Staging: IIO: VTI sca3000 series accelerometer driver (spi)
Example of how a device with a hardware ring buffer is handled within IIO. Changes since V2: * Moved to new registration functions giving much cleaner interface. Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>wifi-calibration
Jonathan Cameron
Greg Kroah-Hartman
parent
7026ea4b52
commit
574fb258d6
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@ -17,3 +17,11 @@ config LIS3L02DQ
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Say yes here to build SPI support for the ST microelectronics
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Say yes here to build SPI support for the ST microelectronics
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accelerometer. The driver supplies direct access via sysfs files
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accelerometer. The driver supplies direct access via sysfs files
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and an event interface via a character device.
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and an event interface via a character device.
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config SCA3000
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depends on IIO_RING_BUFFER
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depends on SPI
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tristate "VTI SCA3000 series accelerometers"
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help
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Say yes here to build support for the VTI SCA3000 series of SPI
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accelerometers. These devices use a hardware ring buffer.
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@ -5,3 +5,6 @@ obj-$(CONFIG_KXSD9) += kxsd9.o
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lis3l02dq-y := lis3l02dq_core.o
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lis3l02dq-y := lis3l02dq_core.o
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obj-$(CONFIG_LIS3L02DQ) += lis3l02dq.o
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obj-$(CONFIG_LIS3L02DQ) += lis3l02dq.o
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sca3000-y := sca3000_core.o sca3000_ring.o
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obj-$(CONFIG_SCA3000) += sca3000.o
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@ -0,0 +1,298 @@
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/*
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* sca3000.c -- support VTI sca3000 series accelerometers
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* via SPI
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*
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* Copyright (c) 2007 Jonathan Cameron <jic23@cam.ac.uk>
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*
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* Partly based upon tle62x0.c
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* Initial mode is direct measurement.
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*
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* Untested things
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*
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* Temperature reading (the e05 I'm testing with doesn't have a sensor)
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*
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* Free fall detection mode - supported but untested as I'm not droping my
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* dubious wire rig far enough to test it.
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*
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* Unsupported as yet
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*
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* Time stamping of data from ring. Various ideas on how to do this but none
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* are remotely simple. Suggestions welcome.
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*
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* Individual enabling disabling of channels going into ring buffer
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*
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* Overflow handling (this is signaled for all but 8 bit ring buffer mode.)
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*
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* Motion detector using AND combinations of signals.
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*
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* Note: Be very careful about not touching an register bytes marked
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* as reserved on the data sheet. They really mean it as changing convents of
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* some will cause the device to lock up.
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*
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* Known issues - on rare occasions the interrupts lock up. Not sure why as yet.
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* Can probably alleviate this by reading the interrupt register on start, but
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* that is really just brushing the problem under the carpet.
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*/
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#define SCA3000_WRITE_REG(a) (((a) << 2) | 0x02)
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#define SCA3000_READ_REG(a) ((a) << 2)
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#define SCA3000_REG_ADDR_REVID 0x00
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#define SCA3000_REVID_MAJOR_MASK 0xf0
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#define SCA3000_REVID_MINOR_MASK 0x0f
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#define SCA3000_REG_ADDR_STATUS 0x02
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#define SCA3000_LOCKED 0x20
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#define SCA3000_EEPROM_CS_ERROR 0x02
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#define SCA3000_SPI_FRAME_ERROR 0x01
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/* All reads done using register decrement so no need to directly access LSBs */
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#define SCA3000_REG_ADDR_X_MSB 0x05
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#define SCA3000_REG_ADDR_Y_MSB 0x07
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#define SCA3000_REG_ADDR_Z_MSB 0x09
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#define SCA3000_REG_ADDR_RING_OUT 0x0f
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/* Temp read untested - the e05 doesn't have the sensor */
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#define SCA3000_REG_ADDR_TEMP_MSB 0x13
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#define SCA3000_REG_ADDR_MODE 0x14
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#define SCA3000_MODE_PROT_MASK 0x28
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#define SCA3000_RING_BUF_ENABLE 0x80
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#define SCA3000_RING_BUF_8BIT 0x40
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/* Free fall detection triggers an interrupt if the acceleration
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* is below a threshold for equivalent of 25cm drop
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*/
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#define SCA3000_FREE_FALL_DETECT 0x10
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#define SCA3000_MEAS_MODE_NORMAL 0x00
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#define SCA3000_MEAS_MODE_OP_1 0x01
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#define SCA3000_MEAS_MODE_OP_2 0x02
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/* In motion detection mode the accelerations are band pass filtered
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* (aprox 1 - 25Hz) and then a programmable theshold used to trigger
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* and interrupt.
