diff options
Diffstat (limited to 'drivers/iio/adc/max11410.c')
| -rw-r--r-- | drivers/iio/adc/max11410.c | 1050 |
1 files changed, 1050 insertions, 0 deletions
diff --git a/drivers/iio/adc/max11410.c b/drivers/iio/adc/max11410.c new file mode 100644 index 000000000000..fdc9f03135b5 --- /dev/null +++ b/drivers/iio/adc/max11410.c @@ -0,0 +1,1050 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * MAX11410 SPI ADC driver + * + * Copyright 2022 Analog Devices Inc. + */ +#include <asm-generic/unaligned.h> +#include <linux/bitfield.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/regmap.h> +#include <linux/regulator/consumer.h> +#include <linux/spi/spi.h> + +#include <linux/iio/buffer.h> +#include <linux/iio/sysfs.h> +#include <linux/iio/trigger.h> +#include <linux/iio/trigger_consumer.h> +#include <linux/iio/triggered_buffer.h> + +#define MAX11410_REG_CONV_START 0x01 +#define MAX11410_CONV_TYPE_SINGLE 0x00 +#define MAX11410_CONV_TYPE_CONTINUOUS 0x01 +#define MAX11410_REG_CAL_START 0x03 +#define MAX11410_CAL_START_SELF 0x00 +#define MAX11410_CAL_START_PGA 0x01 +#define MAX11410_REG_GPIO_CTRL(ch) ((ch) ? 0x05 : 0x04) +#define MAX11410_GPIO_INTRB 0xC1 +#define MAX11410_REG_FILTER 0x08 +#define MAX11410_FILTER_RATE_MASK GENMASK(3, 0) +#define MAX11410_FILTER_RATE_MAX 0x0F +#define MAX11410_FILTER_LINEF_MASK GENMASK(5, 4) +#define MAX11410_FILTER_50HZ BIT(5) +#define MAX11410_FILTER_60HZ BIT(4) +#define MAX11410_REG_CTRL 0x09 +#define MAX11410_CTRL_REFSEL_MASK GENMASK(2, 0) +#define MAX11410_CTRL_VREFN_BUF_BIT BIT(3) +#define MAX11410_CTRL_VREFP_BUF_BIT BIT(4) +#define MAX11410_CTRL_FORMAT_BIT BIT(5) +#define MAX11410_CTRL_UNIPOLAR_BIT BIT(6) +#define MAX11410_REG_MUX_CTRL0 0x0B +#define MAX11410_REG_PGA 0x0E +#define MAX11410_PGA_GAIN_MASK GENMASK(2, 0) +#define MAX11410_PGA_SIG_PATH_MASK GENMASK(5, 4) +#define MAX11410_PGA_SIG_PATH_BUFFERED 0x00 +#define MAX11410_PGA_SIG_PATH_BYPASS 0x01 +#define MAX11410_PGA_SIG_PATH_PGA 0x02 +#define MAX11410_REG_DATA0 0x30 +#define MAX11410_REG_STATUS 0x38 +#define MAX11410_STATUS_CONV_READY_BIT BIT(0) +#define MAX11410_STATUS_CAL_READY_BIT BIT(2) + +#define MAX11410_REFSEL_AVDD_AGND 0x03 +#define MAX11410_REFSEL_MAX 0x06 +#define MAX11410_SIG_PATH_MAX 0x02 +#define MAX11410_CHANNEL_INDEX_MAX 0x0A +#define MAX11410_AINP_AVDD 0x0A +#define MAX11410_AINN_GND 0x0A + +#define MAX11410_CONVERSION_TIMEOUT_MS 2000 +#define MAX11410_CALIB_TIMEOUT_MS 2000 + +#define MAX11410_SCALE_AVAIL_SIZE 8 + +enum max11410_filter { + MAX11410_FILTER_FIR5060, + MAX11410_FILTER_FIR50, + MAX11410_FILTER_FIR60, + MAX11410_FILTER_SINC4, +}; + +static const u8 max11410_sampling_len[] = { + [MAX11410_FILTER_FIR5060] = 5, + [MAX11410_FILTER_FIR50] = 6, + [MAX11410_FILTER_FIR60] = 6, + [MAX11410_FILTER_SINC4] = 10, +}; + +static const int max11410_sampling_rates[4][10][2] = { + [MAX11410_FILTER_FIR5060] = { + { 1, 100000 }, + { 2, 100000 }, + { 4, 200000 }, + { 8, 400000 }, + { 16, 800000 } + }, + [MAX11410_FILTER_FIR50] = { + { 1, 300000 }, + { 2, 700000 }, + { 5, 300000 }, + { 10, 700000 }, + { 21, 300000 }, + { 40 } + }, + [MAX11410_FILTER_FIR60] = { + { 1, 300000 }, + { 2, 700000 }, + { 5, 300000 }, + { 10, 700000 }, + { 21, 300000 }, + { 40 } + }, + [MAX11410_FILTER_SINC4] = { + { 4 }, + { 10 }, + { 20 }, + { 40 }, + { 60 }, + { 120 }, + { 240 }, + { 480 }, + { 960 }, + { 1920 } + } +}; + +struct max11410_channel_config { + u32 settling_time_us; + u32 *scale_avail; + u8 refsel; + u8 sig_path; + u8 gain; + bool bipolar; + bool buffered_vrefp; + bool buffered_vrefn; +}; + +struct max11410_state { + struct spi_device *spi_dev; + struct iio_trigger *trig; + struct completion completion; + struct mutex lock; /* Prevent changing channel config during sampling */ + struct regmap *regmap; + struct regulator *avdd; + struct regulator *vrefp[3]; + struct regulator *vrefn[3]; + struct max11410_channel_config *channels; + int irq; + struct { + u32 data __aligned(IIO_DMA_MINALIGN); + s64 ts __aligned(8); + } scan; +}; + +static const struct iio_chan_spec chanspec_template = { + .type = IIO_VOLTAGE, + .indexed = 1, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_OFFSET), + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), + .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), + .scan_type = { + .sign = 's', + .realbits = 24, + .storagebits = 32, + .endianness = IIO_LE, + }, +}; + +static unsigned int max11410_reg_size(unsigned int reg) +{ + /* Registers from 0x00 to 0x10 are 1 byte, the rest are 3 bytes long. */ + return reg <= 0x10 ? 1 : 3; +} + +static int max11410_write_reg(struct max11410_state *st, unsigned int reg, + unsigned int val) +{ + /* This driver only needs to write 8-bit registers */ + if (max11410_reg_size(reg) != 1) + return -EINVAL; + + return regmap_write(st->regmap, reg, val); +} + +static int max11410_read_reg(struct max11410_state *st, unsigned int reg, + int *val) +{ + int ret; + + if (max11410_reg_size(reg) == 3) { + ret = regmap_bulk_read(st->regmap, reg, &st->scan.data, 3); + if (ret) + return ret; + + *val = get_unaligned_be24(&st->scan.data); + return 0; + } + + return regmap_read(st->regmap, reg, val); +} + +static struct regulator *max11410_get_vrefp(struct max11410_state *st, + u8 refsel) +{ + refsel = refsel % 4; + if (refsel == 3) + return st->avdd; + + return st->vrefp[refsel]; +} + +static struct regulator *max11410_get_vrefn(struct max11410_state *st, + u8 refsel) +{ + if (refsel > 2) + return NULL; + + return st->vrefn[refsel]; +} + +static const struct regmap_config regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = 0x39, +}; + +static ssize_t max11410_notch_en_show(struct device *dev, + struct device_attribute *devattr, + char *buf) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct max11410_state *state = iio_priv(indio_dev); + struct iio_dev_attr *iio_attr = to_iio_dev_attr(devattr); + unsigned int val; + int ret; + + ret = max11410_read_reg(state, MAX11410_REG_FILTER, &val); + if (ret) + return ret; + + switch (iio_attr->address) { + case 0: + val = !FIELD_GET(MAX11410_FILTER_50HZ, val); + break; + case 1: + val = !FIELD_GET(MAX11410_FILTER_60HZ, val); + break; + case 2: + val = FIELD_GET(MAX11410_FILTER_LINEF_MASK, val) == 3; + break; + default: + return -EINVAL; + } + + return sysfs_emit(buf, "%d\n", val); +} + +static ssize_t max11410_notch_en_store(struct device *dev, + struct device_attribute *devattr, + const char *buf, size_t count) +{ + struct iio_dev_attr *iio_attr = to_iio_dev_attr(devattr); + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct max11410_state *state = iio_priv(indio_dev); + unsigned int filter_bits; + bool enable; + int ret; + + ret = kstrtobool(buf, &enable); + if (ret) + return ret; + + switch (iio_attr->address) { + case 0: + filter_bits = MAX11410_FILTER_50HZ; + break; + case 1: + filter_bits = MAX11410_FILTER_60HZ; + break; + case 2: + default: + filter_bits = MAX11410_FILTER_50HZ | MAX11410_FILTER_60HZ; + enable = !enable; + break; + } + + if (enable) + ret = regmap_clear_bits(state->regmap, MAX11410_REG_FILTER, + filter_bits); + else + ret = regmap_set_bits(state->regmap, MAX11410_REG_FILTER, + filter_bits); + + if (ret) + return ret; + + return count; +} + +static ssize_t in_voltage_filter2_notch_center_show(struct device *dev, + struct device_attribute *devattr, + char *buf) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct max11410_state *state = iio_priv(indio_dev); + int ret, reg, rate, filter; + + ret = regmap_read(state->regmap, MAX11410_REG_FILTER, ®); + if (ret) + return ret; + + rate = FIELD_GET(MAX11410_FILTER_RATE_MASK, reg); + rate = clamp_val(rate, 0, + max11410_sampling_len[MAX11410_FILTER_SINC4] - 1); + filter = max11410_sampling_rates[MAX11410_FILTER_SINC4][rate][0]; + + return sysfs_emit(buf, "%d\n", filter); +} + +static IIO_CONST_ATTR(in_voltage_filter0_notch_center, "50"); +static IIO_CONST_ATTR(in_voltage_filter1_notch_center, "60"); +static IIO_DEVICE_ATTR_RO(in_voltage_filter2_notch_center, 2); + +static IIO_DEVICE_ATTR(in_voltage_filter0_notch_en, 0644, + max11410_notch_en_show, max11410_notch_en_store, 0); +static IIO_DEVICE_ATTR(in_voltage_filter1_notch_en, 0644, + max11410_notch_en_show, max11410_notch_en_store, 1); +static IIO_DEVICE_ATTR(in_voltage_filter2_notch_en, 0644, + max11410_notch_en_show, max11410_notch_en_store, 2); + +static struct attribute *max11410_attributes[] = { + &iio_const_attr_in_voltage_filter0_notch_center.dev_attr.attr, + &iio_const_attr_in_voltage_filter1_notch_center.dev_attr.attr, + &iio_dev_attr_in_voltage_filter2_notch_center.dev_attr.attr, + &iio_dev_attr_in_voltage_filter0_notch_en.dev_attr.attr, + &iio_dev_attr_in_voltage_filter1_notch_en.dev_attr.attr, + &iio_dev_attr_in_voltage_filter2_notch_en.dev_attr.attr, + NULL +}; + +static const struct attribute_group max11410_attribute_group = { + .attrs = max11410_attributes, +}; + +static int max11410_set_input_mux(struct max11410_state *st, u8 ainp, u8 ainn) +{ + if (ainp > MAX11410_CHANNEL_INDEX_MAX || + ainn > MAX11410_CHANNEL_INDEX_MAX) + return -EINVAL; + + return max11410_write_reg(st, MAX11410_REG_MUX_CTRL0, + (ainp << 4) | ainn); +} + +static int max11410_configure_channel(struct max11410_state *st, + struct iio_chan_spec const *chan) +{ + struct max11410_channel_config cfg = st->channels[chan->address]; + unsigned int regval; + int ret; + + if (chan->differential) + ret = max11410_set_input_mux(st, chan->channel, chan->channel2); + else + ret = max11410_set_input_mux(st, chan->channel, + MAX11410_AINN_GND); + + if (ret) + return ret; + + regval = FIELD_PREP(MAX11410_CTRL_VREFP_BUF_BIT, cfg.buffered_vrefp) | + FIELD_PREP(MAX11410_CTRL_VREFN_BUF_BIT, cfg.buffered_vrefn) | + FIELD_PREP(MAX11410_CTRL_REFSEL_MASK, cfg.refsel) | + FIELD_PREP(MAX11410_CTRL_UNIPOLAR_BIT, cfg.bipolar ? 