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linux/drivers/iio/adc/ad7923.c
Jonathan Cameron 09e3bdfe49 iio: adc: standardize on formatting for id match tables 
This is a frequent minor comment in reviews, so start cleaning up
existing drivers in the hope we get fewer cases of cut and paste.

There are not kernel wide rules for these, but for IIO the style
that I prefer (and hence most common) is:

- Space after { and before }
- No comma after terminator { }

This may cause merge conflicts but they should be trivial to resolve
hence I have not broken this into per driver patches.

Link: https://patch.msgid.link/20240818180912.719399-1-jic23@kernel.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2024-09-05 19:27:13 +01:00

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// SPDX-License-Identifier: GPL-2.0-only
/*
* AD7904/AD7914/AD7923/AD7924/AD7908/AD7918/AD7928 SPI ADC driver
*
* Copyright 2011 Analog Devices Inc (from AD7923 Driver)
* Copyright 2012 CS Systemes d'Information
*/
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/property.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/spi/spi.h>
#include <linux/regulator/consumer.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/buffer.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#define AD7923_WRITE_CR BIT(11) /* write control register */
#define AD7923_RANGE BIT(1) /* range to REFin */
#define AD7923_CODING BIT(0) /* coding is straight binary */
#define AD7923_PM_MODE_AS (1) /* auto shutdown */
#define AD7923_PM_MODE_FS (2) /* full shutdown */
#define AD7923_PM_MODE_OPS (3) /* normal operation */
#define AD7923_SEQUENCE_OFF (0) /* no sequence fonction */
#define AD7923_SEQUENCE_PROTECT (2) /* no interrupt write cycle */
#define AD7923_SEQUENCE_ON (3) /* continuous sequence */
#define AD7923_PM_MODE_WRITE(mode) ((mode) << 4) /* write mode */
#define AD7923_CHANNEL_WRITE(channel) ((channel) << 6) /* write channel */
#define AD7923_SEQUENCE_WRITE(sequence) ((((sequence) & 1) << 3) \
+ (((sequence) & 2) << 9))
/* write sequence fonction */
/* left shift for CR : bit 11 transmit in first */
#define AD7923_SHIFT_REGISTER 4
/* val = value, dec = left shift, bits = number of bits of the mask */
#define EXTRACT(val, dec, bits) (((val) >> (dec)) & ((1 << (bits)) - 1))
struct ad7923_state {
struct spi_device *spi;
struct spi_transfer ring_xfer[5];
struct spi_transfer scan_single_xfer[2];
struct spi_message ring_msg;
struct spi_message scan_single_msg;
struct regulator *reg;
unsigned int settings;
/*
* DMA (thus cache coherency maintenance) may require the
* transfer buffers to live in their own cache lines.
* Ensure rx_buf can be directly used in iio_push_to_buffers_with_timetamp
* Length = 8 channels + 4 extra for 8 byte timestamp
*/
__be16 rx_buf[12] __aligned(IIO_DMA_MINALIGN);
__be16 tx_buf[4];
};
struct ad7923_chip_info {
const struct iio_chan_spec *channels;
unsigned int num_channels;
};
enum ad7923_id {
AD7904,
AD7914,
AD7924,
AD7908,
AD7918,
AD7928
};
#define AD7923_V_CHAN(index, bits) \
{ \
.type = IIO_VOLTAGE, \
.indexed = 1, \
.channel = index, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
.address = index, \
.scan_index = index, \
.scan_type = { \
.sign = 'u', \
.realbits = (bits), \
.storagebits = 16, \
.shift = 12 - (bits), \
.endianness = IIO_BE, \
}, \
}
#define DECLARE_AD7923_CHANNELS(name, bits) \
const struct iio_chan_spec name ## _channels[] = { \
AD7923_V_CHAN(0, bits), \
