forked from Minki/linux
ae47d009b5
Maxim's max12xx series is very similar to the max10xx series, with the difference of the measurements depth which is upgraded from 10 to 12 bits per channel. Everything else looks the same. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
527 lines
13 KiB
C
527 lines
13 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* iio/adc/max1027.c
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* Copyright (C) 2014 Philippe Reynes
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*
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* based on linux/drivers/iio/ad7923.c
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* Copyright 2011 Analog Devices Inc (from AD7923 Driver)
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* Copyright 2012 CS Systemes d'Information
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*
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* max1027.c
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*
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* Partial support for max1027 and similar chips.
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*/
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/spi/spi.h>
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#include <linux/delay.h>
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#include <linux/iio/iio.h>
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#include <linux/iio/buffer.h>
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#include <linux/iio/trigger.h>
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#include <linux/iio/trigger_consumer.h>
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#include <linux/iio/triggered_buffer.h>
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#define MAX1027_CONV_REG BIT(7)
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#define MAX1027_SETUP_REG BIT(6)
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#define MAX1027_AVG_REG BIT(5)
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#define MAX1027_RST_REG BIT(4)
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/* conversion register */
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#define MAX1027_TEMP BIT(0)
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#define MAX1027_SCAN_0_N (0x00 << 1)
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#define MAX1027_SCAN_N_M (0x01 << 1)
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#define MAX1027_SCAN_N (0x02 << 1)
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#define MAX1027_NOSCAN (0x03 << 1)
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#define MAX1027_CHAN(n) ((n) << 3)
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/* setup register */
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#define MAX1027_UNIPOLAR 0x02
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#define MAX1027_BIPOLAR 0x03
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#define MAX1027_REF_MODE0 (0x00 << 2)
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#define MAX1027_REF_MODE1 (0x01 << 2)
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#define MAX1027_REF_MODE2 (0x02 << 2)
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#define MAX1027_REF_MODE3 (0x03 << 2)
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#define MAX1027_CKS_MODE0 (0x00 << 4)
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#define MAX1027_CKS_MODE1 (0x01 << 4)
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#define MAX1027_CKS_MODE2 (0x02 << 4)
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#define MAX1027_CKS_MODE3 (0x03 << 4)
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/* averaging register */
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#define MAX1027_NSCAN_4 0x00
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#define MAX1027_NSCAN_8 0x01
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#define MAX1027_NSCAN_12 0x02
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#define MAX1027_NSCAN_16 0x03
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#define MAX1027_NAVG_4 (0x00 << 2)
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#define MAX1027_NAVG_8 (0x01 << 2)
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#define MAX1027_NAVG_16 (0x02 << 2)
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#define MAX1027_NAVG_32 (0x03 << 2)
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#define MAX1027_AVG_EN BIT(4)
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enum max1027_id {
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max1027,
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max1029,
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max1031,
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max1227,
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max1229,
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max1231,
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};
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static const struct spi_device_id max1027_id[] = {
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{"max1027", max1027},
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{"max1029", max1029},
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{"max1031", max1031},
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{"max1227", max1227},
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{"max1229", max1229},
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{"max1231", max1231},
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{}
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};
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MODULE_DEVICE_TABLE(spi, max1027_id);
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#ifdef CONFIG_OF
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static const struct of_device_id max1027_adc_dt_ids[] = {
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{ .compatible = "maxim,max1027" },
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{ .compatible = "maxim,max1029" },
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{ .compatible = "maxim,max1031" },
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{ .compatible = "maxim,max1227" },
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{ .compatible = "maxim,max1229" },
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{ .compatible = "maxim,max1231" },
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{},
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};
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MODULE_DEVICE_TABLE(of, max1027_adc_dt_ids);
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#endif
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#define MAX1027_V_CHAN(index, depth) \
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{ \
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.type = IIO_VOLTAGE, \
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.indexed = 1, \
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.channel = index, \
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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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.scan_index = index + 1, \
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.scan_type = { \
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.sign = 'u', \
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.realbits = depth, \
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.storagebits = 16, \
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.shift = 2, \
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.endianness = IIO_BE, \
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}, \
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}
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#define MAX1027_T_CHAN \
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{ \
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.type = IIO_TEMP, \
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.channel = 0, \
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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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.scan_index = 0, \
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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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.endianness = IIO_BE, \
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}, \
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}
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#define MAX1X27_CHANNELS(depth) \
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MAX1027_T_CHAN, \
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MAX1027_V_CHAN(0, depth), \
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MAX1027_V_CHAN(1, depth), \
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MAX1027_V_CHAN(2, depth), \
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MAX1027_V_CHAN(3, depth), \
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MAX1027_V_CHAN(4, depth), \
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MAX1027_V_CHAN(5, depth), \
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MAX1027_V_CHAN(6, depth), \
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MAX1027_V_CHAN(7, depth)
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#define MAX1X29_CHANNELS(depth) \
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MAX1X27_CHANNELS(depth), \