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*/
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#define SCA3000_MEAS_MODE_MOT_DET 0x03
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#define SCA3000_REG_ADDR_BUF_COUNT 0x15
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#define SCA3000_REG_ADDR_INT_STATUS 0x16
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#define SCA3000_INT_STATUS_THREE_QUARTERS 0x80
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#define SCA3000_INT_STATUS_HALF 0x40
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#define SCA3000_INT_STATUS_FREE_FALL 0x08
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#define SCA3000_INT_STATUS_Y_TRIGGER 0x04
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#define SCA3000_INT_STATUS_X_TRIGGER 0x02
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#define SCA3000_INT_STATUS_Z_TRIGGER 0x01
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/* Used to allow accesss to multiplexed registers */
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#define SCA3000_REG_ADDR_CTRL_SEL 0x18
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/* Only available for SCA3000-D03 and SCA3000-D01 */
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#define SCA3000_REG_CTRL_SEL_I2C_DISABLE 0x01
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#define SCA3000_REG_CTRL_SEL_MD_CTRL 0x02
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#define SCA3000_REG_CTRL_SEL_MD_Y_TH 0x03
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#define SCA3000_REG_CTRL_SEL_MD_X_TH 0x04
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#define SCA3000_REG_CTRL_SEL_MD_Z_TH 0x05
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/* BE VERY CAREFUL WITH THIS, IF 3 BITS ARE NOT SET the device
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will not function */
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#define SCA3000_REG_CTRL_SEL_OUT_CTRL 0x0B
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#define SCA3000_OUT_CTRL_PROT_MASK 0xE0
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#define SCA3000_OUT_CTRL_BUF_X_EN 0x10
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#define SCA3000_OUT_CTRL_BUF_Y_EN 0x08
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#define SCA3000_OUT_CTRL_BUF_Z_EN 0x04
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#define SCA3000_OUT_CTRL_BUF_DIV_4 0x02
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#define SCA3000_OUT_CTRL_BUF_DIV_2 0x01
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/* Control which motion detector interrupts are on.
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* For now only OR combinations are supported.x
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*/
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#define SCA3000_MD_CTRL_PROT_MASK 0xC0
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#define SCA3000_MD_CTRL_OR_Y 0x01
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#define SCA3000_MD_CTRL_OR_X 0x02
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#define SCA3000_MD_CTRL_OR_Z 0x04
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/* Currently unsupported */
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#define SCA3000_MD_CTRL_AND_Y 0x08
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#define SCA3000_MD_CTRL_AND_X 0x10
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#define SAC3000_MD_CTRL_AND_Z 0x20
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/* Some control registers of complex access methods requiring this register to
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* be used to remove a lock.
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*/
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#define SCA3000_REG_ADDR_UNLOCK 0x1e
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#define SCA3000_REG_ADDR_INT_MASK 0x21
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#define SCA3000_INT_MASK_PROT_MASK 0x1C
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#define SCA3000_INT_MASK_RING_THREE_QUARTER 0x80
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#define SCA3000_INT_MASK_RING_HALF 0x40
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#define SCA3000_INT_MASK_ALL_INTS 0x02
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#define SCA3000_INT_MASK_ACTIVE_HIGH 0x01
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#define SCA3000_INT_MASK_ACTIVE_LOW 0x00
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/* Values of mulipexed registers (write to ctrl_data after select) */
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#define SCA3000_REG_ADDR_CTRL_DATA 0x22
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/* Measurment modes available on some sca3000 series chips. Code assumes others
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* may become available in the future.
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*
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* Bypass - Bypass the low-pass filter in the signal channel so as to increase
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* signal bandwidth.
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*
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* Narrow - Narrow low-pass filtering of the signal channel and half output
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* data rate by decimation.
