[PATCH 2/4] pinctrl: exynos: Add irq_chip instance for Exynos7 wakeup interrupts

[Abhilash Kesavan]

Hi Tomasz,

On Sat, Sep 13, 2014 at 4:57 PM, Tomasz Figa <tomasz.figa at gmail.com> wrote:
> Hi Abhilash,
>
> Please see my comments inline.
>
> On 13.09.2014 10:50, Abhilash Kesavan wrote:
>> Exynos7 uses different offsets for wakeup interrupt configuration registers.
>> So a new irq_chip instance for Exynos7 wakeup interrupts is added. The irq_chip
>> selection is now based on the wakeup interrupt controller compatible string.
>
> [snip]
>
>> @@ -328,9 +322,11 @@ static int exynos_wkup_irq_set_wake(struct irq_data *irqd, unsigned int on)
>>  /*
>>   * irq_chip for wakeup interrupts
>>   */
>> -static struct exynos_irq_chip exynos_wkup_irq_chip = {
>> +static struct exynos_irq_chip exynos_wkup_irq_chip;
>> +
>
> Why do you still need this, if you have both variants below?

After adding __initdata to the two variants, I will require to have a
copy of one of them.

>
>> +static struct exynos_irq_chip exynos4210_wkup_irq_chip = {
>>       .chip = {
>> -             .name = "exynos_wkup_irq_chip",
>> +             .name = "exynos4210_wkup_irq_chip",
>>               .irq_unmask = exynos_irq_unmask,
>>               .irq_mask = exynos_irq_mask,
>>               .irq_ack = exynos_irq_ack,
>> @@ -342,6 +338,29 @@ static struct exynos_irq_chip exynos_wkup_irq_chip = {
>>       .eint_pend = EXYNOS_WKUP_EPEND_OFFSET,
>>  };
>>
>> +static struct exynos_irq_chip exynos7_wkup_irq_chip = {
>> +     .chip = {
>> +             .name = "exynos7_wkup_irq_chip",
>> +             .irq_unmask = exynos_irq_unmask,
>> +             .irq_mask = exynos_irq_mask,
>> +             .irq_ack = exynos_irq_ack,
>> +             .irq_set_type = exynos_irq_set_type,
>> +             .irq_set_wake = exynos_wkup_irq_set_wake,
>> +     },
>> +     .eint_con = EXYNOS7_WKUP_ECON_OFFSET,
>> +     .eint_mask = EXYNOS7_WKUP_EMASK_OFFSET,
>> +     .eint_pend = EXYNOS7_WKUP_EPEND_OFFSET,
>> +};
>> +
>> +/* list of external wakeup controllers supported */
>> +static const struct of_device_id exynos_wkup_irq_ids[] = {
>> +     { .compatible = "samsung,exynos4210-wakeup-eint",
>> +                     .data = &exynos4210_wkup_irq_chip },
>> +     { .compatible = "samsung,exynos7-wakeup-eint",
>> +                     .data = &exynos7_wkup_irq_chip },
>> +     { }
>> +};
>> +
>>  /* interrupt handler for wakeup interrupts 0..15 */
>>  static void exynos_irq_eint0_15(unsigned int irq, struct irq_desc *desc)
>>  {
>> @@ -434,7 +453,12 @@ static int exynos_eint_wkup_init(struct samsung_pinctrl_drv_data *d)
>>       int idx, irq;
>>
>>       for_each_child_of_node(dev->of_node, np) {
>> -             if (of_match_node(exynos_wkup_irq_ids, np)) {
>> +             const struct of_device_id *match;
>> +
>> +             match = of_match_node(exynos_wkup_irq_ids, np);
>> +             if (match) {
>> +                     memcpy(&exynos_wkup_irq_chip, match->data,
>> +                             sizeof(struct exynos_irq_chip));
>
> Hmm, this doesn't look correct to me. You are modifying a static struct
> here. Why couldn't you simply use the exynos irq chip pointed by
> match->data in further registration code?

That will not be available later once I use __initdata.

>
>>                       wkup_np = np;
>>                       break;
>>               }
>> diff --git a/drivers/pinctrl/samsung/pinctrl-exynos.h b/drivers/pinctrl/samsung/pinctrl-exynos.h
>> index e060722..0db1e52 100644
>> --- a/drivers/pinctrl/samsung/pinctrl-exynos.h
>> +++ b/drivers/pinctrl/samsung/pinctrl-exynos.h
>> @@ -25,6 +25,9 @@
>>  #define EXYNOS_WKUP_ECON_OFFSET              0xE00
>>  #define EXYNOS_WKUP_EMASK_OFFSET     0xF00
>>  #define EXYNOS_WKUP_EPEND_OFFSET     0xF40
>> +#define EXYNOS7_WKUP_ECON_OFFSET     0x700
>> +#define EXYNOS7_WKUP_EMASK_OFFSET    0x900
>> +#define EXYNOS7_WKUP_EPEND_OFFSET    0xA00
>
> Interestingly enough, the offsets look just like the normal GPIO
> interrupt controller of previous Exynos SoCs. Are you sure those are
> correct? Also if somehow the controller now resembles the normal one,
> doesn't it have the SVC register making it possible to reuse the non
> wake-up code instead?

The wakeup interrupt register offsets are the same as the GPIO
interrupt offsets in earlier Exynos SoCs. There is no SVC register for
the wakeup interrupt block.

Regards,
Abhilash

>
> Best regards,
> Tomasz