staging: iio: gyro: new driver for ADIS16251 devices

Signed-off-by: Barry Song <barry.song@analog.com>
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/iio/gyro/Kconfig

@@ -14,3 +14,13 @@ config ADIS16260
 
 	  This driver can also be built as a module.  If so, the module
 	  will be called adis16260.
+
+config ADIS16251
+	tristate "Analog Devices ADIS16251 Digital Gyroscope Sensor SPI driver"
+	depends on SPI
+	help
+	  Say yes here to build support for Analog Devices adis16261 programmable
+	  digital gyroscope sensor.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called adis16251.

drivers/staging/iio/gyro/Makefile

@@ -5,3 +5,6 @@
 adis16260-y             := adis16260_core.o
 adis16260-$(CONFIG_IIO_RING_BUFFER) += adis16260_ring.o adis16260_trigger.o
 obj-$(CONFIG_ADIS16260) += adis16260.o
+
+adis16251-y             := adis16251_core.o
+obj-$(CONFIG_ADIS16251) += adis16251.o

drivers/staging/iio/gyro/adis16251.h

+#ifndef SPI_ADIS16251_H_
+#define SPI_ADIS16251_H_
+
+#define ADIS16251_STARTUP_DELAY	220 /* ms */
+
+#define ADIS16251_READ_REG(a)    a
+#define ADIS16251_WRITE_REG(a) ((a) | 0x80)
+
+#define ADIS16251_ENDURANCE  0x00 /* Flash memory write count */
+#define ADIS16251_SUPPLY_OUT 0x02 /* Power supply measurement */
+#define ADIS16251_GYRO_OUT   0x04 /* X-axis gyroscope output */
+#define ADIS16251_AUX_ADC    0x0A /* analog input channel measurement */
+#define ADIS16251_TEMP_OUT   0x0C /* internal temperature measurement */
+#define ADIS16251_ANGL_OUT   0x0E /* angle displacement */
+#define ADIS16251_GYRO_OFF   0x14 /* Calibration, offset/bias adjustment */
+#define ADIS16251_GYRO_SCALE 0x16 /* Calibration, scale adjustment */
+#define ADIS16251_ALM_MAG1   0x20 /* Alarm 1 magnitude/polarity setting */
+#define ADIS16251_ALM_MAG2   0x22 /* Alarm 2 magnitude/polarity setting */
+#define ADIS16251_ALM_SMPL1  0x24 /* Alarm 1 dynamic rate of change setting */
+#define ADIS16251_ALM_SMPL2  0x26 /* Alarm 2 dynamic rate of change setting */
+#define ADIS16251_ALM_CTRL   0x28 /* Alarm control */
+#define ADIS16251_AUX_DAC    0x30 /* Auxiliary DAC data */
+#define ADIS16251_GPIO_CTRL  0x32 /* Control, digital I/O line */
+#define ADIS16251_MSC_CTRL   0x34 /* Control, data ready, self-test settings */
+#define ADIS16251_SMPL_PRD   0x36 /* Control, internal sample rate */
+#define ADIS16251_SENS_AVG   0x38 /* Control, dynamic range, filtering */
+#define ADIS16251_SLP_CNT    0x3A /* Control, sleep mode initiation */
+#define ADIS16251_DIAG_STAT  0x3C /* Diagnostic, error flags */
+#define ADIS16251_GLOB_CMD   0x3E /* Control, global commands */
+
+#define ADIS16251_ERROR_ACTIVE			(1<<14)
+#define ADIS16251_NEW_DATA			(1<<14)
+
+/* MSC_CTRL */
+#define ADIS16251_MSC_CTRL_INT_SELF_TEST	(1<<10) /* Internal self-test enable */
+#define ADIS16251_MSC_CTRL_NEG_SELF_TEST	(1<<9)
+#define ADIS16251_MSC_CTRL_POS_SELF_TEST	(1<<8)
+#define ADIS16251_MSC_CTRL_DATA_RDY_EN		(1<<2)
+#define ADIS16251_MSC_CTRL_DATA_RDY_POL_HIGH	(1<<1)
+#define ADIS16251_MSC_CTRL_DATA_RDY_DIO2	(1<<0)
+
+/* SMPL_PRD */
+#define ADIS16251_SMPL_PRD_TIME_BASE	(1<<7) /* Time base (tB): 0 = 1.953 ms, 1 = 60.54 ms */
+#define ADIS16251_SMPL_PRD_DIV_MASK	0x7F
+
+/* SLP_CNT */
+#define ADIS16251_SLP_CNT_POWER_OFF     0x80
+
+/* DIAG_STAT */
+#define ADIS16251_DIAG_STAT_ALARM2	(1<<9)
+#define ADIS16251_DIAG_STAT_ALARM1	(1<<8)
+#define ADIS16251_DIAG_STAT_SELF_TEST	(1<<5)
+#define ADIS16251_DIAG_STAT_OVERFLOW	(1<<4)
+#define ADIS16251_DIAG_STAT_SPI_FAIL	(1<<3)
+#define ADIS16251_DIAG_STAT_FLASH_UPT	(1<<2)
+#define ADIS16251_DIAG_STAT_POWER_HIGH	(1<<1)
+#define ADIS16251_DIAG_STAT_POWER_LOW	(1<<0)
+
+#define ADIS16251_DIAG_STAT_ERR_MASK (ADIS16261_DIAG_STAT_ALARM2 | \
+				      ADIS16261_DIAG_STAT_ALARM1 | \
+				      ADIS16261_DIAG_STAT_SELF_TEST | \
