[PATCH v3] OMAP2+: PM/serial: fix console semaphore acquire during suspend

[Kevin Hilman]

Vitaly Wool <vitalywool at gmail.com> writes:

> On Wed, Dec 8, 2010 at 11:40 PM, Kevin Hilman
> <khilman at deeprootsystems.com> wrote:
>> @@ -120,8 +133,9 @@ static void omap2_enter_full_retention(void)
>>                goto no_sleep;
>>
>>        /* Block console output in case it is on one of the OMAP UARTs */
>> -       if (try_acquire_console_sem())
>> -               goto no_sleep;
>> +       if (!is_suspending())
>> +               if (try_acquire_console_sem())
>> +                       goto no_sleep;
>
> Combine into one if?

personal preference I guess.  I prefer it nested.

>
> <snip>
>
>>        omap_uart_prepare_idle(0);
>>        omap_uart_prepare_idle(1);
>> @@ -136,7 +150,8 @@ static void omap2_enter_full_retention(void)
>>        omap_uart_resume_idle(1);
>>        omap_uart_resume_idle(0);
>>
>> -       release_console_sem();
>> +       if (!is_suspending())
>> +               release_console_sem();
>>
>>  no_sleep:
>>        if (omap2_pm_debug) {
>> @@ -284,6 +299,12 @@ out:
>>        local_irq_enable();
>>  }
>>
>> +static int omap2_pm_begin(suspend_state_t state)
>> +{
>> +       suspend_state = state;
>> +       return 0;
>> +}
>
> Do you really need a return code here?

yes, this function prototype is defined by the driver model, not by me.

>>  static int omap2_pm_prepare(void)
>>  {
>>        /* We cannot sleep in idle until we have resumed */
>> @@ -333,10 +354,18 @@ static void omap2_pm_finish(void)
>>        enable_hlt();
>>  }
>>
>> +static void omap2_pm_end(void)
>> +{
>> +       suspend_state = PM_SUSPEND_ON;
>> +       return;
>> +}
>
> Redundant return.

but harmless

>> +
>>  static struct platform_suspend_ops omap_pm_ops = {
>> +       .begin          = omap2_pm_begin,
>>        .prepare        = omap2_pm_prepare,
>>        .enter          = omap2_pm_enter,
>>        .finish         = omap2_pm_finish,
>> +       .end            = omap2_pm_end,
>>        .valid          = suspend_valid_only_mem,
>>  };
>>
>> diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
>> index 0ec8a04..648b8c5 100644
>> --- a/arch/arm/mach-omap2/pm34xx.c
>> +++ b/arch/arm/mach-omap2/pm34xx.c
>> @@ -50,6 +50,19 @@
>>  #include "sdrc.h"
>>  #include "control.h"
>>
>> +#ifdef CONFIG_SUSPEND
>> +static suspend_state_t suspend_state = PM_SUSPEND_ON;
>> +static inline bool is_suspending(void)
>> +{
>> +       return (suspend_state != PM_SUSPEND_ON);
>> +}
>> +#else
>> +static inline bool is_suspending(void)
>> +{
>> +       return false;
>> +}
>> +#endif
>> +
>>  /* Scratchpad offsets */
>>  #define OMAP343X_TABLE_ADDRESS_OFFSET     0xc4
>>  #define OMAP343X_TABLE_VALUE_OFFSET       0xc0
>> @@ -387,10 +400,11 @@ void omap_sram_idle(void)
>>        }
>>
>>        /* Block console output in case it is on one of the OMAP UARTs */
>> -       if (per_next_state < PWRDM_POWER_ON ||
>> -           core_next_state < PWRDM_POWER_ON)
>> -               if (try_acquire_console_sem())
>> -                       goto console_still_active;
>> +       if (!is_suspending())
>> +               if (per_next_state < PWRDM_POWER_ON ||
>> +                   core_next_state < PWRDM_POWER_ON)
>> +                       if (try_acquire_console_sem())
>> +                               goto console_still_active;
>
> Oh well, 3 nested ifs...

again, personal preference.

Kevin