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*
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* Wide - Widen low-pass filtering of signal channel to increase bandwidth
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*/
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#define SCA3000_OP_MODE_BYPASS 0x01
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#define SCA3000_OP_MODE_NARROW 0x02
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#define SCA3000_OP_MODE_WIDE 0x04
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#define SCA3000_MAX_TX 6
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#define SCA3000_MAX_RX 2
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/**
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* struct sca3000_state - device instance state information
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* @us: the associated spi device
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* @info: chip variant information
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* @indio_dev: device information used by the IIO core
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* @interrupt_handler_ws: event interrupt handler for all events
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* @last_timestamp: the timestamp of the last event
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* @mo_det_use_count: reference counter for the motion detection unit
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* @lock: lock used to protect elements of sca3000_state
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* and the underlying device state.
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* @bpse: number of bits per scan element
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* @tx: dma-able transmit buffer
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* @rx: dma-able receive buffer
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**/
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struct sca3000_state {
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struct spi_device *us;
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const struct sca3000_chip_info *info;
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struct iio_dev *indio_dev;
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struct work_struct interrupt_handler_ws;
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s64 last_timestamp;
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int mo_det_use_count;
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struct mutex lock;
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int bpse;
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u8 *tx;
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/* not used during a ring buffer read */
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u8 *rx;
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};
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/**
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* struct sca3000_chip_info - model dependant parameters
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* @name: model identification
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* @temp_output: some devices have temperature sensors.
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* @measurement_mode_freq: normal mode sampling frequency
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* @option_mode_1: first optional mode. Not all models have one
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* @option_mode_1_freq: option mode 1 sampling frequency
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* @option_mode_2: second optional mode. Not all chips have one
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* @option_mode_2_freq: option mode 2 sampling frequency
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*
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* This structure is used to hold information about the functionality of a given
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* sca3000 variant.
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**/
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struct sca3000_chip_info {
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const char *name;
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bool temp_output;
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int measurement_mode_freq;
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int option_mode_1;
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int option_mode_1_freq;
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int option_mode_2;
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int option_mode_2_freq;
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};
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/**
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* sca3000_read_data() read a series of values from the device
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* @dev: device
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* @reg_address_high: start address (decremented read)
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* @rx: pointer where recieved data is placed. Callee
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* responsible for freeing this.
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* @len: number of bytes to read
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*
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* The main lock must be held.
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**/
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int sca3000_read_data(struct sca3000_state *st,
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u8 reg_address_high,
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u8 **rx_p,
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int len);
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/**
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* sca3000_write_reg() write a single register
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* @address: address of register on chip
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* @val: value to be written to register
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*
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* The main lock must be held.
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**/
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int sca3000_write_reg(struct sca3000_state *st, u8 address, u8 val);
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/* Conversion function for use with the ring buffer when in 11bit mode */
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static inline int sca3000_11bit_convert(uint8_t msb, uint8_t lsb)
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{
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int16_t val;
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val = ((lsb >> 3) & 0x1C) | (msb << 5);
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val |= (val & (1 << 12)) ? 0xE000 : 0;
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return val;
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};
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static inline int sca3000_13bit_convert(uint8_t msb, uint8_t lsb)
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{
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s16 val;
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val = ((lsb >> 3) & 0x1F) | (msb << 5);
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/* sign fill */
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val |= (val & (1 << 12)) ? 0xE000 : 0;
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return val;
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};
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#ifdef CONFIG_IIO_RING_BUFFER
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/**
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* sca3000_register_ring_funcs() setup the ring state change functions
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**/
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void sca3000_register_ring_funcs(struct iio_dev *indio_dev);
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/**
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* sca3000_configure_ring() - allocate and configure ring buffer
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* @indio_dev: iio-core device whose ring is to be configured
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*
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* The hardware ring buffer needs far fewer ring buffer functions than
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* a software one as a lot of things are handled automatically.
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* This function also tells the iio core that our device supports a
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* hardware ring buffer mode.
