[PATCH 3/6] gpio/omap: remove suspend_wakeup field from struct gpio_bank
DebBarma, Tarun Kanti
tarun.kanti at ti.com
Tue Feb 28 04:39:05 EST 2012
On Tue, Feb 28, 2012 at 5:24 AM, Kevin Hilman <khilman at ti.com> wrote:
> Tarun Kanti DebBarma <tarun.kanti at ti.com> writes:
>
>> Since we already have bank->context.wake_en to keep track
>> of gpios which are wakeup enabled, there is no need to have
>> this field any more.
>>
>> Signed-off-by: Tarun Kanti DebBarma <tarun.kanti at ti.com>
>
> I'm not crazy about this change...
>
>> ---
>> drivers/gpio/gpio-omap.c | 11 +++++------
>> 1 files changed, 5 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
>> index 64f15d5..b62e861 100644
>> --- a/drivers/gpio/gpio-omap.c
>> +++ b/drivers/gpio/gpio-omap.c
>> @@ -53,7 +53,6 @@ struct gpio_bank {
>> void __iomem *base;
>> u16 irq;
>> u16 virtual_irq_start;
>> - u32 suspend_wakeup;
>> u32 non_wakeup_gpios;
>> u32 enabled_non_wakeup_gpios;
>> struct gpio_regs context;
>> @@ -497,9 +496,9 @@ static int _set_gpio_wakeup(struct gpio_bank *bank, int gpio, int enable)
>>
>> spin_lock_irqsave(&bank->lock, flags);
>> if (enable)
>> - bank->suspend_wakeup |= gpio_bit;
>> + bank->context.wake_en |= gpio_bit;
>> else
>> - bank->suspend_wakeup &= ~gpio_bit;
>> + bank->context.wake_en &= ~gpio_bit;
>
> The bank->context values are expected to be copies of the actual
> register contents, and here that is clearly not the case.
Right, it should have been this:
if (enable)
- bank->suspend_wakeup |= gpio_bit;
+ bank->context.wake_en |= gpio_bit;
else
- bank->suspend_wakeup &= ~gpio_bit;
+ bank->context.wake_en &= ~gpio_bit;
+
+ __raw_writel(bank->context.wake_en, bank->base + bank->regs->wkup_en);
>
> With this change, you're using the context register to track changes
> that you *might* eventually write to the register.
The above change ensures that bank->context.wake_en reflects the
latest register value.
There are two distinct paths through which bank->context.wake_en is
updated now, viz:
Path1:-
chip.irq_set_type() --> gpio_irq_type() --> _set_gpio_triggering() -->
set_gpio_trigger()
Path2:-
chip.irq_set_wake() --> gpio_wake_enable() --> irq_set_wake()
>
> IMO, this is more confusing than having a separate field to track this.
So, there is no need have a separate field to keep track of this.
I hope my understanding is right.
--
Tarun
>
> Kevin
>
>> spin_unlock_irqrestore(&bank->lock, flags);
>>
>> @@ -772,7 +771,7 @@ static int omap_mpuio_suspend_noirq(struct device *dev)
>>
>> spin_lock_irqsave(&bank->lock, flags);
>> bank->context.wake_en = __raw_readl(mask_reg);
>> - __raw_writel(0xffff & ~bank->suspend_wakeup, mask_reg);
>> + __raw_writel(0xffff & ~bank->context.wake_en, mask_reg);
>> spin_unlock_irqrestore(&bank->lock, flags);
>>
>> return 0;
>> @@ -1137,12 +1136,12 @@ static int omap_gpio_suspend(struct device *dev)
>> if (!bank->mod_usage || !bank->loses_context)
>> return 0;
>>
>> - if (!bank->regs->wkup_en || !bank->suspend_wakeup)
>> + if (!bank->regs->wkup_en || !bank->context.wake_en)
>> return 0;
>>
>> spin_lock_irqsave(&bank->lock, flags);
>> _gpio_rmw(base, bank->regs->wkup_en, 0xffffffff, 0);
>> - _gpio_rmw(base, bank->regs->wkup_en, bank->suspend_wakeup, 1);
>> + _gpio_rmw(base, bank->regs->wkup_en, bank->context.wake_en, 1);
>> spin_unlock_irqrestore(&bank->lock, flags);
>>
>> return 0;
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