2019-05-28 16:57:06 +00:00
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// SPDX-License-Identifier: GPL-2.0-only
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2010-11-22 13:35:32 +00:00
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/*
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* AD7887 SPI ADC driver
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*
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2011-05-18 13:41:50 +00:00
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* Copyright 2010-2011 Analog Devices Inc.
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2010-11-22 13:35:32 +00:00
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*/
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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/spi/spi.h>
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#include <linux/regulator/consumer.h>
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#include <linux/err.h>
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2011-07-03 19:49:50 +00:00
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#include <linux/module.h>
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2012-11-05 09:56:00 +00:00
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#include <linux/interrupt.h>
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2014-12-06 06:00:00 +00:00
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#include <linux/bitops.h>
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2010-11-22 13:35:32 +00:00
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2012-04-25 14:54:58 +00:00
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#include <linux/iio/iio.h>
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#include <linux/iio/sysfs.h>
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#include <linux/iio/buffer.h>
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2011-08-12 16:08:43 +00:00
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2012-11-05 09:56:00 +00:00
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#include <linux/iio/trigger_consumer.h>
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#include <linux/iio/triggered_buffer.h>
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2010-11-22 13:35:32 +00:00
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2012-11-05 09:56:00 +00:00
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#include <linux/platform_data/ad7887.h>
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2010-11-22 13:35:32 +00:00
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2014-12-06 06:00:00 +00:00
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#define AD7887_REF_DIS BIT(5) /* on-chip reference disable */
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#define AD7887_DUAL BIT(4) /* dual-channel mode */
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#define AD7887_CH_AIN1 BIT(3) /* convert on channel 1, DUAL=1 */
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#define AD7887_CH_AIN0 0 /* 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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2012-11-05 09:56:00 +00:00
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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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/**
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* struct ad7887_chip_info - chip specifc information
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* @int_vref_mv: the internal reference voltage
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2019-11-25 13:21:37 +00:00
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* @channels: channels specification
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* @num_channels: number of channels
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* @dual_channels: channels specification in dual mode
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* @num_dual_channels: number of channels in dual mode
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2012-11-05 09:56:00 +00:00
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*/
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struct ad7887_chip_info {
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u16 int_vref_mv;
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2019-11-25 13:21:37 +00:00
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const struct iio_chan_spec *channels;
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unsigned int num_channels;
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const struct iio_chan_spec *dual_channels;
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unsigned int num_dual_channels;
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2012-11-05 09:56:00 +00:00
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};
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struct ad7887_state {
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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 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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2012-11-05 09:56:00 +00:00
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unsigned char tx_cmd_buf[4];
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2012-11-05 09:56:00 +00:00
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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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* Buffer needs to be large enough to hold two 16 bit samples and a
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* 64 bit aligned 64 bit timestamp.
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*/
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unsigned char data[ALIGN(4, sizeof(s64)) + sizeof(s64)]
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____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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static int ad7887_ring_preenable(struct iio_dev *indio_dev)
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{
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struct ad7887_state *st = iio_priv(indio_dev);
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/* We know this is a single long so can 'cheat' */
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switch (*indio_dev->active_scan_mask) {
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case (1 << 0):
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st->ring_msg = &st->msg[AD7887_CH0];
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break;
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case (1 << 1):
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st->ring_msg = &st->msg[AD7887_CH1];
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/* Dummy read: push CH1 setting down to hardware */
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spi_sync(st->spi, st->ring_msg);
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break;
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case ((1 << 1) | (1 << 0)):
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st->ring_msg = &st->msg[AD7887_CH0_CH1];
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break;
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}
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return 0;
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}
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static int ad7887_ring_postdisable(struct iio_dev *indio_dev)
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{
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struct ad7887_state *st = iio_priv(indio_dev);
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/* dummy read: restore default CH0 settin */
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return spi_sync(st->spi, &st->msg[AD7887_CH0]);
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}
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static irqreturn_t ad7887_trigger_handler(int irq, void *p)
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{
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struct iio_poll_func *pf = p;
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struct iio_dev *indio_dev = pf->indio_dev;
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struct ad7887_state *st = iio_priv(indio_dev);