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**/
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int sca3000_configure_ring(struct iio_dev *indio_dev);
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/**
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* sca3000_unconfigure_ring() - deallocate the ring buffer
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* @indio_dev: iio-core device whose ring we are freeing
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**/
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void sca3000_unconfigure_ring(struct iio_dev *indio_dev);
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/**
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* sca3000_ring_int_process() handles ring related event pushing and escalation
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* @val: the event code
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**/
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void sca3000_ring_int_process(u8 val, struct iio_ring_buffer *ring);
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#else
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static inline void sca3000_register_ring_funcs(struct iio_dev *indio_dev) {};
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static inline
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int sca3000_register_ring_access_and_init(struct iio_dev *indio_dev)
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{
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return 0;
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};
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static inline void sca3000_ring_int_process(u8 val, void *ring) {};
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#endif
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File diff suppressed because it is too large
Load Diff
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@ -0,0 +1,331 @@
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/*
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* sca3000_ring.c -- support VTI sca3000 series accelerometers via SPI
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 as published by
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* the Free Software Foundation.
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*
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* Copyright (c) 2009 Jonathan Cameron <jic23@cam.ac.uk>
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*
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*/
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#include <linux/interrupt.h>
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#include <linux/gpio.h>
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#include <linux/fs.h>
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#include <linux/device.h>
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#include <linux/kernel.h>
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#include <linux/spi/spi.h>
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#include <linux/sysfs.h>
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#include "../iio.h"
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#include "../sysfs.h"
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#include "../ring_generic.h"
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#include "../ring_hw.h"
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#include "accel.h"
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#include "sca3000.h"
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/* RFC / future work
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*
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* The internal ring buffer doesn't actually change what it holds depending
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* on which signals are enabled etc, merely whether you can read them.
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* As such the scan mode selection is somewhat different than for a software
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* ring buffer and changing it actually covers any data already in the buffer.
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* Currently scan elements aren't configured so it doesn't matter.
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*/
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/**
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* sca3000_rip_hw_rb() - main ring access function, pulls data from ring
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* @r: the ring
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* @count: number of samples to try and pull
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||||||
|
* @data: output the actual samples pulled from the hw ring
|
||||||
|
* @dead_offset: cheating a bit here: Set to 1 so as to allow for the
|
||||||
|
* leading byte used in bus comms.
|
||||||
|
*
|
||||||
|
* Currently does not provide timestamps. As the hardware doesn't add them they
|
||||||
|
* can only be inferred aproximately from ring buffer events such as 50% full
|
||||||
|
* and knowledge of when buffer was last emptied. This is left to userspace.
|
||||||
|
**/
|
||||||
|
static int sca3000_rip_hw_rb(struct iio_ring_buffer *r,
|
||||||
|
size_t count, u8 **data, int *dead_offset)
|
||||||
|
{
|
||||||
|
struct iio_hw_ring_buffer *hw_ring = iio_to_hw_ring_buf(r);
|
||||||
|
struct iio_dev *indio_dev = hw_ring->private;
|
||||||
|
struct sca3000_state *st = indio_dev->dev_data;
|
||||||
|
u8 *rx;
|
||||||
|
int ret, num_available, num_read = 0;
|
||||||
|
int bytes_per_sample = 1;
|
||||||
|
|
||||||
|
if (st->bpse == 11)
|
||||||
|
bytes_per_sample = 2;
|
||||||
|
|
||||||
|
mutex_lock(&st->lock);
|
||||||
|
/* Check how much data is available:
|
||||||
|
* RFC: Implement an ioctl to not bother checking whether there
|
||||||
|
* is enough data in the ring? Afterall, if we are responding
|
||||||
|
* to an interrupt we have a minimum content guaranteed so it
|
||||||
|
* seems slight silly to waste time checking it is there.
|
||||||
|
*/
|
||||||
|
ret = sca3000_read_data(st,
|
||||||
|
SCA3000_REG_ADDR_BUF_COUNT,
|
||||||
|
&rx, 1);
|
||||||
|
if (ret)
|
||||||
|
goto error_ret;
|
||||||
|
else
|
||||||
|
num_available = rx[1];
|
||||||
|
/* num_available is the total number of samples available
|
||||||
|
* i.e. number of time points * number of channels.
