From: Nuno Sa <nuno.sa@xxxxxxxxxx> The AD9739A is a 14-bit, 2.5 GSPS high performance RF DACs that are capable of synthesizing wideband signals from DC up to 3 GHz. A dual-port, source synchronous, LVDS interface simplifies the digital interface with existing FGPA/ASIC technology. On-chip controllers are used to manage external and internal clock domain variations over temperature to ensure reliable data transfer from the host to the DAC core. Co-developed-by: Dragos Bogdan <dragos.bogdan@xxxxxxxxxx> Signed-off-by: Dragos Bogdan <dragos.bogdan@xxxxxxxxxx> Signed-off-by: Nuno Sa <nuno.sa@xxxxxxxxxx> --- Documentation/ABI/testing/sysfs-bus-iio-ad9739a | 19 + MAINTAINERS | 1 + drivers/iio/dac/Kconfig | 16 + drivers/iio/dac/Makefile | 1 + drivers/iio/dac/ad9739a.c | 463 ++++++++++++++++++++++++ 5 files changed, 500 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-bus-iio-ad9739a b/Documentation/ABI/testing/sysfs-bus-iio-ad9739a new file mode 100644 index 0000000000000..ed59299e6f8d9 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-iio-ad9739a @@ -0,0 +1,19 @@ +What: /sys/bus/iio/devices/iio:deviceX/out_voltageY_operating_mode +KernelVersion: 6.9 +Contact: linux-iio@xxxxxxxxxxxxxxx +Description: + DAC operating mode. One of the following modes can be selected: + + * normal: This is DAC normal mode. + * mixed-mode: In this mode the output is effectively chopped at + the DAC sample rate. This has the effect of + reducing the power of the fundamental signal while + increasing the power of the images centered around + the DAC sample rate, thus improving the output + power of these images. + +What: /sys/bus/iio/devices/iio:deviceX/out_voltageY_operating_mode_available +KernelVersion: 6.9 +Contact: linux-iio@xxxxxxxxxxxxxxx +Description: + Available operating modes. diff --git a/MAINTAINERS b/MAINTAINERS index 505f28dc6da68..8ad79cf705524 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1241,6 +1241,7 @@ L: linux-iio@xxxxxxxxxxxxxxx S: Supported W: https://ez.analog.com/linux-software-drivers F: Documentation/devicetree/bindings/iio/dac/adi,ad9739a.yaml +F: drivers/iio/dac/ad9739a.c ANALOG DEVICES INC ADA4250 DRIVER M: Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx> diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig index 7c0a8caa9a343..3c2bf620f00fb 100644 --- a/drivers/iio/dac/Kconfig +++ b/drivers/iio/dac/Kconfig @@ -131,6 +131,22 @@ config AD5624R_SPI Say yes here to build support for Analog Devices AD5624R, AD5644R and AD5664R converters (DAC). This driver uses the common SPI interface. +config AD9739A + tristate "Analog Devices AD9739A RF DAC spi driver" + depends on SPI || COMPILE_TEST + select REGMAP_SPI + select IIO_BACKEND + help + Say yes here to build support for Analog Devices AD9739A Digital-to + Analog Converter. + + The driver requires the assistance of the AXI DAC IP core to operate, + since SPI is used for configuration only, while data has to be + streamed into memory via DMA. + + To compile this driver as a module, choose M here: the module will be + called ad9739a. + config ADI_AXI_DAC tristate "Analog Devices Generic AXI DAC IP core driver" select IIO_BUFFER diff --git a/drivers/iio/dac/Makefile b/drivers/iio/dac/Makefile index 