On Sat, Jun 25, 2011 at 5:59 AM, Kevin Hilman [off-list ref] wrote:

"Govindraj.R" [off-list ref] writes:

quoted

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);
}

quoted

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

quoted

Signed-off-by: Govindraj.R <redacted>
---
?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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