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int b_sent;
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b_sent = spi_sync(st->spi, st->ring_msg);
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if (b_sent)
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goto done;
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2013-09-19 12:59:00 +00:00
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iio_push_to_buffers_with_timestamp(indio_dev, st->data,
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2016-03-09 18:05:49 +00:00
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iio_get_time_ns(indio_dev));
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2012-11-05 09:56:00 +00:00
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done:
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iio_trigger_notify_done(indio_dev->trig);
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return IRQ_HANDLED;
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}
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static const struct iio_buffer_setup_ops ad7887_ring_setup_ops = {
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.preenable = &ad7887_ring_preenable,
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.postdisable = &ad7887_ring_postdisable,
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};
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2010-11-22 13:35:32 +00:00
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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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2011-10-06 16:14:37 +00:00
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static int ad7887_read_raw(struct iio_dev *indio_dev,
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2011-05-18 13:41:50 +00:00
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struct iio_chan_spec const *chan,
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int *val,
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int *val2,
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long m)
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2010-11-22 13:35:32 +00:00
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{
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int ret;
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2011-10-06 16:14:37 +00:00
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struct ad7887_state *st = iio_priv(indio_dev);
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2010-11-22 13:35:32 +00:00
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2011-05-18 13:41:50 +00:00
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switch (m) {
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2012-04-15 16:41:18 +00:00
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case IIO_CHAN_INFO_RAW:
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2016-05-24 19:18:43 +00:00
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ret = iio_device_claim_direct_mode(indio_dev);
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if (ret)
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return ret;
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ret = ad7887_scan_direct(st, chan->address);
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iio_device_release_direct_mode(indio_dev);
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2011-05-18 13:41:50 +00:00
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if (ret < 0)
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return ret;
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2012-11-05 09:56:00 +00:00
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*val = ret >> chan->scan_type.shift;
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2014-12-06 06:00:00 +00:00
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*val &= GENMASK(chan->scan_type.realbits - 1, 0);
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2011-05-18 13:41:50 +00:00
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return IIO_VAL_INT;
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2011-10-26 16:41:36 +00:00
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case IIO_CHAN_INFO_SCALE:
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2012-11-05 09:56:00 +00:00
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if (st->reg) {
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*val = regulator_get_voltage(st->reg);
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if (*val < 0)
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return *val;
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*val /= 1000;
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} else {
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*val = st->chip_info->int_vref_mv;
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}
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2012-11-05 09:56:00 +00:00
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*val2 = chan->scan_type.realbits;
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2012-11-05 09:56:00 +00:00
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return IIO_VAL_FRACTIONAL_LOG2;
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2011-05-18 13:41:50 +00:00
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}
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return -EINVAL;
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2010-11-22 13:35:32 +00:00
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}
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2019-11-25 13:21:37 +00:00
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#define AD7887_CHANNEL(x) { \
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.type = IIO_VOLTAGE, \
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.indexed = 1, \
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.channel = (x), \
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.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
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.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
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.address = (x), \
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.scan_index = (x), \
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.scan_type = { \
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.sign = 'u', \
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.realbits = 12, \
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.storagebits = 16, \
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.shift = 0, \
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.endianness = IIO_BE, \
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}, \
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}
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static const struct iio_chan_spec ad7887_channels[] = {
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AD7887_CHANNEL(0),
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IIO_CHAN_SOFT_TIMESTAMP(1),
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};
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static const struct iio_chan_spec ad7887_dual_channels[] = {
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AD7887_CHANNEL(0),
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AD7887_CHANNEL(1),
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IIO_CHAN_SOFT_TIMESTAMP(2),
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};
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2010-11-22 13:35:32 +00:00
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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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2019-11-25 13:21:37 +00:00
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.channels = ad7887_channels,
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.num_channels = ARRAY_SIZE(ad7887_channels),
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.dual_channels = ad7887_dual_channels,
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.num_dual_channels = ARRAY_SIZE(ad7887_dual_channels),
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2010-11-22 13:35:32 +00:00
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.int_vref_mv = 2500,
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},
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};