0 : 1); + ret = regmap_update_bits(st->regmap, MAX11410_REG_CTRL, + MAX11410_CTRL_REFSEL_MASK | + MAX11410_CTRL_VREFP_BUF_BIT | + MAX11410_CTRL_VREFN_BUF_BIT | + MAX11410_CTRL_UNIPOLAR_BIT, regval); + if (ret) + return ret; + + regval = FIELD_PREP(MAX11410_PGA_SIG_PATH_MASK, cfg.sig_path) | + FIELD_PREP(MAX11410_PGA_GAIN_MASK, cfg.gain); + ret = regmap_write(st->regmap, MAX11410_REG_PGA, regval); + if (ret) + return ret; + + if (cfg.settling_time_us) + fsleep(cfg.settling_time_us); + + return 0; +} + +static int max11410_sample(struct max11410_state *st, int *sample_raw, + struct iio_chan_spec const *chan) +{ + int val, ret; + + ret = max11410_configure_channel(st, chan); + if (ret) + return ret; + + if (st->irq > 0) + reinit_completion(&st->completion); + + /* Start Conversion */ + ret = max11410_write_reg(st, MAX11410_REG_CONV_START, + MAX11410_CONV_TYPE_SINGLE); + if (ret) + return ret; + + if (st->irq > 0) { + /* Wait for an interrupt. */ + ret = wait_for_completion_timeout(&st->completion, + msecs_to_jiffies(MAX11410_CONVERSION_TIMEOUT_MS)); + if (!ret) + return -ETIMEDOUT; + } else { + /* Wait for status register Conversion Ready flag */ + ret = read_poll_timeout(max11410_read_reg, ret, + ret || (val & MAX11410_STATUS_CONV_READY_BIT), + 5000, MAX11410_CONVERSION_TIMEOUT_MS * 1000, + true, st, MAX11410_REG_STATUS, &val); + if (ret) + return ret; + } + + /* Read ADC Data */ + return max11410_read_reg(st, MAX11410_REG_DATA0, sample_raw); +} + +static int max11410_get_scale(struct max11410_state *state, + struct max11410_channel_config cfg) +{ + struct regulator *vrefp, *vrefn; + int scale; + + vrefp = max11410_get_vrefp(state, cfg.refsel); + + scale = regulator_get_voltage(vrefp) / 1000; + vrefn = max11410_get_vrefn(state, cfg.refsel); + if (vrefn) + scale -= regulator_get_voltage(vrefn) / 1000; + + if (cfg.bipolar) + scale *= 2; + + return scale >> cfg.gain; +} + +static int max11410_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long info) +{ + struct max11410_state *state = iio_priv(indio_dev); + struct max11410_channel_config cfg = state->channels[chan->address]; + int ret, reg_val, filter, rate; + + switch (info) { + case IIO_CHAN_INFO_SCALE: + *val = max11410_get_scale(state, cfg); + *val2 = chan->scan_type.realbits; + return IIO_VAL_FRACTIONAL_LOG2; + case IIO_CHAN_INFO_OFFSET: + if (cfg.bipolar) + *val = -BIT(chan->scan_type.realbits - 1); + else + *val = 0; + + return IIO_VAL_INT; + case IIO_CHAN_INFO_RAW: + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) + return ret; + + mutex_lock(&state->lock); + + ret = max11410_sample(state, ®_val, chan); + + mutex_unlock(&state->lock); + + iio_device_release_direct_mode(indio_dev); + + if (ret) + return ret; + + *val = reg_val; + + return IIO_VAL_INT; + case IIO_CHAN_INFO_SAMP_FREQ: + ret = regmap_read(state->regmap, MAX11410_REG_FILTER, ®_val); + if (ret) + return ret; + + filter = FIELD_GET(MAX11410_FILTER_LINEF_MASK, reg_val); + rate = reg_val & MAX11410_FILTER_RATE_MASK; + if (rate >= max11410_sampling_len[filter]) + rate = max11410_sampling_len[filter] - 1; + + *val = max11410_sampling_rates[filter][rate][0]; + *val2 = max11410_sampling_rates[filter][rate][1]; + + return IIO_VAL_INT_PLUS_MICRO; + } + return -EINVAL; +} + +static int max11410_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct max11410_state *st = iio_priv(indio_dev); + int i, ret, reg_val, filter, gain; + u32 *scale_avail; + + switch (mask) { + case IIO_CHAN_INFO_SCALE: + scale_avail = st->channels[chan->address].scale_avail; + if (!scale_avail) + return -EOPNOTSUPP; + + /* Accept values in range 0.000001 <= scale < 1.000000 */ + if (val != 0 || val2 == 0) + return -EINVAL; + + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) + return