staging: iio: adc: Enable driver support for ad7887 AD converter
Enable support for AD7887: SPI Micropower, 2-Channel, 125 kSPS, 12-Bit ADC staging: iio: adc: Fix according to review feedback Review feedback by Jonathan Cameron: Combine statements. Document struct members. Remove redundant variable initialization. Simplify multichannel scan from ring logic. Fix coding style. [v2] staging: iio: adc: ad7887: Fix typos Signed-off-by: Michael Hennerich <michael.hennerich@analog.com> Acked-by: Jonathan Cameron <jic23@cam.ac.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Michael Hennerich
Greg Kroah-Hartman
parent
b5a4948175
commit
2b4756aa36
5 changed files with 694 additions and 0 deletions
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@ -97,6 +97,20 @@ config AD7476
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To compile this driver as a module, choose M here: the
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To compile this driver as a module, choose M here: the
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module will be called ad7476.
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module will be called ad7476.
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config AD7887
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tristate "Analog Devices AD7887 ADC driver"
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depends on SPI
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select IIO_RING_BUFFER
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select IIO_SW_RING
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select IIO_TRIGGER
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help
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Say yes here to build support for Analog Devices
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AD7887 SPI analog to digital convertor (ADC).
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If unsure, say N (but it's safe to say "Y").
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To compile this driver as a module, choose M here: the
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module will be called ad7887.
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config AD7745
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config AD7745
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tristate "Analog Devices AD7745, AD7746 AD7747 capacitive sensor driver"
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tristate "Analog Devices AD7745, AD7746 AD7747 capacitive sensor driver"
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depends on I2C
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depends on I2C
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@ -15,6 +15,10 @@ ad7476-y := ad7476_core.o
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ad7476-$(CONFIG_IIO_RING_BUFFER) += ad7476_ring.o
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ad7476-$(CONFIG_IIO_RING_BUFFER) += ad7476_ring.o
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obj-$(CONFIG_AD7476) += ad7476.o
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obj-$(CONFIG_AD7476) += ad7476.o
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ad7887-y := ad7887_core.o
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ad7887-$(CONFIG_IIO_RING_BUFFER) += ad7887_ring.o
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obj-$(CONFIG_AD7887) += ad7887.o
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obj-$(CONFIG_AD7150) += ad7150.o
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obj-$(CONFIG_AD7150) += ad7150.o
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obj-$(CONFIG_AD7152) += ad7152.o
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obj-$(CONFIG_AD7152) += ad7152.o
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obj-$(CONFIG_AD7291) += ad7291.o
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obj-$(CONFIG_AD7291) += ad7291.o
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105
drivers/staging/iio/adc/ad7887.h
Normal file
105
drivers/staging/iio/adc/ad7887.h
Normal file
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@ -0,0 +1,105 @@
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/*
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* AD7887 SPI ADC driver
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*
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* Copyright 2010 Analog Devices Inc.
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*
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* Licensed under the GPL-2 or later.
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*/
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#ifndef IIO_ADC_AD7887_H_
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#define IIO_ADC_AD7887_H_
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#define AD7887_REF_DIS (1 << 5) /* on-chip reference disable */
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#define AD7887_DUAL (1 << 4) /* dual-channel mode */
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#define AD7887_CH_AIN1 (1 << 3) /* convert on channel 1, DUAL=1 */
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#define AD7887_CH_AIN0 (0 << 3) /* convert on channel 0, DUAL=0,1 */
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#define AD7887_PM_MODE1 (0) /* CS based shutdown */
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#define AD7887_PM_MODE2 (1) /* full on */
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#define AD7887_PM_MODE3 (2) /* auto shutdown after conversion */
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#define AD7887_PM_MODE4 (3) /* standby mode */
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enum ad7887_channels {
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AD7887_CH0,
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AD7887_CH0_CH1,
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AD7887_CH1,
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};
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#define RES_MASK(bits) ((1 << (bits)) - 1) /* TODO: move this into a common header */
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/*
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* TODO: struct ad7887_platform_data needs to go into include/linux/iio
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*/
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struct ad7887_platform_data {
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/* External Vref voltage applied */
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u16 vref_mv;
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/*
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* AD7887:
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* In single channel mode en_dual = flase, AIN1/Vref pins assumes its
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* Vref function. In dual channel mode en_dual = true, AIN1 becomes the
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* second input channel, and Vref is internally connected to Vdd.
