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Subject[PATCH v2] drivers/base: use READ_ONCE instead of deprecated ACCESS_ONCE
With the new standardized functions, we can replace all ACCESS_ONCE()
calls across relevant drivers/base/.

ACCESS_ONCE() does not work reliably on non-scalar types. For example
gcc 4.6 and 4.7 might remove the volatile tag for such accesses during
the SRA (scalar replacement of aggregates) step:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145

Update the new calls regardless of if it is a scalar type, this is
cleaner than having three alternatives.

Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
---
drivers/base/core.c | 2 +-
drivers/base/power/runtime.c | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/base/core.c b/drivers/base/core.c
index ce057a568673..c0b3a2a03d72 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -101,7 +101,7 @@ const char *dev_driver_string(const struct device *dev)
* so be careful about accessing it. dev->bus and dev->class should
* never change once they are set, so they don't need special care.
*/
- drv = ACCESS_ONCE(dev->driver);
+ drv = READ_ONCE(dev->driver);
return drv ? drv->name :
(dev->bus ? dev->bus->name :
(dev->class ? dev->class->name : ""));
diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index 60ebb04d8140..747c19286250 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -132,11 +132,11 @@ unsigned long pm_runtime_autosuspend_expiration(struct device *dev)
if (!dev->power.use_autosuspend)
goto out;

- autosuspend_delay = ACCESS_ONCE(dev->power.autosuspend_delay);
+ autosuspend_delay = READ_ONCE(dev->power.autosuspend_delay);
if (autosuspend_delay < 0)
goto out;

- last_busy = ACCESS_ONCE(dev->power.last_busy);
+ last_busy = READ_ONCE(dev->power.last_busy);
elapsed = jiffies - last_busy;
if (elapsed < 0)
goto out; /* jiffies has wrapped around. */
--
2.6.6
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