AD7923_V_CHAN(1, bits), \
AD7923_V_CHAN(2, bits), \
AD7923_V_CHAN(3, bits), \
IIO_CHAN_SOFT_TIMESTAMP(4), \
}
#define DECLARE_AD7908_CHANNELS(name, bits) \
const struct iio_chan_spec name ## _channels[] = { \
AD7923_V_CHAN(0, bits), \
AD7923_V_CHAN(1, bits), \
AD7923_V_CHAN(2, bits), \
AD7923_V_CHAN(3, bits), \
AD7923_V_CHAN(4, bits), \
AD7923_V_CHAN(5, bits), \
AD7923_V_CHAN(6, bits), \
AD7923_V_CHAN(7, bits), \
IIO_CHAN_SOFT_TIMESTAMP(8), \
}
static DECLARE_AD7923_CHANNELS(ad7904, 8);
static DECLARE_AD7923_CHANNELS(ad7914, 10);
static DECLARE_AD7923_CHANNELS(ad7924, 12);
static DECLARE_AD7908_CHANNELS(ad7908, 8);
static DECLARE_AD7908_CHANNELS(ad7918, 10);
static DECLARE_AD7908_CHANNELS(ad7928, 12);
static const struct ad7923_chip_info ad7923_chip_info[] = {
[AD7904] = {
.channels = ad7904_channels,
.num_channels = ARRAY_SIZE(ad7904_channels),
},
[AD7914] = {
.channels = ad7914_channels,
.num_channels = ARRAY_SIZE(ad7914_channels),
},
[AD7924] = {
.channels = ad7924_channels,
.num_channels = ARRAY_SIZE(ad7924_channels),
},
[AD7908] = {
.channels = ad7908_channels,
.num_channels = ARRAY_SIZE(ad7908_channels),
},
[AD7918] = {
.channels = ad7918_channels,
.num_channels = ARRAY_SIZE(ad7918_channels),
},
[AD7928] = {
.channels = ad7928_channels,
.num_channels = ARRAY_SIZE(ad7928_channels),
},
};
/*
* ad7923_update_scan_mode() setup the spi transfer buffer for the new scan mask
*/
static int ad7923_update_scan_mode(struct iio_dev *indio_dev,
const unsigned long *active_scan_mask)
{
struct ad7923_state *st = iio_priv(indio_dev);
int i, cmd, len;
len = 0;
/*
* For this driver the last channel is always the software timestamp so
* skip that one.
*/
for_each_set_bit(i, active_scan_mask, indio_dev->num_channels - 1) {
cmd = AD7923_WRITE_CR | AD7923_CHANNEL_WRITE(i) |
AD7923_SEQUENCE_WRITE(AD7923_SEQUENCE_OFF) |
st->settings;
cmd <<= AD7923_SHIFT_REGISTER;
st->tx_buf[len++] = cpu_to_be16(cmd);
}
/* build spi ring message */
st->ring_xfer[0].tx_buf = &st->tx_buf[0];
st->ring_xfer[0].len = len;
st->ring_xfer[0].cs_change = 1;
spi_message_init(&st->ring_msg);
spi_message_add_tail(&st->ring_xfer[0], &st->ring_msg);
for (i = 0; i < len; i++) {
st->ring_xfer[i + 1].rx_buf = &st->rx_buf[i];
st->ring_xfer[i + 1].len = 2;
st->ring_xfer[i + 1].cs_change = 1;
spi_message_add_tail(&st->ring_xfer[i + 1], &st->ring_msg);
}
/* make sure last transfer cs_change is not set */
st->ring_xfer[i + 1].cs_change = 0;
return 0;
}
static irqreturn_t ad7923_trigger_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
struct ad7923_state *st = iio_priv(indio_dev);
int b_sent;
b_sent = spi_sync(st->spi, &st->ring_msg);
if (b_sent)
goto done;
iio_push_to_buffers_with_timestamp(indio_dev, st->rx_buf,
iio_get_time_ns(indio_dev));
done:
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
static int ad7923_scan_direct(struct ad7923_state *st, unsigned int ch)
{
int ret, cmd;
cmd = AD7923_WRITE_CR | AD7923_CHANNEL_WRITE(ch) |
AD7923_SEQUENCE_WRITE(AD7923_SEQUENCE_OFF) |
st->settings;
cmd <<= AD7923_SHIFT_REGISTER;
st->tx_buf[0] = cpu_to_be16(cmd);
ret = spi_sync(st->spi, &st->scan_single_msg);
if (ret)
return ret;
return be16_to_cpu(st->rx_buf[0]);
}
static int ad7923_get_range(struct ad7923_state *st)
{
int vref;
vref = regulator_get_voltage(st->reg);
if (vref < 0)
return vref;
vref /= 1000;
if (!(st->settings & AD7923_RANGE))
vref *= 2;
return vref;
}
static int ad7923_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val,
int *val2,
