[PATCH 1/2] firmware: arm_scmi: Fetch and store sensor scale

[Florian Fainelli <f.fainelli@gmail.com>]

In preparation for dealing with scales within the SCMI HWMON driver,
fetch and store the sensor unit scale into the scmi_sensor_info
structure.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
 drivers/firmware/arm_scmi/sensors.c | 7 ++++++-
 include/linux/scmi_protocol.h       | 1 +
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/firmware/arm_scmi/sensors.c b/drivers/firmware/arm_scmi/sensors.c
index b53d5cc9c9f6..f324f0a13ebe 100644
--- a/drivers/firmware/arm_scmi/sensors.c
+++ b/drivers/firmware/arm_scmi/sensors.c
@@ -33,7 +33,8 @@ struct scmi_msg_resp_sensor_description {
 #define NUM_TRIP_POINTS(x)	(((x) >> 4) & 0xff)
 		__le32 attributes_high;
 #define SENSOR_TYPE(x)		((x) & 0xff)
-#define SENSOR_SCALE(x)		(((x) >> 11) & 0x3f)
+#define SENSOR_SCALE_MASK	0x3f
+#define SENSOR_SCALE(x)		(((x) >> 11) & SENSOR_SCALE_MASK)
 #define SENSOR_UPDATE_SCALE(x)	(((x) >> 22) & 0x1f)
 #define SENSOR_UPDATE_BASE(x)	(((x) >> 27) & 0x1f)
 		    u8 name[SCMI_MAX_STR_SIZE];
@@ -140,6 +141,10 @@ static int scmi_sensor_description_get(const struct scmi_handle *handle,
 			s = &si->sensors[desc_index + cnt];
 			s->id = le32_to_cpu(buf->desc[cnt].id);
 			s->type = SENSOR_TYPE(attrh);
+			s->scale = SENSOR_SCALE(attrh);
+			/* Sign extend to a full u8 */
+			if (s->scale & ((SENSOR_SCALE_MASK + 1) >> 1))
+				s->scale |= GENMASK(7, 6);
 			strlcpy(s->name, buf->desc[cnt].name, SCMI_MAX_STR_SIZE);
 		}
 
diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h
index 3105055c00a7..7746f171f108 100644
--- a/include/linux/scmi_protocol.h
+++ b/include/linux/scmi_protocol.h
@@ -144,6 +144,7 @@ struct scmi_power_ops {
 struct scmi_sensor_info {
 	u32 id;
 	u8 type;
+	u8 scale;
 	char name[SCMI_MAX_STR_SIZE];
 };
 
-- 
2.17.1