ret; + + /* Convert from INT_PLUS_MICRO to FRACTIONAL_LOG2 */ + val2 = val2 * DIV_ROUND_CLOSEST(BIT(24), 1000000); + val2 = DIV_ROUND_CLOSEST(scale_avail[0], val2); + gain = order_base_2(val2); + + st->channels[chan->address].gain = clamp_val(gain, 0, 7); + + iio_device_release_direct_mode(indio_dev); + + return 0; + case IIO_CHAN_INFO_SAMP_FREQ: + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) + return ret; + + mutex_lock(&st->lock); + + ret = regmap_read(st->regmap, MAX11410_REG_FILTER, ®_val); + if (ret) + goto out; + + filter = FIELD_GET(MAX11410_FILTER_LINEF_MASK, reg_val); + + for (i = 0; i < max11410_sampling_len[filter]; ++i) { + if (val == max11410_sampling_rates[filter][i][0] && + val2 == max11410_sampling_rates[filter][i][1]) + break; + } + if (i == max11410_sampling_len[filter]) { + ret = -EINVAL; + goto out; + } + + ret = regmap_write_bits(st->regmap, MAX11410_REG_FILTER, + MAX11410_FILTER_RATE_MASK, i); + +out: + mutex_unlock(&st->lock); + iio_device_release_direct_mode(indio_dev); + + return ret; + default: + return -EINVAL; + } +} + +static int max11410_read_avail(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int **vals, int *type, int *length, + long info) +{ + struct max11410_state *st = iio_priv(indio_dev); + struct max11410_channel_config cfg; + int ret, reg_val, filter; + + switch (info) { + case IIO_CHAN_INFO_SAMP_FREQ: + ret = regmap_read(st->regmap, MAX11410_REG_FILTER, ®_val); + if (ret) + return ret; + + filter = FIELD_GET(MAX11410_FILTER_LINEF_MASK, reg_val); + + *vals = (const int *)max11410_sampling_rates[filter]; + *length = max11410_sampling_len[filter] * 2; + *type = IIO_VAL_INT_PLUS_MICRO; + + return IIO_AVAIL_LIST; + case IIO_CHAN_INFO_SCALE: + cfg = st->channels[chan->address]; + + if (!cfg.scale_avail) + return -EINVAL; + + *vals = cfg.scale_avail; + *length = MAX11410_SCALE_AVAIL_SIZE * 2; + *type = IIO_VAL_FRACTIONAL_LOG2; + + return IIO_AVAIL_LIST; + } + return -EINVAL; +} + +static const struct iio_info max11410_info = { + .read_raw = max11410_read_raw, + .write_raw = max11410_write_raw, + .read_avail = max11410_read_avail, + .attrs = &max11410_attribute_group, +}; + +static irqreturn_t max11410_trigger_handler(int irq, void *p) +{ + struct iio_poll_func *pf = p; + struct iio_dev *indio_dev = pf->indio_dev; + struct max11410_state *st = iio_priv(indio_dev); + int ret; + + ret = max11410_read_reg(st, MAX11410_REG_DATA0, &st->scan.data); + if (ret) { + dev_err(&indio_dev->dev, "cannot read data\n"); + goto out; + } + + iio_push_to_buffers_with_timestamp(indio_dev, &st->scan, + iio_get_time_ns(indio_dev)); + +out: + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + +static int max11410_buffer_postenable(struct iio_dev *indio_dev) +{ + struct max11410_state *st = iio_priv(indio_dev); + int scan_ch, ret; + + scan_ch = ffs(*indio_dev->active_scan_mask) - 1; + + ret = max11410_configure_channel(st, &indio_dev->channels[scan_ch]); + if (ret) + return ret; + + /* Start continuous conversion. */ + return max11410_write_reg(st, MAX11410_REG_CONV_START, + MAX11410_CONV_TYPE_CONTINUOUS); +} + +static int max11410_buffer_predisable(struct iio_dev *indio_dev) +{ + struct max11410_state *st = iio_priv(indio_dev); + + /* Stop continuous conversion. */ + return max11410_write_reg(st, MAX11410_REG_CONV_START, + MAX11410_CONV_TYPE_SINGLE); +} + +static const struct iio_buffer_setup_ops