diff options
Diffstat (limited to 'drivers/iio/dac/ad3552r.c')
-rw-r--r-- | drivers/iio/dac/ad3552r.c | 1138 |
1 files changed, 1138 insertions, 0 deletions
diff --git a/drivers/iio/dac/ad3552r.c b/drivers/iio/dac/ad3552r.c new file mode 100644 index 000000000..a492e8f2f --- /dev/null +++ b/drivers/iio/dac/ad3552r.c @@ -0,0 +1,1138 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Analog Devices AD3552R + * Digital to Analog converter driver + * + * Copyright 2021 Analog Devices Inc. + */ +#include <asm/unaligned.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/regulator/consumer.h> +#include <linux/spi/spi.h> + +/* Register addresses */ +/* Primary address space */ +#define AD3552R_REG_ADDR_INTERFACE_CONFIG_A 0x00 +#define AD3552R_MASK_SOFTWARE_RESET (BIT(7) | BIT(0)) +#define AD3552R_MASK_ADDR_ASCENSION BIT(5) +#define AD3552R_MASK_SDO_ACTIVE BIT(4) +#define AD3552R_REG_ADDR_INTERFACE_CONFIG_B 0x01 +#define AD3552R_MASK_SINGLE_INST BIT(7) +#define AD3552R_MASK_SHORT_INSTRUCTION BIT(3) +#define AD3552R_REG_ADDR_DEVICE_CONFIG 0x02 +#define AD3552R_MASK_DEVICE_STATUS(n) BIT(4 + (n)) +#define AD3552R_MASK_CUSTOM_MODES GENMASK(3, 2) +#define AD3552R_MASK_OPERATING_MODES GENMASK(1, 0) +#define AD3552R_REG_ADDR_CHIP_TYPE 0x03 +#define AD3552R_MASK_CLASS GENMASK(7, 0) +#define AD3552R_REG_ADDR_PRODUCT_ID_L 0x04 +#define AD3552R_REG_ADDR_PRODUCT_ID_H 0x05 +#define AD3552R_REG_ADDR_CHIP_GRADE 0x06 +#define AD3552R_MASK_GRADE GENMASK(7, 4) +#define AD3552R_MASK_DEVICE_REVISION GENMASK(3, 0) +#define AD3552R_REG_ADDR_SCRATCH_PAD 0x0A +#define AD3552R_REG_ADDR_SPI_REVISION 0x0B +#define AD3552R_REG_ADDR_VENDOR_L 0x0C +#define AD3552R_REG_ADDR_VENDOR_H 0x0D +#define AD3552R_REG_ADDR_STREAM_MODE 0x0E +#define AD3552R_MASK_LENGTH GENMASK(7, 0) +#define AD3552R_REG_ADDR_TRANSFER_REGISTER 0x0F +#define AD3552R_MASK_MULTI_IO_MODE GENMASK(7, 6) +#define AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE BIT(2) +#define AD3552R_REG_ADDR_INTERFACE_CONFIG_C 0x10 +#define AD3552R_MASK_CRC_ENABLE (GENMASK(7, 6) |\ + GENMASK(1, 0)) +#define AD3552R_MASK_STRICT_REGISTER_ACCESS BIT(5) +#define AD3552R_REG_ADDR_INTERFACE_STATUS_A 0x11 +#define AD3552R_MASK_INTERFACE_NOT_READY BIT(7) +#define AD3552R_MASK_CLOCK_COUNTING_ERROR BIT(5) +#define AD3552R_MASK_INVALID_OR_NO_CRC BIT(3) +#define AD3552R_MASK_WRITE_TO_READ_ONLY_REGISTER BIT(2) +#define AD3552R_MASK_PARTIAL_REGISTER_ACCESS BIT(1) +#define AD3552R_MASK_REGISTER_ADDRESS_INVALID BIT(0) +#define AD3552R_REG_ADDR_INTERFACE_CONFIG_D 0x14 +#define