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path: root/drivers/mmc/core/sdio_bus.c
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Diffstat (limited to 'drivers/mmc/core/sdio_bus.c')
-rw-r--r--drivers/mmc/core/sdio_bus.c85
1 files changed, 83 insertions, 2 deletions
diff --git a/drivers/mmc/core/sdio_bus.c b/drivers/mmc/core/sdio_bus.c
index 4a890dcb95ab..2716c7ab6bbf 100644
--- a/drivers/mmc/core/sdio_bus.c
+++ b/drivers/mmc/core/sdio_bus.c
@@ -14,6 +14,7 @@
#include <linux/device.h>
#include <linux/err.h>
#include <linux/slab.h>
+#include <linux/pm_runtime.h>
#include <linux/mmc/card.h>
#include <linux/mmc/sdio_func.h>
@@ -125,21 +126,46 @@ static int sdio_bus_probe(struct device *dev)
if (!id)
return -ENODEV;
+ /* Unbound SDIO functions are always suspended.
+ * During probe, the function is set active and the usage count
+ * is incremented. If the driver supports runtime PM,
+ * it should call pm_runtime_put_noidle() in its probe routine and
+ * pm_runtime_get_noresume() in its remove routine.
+ */
+ ret = pm_runtime_get_sync(dev);
+ if (ret < 0)
+ goto out;
+
/* Set the default block size so the driver is sure it's something
* sensible. */
sdio_claim_host(func);
ret = sdio_set_block_size(func, 0);
sdio_release_host(func);
if (ret)
- return ret;
+ goto disable_runtimepm;
+
+ ret = drv->probe(func, id);
+ if (ret)
+ goto disable_runtimepm;
- return drv->probe(func, id);
+ return 0;
+
+disable_runtimepm:
+ pm_runtime_put_noidle(dev);
+out:
+ return ret;
}
static int sdio_bus_remove(struct device *dev)
{
struct sdio_driver *drv = to_sdio_driver(dev->driver);
struct sdio_func *func = dev_to_sdio_func(dev);
+ int ret;
+
+ /* Make sure card is powered before invoking ->remove() */
+ ret = pm_runtime_get_sync(dev);
+ if (ret < 0)
+ goto out;
drv->remove(func);
@@ -151,9 +177,63 @@ static int sdio_bus_remove(struct device *dev)
sdio_release_host(func);
}
+ /* First, undo the increment made directly above */
+ pm_runtime_put_noidle(dev);
+
+ /* Then undo the runtime PM settings in sdio_bus_probe() */
+ pm_runtime_put_noidle(dev);
+
+out:
+ return ret;
+}
+
+#ifdef CONFIG_PM_RUNTIME
+
+static int sdio_bus_pm_prepare(struct device *dev)
+{
+ /*
+ * Resume an SDIO device which was suspended at run time at this
+ * point, in order to allow standard SDIO suspend/resume paths
+ * to keep working as usual.
+ *
+ * Ultimately, the SDIO driver itself will decide (in its
+ * suspend handler, or lack thereof) whether the card should be
+ * removed or kept, and if kept, at what power state.
+ *
+ * At this point, PM core have increased our use count, so it's
+ * safe to directly resume the device. After system is resumed
+ * again, PM core will drop back its runtime PM use count, and if
+ * needed device will be suspended again.
+ *
+ * The end result is guaranteed to be a power state that is
+ * coherent with the device's runtime PM use count.
+ *
+ * The return value of pm_runtime_resume is deliberately unchecked
+ * since there is little point in failing system suspend if a
+ * device can't be resumed.
+ */
+ pm_runtime_resume(dev);
+
return 0;
}
+static const struct dev_pm_ops sdio_bus_pm_ops = {
+ SET_RUNTIME_PM_OPS(
+ pm_generic_runtime_suspend,
+ pm_generic_runtime_resume,
+ pm_generic_runtime_idle
+ )
+ .prepare = sdio_bus_pm_prepare,
+};
+
+#define SDIO_PM_OPS_PTR (&sdio_bus_pm_ops)
+
+#else /* !CONFIG_PM_RUNTIME */
+
+#define SDIO_PM_OPS_PTR NULL
+
+#endif /* !CONFIG_PM_RUNTIME */
+
static struct bus_type sdio_bus_type = {
.name = "sdio",
.dev_attrs = sdio_dev_attrs,
@@ -161,6 +241,7 @@ static struct bus_type sdio_bus_type = {
.uevent = sdio_bus_uevent,
.probe = sdio_bus_probe,
.remove = sdio_bus_remove,
+ .pm = SDIO_PM_OPS_PTR,
};
int sdio_register_bus(void)