Add a driver for the AD762x and AD796x family of ADCs. These are pin-compatible devices using an LVDS interface for data transfer, capable of sampling at rates of 6 (AD7625), 10 (AD7626), and 5 (AD7960/AD7961) MSPS, respectively. They also feature multiple voltage reference options based on the configuration of the EN1/EN0 pins, which can be set in the devicetree. Signed-off-by: Trevor Gamblin <tgamblin@xxxxxxxxxxxx> --- MAINTAINERS | 1 + drivers/iio/adc/Kconfig | 16 ++ drivers/iio/adc/Makefile | 1 + drivers/iio/adc/ad7625.c | 684 +++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 702 insertions(+) diff --git a/MAINTAINERS b/MAINTAINERS index 77557e85220e..7f77a1c1110b 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1279,6 +1279,7 @@ S: Supported W: https://ez.analog.com/linux-software-drivers W: http://analogdevicesinc.github.io/hdl/projects/pulsar_lvds/index.html F: Documentation/devicetree/bindings/iio/adc/adi,ad7625.yaml +F: drivers/iio/adc/ad7625.c ANALOG DEVICES INC AD7768-1 DRIVER M: Michael Hennerich <Michael.Hennerich@xxxxxxxxxx> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index f60fe85a30d5..2e743c95e900 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -219,6 +219,22 @@ config AD7606_IFACE_SPI To compile this driver as a module, choose M here: the module will be called ad7606_spi. +config AD7625 + tristate "Analog Devices AD7625/AD7626 High Speed ADC driver" + depends on PWM + select IIO_BACKEND + help + Say yes here to build support for Analog Devices: + * AD7625 16-Bit, 6 MSPS PulSAR Analog-to-Digital Converter + * AD7626 16-Bit, 10 MSPS PulSAR Analog-to-Digital Converter + * AD7960 18-Bit, 5 MSPS PulSAR Analog-to-Digital Converter + * AD7961 16-Bit, 5 MSPS PulSAR Analog-to-Digital Converter + + The driver requires the assistance of the AXI ADC IP core to operate. + + To compile this driver as a module, choose M here: the module will be + called ad7625. + config AD7766 tristate "Analog Devices AD7766/AD7767 ADC driver" depends on SPI_MASTER diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile index d370e066544e..6bf429ca24ea 100644 --- a/drivers/iio/adc/Makefile +++ b/drivers/iio/adc/Makefile @@ -23,6 +23,7 @@ obj-$(CONFIG_AD7476) += ad7476.o obj-$(CONFIG_AD7606_IFACE_PARALLEL) += ad7606_par.o obj-$(CONFIG_AD7606_IFACE_SPI) += ad7606_spi.o obj-$(CONFIG_AD7606) += ad7606.o +obj-$(CONFIG_AD7625) += ad7625.o obj-$(CONFIG_AD7766) += ad7766.o obj-$(CONFIG_AD7768_1) += ad7768-1.o obj-$(CONFIG_AD7780) += ad7780.o diff --git a/drivers/iio/adc/ad7625.c b/drivers/iio/adc/ad7625.c new file mode 100644 index 000000000000..5faada8d510f --- /dev/null +++ b/drivers/iio/adc/ad7625.c @@ -0,0 +1,684 @@ +// SPDX-License-Identifier: (GPL-2.0-only OR BSD-3-Clause) +/* + * Analog Devices Inc. AD7625 ADC driver + * + * Copyright 2024 Analog Devices Inc. + * Copyright 2024 BayLibre, SAS + * + * Note that this driver requires the AXI ADC IP block configured for + * LVDS to function. See Documentation/iio/ad7625.rst for more + * information. + */ + +#include <linux/clk.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/gpio/consumer.h> +#include <linux/iio/backend.h> +#include <linux/iio/iio.h> +#include <linux/kernel.