| Message ID | ee20a9b8d1700a3987570d2edd28fe9ac9e73123.1560848479.git.fabien.lahoudere@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Expose cros_ec_sensors frequency range via iio sysfs | expand |
On Tue, 18 Jun 2019 11:06:38 +0200 Fabien Lahoudere <fabien.lahoudere@collabora.com> wrote: > Embedded controller return minimum and maximum frequencies, unfortunately > we have no way to know the step for all available frequencies. > Even if not complete, we can return a list of known values using the > standard read_avail callback (IIO_CHAN_INFO_SAMP_FREQ) to provide them to > userland. > > Now cros_ec_* sensors provides frequencies values in sysfs like this: > "0 min max". > > 0 is always true to disable the sensor. Hmm. 0 frequency feels like a kind of non standard use of the ABI. I suppose it's fairly logical and it does no harm if userspace never uses it so I guess we can let this use in without updating the docs. I'd like some feedback from the chromeos side on whether this is a sensible way of representing things? Note that generic userspace will only pick one of those values, it won't magically decide to go for somewhere inbetween. Jonathan > > Signed-off-by: Fabien Lahoudere <fabien.lahoudere@collabora.com> > --- > .../cros_ec_sensors/cros_ec_sensors_core.c | 22 +++++++++++++++++++ > .../linux/iio/common/cros_ec_sensors_core.h | 4 +++- > 2 files changed, 25 insertions(+), 1 deletion(-) > > diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c > index 2ce077b576a4..8df82b675752 100644 > --- a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c > +++ b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c > @@ -10,6 +10,7 @@ > #include <linux/iio/buffer.h> > #include <linux/iio/common/cros_ec_sensors_core.h> > #include <linux/iio/iio.h> > +#include <linux/iio/sysfs.h> > #include <linux/iio/kfifo_buf.h> > #include <linux/iio/trigger_consumer.h> > #include <linux/iio/triggered_buffer.h> > @@ -86,6 +87,26 @@ static int cros_ec_get_host_cmd_version_mask(struct cros_ec_device *ec_dev, > return ret; > } > > +static int cros_ec_read_avail(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + const int **vals, > + int *type, > + int *length, > + long mask) > +{ > + struct cros_ec_sensors_core_state *state = iio_priv(indio_dev); > + > + switch (mask) { > + case IIO_CHAN_INFO_SAMP_FREQ: > + *length = 3; > + *vals = (const int *)&state->frequency_range; > + *type = IIO_VAL_INT; > + return IIO_AVAIL_LIST; > + } > + > + return -EINVAL; > +} > + > int cros_ec_sensors_core_init(struct platform_device *pdev, > int num_channels, > bool physical_device) > @@ -161,6 +182,7 @@ int cros_ec_sensors_core_init(struct platform_device *pdev, > } > } > > + state->info.read_avail = cros_ec_read_avail; > indio_dev->info = &state->info; > > /* Timestamp channel */ > diff --git a/include/linux/iio/common/cros_ec_sensors_core.h b/include/linux/iio/common/cros_ec_sensors_core.h > index 89937ad242ef..5fa9ba5332e0 100644 > --- a/include/linux/iio/common/cros_ec_sensors_core.h > +++ b/include/linux/iio/common/cros_ec_sensors_core.h > @@ -140,7 +140,9 @@ int cros_ec_sensors_core_register(struct platform_device *pdev, > channel[idx].scan_type.shift = 0;\ > channel[idx].scan_index = idx;\ > channel[idx].ext_info = cros_ec_sensors_ext_info;\ > - channel[idx].scan_type.sign = 'u'; > + channel[idx].scan_type.sign = 'u';\ > + channel[idx].info_mask_shared_by_all_available = \ > + BIT(IIO_CHAN_INFO_SAMP_FREQ); > > /** > * cros_ec_motion_send_host_cmd() - send motion sense host command
diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c index 2ce077b576a4..8df82b675752 100644 --- a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c +++ b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c @@ -10,6 +10,7 @@ #include <linux/iio/buffer.h> #include <linux/iio/common/cros_ec_sensors_core.h> #include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> #include <linux/iio/kfifo_buf.h> #include <linux/iio/trigger_consumer.h> #include <linux/iio/triggered_buffer.h> @@ -86,6 +87,26 @@ static int cros_ec_get_host_cmd_version_mask(struct cros_ec_device *ec_dev, return ret; } +static int cros_ec_read_avail(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int **vals, + int *type, + int *length, + long mask) +{ + struct cros_ec_sensors_core_state *state = iio_priv(indio_dev); + + switch (mask) { + case IIO_CHAN_INFO_SAMP_FREQ: + *length = 3; + *vals = (const int *)&state->frequency_range; + *type = IIO_VAL_INT; + return IIO_AVAIL_LIST; + } + + return -EINVAL; +} + int cros_ec_sensors_core_init(struct platform_device *pdev, int num_channels, bool physical_device) @@ -161,6 +182,7 @@ int cros_ec_sensors_core_init(struct platform_device *pdev, } } + state->info.read_avail = cros_ec_read_avail; indio_dev->info = &state->info; /* Timestamp channel */ diff --git a/include/linux/iio/common/cros_ec_sensors_core.h b/include/linux/iio/common/cros_ec_sensors_core.h index 89937ad242ef..5fa9ba5332e0 100644 --- a/include/linux/iio/common/cros_ec_sensors_core.h +++ b/include/linux/iio/common/cros_ec_sensors_core.h @@ -140,7 +140,9 @@ int cros_ec_sensors_core_register(struct platform_device *pdev, channel[idx].scan_type.shift = 0;\ channel[idx].scan_index = idx;\ channel[idx].ext_info = cros_ec_sensors_ext_info;\ - channel[idx].scan_type.sign = 'u'; + channel[idx].scan_type.sign = 'u';\ + channel[idx].info_mask_shared_by_all_available = \ + BIT(IIO_CHAN_INFO_SAMP_FREQ); /** * cros_ec_motion_send_host_cmd() - send motion sense host command
Embedded controller return minimum and maximum frequencies, unfortunately we have no way to know the step for all available frequencies. Even if not complete, we can return a list of known values using the standard read_avail callback (IIO_CHAN_INFO_SAMP_FREQ) to provide them to userland. Now cros_ec_* sensors provides frequencies values in sysfs like this: "0 min max". 0 is always true to disable the sensor. Signed-off-by: Fabien Lahoudere <fabien.lahoudere@collabora.com> --- .../cros_ec_sensors/cros_ec_sensors_core.c | 22 +++++++++++++++++++ .../linux/iio/common/cros_ec_sensors_core.h | 4 +++- 2 files changed, 25 insertions(+), 1 deletion(-)