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*/
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bool en_dual;
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/*
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* AD7887:
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* use_onchip_ref = true, the Vref is internally connected to the 2.500V
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* Voltage reference. If use_onchip_ref = false, the reference voltage
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* is supplied by AIN1/Vref
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*/
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bool use_onchip_ref;
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};
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struct ad7887_chip_info {
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u8 bits; /* number of ADC bits */
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u8 storagebits; /* number of bits read from the ADC */
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u8 left_shift; /* number of bits the sample must be shifted */
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char sign; /* [s]igned or [u]nsigned */
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u16 int_vref_mv; /* internal reference voltage */
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};
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struct ad7887_state {
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struct iio_dev *indio_dev;
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struct spi_device *spi;
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const struct ad7887_chip_info *chip_info;
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struct regulator *reg;
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struct work_struct poll_work;
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atomic_t protect_ring;
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u16 int_vref_mv;
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bool en_dual;
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struct spi_transfer xfer[4];
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struct spi_message msg[3];
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struct spi_message *ring_msg;
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unsigned char tx_cmd_buf[8];
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/*
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* DMA (thus cache coherency maintenance) requires the
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* transfer buffers to live in their own cache lines.
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*/
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unsigned char data[4] ____cacheline_aligned;
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};
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enum ad7887_supported_device_ids {
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ID_AD7887
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};
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#ifdef CONFIG_IIO_RING_BUFFER
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int ad7887_scan_from_ring(struct ad7887_state *st, long mask);
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int ad7887_register_ring_funcs_and_init(struct iio_dev *indio_dev);
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void ad7887_ring_cleanup(struct iio_dev *indio_dev);
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#else /* CONFIG_IIO_RING_BUFFER */
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static inline int ad7887_scan_from_ring(struct ad7887_state *st, long mask)
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{
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return 0;
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}
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static inline int
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ad7887_register_ring_funcs_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 ad7887_ring_cleanup(struct iio_dev *indio_dev)
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{
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}
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#endif /* CONFIG_IIO_RING_BUFFER */
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#endif /* IIO_ADC_AD7887_H_ */
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305
drivers/staging/iio/adc/ad7887_core.c
Normal file
305
drivers/staging/iio/adc/ad7887_core.c
Normal file
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@ -0,0 +1,305 @@
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/*
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* AD7887 SPI ADC driver
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*
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* Copyright 2010 Analog Devices Inc.
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*
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* Licensed under the GPL-2 or later.
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*/
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#include <linux/interrupt.h>
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#include <linux/workqueue.h>
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#include <linux/device.h>
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/sysfs.h>
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#include <linux/list.h>
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#include <linux/spi/spi.h>
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#include <linux/regulator/consumer.h>
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#include <linux/err.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 "adc.h"
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#include "ad7887.h"
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static int ad7887_scan_direct(struct ad7887_state *st, unsigned ch)
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{
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int ret = spi_sync(st->spi, &st->msg[ch]);
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if (ret)
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return ret;
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return (st->data[(ch * 2)] << 8) | st->data[(ch * 2) + 1];
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}
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static ssize_t ad7887_scan(struct device *dev,
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struct device_attribute *attr,
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char *buf)
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{
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struct iio_dev *dev_info = dev_get_drvdata(dev);
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struct ad7887_state *st = dev_info->dev_data;
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struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
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int ret;
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mutex_lock(&dev_info->mlock);
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if (iio_ring_enabled(dev_info))
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ret = ad7887_scan_from_ring(st, 1 << this_attr->address);
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else
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ret = ad7887_scan_direct(st, this_attr->address);
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mutex_unlock(&dev_info->mlock);
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if (ret < 0)
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return ret;
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return sprintf(buf, "%d\n", (ret >> st->chip_info->left_shift) &
