Message ID | 20181203065707.3428-1-drake@endlessm.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | Re: Inconsistent SMO8840 accelerometer data between Windows and Linux | expand |
On Mon, 3 Dec 2018 14:57:07 +0800 Daniel Drake <drake@endlessm.com> wrote: > Jonathan Cameron wrote: > > If we want to support their ONT we'll need to do this first, then > > apply ONT on top of that by forming the relevant mount matrix and > > outputting that to userspace. > > If you fancy having a go it would be good to have this support! > > Cool, I didn't realise that there was a way to export mount matrices. > It looks like iio-sensor-proxy doesn't read that attribute yet, I will > submit a patch for that. > > For the kernel changes, here is my initial attempt, comments welcome. > I had to drop the const typing from iio_mount_matrix otherwise it's > difficult to dynamically construct it. > > Also I'm not sure whether we should apply this "default_ont" like Windows > does even when _ONT is not present? > > I would also love to hear from ST about how this situation happened and > if this is the right way forward. > > Regarding other devices with _ONT, the only other device we found > is Asus P4540UQ, a system that we worked on 2 years ago and no longer > have access to. I don't think we tested the accelerometer. The ACPI data > indicates SMO8820, with Y and Z axis values requiring sign flip. > > Thanks > Daniel Code looks good to me. Hopefully we'll get some info on where this came from and whether there is any standardization around it at all! Jonathan > --- > drivers/iio/accel/st_accel_core.c | 161 +++++++++++++++++++++++++- > include/linux/iio/common/st_sensors.h | 1 + > include/linux/iio/iio.h | 2 +- > 3 files changed, 162 insertions(+), 2 deletions(-) > > diff --git a/drivers/iio/accel/st_accel_core.c b/drivers/iio/accel/st_accel_core.c > index 3e6fd5a8ac5b..3eb4e4b55596 100644 > --- a/drivers/iio/accel/st_accel_core.c > +++ b/drivers/iio/accel/st_accel_core.c > @@ -11,6 +11,7 @@ > #include <linux/kernel.h> > #include <linux/module.h> > #include <linux/slab.h> > +#include <linux/acpi.h> > #include <linux/errno.h> > #include <linux/types.h> > #include <linux/mutex.h> > @@ -917,12 +918,157 @@ static const struct iio_trigger_ops st_accel_trigger_ops = { > #define ST_ACCEL_TRIGGER_OPS NULL > #endif > > +static const struct iio_mount_matrix * > +get_mount_matrix(const struct iio_dev *indio_dev, > + const struct iio_chan_spec *chan) > +{ > + struct st_sensor_data *adata = iio_priv(indio_dev); > + > + return adata->mount_matrix; > +} > + > +static const struct iio_chan_spec_ext_info mount_matrix_ext_info[] = { > + IIO_MOUNT_MATRIX(IIO_SHARED_BY_ALL, get_mount_matrix), > + { }, > +}; > + > +/* Read ST-specific _ONT orientation data from ACPI and generate an > + * appropriate mount matrix. > + */ > +static int apply_acpi_orientation(struct iio_dev *indio_dev, > + struct iio_chan_spec *channels) > +{ > + struct st_sensor_data *adata = iio_priv(indio_dev); > + struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; > + struct acpi_device *adev; > + union acpi_object *ont; > + union acpi_object *elements; > + acpi_status status; > + int ret = -EINVAL; > + unsigned int val; > + int i, j; > + int final_ont[3][3] = { 0 }; > + > + /* For some reason, ST's _ONT translation does not apply directly > + * to the data read from the sensor. Another translation must be > + * performed first, as described by the matrix below. Perhaps > + * ST required this specific translation for the first product > + * where the device was mounted? > + */ > + const int default_ont[3][3] = { > + { 0, 1, 0 }, > + { -1, 0, 0 }, > + { 0, 0, -1 }, > + }; > + > + > + adev = ACPI_COMPANION(adata->dev); > + if (!adev) > + return 0; > + > + /* Read _ONT data, which should be a package of 6 integers. */ > + status = acpi_evaluate_object(adev->handle, "_ONT", NULL, &buffer); > + if (ACPI_FAILURE(status)) { > + ret = status; > + goto out; > + } > + > + ont = buffer.pointer; > + if (ont->type != ACPI_TYPE_PACKAGE || ont->package.count != 6) > + goto out; > + > + /* The first 3 integers provide axis order information. > + * e.g. 0 1 2 would indicate normal X,Y,Z ordering. > + * e.g. 1 0 2 indicates that data arrives in order Y,X,Z. > + */ > + elements = ont->package.elements; > + for (i = 0; i < 3; i++) { > + if (elements[i].type != ACPI_TYPE_INTEGER) > + goto out; > + > + val = elements[i].integer.value; > + if (val < 0 || val > 2) > + goto out; > + > + /* Avoiding full matrix multiplication, we simply reorder the > + * columns in the default_ont matrix according to the > + * ordering provided by _ONT. > + */ > + final_ont[0][i] = default_ont[0][val]; > + final_ont[1][i] = default_ont[1][val]; > + final_ont[2][i] = default_ont[2][val]; > + } > + > + /* The final 3 integers provide sign flip information. > + * 0 means no change, 1 means flip. > + * e.g. 0 0 1 means that Z data should be sign-flipped. > + * This is applied after the axis reordering from above. > + */ > + elements += 3; > + for (i = 0; i < 3; i++) { > + if (elements[i].type != ACPI_TYPE_INTEGER) > + goto out; > + > + val = elements[i].integer.value; > + if (val != 0 && val != 1) > + goto out; > + if (!val) > + continue; > + > + /* Flip the values in the indicated column */ > + final_ont[0][i] *= -1; > + final_ont[1][i] *= -1; > + final_ont[2][i] *= -1; > + } > + > + /* Convert our integer matrix to a string-based iio_mount_matrix */ > + adata->mount_matrix = devm_kmalloc(&indio_dev->dev, > + sizeof(*adata->mount_matrix), > + GFP_KERNEL); > + if (!adata->mount_matrix) > + goto out; > + > + for (i = 0; i < 3; i++) { > + for (j = 0; j < 3; j++) { > + int matrix_val = final_ont[i][j]; > + char *str_value; > + > + switch (matrix_val) { > + case -1: > + str_value = "-1"; > + break; > + case 0: > + str_value = "0"; > + break; > + case 1: > + str_value = "1"; > + break; > + default: > + goto out; > + } > + adata->mount_matrix->rotation[i * 3 + j] = str_value; > + } > + } > + > + /* Expose the mount matrix via ext_info */ > + for (i = 0; i < indio_dev->num_channels; i++) > + channels[i].ext_info = mount_matrix_ext_info; > + > + ret = 0; > + > +out: > + kfree(buffer.pointer); > + return ret; > +} > + > int st_accel_common_probe(struct iio_dev *indio_dev) > { > struct st_sensor_data *adata = iio_priv(indio_dev); > struct st_sensors_platform_data *pdata = > (struct st_sensors_platform_data *)adata->dev->platform_data; > int irq = adata->get_irq_data_ready(indio_dev); > + struct iio_chan_spec *channels; > + size_t channels_size; > int err; > > indio_dev->modes = INDIO_DIRECT_MODE; > @@ -941,9 +1087,22 @@ int st_accel_common_probe(struct iio_dev *indio_dev) > > adata->num_data_channels = ST_ACCEL_NUMBER_DATA_CHANNELS; > adata->multiread_bit = adata->sensor_settings->multi_read_bit; > - indio_dev->channels = adata->sensor_settings->ch; > indio_dev->num_channels = ST_SENSORS_NUMBER_ALL_CHANNELS; > > + channels_size = indio_dev->num_channels * sizeof(struct iio_chan_spec); > + channels = devm_kmemdup(&indio_dev->dev, > + adata->sensor_settings->ch, > + channels_size, GFP_KERNEL); > + if (!channels) { > + err = -ENOMEM; > + goto st_accel_power_off; > + } > + > + err = apply_acpi_orientation(indio_dev, channels); > + if (err < 0) > + goto st_accel_power_off; > + > + indio_dev->channels = channels; > adata->current_fullscale = (struct st_sensor_fullscale_avl *) > &adata->sensor_settings->fs.fs_avl[0]; > adata->odr = adata->sensor_settings->odr.odr_avl[0].hz; > diff --git a/include/linux/iio/common/st_sensors.h b/include/linux/iio/common/st_sensors.h > index f9bd6e8ab138..fe15694128ac 100644 > --- a/include/linux/iio/common/st_sensors.h > +++ b/include/linux/iio/common/st_sensors.h > @@ -260,6 +260,7 @@ struct st_sensor_settings { > struct st_sensor_data { > struct device *dev; > struct iio_trigger *trig; > + struct iio_mount_matrix *mount_matrix; > struct st_sensor_settings *sensor_settings; > struct st_sensor_fullscale_avl *current_fullscale; > struct regulator *vdd; > diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h > index a74cb177dc6f..d3094ffeb9da 100644 > --- a/include/linux/iio/iio.h > +++ b/include/linux/iio/iio.h > @@ -125,7 +125,7 @@ ssize_t iio_enum_write(struct iio_dev *indio_dev, > * main hardware > */ > struct iio_mount_matrix { > - const char *rotation[9]; > + char *rotation[9]; > }; > > ssize_t iio_show_mount_matrix(struct iio_dev *indio_dev, uintptr_t priv,
diff --git a/drivers/iio/accel/st_accel_core.c b/drivers/iio/accel/st_accel_core.c index 3e6fd5a8ac5b..3eb4e4b55596 100644 --- a/drivers/iio/accel/st_accel_core.c +++ b/drivers/iio/accel/st_accel_core.c @@ -11,6 +11,7 @@ #include <linux/kernel.h> #include <linux/module.h> #include <linux/slab.h> +#include <linux/acpi.h> #include <linux/errno.h> #include <linux/types.h> #include <linux/mutex.h> @@ -917,12 +918,157 @@ static const struct iio_trigger_ops st_accel_trigger_ops = { #define ST_ACCEL_TRIGGER_OPS NULL #endif +static const struct iio_mount_matrix * +get_mount_matrix(const struct iio_dev *indio_dev, + const struct iio_chan_spec *chan) +{ + struct st_sensor_data *adata = iio_priv(indio_dev); + + return adata->mount_matrix; +} + +static const struct iio_chan_spec_ext_info mount_matrix_ext_info[] = { + IIO_MOUNT_MATRIX(IIO_SHARED_BY_ALL, get_mount_matrix), + { }, +}; + +/* Read ST-specific _ONT orientation data from ACPI and generate an + * appropriate mount matrix. + */ +static int apply_acpi_orientation(struct iio_dev *indio_dev, + struct iio_chan_spec *channels) +{ + struct st_sensor_data *adata = iio_priv(indio_dev); + struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; + struct acpi_device *adev; + union acpi_object *ont; + union acpi_object *elements; + acpi_status status; + int ret = -EINVAL; + unsigned int val; + int i, j; + int final_ont[3][3] = { 0 }; + + /* For some reason, ST's _ONT translation does not apply directly + * to the data read from the sensor. Another translation must be + * performed first, as described by the matrix below. Perhaps + * ST required this specific translation for the first product + * where the device was mounted? + */ + const int default_ont[3][3] = { + { 0, 1, 0 }, + { -1, 0, 0 }, + { 0, 0, -1 }, + }; + + + adev = ACPI_COMPANION(adata->dev); + if (!adev) + return 0; + + /* Read _ONT data, which should be a package of 6 integers. */ + status = acpi_evaluate_object(adev->handle, "_ONT", NULL, &buffer); + if (ACPI_FAILURE(status)) { + ret = status; + goto out; + } + + ont = buffer.pointer; + if (ont->type != ACPI_TYPE_PACKAGE || ont->package.count != 6) + goto out; + + /* The first 3 integers provide axis order information. + * e.g. 0 1 2 would indicate normal X,Y,Z ordering. + * e.g. 1 0 2 indicates that data arrives in order Y,X,Z. + */ + elements = ont->package.elements; + for (i = 0; i < 3; i++) { + if (elements[i].type != ACPI_TYPE_INTEGER) + goto out; + + val = elements[i].integer.value; + if (val < 0 || val > 2) + goto out; + + /* Avoiding full matrix