max11410_buffer_ops = { + .postenable = &max11410_buffer_postenable, + .predisable = &max11410_buffer_predisable, + .validate_scan_mask = &iio_validate_scan_mask_onehot, +}; + +static const struct iio_trigger_ops max11410_trigger_ops = { + .validate_device = iio_trigger_validate_own_device, +}; + +static irqreturn_t max11410_interrupt(int irq, void *dev_id) +{ + struct iio_dev *indio_dev = dev_id; + struct max11410_state *st = iio_priv(indio_dev); + + if (iio_buffer_enabled(indio_dev)) + iio_trigger_poll_chained(st->trig); + else + complete(&st->completion); + + return IRQ_HANDLED; +}; + +static int max11410_parse_channels(struct max11410_state *st, + struct iio_dev *indio_dev) +{ + struct iio_chan_spec chanspec = chanspec_template; + struct device *dev = &st->spi_dev->dev; + struct max11410_channel_config *cfg; + struct iio_chan_spec *channels; + struct fwnode_handle *child; + u32 reference, sig_path; + const char *node_name; + u32 inputs[2], scale; + unsigned int num_ch; + int chan_idx = 0; + int ret, i; + + num_ch = device_get_child_node_count(dev); + if (num_ch == 0) + return dev_err_probe(&indio_dev->dev, -ENODEV, + "FW has no channels defined\n"); + + /* Reserve space for soft timestamp channel */ + num_ch++; + channels = devm_kcalloc(dev, num_ch, sizeof(*channels), GFP_KERNEL); + if (!channels) + return -ENOMEM; + + st->channels = devm_kcalloc(dev, num_ch, sizeof(*st->channels), + GFP_KERNEL); + if (!st->channels) + return -ENOMEM; + + device_for_each_child_node(dev, child) { + node_name = fwnode_get_name(child); + if (fwnode_property_present(child, "diff-channels")) { + ret = fwnode_property_read_u32_array(child, + "diff-channels", + inputs, + ARRAY_SIZE(inputs)); + + chanspec.differential = 1; + } else { + ret = fwnode_property_read_u32(child, "reg", &inputs[0]); + + inputs[1] = 0; + chanspec.differential = 0; + } + if (ret) { + fwnode_handle_put(child); + return ret; + } + + if (inputs[0] > MAX11410_CHANNEL_INDEX_MAX || + inputs[1] > MAX11410_CHANNEL_INDEX_MAX) { + fwnode_handle_put(child); + return dev_err_probe(&indio_dev->dev, -EINVAL, + "Invalid channel index for %s, should be less than %d\n", + node_name, + MAX11410_CHANNEL_INDEX_MAX + 1); + } + + cfg = &st->channels[chan_idx]; + + reference = MAX11410_REFSEL_AVDD_AGND; + fwnode_property_read_u32(child, "adi,reference", &reference); + if (reference > MAX11410_REFSEL_MAX) { + fwnode_handle_put(child); + return dev_err_probe(&indio_dev->dev, -EINVAL, + "Invalid adi,reference value for %s, should be less than %d.\n", + node_name, MAX11410_REFSEL_MAX + 1); + } + + if (!max11410_get_vrefp(st, reference) || + (!max11410_get_vrefn(st, reference) && reference <= 2)) { + fwnode_handle_put(child); + return dev_err_probe(&indio_dev->dev, -EINVAL, + "Invalid VREF configuration for %s, either specify corresponding VREF regulators or change adi,reference property.\n", + node_name); + } + + sig_path = MAX11410_PGA_SIG_PATH_BUFFERED; + fwnode_property_read_u32(child, "adi,input-mode", &sig_path); + if (sig_path > MAX11410_SIG_PATH_MAX) { + fwnode_handle_put(child); + return dev_err_probe(&indio_dev->dev, -EINVAL, + "Invalid adi,input-mode value for %s, should be less than %d.