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RES_MASK(st->chip_info->bits));
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}
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static IIO_DEV_ATTR_IN_RAW(0, ad7887_scan, 0);
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static IIO_DEV_ATTR_IN_RAW(1, ad7887_scan, 1);
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static ssize_t ad7887_show_scale(struct device *dev,
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struct device_attribute *attr,
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char *buf)
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{
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/* Driver currently only support internal vref */
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struct iio_dev *dev_info = dev_get_drvdata(dev);
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struct ad7887_state *st = iio_dev_get_devdata(dev_info);
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/* Corresponds to Vref / 2^(bits) */
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unsigned int scale_uv = (st->int_vref_mv * 1000) >> st->chip_info->bits;
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return sprintf(buf, "%d.%d\n", scale_uv / 1000, scale_uv % 1000);
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}
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static IIO_DEVICE_ATTR(in_scale, S_IRUGO, ad7887_show_scale, NULL, 0);
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static ssize_t ad7887_show_name(struct device *dev,
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struct device_attribute *attr,
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char *buf)
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{
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struct iio_dev *dev_info = dev_get_drvdata(dev);
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struct ad7887_state *st = iio_dev_get_devdata(dev_info);
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return sprintf(buf, "%s\n", spi_get_device_id(st->spi)->name);
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}
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static IIO_DEVICE_ATTR(name, S_IRUGO, ad7887_show_name, NULL, 0);
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static struct attribute *ad7887_attributes[] = {
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&iio_dev_attr_in0_raw.dev_attr.attr,
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&iio_dev_attr_in1_raw.dev_attr.attr,
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&iio_dev_attr_in_scale.dev_attr.attr,
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&iio_dev_attr_name.dev_attr.attr,
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NULL,
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};
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static mode_t ad7887_attr_is_visible(struct kobject *kobj,
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struct attribute *attr, int n)
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{
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struct device *dev = container_of(kobj, struct device, kobj);
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struct iio_dev *dev_info = dev_get_drvdata(dev);
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struct ad7887_state *st = iio_dev_get_devdata(dev_info);
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mode_t mode = attr->mode;
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if ((attr == &iio_dev_attr_in1_raw.dev_attr.attr) && !st->en_dual)
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mode = 0;
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return mode;
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}
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static const struct attribute_group ad7887_attribute_group = {
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.attrs = ad7887_attributes,
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.is_visible = ad7887_attr_is_visible,
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};
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static const struct ad7887_chip_info ad7887_chip_info_tbl[] = {
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/*
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* More devices added in future
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*/
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[ID_AD7887] = {
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.bits = 12,
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.storagebits = 16,
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.left_shift = 0,
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.sign = IIO_SCAN_EL_TYPE_UNSIGNED,
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.int_vref_mv = 2500,
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},
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};
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static int __devinit ad7887_probe(struct spi_device *spi)
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{
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struct ad7887_platform_data *pdata = spi->dev.platform_data;
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struct ad7887_state *st;
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int ret, voltage_uv = 0;
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st = kzalloc(sizeof(*st), GFP_KERNEL);
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if (st == NULL) {
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ret = -ENOMEM;
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goto error_ret;
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}
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st->reg = regulator_get(&spi->dev, "vcc");
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if (!IS_ERR(st->reg)) {
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ret = regulator_enable(st->reg);
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if (ret)
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goto error_put_reg;
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voltage_uv = regulator_get_voltage(st->reg);
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}
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st->chip_info =
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&ad7887_chip_info_tbl[spi_get_device_id(spi)->driver_data];
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spi_set_drvdata(spi, st);
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atomic_set(&st->protect_ring, 0);
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st->spi = spi;
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st->indio_dev = iio_allocate_device();
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if (st->indio_dev == NULL) {
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ret = -ENOMEM;
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goto error_disable_reg;
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}
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/* Estabilish that the iio_dev is a child of the spi device */
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st->indio_dev->dev.parent = &spi->dev;
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st->indio_dev->attrs = &ad7887_attribute_group;
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st->indio_dev->dev_data = (void *)(st);
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st->indio_dev->driver_module = THIS_MODULE;
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st->indio_dev->modes = INDIO_DIRECT_MODE;
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/* Setup default message */
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st->tx_cmd_buf[0] = AD7887_CH_AIN0 | AD7887_PM_MODE4 |
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((pdata && pdata->use_onchip_ref) ?