AD3552R_MASK_ALERT_ENABLE_PULLUP BIT(6) +#define AD3552R_MASK_MEM_CRC_EN BIT(4) +#define AD3552R_MASK_SDO_DRIVE_STRENGTH GENMASK(3, 2) +#define AD3552R_MASK_DUAL_SPI_SYNCHROUNOUS_EN BIT(1) +#define AD3552R_MASK_SPI_CONFIG_DDR BIT(0) +#define AD3552R_REG_ADDR_SH_REFERENCE_CONFIG 0x15 +#define AD3552R_MASK_IDUMP_FAST_MODE BIT(6) +#define AD3552R_MASK_SAMPLE_HOLD_DIFFERENTIAL_USER_EN BIT(5) +#define AD3552R_MASK_SAMPLE_HOLD_USER_TRIM GENMASK(4, 3) +#define AD3552R_MASK_SAMPLE_HOLD_USER_ENABLE BIT(2) +#define AD3552R_MASK_REFERENCE_VOLTAGE_SEL GENMASK(1, 0) +#define AD3552R_REG_ADDR_ERR_ALARM_MASK 0x16 +#define AD3552R_MASK_REF_RANGE_ALARM BIT(6) +#define AD3552R_MASK_CLOCK_COUNT_ERR_ALARM BIT(5) +#define AD3552R_MASK_MEM_CRC_ERR_ALARM BIT(4) +#define AD3552R_MASK_SPI_CRC_ERR_ALARM BIT(3) +#define AD3552R_MASK_WRITE_TO_READ_ONLY_ALARM BIT(2) +#define AD3552R_MASK_PARTIAL_REGISTER_ACCESS_ALARM BIT(1) +#define AD3552R_MASK_REGISTER_ADDRESS_INVALID_ALARM BIT(0) +#define AD3552R_REG_ADDR_ERR_STATUS 0x17 +#define AD3552R_MASK_REF_RANGE_ERR_STATUS BIT(6) +#define AD3552R_MASK_DUAL_SPI_STREAM_EXCEEDS_DAC_ERR_STATUS BIT(5) +#define AD3552R_MASK_MEM_CRC_ERR_STATUS BIT(4) +#define AD3552R_MASK_RESET_STATUS BIT(0) +#define AD3552R_REG_ADDR_POWERDOWN_CONFIG 0x18 +#define AD3552R_MASK_CH_DAC_POWERDOWN(ch) BIT(4 + (ch)) +#define AD3552R_MASK_CH_AMPLIFIER_POWERDOWN(ch) BIT(ch) +#define AD3552R_REG_ADDR_CH0_CH1_OUTPUT_RANGE 0x19 +#define AD3552R_MASK_CH_OUTPUT_RANGE_SEL(ch) ((ch) ? GENMASK(7, 4) :\ + GENMASK(3, 0)) +#define AD3552R_REG_ADDR_CH_OFFSET(ch) (0x1B + (ch) * 2) +#define AD3552R_MASK_CH_OFFSET_BITS_0_7 GENMASK(7, 0) +#define AD3552R_REG_ADDR_CH_GAIN(ch) (0x1C + (ch) * 2) +#define AD3552R_MASK_CH_RANGE_OVERRIDE BIT(7) +#define AD3552R_MASK_CH_GAIN_SCALING_N GENMASK(6, 5) +#define AD3552R_MASK_CH_GAIN_SCALING_P GENMASK(4, 3) +#define AD3552R_MASK_CH_OFFSET_POLARITY BIT(2) +#define AD3552R_MASK_CH_OFFSET_BIT_8 BIT(0) +/* + * Secondary region + * For multibyte registers specify the highest address because the access is + * done in descending order + */ +#define AD3552R_SECONDARY_REGION_START 0x28 +#define AD3552R_REG_ADDR_HW_LDAC_16B 0x28 +#define AD3552R_REG_ADDR_CH_DAC_16B(ch) (0x2C - (1 - ch) * 2) +#define AD3552R_REG_ADDR_DAC_PAGE_MASK_16B 0x2E +#define AD3552R_REG_ADDR_CH_SELECT_16B 0x2F +#define AD3552R_REG_ADDR_INPUT_PAGE_MASK_16B 0x31 +#define AD3552R_REG_ADDR_SW_LDAC_16B 0x32 +#define AD3552R_REG_ADDR_CH_INPUT_16B(ch) (0x36 - (1 - ch) * 2) +/* 3 bytes registers */ +#define AD3552R_REG_START_24B 0x37 +#define