The opal sensor mutex protects the opal_sensor_read call which
can return a OPAL_BUSY code on IBM Power systems if a previous
request is in progress.
This can be handled at user level with a retry.
Signed-off-by: Cédric Le Goater <c...@fr.ibm.com>
---
Changes since v2 :
- removed a goto label
arch/powerpc/platforms/powernv/opal-sensor.c | 9 +--------
1 file changed, 1 insertion(+), 8 deletions(-)
Index: linux.git/arch/powerpc/platforms/powernv/opal-sensor.c
===================================================================
--- linux.git.orig/arch/powerpc/platforms/powernv/opal-sensor.c
+++ linux.git/arch/powerpc/platforms/powernv/opal-sensor.c
@@ -19,13 +19,10 @@
*/
#include <linux/delay.h>
-#include <linux/mutex.h>
#include <linux/of_platform.h>
#include <asm/opal.h>
#include <asm/machdep.h>
-static DEFINE_MUTEX(opal_sensor_mutex);
-
/*
* This will return sensor information to driver based on the requested sensor
* handle. A handle is an opaque id for the powernv, read by the driver from
the
@@ -40,11 +37,9 @@ int opal_get_sensor_data(u32 sensor_hndl
token = opal_async_get_token_interruptible();
if (token < 0) {
pr_err("%s: Couldn't get the token, returning\n", __func__);
- ret = token;
- goto out;
+ return token;
}
- mutex_lock(&opal_sensor_mutex);
ret = opal_sensor_read(sensor_hndl, token, &data);
switch (ret) {
case OPAL_ASYNC_COMPLETION:
@@ -70,9 +65,7 @@ int opal_get_sensor_data(u32 sensor_hndl
}
out_token:
- mutex_unlock(&opal_sensor_mutex);
opal_async_release_token(token);
-out:
return ret;
}
EXPORT_SYMBOL_GPL(opal_get_sensor_data);
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