[PATCH 0/3] mmc: mmci: Improve system PM support

[PATCH 0/3] mmc: mmci: Improve system PM support

[Ulf Hansson]

This patchset enables mmci to put the device into low power state at system
suspend. Previously the device was always left in full power state.

Do note, these patches were sent during the previous kernel release cycle, as
a part of another patchset on the PM core. Back then, they provided proof of
concept, for the new runtime PM helper functions:
pm_runtime_force_suspend|resume().


Ulf Hansson (3):
  mmc: mmci: Mask IRQs for all variants during runtime suspend
  mmc: mmci: Let runtime PM callbacks be available for CONFIG_PM
  mmc: mmci: Put the device into low power state at system suspend

 drivers/mmc/host/mmci.c |   60 ++++++++++++-----------------------------------
 1 file changed, 15 insertions(+), 45 deletions(-)

-- 
1.7.9.5

[PATCH 1/3] mmc: mmci: Mask IRQs for all variants during runtime suspend

[Ulf Hansson]

In runtime suspended state, we are not expecting IRQs and thus we can
safely mask them, not only for pwrreg_nopower variants but for all.

Obviously we then also need to make sure we restore the IRQ mask while
becoming runtime resumed.

Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
---
 drivers/mmc/host/mmci.c |   23 +++++++++++------------
 1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 771c60a..0f10e3c 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -1794,35 +1794,34 @@ static void mmci_save(struct mmci_host *host)
 {
 	unsigned long flags;
 
-	if (host->variant->pwrreg_nopower) {
-		spin_lock_irqsave(&host->lock, flags);
+	spin_lock_irqsave(&host->lock, flags);
 
-		writel(0, host->base + MMCIMASK0);
+	writel(0, host->base + MMCIMASK0);
+	if (host->variant->pwrreg_nopower) {
 		writel(0, host->base + MMCIDATACTRL);
 		writel(0, host->base + MMCIPOWER);
 		writel(0, host->base + MMCICLOCK);
-		mmci_reg_delay(host);
-
-		spin_unlock_irqrestore(&host->lock, flags);
 	}
+	mmci_reg_delay(host);
 
+	spin_unlock_irqrestore(&host->lock, flags);
 }
 
 static void mmci_restore(struct mmci_host *host)
 {
 	unsigned long flags;
 
-	if (host->variant->pwrreg_nopower) {
-		spin_lock_irqsave(&host->lock, flags);
+	spin_lock_irqsave(&host->lock, flags);
 
+	if (host->variant->pwrreg_nopower) {
 		writel(host->clk_reg, host->base + MMCICLOCK);
 		writel(host->datactrl_reg, host->base + MMCIDATACTRL);
 		writel(host->pwr_reg, host->base + MMCIPOWER);
-		writel(MCI_IRQENABLE, host->base + MMCIMASK0);
-		mmci_reg_delay(host);
-
-		spin_unlock_irqrestore(&host->lock, flags);
 	}
+	writel(MCI_IRQENABLE, host->base + MMCIMASK0);
+	mmci_reg_delay(host);
+
+	spin_unlock_irqrestore(&host->lock, flags);
 }
 
 static int mmci_runtime_suspend(struct device *dev)
-- 
1.7.9.5

[PATCH 2/3] mmc: mmci: Let runtime PM callbacks be available for CONFIG_PM

[Ulf Hansson]

Convert to the SET_PM_RUNTIME_PM macro while defining the runtime PM
callbacks. This means the callbacks becomes available for both
CONFIG_PM_SLEEP and CONFIG_PM_RUNTIME, which is needed to handle the
combinations of these scenarios.

Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
---
 drivers/mmc/host/mmci.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 0f10e3c..eb23c89 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -1789,7 +1789,7 @@ static int mmci_resume(struct device *dev)
 }
 #endif
 
-#ifdef CONFIG_PM_RUNTIME
+#ifdef CONFIG_PM
 static void mmci_save(struct mmci_host *host)
 {
 	unsigned long flags;
@@ -1857,7 +1857,7 @@ static int mmci_runtime_resume(struct device *dev)
 
 static const struct dev_pm_ops mmci_dev_pm_ops = {
 	SET_SYSTEM_SLEEP_PM_OPS(mmci_suspend, mmci_resume)
-	SET_RUNTIME_PM_OPS(mmci_runtime_suspend, mmci_runtime_resume, NULL)
+	SET_PM_RUNTIME_PM_OPS(mmci_runtime_suspend, mmci_runtime_resume, NULL)
 };
 
 static struct amba_id mmci_ids[] = {
-- 
1.7.9.5

[PATCH 3/3] mmc: mmci: Put the device into low power state at system suspend

[Ulf Hansson]

For CONFIG_PM_SLEEP, the device were always left in full power state
after system suspend.

We solely relied on a power domain to put it into low power state,
which is an unreasonable requirement to put on SOCs to implement.
Especially for those SOCs not supporting power domains at all.

Use pm_runtime_force_suspend|resume() as the system suspend callbacks,
to resolve the issue.

Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
---
 drivers/mmc/host/mmci.c |   33 ++-------------------------------
 1 file changed, 2 insertions(+), 31 deletions(-)

diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index eb23c89..a40bf70 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -1759,36 +1759,6 @@ static int mmci_remove(struct amba_device *dev)
 	return 0;
 }
 
-#ifdef CONFIG_SUSPEND
-static int mmci_suspend(struct device *dev)
-{
-	struct amba_device *adev = to_amba_device(dev);
-	struct mmc_host *mmc = amba_get_drvdata(adev);
-
-	if (mmc) {
-		struct mmci_host *host = mmc_priv(mmc);
-		pm_runtime_get_sync(dev);
-		writel(0, host->base + MMCIMASK0);
-	}
-
-	return 0;
-}
-
-static int mmci_resume(struct device *dev)
-{
-	struct amba_device *adev = to_amba_device(dev);
-	struct mmc_host *mmc = amba_get_drvdata(adev);
-
-	if (mmc) {
-		struct mmci_host *host = mmc_priv(mmc);
-		writel(MCI_IRQENABLE, host->base + MMCIMASK0);
-		pm_runtime_put(dev);
-	}
-
-	return 0;
-}
-#endif
-
 #ifdef CONFIG_PM
 static void mmci_save(struct mmci_host *host)
 {
@@ -1856,7 +1826,8 @@ static int mmci_runtime_resume(struct device *dev)
 #endif
 
 static const struct dev_pm_ops mmci_dev_pm_ops = {
-	SET_SYSTEM_SLEEP_PM_OPS(mmci_suspend, mmci_resume)
+	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				pm_runtime_force_resume)
 	SET_PM_RUNTIME_PM_OPS(mmci_runtime_suspend, mmci_runtime_resume, NULL)
 };
 
-- 
1.7.9.5