Commit 8836402d authored Nov 10, 2022 by Christophe Leroy Committed by Greg Kroah-Hartman Nov 11, 2022

usb: 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.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/13feefdf6b240817944e6441e26a8ddc1d81ced1.1668102802.git.christophe.leroy@csgroup.eu


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 46ed6026

drivers/usb/host/ehci-grlib.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -99,7 +99,7 @@ static int ehci_hcd_grlib_probe(struct platform_device *op)
		hcd->rsrc_len = resource_size(&res);

		irq = irq_of_parse_and_map(dn, 0);
		if (irq == NO_IRQ) {
		if (!irq) {
		dev_err(&op->dev, "%s: irq_of_parse_and_map failed\n",
		__FILE__);
		rv = -EBUSY;

drivers/usb/host/ehci-ppc-of.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -119,7 +119,7 @@ static int ehci_hcd_ppc_of_probe(struct platform_device *op)
		hcd->rsrc_len = resource_size(&res);

		irq = irq_of_parse_and_map(dn, 0);
		if (irq == NO_IRQ) {
		if (!irq) {
		dev_err(&op->dev, "%s: irq_of_parse_and_map failed\n",
		__FILE__);
		rv = -EBUSY;

drivers/usb/host/fhci-hcd.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -676,7 +676,7 @@ static int of_fhci_probe(struct platform_device *ofdev)

		/* USB Host interrupt. */
		usb_irq = irq_of_parse_and_map(node, 0);
		if (usb_irq == NO_IRQ) {
		if (!usb_irq) {
		dev_err(dev, "could not get usb irq\n");
		ret = -EINVAL;
		goto err_usb_irq;

drivers/usb/host/ohci-ppc-of.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -120,7 +120,7 @@ static int ohci_hcd_ppc_of_probe(struct platform_device *op)
		}

		irq = irq_of_parse_and_map(dn, 0);
		if (irq == NO_IRQ) {
		if (!irq) {
		dev_err(&op->dev, "%s: irq_of_parse_and_map failed\n",
		__FILE__);
		rv = -EBUSY;

drivers/usb/host/uhci-grlib.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -116,7 +116,7 @@ static int uhci_hcd_grlib_probe(struct platform_device *op)
		hcd->rsrc_len = resource_size(&res);

		irq = irq_of_parse_and_map(dn, 0);
		if (irq == NO_IRQ) {
		if (!irq) {
		printk(KERN_ERR "%s: irq_of_parse_and_map failed\n", __FILE__);
		rv = -EBUSY;
		goto err_usb;