iio:common: Add STMicroelectronics common library

This patch add a generic library for STMicroelectronics 3-axis sensors.

Signed-off-by: Denis Ciocca <denis.ciocca@st.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

1 files changed, 460 insertions, 0 deletions

diff --git a/drivers/iio/common/st_sensors/st_sensors_core.c b/drivers/iio/common/st_sensors/st_sensors_core.c
new file mode 100644
index 00000000000..fba6d6847b6
--- /dev/null
+++ b/drivers/iio/common/st_sensors/st_sensors_core.c
@@ -0,0 +1,460 @@
+/*
+ * STMicroelectronics sensors core library driver
+ *
+ * Copyright 2012-2013 STMicroelectronics Inc.
+ *
+ * Denis Ciocca <denis.ciocca@st.com>
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/iio/iio.h>
+#include <asm/unaligned.h>
+
+#include <linux/iio/common/st_sensors.h>
+
+
+#define ST_SENSORS_WAI_ADDRESS		0x0f
+
+static int st_sensors_write_data_with_mask(struct iio_dev *indio_dev,
+						u8 reg_addr, u8 mask, u8 data)
+{
+	int err;
+	u8 new_data;
+	struct st_sensor_data *sdata = iio_priv(indio_dev);
+
+	err = sdata->tf->read_byte(&sdata->tb, sdata->dev, reg_addr, &new_data);
+	if (err < 0)
+		goto st_sensors_write_data_with_mask_error;
+
+	new_data = ((new_data & (~mask)) | ((data << __ffs(mask)) & mask));
+	err = sdata->tf->write_byte(&sdata->tb, sdata->dev, reg_addr, new_data);
+
+st_sensors_write_data_with_mask_error:
+	return err;
+}
+
+int st_sensors_get_sampling_frequency_avl(struct iio_dev *indio_dev, char *buf)
+{
+	int i, len = 0;
+	struct st_sensor_data *sdata = iio_priv(indio_dev);
+
+	mutex_lock(&indio_dev->mlock);
+	for (i = 0; i < ST_SENSORS_ODR_LIST_MAX; i++) {
+		if (sdata->sensor->odr.odr_avl[i].hz == 0)
+			break;
+
+		len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
+					sdata->sensor->odr.odr_avl[i].hz);
+	}
+	mutex_unlock(&indio_dev->mlock);
+	buf[len - 1] = '\n';
+
+	return len;
+}
+EXPORT_SYMBOL(st_sensors_get_sampling_frequency_avl);
+
+int st_sensors_get_scale_avl(struct iio_dev *indio_dev, char *buf)
+{
+	int i, len = 0;
+	struct st_sensor_data *sdata = iio_priv(indio_dev);
+
+	mutex_lock(&indio_dev->mlock);
+	for (i = 0; i < ST_SENSORS_FULLSCALE_AVL_MAX; i++) {
+		if (sdata->sensor->fs.fs_avl[i].num == 0)
+			break;
+
+		len += scnprintf(buf + len, PAGE_SIZE - len, "0.%06u ",
+					sdata->sensor->fs.fs_avl[i].gain);
+	}
+	mutex_unlock(&indio_dev->mlock);
+	buf[len - 1] = '\n';
+
+	return len;
+}
+EXPORT_SYMBOL(st_sensors_get_scale_avl);
+
+static int st_sensors_match_odr(struct st_sensors *sensor,
+			unsigned int odr, struct st_sensor_odr_avl *odr_out)
+{
+	int i, ret = -EINVAL;
+
+	for (i = 0; i < ST_SENSORS_ODR_LIST_MAX; i++) {
+		if (sensor->odr.odr_avl[i].hz == 0)
+			goto st_sensors_match_odr_error;
+
+		if (sensor->odr.odr_avl[i].hz == odr) {
+			odr_out->hz = sensor->odr.odr_avl[i].hz;
+			odr_out->value = sensor->odr.odr_avl[i].value;
+			ret = 0;
+			break;
+		}
+	}
+
+st_sensors_match_odr_error:
+	return ret;
+}
+
+int st_sensors_set_odr(struct iio_dev *indio_dev, unsigned int odr)
+{
+	int err;
+	struct st_sensor_odr_avl odr_out;
+	struct st_sensor_data *sdata = iio_priv(indio_dev);
+
+	err = st_sensors_match_odr(sdata->sensor, odr, &odr_out);
+	if (err < 0)
+		goto st_sensors_match_odr_error;
+
+	if ((sdata->sensor->odr.addr == sdata->sensor->pw.addr) &&
+			(sdata->sensor->odr.mask == sdata->sensor->pw.mask)) {
+		if (sdata->enabled == true) {
+			err = st_sensors_write_data_with_mask(indio_dev,
+				sdata->sensor->odr.addr,
+				sdata->sensor->odr.mask,
+				odr_out.value);
+		} else {
+			err = 0;
+		}
+	} else {
+		err = st_sensors_write_data_with_mask(indio_dev,
+			sdata->sensor->odr.addr, sdata->sensor->odr.mask,
+			odr_out.value);
+	}
+	if (err >= 0)
+		sdata->odr = odr_out.hz;
+
+st_sensors_match_odr_error:
+	return err;
+}
+EXPORT_SYMBOL(st_sensors_set_odr);
+
+static int st_sensors_match_fs(struct st_sensors *sensor,
+					unsigned int fs, int *index_fs_avl)
+{
+	int i, ret = -EINVAL;
+
+	for (i = 0; i < ST_SENSORS_FULLSCALE_AVL_MAX; i++) {
+		if (sensor->fs.fs_avl[i].num == 0)
+			goto st_sensors_match_odr_error;
+
+		if (sensor->fs.fs_avl[i].num == fs) {
+			*index_fs_avl = i;
+			ret = 0;
+			break;
+		}
+	}
+
+st_sensors_match_odr_error:
+	return ret;
+}
+
+static int st_sensors_set_fullscale(struct iio_dev *indio_dev, unsigned int fs)
+{
+	int err, i;
+	struct st_sensor_data *sdata = iio_priv(indio_dev);
+
+	err = st_sensors_match_fs(sdata->sensor, fs, &i);
+	if (err < 0)
+		goto st_accel_set_fullscale_error;
+
+	err = st_sensors_write_data_with_mask(indio_dev,
+				sdata->sensor->fs.addr,
+				sdata->sensor->fs.mask,
+				sdata->sensor->fs.fs_avl[i].value);
+	if (err < 0)
+		goto st_accel_set_fullscale_error;
+
+	sdata->current_fullscale = (struct st_sensor_fullscale_avl *)
+						&sdata->sensor->fs.fs_avl[i];
+	return err;
+
+st_accel_set_fullscale_error:
+	dev_err(&indio_dev->dev, "failed to set new fullscale.\n");
+	return err;
+}
+
+int st_sensors_set_enable(struct iio_dev *indio_dev, bool enable)
+{
+	bool found;
+	u8 tmp_value;
+	int err = -EINVAL;
+	struct st_sensor_odr_avl odr_out;
+	struct st_sensor_data *sdata = iio_priv(indio_dev);
+
+	if (enable) {
+		found = false;
+		tmp_value = sdata->sensor->pw.value_on;
+		if ((sdata->sensor->odr.addr == sdata->sensor->pw.addr) &&
+			(sdata->sensor->odr.mask == sdata->sensor->pw.mask)) {
+			err = st_sensors_match_odr(sdata->sensor,
+							sdata->odr, &odr_out);
+			if (err < 0)
+				goto set_enable_error;
+			tmp_value = odr_out.value;
+			found = true;
+		}
+		err = st_sensors_write_data_with_mask(indio_dev,
+				sdata->sensor->pw.addr,
+				sdata->sensor->pw.mask, tmp_value);
+		if (err < 0)
+			goto set_enable_error;
+
+		sdata->enabled = true;
+
+		if (found)
+			sdata->odr = odr_out.hz;
+	} else {
+		err = st_sensors_write_data_with_mask(indio_dev,
+				sdata->sensor->pw.addr,
+				sdata->sensor->pw.mask,
+				sdata->sensor->pw.value_off);
+		if (err < 0)
+			goto set_enable_error;
+
+		sdata->enabled = false;
+	}
+
+set_enable_error:
+	return err;
+}
+EXPORT_SYMBOL(st_sensors_set_enable);
+
+int st_sensors_set_axis_enable(struct iio_dev *indio_dev, u8 axis_enable)
+{
+	struct st_sensor_data *sdata = iio_priv(indio_dev);
+
+	return st_sensors_write_data_with_mask(indio_dev,
+				sdata->sensor->enable_axis.addr,
+				sdata->sensor->enable_axis.mask, axis_enable);
+}
+EXPORT_SYMBOL(st_sensors_set_axis_enable);
+
+int st_sensors_init_sensor(struct iio_dev *indio_dev)
+{
+	int err;
+	struct st_sensor_data *sdata = iio_priv(indio_dev);
+
+	mutex_init(&sdata->tb.buf_lock);
+
+	err = st_sensors_set_enable(indio_dev, false);
+	if (err < 0)
+		goto init_error;
+
+	err = st_sensors_set_fullscale(indio_dev,
+						sdata->current_fullscale->num);
+	if (err < 0)
+		goto init_error;
+
+	err = st_sensors_set_odr(indio_dev, sdata->odr);
+	if (err < 0)
+		goto init_error;
+
+	/* set BDU */
+	err = st_sensors_write_data_with_mask(indio_dev,
+			sdata->sensor->bdu.addr, sdata->sensor->bdu.mask, true);
+	if (err < 0)
+		goto init_error;
+
+	err = st_sensors_set_axis_enable(indio_dev, ST_SENSORS_ENABLE_ALL_AXIS);
+
+init_error:
+	return err;
+}
+EXPORT_SYMBOL(st_sensors_init_sensor);
+
+int st_sensors_set_dataready_irq(struct iio_dev *indio_dev, bool enable)
+{
+	int err;
+	struct st_sensor_data *sdata = iio_priv(indio_dev);
+
+	/* Enable/Disable the interrupt generator 1. */
+	if (sdata->sensor->drdy_irq.ig1.en_addr > 0) {
+		err = st_sensors_write_data_with_mask(indio_dev,
+			sdata->sensor->drdy_irq.ig1.en_addr,
+			sdata->sensor->drdy_irq.ig1.en_mask, (int)enable);
+		if (err < 0)
+			goto st_accel_set_dataready_irq_error;
+	}
+
+	/* Enable/Disable the interrupt generator for data ready. */
+	err = st_sensors_write_data_with_mask(indio_dev,
+			sdata->sensor->drdy_irq.addr,
+			sdata->sensor->drdy_irq.mask, (int)enable);
+
+st_accel_set_dataready_irq_error:
+	return err;
+}
+EXPORT_SYMBOL(st_sensors_set_dataready_irq);
+
+int st_sensors_set_fullscale_by_gain(struct iio_dev *indio_dev, int scale)
+{
+	int err = -EINVAL, i;
+	struct st_sensor_data *sdata = iio_priv(indio_dev);
+
+	for (i = 0; i < ST_SENSORS_FULLSCALE_AVL_MAX; i++) {
+		if ((sdata->sensor->fs.fs_avl[i].gain == scale) &&
+				(sdata->sensor->fs.fs_avl[i].gain != 0)) {
+			err = 0;
+			break;
+		}
+	}
+	if (err < 0)
+		goto st_sensors_match_scale_error;
+
+	err = st_sensors_set_fullscale(indio_dev,
+					sdata->sensor->fs.fs_avl[i].num);
+
+st_sensors_match_scale_error:
+	return err;
+}
+EXPORT_SYMBOL(st_sensors_set_fullscale_by_gain);
+
+static int st_sensors_read_axis_data(struct iio_dev *indio_dev,
+							u8 ch_addr, int *data)
+{
+	int err;
+	u8 outdata[ST_SENSORS_BYTE_FOR_CHANNEL];
+	struct st_sensor_data *sdata = iio_priv(indio_dev);
+
+	err = sdata->tf->read_multiple_byte(&sdata->tb, sdata->dev,
+				ch_addr, ST_SENSORS_BYTE_FOR_CHANNEL,
+				outdata, sdata->multiread_bit);
+	if (err < 0)
+		goto read_error;
+
+	*data = (s16)get_unaligned_le16(outdata);
+
+read_error:
+	return err;
+}
+
+int st_sensors_read_info_raw(struct iio_dev *indio_dev,
+				struct iio_chan_spec const *ch, int *val)
+{
+	int err;
+	struct st_sensor_data *sdata = iio_priv(indio_dev);
+
+	mutex_lock(&indio_dev->mlock);