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/pwm.h> +#include <linux/regulator/consumer.h> +#include <linux/units.h> + +#define AD7625_INTERNAL_REF_MV 4096 +#define AD7960_MAX_NBW_FREQ (2 * MEGA) + +struct ad7625_timing_spec { + /* Max conversion high time (t_{CNVH}). */ + unsigned int conv_high_ns; + /* Max conversion to MSB delay (t_{MSB}). */ + unsigned int conv_msb_ns; +}; + +struct ad7625_chip_info { + const char *name; + const unsigned int max_sample_rate_hz; + const struct ad7625_timing_spec *timing_spec; + const struct iio_chan_spec chan_spec; + const bool has_power_down_state; + const bool has_bandwidth_control; + const bool has_internal_vref; +}; + +/* AD7625_CHAN_SPEC - Define a chan spec structure for a specific chip */ +#define AD7625_CHAN_SPEC(_bits) { \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .differential = 1, \ + .channel = 0, \ + .channel2 = 1, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_SCALE), \ + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \ + .scan_index = 0, \ + .scan_type.sign = 's', \ + .scan_type.storagebits = (_bits) > 16 ? 32 : 16, \ + .scan_type.realbits = (_bits), \ +} + +struct ad7625_state { + const struct ad7625_chip_info *info; + struct iio_backend *back; + /* rate of the clock gated by the "clk_gate" PWM */ + unsigned long ref_clk_rate_hz; + /* PWM burst signal for transferring acquired data to the host */ + struct pwm_device *clk_gate_pwm; + /* + * PWM control signal for initiating data conversion. Analog + * inputs are sampled beginning on this signal's rising edge. + */ + struct pwm_device *cnv_pwm; + /* + * Waveforms containing the last-requested and rounded + * properties for the clk_gate and cnv PWMs + */ + struct pwm_waveform clk_gate_wf; + struct pwm_waveform cnv_wf; + unsigned int vref_mv; + int sampling_freq_hz; + /* + * Optional GPIOs for controlling device state. EN0 and EN1 + * determine voltage reference configuration and on/off state. + * EN2 controls the device -3dB bandwidth (and by extension, max + * sample rate). EN3 controls the VCM reference output. EN2 and + * EN3 are only present for the AD796x devices. + */ + struct gpio_desc *en_gpios[4]; + bool can_power_down; + bool can_refin; + bool can_ref_4v096; + /* + * Indicate whether the bandwidth can be narrow (9MHz). + * When true, device sample rate must also be < 2MSPS. + */ + bool can_narrow_bandwidth; + /* Indicate whether the bandwidth can be wide (28MHz). */ + bool can_wide_bandwidth; + bool can_ref_5v; + bool can_snooze; + bool can_test_pattern; + /* Indicate whether there is a REFIN supply connected */ + bool have_refin; +}; + +static const struct ad7625_timing_spec ad7625_timing_spec = { + .conv_high_ns = 40, + .conv_msb_ns = 145, +}; + +static const struct ad7625_timing_spec ad7626_timing_spec = { + .conv_high_ns = 40, + .conv_msb_ns = 80, +}; + +/* + * conv_msb_ns is set to 0 instead of the datasheet maximum of 200ns to + * avoid exceeding the minimum conversion time, i.e. it is effectively + * modulo 200 and offset by a full period. Values greater than or equal + * to the period would be rejected by the PWM API. + */ +static const struct ad7625_timing_spec