nagai/kernel
3
0
Fork 0
forked from mirrors/linux
Code Pull requests Activity

platform: finally disallow IRQ0 in platform_get_irq() and its ilk

Browse source 
The commit a85a6c86c2 ("driver core: platform: Clarify that IRQ 0 is
invalid") only calls WARN() when IRQ0 is about to be returned, however
using IRQ0 is considered invalid (according to Linus) outside the arch/
code where it's used by the i8253 drivers. Many driver subsystems treat
0 specially (e.g. as an indication of the polling mode by libata), so
the users of platform_get_irq[_byname]() in them would have to filter
out IRQ0 explicitly and this (quite obviously) doesn't scale...
Let's finally get this straight and return -EINVAL instead of IRQ0!

Fixes: a85a6c86c2 ("driver core: platform: Clarify that IRQ 0 is invalid")
Acked-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Link: https://lore.kernel.org/r/025679e1-1f0a-ae4b-4369-01164f691511@omp.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Sergey Shtylyov 2022-03-11 22:35:29 +03:00 committed by Greg Kroah-Hartman
parent a72b6dff40
commit ce753ad154
1 changed files with 4 additions and 2 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

6
drivers/base/platform.c
View file

@ -231,7 +231,8 @@ int platform_get_irq_optional(struct platform_device *dev, unsigned int num)
out_not_found: out_not_found:
ret = -ENXIO; ret = -ENXIO;
out: out:
WARN(ret == 0, "0 is an invalid IRQ number\n"); if (WARN(!ret, "0 is an invalid IRQ number\n"))
return -EINVAL;
return ret; return ret;
} }
EXPORT_SYMBOL_GPL(platform_get_irq_optional); EXPORT_SYMBOL_GPL(platform_get_irq_optional);
@ -446,7 +447,8 @@ static int __platform_get_irq_byname(struct platform_device *dev,
r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name); r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
if (r) { if (r) {
WARN(r->start == 0, "0 is an invalid IRQ number\n"); if (WARN(!r->start, "0 is an invalid IRQ number\n"))
return -EINVAL;
return r->start; return r->start;
} }