diff options
Diffstat (limited to 'drivers/iio/dac/ad3552r.c')
| -rw-r--r-- | drivers/iio/dac/ad3552r.c | 700 |
1 files changed, 700 insertions, 0 deletions
diff --git a/drivers/iio/dac/ad3552r.c b/drivers/iio/dac/ad3552r.c new file mode 100644 index 000000000000..93c33bc3e1be --- /dev/null +++ b/drivers/iio/dac/ad3552r.c @@ -0,0 +1,700 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Analog Devices AD3552R + * Digital to Analog converter driver + * + * Copyright 2021 Analog Devices Inc. + */ +#include <linux/unaligned.h> +#include <linux/bitfield.h> +#include <linux/device.h> +#include <linux/iio/triggered_buffer.h> +#include <linux/iio/trigger_consumer.h> +#include <linux/iopoll.h> +#include <linux/kernel.h> +#include <linux/spi/spi.h> + +#include "ad3552r.h" + +struct ad3552r_desc { + const struct ad3552r_model_data *model_data; + /* Used to look the spi bus for atomic operations where needed */ + struct mutex lock; + struct gpio_desc *gpio_reset; + struct gpio_desc *gpio_ldac; + struct spi_device *spi; + struct ad3552r_ch_data ch_data[AD3552R_MAX_CH]; + struct iio_chan_spec channels[AD3552R_MAX_CH + 1]; + unsigned long enabled_ch; + unsigned int num_ch; +}; + +static u8 _ad3552r_reg_len(u8 addr) +{ + switch (addr) { + case AD3552R_REG_ADDR_HW_LDAC_16B: + case AD3552R_REG_ADDR_CH_SELECT_16B: + case AD3552R_REG_ADDR_SW_LDAC_16B: + case AD3552R_REG_ADDR_HW_LDAC_24B: + case AD3552R_REG_ADDR_CH_SELECT_24B: + case AD3552R_REG_ADDR_SW_LDAC_24B: + return 1; + default: + break; + } + + if (addr > AD3552R_REG_ADDR_HW_LDAC_24B) + return 3; + if (addr > AD3552R_REG_ADDR_HW_LDAC_16B) + return 2; + + return 1; +} + +/* SPI transfer to device */ +static int ad3552r_transfer(struct ad3552r_desc *dac, u8 addr, u32 len, + u8 *data, bool is_read) +{ + /* Maximum transfer: Addr (1B) + 2 * (Data Reg (3B)) + SW LDAC(1B) */ + u8 buf[8]; + + buf[0] = addr & AD3552R_ADDR_MASK; + buf[0] |= is_read ? AD3552R_READ_BIT : 0; + if (is_read) + return spi_write_then_read(dac->spi, buf, 1, data, len); + + memcpy(buf + 1, data, len); + return spi_write_then_read(dac->spi, buf, len + 1, NULL, 0); +} + +static int ad3552r_write_reg(struct ad3552r_desc *dac, u8 addr, u16 val) +{ + u8 reg_len; + u8 buf[AD3552R_MAX_REG_SIZE] = { 0 }; + + reg_len = _ad3552r_reg_len(addr); + if (reg_len == 2) + /* Only DAC register are 2 bytes wide */ + val &= AD3552R_MASK_DAC_12B; + if (reg_len == 1) + buf[0] = val & 0xFF; + else + /* reg_len can be 2 or 3, but 3rd bytes needs to be set to 0 */ + put_unaligned_be16(val, buf); + + return ad3552r_transfer(dac, addr, reg_len, buf, false); +} + +static int ad3552r_read_reg(struct ad3552r_desc *dac, u8 addr, u16 *val) +{ + int err; + u8 reg_len, buf[AD3552R_MAX_REG_SIZE] = { 0 }; + + reg_len = _ad3552r_reg_len(addr); + err = ad3552r_transfer(dac, addr, reg_len, buf, true); + if (err) + return err; + + if (reg_len == 1) + *val = buf[0]; + else + /* reg_len can be 2 or 3, but only first 2 bytes are relevant */ + *val = get_unaligned_be16(buf); + + return 0; +} + +/* Update field of a register, shift val if needed */ +static int ad3552r_update_reg_field(struct ad3552r_desc *dac, u8 addr, u16 mask, + u16 val) +{ + int ret; + u16 reg; + + ret = ad3552r_read_reg(dac, addr, ®); + if (ret < 0) + return ret; + + reg &= ~mask; + reg |= val; + + return ad3552r_write_reg(dac, addr, reg); +} + +#define AD3552R_CH_DAC(_idx) ((struct iio_chan_spec) { \ + .type = IIO_VOLTAGE, \ + .output = true, \ + .indexed = true, \ + .channel = _idx, \ + .scan_index = _idx, \ + .scan_type = { \ + .sign = 'u', \ + .realbits = 16, \ + .storagebits = 16, \ + .endianness = IIO_BE, \ + }, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ + BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_ENABLE) | \ + BIT(IIO_CHAN_INFO_OFFSET), \ +}) + +static int ad3552r_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, + int *val2, + long mask) +{ + struct ad3552r_desc *dac = iio_priv(indio_dev); + u16 tmp_val; + int err; + u8 ch = chan->channel; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + mutex_lock(&dac->lock); + err = ad3552r_read_reg(dac, AD3552R_REG_ADDR_CH_DAC_24B(ch), + &tmp_val); + mutex_unlock(&dac->lock); + if (err < 0) + return err; + *val = tmp_val; + return IIO_VAL_INT; + case IIO_CHAN_INFO_ENABLE: + mutex_lock(&dac->lock); + err = ad3552r_read_reg(dac, AD3552R_REG_ADDR_POWERDOWN_CONFIG, + &tmp_val); + mutex_unlock(&dac->lock); + if (err < 0) + return err; + *val = !((tmp_val & AD3552R_MASK_CH_DAC_POWERDOWN(ch)) >> + __ffs(AD3552R_MASK_CH_DAC_POWERDOWN(ch))); + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + *val = dac->ch_data[ch].scale_int; + *val2 = dac->ch_data[ch].scale_dec; + return IIO_VAL_INT_PLUS_MICRO; + case IIO_CHAN_INFO_OFFSET: + *val = dac->ch_data[ch].offset_int; + *val2 = dac->ch_data[ch].offset_dec; + return IIO_VAL_INT_PLUS_MICRO; + default: + return -EINVAL; + } +} + +static int ad3552r_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, + int val2, + long mask) +{ + struct ad3552r_desc *dac = iio_priv(indio_dev); + int err; + + mutex_lock(&dac->lock); + switch (mask) { + case IIO_CHAN_INFO_RAW: + err = ad3552r_write_reg(dac, + AD3552R_REG_ADDR_CH_DAC_24B(chan->channel), + val); + break; + case IIO_CHAN_INFO_ENABLE: + if (chan->channel == 0) + val = FIELD_PREP(AD3552R_MASK_CH_DAC_POWERDOWN(0), !val); + else + val = FIELD_PREP(AD3552R_MASK_CH_DAC_POWERDOWN(1), !val); + + err = ad3552r_update_reg_field(dac, AD3552R_REG_ADDR_POWERDOWN_CONFIG, + AD3552R_MASK_CH_DAC_POWERDOWN(chan->channel), + val); + break; + default: + err = -EINVAL; + break; + } + mutex_unlock(&dac->lock); + + return err; +} + +static const struct iio_info ad3552r_iio_info = { + .read_raw = ad3552r_read_raw, + .write_raw = ad3552r_write_raw +}; + +static int32_t ad3552r_trigger_hw_ldac(struct gpio_desc *ldac) +{ + gpiod_set_value_cansleep(ldac, 0); + usleep_range(AD3552R_LDAC_PULSE_US, AD3552R_LDAC_PULSE_US + 10); + gpiod_set_value_cansleep(ldac, 1); + + return 0; +} + +static int ad3552r_write_all_channels(struct ad3552r_desc *dac, u8 *data) +{ + int err, len; + u8 addr, buff[AD3552R_MAX_CH * AD3552R_MAX_REG_SIZE + 1]; + + addr = AD3552R_REG_ADDR_CH_INPUT_24B(1); + /* CH1 */ + memcpy(buff, data + 2, 2); + buff[2] = 0; + /* CH0 */ + memcpy(buff + 3, data, 2); + buff[5] = 0; + len = 6; + if (!dac->gpio_ldac) { + /* Software LDAC */ + buff[6] = AD3552R_MASK_ALL_CH; + ++len; + } + err = ad3552r_transfer(dac, addr, len, buff, false); + if (err) + return err; + + if (dac->gpio_ldac) + return ad3552r_trigger_hw_ldac(dac->gpio_ldac); + + return 0; +} + +static int ad3552r_write_codes(struct ad3552r_desc *dac, u32 mask, u8 *data) +{ + int err; + u8 addr, buff[AD3552R_MAX_REG_SIZE]; + + if (mask == AD3552R_MASK_ALL_CH) { + if (memcmp(data, data + 2, 2) != 0) + return ad3552r_write_all_channels(dac, data); + + addr = AD3552R_REG_ADDR_INPUT_PAGE_MASK_24B; + } else { + addr = AD3552R_REG_ADDR_CH_INPUT_24B(__ffs(mask)); + } + + memcpy(buff, data, 2); + buff[2] = 0; + err = ad3552r_transfer(dac, addr, 3, data, false); + if (err) + return err; + + if (dac->gpio_ldac) + return ad3552r_trigger_hw_ldac(dac->gpio_ldac); + + return ad3552r_write_reg(dac, AD3552R_REG_ADDR_SW_LDAC_24B, mask); +} + +static irqreturn_t ad3552r_trigger_handler(int irq, void *p) +{ + struct iio_poll_func *pf = p; + struct iio_dev *indio_dev = pf->indio_dev; + struct iio_buffer *buf = indio_dev->buffer; + struct ad3552r_desc *dac = iio_priv(indio_dev); + /* Maximum size of a scan */ + u8 buff[AD3552R_MAX_CH * AD3552R_MAX_REG_SIZE] = { }; + int err; + + err = iio_pop_from_buffer(buf, buff); + if (err) + goto end; + + mutex_lock(&dac->lock); + ad3552r_write_codes(dac, *indio_dev->active_scan_mask, buff); + mutex_unlock(&dac->lock); +end: + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + +static int ad3552r_check_scratch_pad(struct ad3552r_desc *dac) +{ + const u16 val1 = AD3552R_SCRATCH_PAD_TEST_VAL1; + const u16 val2 = AD3552R_SCRATCH_PAD_TEST_VAL2; + u16 val; + int err; + + err = ad3552r_write_reg(dac, AD3552R_REG_ADDR_SCRATCH_PAD, val1); + if (err < 0) + return err; + + err = ad3552r_read_reg(dac, AD3552R_REG_ADDR_SCRATCH_PAD, &val); + if (err < 0) + return err; + + if (val1 != val) + return -ENODEV; + + err = ad3552r_write_reg(dac, AD3552R_REG_ADDR_SCRATCH_PAD, val2); + if (err < 0) + return err; + + err = ad3552r_read_reg(dac, AD3552R_REG_ADDR_SCRATCH_PAD, &val); + if (err < 0) + return err; + + if (val2 != val) + return -ENODEV; + + return 0; +} + +struct reg_addr_pool { + struct ad3552r_desc *dac; + u8 addr; +}; + +static int ad3552r_read_reg_wrapper(struct