\n", + node_name, MAX11410_SIG_PATH_MAX + 1); + } + + fwnode_property_read_u32(child, "settling-time-us", + &cfg->settling_time_us); + cfg->bipolar = fwnode_property_read_bool(child, "bipolar"); + cfg->buffered_vrefp = fwnode_property_read_bool(child, "adi,buffered-vrefp"); + cfg->buffered_vrefn = fwnode_property_read_bool(child, "adi,buffered-vrefn"); + cfg->refsel = reference; + cfg->sig_path = sig_path; + cfg->gain = 0; + + /* Enable scale_available property if input mode is PGA */ + if (sig_path == MAX11410_PGA_SIG_PATH_PGA) { + __set_bit(IIO_CHAN_INFO_SCALE, + &chanspec.info_mask_separate_available); + cfg->scale_avail = devm_kcalloc(dev, MAX11410_SCALE_AVAIL_SIZE * 2, + sizeof(*cfg->scale_avail), + GFP_KERNEL); + if (!cfg->scale_avail) { + fwnode_handle_put(child); + return -ENOMEM; + } + + scale = max11410_get_scale(st, *cfg); + for (i = 0; i < MAX11410_SCALE_AVAIL_SIZE; i++) { + cfg->scale_avail[2 * i] = scale >> i; + cfg->scale_avail[2 * i + 1] = chanspec.scan_type.realbits; + } + } else { + __clear_bit(IIO_CHAN_INFO_SCALE, + &chanspec.info_mask_separate_available); + } + + chanspec.address = chan_idx; + chanspec.scan_index = chan_idx; + chanspec.channel = inputs[0]; + chanspec.channel2 = inputs[1]; + + channels[chan_idx] = chanspec; + chan_idx++; + } + + channels[chan_idx] = (struct iio_chan_spec)IIO_CHAN_SOFT_TIMESTAMP(chan_idx); + + indio_dev->num_channels = chan_idx + 1; + indio_dev->channels = channels; + + return 0; +} + +static void max11410_disable_reg(void *reg) +{ + regulator_disable(reg); +} + +static int max11410_init_vref(struct device *dev, + struct regulator **vref, + const char *id) +{ + struct regulator *reg; + int ret; + + reg = devm_regulator_get_optional(dev, id); + if (PTR_ERR(reg) == -ENODEV) { + *vref = NULL; + return 0; + } else if (IS_ERR(reg)) { + return PTR_ERR(reg); + } + ret = regulator_enable(reg); + if (ret) + return dev_err_probe(dev, ret, + "Failed to enable regulator %s\n", id); + + *vref = reg; + return devm_add_action_or_reset(dev, max11410_disable_reg, reg); +} + +static int max11410_calibrate(struct max11410_state *st, u32 cal_type) +{ + int ret, val; + + ret = max11410_write_reg(st, MAX11410_REG_CAL_START, cal_type); + if (ret) + return ret; + + /* Wait for status register Calibration Ready flag */ + return read_poll_timeout(max11410_read_reg, ret, + ret || (val & MAX11410_STATUS_CAL_READY_BIT), + 50000, MAX11410_CALIB_TIMEOUT_MS * 1000, true, + st, MAX11410_REG_STATUS, &val); +} + +static int max11410_self_calibrate(struct max11410_state *st) +{ + int ret, i; + + ret = regmap_write_bits(st->regmap, MAX11410_REG_FILTER, + MAX11410_FILTER_RATE_MASK, + FIELD_PREP(MAX11410_FILTER_RATE_MASK, + MAX11410_FILTER_RATE_MAX)); + if (ret) + return ret; + + ret = max11410_calibrate(st, MAX11410_CAL_START_SELF); + if (ret) + return ret; + + ret = regmap_write_bits(st->regmap, MAX11410_REG_PGA, + MAX11410_PGA_SIG_PATH_MASK, + FIELD_PREP(MAX11410_PGA_SIG_PATH_MASK, + MAX11410_PGA_SIG_PATH_PGA)); + if (ret) + return ret; + + /* PGA calibrations */ + for (i = 1; i < 8; ++i) { + ret = regmap_write_bits(st->regmap, MAX11410_REG_PGA, + MAX11410_PGA_GAIN_MASK, i); + if (ret) + return ret; + + ret = max11410_calibrate(st, MAX11410_CAL_START_PGA); + if (ret) + return ret; + } + + /* Cleanup */ + ret = regmap_write_bits(st->regmap, MAX11410_REG_PGA, + MAX11410_PGA_GAIN_MASK, 0); + if (ret) + return ret; + + ret = regmap_write_bits(st->regmap, MAX11410_REG_FILTER, + MAX11410_FILTER_RATE_MASK, 0); + if (ret) + return ret; + + return