sh_mmcif / PM: Use PM QoS latency constraint

Make sh_mmcif call dev_pm_qos_expose_latency_limit() to expose
the PM QoS latency limit to user space and specify the initial
value of it as 100 microseconds.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
diff --git a/drivers/mmc/host/sh_mmcif.c b/drivers/mmc/host/sh_mmcif.c
index f5d8b53..a4ad93b 100644
--- a/drivers/mmc/host/sh_mmcif.c
+++ b/drivers/mmc/host/sh_mmcif.c
@@ -56,6 +56,7 @@
 #include <linux/mmc/sh_mmcif.h>
 #include <linux/pagemap.h>
 #include <linux/platform_device.h>
+#include <linux/pm_qos.h>
 #include <linux/pm_runtime.h>
 #include <linux/spinlock.h>
 #include <linux/module.h>
@@ -1347,6 +1348,8 @@
 
 	mmc_detect_change(host->mmc, 0);
 
+	dev_pm_qos_expose_latency_limit(&pdev->dev, 100);
+
 	dev_info(&pdev->dev, "driver version %s\n", DRIVER_VERSION);
 	dev_dbg(&pdev->dev, "chip ver H'%04x\n",
 		sh_mmcif_readl(host->addr, MMCIF_CE_VERSION) & 0x0000ffff);
@@ -1374,6 +1377,8 @@
 	host->dying = true;
 	pm_runtime_get_sync(&pdev->dev);
 
+	dev_pm_qos_hide_latency_limit(&pdev->dev);
+
 	mmc_remove_host(host->mmc);
 	sh_mmcif_writel(host->addr, MMCIF_CE_INT_MASK, MASK_ALL);