mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-12-29 09:16:33 +00:00
iio: adc: ad7625: add driver
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. Reviewed-by: Nuno Sa <nuno.sa@analog.com> Signed-off-by: Trevor Gamblin <tgamblin@baylibre.com> Link: https://patch.msgid.link/20240909-ad7625_r1-v5-2-60a397768b25@baylibre.com Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Trevor Gamblin
Jonathan Cameron
parent
29301cc339
commit
b7ffd0fa65
@ -1335,6 +1335,7 @@ 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@analog.com>
|
||||
|
||||
@ -242,6 +242,22 @@ 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
|
||||
|
||||
@ -25,6 +25,7 @@ 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
|
||||
|
||||
684
drivers/iio/adc/ad7625.c
Normal file
684
drivers/iio/adc/ad7625.c
Normal file
@ -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_freq_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 */
|
||||
u32 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;
|
||||
u32 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_freq_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_freq_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_freq_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_freq_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, u32 freq)
|
||||
{
|
||||
u32 target;
|
||||
struct pwm_waveform clk_gate_wf = { }, cnv_wf = { };
|
||||
int ret;
|
||||
|
||||
target = DIV_ROUND_UP(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(st->ref_clk_rate_hz, freq);
|
||||
st->sampling_freq_hz = DIV_ROUND_CLOSEST(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->clk_gate_pwm);
|
||||
pwm_disable(st->cnv_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 ad7625_state *st)
|
||||
{
|
||||
struct clk *ref_clk;
|
||||
u32 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;
|
||||
int ret;
|
||||
u32 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, 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_freq_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@baylibre.com>");
|
||||
MODULE_DESCRIPTION("Analog Devices AD7625 ADC");
|
||||
MODULE_LICENSE("Dual BSD/GPL");
|
||||
MODULE_IMPORT_NS(IIO_BACKEND);
|
||||
Loading…
Reference in New Issue
Block a user