long m)
{
int ret;
struct ad7923_state *st = iio_priv(indio_dev);
switch (m) {
case IIO_CHAN_INFO_RAW:
ret = iio_device_claim_direct_mode(indio_dev);
if (ret)
return ret;
ret = ad7923_scan_direct(st, chan->address);
iio_device_release_direct_mode(indio_dev);
if (ret < 0)
return ret;
if (chan->address == EXTRACT(ret, 12, 4))
*val = EXTRACT(ret, chan->scan_type.shift,
chan->scan_type.realbits);
else
return -EIO;
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
ret = ad7923_get_range(st);
if (ret < 0)
return ret;
*val = ret;
*val2 = chan->scan_type.realbits;
return IIO_VAL_FRACTIONAL_LOG2;
}
return -EINVAL;
}
static const struct iio_info ad7923_info = {
.read_raw = &ad7923_read_raw,
.update_scan_mode = ad7923_update_scan_mode,
};
static void ad7923_regulator_disable(void *data)
{
struct ad7923_state *st = data;
regulator_disable(st->reg);
}
static int ad7923_probe(struct spi_device *spi)
{
u32 ad7923_range = AD7923_RANGE;
struct ad7923_state *st;
struct iio_dev *indio_dev;
const struct ad7923_chip_info *info;
int ret;
indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
if (!indio_dev)
return -ENOMEM;
st = iio_priv(indio_dev);
if (device_property_read_bool(&spi->dev, "adi,range-double"))
ad7923_range = 0;
st->spi = spi;
st->settings = AD7923_CODING | ad7923_range |
AD7923_PM_MODE_WRITE(AD7923_PM_MODE_OPS);
info = &ad7923_chip_info[spi_get_device_id(spi)->driver_data];
indio_dev->name = spi_get_device_id(spi)->name;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = info->channels;
indio_dev->num_channels = info->num_channels;
indio_dev->info = &ad7923_info;
/* Setup default message */
st->scan_single_xfer[0].tx_buf = &st->tx_buf[0];
st->scan_single_xfer[0].len = 2;
st->scan_single_xfer[0].cs_change = 1;
st->scan_single_xfer[1].rx_buf = &st->rx_buf[0];
st->scan_single_xfer[1].len = 2;
spi_message_init(&st->scan_single_msg);
spi_message_add_tail(&st->scan_single_xfer[0], &st->scan_single_msg);
spi_message_add_tail(&st->scan_single_xfer[1], &st->scan_single_msg);
st->reg = devm_regulator_get(&spi->dev, "refin");
if (IS_ERR(st->reg))
return PTR_ERR(st->reg);
ret = regulator_enable(st->reg);
if (ret)
return ret;
ret = devm_add_action_or_reset(&spi->dev, ad7923_regulator_disable, st);
if (ret)
return ret;
ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev, NULL,
&ad7923_trigger_handler, NULL);
if (ret)
return ret;
return devm_iio_device_register(&spi->dev, indio_dev);
}
static const struct spi_device_id ad7923_id[] = {
{ "ad7904", AD7904 },
{ "ad7914", AD7914 },
{ "ad7923", AD7924 },
{ "ad7924", AD7924 },
{ "ad7908", AD7908 },
{ "ad7918", AD7918 },
{ "ad7928", AD7928 },
{ }
};
MODULE_DEVICE_TABLE(spi, ad7923_id);
static const struct of_device_id ad7923_of_match[] = {
{ .compatible = "adi,ad7904", },
{ .compatible = "adi,ad7914", },
{ .compatible = "adi,ad7923", },
{ .compatible = "adi,ad7924", },
{ .compatible = "adi,ad7908", },
{ .compatible = "adi,ad7918", },
{ .compatible = "adi,ad7928", },
{ }
};
MODULE_DEVICE_TABLE(of, ad7923_of_match);
static struct spi_driver ad7923_driver = {
.driver = {
.name = "ad7923",
.of_match_table = ad7923_of_match,
},
.probe = ad7923_probe,
.id_table = ad7923_id,
};
module_spi_driver(ad7923_driver);
MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
MODULE_AUTHOR("Patrick Vasseur <patrick.vasseur@c-s.fr>");
MODULE_DESCRIPTION("Analog Devices AD7923 and similar ADC");
MODULE_LICENSE("GPL v2");
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