6bcaa65434b24..8432a81a19dc2 100644 --- a/drivers/iio/dac/Makefile +++ b/drivers/iio/dac/Makefile @@ -29,6 +29,7 @@ obj-$(CONFIG_AD5696_I2C) += ad5696-i2c.o obj-$(CONFIG_AD7293) += ad7293.o obj-$(CONFIG_AD7303) += ad7303.o obj-$(CONFIG_AD8801) += ad8801.o +obj-$(CONFIG_AD9739A) += ad9739a.o obj-$(CONFIG_ADI_AXI_DAC) += adi-axi-dac.o obj-$(CONFIG_CIO_DAC) += cio-dac.o obj-$(CONFIG_DPOT_DAC) += dpot-dac.o diff --git a/drivers/iio/dac/ad9739a.c b/drivers/iio/dac/ad9739a.c new file mode 100644 index 0000000000000..ff33120075bf6 --- /dev/null +++ b/drivers/iio/dac/ad9739a.c @@ -0,0 +1,463 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Analog Devices AD9739a SPI DAC driver + * + * Copyright 2015-2024 Analog Devices Inc. + */ +#include <linux/bitfield.h> +#include <linux/bits.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/gpio/consumer.h> +#include <linux/minmax.h> +#include <linux/module.h> +#include <linux/mod_devicetable.h> +#include <linux/property.h> +#include <linux/regmap.h> +#include <linux/spi/spi.h> +#include <linux/units.h> + +#include <linux/iio/backend.h> +#include <linux/iio/iio.h> +#include <linux/iio/types.h> + +#define AD9739A_REG_MODE 0 +#define AD9739A_RESET_MASK BIT(5) +#define AD9739A_REG_FSC_1 0x06 +#define AD9739A_REG_FSC_2 0x07 +#define AD9739A_FSC_MSB GENMASK(1, 0) +#define AD9739A_REG_DEC_CNT 0x8 +#define AD9739A_NORMAL_MODE 0 +#define AD9739A_MIXED_MODE 2 +#define AD9739A_DAC_DEC GENMASK(1, 0) +#define AD9739A_REG_LVDS_REC_CNT1 0x10 +#define AD9739A_RCVR_LOOP_EN_MASK GENMASK(1, 0) +#define AD9739A_REG_LVDS_REC_CNT4 0x13 +#define AD9739A_FINE_DEL_SKW_MASK GENMASK(3, 0) +#define AD9739A_REG_LVDS_REC_STAT9 0x21 +#define AD9739A_RCVR_TRACK_AND_LOCK (BIT(3) | BIT(0)) +#define AD9739A_REG_CROSS_CNT1 0x22 +#define AD9739A_REG_CROSS_CNT2 0x23 +#define AD9739A_REG_PHS_DET 0x24 +#define AD9739A_REG_MU_DUTY 0x25 +#define AD9739A_REG_MU_CNT1 0x26 +#define AD9739A_MU_EN_MASK BIT(0) +#define AD9739A_REG_MU_CNT2 0x27 +#define AD9739A_REG_MU_CNT3 0x28 +#define AD9739A_REG_MU_CNT4 0x29 +#define AD9739A_MU_CNT4_DEFAULT 0xcb +#define AD9739A_REG_MU_STAT1 0x2A +#define AD9739A_MU_LOCK_MASK BIT(0) +#define AD9739A_REG_ANA_CNT_1 0x32 +#define AD9739A_REG_ID 0x35 + +#define AD9739A_ID 0x24 +#define AD9739A_REG_IS_RESERVED(reg) \ + ((reg) == 0x5 || (reg) == 0x9 || (reg) == 0x0E || (reg) == 0x0D || \ + (reg) == 0x2B || (reg) == 0x2C || (reg) == 0x34) + +#define AD9739A_FSC_MIN 8580 +#define AD9739A_FSC_MAX 31700 +#define AD9739A_FSC_RANGE (AD9739A_FSC_MAX - AD9739A_FSC_MIN + 1) + +#define AD9739A_MIN_DAC_CLK (1600 * MEGA) +#define AD9739A_MAX_DAC_CLK (2500 * MEGA) +#define AD9739A_DAC_CLK_RANGE (AD9739A_MAX_DAC_CLK - AD9739A_MIN_DAC_CLK + 1) +/* as recommended by the datasheet */ +#define AD9739A_LOCK_N_TRIES 3 + +struct ad9739a_state { + struct iio_backend *back; + struct regmap *regmap; + unsigned long sample_rate; +}; + +static int ad9739a_oper_mode_get(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan) +{ + struct ad9739a_state *st = iio_priv(indio_dev); + u32 mode; + int ret; + + ret = regmap_read(st->regmap, AD9739A_REG_DEC_CNT, &mode); + if (ret) + return ret; + + mode = FIELD_GET(AD9739A_DAC_DEC, mode); + /* sanity check we get valid values from the HW */ + if (mode != AD9739A_NORMAL_MODE && mode != AD9739A_MIXED_MODE) + return -EIO; + if (!mode) + return AD9739A_NORMAL_MODE; + + /* + * We get 2 from the device but for IIO modes, that means 1. Hence the + * minus 1. + */ + return AD9739A_MIXED_MODE - 1; +} + +static int ad9739a_oper_mode_set(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, u32 mode) +{ + struct ad9739a_state *st = iio_priv(indio_dev); + + /* + * On the IIO interface we have 0 and 1 for mode. But for mixed_mode, we + * need to write 2 in the device. That's what the below check is about. + */ + if (mode == AD9739A_MIXED_MODE - 1) + mode = AD9739A_MIXED_MODE; + + return regmap_update_bits(st->regmap, AD9739A_REG_DEC_CNT, + AD9739A_DAC_DEC, mode); +} + +static int ad9739a_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct ad9739a_state *st = iio_priv(indio_dev); + + switch (mask) { + case IIO_CHAN_INFO_SAMP_FREQ: + *val = st->sample_rate; + *val2 = 0; + return IIO_VAL_INT_64; + default: + return -EINVAL; + } +} + +static int ad9739a_buffer_preenable(struct iio_dev *indio_dev) +{ + struct ad9739a_state *st = iio_priv(indio_dev); + + return iio_backend_data_source_set(st->back, 0, IIO_BACKEND_EXTERNAL); +} + +static int ad9739a_buffer_postdisable(struct iio_dev *indio_dev) +{ + struct ad9739a_state *st = iio_priv(indio_dev); + + return iio_backend_data_source_set(st->back, 0, + IIO_BACKEND_INTERNAL_CONTINUOS_WAVE); +} + +static bool ad9739a_reg_accessible(struct device *dev, unsigned int reg) +{ + if (AD9739A_REG_IS_RESERVED(reg)) + return false; + if (reg > AD9739A_REG_MU_STAT1 && reg < AD9739A_REG_ANA_CNT_1) + return false; + + return true; +} + +static int ad9739a_reset(struct device *dev, const struct ad9739a_state *st) +{ + struct gpio_desc *gpio; + int ret; + + gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH); + if (IS_ERR(gpio)) + return PTR_ERR(gpio); + if (gpio) { + /* minimum pulse width of 40ns */ + ndelay(40); + gpiod_set_value_cansleep(gpio, 0); + return 0; + } + + /* bring all registers to their default state */ + ret = regmap_set_bits(st->regmap, AD9739A_REG_MODE, AD9739A_RESET_MASK); + if (ret) + return ret; + + ndelay(40); + + return regmap_clear_bits(st->regmap, AD9739A_REG_MODE, + AD9739A_RESET_MASK); +} + +/* + * Recommended values (as per datasheet) for the dac clk common mode voltage + * and Mu controller. Look at table 29. + */ +static const struct reg_sequence ad9739a_clk_mu_ctrl[] = { + /* DAC clk common mode voltage */ + { AD9739A_REG_CROSS_CNT1, 0x0f }, + { AD9739A_REG_CROSS_CNT2, 0x0f }, + /* Mu controller configuration */ + { AD9739A_REG_PHS_DET, 0x30 }, + { AD9739A_REG_MU_DUTY, 0x80 }, + { AD9739A_REG_MU_CNT2, 0x44 }, + { AD9739A_REG_MU_CNT3, 0x6c }, +}; + +static int ad9739a_init(struct device *dev, const struct ad9739a_state *st) +{ + unsigned int i = 0, lock, fsc; + u32 fsc_raw; + int ret; + + ret = regmap_multi_reg_write(st->regmap, ad9739a_clk_mu_ctrl, + ARRAY_SIZE(ad9739a_clk_mu_ctrl)); + if (ret) + return ret; + + /* + * Try to get the Mu lock. Repeat the below steps AD9739A_LOCK_N_TRIES + * (as specified by the datasheet) until we get the lock. + */ + do { + ret = regmap_write(st->regmap, AD9739A_REG_MU_CNT4, + AD9739A_MU_CNT4_DEFAULT); + if (ret) + return