Subject: Re: [PATCH v3] powerpc: Add i8042 keyboard and mouse irq parsing

From: Benjamin Herrenschmidt <[email-masked]>
Date: Sat, 29 May 2010 13:35:26 +1000

O
> diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
> index 48f0a00..3d169bb 100644
> --- a/arch/powerpc/kernel/setup-common.c
> +++ b/arch/powerpc/kernel/setup-common.c
> @@ -94,6 +94,10 @@ struct screen_info screen_info = {
>  	.orig_video_points = 16
>  };
>  
> +/* Variables required to store legacy IO irq routing */
> +int of_i8042_kbd_irq;
> +int of_i8042_aux_irq;

Is there a reasonable ifdef to use for the above or we don't care ?

>  #ifdef __DO_IRQ_CANON
>  /* XXX should go elsewhere eventually */
>  int ppc_do_canonicalize_irqs;
> @@ -567,6 +571,15 @@ int check_legacy_ioport(unsigned long base_port)
>  			np = of_find_compatible_node(NULL, NULL, "pnpPNP,f03");
>  		if (np) {
>  			parent = of_get_parent(np);
> +
> +			of_i8042_kbd_irq = irq_of_parse_and_map(parent, 0);
> +			if (!of_i8042_kbd_irq)
> +				of_i8042_kbd_irq = 1;
> +
> +			of_i8042_aux_irq = irq_of_parse_and_map(parent, 1);
> +			if (!of_i8042_aux_irq)
> +				of_i8042_aux_irq = 12;
> +
>  			of_node_put(np);
>  			np = parent;
>  			break;
> diff --git a/drivers/input/serio/i8042-io.h b/drivers/input/serio/i8042-io.h
> index 847f4aa..5d48bb6 100644
> --- a/drivers/input/serio/i8042-io.h
> +++ b/drivers/input/serio/i8042-io.h
> @@ -27,6 +27,11 @@
>  #include <asm/irq.h>
>  #elif defined(CONFIG_SH_CAYMAN)
>  #include <asm/irq.h>
> +#elif defined(CONFIG_PPC)
> +extern int of_i8042_kbd_irq;
> +extern int of_i8042_aux_irq;
> +# define I8042_KBD_IRQ  of_i8042_kbd_irq
> +# define I8042_AUX_IRQ  of_i8042_aux_irq
>  #else
>  # define I8042_KBD_IRQ	1
>  # define I8042_AUX_IRQ	12

Now while that works, I do tend to dislike global variables like that.

_Maybe_ a better approach would be to have those #define resolve to
functions:

#define I8042_KBD_IRQ	of_find_i8042_kbd_irq()

Or something like that ?

That means ending up having 2 functions which more/less reproduce the
loop to find the driver in the device-tree but that's a minor
inconvenience.

Now, maybe the variables are less bloat here. What do you think ? Which
way do you prefer ?

Cheers,
Ben.