On Fri, Jul 26, 2013 at 5:56 AM, Grant Likely [off-list ref] wrote:

On Thu, Jul 25, 2013 at 3:58 PM, Geert Uytterhoeven
[off-list ref] wrote:

quoted

On Wed, Jan 11, 2012 at 9:22 PM, Grant Likely [off-list ref] wrote:

quoted

NO_IRQ is evil.  Stop using it in arch/powerpc and powerpc device drivers

quoted

diff --git a/sound/soc/fsl/fsl_ssi.c b/sound/soc/fsl/fsl_ssi.c
index 3e06696..55c6ff9 100644
--- a/sound/soc/fsl/fsl_ssi.c
+++ b/sound/soc/fsl/fsl_ssi.c

@@ -666,7 +666,7 @@ static int __devinit fsl_ssi_probe(struct platform_device *pdev)
        ssi_private->ssi_phys = res.start;

        ssi_private->irq = irq_of_parse_and_map(np, 0);
-       if (ssi_private->irq == NO_IRQ) {
+       if (!ssi_private->irq) {
                dev_err(&pdev->dev, "no irq for node %s\n", np->full_name);
                ret = -ENXIO;
                goto error_iomap;

What's the plan with this patch?

This is now failing on xtensa, as it's one of the architectures that doesn't
define NO_IRQ. Only arm, c6x, mn10300, openrisc, parisc, powerpc, and sparc
define it.

Wow. I'd pretty much dropped that patch because I didn't have time to
chase it down. It should be pursued though.

In that particular case it is safe I think to apply the change. PPC
defines NO_IRQ to be 0 anyway.

Note that we still have arches that define it as nonzero:

arch/arm/include/asm/irq.h:#define NO_IRQ ((unsigned int)(-1))
arch/mn10300/include/asm/irq.h:#define NO_IRQ INT_MAX
arch/openrisc/include/asm/irq.h:#define NO_IRQ (-1)
arch/parisc/include/asm/irq.h:#define NO_IRQ (-1)
arch/sparc/include/asm/irq_32.h:#define NO_IRQ 0xffffffff
arch/sparc/include/asm/irq_64.h:#define NO_IRQ 0xffffffff

Only c6x and powerpc use zero, and thus are ready to drop NO_IRQ.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds