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>

3 files changed, 314 insertions, 0 deletions

diff --git a/include/linux/iio/common/st_sensors.h b/include/linux/iio/common/st_sensors.h
new file mode 100644
index 000000000000..3cc85715491f
--- /dev/null
+++ b/include/linux/iio/common/st_sensors.h
@@ -0,0 +1,274 @@
+/*
+ * STMicroelectronics sensors library driver
+ *
+ * Copyright 2012-2013 STMicroelectronics Inc.
+ *
+ * Denis Ciocca <denis.ciocca@st.com>
+ *
+ * Licensed under the GPL-2.
+ */
+
+#ifndef ST_SENSORS_H
+#define ST_SENSORS_H
+
+#include <linux/i2c.h>
+#include <linux/spi/spi.h>
+#include <linux/irqreturn.h>
+#include <linux/iio/trigger.h>
+
+#define ST_SENSORS_TX_MAX_LENGTH		2
+#define ST_SENSORS_RX_MAX_LENGTH		6
+
+#define ST_SENSORS_ODR_LIST_MAX			10
+#define ST_SENSORS_FULLSCALE_AVL_MAX		10
+
+#define ST_SENSORS_NUMBER_ALL_CHANNELS		4
+#define ST_SENSORS_NUMBER_DATA_CHANNELS		3
+#define ST_SENSORS_ENABLE_ALL_AXIS		0x07
+#define ST_SENSORS_BYTE_FOR_CHANNEL		2
+#define ST_SENSORS_SCAN_X			0
+#define ST_SENSORS_SCAN_Y			1
+#define ST_SENSORS_SCAN_Z			2
+#define ST_SENSORS_DEFAULT_12_REALBITS		12
+#define ST_SENSORS_DEFAULT_16_REALBITS		16
+#define ST_SENSORS_DEFAULT_POWER_ON_VALUE	0x01
+#define ST_SENSORS_DEFAULT_POWER_OFF_VALUE	0x00
+#define ST_SENSORS_DEFAULT_WAI_ADDRESS		0x0f
+#define ST_SENSORS_DEFAULT_AXIS_ADDR		0x20
+#define ST_SENSORS_DEFAULT_AXIS_MASK		0x07
+#define ST_SENSORS_DEFAULT_AXIS_N_BIT		3
+
+#define ST_SENSORS_MAX_NAME			17
+#define ST_SENSORS_MAX_4WAI			7
+
+#define ST_SENSORS_LSM_CHANNELS(device_type, index, mod, endian, bits, addr) \
+{ \
+	.type = device_type, \
+	.modified = 1, \
+	.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | \
+			IIO_CHAN_INFO_SCALE_SEPARATE_BIT, \
+	.scan_index = index, \
+	.channel2 = mod, \
+	.address = addr, \
+	.scan_type = { \
+		.sign = 's', \
+		.realbits = bits, \
+		.shift = 16 - bits, \
+		.storagebits = 16, \
+		.endianness = endian, \
+	}, \
+}
+
+#define ST_SENSOR_DEV_ATTR_SAMP_FREQ() \
+		IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO, \
+			st_sensors_sysfs_get_sampling_frequency, \
+			st_sensors_sysfs_set_sampling_frequency)
+
+#define ST_SENSORS_DEV_ATTR_SAMP_FREQ_AVAIL() \
+		IIO_DEV_ATTR_SAMP_FREQ_AVAIL( \
+			st_sensors_sysfs_sampling_frequency_avail)
+
+#define ST_SENSORS_DEV_ATTR_SCALE_AVAIL(name) \
+		IIO_DEVICE_ATTR(name, S_IRUGO, \
+			st_sensors_sysfs_scale_avail, NULL , 0);
+
+struct st_sensor_odr_avl {
+	unsigned int hz;
+	u8 value;
+};
+
+struct st_sensor_odr {
+	u8 addr;
+	u8 mask;
+	struct st_sensor_odr_avl odr_avl[ST_SENSORS_ODR_LIST_MAX];
+};
+
+struct st_sensor_power {
+	u8 addr;
+	u8 mask;
+	u8 value_off;
+	u8 value_on;
+};
+
+struct st_sensor_axis {
+	u8 addr;
+	u8 mask;
+};
+
+struct st_sensor_fullscale_avl {
+	unsigned int num;
+	u8 value;
+	unsigned int gain;
+	unsigned int gain2;
+};
+
+struct st_sensor_fullscale {
+	u8 addr;
+	u8 mask;
+	struct st_sensor_fullscale_avl fs_avl[ST_SENSORS_FULLSCALE_AVL_MAX];
+};
+
+/**
+ * struct st_sensor_bdu - ST sensor device block data update
+ * @addr: address of the register.