AD3552R_REG_ADDR_HW_LDAC_24B 0x37 +#define AD3552R_REG_ADDR_CH_DAC_24B(ch) (0x3D - (1 - ch) * 3) +#define AD3552R_REG_ADDR_DAC_PAGE_MASK_24B 0x40 +#define AD3552R_REG_ADDR_CH_SELECT_24B 0x41 +#define AD3552R_REG_ADDR_INPUT_PAGE_MASK_24B 0x44 +#define AD3552R_REG_ADDR_SW_LDAC_24B 0x45 +#define AD3552R_REG_ADDR_CH_INPUT_24B(ch) (0x4B - (1 - ch) * 3) + +/* Useful defines */ +#define AD3552R_NUM_CH 2 +#define AD3552R_MASK_CH(ch) BIT(ch) +#define AD3552R_MASK_ALL_CH GENMASK(1, 0) +#define AD3552R_MAX_REG_SIZE 3 +#define AD3552R_READ_BIT BIT(7) +#define AD3552R_ADDR_MASK GENMASK(6, 0) +#define AD3552R_MASK_DAC_12B 0xFFF0 +#define AD3552R_DEFAULT_CONFIG_B_VALUE 0x8 +#define AD3552R_SCRATCH_PAD_TEST_VAL1 0x34 +#define AD3552R_SCRATCH_PAD_TEST_VAL2 0xB2 +#define AD3552R_GAIN_SCALE 1000 +#define AD3552R_LDAC_PULSE_US 100 + +enum ad3552r_ch_vref_select { + /* Internal source with Vref I/O floating */ + AD3552R_INTERNAL_VREF_PIN_FLOATING, + /* Internal source with Vref I/O at 2.5V */ + AD3552R_INTERNAL_VREF_PIN_2P5V, + /* External source with Vref I/O as input */ + AD3552R_EXTERNAL_VREF_PIN_INPUT +}; + +enum ad3542r_id { + AD3542R_ID = 0x4009, + AD3552R_ID = 0x4008, +}; + +enum ad3552r_ch_output_range { + /* Range from 0 V to 2.5 V. Requires Rfb1x connection */ + AD3552R_CH_OUTPUT_RANGE_0__2P5V, + /* Range from 0 V to 5 V. Requires Rfb1x connection */ + AD3552R_CH_OUTPUT_RANGE_0__5V, + /* Range from 0 V to 10 V. Requires Rfb2x connection */ + AD3552R_CH_OUTPUT_RANGE_0__10V, + /* Range from -5 V to 5 V. Requires Rfb2x connection */ + AD3552R_CH_OUTPUT_RANGE_NEG_5__5V, + /* Range from -10 V to 10 V. Requires Rfb4x connection */ + AD3552R_CH_OUTPUT_RANGE_NEG_10__10V, +}; + +static const s32 ad3552r_ch_ranges[][2] = { + [AD3552R_CH_OUTPUT_RANGE_0__2P5V] = {0, 2500}, + [AD3552R_CH_OUTPUT_RANGE_0__5V] = {0, 5000}, + [AD3552R_CH_OUTPUT_RANGE_0__10V] = {0, 10000}, + [AD3552R_CH_OUTPUT_RANGE_NEG_5__5V] = {-5000, 5000}, + [AD3552R_CH_OUTPUT_RANGE_NEG_10__10V] = {-10000, 10000} +}; + +enum ad3542r_ch_output_range { + /* Range from 0 V to 2.5 V. Requires Rfb1x connection */ + AD3542R_CH_OUTPUT_RANGE_0__2P5V, + /* Range from 0 V to 3 V. Requires Rfb1x connection */ + AD3542R_CH_OUTPUT_RANGE_0__3V, + /* Range from 0 V to 5 V. Requires Rfb1x connection */ + AD3542R_CH_OUTPUT_RANGE_0__5V, + /* Range from 0 V to 10 V. Requires Rfb2x connection */ + AD3542R_CH_OUTPUT_RANGE_0__10V, + /* Range from -2.5 V to 7.5 V. Requires Rfb2x connection */ + AD3542R_CH_OUTPUT_RANGE_NEG_2P5__7P5V, + /* Range from -5 V to 5 V. Requires Rfb2x connection */ + AD3542R_CH_OUTPUT_RANGE_NEG_5__5V, +}; + +static const s32 ad3542r_ch_ranges[][2] = { + [AD3542R_CH_OUTPUT_RANGE_0__2P5V] = {0, 2500}, + [AD3542R_CH_OUTPUT_RANGE_0__3V] = {0, 3000}, + [AD3542R_CH_OUTPUT_RANGE_0__5V] = {0, 5000}, + [AD3542R_CH_OUTPUT_RANGE_0__10V] = {0, 10000}, + [AD3542R_CH_OUTPUT_RANGE_NEG_2P5__7P5V] = {-2500, 7500}, + [AD3542R_CH_OUTPUT_RANGE_NEG_5__5V] = {-5000, 5000} +}; + +enum ad3552r_ch_gain_scaling { + /* Gain scaling of 1 */ + AD3552R_CH_GAIN_SCALING_1, + /* Gain scaling of 0.5 */ + AD3552R_CH_GAIN_SCALING_0_5, + /* Gain scaling of 0.25 */ + AD3552R_CH_GAIN_SCALING_0_25, + /* Gain scaling of 0.125 */ + AD3552R_CH_GAIN_SCALING_0_125, +}; + +/* Gain * AD3552R_GAIN_SCALE */ +static const s32 gains_scaling_table[] = { + [AD3552R_CH_GAIN_SCALING_1] = 1000, + [AD3552R_CH_GAIN_SCALING_0_5] = 500, + [AD3552R_CH_GAIN_SCALING_0_25] = 250, + [AD3552R_CH_GAIN_SCALING_0_125] = 125 +}; + +enum ad3552r_dev_attributes { + /* - Direct register values */ + /* From 0-3 */ + AD3552R_SDO_DRIVE_STRENGTH, + /* + * 0 -> Internal Vref, vref_io pin floating (default) + * 1 -> Internal Vref, vref_io driven by internal vref + * 2 or 3 -> External Vref + */ + AD3552R_VREF_SELECT, + /* Read registers in ascending order if set. Else descending */ + AD3552R_ADDR_ASCENSION, +}; + +enum ad3552r_ch_attributes { + /* DAC powerdown */ + AD3552R_CH_DAC_POWERDOWN, + /* DAC amplifier powerdown */ + AD3552R_CH_AMPLIFIER_POWERDOWN, + /* Select the output range. Select from enum ad3552r_ch_output_range */ + AD3552R_CH_OUTPUT_RANGE_SEL, + /* + * Over-rider the range selector in order to manually set the output + * voltage range + */ + AD3552R_CH_RANGE_OVERRIDE, + /* Manually set the offset voltage */ + AD3552R_CH_GAIN_OFFSET, + /* Sets the polarity of the offset. */ + AD3552R_CH_GAIN_OFFSET_POLARITY, + /* PDAC gain scaling */ + AD3552R_CH_GAIN_SCALING_P, + /* NDAC gain scaling */ + AD3552R_CH_GAIN_SCALING_N, + /* Rfb value */ + AD3552R_CH_RFB, + /* Channel select. When set allow Input -> DAC and Mask -> DAC */ + AD3552R_CH_SELECT, +}; + +struct ad3552r_ch_data { + s32 scale_int; + s32 scale_dec; + s32 offset_int; + s32 offset_dec; + s16 gain_offset; + u16 rfb; + u8 n; + u8 p; + u8 range; + bool range_override; +}; + +struct ad3552r_desc { + /* 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_NUM_CH]; + struct iio_chan_spec channels[AD3552R_NUM_CH + 1]; + unsigned long enabled_ch; + unsigned int num_ch; + enum ad3542r_id chip_id; +}; + +static const u16 