multiplication, we simply reorder the + * columns in the default_ont matrix according to the + * ordering provided by _ONT. + */ + final_ont[0][i] = default_ont[0][val]; + final_ont[1][i] = default_ont[1][val]; + final_ont[2][i] = default_ont[2][val]; + } + + /* The final 3 integers provide sign flip information. + * 0 means no change, 1 means flip. + * e.g. 0 0 1 means that Z data should be sign-flipped. + * This is applied after the axis reordering from above. + */ + elements += 3; + for (i = 0; i < 3; i++) { + if (elements[i].type != ACPI_TYPE_INTEGER) + goto out; + + val = elements[i].integer.value; + if (val != 0 && val != 1) + goto out; + if (!val) + continue; + + /* Flip the values in the indicated column */ + final_ont[0][i] *= -1; + final_ont[1][i] *= -1; + final_ont[2][i] *= -1; + } + + /* Convert our integer matrix to a string-based iio_mount_matrix */ + adata->mount_matrix = devm_kmalloc(&indio_dev->dev, + sizeof(*adata->mount_matrix), + GFP_KERNEL); + if (!adata->mount_matrix) + goto out; + + for (i = 0; i < 3; i++) { + for (j = 0; j < 3; j++) { + int matrix_val = final_ont[i][j]; + char *str_value; + + switch (matrix_val) { + case -1: + str_value = "-1"; + break; + case 0: + str_value = "0"; + break; + case 1: + str_value = "1"; + break; + default: + goto out; + } + adata->mount_matrix->rotation[i * 3 + j] = str_value; + } + } + + /* Expose the mount matrix via ext_info */ + for (i = 0; i < indio_dev->num_channels; i++) + channels[i].ext_info = mount_matrix_ext_info; + + ret = 0; + +out: + kfree(buffer.pointer); + return ret; +} + int st_accel_common_probe(struct iio_dev *indio_dev) { struct st_sensor_data *adata = iio_priv(indio_dev); struct st_sensors_platform_data *pdata = (struct st_sensors_platform_data *)adata->dev->platform_data; int irq = adata->get_irq_data_ready(indio_dev); + struct iio_chan_spec *channels; + size_t channels_size; int err; indio_dev->modes = INDIO_DIRECT_MODE; @@ -941,9 +1087,22 @@ int st_accel_common_probe(struct iio_dev *indio_dev) adata->num_data_channels = ST_ACCEL_NUMBER_DATA_CHANNELS; adata->multiread_bit = adata->sensor_settings->multi_read_bit; - indio_dev->channels = adata->sensor_settings->ch; indio_dev->num_channels = ST_SENSORS_NUMBER_ALL_CHANNELS; + channels_size = indio_dev->num_channels * sizeof(struct iio_chan_spec); + channels = devm_kmemdup(&indio_dev->dev, + adata->sensor_settings->ch, + channels_size, GFP_KERNEL); + if (!channels) { + err = -ENOMEM; + goto st_accel_power_off; + } + + err = apply_acpi_orientation(indio_dev, channels); + if (err < 0) + goto st_accel_power_off; + + indio_dev->channels = channels; adata->current_fullscale = (struct st_sensor_fullscale_avl *) &adata->sensor_settings->fs.fs_avl[0]; adata->odr = adata->sensor_settings->odr.odr_avl[0].hz; diff --git a/include/linux/iio/common/st_sensors.h b/include/linux/iio/common/st_sensors.h index f9bd6e8ab138..fe15694128ac 100644 --- a/include/linux/iio/common/st_sensors.h +++ b/include/linux/iio/common/st_sensors.h @@ -260,6 +260,7 @@ struct st_sensor_settings { struct st_sensor_data { struct device *dev; struct iio_trigger *trig; + struct iio_mount_matrix *mount_matrix; struct st_sensor_settings *sensor_settings; struct st_sensor_fullscale_avl *current_fullscale; struct regulator *vdd; diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h index a74cb177dc6f..d3094ffeb9da 100644 --- a/include/linux/iio/iio.h +++ b/include/linux/iio/iio.h @@ -125,7 +125,7 @@ ssize_t iio_enum_write(struct iio_dev *indio_dev, * main hardware */ struct iio_mount_matrix { - const char *rotation[9]; + char *rotation[9]; }; ssize_t iio_show_mount_matrix(struct iio_dev *indio_dev, uintptr_t priv,