On 17.10.21 14:51, Jonathan Cameron wrote:
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On Fri, 8 Oct 2021 21:28:26 +0300
Andriy Tryshnivskyy <andriy.tryshnivskyy@xxxxxxxxxxxxxxx> wrote:
Add scmi_iio_get_raw() to read "raw" attribute.
Signed-off-by: Andriy Tryshnivskyy <andriy.tryshnivskyy@xxxxxxxxxxxxxxx>
---
For a single patch series, it is better to put a change log in the patch (here)
Whilst I can see why you would use this approach rather than the read_raw callback
there are significant disadvantages in doing so. The channel can't be used
by in kernel users such as iio-hwmon. That may cause you more trouble than
it is worth in the long run.
Note that you could also define a new IIO_VAL type to still use the two
(possibly) 32 bit values and return a 64 bit value. That way, with appropriate
additions in the consumer drivers the channel could still be used.
IIO_VAL_INT_64 perhaps with val as the lower 32 bits and val2 as the upper
with appropriate care around the sign.
Hi Jonathan,
In the past I also was thinking about introducing a new type to return 64 bits value - IIO_VAL_INT_LONG.
However since it requires changes in
include/linux/iio/types.h
drivers/iio/industrialio-core.c
I thought it will be harder to get approval for this approach.
But now it seems there is no other way. So I will prepare a new patch version soon which introduces IIO_VAL_INT_LONG.
Thank you for your review!
drivers/iio/common/scmi_sensors/scmi_iio.c | 61 ++++++++++++++++++++++
1 file changed, 61 insertions(+)
diff --git a/drivers/iio/common/scmi_sensors/scmi_iio.c b/drivers/iio/common/scmi_sensors/scmi_iio.c
index 7cf2bf282cef..691cbbd61e3a 100644
--- a/drivers/iio/common/scmi_sensors/scmi_iio.c
+++ b/drivers/iio/common/scmi_sensors/scmi_iio.c
@@ -311,6 +311,62 @@ static const struct iio_info scmi_iio_info = {
.write_raw = scmi_iio_write_raw,
};
+static ssize_t scmi_iio_get_raw(struct iio_dev *iio_dev, uintptr_t private,
+ const struct iio_chan_spec *chan, char *buf)
+{
+ struct scmi_iio_priv *sensor = iio_priv(iio_dev);
+ int err;
+ u32 sensor_config;
+ struct scmi_sensor_reading readings[SCMI_IIO_NUM_OF_AXIS];
+ int len = 0;
+
+ err = iio_device_claim_direct_mode(iio_dev);
+ if (err) {
+ dev_err(&iio_dev->dev,
+ "Error in claiming direct mode for sensor %s err %d",
+ sensor->sensor_info->name, err);
It's not an error, it just means the device is busy, so at most dev_info()
or just rely on userspace correctly interpreting EBUSY.
Agree. Will use dev_info().
Thank you!
+ goto err_release;
+ }
+
+ sensor_config = FIELD_PREP(SCMI_SENS_CFG_SENSOR_ENABLED_MASK,
+ SCMI_SENS_CFG_SENSOR_ENABLE);
+ err = sensor->sensor_ops->config_set(
+ sensor->ph, sensor->sensor_info->id, sensor_config);
+ if (err) {
+ dev_err(&iio_dev->dev, "Error in enabling sensor %s err %d",
+ sensor->sensor_info->name, err);
+ goto err_release;
+ }
+
+ err = sensor->sensor_ops->reading_get_timestamped(
+ sensor->ph, sensor->sensor_info->id,
+ sensor->sensor_info->num_axis, readings);
+ if (err) {
+ dev_err(&iio_dev->dev,
+ "Error in reading raw attribute for sensor %s err %d",
+ sensor->sensor_info->name, err);
+ goto err_release;
+ }
+
+ sensor_config = FIELD_PREP(SCMI_SENS_CFG_SENSOR_ENABLED_MASK,
+ SCMI_SENS_CFG_SENSOR_DISABLE);
+ err = sensor->sensor_ops->config_set(
+ sensor->ph, sensor->sensor_info->id, sensor_config);
+ if (err) {
+ dev_err(&iio_dev->dev, "Error in disabling sensor %s err %d",
+ sensor->sensor_info->name, err);
+ goto err_release;
+ }
+
+ len = scnprintf(buf, PAGE_SIZE, "%lld\n",
+ readings[chan->scan_index].value);
+
+err_release:
+ iio_device_release_direct_mode(iio_dev);
+
+ return len;
+}
+
static ssize_t scmi_iio_get_raw_available(struct iio_dev *iio_dev,
uintptr_t private,
const struct iio_chan_spec *chan,
@@ -355,6 +411,11 @@ static ssize_t scmi_iio_get_raw_available(struct iio_dev *iio_dev,
}
static const struct iio_chan_spec_ext_info scmi_iio_ext_info[] = {
+ {
+ .name = "raw",
+ .read = scmi_iio_get_raw,
+ .shared = IIO_SEPARATE,
+ },
{
.name = "raw_available",
.read = scmi_iio_get_raw_available,