reg_addr_pool *addr) +{ + int err; + u16 val; + + err = ad3552r_read_reg(addr->dac, addr->addr, &val); + if (err) + return err; + + return val; +} + +static int ad3552r_reset(struct ad3552r_desc *dac) +{ + struct reg_addr_pool addr; + int ret; + int val; + + dac->gpio_reset = devm_gpiod_get_optional(&dac->spi->dev, "reset", + GPIOD_OUT_LOW); + if (IS_ERR(dac->gpio_reset)) + return dev_err_probe(&dac->spi->dev, PTR_ERR(dac->gpio_reset), + "Error while getting gpio reset"); + + if (dac->gpio_reset) { + /* Perform hardware reset */ + usleep_range(10, 20); + gpiod_set_value_cansleep(dac->gpio_reset, 1); + } else { + /* Perform software reset if no GPIO provided */ + ret = ad3552r_update_reg_field(dac, + AD3552R_REG_ADDR_INTERFACE_CONFIG_A, + AD3552R_MASK_SOFTWARE_RESET, + AD3552R_MASK_SOFTWARE_RESET); + if (ret < 0) + return ret; + + } + + addr.dac = dac; + addr.addr = AD3552R_REG_ADDR_INTERFACE_CONFIG_B; + ret = readx_poll_timeout(ad3552r_read_reg_wrapper, &addr, val, + val == AD3552R_DEFAULT_CONFIG_B_VALUE || + val < 0, + 5000, 50000); + if (val < 0) + ret = val; + if (ret) { + dev_err(&dac->spi->dev, "Error while resetting"); + return ret; + } + + ret = readx_poll_timeout(ad3552r_read_reg_wrapper, &addr, val, + !(val & AD3552R_MASK_INTERFACE_NOT_READY) || + val < 0, + 5000, 50000); + if (val < 0) + ret = val; + if (ret) { + dev_err(&dac->spi->dev, "Error while resetting"); + return ret; + } + + /* Clear reset error flag, see ad3552r manual, rev B table 38. */ + ret = ad3552r_write_reg(dac, AD3552R_REG_ADDR_ERR_STATUS, + AD3552R_MASK_RESET_STATUS); + if (ret) + return ret; + + return ad3552r_update_reg_field(dac, + AD3552R_REG_ADDR_INTERFACE_CONFIG_A, + AD3552R_MASK_ADDR_ASCENSION, + FIELD_PREP(AD3552R_MASK_ADDR_ASCENSION, val)); +} + +static int ad3552r_configure_custom_gain(struct ad3552r_desc *dac, + struct fwnode_handle *child, + u32 ch) +{ + struct device *dev = &dac->spi->dev; + int err; + u8 addr; + u16 reg; + + err = ad3552r_get_custom_gain(dev, child, + &dac->ch_data[ch].p, + &dac->ch_data[ch].n, + &dac->ch_data[ch].rfb, + &dac->ch_data[ch].gain_offset); + if (err) + return err; + + dac->ch_data[ch].range_override = 1; + + addr = AD3552R_REG_ADDR_CH_GAIN(ch); + err = ad3552r_write_reg(dac, addr, + abs((s32)dac->ch_data[ch].gain_offset) & + AD3552R_MASK_CH_OFFSET_BITS_0_7); + if (err) + return dev_err_probe(dev, err, "Error writing register\n"); + + reg = ad3552r_calc_custom_gain(dac->ch_data[ch].p, dac->ch_data[ch].n, + dac->ch_data[ch].gain_offset); + + err = ad3552r_write_reg(dac, addr, reg); + if (err) + return dev_err_probe(dev, err, "Error writing register\n"); + + return 0; +} + +static int ad3552r_configure_device(struct ad3552r_desc *dac) +{ + struct device *dev = &dac->spi->dev; + int err, cnt = 0; + u32 val, ch; + + dac->gpio_ldac = devm_gpiod_get_optional(dev, "ldac", GPIOD_OUT_HIGH); + if (IS_ERR(dac->gpio_ldac)) + return dev_err_probe(dev, PTR_ERR(dac->gpio_ldac), + "Error getting gpio ldac"); + + err = ad3552r_get_ref_voltage(dev, &val); + if (err < 0) + return err; + + err = ad3552r_update_reg_field(dac, + AD3552R_REG_ADDR_SH_REFERENCE_CONFIG, + AD3552R_MASK_REFERENCE_VOLTAGE_SEL, + FIELD_PREP(AD3552R_MASK_REFERENCE_VOLTAGE_SEL, val)); + if (err) + return err; + + err = ad3552r_get_drive_strength(dev, &val); + if (!err) { + err = ad3552r_update_reg_field(dac, + AD3552R_REG_ADDR_INTERFACE_CONFIG_D, + AD3552R_MASK_SDO_DRIVE_STRENGTH, + FIELD_PREP(AD3552R_MASK_SDO_DRIVE_STRENGTH, val)); + if (err) + return err; + } + + dac->num_ch = device_get_child_node_count(dev); + if (!dac->num_ch) { + dev_err(dev, "No channels defined\n"); + return -ENODEV; + } + + device_for_each_child_node_scoped(dev, child) { + err = fwnode_property_read_u32(child, "reg", &ch); + if (err) + return dev_err_probe(dev, err, + "mandatory reg property missing\n"); + if (ch >= dac->model_data->num_hw_channels) + return dev_err_probe(dev, -EINVAL, + "reg must be less than %d\n", + dac->model_data->num_hw_channels); + + err = ad3552r_get_output_range(dev, dac->model_data, + child, &val); + if (err && err != -ENOENT) + return err; + + if (!err) { + if (ch == 0) + val = FIELD_PREP(AD3552R_MASK_CH_OUTPUT_RANGE_SEL(0), val); + else + val = FIELD_PREP(AD3552R_MASK_CH_OUTPUT_RANGE_SEL(1), val); + + err = ad3552r_update_reg_field(dac, + AD3552R_REG_ADDR_CH0_CH1_OUTPUT_RANGE, + AD3552R_MASK_CH_OUTPUT_RANGE_SEL(ch), + val); + if (err) + return err; + + dac->ch_data[ch].range = val; + } else if (dac->model_data->requires_output_range) { + return dev_err_probe(dev, -EINVAL, + "adi,output-range-microvolt is required for %s\n", + dac->model_data->model_name); + } else { + err = ad3552r_configure_custom_gain(dac, child, ch); + if (err) + return err; + } + + ad3552r_calc_gain_and_offset(&dac->ch_data[ch], dac->model_data); + dac->enabled_ch |= BIT(ch); + + if (ch == 0) + val = FIELD_PREP(AD3552R_MASK_CH(0), 1); + else + val = FIELD_PREP(AD3552R_MASK_CH(1), 1); + + err = ad3552r_update_reg_field(dac, + AD3552R_REG_ADDR_CH_SELECT_16B, + AD3552R_MASK_CH(ch), val); + if (err < 0) + return err; + + dac->channels[cnt] = AD3552R_CH_DAC(ch); + ++cnt; + + } + + /* Disable unused channels */ + for_each_clear_bit(ch, &dac->enabled_ch, + dac->model_data->num_hw_channels) { + if (ch == 0) + val = FIELD_PREP(AD3552R_MASK_CH_AMPLIFIER_POWERDOWN(0), 1); + else + val = FIELD_PREP(AD3552R_MASK_CH_AMPLIFIER_POWERDOWN(1), 1); + + err = ad3552r_update_reg_field(dac, + AD3552R_REG_ADDR_POWERDOWN_CONFIG, + AD3552R_MASK_CH_AMPLIFIER_POWERDOWN(ch), + val); + if (err) + return err; + } + + dac->num_ch = cnt; + + return 0; +} + +static int ad3552r_init(struct ad3552r_desc *dac) +{ + int err; + u16 val, id; + + err = ad3552r_reset(dac); + if (err) { + dev_err(&dac->spi->dev, "Reset