[PATCH v2] powerpc: Add i8042 keyboard and mouse irq parsing

[Grant Likely]

On Mon, May 24, 2010 at 10:25 AM, Martyn Welch <martyn.welch at ge.com> wrote:
> Currently the irqs for the i8042, which historically provides keyboard and
> mouse (aux) support, is hardwired in the driver rather than parsing the
> dts.  This patch modifies the powerpc legacy IO code to attempt to parse
> the device tree for this information, failing back to the hardcoded values
> if it fails.
>
> Signed-off-by: Martyn Welch <martyn.welch at ge.com>
> ---
>
> v2: This patch no longer requires the DTS files to be modified, reading the
> interrupts from the current location as suggested by Grant.
>
>  arch/powerpc/kernel/setup-common.c |   49 ++++++++++++++++++++++++++++++++++--
>  drivers/input/serio/i8042-io.h     |    8 ++++++
>  2 files changed, 54 insertions(+), 3 deletions(-)
>
> diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
> index 48f0a00..7f1bb99 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;
> +
>  #ifdef __DO_IRQ_CANON
>  /* XXX should go elsewhere eventually */
>  int ppc_do_canonicalize_irqs;
> @@ -558,13 +562,52 @@ void probe_machine(void)
>  /* Match a class of boards, not a specific device configuration. */
>  int check_legacy_ioport(unsigned long base_port)
>  {
> -       struct device_node *parent, *np = NULL;
> +       struct device_node *parent, *np = NULL, *np_aux = NULL;
>        int ret = -ENODEV;
>
>        switch(base_port) {
>        case I8042_DATA_REG:
> -               if (!(np = of_find_compatible_node(NULL, NULL, "pnpPNP,303")))
> -                       np = of_find_compatible_node(NULL, NULL, "pnpPNP,f03");
> +               np = of_find_compatible_node(NULL, NULL, "pnpPNP,303");
> +               if (np) {
> +                       /* Interrupt routing in parent node */
> +                       parent = of_get_parent(np);
> +                       if (parent) {
> +                               /*
> +                                * Attempt to parse DTS for keyboard irq,
> +                                * fallback to standard.
> +                                */
> +                               of_i8042_kbd_irq = irq_of_parse_and_map(parent,
> +                                       0);
> +                               if (!of_i8042_kbd_irq)
> +                                       of_i8042_kbd_irq = 1;
> +
> +                               of_node_put(parent);
> +                       }
> +               }
> +
> +               np_aux = of_find_compatible_node(NULL, NULL, "pnpPNP,f03");
> +               if (np_aux) {
> +                       if (!np) {
> +                               of_node_put(np);
> +                               np = np_aux;
> +                       }
> +
> +                       /* Interrupt routing in parent node */
> +                       parent = of_get_parent(np_aux);
> +                       if (parent) {
> +                               /*
> +                                * Attempt to parse DTS for mouse (aux) irq,
> +                                * fallback to standard.
> +                                */
> +                               of_i8042_aux_irq = irq_of_parse_and_map(parent,
> +                                       1);
> +                               if (!of_i8042_aux_irq)
> +                                       of_i8042_aux_irq = 12;
> +
> +                               of_node_put(parent);
> +                       }
> +               }
> +

This seems to be a lot more code that you need.  The existing code
already obtains a pointer to the parent node for you.  All you really
should need to add is the two calls to irq_of_parse_and_map() for
obtaining the kbd and aux irq numbers.

>                if (np) {
>                        parent = of_get_parent(np);
>                        of_node_put(np);
> diff --git a/drivers/input/serio/i8042-io.h b/drivers/input/serio/i8042-io.h
> index 847f4aa..8fc8753 100644
> --- a/drivers/input/serio/i8042-io.h
> +++ b/drivers/input/serio/i8042-io.h
> @@ -19,6 +19,11 @@
>  * IRQs.
>  */
>
> +#if defined(CONFIG_PPC)
> +extern int of_i8042_kbd_irq;
> +extern int of_i8042_aux_irq;
> +#endif

Please fold these two extern definitions into the #elif
defined(CONFIG_PPC) block below.

> +
>  #ifdef __alpha__
>  # define I8042_KBD_IRQ 1
>  # define I8042_AUX_IRQ (RTC_PORT(0) == 0x170 ? 9 : 12) /* Jensen is special */
> @@ -27,6 +32,9 @@
>  #include <asm/irq.h>
>  #elif defined(CONFIG_SH_CAYMAN)
>  #include <asm/irq.h>
> +#elif defined(CONFIG_PPC)
> +#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

Cheers,
g.