ad7960_timing_spec = { + .conv_high_ns = 80, + .conv_msb_ns = 0, +}; + +static const struct ad7625_chip_info ad7625_chip_info = { + .name = "ad7625", + .max_sample_rate_hz = 6 * MEGA, + .timing_spec = &ad7625_timing_spec, + .chan_spec = AD7625_CHAN_SPEC(16), + .has_power_down_state = false, + .has_bandwidth_control = false, + .has_internal_vref = true, +}; + +static const struct ad7625_chip_info ad7626_chip_info = { + .name = "ad7626", + .max_sample_rate_hz = 10 * MEGA, + .timing_spec = &ad7626_timing_spec, + .chan_spec = AD7625_CHAN_SPEC(16), + .has_power_down_state = true, + .has_bandwidth_control = false, + .has_internal_vref = true, +}; + +static const struct ad7625_chip_info ad7960_chip_info = { + .name = "ad7960", + .max_sample_rate_hz = 5 * MEGA, + .timing_spec = &ad7960_timing_spec, + .chan_spec = AD7625_CHAN_SPEC(18), + .has_power_down_state = true, + .has_bandwidth_control = true, + .has_internal_vref = false, +}; + +static const struct ad7625_chip_info ad7961_chip_info = { + .name = "ad7961", + .max_sample_rate_hz = 5 * MEGA, + .timing_spec = &ad7960_timing_spec, + .chan_spec = AD7625_CHAN_SPEC(16), + .has_power_down_state = true, + .has_bandwidth_control = true, + .has_internal_vref = false, +}; + +enum ad7960_mode { + AD7960_MODE_POWER_DOWN, + AD7960_MODE_SNOOZE, + AD7960_MODE_NARROW_BANDWIDTH, + AD7960_MODE_WIDE_BANDWIDTH, + AD7960_MODE_TEST_PATTERN, +}; + +static int ad7625_set_sampling_freq(struct ad7625_state *st, int freq) +{ + u64 target; + struct pwm_waveform clk_gate_wf = { }, cnv_wf = { }; + int ret; + + target = DIV_ROUND_UP_ULL(NSEC_PER_SEC, freq); + cnv_wf.period_length_ns = clamp(target, 100, 10 * KILO); + + /* + * Use the maximum conversion time t_CNVH from the datasheet as + * the duty_cycle for ref_clk, cnv, and clk_gate + */ + cnv_wf.duty_length_ns = st->info->timing_spec->conv_high_ns; + + ret = pwm_round_waveform_might_sleep(st->cnv_pwm, &cnv_wf); + if (ret) + return ret; + + /* + * Set up the burst signal for transferring data. period and + * offset should mirror the CNV signal + */ + clk_gate_wf.period_length_ns = cnv_wf.period_length_ns; + + clk_gate_wf.duty_length_ns = DIV_ROUND_UP_ULL((u64)NSEC_PER_SEC * + st->info->chan_spec.scan_type.realbits, + st->ref_clk_rate_hz); + + /* max t_MSB from datasheet */ + clk_gate_wf.duty_offset_ns = st->info->timing_spec->conv_msb_ns; + + ret = pwm_round_waveform_might_sleep(st->clk_gate_pwm, &clk_gate_wf); + if (ret) + return ret; + + st->cnv_wf = cnv_wf; + st->clk_gate_wf = clk_gate_wf; + + /* TODO: Add a rounding API for PWMs that can simplify this */ + target = DIV_ROUND_CLOSEST_ULL(st->ref_clk_rate_hz, freq); + st->sampling_freq_hz = DIV_ROUND_CLOSEST_ULL(st->ref_clk_rate_hz, + target); + + return 0; +} + +static int ad7625_read_raw(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + int *val, int *val2, long info) +{ + struct ad7625_state *st = iio_priv(indio_dev); + + switch (info) { + case IIO_CHAN_INFO_SAMP_FREQ: + *val = st->sampling_freq_hz; + + return IIO_VAL_INT; + + case IIO_CHAN_INFO_SCALE: + *val = st->vref_mv; + *val2 = chan->scan_type.realbits - 1; + + return IIO_VAL_FRACTIONAL_LOG2; + + default: + return -EINVAL; + } +} + +static