failed\n"); + return err; + } + + err = ad3552r_check_scratch_pad(dac); + if (err) { + dev_err(&dac->spi->dev, "Scratch pad test failed\n"); + return err; + } + + err = ad3552r_read_reg(dac, AD3552R_REG_ADDR_PRODUCT_ID_L, &val); + if (err) { + dev_err(&dac->spi->dev, "Fail read PRODUCT_ID_L\n"); + return err; + } + + id = val; + err = ad3552r_read_reg(dac, AD3552R_REG_ADDR_PRODUCT_ID_H, &val); + if (err) { + dev_err(&dac->spi->dev, "Fail read PRODUCT_ID_H\n"); + return err; + } + + id |= val << 8; + if (id != dac->model_data->chip_id) { + dev_err(&dac->spi->dev, "Product id not matching\n"); + return -ENODEV; + } + + return ad3552r_configure_device(dac); +} + +static int ad3552r_probe(struct spi_device *spi) +{ + struct ad3552r_desc *dac; + struct iio_dev *indio_dev; + int err; + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*dac)); + if (!indio_dev) + return -ENOMEM; + + dac = iio_priv(indio_dev); + dac->spi = spi; + dac->model_data = spi_get_device_match_data(spi); + if (!dac->model_data) + return -EINVAL; + + mutex_init(&dac->lock); + + err = ad3552r_init(dac); + if (err) + return err; + + /* Config triggered buffer device */ + indio_dev->name = dac->model_data->model_name; + indio_dev->dev.parent = &spi->dev; + indio_dev->info = &ad3552r_iio_info; + indio_dev->num_channels = dac->num_ch; + indio_dev->channels = dac->channels; + indio_dev->modes = INDIO_DIRECT_MODE; + + err = devm_iio_triggered_buffer_setup_ext(&indio_dev->dev, indio_dev, NULL, + &ad3552r_trigger_handler, + IIO_BUFFER_DIRECTION_OUT, + NULL, + NULL); + if (err) + return err; + + return devm_iio_device_register(&spi->dev, indio_dev); +} + +static const struct spi_device_id ad3552r_id[] = { + { + .name = "ad3541r", + .driver_data = (kernel_ulong_t)&ad3541r_model_data + }, + { + .name = "ad3542r", + .driver_data = (kernel_ulong_t)&ad3542r_model_data + }, + { + .name = "ad3551r", + .driver_data = (kernel_ulong_t)&ad3551r_model_data + }, + { + .name = "ad3552r", + .driver_data = (kernel_ulong_t)&ad3552r_model_data + }, + { } +}; +MODULE_DEVICE_TABLE(spi, ad3552r_id); + +static const struct of_device_id ad3552r_of_match[] = { + { .compatible = "adi,ad3541r", .data = &ad3541r_model_data }, + { .compatible = "adi,ad3542r", .data = &ad3542r_model_data }, + { .compatible = "adi,ad3551r", .data = &ad3551r_model_data }, + { .compatible = "adi,ad3552r", .data = &ad3552r_model_data }, + { } +}; +MODULE_DEVICE_TABLE(of, ad3552r_of_match); + +static struct spi_driver ad3552r_driver = { + .driver = { + .name = "ad3552r", + .of_match_table = ad3552r_of_match, + }, + .probe = ad3552r_probe, + .id_table = ad3552r_id +}; +module_spi_driver(ad3552r_driver); + +MODULE_AUTHOR("Mihail Chindris <mihail.chindris@analog.com>"); +MODULE_DESCRIPTION("Analog Device AD3552R DAC"); +MODULE_LICENSE("GPL v2"); +MODULE_IMPORT_NS("IIO_AD3552R"); |