Re: [PATCH 1/2] firmware: arm_scpi: add support for 64-bit sensor values

[Guenter Roeck <linux@roeck-us.net>]

On 02/09/2016 06:32 AM, Sudeep Holla wrote:
> SCPI specification version 1.1 extended the sensor from 32-bit to 64-bit
> values in order to accommodate new sensor class with 64-bit requirements
>
> Since the SCPI driver sets the higher 32-bit for older protocol version
> to zeros, there's no need to explicitly check the SCPI protocol version
> and the backward compatibility is maintainted.
>
> Cc: Punit Agrawal <punit.agrawal@arm.com>
> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

Acked-by: Guenter Roeck <linux@roeck-us.net>

> ---
>   drivers/firmware/arm_scpi.c   | 8 +++++---
>   drivers/hwmon/scpi-hwmon.c    | 6 +++---
>   include/linux/scpi_protocol.h | 2 +-
>   3 files changed, 9 insertions(+), 7 deletions(-)
>
> Hi Guenter,
>
> Since I have couple of other fixes for SCPI driver, if you can provide
> your ACKs to this couple of patches after your review, I can take all of
> them together via ARM-SoC if that's fine with you.
>
> Regards,
> Sudeep
>
> diff --git a/drivers/firmware/arm_scpi.c b/drivers/firmware/arm_scpi.c
> index c32ac6e61ba2..7e3e595c9f30 100644
> --- a/drivers/firmware/arm_scpi.c
> +++ b/drivers/firmware/arm_scpi.c
> @@ -231,7 +231,8 @@ struct _scpi_sensor_info {
>   };
>
>   struct sensor_value {
> -	__le32 val;
> +	__le32 lo_val;
> +	__le32 hi_val;
>   } __packed;
>
>   static struct scpi_drvinfo *scpi_info;
> @@ -525,7 +526,7 @@ static int scpi_sensor_get_info(u16 sensor_id, struct scpi_sensor_info *info)
>   	return ret;
>   }
>
> -int scpi_sensor_get_value(u16 sensor, u32 *val)
> +int scpi_sensor_get_value(u16 sensor, u64 *val)
>   {
>   	__le16 id = cpu_to_le16(sensor);
>   	struct sensor_value buf;
> @@ -534,7 +535,8 @@ int scpi_sensor_get_value(u16 sensor, u32 *val)
>   	ret = scpi_send_message(SCPI_CMD_SENSOR_VALUE, &id, sizeof(id),
>   				&buf, sizeof(buf));
>   	if (!ret)
> -		*val = le32_to_cpu(buf.val);
> +		*val = (u64)le32_to_cpu(buf.hi_val) << 32 |
> +			le32_to_cpu(buf.lo_val);
>
>   	return ret;
>   }
> diff --git a/drivers/hwmon/scpi-hwmon.c b/drivers/hwmon/scpi-hwmon.c
> index 7e20567bc369..7101b14b5137 100644
> --- a/drivers/hwmon/scpi-hwmon.c
> +++ b/drivers/hwmon/scpi-hwmon.c
> @@ -52,7 +52,7 @@ static int scpi_read_temp(void *dev, int *temp)
>   	struct scpi_sensors *scpi_sensors = zone->scpi_sensors;
>   	struct scpi_ops *scpi_ops = scpi_sensors->scpi_ops;
>   	struct sensor_data *sensor = &scpi_sensors->data[zone->sensor_id];
> -	u32 value;
> +	u64 value;
>   	int ret;
>
>   	ret = scpi_ops->sensor_get_value(sensor->info.sensor_id, &value);
> @@ -70,7 +70,7 @@ scpi_show_sensor(struct device *dev, struct device_attribute *attr, char *buf)
>   	struct scpi_sensors *scpi_sensors = dev_get_drvdata(dev);
>   	struct scpi_ops *scpi_ops = scpi_sensors->scpi_ops;
>   	struct sensor_data *sensor;
> -	u32 value;
> +	u64 value;
>   	int ret;
>
>   	sensor = container_of(attr, struct sensor_data, dev_attr_input);
> @@ -79,7 +79,7 @@ scpi_show_sensor(struct device *dev, struct device_attribute *attr, char *buf)
>   	if (ret)
>   		return ret;
>
> -	return sprintf(buf, "%u\n", value);
> +	return sprintf(buf, "%llu\n", value);
>   }
>
>   static ssize_t
> diff --git a/include/linux/scpi_protocol.h b/include/linux/scpi_protocol.h
> index 72ce932c69b2..ecd248d46281 100644
> --- a/include/linux/scpi_protocol.h
> +++ b/include/linux/scpi_protocol.h
> @@ -68,7 +68,7 @@ struct scpi_ops {
>   	struct scpi_dvfs_info *(*dvfs_get_info)(u8);
>   	int (*sensor_get_capability)(u16 *sensors);
>   	int (*sensor_get_info)(u16 sensor_id, struct scpi_sensor_info *);
> -	int (*sensor_get_value)(u16, u32 *);
> +	int (*sensor_get_value)(u16, u64 *);
>   };
>
>   #if IS_REACHABLE(CONFIG_ARM_SCPI_PROTOCOL)
>