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dmaengine: rcar-dmac: Make DMAC reinit during system resume explicit

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The current (empty) system sleep callbacks rely on the PM core to force
a runtime resume to reinitialize the DMAC registers during system
resume.  Without a reinitialization, e.g. SCIF DMA will hang silently
after a system resume on R-Car Gen3.

Make this explicit by using pm_runtime_force_{suspend,resume}() as the
system sleep callbacks instead.  Use SET_LATE_SYSTEM_SLEEP_PM_OPS() as
DMA engines must be initialized before all DMA slave devices.

Fixes: 17218e0092 "PM / genpd: Stop/start devices without pm_runtime_force_suspend/resume()"
Suggested-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Geert Uytterhoeven 2018-01-17 10:38:28 +01:00 committed by Rafael J. Wysocki
parent 617fcb6730
commit 1131b0a4af
1 changed files with 7 additions and 17 deletions
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24
drivers/dma/sh/rcar-dmac.c
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@ -1615,22 +1615,6 @@ static struct dma_chan *rcar_dmac_of_xlate(struct of_phandle_args *dma_spec,
* Power management
*/
#ifdef CONFIG_PM_SLEEP
static int rcar_dmac_sleep_suspend(struct device *dev)
{
/*
* TODO: Wait for the current transfer to complete and stop the device.
*/
return 0;
}
static int rcar_dmac_sleep_resume(struct device *dev)
{
/* TODO: Resume transfers, if any. */
return 0;
}
#endif
#ifdef CONFIG_PM
static int rcar_dmac_runtime_suspend(struct device *dev)
{
@ -1646,7 +1630,13 @@ static int rcar_dmac_runtime_resume(struct device *dev)
#endif
static const struct dev_pm_ops rcar_dmac_pm = {
SET_SYSTEM_SLEEP_PM_OPS(rcar_dmac_sleep_suspend, rcar_dmac_sleep_resume)
/*
* TODO for system sleep/resume:
* - 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_RUNTIME_PM_OPS(rcar_dmac_runtime_suspend, rcar_dmac_runtime_resume,
NULL)
};