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0 : AD7887_REF_DIS);
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st->xfer[0].rx_buf = &st->data[0];
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st->xfer[0].tx_buf = &st->tx_cmd_buf[0];
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st->xfer[0].len = 2;
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spi_message_init(&st->msg[AD7887_CH0]);
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spi_message_add_tail(&st->xfer[0], &st->msg[AD7887_CH0]);
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if (pdata && pdata->en_dual) {
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st->tx_cmd_buf[0] |= AD7887_DUAL | AD7887_REF_DIS;
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st->tx_cmd_buf[2] = AD7887_CH_AIN1 | AD7887_DUAL |
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AD7887_REF_DIS | AD7887_PM_MODE4;
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st->tx_cmd_buf[4] = AD7887_CH_AIN0 | AD7887_DUAL |
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AD7887_REF_DIS | AD7887_PM_MODE4;
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st->tx_cmd_buf[6] = AD7887_CH_AIN1 | AD7887_DUAL |
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AD7887_REF_DIS | AD7887_PM_MODE4;
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st->xfer[1].rx_buf = &st->data[0];
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st->xfer[1].tx_buf = &st->tx_cmd_buf[2];
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st->xfer[1].len = 2;
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st->xfer[2].rx_buf = &st->data[2];
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st->xfer[2].tx_buf = &st->tx_cmd_buf[4];
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st->xfer[2].len = 2;
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spi_message_init(&st->msg[AD7887_CH0_CH1]);
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spi_message_add_tail(&st->xfer[1], &st->msg[AD7887_CH0_CH1]);
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spi_message_add_tail(&st->xfer[2], &st->msg[AD7887_CH0_CH1]);
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st->xfer[3].rx_buf = &st->data[0];
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||||||
|
st->xfer[3].tx_buf = &st->tx_cmd_buf[6];
|
||||||
|
st->xfer[3].len = 2;
|
||||||
|
|
||||||
|
spi_message_init(&st->msg[AD7887_CH1]);
|
||||||
|
spi_message_add_tail(&st->xfer[3], &st->msg[AD7887_CH1]);
|
||||||
|
|
||||||
|
st->en_dual = true;
|
||||||
|
|
||||||
|
if (pdata && pdata->vref_mv)
|
||||||
|
st->int_vref_mv = pdata->vref_mv;
|
||||||
|
else if (voltage_uv)
|
||||||
|
st->int_vref_mv = voltage_uv / 1000;
|
||||||
|
else
|
||||||
|
dev_warn(&spi->dev, "reference voltage unspecified\n");
|
||||||
|
|
||||||
|
} else {
|
||||||
|
if (pdata && pdata->vref_mv)
|
||||||
|
st->int_vref_mv = pdata->vref_mv;
|
||||||
|
else if (pdata && pdata->use_onchip_ref)
|
||||||
|
st->int_vref_mv = st->chip_info->int_vref_mv;
|
||||||
|
else
|
||||||
|
dev_warn(&spi->dev, "reference voltage unspecified\n");
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
ret = ad7887_register_ring_funcs_and_init(st->indio_dev);
|
||||||
|
if (ret)
|
||||||
|
goto error_free_device;
|
||||||
