[PATCH v3 11/12] OMAP2: Serial: Add has_async_wake flag.
Govindraj
govindraj.ti at gmail.com
Mon Jun 27 09:09:54 EDT 2011
On Sat, Jun 25, 2011 at 5:59 AM, Kevin Hilman <khilman at ti.com> wrote:
> "Govindraj.R" <govindraj.raja at ti.com> writes:
>
>> Prior to this patch the uart_clock was cut using prepare/resume calls since
>> these funcs are no more available with runtime changes use has_async_wake
>> flag to keep clock active during bootup otherwise uart port will disabled
>> during boot-up and cannot be enabled back.
>
> Is this only a bootup issue, or a runtime PM issue? It appears to me
> that with this patch, runtime PM is effectively disabled for the whole
> time.
>
it boots up fine, its a runtime PM issue where there is
no mechanism to wakeup after clock cutting from
runtime autosuspend.
> Why not just use pm_runtime_disable() in _probe() for devices with no
> async wakeup.
>
Agree.
can drop of this patch and bind below changes in runtime conversion patch 04/12
do pm_runtime_enable only if device_may_wakeup
is true in probe.
<<SNIP>>
in serial_omap_probe
if (device_may_wakeup(&pdev->dev)) {
pm_runtime_use_autosuspend(&pdev->dev);
pm_runtime_set_autosuspend_delay(&pdev->dev,
OMAP_UART_AUTOSUSPEND_DELAY);
pm_runtime_enable(&pdev->dev);
pm_runtime_irq_safe(&pdev->dev);
}
>> Also based on this flag we can disable uart port during suspend and
>> enable back during resume for omap_socs that have not set
>> has_async_wake.
>
> Then you can use pm_runtime_enable() in ->prepare() and
> pm_runtime_disable() in ->complete()
>
u mean runtime enable in suspend and runtime disable in resume
if device_may_wakeup is false.
<<SNIP>>
in serial_omap_suspend
if (!device_may_wakeup(&pdev->dev))
pm_runtime_enable(&pdev->dev);
--
Thanks,
Govindraj.R
> Kevin
>
>> Signed-off-by: Govindraj.R <govindraj.raja at ti.com>
>> ---
>> arch/arm/mach-omap2/serial.c | 1 +
>> arch/arm/plat-omap/include/plat/omap-serial.h | 3 +++
>> drivers/tty/serial/omap-serial.c | 14 ++++++++++++++
>> 3 files changed, 18 insertions(+), 0 deletions(-)
>>
>> diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c
>> index 4bc5914..0a95c95 100644
>> --- a/arch/arm/mach-omap2/serial.c
>> +++ b/arch/arm/mach-omap2/serial.c
>> @@ -266,6 +266,7 @@ static void omap_uart_idle_init(struct omap_uart_port_info *uart,
>> break;
>> }
>> uart->wk_mask = wk_mask;
>> + uart->has_async_wake = true;
>> } else if (cpu_is_omap24xx()) {
>> u32 wk_mask = 0;
>> u32 wk_en = PM_WKEN1, wk_st = PM_WKST1;
>> diff --git a/arch/arm/plat-omap/include/plat/omap-serial.h b/arch/arm/plat-omap/include/plat/omap-serial.h
>> index b5117bd..69e6d4b 100644
>> --- a/arch/arm/plat-omap/include/plat/omap-serial.h
>> +++ b/arch/arm/plat-omap/include/plat/omap-serial.h
>> @@ -79,6 +79,7 @@ struct omap_uart_port_info {
>> void __iomem *wk_st;
>> void __iomem *wk_en;
>> u32 wk_mask;
>> + bool has_async_wake;
>> };
>>
>> struct uart_omap_dma {
>> @@ -134,6 +135,8 @@ struct uart_omap_port {
>> unsigned int errata;
>> void (*enable_wakeup)(struct platform_device *, bool);
>> bool (*chk_wakeup)(struct platform_device *);
>> +
>> + bool has_async_wake;
>> };
>>
>> #endif /* __OMAP_SERIAL_H__ */
>> diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
>> index c3561dd..dbe76f3 100644
>> --- a/drivers/tty/serial/omap-serial.c
>> +++ b/drivers/tty/serial/omap-serial.c
>> @@ -1181,6 +1181,13 @@ static int serial_omap_suspend(struct device *dev)
>> uart_suspend_port(&serial_omap_reg, &up->port);
>> console_trylock();
>> serial_omap_pm(&up->port, 3, 0);
>> +
>> + /* OMAP2 dont have async wakeup from prcm.
>> + * For such socs clocks will be kept active from probe and
>> + * cut only in suspend path.
>> + */
>> + if (!up->has_async_wake)
>> + serial_omap_port_disable(up);
>> }
>> return 0;
>> }
>> @@ -1192,6 +1199,9 @@ static int serial_omap_resume(struct device *dev)
>> if (up) {
>> uart_resume_port(&serial_omap_reg, &up->port);
>> console_unlock();
>> +
>> + if (!up->has_async_wake)
>> + serial_omap_port_enable(up);
>> }
>>
>> return 0;
>> @@ -1415,6 +1425,7 @@ static int serial_omap_probe(struct platform_device *pdev)
>> up->errata = omap_up_info->errata;
>> up->enable_wakeup = omap_up_info->enable_wakeup;
>> up->chk_wakeup = omap_up_info->chk_wakeup;
>> + up->has_async_wake = omap_up_info->has_async_wake;
>>
>> if (omap_up_info->dma_enabled) {
>> up->uart_dma.uart_dma_tx = dma_tx->start;
>> @@ -1443,6 +1454,9 @@ static int serial_omap_probe(struct platform_device *pdev)
>> serial_omap_port_disable(up);
>> }
>>
>> + if (!up->has_async_wake)
>> + serial_omap_port_enable(up);
>> +
>> ui[pdev->id] = up;
>> serial_omap_add_console_port(up);
> --
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