+				      ADIS16261_DIAG_STAT_OVERFLOW | \
+				      ADIS16261_DIAG_STAT_SPI_FAIL | \
+				      ADIS16261_DIAG_STAT_FLASH_UPT | \
+				      ADIS16261_DIAG_STAT_POWER_HIGH | \
+				      ADIS16261_DIAG_STAT_POWER_LOW)
+
+/* GLOB_CMD */
+#define ADIS16251_GLOB_CMD_SW_RESET	(1<<7)
+#define ADIS16251_GLOB_CMD_FLASH_UPD	(1<<3)
+#define ADIS16251_GLOB_CMD_DAC_LATCH	(1<<2)
+#define ADIS16251_GLOB_CMD_FAC_CALIB	(1<<1)
+#define ADIS16251_GLOB_CMD_AUTO_NULL	(1<<0)
+
+#define ADIS16251_MAX_TX 24
+#define ADIS16251_MAX_RX 24
+
+#define ADIS16251_SPI_SLOW	(u32)(300 * 1000)
+#define ADIS16251_SPI_BURST	(u32)(1000 * 1000)
+#define ADIS16251_SPI_FAST	(u32)(2000 * 1000)
+
+/**
+ * struct adis16251_state - device instance specific data
+ * @us:			actual spi_device
+ * @work_trigger_to_ring: bh for triggered event handling
+ * @inter:		used to check if new interrupt has been triggered
+ * @last_timestamp:	passing timestamp from th to bh of interrupt handler
+ * @indio_dev:		industrial I/O device structure
+ * @trig:		data ready trigger registered with iio
+ * @tx:			transmit buffer
+ * @rx:			recieve buffer
+ * @buf_lock:		mutex to protect tx and rx
+ **/
+struct adis16251_state {
+	struct spi_device		*us;
+	struct work_struct		work_trigger_to_ring;
+	s64				last_timestamp;
+	struct iio_dev			*indio_dev;
+	struct iio_trigger		*trig;
+	u8				*tx;
+	u8				*rx;
+	struct mutex			buf_lock;
+};
+
+int adis16251_spi_write_reg_8(struct device *dev,
+			      u8 reg_address,
+			      u8 val);
+
+int adis16251_spi_read_burst(struct device *dev, u8 *rx);
+
+int adis16251_spi_read_sequence(struct device *dev,
+				      u8 *tx, u8 *rx, int num);
+
+int adis16251_set_irq(struct device *dev, bool enable);
+
+int adis16251_reset(struct device *dev);
+
+int adis16251_stop_device(struct device *dev);
+
+int adis16251_check_status(struct device *dev);
+
+#if defined(CONFIG_IIO_RING_BUFFER) && defined(THIS_HAS_RING_BUFFER_SUPPORT)
+/* At the moment triggers are only used for ring buffer
+ * filling. This may change!
+ */
+
+enum adis16251_scan {
+	ADIS16251_SCAN_SUPPLY,
+	ADIS16251_SCAN_GYRO,
+	ADIS16251_SCAN_TEMP,
+	ADIS16251_SCAN_ADC_0,
+};
+
+void adis16251_remove_trigger(struct iio_dev *indio_dev);
+int adis16251_probe_trigger(struct iio_dev *indio_dev);
+
+ssize_t adis16251_read_data_from_ring(struct device *dev,
+				      struct device_attribute *attr,
+				      char *buf);
+
+
+int adis16251_configure_ring(struct iio_dev *indio_dev);
+void adis16251_unconfigure_ring(struct iio_dev *indio_dev);
+
+int adis16251_initialize_ring(struct iio_ring_buffer *ring);
+void adis16251_uninitialize_ring(struct iio_ring_buffer *ring);
+#else /* CONFIG_IIO_RING_BUFFER */
+
+static inline void adis16251_remove_trigger(struct iio_dev *indio_dev)
+{
+}
+
+static inline int adis16251_probe_trigger(struct iio_dev *indio_dev)
+{
+	return 0;
+}
+
+static inline ssize_t
+adis16251_read_data_from_ring(struct device *dev,
+			      struct device_attribute *attr,
+			      char *buf)
+{
+	return 0;
+}
+
+static int adis16251_configure_ring(struct iio_dev *indio_dev)
+{
+	return 0;
+}
+
+static inline void adis16251_unconfigure_ring(struct iio_dev *indio_dev)
+{
+}
+
+static inline int adis16251_initialize_ring(struct iio_ring_buffer *ring)
+{
+	return 0;
+}
+
+static inline void adis16251_uninitialize_ring(struct iio_ring_buffer *ring)
+{
+}
+
+#endif /* CONFIG_IIO_RING_BUFFER */
+#endif /* SPI_ADIS16251_H_ */

drivers/staging/iio/sysfs.h

@@ -107,6 +107,12 @@ struct iio_const_attr {
 #define IIO_DEV_ATTR_NAME(_show)				\
 	IIO_DEVICE_ATTR(name, S_IRUGO, _show, NULL, 0)
 
+/**
+ * IIO_DEV_ATTR_RESET: resets the device
+ **/
+#define IIO_DEV_ATTR_RESET(_store)			\
+	IIO_DEVICE_ATTR(reset, S_IWUGO, NULL, _store, 0)
+
 /**
  * IIO_CONST_ATTR_NAME - constant identifier
  * @_string: the name