int ad7625_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long info) +{ + struct ad7625_state *st = iio_priv(indio_dev); + + switch (info) { + case IIO_CHAN_INFO_SAMP_FREQ: + iio_device_claim_direct_scoped(return -EBUSY, indio_dev) + return ad7625_set_sampling_freq(st, val); + unreachable(); + default: + return -EINVAL; + } +} + +static int ad7625_parse_mode(struct device *dev, struct ad7625_state *st, + int num_gpios) +{ + bool en_always_on[4], en_always_off[4]; + bool en_may_be_on[4], en_may_be_off[4]; + char en_gpio_buf[4]; + char always_on_buf[18]; + int i; + + for (i = 0; i < num_gpios; i++) { + snprintf(en_gpio_buf, sizeof(en_gpio_buf), "en%d", i); + snprintf(always_on_buf, sizeof(always_on_buf), + "adi,en%d-always-on", i); + /* Set the device to 0b0000 (power-down mode) by default */ + st->en_gpios[i] = devm_gpiod_get_optional(dev, en_gpio_buf, + GPIOD_OUT_LOW); + if (IS_ERR(st->en_gpios[i])) + return dev_err_probe(dev, PTR_ERR(st->en_gpios[i]), + "failed to get EN%d GPIO\n", i); + + en_always_on[i] = device_property_read_bool(dev, always_on_buf); + if (st->en_gpios[i] && en_always_on[i]) + return dev_err_probe(dev, -EINVAL, + "cannot have adi,en%d-always-on and en%d-gpios\n", i, i); + + en_may_be_off[i] = !en_always_on[i]; + en_may_be_on[i] = en_always_on[i] || st->en_gpios[i]; + en_always_off[i] = !en_always_on[i] && !st->en_gpios[i]; + } + + /* + * Power down is mode 0bXX00, but not all devices have a valid + * power down state. + */ + st->can_power_down = en_may_be_off[1] && en_may_be_off[0] && + st->info->has_power_down_state; + /* + * The REFIN pin can take a 1.2V (AD762x) or 2.048V (AD796x) + * external reference when the mode is 0bXX01. + */ + st->can_refin = en_may_be_off[1] && en_may_be_on[0]; + /* 4.096V can be applied to REF when the EN mode is 0bXX10. */ + st->can_ref_4v096 = en_may_be_on[1] && en_may_be_off[0]; + + /* Avoid AD796x-specific setup if the part is an AD762x */ + if (num_gpios == 2) + return 0; + + /* mode 0b1100 (AD796x) is invalid */ + if (en_always_on[3] && en_always_on[2] && + en_always_off[1] && en_always_off[0]) + return dev_err_probe(dev, -EINVAL, + "EN GPIOs set to invalid mode 0b1100\n"); + /* + * 5V can be applied to the AD796x REF pin when the EN mode is + * the same (0bX001 or 0bX101) as for can_refin, and REFIN is + * 0V. + */ + st->can_ref_5v = st->can_refin; + /* + * Bandwidth (AD796x) is controlled solely by EN2. If it's + * specified and not hard-wired, then we can configure it to + * change the bandwidth between 28MHz and 9MHz. + */ + st->can_narrow_bandwidth = en_may_be_on[2]; + /* Wide bandwidth mode is possible if EN2 can be 0. */ + st->can_wide_bandwidth = en_may_be_off[2]; + /* Snooze mode (AD796x) is 0bXX11 when REFIN = 0V. */ + st->can_snooze = en_may_be_on[1] && en_may_be_on[0]; + /* Test pattern mode (AD796x) is 0b0100. */ + st->can_test_pattern = en_may_be_off[3] && en_may_be_on[2] && + en_may_be_off[1] && en_may_be_off[0]; + + return 0; +} + +/* Set EN1 and EN0 based on reference voltage source */ +static void ad7625_set_en_gpios_for_vref(struct ad7625_state *st, + bool have_refin, int ref_mv) +{ + if (have_refin || ref_mv == 