[PATCH] dmaengine: rcar-dmac: Fix too early/late system suspend/resume callbacks

[PATCH] dmaengine: rcar-dmac: Fix too early/late system suspend/resume callbacks

[Geert Uytterhoeven]

If serial console wake-up is enabled ("echo enabled >
/sys/.../ttySC0/power/wakeup"), and any serial input is received while
the system is suspended, serial port input no longer works after system
resume.

Note that:
  1) The system can still be woken up using the serial console,
  2) Serial port input keeps working if the system is woken up in some
     other way (e.g. Wake-on-LAN or gpio-keys), and no serial input was
     received while suspended.

To fix this, replace SET_LATE_SYSTEM_SLEEP_PM_OPS() by
SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(), as the callbacks installed by the
former happen too early resp. late in the suspend resp. resume process.

Reported-by: RVC test team via Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Fixes: 1131b0a4af911de5 ("dmaengine: rcar-dmac: Make DMAC reinit during system resume explicit")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
This is a fix for a regression introduced in v4.16-rc1.
---
 drivers/dma/sh/rcar-dmac.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/sh/rcar-dmac.c b/drivers/dma/sh/rcar-dmac.c
index b10bf71ef5ae2b34..386894fa9ecaa2f1 100644
--- a/drivers/dma/sh/rcar-dmac.c
+++ b/drivers/dma/sh/rcar-dmac.c
@@ -1686,8 +1686,8 @@ static const struct dev_pm_ops rcar_dmac_pm = {
 	 *   - Wait for the current transfer to complete and stop the device,
 	 *   - Resume transfers, if any.
 	 */
-	SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
-				     pm_runtime_force_resume)
+	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				      pm_runtime_force_resume)
 	SET_RUNTIME_PM_OPS(rcar_dmac_runtime_suspend, rcar_dmac_runtime_resume,
 			   NULL)
 };
-- 
2.7.4

Re: [PATCH] dmaengine: rcar-dmac: Fix too early/late system suspend/resume callbacks

[Vinod Koul]

On Thu, Mar 29, 2018 at 06:53:32PM +0200, Geert Uytterhoeven wrote:
> If serial console wake-up is enabled ("echo enabled >
> /sys/.../ttySC0/power/wakeup"), and any serial input is received while
> the system is suspended, serial port input no longer works after system
> resume.
> 
> Note that:
>   1) The system can still be woken up using the serial console,
>   2) Serial port input keeps working if the system is woken up in some
>      other way (e.g. Wake-on-LAN or gpio-keys), and no serial input was
>      received while suspended.
> 
> To fix this, replace SET_LATE_SYSTEM_SLEEP_PM_OPS() by
> SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(), as the callbacks installed by the
> former happen too early resp. late in the suspend resp. resume process.

Applied, thanks

-- 
~Vinod