+ * @mask: mask to write the block data update flag.
+ */
+struct st_sensor_bdu {
+	u8 addr;
+	u8 mask;
+};
+
+/**
+ * struct st_sensor_data_ready_irq - ST sensor device data-ready interrupt
+ * @addr: address of the register.
+ * @mask: mask to write the on/off value.
+ * struct ig1 - represents the Interrupt Generator 1 of sensors.
+ * @en_addr: address of the enable ig1 register.
+ * @en_mask: mask to write the on/off value for enable.
+ */
+struct st_sensor_data_ready_irq {
+	u8 addr;
+	u8 mask;
+	struct {
+		u8 en_addr;
+		u8 en_mask;
+	} ig1;
+};
+
+/**
+ * struct st_sensor_transfer_buffer - ST sensor device I/O buffer
+ * @buf_lock: Mutex to protect rx and tx buffers.
+ * @tx_buf: Buffer used by SPI transfer function to send data to the sensors.
+ *	This buffer is used to avoid DMA not-aligned issue.
+ * @rx_buf: Buffer used by SPI transfer to receive data from sensors.
+ *	This buffer is used to avoid DMA not-aligned issue.
+ */
+struct st_sensor_transfer_buffer {
+	struct mutex buf_lock;
+	u8 rx_buf[ST_SENSORS_RX_MAX_LENGTH];
+	u8 tx_buf[ST_SENSORS_TX_MAX_LENGTH] ____cacheline_aligned;
+};
+
+/**
+ * struct st_sensor_transfer_function - ST sensor device I/O function
+ * @read_byte: Function used to read one byte.
+ * @write_byte: Function used to write one byte.
+ * @read_multiple_byte: Function used to read multiple byte.
+ */
+struct st_sensor_transfer_function {
+	int (*read_byte) (struct st_sensor_transfer_buffer *tb,
+				struct device *dev, u8 reg_addr, u8 *res_byte);
+	int (*write_byte) (struct st_sensor_transfer_buffer *tb,
+				struct device *dev, u8 reg_addr, u8 data);
+	int (*read_multiple_byte) (struct st_sensor_transfer_buffer *tb,
+		struct device *dev, u8 reg_addr, int len, u8 *data,
+							bool multiread_bit);
+};
+
+/**
+ * struct st_sensors - ST sensors list
+ * @wai: Contents of WhoAmI register.
+ * @sensors_supported: List of supported sensors by struct itself.
+ * @ch: IIO channels for the sensor.
+ * @odr: Output data rate register and ODR list available.
+ * @pw: Power register of the sensor.
+ * @enable_axis: Enable one or more axis of the sensor.
+ * @fs: Full scale register and full scale list available.
+ * @bdu: Block data update register.
+ * @drdy_irq: Data ready register of the sensor.
+ * @multi_read_bit: Use or not particular bit for [I2C/SPI] multi-read.
+ * @bootime: samples to discard when sensor passing from power-down to power-up.
+ */
+struct st_sensors {
+	u8 wai;
+	char sensors_supported[ST_SENSORS_MAX_4WAI][ST_SENSORS_MAX_NAME];
+	struct iio_chan_spec *ch;
+	struct st_sensor_odr odr;
+	struct st_sensor_power pw;
+	struct st_sensor_axis enable_axis;
+	struct st_sensor_fullscale fs;
+	struct st_sensor_bdu bdu;
+	struct st_sensor_data_ready_irq drdy_irq;
+	bool multi_read_bit;
+	unsigned int bootime;
+};
+
+/**
+ * struct st_sensor_data - ST sensor device status
+ * @dev: Pointer to instance of struct device (I2C or SPI).
+ * @trig: The trigger in use by the core driver.
+ * @sensor: Pointer to the current sensor struct in use.
+ * @current_fullscale: Maximum range of measure by the sensor.
+ * @enabled: Status of the sensor (false->off, true->on).
+ * @multiread_bit: Use or not particular bit for [I2C/SPI] multiread.
+ * @buffer_data: Data used by buffer part.
+ * @odr: Output data rate of the sensor [Hz].
+ * @get_irq_data_ready: Function to get the IRQ used for data ready signal.
+ * @tf: Transfer function structure used by I/O operations.
+ * @tb: Transfer buffers and mutex used by I/O operations.
