| Message ID | 13feefdf6b240817944e6441e26a8ddc1d81ced1.1668102802.git.christophe.leroy@csgroup.eu (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 8836402d4b208b2211fc60538ff45d6bb3b73a64 |
| Headers | show |
| Series | [v2] usb: Check !irq instead of irq == NO_IRQ | expand |
On Thu, Nov 10, 2022 at 06:54:35PM +0100, Christophe Leroy wrote: > 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> > --- > drivers/usb/host/ehci-grlib.c | 2 +- > drivers/usb/host/ehci-ppc-of.c | 2 +- > drivers/usb/host/fhci-hcd.c | 2 +- > drivers/usb/host/ohci-ppc-of.c | 2 +- > drivers/usb/host/uhci-grlib.c | 2 +- > 5 files changed, 5 insertions(+), 5 deletions(-) For the [eou]hci-* files: Acked-by: Alan Stern <stern@rowland.harvard.edu> Alan Stern
diff --git a/drivers/usb/host/ehci-grlib.c b/drivers/usb/host/ehci-grlib.c index a2c3b4ec8a8b..0717f2ccf49d 100644 --- 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 28a19693c19f..62a0a193798c 100644 --- 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 95a44462bed0..64a64140c2fd 100644 --- 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 591f675cc930..f2f6c832ec98 100644 --- 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 3ef6d52839e5..907d5f01edfd 100644 --- 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;
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> --- drivers/usb/host/ehci-grlib.c | 2 +- drivers/usb/host/ehci-ppc-of.c | 2 +- drivers/usb/host/fhci-hcd.c | 2 +- drivers/usb/host/ohci-ppc-of.c | 2 +- drivers/usb/host/uhci-grlib.c | 2 +- 5 files changed, 5 insertions(+), 5 deletions(-)