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MAX1027_V_CHAN(8, depth), \
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MAX1027_V_CHAN(9, depth), \
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MAX1027_V_CHAN(10, depth), \
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MAX1027_V_CHAN(11, depth)
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#define MAX1X31_CHANNELS(depth) \
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MAX1X27_CHANNELS(depth), \
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MAX1X29_CHANNELS(depth), \
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MAX1027_V_CHAN(12, depth), \
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MAX1027_V_CHAN(13, depth), \
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MAX1027_V_CHAN(14, depth), \
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MAX1027_V_CHAN(15, depth)
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static const struct iio_chan_spec max1027_channels[] = {
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MAX1X27_CHANNELS(10),
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};
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static const struct iio_chan_spec max1029_channels[] = {
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MAX1X29_CHANNELS(10),
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};
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static const struct iio_chan_spec max1031_channels[] = {
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MAX1X31_CHANNELS(10),
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};
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static const struct iio_chan_spec max1227_channels[] = {
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MAX1X27_CHANNELS(12),
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};
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static const struct iio_chan_spec max1229_channels[] = {
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MAX1X29_CHANNELS(12),
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};
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static const struct iio_chan_spec max1231_channels[] = {
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MAX1X31_CHANNELS(12),
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};
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static const unsigned long max1027_available_scan_masks[] = {
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0x000001ff,
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0x00000000,
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};
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static const unsigned long max1029_available_scan_masks[] = {
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0x00001fff,
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0x00000000,
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};
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static const unsigned long max1031_available_scan_masks[] = {
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0x0001ffff,
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0x00000000,
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};
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struct max1027_chip_info {
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const struct iio_chan_spec *channels;
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unsigned int num_channels;
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const unsigned long *available_scan_masks;
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};
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static const struct max1027_chip_info max1027_chip_info_tbl[] = {
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[max1027] = {
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.channels = max1027_channels,
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.num_channels = ARRAY_SIZE(max1027_channels),
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.available_scan_masks = max1027_available_scan_masks,
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},
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[max1029] = {
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.channels = max1029_channels,
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.num_channels = ARRAY_SIZE(max1029_channels),
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.available_scan_masks = max1029_available_scan_masks,
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},
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[max1031] = {
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.channels = max1031_channels,
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.num_channels = ARRAY_SIZE(max1031_channels),
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.available_scan_masks = max1031_available_scan_masks,
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},
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[max1227] = {
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.channels = max1227_channels,
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.num_channels = ARRAY_SIZE(max1227_channels),
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.available_scan_masks = max1027_available_scan_masks,
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},
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[max1229] = {
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.channels = max1229_channels,
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.num_channels = ARRAY_SIZE(max1229_channels),
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.available_scan_masks = max1029_available_scan_masks,
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},
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[max1231] = {
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.channels = max1231_channels,
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.num_channels = ARRAY_SIZE(max1231_channels),
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.available_scan_masks = max1031_available_scan_masks,
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},
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};
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struct max1027_state {
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const struct max1027_chip_info *info;
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struct spi_device *spi;
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struct iio_trigger *trig;
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__be16 *buffer;
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struct mutex lock;
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u8 reg ____cacheline_aligned;
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};
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static int max1027_read_single_value(struct iio_dev *indio_dev,
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struct iio_chan_spec const *chan,
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int *val)
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{
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int ret;
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struct max1027_state *st = iio_priv(indio_dev);
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if (iio_buffer_enabled(indio_dev)) {
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dev_warn(&indio_dev->dev, "trigger mode already enabled");
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return -EBUSY;
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}
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/* Start acquisition on conversion register write */
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st->reg = MAX1027_SETUP_REG | MAX1027_REF_MODE2 | MAX1027_CKS_MODE2;
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ret = spi_write(st->spi, &st->reg, 1);
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if (ret < 0) {
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dev_err(&indio_dev->dev,
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"Failed to configure setup register\n");
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return ret;
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}
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/* Configure conversion register with the requested chan */
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st->reg = MAX1027_CONV_REG | MAX1027_CHAN(chan->channel) |
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MAX1027_NOSCAN;
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if (chan->type == IIO_TEMP)
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st->reg |= MAX1027_TEMP;
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ret = spi_write(st->spi, &st->reg, 1);
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if (ret < 0) {
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dev_err(&indio_dev->dev,
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"Failed to configure conversion register\n");
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return ret;
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}
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/*
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* For an unknown reason, when we use the mode "10" (write
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* conversion register), the interrupt doesn't occur every time.