+ */
+struct st_sensor_data {
+	struct device *dev;
+	struct iio_trigger *trig;
+	struct st_sensors *sensor;
+	struct st_sensor_fullscale_avl *current_fullscale;
+
+	bool enabled;
+	bool multiread_bit;
+
+	char *buffer_data;
+
+	unsigned int odr;
+
+	unsigned int (*get_irq_data_ready) (struct iio_dev *indio_dev);
+
+	const struct st_sensor_transfer_function *tf;
+	struct st_sensor_transfer_buffer tb;
+};
+
+#ifdef CONFIG_IIO_BUFFER
+int st_sensors_allocate_trigger(struct iio_dev *indio_dev,
+				const struct iio_trigger_ops *trigger_ops);
+
+void st_sensors_deallocate_trigger(struct iio_dev *indio_dev);
+
+irqreturn_t st_sensors_trigger_handler(int irq, void *p);
+
+int st_sensors_get_buffer_element(struct iio_dev *indio_dev, u8 *buf);
+#endif
+
+int st_sensors_init_sensor(struct iio_dev *indio_dev);
+
+int st_sensors_set_enable(struct iio_dev *indio_dev, bool enable);
+
+int st_sensors_set_axis_enable(struct iio_dev *indio_dev, u8 axis_enable);
+
+int st_sensors_get_sampling_frequency_avl(struct iio_dev *indio_dev, char *buf);
+
+int st_sensors_get_scale_avl(struct iio_dev *indio_dev, char *buf);
+
+int st_sensors_set_odr(struct iio_dev *indio_dev, unsigned int odr);
+
+int st_sensors_set_dataready_irq(struct iio_dev *indio_dev, bool enable);
+
+int st_sensors_set_fullscale_by_gain(struct iio_dev *indio_dev, int scale);
+
+int st_sensors_read_info_raw(struct iio_dev *indio_dev,
+				struct iio_chan_spec const *ch, int *val);
+
+int st_sensors_check_device_support(struct iio_dev *indio_dev,
+			int num_sensors_list, const struct st_sensors *sensors);
+
+ssize_t st_sensors_sysfs_get_sampling_frequency(struct device *dev,
+				struct device_attribute *attr, char *buf);
+
+ssize_t st_sensors_sysfs_set_sampling_frequency(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t size);
+
+ssize_t st_sensors_sysfs_sampling_frequency_avail(struct device *dev,
+				struct device_attribute *attr, char *buf);
+
+ssize_t st_sensors_sysfs_scale_avail(struct device *dev,
+				struct device_attribute *attr, char *buf);
+
+#endif /* ST_SENSORS_H */
diff --git a/include/linux/iio/common/st_sensors_i2c.h b/include/linux/iio/common/st_sensors_i2c.h
new file mode 100644
index 000000000000..67d845385ae2
--- /dev/null
+++ b/include/linux/iio/common/st_sensors_i2c.h
@@ -0,0 +1,20 @@
+/*
+ * STMicroelectronics sensors i2c library driver
+ *
+ * Copyright 2012-2013 STMicroelectronics Inc.
+ *
+ * Denis Ciocca <denis.ciocca@st.com>
+ *
+ * Licensed under the GPL-2.
+ */
+
+#ifndef ST_SENSORS_I2C_H
+#define ST_SENSORS_I2C_H
+
+#include <linux/i2c.h>
+#include <linux/iio/common/st_sensors.h>
+
+void st_sensors_i2c_configure(struct iio_dev *indio_dev,
+		struct i2c_client *client, struct st_sensor_data *sdata);
+
+#endif /* ST_SENSORS_I2C_H */
diff --git a/include/linux/iio/common/st_sensors_spi.h b/include/linux/iio/common/st_sensors_spi.h
new file mode 100644
index 000000000000..d964a3563dc6
--- /dev/null
+++ b/include/linux/iio/common/st_sensors_spi.h
@@ -0,0 +1,20 @@
+/*
+ * STMicroelectronics sensors spi library driver
+ *
+ * Copyright 2012-2013 STMicroelectronics Inc.
+ *
+ * Denis Ciocca <denis.ciocca@st.com>
+ *
+ * Licensed under the GPL-2.
+ */
+
+#ifndef ST_SENSORS_SPI_H
+#define ST_SENSORS_SPI_H
+
+#include <linux/spi/spi.h>
+#include <linux/iio/common/st_sensors.h>
+
+void st_sensors_spi_configure(struct iio_dev *indio_dev,
+			struct spi_device *spi, struct st_sensor_data *sdata);
+
+#endif /* ST_SENSORS_SPI_H */