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2011-05-18 13:42:37 +00:00
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static const struct iio_info ad7887_info = {
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.read_raw = &ad7887_read_raw,
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};
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2020-11-13 09:16:48 +00:00
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static void ad7887_reg_disable(void *data)
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{
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struct regulator *reg = data;
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regulator_disable(reg);
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}
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2012-12-21 21:21:43 +00:00
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static int ad7887_probe(struct spi_device *spi)
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2010-11-22 13:35:32 +00:00
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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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2013-07-23 08:58:00 +00:00
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struct iio_dev *indio_dev;
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2012-11-05 09:56:00 +00:00
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uint8_t mode;
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2012-11-05 09:56:00 +00:00
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int ret;
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2010-11-22 13:35:32 +00:00
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2013-07-23 08:58:00 +00:00
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indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
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2011-05-18 13:41:51 +00:00
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if (indio_dev == NULL)
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return -ENOMEM;
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st = iio_priv(indio_dev);
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2010-11-22 13:35:32 +00:00
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2020-10-02 08:27:23 +00:00
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st->reg = devm_regulator_get_optional(&spi->dev, "vref");
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if (IS_ERR(st->reg)) {
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if (PTR_ERR(st->reg) != -ENODEV)
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2013-07-23 08:58:00 +00:00
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return PTR_ERR(st->reg);
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2012-11-05 09:56:00 +00:00
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2020-10-02 08:27:23 +00:00
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st->reg = NULL;
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}
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if (st->reg) {
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2010-11-22 13:35:32 +00:00
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ret = regulator_enable(st->reg);
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if (ret)
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2013-07-23 08:58:00 +00:00
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return ret;
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2020-11-13 09:16:48 +00:00
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ret = devm_add_action_or_reset(&spi->dev, ad7887_reg_disable, st->reg);
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if (ret)
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return ret;
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2010-11-22 13:35:32 +00:00
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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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st->spi = spi;
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2011-05-18 13:41:51 +00:00
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indio_dev->name = spi_get_device_id(spi)->name;
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2011-05-18 13:42:37 +00:00
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indio_dev->info = &ad7887_info;
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2011-05-18 13:41:51 +00:00
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indio_dev->modes = INDIO_DIRECT_MODE;
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2010-11-22 13:35:32 +00:00
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/* Setup default message */
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2012-11-05 09:56:00 +00:00
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mode = AD7887_PM_MODE4;
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2020-10-02 08:27:23 +00:00
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if (!st->reg)
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2012-11-05 09:56:00 +00:00
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mode |= AD7887_REF_DIS;
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if (pdata && pdata->en_dual)
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mode |= AD7887_DUAL;
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st->tx_cmd_buf[0] = AD7887_CH_AIN0 | mode;
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2010-11-22 13:35:32 +00:00
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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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2012-11-05 09:56:00 +00:00
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st->tx_cmd_buf[2] = AD7887_CH_AIN1 | mode;
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2010-11-22 13:35:32 +00:00
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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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2012-11-05 09:56:00 +00:00
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st->xfer[2].tx_buf = &st->tx_cmd_buf[0];
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2010-11-22 13:35:32 +00:00
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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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2012-11-05 09:56:00 +00:00
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st->xfer[3].rx_buf = &st->data[2];
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st->xfer[3].tx_buf = &st->tx_cmd_buf[2];
|
2010-11-22 13:35:32 +00:00
|
|
|
st->xfer[3].len = 2;
|
|
|
|
|
|
|
|
spi_message_init(&st->msg[AD7887_CH1]);
|
|
|
|
spi_message_add_tail(&st->xfer[3], &st->msg[AD7887_CH1]);
|
|
|
|
|
2019-11-25 13:21:37 +00:00
|
|
|
indio_dev->channels = st->chip_info->dual_channels;
|
|
|
|
indio_dev->num_channels = st->chip_info->num_dual_channels;
|
2010-11-22 13:35:32 +00:00
|
|
|
} else {
|
2019-11-25 13:21:37 +00:00
|
|
|
indio_dev->channels = st->chip_info->channels;
|
|
|
|
indio_dev->num_channels = st->chip_info->num_channels;
|
2011-05-18 13:41:50 +00:00
|
|
|
}
|
2010-11-22 13:35:32 +00:00
|
|
|
|
2020-11-13 09:16:48 +00:00
|
|
|
ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev,
|
|
|
|
&iio_pollfunc_store_time,
|
2012-11-05 09:56:00 +00:00
|
|
|
&ad7887_trigger_handler, &ad7887_ring_setup_ops);
|
2010-11-22 13:35:32 +00:00
|
|
|
if (ret)
|
2020-11-13 09:16:48 +00:00
|
|
|
return ret;
|
2011-05-18 13:41:51 +00:00
|
|
|
|
2020-11-13 09:16:48 +00:00
|
|
|
return devm_iio_device_register(&spi->dev, indio_dev);
|
2010-11-22 13:35:32 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
static const struct spi_device_id ad7887_id[] = {
|
|
|
|
{"ad7887", ID_AD7887},
|
|
|
|
{}
|
|
|
|
};
|
2011-11-16 07:53:31 +00:00
|
|
|
MODULE_DEVICE_TABLE(spi, ad7887_id);
|
2010-11-22 13:35:32 +00:00
|
|
|
|
|
|
|
static struct spi_driver ad7887_driver = {
|
|
|
|
.driver = {
|
|
|
|
.name = "ad7887",
|
|
|
|
},
|
|
|
|
.probe = ad7887_probe,
|
|
|
|
.id_table = ad7887_id,
|
|
|
|
};
|
2011-11-16 09:13:39 +00:00
|
|
|
module_spi_driver(ad7887_driver);
|
2010-11-22 13:35:32 +00:00
|
|
|
|
2018-08-14 11:23:17 +00:00
|
|
|
MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
|
2010-11-22 13:35:32 +00:00
|
|
|
MODULE_DESCRIPTION("Analog Devices AD7887 ADC");
|
|
|
|
MODULE_LICENSE("GPL v2");
|