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* So we just wait 1 ms.
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*/
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mdelay(1);
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/* Read result */
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ret = spi_read(st->spi, st->buffer, (chan->type == IIO_TEMP) ? 4 : 2);
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if (ret < 0)
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return ret;
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*val = be16_to_cpu(st->buffer[0]);
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return IIO_VAL_INT;
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}
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static int max1027_read_raw(struct iio_dev *indio_dev,
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struct iio_chan_spec const *chan,
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int *val, int *val2, long mask)
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{
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int ret = 0;
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struct max1027_state *st = iio_priv(indio_dev);
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mutex_lock(&st->lock);
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switch (mask) {
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case IIO_CHAN_INFO_RAW:
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ret = max1027_read_single_value(indio_dev, chan, val);
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break;
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case IIO_CHAN_INFO_SCALE:
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switch (chan->type) {
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case IIO_TEMP:
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*val = 1;
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*val2 = 8;
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ret = IIO_VAL_FRACTIONAL;
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break;
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case IIO_VOLTAGE:
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*val = 2500;
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*val2 = chan->scan_type.realbits;
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ret = IIO_VAL_FRACTIONAL_LOG2;
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break;
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default:
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ret = -EINVAL;
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break;
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}
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break;
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default:
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ret = -EINVAL;
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break;
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}
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mutex_unlock(&st->lock);
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return ret;
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}
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static int max1027_debugfs_reg_access(struct iio_dev *indio_dev,
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unsigned reg, unsigned writeval,
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unsigned *readval)
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{
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struct max1027_state *st = iio_priv(indio_dev);
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u8 *val = (u8 *)st->buffer;
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if (readval) {
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int ret = spi_read(st->spi, val, 2);
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*readval = be16_to_cpu(st->buffer[0]);
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return ret;
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}
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*val = (u8)writeval;
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return spi_write(st->spi, val, 1);
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}
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static int max1027_validate_trigger(struct iio_dev *indio_dev,
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struct iio_trigger *trig)
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{
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struct max1027_state *st = iio_priv(indio_dev);
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if (st->trig != trig)
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return -EINVAL;
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return 0;
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}
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static int max1027_set_trigger_state(struct iio_trigger *trig, bool state)
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{
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struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
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struct max1027_state *st = iio_priv(indio_dev);
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int ret;
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if (state) {
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/* Start acquisition on cnvst */
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st->reg = MAX1027_SETUP_REG | MAX1027_CKS_MODE0 |
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MAX1027_REF_MODE2;
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ret = spi_write(st->spi, &st->reg, 1);
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if (ret < 0)
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return ret;
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/* Scan from 0 to max */
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st->reg = MAX1027_CONV_REG | MAX1027_CHAN(0) |
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MAX1027_SCAN_N_M | MAX1027_TEMP;
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ret = spi_write(st->spi, &st->reg, 1);
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if (ret < 0)
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return ret;
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} else {
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/* Start acquisition on conversion register write */
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st->reg = MAX1027_SETUP_REG | MAX1027_CKS_MODE2 |
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MAX1027_REF_MODE2;
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ret = spi_write(st->spi, &st->reg, 1);
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if (ret < 0)
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return ret;
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}
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return 0;
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}
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static irqreturn_t max1027_trigger_handler(int irq, void *private)
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{
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struct iio_poll_func *pf = private;
