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Diffstat (limited to 'arch/powerpc/platforms/powernv/opal-sensor.c')
-rw-r--r--arch/powerpc/platforms/powernv/opal-sensor.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powernv/opal-sensor.c b/arch/powerpc/platforms/powernv/opal-sensor.c
new file mode 100644
index 000000000000..663cc9c65613
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/opal-sensor.c
@@ -0,0 +1,64 @@
+/*
+ * PowerNV sensor code
+ *
+ * Copyright (C) 2013 IBM
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/delay.h>
+#include <linux/mutex.h>
+#include <asm/opal.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
+ * device tree..
+ */
+int opal_get_sensor_data(u32 sensor_hndl, u32 *sensor_data)
+{
+ int ret, token;
+ struct opal_msg msg;
+
+ token = opal_async_get_token_interruptible();
+ if (token < 0) {
+ pr_err("%s: Couldn't get the token, returning\n", __func__);
+ ret = token;
+ goto out;
+ }
+
+ mutex_lock(&opal_sensor_mutex);
+ ret = opal_sensor_read(sensor_hndl, token, sensor_data);
+ if (ret != OPAL_ASYNC_COMPLETION)
+ goto out_token;
+
+ ret = opal_async_wait_response(token, &msg);
+ if (ret) {
+ pr_err("%s: Failed to wait for the async response, %d\n",
+ __func__, ret);
+ goto out_token;
+ }
+
+ ret = msg.params[1];
+
+out_token:
+ mutex_unlock(&opal_sensor_mutex);
+ opal_async_release_token(token);
+out:
+ return ret;
+}
+EXPORT_SYMBOL_GPL(opal_get_sensor_data);