|
|
||||||
|
ret = iio_device_register(st->indio_dev);
|
||||||
|
if (ret)
|
||||||
|
goto error_free_device;
|
||||||
|
|
||||||
|
ret = iio_ring_buffer_register(st->indio_dev->ring, 0);
|
||||||
|
if (ret)
|
||||||
|
goto error_cleanup_ring;
|
||||||
|
return 0;
|
||||||
|
|
||||||
|
error_cleanup_ring:
|
||||||
|
ad7887_ring_cleanup(st->indio_dev);
|
||||||
|
iio_device_unregister(st->indio_dev);
|
||||||
|
error_free_device:
|
||||||
|
iio_free_device(st->indio_dev);
|
||||||
|
error_disable_reg:
|
||||||
|
if (!IS_ERR(st->reg))
|
||||||
|
regulator_disable(st->reg);
|
||||||
|
error_put_reg:
|
||||||
|
if (!IS_ERR(st->reg))
|
||||||
|
regulator_put(st->reg);
|
||||||
|
kfree(st);
|
||||||
|
error_ret:
|
||||||
|
return ret;
|
||||||
|
}
|
||||||
|
|
||||||
|
static int ad7887_remove(struct spi_device *spi)
|
||||||
|
{
|
||||||
|
struct ad7887_state *st = spi_get_drvdata(spi);
|
||||||
|
struct iio_dev *indio_dev = st->indio_dev;
|
||||||
|
iio_ring_buffer_unregister(indio_dev->ring);
|
||||||
|
ad7887_ring_cleanup(indio_dev);
|
||||||
|
iio_device_unregister(indio_dev);
|
||||||
|
if (!IS_ERR(st->reg)) {
|
||||||
|
regulator_disable(st->reg);
|
||||||
|
regulator_put(st->reg);
|
||||||
|
}
|
||||||
|
kfree(st);
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
static const struct spi_device_id ad7887_id[] = {
|
||||||
|
{"ad7887", ID_AD7887},
|
||||||
|
{}
|
||||||
|
};
|
||||||
|
|
||||||
|
static struct spi_driver ad7887_driver = {
|
||||||
|
.driver = {
|
||||||
|
.name = "ad7887",
|
||||||
|
.bus = &spi_bus_type,
|
||||||
|
.owner = THIS_MODULE,
|
||||||
|
},
|
||||||
|
.probe = ad7887_probe,
|
||||||
|
.remove = __devexit_p(ad7887_remove),
|
||||||
|
.id_table = ad7887_id,
|
||||||
|
};
|
||||||
|
|
||||||
|
static int __init ad7887_init(void)
|
||||||
|
{
|
||||||
|
return spi_register_driver(&ad7887_driver);
|
||||||
|
}
|
||||||
|
module_init(ad7887_init);
|
||||||
|
|
||||||
|
static void __exit ad7887_exit(void)
|
||||||
|
{
|
||||||
|
spi_unregister_driver(&ad7887_driver);
|
||||||
|
}
|
||||||
|
module_exit(ad7887_exit);
|
||||||
|
|
||||||
|
MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
|
||||||
|
MODULE_DESCRIPTION("Analog Devices AD7887 ADC");
|
||||||
|
MODULE_LICENSE("GPL v2");
|
||||||
|
MODULE_ALIAS("spi:ad7887");
|
||||||
266
drivers/staging/iio/adc/ad7887_ring.c
Normal file
266
drivers/staging/iio/adc/ad7887_ring.c
Normal file
|
|
@ -0,0 +1,266 @@
|
||||||
|
/*
|
||||||
|
* Copyright 2010 Analog Devices Inc.
|
||||||
|
* Copyright (C) 2008 Jonathan Cameron
|
||||||
|
*
|
||||||
|
* Licensed under the GPL-2 or later.
|
||||||
|
*
|
||||||
|
* ad7887_ring.c
|
||||||
|
*/
|
||||||
|
|
||||||
|
#include <linux/interrupt.h>
|
||||||
|
#include <linux/gpio.h>
|
||||||
|
#include <linux/workqueue.h>
|
||||||
|
#include <linux/device.h>
|
||||||
|
#include <linux/kernel.h>
|
||||||
|
#include <linux/slab.h>
|
||||||
|
#include <linux/sysfs.h>
|
||||||
|
#include <linux/list.h>
|
||||||
|
#include <linux/spi/spi.h>
|
||||||
|
|
||||||
|
#include "../iio.h"
|
||||||
|
#include "../ring_generic.h"
|
||||||
|
#include "../ring_sw.h"
|
||||||
|
#include "../trigger.h"
|
||||||
|
#include "../sysfs.h"
|
||||||
|
|
||||||
|
#include "ad7887.h"
|
||||||
|
|
||||||
|
static IIO_SCAN_EL_C(in0, 0, 0, NULL);
|
||||||
|
static IIO_SCAN_EL_C(in1, 1, 0, NULL);
|
||||||
|
|
||||||
|
static ssize_t ad7887_show_type(struct device *dev,
|
||||||
|
struct device_attribute *attr,
|
||||||
|
char *buf)
|
||||||
|
{
|
||||||
|
struct iio_ring_buffer *ring = dev_get_drvdata(dev);
|
||||||
|
struct iio_dev *indio_dev = ring->indio_dev;
|
||||||
|
struct ad7887_state *st = indio_dev->dev_data;
|
||||||
|
|
||||||
|
return sprintf(buf, "%c%d/%d>>%d\n", st->chip_info->sign,
|
||||||
|
st->chip_info->bits, st->chip_info->storagebits,
|
||||||
|
st->chip_info->left_shift);
|
||||||
|
}
|
||||||
|
static IIO_DEVICE_ATTR(in_type, S_IRUGO, ad7887_show_type, NULL, 0);
|
||||||
|
|
||||||
|
static struct attribute *ad7887_scan_el_attrs[] = {
|
||||||
|
&iio_scan_el_in0.dev_attr.attr,
|
||||||
|
&iio_const_attr_in0_index.dev_attr.attr,
|
||||||
|
&iio_scan_el_in1.dev_attr.attr,
|
||||||
|
&iio_const_attr_in1_index.dev_attr.attr,
|
||||||
|
&iio_dev_attr_in_type.dev_attr.attr,
|
||||||
|
NULL,
|
||||||
|
};
|
||||||
|
|
||||||
|
static mode_t ad7887_scan_el_attr_is_visible(struct kobject *kobj,
|
||||||
|
struct attribute *attr, int n)
|
||||||
|
{
|
||||||
|
struct device *dev = container_of(kobj, struct device, kobj);
|
||||||
|
struct iio_ring_buffer *ring = dev_get_drvdata(dev);
|
||||||
|
struct iio_dev *indio_dev = ring->indio_dev;
|
||||||
|
struct ad7887_state *st = indio_dev->dev_data;
|
||||||
|
|
||||||
|
mode_t mode = attr->mode;
|
||||||
|
|
||||||
|
if ((attr == &iio_scan_el_in1.dev_attr.attr) ||
|
||||||
|
(attr == &iio_const_attr_in1_index.dev_attr.attr))
|
||||||
|
if (!st->en_dual)
|
||||||
|
mode = 0;
|
||||||
|
|
||||||
|
return mode;
|
||||||
|
}
|
||||||
|
|
||||||
|
static struct attribute_group ad7887_scan_el_group = {
|
||||||
|
.name = "scan_elements",
|
||||||
|
.attrs = ad7887_scan_el_attrs,
|
||||||
|
.is_visible = ad7887_scan_el_attr_is_visible,
|
||||||
|
};
|
||||||
|
|
||||||
|
int ad7887_scan_from_ring(struct ad7887_state *st, long mask)
|
||||||
|
{
|
||||||
|
struct iio_ring_buffer *ring = st->indio_dev->ring;
|
||||||
|
int count = 0, ret;
|
||||||
|
u16 *ring_data;
|
||||||
|
|
||||||
|
if (!(ring->scan_mask & mask)) {
|
||||||
|
ret = -EBUSY;
|
||||||
|
goto error_ret;
|
||||||
|
}
|
||||||
|
|
||||||
|
ring_data = kmalloc(ring->access.get_bytes_per_datum(ring), GFP_KERNEL);
|
||||||
|
if (ring_data == NULL) {
|
||||||
|
ret = -ENOMEM;
|
||||||
|
goto error_ret;
|
||||||
|
}
|
||||||
|
ret = ring->access.read_last(ring, (u8 *) ring_data);
|
||||||
|
if (ret)
|
||||||
|
goto error_free_ring_data;
|
||||||
|
|
||||||
|
/* for single channel scan the result is stored with zero offset */
|
||||||
|
if ((ring->scan_mask == ((1 << 1) | (1 << 0))) && (mask == (1 << 1)))
|
||||||
|
count = 1;
|
||||||
|
|
||||||
|
ret = be16_to_cpu(ring_data[count]);
|
||||||
|
|
||||||
|
error_free_ring_data:
|
||||||
|
kfree(ring_data);
|
||||||
|
error_ret:
|
||||||
|
return ret;
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* ad7887_ring_preenable() setup the parameters of the ring before enabling
|
||||||
|
*
|
||||||
|
* The complex nature of the setting of the nuber of bytes per datum is due
|
||||||
|
* to this driver currently ensuring that the timestamp is stored at an 8
|
||||||
|
* byte boundary.