|
||||||
|
*/
|
||||||
|
kfree(rx);
|
||||||
|
if (count > num_available * bytes_per_sample)
|
||||||
|
num_read = num_available*bytes_per_sample;
|
||||||
|
else
|
||||||
|
num_read = count - (count % (bytes_per_sample));
|
||||||
|
|
||||||
|
/* Avoid the read request byte */
|
||||||
|
*dead_offset = 1;
|
||||||
|
ret = sca3000_read_data(st,
|
||||||
|
SCA3000_REG_ADDR_RING_OUT,
|
||||||
|
data, num_read);
|
||||||
|
error_ret:
|
||||||
|
mutex_unlock(&st->lock);
|
||||||
|
|
||||||
|
return ret ? ret : num_read;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* This is only valid with all 3 elements enabled */
|
||||||
|
static int sca3000_ring_get_length(struct iio_ring_buffer *r)
|
||||||
|
{
|
||||||
|
return 64;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* only valid if resolution is kept at 11bits */
|
||||||
|
static int sca3000_ring_get_bpd(struct iio_ring_buffer *r)
|
||||||
|
{
|
||||||
|
return 6;
|
||||||
|
}
|
||||||
|
static void sca3000_ring_release(struct device *dev)
|
||||||
|
{
|
||||||
|
struct iio_ring_buffer *r = to_iio_ring_buffer(dev);
|
||||||
|
kfree(iio_to_hw_ring_buf(r));
|
||||||
|
}
|
||||||
|
|
||||||
|
static IIO_RING_ENABLE_ATTR;
|
||||||
|
static IIO_RING_BPS_ATTR;
|
||||||
|
static IIO_RING_LENGTH_ATTR;
|
||||||
|
|
||||||
|
/**
|
||||||
|
* sca3000_show_ring_bpse() -sysfs function to query bits per sample from ring
|
||||||
|
* @dev: ring buffer device
|
||||||
|
* @attr: this device attribute
|
||||||
|
* @buf: buffer to write to
|
||||||
|
**/
|
||||||
|
static ssize_t sca3000_show_ring_bpse(struct device *dev,
|
||||||
|
struct device_attribute *attr,
|
||||||
|
char *buf)
|
||||||
|
{
|
||||||
|
int len = 0, ret;
|
||||||
|
u8 *rx;
|
||||||
|
struct iio_ring_buffer *r = dev_get_drvdata(dev);
|
||||||
|
struct sca3000_state *st = r->indio_dev->dev_data;
|
||||||
|
|
||||||
|
mutex_lock(&st->lock);
|
||||||
|
ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1);
|
||||||
|
if (ret)
|
||||||
|
goto error_ret;
|
||||||
|
len = sprintf(buf, "%d\n", (rx[1] & SCA3000_RING_BUF_8BIT) ? 8 : 11);
|
||||||
|
kfree(rx);
|
||||||
|
error_ret:
|
||||||
|
mutex_unlock(&st->lock);
|
||||||
|
|
||||||
|
return ret ? ret : len;
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* sca3000_store_ring_bpse() - bits per scan element
|
||||||
|
* @dev: ring buffer device
|
||||||
|
* @attr: attribute called from
|
||||||
|
* @buf: input from userspace
|
||||||
|
* @len: length of input
|
||||||
|
**/
|
||||||
|
static ssize_t sca3000_store_ring_bpse(struct device *dev,
|
||||||
|
struct device_attribute *attr,
|
||||||
|
const char *buf,
|
||||||
|
size_t len)
|
||||||
|
{
|
||||||
|
struct iio_ring_buffer *r = dev_get_drvdata(dev);
|
||||||
|
struct sca3000_state *st = r->indio_dev->dev_data;
|
||||||
|
int ret;
|
||||||
|
u8 *rx;
|
||||||
|
long val;
|
||||||
|
ret = strict_strtol(buf, 10, &val);
|
||||||
|
if (ret)
|
||||||
|
return ret;
|
||||||
|
|
||||||
|
mutex_lock(&st->lock);
|
||||||
|
|
||||||
|
ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1);
|
||||||
|
if (!ret)
|
||||||
|
switch (val) {
|
||||||
|
case 8:
|
||||||
|
ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
|
||||||
|
rx[1] | SCA3000_RING_BUF_8BIT);
|
||||||
|
st->bpse = 8;
|
||||||
|
break;
|
||||||
|
case 11:
|
||||||
|
ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
|
||||||
|
rx[1] & ~SCA3000_RING_BUF_8BIT);
|
||||||
|
st->bpse = 11;
|
||||||
|
break;
|
||||||
|
default:
|
||||||
|
ret = -EINVAL;
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
mutex_unlock(&st->lock);
|
||||||
|
|
||||||
|
return ret ? ret : len;
|
||||||
|
}
|
||||||
|
|
||||||
|
static IIO_CONST_ATTR(bpse_available, "8 11");
|
||||||
|
|
||||||
|
static IIO_DEV_ATTR_BPSE(S_IRUGO | S_IWUSR,
|
||||||
|
sca3000_show_ring_bpse,
|
||||||
|
sca3000_store_ring_bpse);
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Ring buffer attributes
|
||||||
|
* This device is a bit unusual in that the sampling frequency and bpse
|
||||||
|
* only apply to the ring buffer. At all times full rate and accuracy
|
||||||
|
* is available via direct reading from registers.
|
||||||
|
*/
|
||||||
|
static struct attribute *iio_ring_attributes[] = {
|
||||||
|
&dev_attr_length.attr,
|
||||||
|
&dev_attr_bps.attr,
|
||||||
|
&dev_attr_ring_enable.attr,
|
||||||
|
&iio_dev_attr_bpse.dev_attr.attr,
|
||||||
|
&iio_const_attr_bpse_available.dev_attr.attr,
|
||||||
|
NULL,
|
||||||
|
};
|
||||||
|
|
||||||
|
static struct attribute_group sca3000_ring_attr = {
|
||||||
|
.attrs = iio_ring_attributes,
|
||||||
|
};
|
||||||
|
|
||||||
|
static struct attribute_group *sca3000_ring_attr_groups[] = {
|
||||||
|
&sca3000_ring_attr,
|
||||||
|
NULL
|
||||||
|
};
|
||||||
|
|
||||||
|
static struct device_type sca3000_ring_type = {
|
||||||
|
.release = sca3000_ring_release,
|
||||||
|
.groups = sca3000_ring_attr_groups,
|
||||||
|
};
|
||||||
|
|
||||||
|
static struct iio_ring_buffer *sca3000_rb_allocate(struct iio_dev *indio_dev)
|
||||||
|
{
|
||||||
|
struct iio_ring_buffer *buf;
|
||||||
|
struct iio_hw_ring_buffer *ring;
|
||||||
|
|
||||||
|
ring = kzalloc(sizeof *ring, GFP_KERNEL);
|
||||||
|
if (!ring)
|
||||||
|
return 0;
|
||||||
|
ring->private = indio_dev;
|
||||||
|
buf = &ring->buf;
|
||||||
|
iio_ring_buffer_init(buf, indio_dev);
|
||||||
|
buf->dev.type = &sca3000_ring_type;
|
||||||
|
device_initialize(&buf->dev);
|
||||||
|
buf->dev.parent = &indio_dev->dev;
|
||||||
|
dev_set_drvdata(&buf->dev, (void *)buf);
|
||||||
|
|
||||||
|
return buf;
|
||||||
|
}
|
||||||
|
|
||||||
|
static inline void sca3000_rb_free(struct iio_ring_buffer *r)
|
||||||
|
{
|
||||||
|
if (r)
|
||||||
|
iio_put_ring_buffer(r);
|
||||||
|
}
|
||||||
|
|
||||||
|
int sca3000_configure_ring(struct iio_dev *indio_dev)
|
||||||
|
{
|
||||||
|
indio_dev->ring = sca3000_rb_allocate(indio_dev);
|
||||||
|
if (indio_dev->ring == NULL)
|
||||||
|
return -ENOMEM;
|
||||||
|
indio_dev->modes |= INDIO_RING_HARDWARE_BUFFER;
|
||||||
|
|
||||||
|
indio_dev->ring->access.rip_lots = &sca3000_rip_hw_rb;
|
||||||
|
indio_dev->ring->access.get_length = &sca3000_ring_get_length;
|
||||||
|
indio_dev->ring->access.get_bpd = &sca3000_ring_get_bpd;
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
void sca3000_unconfigure_ring(struct iio_dev *indio_dev)
|
||||||
|
{
|
||||||
|
sca3000_rb_free(indio_dev->ring);
|
||||||
|
}
|
||||||
|
|
||||||
|
static inline
|
||||||
|
int __sca3000_hw_ring_state_set(struct iio_dev *indio_dev, bool state)
|
||||||
|
{
|
||||||
|
struct sca3000_state *st = indio_dev->dev_data;
|
||||||
|
int ret;
|
||||||
|
u8 *rx;
|
||||||
|
|
||||||
|
mutex_lock(&st->lock);
|
||||||
|
ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1);
|
||||||
|
if (ret)
|
||||||
|
goto error_ret;
|
||||||
|
if (state) {
|
||||||
|
printk(KERN_INFO "supposedly enabling ring buffer\n");
|
||||||
|
ret = sca3000_write_reg(st,
|
||||||
|
SCA3000_REG_ADDR_MODE,
|
||||||
|