ret; + + /* Enable the Mu controller search and track mode. */ + ret = regmap_set_bits(st->regmap, AD9739A_REG_MU_CNT1, + AD9739A_MU_EN_MASK); + if (ret) + return ret; + + /* Ensure the DLL loop is locked */ + ret = regmap_read_poll_timeout(st->regmap, AD9739A_REG_MU_STAT1, + lock, lock & AD9739A_MU_LOCK_MASK, + 0, 1000); + if (ret && ret != -ETIMEDOUT) + return ret; + } while (ret && ++i < AD9739A_LOCK_N_TRIES); + + if (i == AD9739A_LOCK_N_TRIES) + return dev_err_probe(dev, ret, "Mu lock timeout\n"); + + /* Receiver tracking and lock. Same deal as the Mu controller */ + i = 0; + do { + ret = regmap_update_bits(st->regmap, AD9739A_REG_LVDS_REC_CNT4, + AD9739A_FINE_DEL_SKW_MASK, + FIELD_PREP(AD9739A_FINE_DEL_SKW_MASK, 2)); + if (ret) + return ret; + + /* Disable the receiver and the loop. */ + ret = regmap_write(st->regmap, AD9739A_REG_LVDS_REC_CNT1, 0); + if (ret) + return ret; + + /* + * Re-enable the loop so it falls out of lock and begins the + * search/track routine again. + */ + ret = regmap_set_bits(st->regmap, AD9739A_REG_LVDS_REC_CNT1, + AD9739A_RCVR_LOOP_EN_MASK); + if (ret) + return ret; + + /* Ensure the DLL loop is locked */ + ret = regmap_read_poll_timeout(st->regmap, + AD9739A_REG_LVDS_REC_STAT9, lock, + lock == AD9739A_RCVR_TRACK_AND_LOCK, + 0, 1000); + if (ret && ret != -ETIMEDOUT) + return ret; + } while (ret && ++i < AD9739A_LOCK_N_TRIES); + + if (i == AD9739A_LOCK_N_TRIES) + return dev_err_probe(dev, ret, "Receiver lock timeout\n"); + + ret = device_property_read_u32(dev, "adi,full-scale-microamp", &fsc); + if (ret && ret == -EINVAL) + return 0; + if (ret) + return ret; + if (!in_range(fsc, AD9739A_FSC_MIN, AD9739A_FSC_RANGE)) + return dev_err_probe(dev, -EINVAL, + "Invalid full scale current(%u) [%u %u]\n", + fsc, AD9739A_FSC_MIN, AD9739A_FSC_MAX); + /* + * IOUTFS is given by + * Ioutfs = 0.0226 * FSC + 8.58 + * and is given in mA. Hence we'll have to multiply by 10 * MILLI in + * order to get rid of the fractional. + */ + fsc_raw = DIV_ROUND_CLOSEST(fsc * 10 - 85800, 226); + + ret = regmap_write(st->regmap, AD9739A_REG_FSC_1, fsc_raw & 0xff); + if (ret) + return ret; + + return regmap_update_bits(st->regmap, AD9739A_REG_FSC_2, + AD9739A_FSC_MSB, fsc_raw >> 8); +} + +static const char * const ad9739a_modes_avail[] = { "normal", "mixed-mode" }; + +static const struct iio_enum ad9739a_modes = { + .items = ad9739a_modes_avail, + .num_items = ARRAY_SIZE(ad9739a_modes_avail), + .get = ad9739a_oper_mode_get, + .set = ad9739a_oper_mode_set, +}; + +static const struct iio_chan_spec_ext_info ad9739a_ext_info[] = { + IIO_ENUM_AVAILABLE("operating_mode", IIO_SEPARATE, &ad9739a_modes), + IIO_ENUM("operating_mode", IIO_SEPARATE, &ad9739a_modes), + { } +}; + +/* + * The reason for having two different channels is because we have, in reality, + * two sources of data: + * ALTVOLTAGE: It's a Continuous Wave that's internally generated by the + * backend device. + * VOLTAGE: It's the typical data we can have in a DAC device and the source + * of it has nothing to do with the backend. The backend will only + * forward it into our data interface to be sent out. + */ +static struct iio_chan_spec ad9739a_channels[] = { + { + .type = IIO_ALTVOLTAGE, + .indexed = 1, + .output = 