|
||||||
|
**/
|
||||||
|
static int ad7887_ring_preenable(struct iio_dev *indio_dev)
|
||||||
|
{
|
||||||
|
struct ad7887_state *st = indio_dev->dev_data;
|
||||||
|
struct iio_ring_buffer *ring = indio_dev->ring;
|
||||||
|
size_t d_size;
|
||||||
|
|
||||||
|
if (indio_dev->ring->access.set_bytes_per_datum) {
|
||||||
|
d_size = st->chip_info->storagebits / 8 + sizeof(s64);
|
||||||
|
if (d_size % 8)
|
||||||
|
d_size += 8 - (d_size % 8);
|
||||||
|
indio_dev->ring->access.set_bytes_per_datum(indio_dev->ring,
|
||||||
|
d_size);
|
||||||
|
}
|
||||||
|
|
||||||
|
switch (ring->scan_mask) {
|
||||||
|
case (1 << 0):
|
||||||
|
st->ring_msg = &st->msg[AD7887_CH0];
|
||||||
|
break;
|
||||||
|
case (1 << 1):
|
||||||
|
st->ring_msg = &st->msg[AD7887_CH1];
|
||||||
|
/* Dummy read: push CH1 setting down to hardware */
|
||||||
|
spi_sync(st->spi, st->ring_msg);
|
||||||
|
break;
|
||||||
|
case ((1 << 1) | (1 << 0)):
|
||||||
|
st->ring_msg = &st->msg[AD7887_CH0_CH1];
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
static int ad7887_ring_postdisable(struct iio_dev *indio_dev)
|
||||||
|
{
|
||||||
|
struct ad7887_state *st = indio_dev->dev_data;
|
||||||
|
|
||||||
|
/* dummy read: restore default CH0 settin */
|
||||||
|
return spi_sync(st->spi, &st->msg[AD7887_CH0]);
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* ad7887_poll_func_th() th of trigger launched polling to ring buffer
|
||||||
|
*
|
||||||
|
* As sampling only occurs on spi comms occuring, leave timestamping until
|
||||||
|
* then. Some triggers will generate their own time stamp. Currently
|
||||||
|
* there is no way of notifying them when no one cares.
|
||||||
|
**/
|
||||||
|
static void ad7887_poll_func_th(struct iio_dev *indio_dev, s64 time)
|
||||||
|
{
|
||||||
|
struct ad7887_state *st = indio_dev->dev_data;
|
||||||
|
|
||||||
|
schedule_work(&st->poll_work);
|
||||||
|
return;
|
||||||
|
}
|
||||||
|
/**
|
||||||
|
* ad7887_poll_bh_to_ring() bh of trigger launched polling to ring buffer
|
||||||
|
* @work_s: the work struct through which this was scheduled
|
||||||
|
*
|
||||||
|
* Currently there is no option in this driver to disable the saving of
|
||||||
|
* timestamps within the ring.
|
||||||
|
* I think the one copy of this at a time was to avoid problems if the
|
||||||
|
* trigger was set far too high and the reads then locked up the computer.
|
||||||
|
**/
|
||||||
|
static void ad7887_poll_bh_to_ring(struct work_struct *work_s)
|
||||||
|
{
|
||||||
|
struct ad7887_state *st = container_of(work_s, struct ad7887_state,
|
||||||
|
poll_work);
|
||||||
|
struct iio_dev *indio_dev = st->indio_dev;
|
||||||
|
struct iio_sw_ring_buffer *sw_ring = iio_to_sw_ring(indio_dev->ring);
|
||||||
|
struct iio_ring_buffer *ring = indio_dev->ring;
|
||||||
|
s64 time_ns;
|
||||||
|
__u8 *buf;
|
||||||
|
int b_sent;
|
||||||
|
size_t d_size;
|
||||||
|
|
||||||
|
unsigned int bytes = ring->scan_count * st->chip_info->storagebits / 8;
|
||||||
|
|
||||||
|
/* Ensure the timestamp is 8 byte aligned */
|
||||||
|
d_size = bytes + sizeof(s64);
|
||||||
|
if (d_size % sizeof(s64))
|
||||||
|
d_size += sizeof(s64) - (d_size % sizeof(s64));
|
||||||
|
|
||||||
|
/* Ensure only one copy of this function running at a time */
|
||||||
|
if (atomic_inc_return(&st->protect_ring) > 1)
|
||||||
|
return;
|
||||||
|
|
||||||
|
buf = kzalloc(d_size, GFP_KERNEL);
|
||||||
|
if (buf == NULL)
|
||||||
|
return;
|
||||||
|
|
||||||
|
b_sent = spi_sync(st->spi, st->ring_msg);
|
||||||
|
if (b_sent)
|
||||||
|
goto done;
|
||||||
|
|
||||||
|
time_ns = iio_get_time_ns();
|
||||||
|
|
||||||
|
memcpy(buf, st->data, bytes);
|
||||||
|
memcpy(buf + d_size - sizeof(s64), &time_ns, sizeof(time_ns));
|
||||||
|
|
||||||
|
indio_dev->ring->access.store_to(&sw_ring->buf, buf, time_ns);
|
||||||
|
done:
|
||||||
|
kfree(buf);
|
||||||
|
atomic_dec(&st->protect_ring);
|
||||||
|
}
|
||||||
|
|
||||||
|
int ad7887_register_ring_funcs_and_init(struct iio_dev *indio_dev)
|
||||||
|
{
|
||||||
|
struct ad7887_state *st = indio_dev->dev_data;
|
||||||
|
int ret;
|
||||||
|
|
||||||
|
indio_dev->ring = iio_sw_rb_allocate(indio_dev);
|
||||||
|
if (!indio_dev->ring) {
|
||||||
|
ret = -ENOMEM;
|
||||||
|
goto error_ret;
|
||||||
|
}
|
||||||
|
/* Effectively select the ring buffer implementation */
|
||||||
|
iio_ring_sw_register_funcs(&indio_dev->ring->access);
|
||||||
|
ret = iio_alloc_pollfunc(indio_dev, NULL, &ad7887_poll_func_th);
|
||||||
|
if (ret)
|
||||||
|
goto error_deallocate_sw_rb;
|
||||||
|
|
||||||
|
/* Ring buffer functions - here trigger setup related */
|
||||||
|
|
||||||
|
indio_dev->ring->preenable = &ad7887_ring_preenable;
|
||||||
|
indio_dev->ring->postenable = &iio_triggered_ring_postenable;
|
||||||
|
indio_dev->ring->predisable = &iio_triggered_ring_predisable;
|
||||||
|
indio_dev->ring->postdisable = &ad7887_ring_postdisable;
|
||||||
|
indio_dev->ring->scan_el_attrs = &ad7887_scan_el_group;
|
||||||
|
|
||||||
|
INIT_WORK(&st->poll_work, &ad7887_poll_bh_to_ring);
|
||||||
|
|
||||||
|
/* Flag that polled ring buffering is possible */
|
||||||
|
indio_dev->modes |= INDIO_RING_TRIGGERED;
|
||||||
|
return 0;
|
||||||
|
error_deallocate_sw_rb:
|
||||||
|
iio_sw_rb_free(indio_dev->ring);
|
||||||
|
error_ret:
|
||||||
|
return ret;
|
||||||
|
}
|
||||||
|
|
||||||
|
void ad7887_ring_cleanup(struct iio_dev *indio_dev)
|
||||||
|
{
|
||||||
|
/* ensure that the trigger has been detached */
|
||||||
|
if (indio_dev->trig) {
|
||||||
|
iio_put_trigger(indio_dev->trig);
|
||||||
|
iio_trigger_dettach_poll_func(indio_dev->trig,
|
||||||
|
indio_dev->pollfunc);
|
||||||
|
}
|
||||||
|
kfree(indio_dev->pollfunc);
|
||||||
|
iio_sw_rb_free(indio_dev->ring);
|
||||||
|
}
|
||||||
Reference in a new issue