mmc: sdhci-acpi: enable sdhci-acpi device to suspend/resume asynchronously

This patch enables sdhci-acpi devices to suspend/resume asynchronously.
This will improve system suspend/resume speed. After enabling the
sdhci-acpi devices and all their child devices to suspend/resume
asynchronously on ASUS T100TA, the system suspend-to-idle time is
reduced from 1645ms to 1089ms, and the system resume time is reduced
from 940ms to 908ms.

Signed-off-by: Zhonghui Fu <zhonghui.fu@linux.intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/host/sdhci-acpi.c b/drivers/mmc/host/sdhci-acpi.c
index a5cda926d38eb23be20eece31c6b1ef0c44723a3..195ff0853dc838d7279c5feda871c3f7cd6633a0 100644 (file)
--- a/drivers/mmc/host/sdhci-acpi.c
+++ b/drivers/mmc/host/sdhci-acpi.c
@@ -418,6 +418,8 @@ static int sdhci_acpi_probe(struct platform_device *pdev)
                pm_runtime_enable(dev);
        }
 
+       device_enable_async_suspend(dev);
+
        return 0;
 
 err_free: