PM: Reference counting of power.subsys_data
Since the power.subsys_data device field will be used by multiple
filesystems, introduce a reference counting mechanism for it to avoid
freeing it prematurely or changing its value at a wrong time.
Make the PM clocks management code that currently is the only user of
power.subsys_data use the new reference counting.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c
index b7f1db4..8383e24 100644
--- a/drivers/base/power/clock_ops.c
+++ b/drivers/base/power/clock_ops.c
@@ -140,12 +140,8 @@
void pm_clk_init(struct device *dev)
{
struct pm_subsys_data *psd = dev_to_psd(dev);
-
- if (!psd)
- return;
-
- INIT_LIST_HEAD(&psd->clock_list);
- spin_lock_init(&psd->lock);
+ if (psd)
+ INIT_LIST_HEAD(&psd->clock_list);
}
/**
@@ -157,16 +153,8 @@
*/
int pm_clk_create(struct device *dev)
{
- struct pm_subsys_data *psd;
-
- psd = kzalloc(sizeof(*psd), GFP_KERNEL);
- if (!psd) {
- dev_err(dev, "Not enough memory for PM clock data.\n");
- return -ENOMEM;
- }
- dev->power.subsys_data = psd;
- pm_clk_init(dev);
- return 0;
+ int ret = dev_pm_get_subsys_data(dev);
+ return ret < 0 ? ret : 0;
}
/**
@@ -185,8 +173,6 @@
if (!psd)
return;
- dev->power.subsys_data = NULL;
-
spin_lock_irq(&psd->lock);
list_for_each_entry_safe_reverse(ce, c, &psd->clock_list, node)
@@ -194,7 +180,7 @@
spin_unlock_irq(&psd->lock);
- kfree(psd);
+ dev_pm_put_subsys_data(dev);
}
#endif /* CONFIG_PM */