(ofdev, 0);
+	if (irq < 0 && irq != -ENXIO)
+		return irq;
+	if (irq > 0) {
+		irq_res.start = irq;
+		irq_res.end = irq;
+	}
 
 	of_property_read_u32(dn, "reg-shift", &reg_shift);
 
@@ -63,7 +72,7 @@ static int pata_of_platform_probe(struct platform_device *ofdev)
 	pio_mask = 1 << pio_mode;
 	pio_mask |= (1 << pio_mode) - 1;
 
-	return __pata_platform_probe(&ofdev->dev, &io_res, &ctl_res, irq_res,
+	return __pata_platform_probe(&ofdev->dev, &io_res, &ctl_res, irq > 0 ? &irq_res : NULL,
 				     reg_shift, pio_mask, &pata_platform_sht,
 				     use16bit);
 }
-- 
2.17.1