Commit 01a965d7 authored by Christophe Leroy's avatar Christophe Leroy Committed by Damien Le Moal
Browse files

ata: sata_dwc_460ex: Check !irq instead of irq == NO_IRQ 

NO_IRQ is a relic from the old days. It is not used anymore in core
functions. By the way, function irq_of_parse_and_map() returns value 0
on error.

In some drivers, NO_IRQ is erroneously used to check the return of
irq_of_parse_and_map().

It is not a real bug today because the only architectures using the
drivers being fixed by this patch define NO_IRQ as 0, but there are
architectures which define NO_IRQ as -1. If one day those
architectures start using the non fixed drivers, there will be a
problem.

Long time ago Linus advocated for not using NO_IRQ, see
https://lkml.org/lkml/2005/11/21/221 . He re-iterated the same view
recently in https://lkml.org/lkml/2022/10/12/622



So test !irq instead of tesing irq == NO_IRQ.

And remove the fallback definition of NO_IRQ at the top of the file.

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarDamien Le Moal <damien.lemoal@opensource.wdc.com>
parent aebf1e26

drivers/ata/sata_dwc_460ex.c

+2 −6
Original line number Diff line number Diff line
@@ -42,10 +42,6 @@ 
#define sata_dwc_writel(a, v)	writel_relaxed(v, a)

#define sata_dwc_readl(a)	readl_relaxed(a)



#ifndef NO_IRQ

#define NO_IRQ		0

#endif



#define AHB_DMA_BRST_DFLT	64	/* 16 data items burst length */



enum {
@@ -242,7 +238,7 @@ static int sata_dwc_dma_init_old(struct platform_device *pdev, 


	/* Get SATA DMA interrupt number */

	hsdev->dma->irq = irq_of_parse_and_map(np, 1);

	if (hsdev->dma->irq == NO_IRQ) {

	if (!hsdev->dma->irq) {

		dev_err(dev, "no SATA DMA irq\n");

		return -ENODEV;

	}
@@ -1178,7 +1174,7 @@ static int sata_dwc_probe(struct platform_device *ofdev) 


	/* Get SATA interrupt number */

	irq = irq_of_parse_and_map(np, 0);

	if (irq == NO_IRQ) {

	if (!irq) {

		dev_err(dev, "no SATA DMA irq\n");

		return -ENODEV;

	}