5000) { + gpiod_set_value_cansleep(st->en_gpios[1], 0); + gpiod_set_value_cansleep(st->en_gpios[0], 1); + } else if (ref_mv == 4096) { + gpiod_set_value_cansleep(st->en_gpios[1], 1); + gpiod_set_value_cansleep(st->en_gpios[0], 0); + } else { + /* + * Unreachable by AD796x, since the driver will error if + * neither REF nor REFIN is provided + */ + gpiod_set_value_cansleep(st->en_gpios[1], 1); + gpiod_set_value_cansleep(st->en_gpios[0], 1); + } +} + +static int ad7960_set_mode(struct ad7625_state *st, enum ad7960_mode mode, + bool have_refin, int ref_mv) +{ + switch (mode) { + case AD7960_MODE_POWER_DOWN: + if (!st->can_power_down) + return -EINVAL; + + gpiod_set_value_cansleep(st->en_gpios[2], 0); + gpiod_set_value_cansleep(st->en_gpios[1], 0); + gpiod_set_value_cansleep(st->en_gpios[0], 0); + + return 0; + + case AD7960_MODE_SNOOZE: + if (!st->can_snooze) + return -EINVAL; + + gpiod_set_value_cansleep(st->en_gpios[1], 1); + gpiod_set_value_cansleep(st->en_gpios[0], 1); + + return 0; + + case AD7960_MODE_NARROW_BANDWIDTH: + if (!st->can_narrow_bandwidth) + return -EINVAL; + + gpiod_set_value_cansleep(st->en_gpios[2], 1); + ad7625_set_en_gpios_for_vref(st, have_refin, ref_mv); + + return 0; + + case AD7960_MODE_WIDE_BANDWIDTH: + if (!st->can_wide_bandwidth) + return -EINVAL; + + gpiod_set_value_cansleep(st->en_gpios[2], 0); + ad7625_set_en_gpios_for_vref(st, have_refin, ref_mv); + + return 0; + + case AD7960_MODE_TEST_PATTERN: + if (!st->can_test_pattern) + return -EINVAL; + + gpiod_set_value_cansleep(st->en_gpios[3], 0); + gpiod_set_value_cansleep(st->en_gpios[2], 1); + gpiod_set_value_cansleep(st->en_gpios[1], 0); + gpiod_set_value_cansleep(st->en_gpios[0], 0); + + return 0; + + default: + return -EINVAL; + } +} + +static int ad7625_buffer_preenable(struct iio_dev *indio_dev) +{ + struct ad7625_state *st = iio_priv(indio_dev); + int ret; + + ret = pwm_set_waveform_might_sleep(st->cnv_pwm, &st->cnv_wf, false); + if (ret) + return ret; + + ret = pwm_set_waveform_might_sleep(st->clk_gate_pwm, + &st->clk_gate_wf, false); + if (ret) { + /* Disable cnv PWM if clk_gate setup failed */ + pwm_disable(st->cnv_pwm); + return ret; + } + + return 0; +} + +static int ad7625_buffer_postdisable(struct iio_dev *indio_dev) +{ + struct ad7625_state *st = iio_priv(indio_dev); + + pwm_disable(st->cnv_pwm); + pwm_disable(st->clk_gate_pwm); + + return 0; +} + +static const struct iio_info ad7625_info = { + .read_raw = ad7625_read_raw, + .write_raw = ad7625_write_raw, +}; + +static const struct iio_buffer_setup_ops ad7625_buffer_setup_ops = { + .preenable = &ad7625_buffer_preenable, + .postdisable = &ad7625_buffer_postdisable, +}; + +static int devm_ad7625_pwm_get(struct device *dev, struct clk *ref_clk, + struct ad7625_state *st) +{ + unsigned long ref_clk_rate_hz; + + st->cnv_pwm = devm_pwm_get(dev, "cnv"); + if (IS_ERR(st->cnv_pwm)) + return dev_err_probe(dev, PTR_ERR(st->cnv_pwm), + "failed to get cnv pwm\n"); + + /* Preemptively disable the PWM in case it was enabled at boot */ + pwm_disable(st->cnv_pwm); + + st->clk_gate_pwm = devm_pwm_get(dev, "clk_gate"); + if (IS_ERR(st->clk_gate_pwm)) + return dev_err_probe(dev, PTR_ERR(st->clk_gate_pwm), + "failed