MMC host need to power ungate host each time before sending a request and
try to power gate host each time after the request is done.
MMC host has a sysfs interface to let user specify the auto suspended delay.
Each slot of the host controller can have a different delay for runtime
suspended.
Signed-off-by: Chuanxiao Dong <chuanxiao.dong@xxxxxxxxx>
---
drivers/mmc/core/core.c | 15 +++++++++++++++
drivers/mmc/core/host.c | 21 +++++++++++++++++++++
2 files changed, 36 insertions(+), 0 deletions(-)
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 6625c05..e296c5a 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -133,6 +133,9 @@ void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
mrq->done(mrq);
mmc_host_clk_gate(host);
+
+ /* put the host after using */
+ pm_runtime_put(&host->class_dev);
}
}
@@ -150,6 +153,12 @@ mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
mmc_hostname(host), mrq->cmd->opcode,
mrq->cmd->arg, mrq->cmd->flags);
+ /*
+ * Before touch any of host controller registers,
+ * driver should make sure the host is powered up
+ */
+ pm_runtime_get_sync(&host->class_dev);
+
if (mrq->data) {
pr_debug("%s: blksz %d blocks %d flags %08x "
"tsac %d ms nsac %d\n",
@@ -1522,6 +1531,9 @@ void mmc_rescan(struct work_struct *work)
if (host->rescan_disable)
return;
+ /* power up host controller first */
+ pm_runtime_get_sync(&host->class_dev);
+
mmc_bus_get(host);
/*
@@ -1564,6 +1576,9 @@ void mmc_rescan(struct work_struct *work)
mmc_release_host(host);
out:
+ /* power off host controller */
+ pm_runtime_put(&host->class_dev);
+
if (host->caps & MMC_CAP_NEEDS_POLL)
mmc_schedule_delayed_work(&host->detect, HZ);
}
diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
index b3ac6c5..a27b811 100644
--- a/drivers/mmc/core/host.c
+++ b/drivers/mmc/core/host.c
@@ -19,6 +19,7 @@
#include <linux/leds.h>
#include <linux/slab.h>
#include <linux/suspend.h>
+#include <linux/pm_runtime.h>
#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
@@ -28,6 +29,14 @@
#define cls_dev_to_mmc_host(d) container_of(d, struct mmc_host, class_dev)
+static const struct dev_pm_ops host_pm = {
+ SET_RUNTIME_PM_OPS(
+ pm_generic_runtime_suspend,
+ pm_generic_runtime_resume,
+ pm_generic_runtime_idle
+ )
+};
+
static void mmc_host_classdev_release(struct device *dev)
{
struct mmc_host *host = cls_dev_to_mmc_host(dev);
@@ -37,6 +46,7 @@ static void mmc_host_classdev_release(struct device *dev)
static struct class mmc_host_class = {
.name = "mmc_host",
.dev_release = mmc_host_classdev_release,
+ .pm = &host_pm,
};
int mmc_register_host_class(void)
@@ -334,6 +344,15 @@ int mmc_add_host(struct mmc_host *host)
if (err)
return err;
+ /* enable runtime pm */
+ err = pm_runtime_set_active(&host->class_dev);
+ if (err)
+ pr_err("err is %d when active mmc host\n", err);
+ else {
+ pm_runtime_enable(&host->class_dev);
+ pm_runtime_set_autosuspend_delay(&host->class_dev, 100);
+ }
+
#ifdef CONFIG_DEBUG_FS
mmc_add_host_debugfs(host);
#endif
@@ -363,6 +382,8 @@ void mmc_remove_host(struct mmc_host *host)
mmc_remove_host_debugfs(host);
#endif
+ pm_runtime_disable(&host->class_dev);
+
device_del(&host->class_dev);
led_trigger_unregister_simple(host->led);
--
1.6.6.1
--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
