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>

diff --git a/drivers/usb/host/ehci-grlib.c b/drivers/usb/host/ehci-grlib.c
index a2c3b4e..0717f2c 100644 (file)
--- a/drivers/usb/host/ehci-grlib.c
+++ b/drivers/usb/host/ehci-grlib.c
@@ -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;

diff --git a/drivers/usb/host/ehci-ppc-of.c b/drivers/usb/host/ehci-ppc-of.c
index 28a1969..62a0a19 100644 (file)
--- a/drivers/usb/host/ehci-ppc-of.c
+++ b/drivers/usb/host/ehci-ppc-of.c
@@ -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;

diff --git a/drivers/usb/host/fhci-hcd.c b/drivers/usb/host/fhci-hcd.c
index 95a4446..64a6414 100644 (file)
--- a/drivers/usb/host/fhci-hcd.c
+++ b/drivers/usb/host/fhci-hcd.c
@@ -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;

diff --git a/drivers/usb/host/ohci-ppc-of.c b/drivers/usb/host/ohci-ppc-of.c
index 591f675..f2f6c83 100644 (file)
--- a/drivers/usb/host/ohci-ppc-of.c
+++ b/drivers/usb/host/ohci-ppc-of.c
@@ -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;

diff --git a/drivers/usb/host/uhci-grlib.c b/drivers/usb/host/uhci-grlib.c
index 3ef6d52..907d5f0 100644 (file)
--- a/drivers/usb/host/uhci-grlib.c
+++ b/drivers/usb/host/uhci-grlib.c
@@ -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;