When sdhci is runtime_suspended, it can still receive a wake-up
because of card insertion.
The wake-up will then be signaled by an interrupt which cannot be serviced
immediatly, as the device is powered off, and register are not accessibles.

We cannot call pm_runtime_get_sync() in irq context as on some architecture 
(e.g. intel_mid),
runtime_resume can lead to too much latency, due to e.g. PLL warm-up and such 
aggressive
power gating.

We temporarly disable the interrupt, and trigger a runtime_resume of the device
The interrupt will be re-enabled when resume is finished.

Signed-off-by: Pierre Tardy <tar...@gmail.com>
---
 drivers/mmc/host/sdhci-pci.c |    8 +-------
 drivers/mmc/host/sdhci.c     |   30 +++++++++++++++++++++++++++++-
 include/linux/mmc/sdhci.h    |    2 ++
 scripts/checkpatch.pl        |    6 +++---
 4 files changed, 35 insertions(+), 11 deletions(-)

diff --git a/drivers/mmc/host/sdhci-pci.c b/drivers/mmc/host/sdhci-pci.c
index 1b5e70b..fc3d2e1 100644
--- a/drivers/mmc/host/sdhci-pci.c
+++ b/drivers/mmc/host/sdhci-pci.c
@@ -1166,13 +1166,7 @@ static int sdhci_pci_runtime_suspend(struct device *dev)
        }
 
        pci_save_state(pdev);
-       if (pm_flags & MMC_PM_KEEP_POWER) {
-               if (pm_flags & MMC_PM_WAKE_SDIO_IRQ)
-                       pci_enable_wake(pdev, PCI_D3hot, 1);
-       } else {
-               pci_enable_wake(pdev, PCI_D3hot, 0);
-               pci_disable_device(pdev);
-       }
+       pci_enable_wake(pdev, PCI_D3hot, 1);
        pci_set_power_state(pdev, PCI_D3hot);
 
        return 0;
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 735c3f7..85a1956 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1599,6 +1599,21 @@ static irqreturn_t sdhci_irq(int irq, void *dev_id)
        u32 intmask;
        int cardint = 0;
 
+       /* we might come from a sd insertion or sdio irq wake.. */
+       if (pm_runtime_suspended()) {
+               host->waking_up = 1;
+               /* Note that we disable temporarly the interrupt until we do the
+                * resume. If we don't then we'll get constantly interrupted
+                * until we actually resume.
+                *
+                * as the irq is shared, this might not be very friendly to our
+                * irq sharers but the pm_runtime workqueue should really be
+                * called soon.
+                */
+               disable_irq_nosync(irq);
+               pm_runtime_get(host->mmc->parent);
+               return IRQ_NONE;
+       }
        spin_lock(&host->lock);
 
        intmask = sdhci_readl(host, SDHCI_INT_STATUS);
@@ -1747,7 +1762,12 @@ EXPORT_SYMBOL_GPL(sdhci_enable_irq_wakeups);
 
 int sdhci_runtime_suspend(struct sdhci_host *host)
 {
-       /* nothing to do yet */
+       u8 val;
+       /* make sure we wake up on sdcard insert/remove enabled */
+       val = SDHCI_WAKE_ON_INSERT | SDHCI_WAKE_ON_REMOVE;
+       if (host->mmc->pm_flags & MMC_PM_WAKE_SDIO_IRQ)
+               val |= SDHCI_WAKE_ON_INT;
+       sdhci_writeb(host, val, SDHCI_WAKE_UP_CONTROL);
        return 0;
 }
 
@@ -1768,6 +1788,14 @@ int sdhci_runtime_resume(struct sdhci_host *host)
        sdhci_set_ios(host->mmc, &host->mmc->ios);
        mmiowb();
 
+       if (host->waking_up) {
+               host->waking_up = 0;
+               /* Re-enable the irq now we are perfectly resumed.
+                * Any yet unhandled interrupt (i.e. the wake) will retrigger
+                * irq
+                */
+               irq_enable(host->irq);
+       }
        return ret;
 }
 EXPORT_SYMBOL_GPL(sdhci_runtime_resume);
diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
index a38d040..6a3c6af 100644
--- a/include/linux/mmc/sdhci.h
+++ b/include/linux/mmc/sdhci.h
@@ -146,6 +146,8 @@ struct sdhci_host {
        unsigned int            ocr_avail_sd;
        unsigned int            ocr_avail_mmc;
 
+       bool                    waking_up;
+
        unsigned long private[0] ____cacheline_aligned;
 };
 #endif /* __SDHCI_H */
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index e3c7fc0..17aeda3 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -1325,8 +1325,8 @@ sub process {
                $prefix = "$filename:$realline: " if ($emacs && $file);
                $prefix = "$filename:$linenr: " if ($emacs && !$file);
 
-               $here = "#$linenr: " if (!$file);
-               $here = "#$realline: " if ($file);
+               $here = "" if (!$file);
+               $here = "" if ($file);
 
                # extract the filename as it passes
                if ($line =~ /^diff --git.*?(\S+)$/) {
@@ -1349,7 +1349,7 @@ sub process {
                        next;
                }
 
-               $here .= "FILE: $realfile:$realline:" if ($realcnt != 0);
+               $here .= "$realfile:$realline:" if ($realcnt != 0);
 
                my $hereline = "$here\n$rawline\n";
                my $herecurr = "$here\n$rawline\n";
-- 
1.7.1

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