+	if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED) {
+		err = -EBUSY;
+		goto read_error;
+	} else {
+		err = st_sensors_set_enable(indio_dev, true);
+		if (err < 0)
+			goto read_error;
+
+		msleep((sdata->sensor->bootime * 1000) / sdata->odr);
+		err = st_sensors_read_axis_data(indio_dev, ch->address, val);
+		if (err < 0)
+			goto read_error;
+
+		*val = *val >> ch->scan_type.shift;
+	}
+	mutex_unlock(&indio_dev->mlock);
+
+	return err;
+
+read_error:
+	mutex_unlock(&indio_dev->mlock);
+	return err;
+}
+EXPORT_SYMBOL(st_sensors_read_info_raw);
+
+int st_sensors_check_device_support(struct iio_dev *indio_dev,
+			int num_sensors_list, const struct st_sensors *sensors)
+{
+	u8 wai;
+	int i, n, err;
+	struct st_sensor_data *sdata = iio_priv(indio_dev);
+
+	err = sdata->tf->read_byte(&sdata->tb, sdata->dev,
+					ST_SENSORS_DEFAULT_WAI_ADDRESS, &wai);
+	if (err < 0) {
+		dev_err(&indio_dev->dev, "failed to read Who-Am-I register.\n");
+		goto read_wai_error;
+	}
+
+	for (i = 0; i < num_sensors_list; i++) {
+		if (sensors[i].wai == wai)
+			break;
+	}
+	if (i == num_sensors_list)
+		goto device_not_supported;
+
+	for (n = 0; n < ARRAY_SIZE(sensors[i].sensors_supported); n++) {
+		if (strcmp(indio_dev->name,
+				&sensors[i].sensors_supported[n][0]) == 0)
+			break;
+	}
+	if (n == ARRAY_SIZE(sensors[i].sensors_supported)) {
+		dev_err(&indio_dev->dev, "device name and WhoAmI mismatch.\n");
+		goto sensor_name_mismatch;
+	}
+
+	sdata->sensor = (struct st_sensors *)&sensors[i];
+
+	return i;
+
+device_not_supported:
+	dev_err(&indio_dev->dev, "device not supported: WhoAmI (0x%x).\n", wai);
+sensor_name_mismatch:
+	err = -ENODEV;
+read_wai_error:
+	return err;
+}
+EXPORT_SYMBOL(st_sensors_check_device_support);
+
+ssize_t st_sensors_sysfs_get_sampling_frequency(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct st_sensor_data *adata = iio_priv(dev_get_drvdata(dev));
+
+	return sprintf(buf, "%d\n", adata->odr);
+}
+EXPORT_SYMBOL(st_sensors_sysfs_get_sampling_frequency);
+
+ssize_t st_sensors_sysfs_set_sampling_frequency(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t size)
+{
+	int err;
+	unsigned int odr;
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+
+	err = kstrtoint(buf, 10, &odr);
+	if (err < 0)
+		goto conversion_error;
+
+	mutex_lock(&indio_dev->mlock);
+	err = st_sensors_set_odr(indio_dev, odr);
+	mutex_unlock(&indio_dev->mlock);
+
+conversion_error:
+	return err < 0 ? err : size;
+}
+EXPORT_SYMBOL(st_sensors_sysfs_set_sampling_frequency);
+
+ssize_t st_sensors_sysfs_sampling_frequency_avail(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+
+	return st_sensors_get_sampling_frequency_avl(indio_dev, buf);
+}
+EXPORT_SYMBOL(st_sensors_sysfs_sampling_frequency_avail);
+
+ssize_t st_sensors_sysfs_scale_avail(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+
+	return st_sensors_get_scale_avl(indio_dev, buf);
+}
+EXPORT_SYMBOL(st_sensors_sysfs_scale_avail);
+
+MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics ST-sensors core");
+MODULE_LICENSE("GPL v2");