to get clk_gate pwm\n"); + + /* Preemptively disable the PWM in case it was enabled at boot */ + pwm_disable(st->clk_gate_pwm); + + ref_clk = devm_clk_get_enabled(dev, NULL); + if (IS_ERR(ref_clk)) + return dev_err_probe(dev, PTR_ERR(ref_clk), + "failed to get ref_clk"); + + ref_clk_rate_hz = clk_get_rate(ref_clk); + if (!ref_clk_rate_hz) + return dev_err_probe(dev, -EINVAL, + "failed to get ref_clk rate"); + + st->ref_clk_rate_hz = ref_clk_rate_hz; + + return 0; +} + +/* + * There are three required input voltages for each device, plus two + * conditionally-optional (depending on part) REF and REFIN voltages + * where their validity depends upon the EN pin configuration. + * + * Power-up info for the device says to bring up vio, then vdd2, then + * vdd1, so list them in that order in the regulator_names array. + * + * The reference voltage source is determined like so: + * - internal reference: neither REF or REFIN is connected (invalid for + * AD796x) + * - internal buffer, external reference: REF not connected, REFIN + * connected + * - external reference: REF connected, REFIN not connected + */ +static int devm_ad7625_regulator_setup(struct device *dev, + struct ad7625_state *st) +{ + static const char * const regulator_names[] = { "vio", "vdd2", "vdd1" }; + int ret, ref_mv; + + ret = devm_regulator_bulk_get_enable(dev, ARRAY_SIZE(regulator_names), + regulator_names); + if (ret) + return ret; + + ret = devm_regulator_get_enable_read_voltage(dev, "ref"); + if (ret < 0 && ret != -ENODEV) + return dev_err_probe(dev, ret, "failed to get REF voltage\n"); + + ref_mv = ret == -ENODEV ? 0 : ret / 1000; + + ret = devm_regulator_get_enable_optional(dev, "refin"); + if (ret < 0 && ret != -ENODEV) + return dev_err_probe(dev, ret, "failed to get REFIN voltage\n"); + + st->have_refin = ret != -ENODEV; + + if (st->have_refin && !st->can_refin) + return dev_err_probe(dev, -EINVAL, + "REFIN provided in unsupported mode\n"); + + if (!st->info->has_internal_vref && !st->have_refin && !ref_mv) + return dev_err_probe(dev, -EINVAL, + "Need either REFIN or REF"); + + if (st->have_refin && ref_mv) + return dev_err_probe(dev, -EINVAL, + "cannot have both REFIN and REF supplies\n"); + + if (ref_mv == 4096 && !st->can_ref_4v096) + return dev_err_probe(dev, -EINVAL, + "REF is 4.096V in unsupported mode\n"); + + if (ref_mv == 5000 && !st->can_ref_5v) + return dev_err_probe(dev, -EINVAL, + "REF is 5V in unsupported mode\n"); + + st->vref_mv = ref_mv ?: AD7625_INTERNAL_REF_MV; + + return 0; +} + +static int ad7625_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct iio_dev *indio_dev; + struct ad7625_state *st; + struct clk *ref_clk; + int ret; + int default_sample_freq; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + + st->info = device_get_match_data(dev); + if (!st->info) + return dev_err_probe(dev, -EINVAL, "no chip info\n"); + + if (device_property_read_bool(dev, "adi,no-dco")) + return dev_err_probe(dev, -EINVAL, + "self-clocked mode not supported\n"); + + if (st->info->has_bandwidth_control) + ret = ad7625_parse_mode(dev, st, 4); + else + ret = ad7625_parse_mode(dev, st, 2); + + if (ret) + return ret; + + ret = devm_ad7625_regulator_setup(dev, st); + if (ret) + return ret; + + /* Set the device mode based on detected EN configuration. */ + if (!st->info->has_bandwidth_control) { + ad7625_set_en_gpios_for_vref(st, st->have_refin, st->vref_mv); + } else { + /* + * If neither sampling mode is available, then report an error, + * since the other modes are not useful defaults. + */ + if (st->can_wide_bandwidth) { + ret = ad7960_set_mode(st, AD7960_MODE_WIDE_BANDWIDTH, + st->have_refin, st->vref_mv); + } else if (st->can_narrow_bandwidth) { + ret = ad7960_set_mode(st, AD7960_MODE_NARROW_BANDWIDTH, + st->have_refin, st->vref_mv); + } else { + return dev_err_probe(dev, -EINVAL, + "couldn't set device to wide or narrow bandwidth modes\n"); + } + + if (ret) + return dev_err_probe(dev, -EINVAL, + "failed to set EN pins\n"); + } + + ret = devm_ad7625_pwm_get(dev, ref_clk, st); + if (ret) + return ret; + + indio_dev->channels = &st->info->chan_spec; + indio_dev->num_channels = 1; + indio_dev->name = st->info->name; + indio_dev->info = &ad7625_info; + indio_dev->setup_ops = &ad7625_buffer_setup_ops; + + st->back = devm_iio_backend_get(dev, NULL); + if (IS_ERR(st->back)) + return dev_err_probe(dev, PTR_ERR(st->back), + "failed to get IIO backend"); + + ret = devm_iio_backend_request_buffer(dev, st->back, indio_dev); + if (ret) + return ret; + + ret = devm_iio_backend_enable(dev, st->back); + if (ret) + return ret; + + /* + * Set the initial sampling frequency to the maximum, unless the + * AD796x device is limited to narrow bandwidth by EN2 == 1, in + * which case the sampling frequency should be limited to 2MSPS + */ + default_sample_freq = st->info->max_sample_rate_hz; + if (st->info->has_bandwidth_control && !st->can_wide_bandwidth) + default_sample_freq = AD7960_MAX_NBW_FREQ; + + ret = ad7625_set_sampling_freq(st, default_sample_freq); + if (ret) + dev_err_probe(dev, ret, + "failed to set valid sampling frequency\n"); + + return devm_iio_device_register(dev, indio_dev); +} + +static const struct of_device_id ad7625_of_match[] = { + { .compatible = "adi,ad7625", .data = &ad7625_chip_info }, + { .compatible = "adi,ad7626", .data = &ad7626_chip_info }, + { .compatible = "adi,ad7960", .data = &ad7960_chip_info }, + { .compatible = "adi,ad7961", .data = &ad7961_chip_info }, + { } +}; +MODULE_DEVICE_TABLE(of, ad7625_of_match); + +static const struct platform_device_id ad7625_device_ids[] = { + { .name = "ad7625", .driver_data = (kernel_ulong_t)&ad7625_chip_info }, + { .name = "ad7626", .driver_data = (kernel_ulong_t)&ad7626_chip_info }, + { .name = "ad7960", .driver_data = (kernel_ulong_t)&ad7960_chip_info }, + { .name = "ad7961", .driver_data = (kernel_ulong_t)&ad7961_chip_info }, + { } +}; +MODULE_DEVICE_TABLE(platform, ad7625_device_ids); + +static struct platform_driver ad7625_driver = { + .probe = ad7625_probe, + .driver = { + .name = "ad7625", + .of_match_table = ad7625_of_match, + }, + .id_table = ad7625_device_ids, +}; +module_platform_driver(ad7625_driver); + +MODULE_AUTHOR("Trevor Gamblin <tgamblin@xxxxxxxxxxxx>"); +MODULE_DESCRIPTION("Analog Devices AD7625 ADC"); +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_IMPORT_NS(IIO_BACKEND); -- 2.39.2