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struct iio_dev *indio_dev = pf->indio_dev;
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struct max1027_state *st = iio_priv(indio_dev);
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pr_debug("%s(irq=%d, private=0x%p)\n", __func__, irq, private);
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/* fill buffer with all channel */
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spi_read(st->spi, st->buffer, indio_dev->masklength * 2);
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iio_push_to_buffers(indio_dev, st->buffer);
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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_trigger_ops max1027_trigger_ops = {
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.validate_device = &iio_trigger_validate_own_device,
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.set_trigger_state = &max1027_set_trigger_state,
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};
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static const struct iio_info max1027_info = {
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.read_raw = &max1027_read_raw,
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.validate_trigger = &max1027_validate_trigger,
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.debugfs_reg_access = &max1027_debugfs_reg_access,
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};
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static int max1027_probe(struct spi_device *spi)
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{
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int ret;
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struct iio_dev *indio_dev;
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struct max1027_state *st;
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pr_debug("%s: probe(spi = 0x%p)\n", __func__, spi);
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indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
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if (indio_dev == NULL) {
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pr_err("Can't allocate iio device\n");
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return -ENOMEM;
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}
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spi_set_drvdata(spi, indio_dev);
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st = iio_priv(indio_dev);
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st->spi = spi;
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st->info = &max1027_chip_info_tbl[spi_get_device_id(spi)->driver_data];
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mutex_init(&st->lock);
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indio_dev->name = spi_get_device_id(spi)->name;
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indio_dev->dev.parent = &spi->dev;
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indio_dev->dev.of_node = spi->dev.of_node;
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indio_dev->info = &max1027_info;
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indio_dev->modes = INDIO_DIRECT_MODE;
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indio_dev->channels = st->info->channels;
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indio_dev->num_channels = st->info->num_channels;
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indio_dev->available_scan_masks = st->info->available_scan_masks;
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st->buffer = devm_kmalloc_array(&indio_dev->dev,
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indio_dev->num_channels, 2,
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GFP_KERNEL);
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if (st->buffer == NULL) {
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dev_err(&indio_dev->dev, "Can't allocate buffer\n");
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return -ENOMEM;
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}
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if (spi->irq) {
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ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev,
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&iio_pollfunc_store_time,
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&max1027_trigger_handler,
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NULL);
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if (ret < 0) {
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dev_err(&indio_dev->dev, "Failed to setup buffer\n");
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return ret;
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}
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st->trig = devm_iio_trigger_alloc(&spi->dev, "%s-trigger",
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indio_dev->name);
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if (st->trig == NULL) {
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ret = -ENOMEM;
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dev_err(&indio_dev->dev,
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"Failed to allocate iio trigger\n");
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return ret;
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}
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st->trig->ops = &max1027_trigger_ops;
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st->trig->dev.parent = &spi->dev;
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iio_trigger_set_drvdata(st->trig, indio_dev);
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iio_trigger_register(st->trig);
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ret = devm_request_threaded_irq(&spi->dev, spi->irq,
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iio_trigger_generic_data_rdy_poll,
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NULL,
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IRQF_TRIGGER_FALLING,
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spi->dev.driver->name,
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st->trig);
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if (ret < 0) {
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dev_err(&indio_dev->dev, "Failed to allocate IRQ.\n");
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
/* Internal reset */
|
|
st->reg = MAX1027_RST_REG;
|
|
ret = spi_write(st->spi, &st->reg, 1);
|
|
if (ret < 0) {
|
|
dev_err(&indio_dev->dev, "Failed to reset the ADC\n");
|
|
return ret;
|
|
}
|
|
|
|
/* Disable averaging */
|
|
st->reg = MAX1027_AVG_REG;
|
|
ret = spi_write(st->spi, &st->reg, 1);
|
|
if (ret < 0) {
|
|
dev_err(&indio_dev->dev, "Failed to configure averaging register\n");
|
|
return ret;
|
|
}
|
|
|
|
return devm_iio_device_register(&spi->dev, indio_dev);
|
|
}
|
|
|
|
static struct spi_driver max1027_driver = {
|
|
.driver = {
|
|
.name = "max1027",
|
|
.of_match_table = of_match_ptr(max1027_adc_dt_ids),
|
|
},
|
|
.probe = max1027_probe,
|
|
.id_table = max1027_id,
|
|
};
|
|
module_spi_driver(max1027_driver);
|
|
|
|
MODULE_AUTHOR("Philippe Reynes <tremyfr@yahoo.fr>");
|
|
MODULE_DESCRIPTION("MAX1X27/MAX1X29/MAX1X31 ADC");
|
|
MODULE_LICENSE("GPL v2");
|