regmap_write_bits(st->regmap, MAX11410_REG_PGA, + MAX11410_PGA_SIG_PATH_MASK, + FIELD_PREP(MAX11410_PGA_SIG_PATH_MASK, + MAX11410_PGA_SIG_PATH_BUFFERED)); +} + +static int max11410_probe(struct spi_device *spi) +{ + const char *vrefp_regs[] = { "vref0p", "vref1p", "vref2p" }; + const char *vrefn_regs[] = { "vref0n", "vref1n", "vref2n" }; + struct device *dev = &spi->dev; + struct max11410_state *st; + struct iio_dev *indio_dev; + int ret, irqs[2]; + int i; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + st->spi_dev = spi; + init_completion(&st->completion); + mutex_init(&st->lock); + + indio_dev->name = "max11410"; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->info = &max11410_info; + + st->regmap = devm_regmap_init_spi(spi, ®map_config); + if (IS_ERR(st->regmap)) + return dev_err_probe(dev, PTR_ERR(st->regmap), + "regmap initialization failed\n"); + + ret = max11410_init_vref(dev, &st->avdd, "avdd"); + if (ret) + return ret; + + for (i = 0; i < ARRAY_SIZE(vrefp_regs); i++) { + ret = max11410_init_vref(dev, &st->vrefp[i], vrefp_regs[i]); + if (ret) + return ret; + + ret = max11410_init_vref(dev, &st->vrefn[i], vrefn_regs[i]); + if (ret) + return ret; + } + + /* + * Regulators must be configured before parsing channels for + * validating "adi,reference" property of each channel. + */ + ret = max11410_parse_channels(st, indio_dev); + if (ret) + return ret; + + irqs[0] = fwnode_irq_get_byname(dev_fwnode(dev), "gpio0"); + irqs[1] = fwnode_irq_get_byname(dev_fwnode(dev), "gpio1"); + + if (irqs[0] > 0) { + st->irq = irqs[0]; + ret = regmap_write(st->regmap, MAX11410_REG_GPIO_CTRL(0), + MAX11410_GPIO_INTRB); + } else if (irqs[1] > 0) { + st->irq = irqs[1]; + ret = regmap_write(st->regmap, MAX11410_REG_GPIO_CTRL(1), + MAX11410_GPIO_INTRB); + } else if (spi->irq > 0) { + return dev_err_probe(dev, -ENODEV, + "no interrupt name specified"); + } + + if (ret) + return ret; + + ret = regmap_set_bits(st->regmap, MAX11410_REG_CTRL, + MAX11410_CTRL_FORMAT_BIT); + if (ret) + return ret; + + ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, + &max11410_trigger_handler, + &max11410_buffer_ops); + if (ret) + return ret; + + if (st->irq > 0) { + st->trig = devm_iio_trigger_alloc(dev, "%s-dev%d", + indio_dev->name, + iio_device_id(indio_dev)); + if (!st->trig) + return -ENOMEM; + + st->trig->ops = &max11410_trigger_ops; + ret = devm_iio_trigger_register(dev, st->trig); + if (ret) + return ret; + + ret = devm_request_threaded_irq(dev, st->irq, NULL, + &max11410_interrupt, + IRQF_ONESHOT, "max11410", + indio_dev); + if (ret) + return ret; + } + + ret = max11410_self_calibrate(st); + if (ret) + return dev_err_probe(dev, ret, + "cannot perform device self calibration\n"); + + return devm_iio_device_register(dev, indio_dev); +} + +static const struct of_device_id max11410_spi_of_id[] = { + { .compatible = "adi,max11410" }, + { } +}; +MODULE_DEVICE_TABLE(of, max11410_spi_of_id); + +static const struct spi_device_id max11410_id[] = { + { "max11410" }, + { } +}; +MODULE_DEVICE_TABLE(spi, max11410_id); + +static struct spi_driver max11410_driver = { + .driver = { + .name = "max11410", + .of_match_table = max11410_spi_of_id, + }, + .probe = max11410_probe, + .id_table = max11410_id, +}; +module_spi_driver(max11410_driver); + +MODULE_AUTHOR("David Jung <David.Jung@analog.com>"); +MODULE_AUTHOR("Ibrahim Tilki <Ibrahim.Tilki@analog.com>"); +MODULE_DESCRIPTION("Analog Devices MAX11410 ADC"); +MODULE_LICENSE("GPL"); |