1, + .scan_index = -1, + }, + { + .type = IIO_VOLTAGE, + .indexed = 1, + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), + .output = 1, + .ext_info = ad9739a_ext_info, + .scan_type = { + .sign = 's', + .storagebits = 16, + .realbits = 16, + }, + } +}; + +static const struct iio_info ad9739a_info = { + .read_raw = ad9739a_read_raw, +}; + +static const struct iio_buffer_setup_ops ad9739a_buffer_setup_ops = { + .preenable = &ad9739a_buffer_preenable, + .postdisable = &ad9739a_buffer_postdisable, +}; + +static const struct regmap_config ad9739a_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .readable_reg = ad9739a_reg_accessible, + .writeable_reg = ad9739a_reg_accessible, + .max_register = AD9739A_REG_ID, +}; + +static int ad9739a_probe(struct spi_device *spi) +{ + struct device *dev = &spi->dev; + struct iio_dev *indio_dev; + struct ad9739a_state *st; + unsigned int id; + struct clk *clk; + int ret; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + + clk = devm_clk_get_enabled(dev, NULL); + if (IS_ERR(clk)) + return dev_err_probe(dev, PTR_ERR(clk), "Could not get clkin\n"); + + st->sample_rate = clk_get_rate(clk); + if (!in_range(st->sample_rate, AD9739A_MIN_DAC_CLK, + AD9739A_DAC_CLK_RANGE)) + return dev_err_probe(dev, -EINVAL, + "Invalid dac clk range(%lu) [%lu %lu]\n", + st->sample_rate, AD9739A_MIN_DAC_CLK, + AD9739A_MAX_DAC_CLK); + + st->regmap = devm_regmap_init_spi(spi, &ad9739a_regmap_config); + if (IS_ERR(st->regmap)) + return PTR_ERR(st->regmap); + + ret = regmap_read(st->regmap, AD9739A_REG_ID, &id); + if (ret) + return ret; + + if (id != AD9739A_ID) + dev_warn(dev, "Unrecognized CHIP_ID 0x%X", id); + + ret = ad9739a_reset(dev, st); + if (ret) + return ret; + + ret = ad9739a_init(dev, st); + if (ret) + return ret; + + st->back = devm_iio_backend_get(dev, NULL); + if (IS_ERR(st->back)) + return PTR_ERR(st->back); + + ret = devm_iio_backend_request_buffer(dev, st->back, indio_dev); + if (ret) + return ret; + + ret = iio_backend_extend_chan_spec(indio_dev, st->back, + &ad9739a_channels[0]); + if (ret) + return ret; + + ret = iio_backend_set_sampling_freq(st->back, 0, st->sample_rate); + if (ret) + return ret; + + ret = devm_iio_backend_enable(dev, st->back); + if (ret) + return ret; + + indio_dev->name = "ad9739a"; + indio_dev->info = &ad9739a_info; + indio_dev->channels = ad9739a_channels; + indio_dev->num_channels = ARRAY_SIZE(ad9739a_channels); + indio_dev->setup_ops = &ad9739a_buffer_setup_ops; + + return devm_iio_device_register(&spi->dev, indio_dev); +} + +static const struct of_device_id ad9739a_of_match[] = { + { .compatible = "adi,ad9739a" }, + {} +}; +MODULE_DEVICE_TABLE(of, ad9739a_of_match); + +static const struct spi_device_id ad9739a_id[] = { + {"ad9739a"}, + {} +}; +MODULE_DEVICE_TABLE(spi, ad9739a_id); + +static struct spi_driver ad9739a_driver = { + .driver = { + .name = "ad9739a", + .of_match_table = ad9739a_of_match, + }, + .probe = ad9739a_probe, + .id_table = ad9739a_id, +}; +module_spi_driver(ad9739a_driver); + +MODULE_AUTHOR("Dragos Bogdan <dragos.bogdan@xxxxxxxxxx>"); +MODULE_AUTHOR("Nuno Sa <nuno.sa@xxxxxxxxxx>"); +MODULE_DESCRIPTION("Analog Devices AD9739 DAC"); +MODULE_LICENSE("GPL"); +MODULE_IMPORT_NS(IIO_BACKEND); -- 2.44.0