(rx[1] | SCA3000_RING_BUF_ENABLE));
|
||||||
|
} else
|
||||||
|
ret = sca3000_write_reg(st,
|
||||||
|
SCA3000_REG_ADDR_MODE,
|
||||||
|
(rx[1] & ~SCA3000_RING_BUF_ENABLE));
|
||||||
|
kfree(rx);
|
||||||
|
error_ret:
|
||||||
|
mutex_unlock(&st->lock);
|
||||||
|
|
||||||
|
return ret;
|
||||||
|
}
|
||||||
|
/**
|
||||||
|
* sca3000_hw_ring_preenable() hw ring buffer preenable function
|
||||||
|
*
|
||||||
|
* Very simple enable function as the chip will allows normal reads
|
||||||
|
* during ring buffer operation so as long as it is indeed running
|
||||||
|
* before we notify the core, the precise ordering does not matter.
|
||||||
|
**/
|
||||||
|
static int sca3000_hw_ring_preenable(struct iio_dev *indio_dev)
|
||||||
|
{
|
||||||
|
return __sca3000_hw_ring_state_set(indio_dev, 1);
|
||||||
|
}
|
||||||
|
|
||||||
|
static int sca3000_hw_ring_postdisable(struct iio_dev *indio_dev)
|
||||||
|
{
|
||||||
|
return __sca3000_hw_ring_state_set(indio_dev, 0);
|
||||||
|
}
|
||||||
|
|
||||||
|
void sca3000_register_ring_funcs(struct iio_dev *indio_dev)
|
||||||
|
{
|
||||||
|
indio_dev->ring->preenable = &sca3000_hw_ring_preenable;
|
||||||
|
indio_dev->ring->postdisable = &sca3000_hw_ring_postdisable;
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* sca3000_ring_int_process() ring specific interrupt handling.
|
||||||
|
*
|
||||||
|
* This is only split from the main interrupt handler so as to
|
||||||
|
* reduce the amount of code if the ring buffer is not enabled.
|
||||||
|
**/
|
||||||
|
void sca3000_ring_int_process(u8 val, struct iio_ring_buffer *ring)
|
||||||
|
{
|
||||||
|
if (val & SCA3000_INT_STATUS_THREE_QUARTERS)
|
||||||
|
iio_push_or_escallate_ring_event(ring,
|
||||||
|
IIO_EVENT_CODE_RING_75_FULL,
|
||||||
|
0);
|
||||||
|
else if (val & SCA3000_INT_STATUS_HALF)
|
||||||
|
iio_push_ring_event(ring,
|
||||||
|
IIO_EVENT_CODE_RING_50_FULL, 0);
|
||||||
|
}
|
||||||
|
|
@ -0,0 +1,22 @@
|
||||||
|
/*
|
||||||
|
* ring_hw.h - common functionality for iio hardware ring buffers
|
||||||
|
*
|
||||||
|
* This program is free software; you can redistribute it and/or modify it
|
||||||
|
* under the terms of the GNU General Public License version 2 as published by
|
||||||
|
* the Free Software Foundation.
|
||||||
|
*
|
||||||
|
* Copyright (c) 2009 Jonathan Cameron <jic23@cam.ac.uk>
|
||||||
|
*
|
||||||
|
*/
|
||||||
|
|
||||||
|
/**
|
||||||
|
* struct iio_hw_ring_buffer- hardware ring buffer
|
||||||
|
* @buf: generic ring buffer elements
|
||||||
|
* @private: device specific data
|
||||||
|
*/
|
||||||
|
struct iio_hw_ring_buffer {
|
||||||
|
struct iio_ring_buffer buf;
|
||||||
|
void *private;
|
||||||
|
};
|
||||||
|
|
||||||
|
#define iio_to_hw_ring_buf(r) container_of(r, struct iio_hw_ring_buffer, buf)
|
||||||
Loading…
Reference in New Issue