On Wed, Apr 18, 2012 at 01:57:27PM +0200, Vitaly Wool wrote:

Hi Ulf,

On Tue, Jan 17, 2012 at 3:34 PM, Ulf Hansson [off-list ref] wrote:

quoted

To disable a levelshifter when we are in an idle state will
decrease current consumption. We make use of the ios_handler
at runtime suspend and at regular suspend to accomplish this.

Of course depending on the used levelshifter the decrease of
current differs. For ST6G3244ME the value is up to ~200 uA.

Tested-by: Linus Walleij <redacted>
Signed-off-by: Ulf Hansson <redacted>
Signed-off-by: Linus Walleij <redacted>
---
?drivers/mmc/host/mmci.c | ? 19 ++++++++++++++++++-
?1 files changed, 18 insertions(+), 1 deletions(-)

diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index a7c8f8f..76ce2cd 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c

@@ -1505,10 +1505,22 @@ static int mmci_save(struct amba_device *dev)

?{
? ? ? ?struct mmc_host *mmc = amba_get_drvdata(dev);
? ? ? ?unsigned long flags;
+ ? ? ? struct mmc_ios ios;
+ ? ? ? int ret = 0;

? ? ? ?if (mmc) {
? ? ? ? ? ? ? ?struct mmci_host *host = mmc_priv(mmc);

+ ? ? ? ? ? ? ? /* Let the ios_handler act on a POWER_OFF to save power. */
+ ? ? ? ? ? ? ? if (host->plat->ios_handler) {
+ ? ? ? ? ? ? ? ? ? ? ? memcpy(&ios, &mmc->ios, sizeof(struct mmc_ios));
+ ? ? ? ? ? ? ? ? ? ? ? ios.power_mode = MMC_POWER_OFF;
+ ? ? ? ? ? ? ? ? ? ? ? ret = host->plat->ios_handler(mmc_dev(mmc),
+ ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? &ios);
+ ? ? ? ? ? ? ? ? ? ? ? if (ret)
+ ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? return ret;
+ ? ? ? ? ? ? ? }
+
? ? ? ? ? ? ? ?spin_lock_irqsave(&host->lock, flags);

? ? ? ? ? ? ? ?/*

@@ -1527,7 +1539,7 @@ static int mmci_save(struct amba_device *dev)

? ? ? ? ? ? ? ?amba_vcore_disable(dev);
? ? ? ?}

- ? ? ? return 0;
+ ? ? ? return ret;
?}

?static int mmci_restore(struct amba_device *dev)

@@ -1550,6 +1562,11 @@ static int mmci_restore(struct amba_device *dev)

? ? ? ? ? ? ? ?writel(MCI_IRQENABLE, host->base + MMCIMASK0);

? ? ? ? ? ? ? ?spin_unlock_irqrestore(&host->lock, flags);
+
+ ? ? ? ? ? ? ? /* Restore settings done by the ios_handler. */
+ ? ? ? ? ? ? ? if (host->plat->ios_handler)
+ ? ? ? ? ? ? ? ? ? ? ? host->plat->ios_handler(mmc_dev(mmc),
+ ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? &mmc->ios);
? ? ? ?}

? ? ? ?return 0;

this patch is a disaster because it cuts off the chip's power on
suspend regardless of whether MMC_PM_KEEP_POWER flag has been set or
not. Simply put: it breaks everything This patch therefore gets a
strongest *NACK* from me.

Thank you for backing up what I've already said about this patch (which
is why I stopped applying Ulf's MMC patches at this patch.)

I've also been concerned with the mere saving and restoring of the
clock and power registers in this patch - something which the ARM version
of the primecell does not actually support.

I've said that before...