| Message ID | 20211220174155.40239-2-cristian.marussi@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Sensor readings fixes | expand |
diff --git a/drivers/firmware/arm_scmi/sensors.c b/drivers/firmware/arm_scmi/sensors.c index cdbb287bd8bc..f3952f1d9f61 100644 --- a/drivers/firmware/arm_scmi/sensors.c +++ b/drivers/firmware/arm_scmi/sensors.c @@ -730,6 +730,14 @@ static int scmi_sensor_reading_get(const struct scmi_protocol_handle *ph, *value = get_unaligned_le64(t->rx.buf); } + if (!ret && si->version > SCMIv2_SENSOR_PROTOCOL && *value & BIT(63)) { + dev_warn_once(ph->dev, + "SCMI FW Sensor version:0x%X reported negative value %ld\n", + si->version, (long)*value); + *value = 0; + ret = -EIO; + } + ph->xops->xfer_put(ph, t); return ret; }
When the backing SCMI Platform supports a Sensor protocol whose version is greater than SCMI v2.0 (0x10000), the underlying SCMI SENSOR_READING_GET command will report sensors readings no more as unsigned but as signed values. A new scmi_reading_get_timestamped operation was added to properly handle this and other changes like timestamps and multi-axis sensors; on the other side the Sensor scmi_reading_get protocol operation was kepts as it was for backward compatibility and so it stil reports values as unsigned, but no check was added to detect the situation in which a newer FW could try to report negative values over an unsigned quantity. Filter out negative values in scmi_reading_get, reporting an error, when the SCMI FW version is greater than V2.0 and a negative value has been received. Reported-by: Nicola Mazzucato <nicola.mazzucato@arm.com> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> --- Note that, till now, HWMON SCMI driver was silently interpreting u64 as s64, so after this change whenever a FW >2.0 is used it won't be possible anymore to report negative values in HWMON. --- drivers/firmware/arm_scmi/sensors.c | 8 ++++++++ 1 file changed, 8 insertions(+)