[PATCH 05/17] mmc: mmci: Put the device into low power state at system suspend

Ulf Hansson [off-list ref] writes:

On 4 February 2014 20:22, Kevin Hilman [off-list ref] wrote:

quoted

Ulf Hansson [off-list ref] writes:

quoted

Due to the available runtime PM callbacks, we are now able to put our
device into low power state at system suspend.

Earlier we could not accomplish this without trusting a power domain
for the device to take care of it. Now we are able to cope with
scenarios both with and without a power domain.

Cc: Russell King <redacted>
Signed-off-by: Ulf Hansson <redacted>
---
 drivers/mmc/host/mmci.c |   45 +++++++++++++++++++++++++--------------------
 1 file changed, 25 insertions(+), 20 deletions(-)

diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index c88da1c..074e0cb 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c

@@ -1723,33 +1723,38 @@ static int mmci_remove(struct amba_device *dev)
      return 0;
 }

-#ifdef CONFIG_SUSPEND
-static int mmci_suspend(struct device *dev)
+#ifdef CONFIG_PM_SLEEP
+static int mmci_suspend_late(struct device *dev)
 {
-     struct amba_device *adev = to_amba_device(dev);
-     struct mmc_host *mmc = amba_get_drvdata(adev);
+     int ret = 0;

-     if (mmc) {
-             struct mmci_host *host = mmc_priv(mmc);
-             pm_runtime_get_sync(dev);
-             writel(0, host->base + MMCIMASK0);
-     }
+     if (pm_runtime_status_suspended(dev))
+             return 0;

-     return 0;
+     if (dev->pm_domain && dev->pm_domain->ops.runtime_suspend)
+             ret = dev->pm_domain->ops.runtime_suspend(dev);
+     else
+             ret = dev->bus->pm->runtime_suspend(dev);
+
+     if (!ret)
+             pm_runtime_set_suspended(dev);

Isn't this basically open-coding pm_runtime_suspend()...

It is similar, but with once big difference.

Since the PM core prevents pm_runtime_suspend() from invoking our
->runtime_suspend callback during system suspend (it does so by
invoking pm_runtime_get_sync() before starting the suspend sequence),
we then need to make the driver handle that by itself.

Yeah, I still think we need to allow a bus/pm_domain to override that
behavior.


Kevin