addr_mask_map[][2] = { + [AD3552R_ADDR_ASCENSION] = { + AD3552R_REG_ADDR_INTERFACE_CONFIG_A, + AD3552R_MASK_ADDR_ASCENSION + }, + [AD3552R_SDO_DRIVE_STRENGTH] = { + AD3552R_REG_ADDR_INTERFACE_CONFIG_D, + AD3552R_MASK_SDO_DRIVE_STRENGTH + }, + [AD3552R_VREF_SELECT] = { + AD3552R_REG_ADDR_SH_REFERENCE_CONFIG, + AD3552R_MASK_REFERENCE_VOLTAGE_SEL + }, +}; + +/* 0 -> reg addr, 1->ch0 mask, 2->ch1 mask */ +static const u16 addr_mask_map_ch[][3] = { + [AD3552R_CH_DAC_POWERDOWN] = { + AD3552R_REG_ADDR_POWERDOWN_CONFIG, + AD3552R_MASK_CH_DAC_POWERDOWN(0), + AD3552R_MASK_CH_DAC_POWERDOWN(1) + }, + [AD3552R_CH_AMPLIFIER_POWERDOWN] = { + AD3552R_REG_ADDR_POWERDOWN_CONFIG, + AD3552R_MASK_CH_AMPLIFIER_POWERDOWN(0), + AD3552R_MASK_CH_AMPLIFIER_POWERDOWN(1) + }, + [AD3552R_CH_OUTPUT_RANGE_SEL] = { + AD3552R_REG_ADDR_CH0_CH1_OUTPUT_RANGE, + AD3552R_MASK_CH_OUTPUT_RANGE_SEL(0), + AD3552R_MASK_CH_OUTPUT_RANGE_SEL(1) + }, + [AD3552R_CH_SELECT] = { + AD3552R_REG_ADDR_CH_SELECT_16B, + AD3552R_MASK_CH(0), + AD3552R_MASK_CH(1) + } +}; + +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; +} + +static u16 ad3552r_field_prep(u16 val, u16 mask) +{ + return (val << __ffs(mask)) & mask; +} + +/* 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 |= ad3552r_field_prep(val, mask); + + return ad3552r_write_reg(dac, addr, reg); +} + +static int ad3552r_set_ch_value(struct ad3552r_desc *dac, + enum ad3552r_ch_attributes attr, + u8 ch, + u16 val) +{ + /* Update register related to attributes in chip */ + return ad3552r_update_reg_field(dac, addr_mask_map_ch[attr][0], + addr_mask_map_ch[attr][ch + 1], val); +} + +#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: + err = ad3552r_set_ch_value(dac, AD3552R_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_NUM_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_NUM_CH * AD3552R_MAX_REG_SIZE]; + int err; + + memset(buff, 0, sizeof(buff)); + 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; + } + + return ad3552r_update_reg_field(dac, + addr_mask_map[AD3552R_ADDR_ASCENSION][0], + addr_mask_map[AD3552R_ADDR_ASCENSION][1], + val); +} + +static void ad3552r_get_custom_range(struct ad3552r_desc *dac, s32 i, s32 *v_min, + s32 *v_max) +{ + s64 vref, tmp, common, offset, gn, gp; + /* + * From datasheet formula (In Volts): + * Vmin = 2.5 + [(GainN + Offset / 1024) * 2.5 * Rfb * 1.03] + * Vmax = 2.5 - [(GainP + Offset / 1024) * 2.5 * Rfb * 1.03] + * Calculus are converted to milivolts + */ + vref = 2500; + /* 2.5 * 1.03 * 1000 (To mV) */ + common = 2575 * dac->ch_data[i].rfb; + offset = dac->ch_data[i].gain_offset; + + gn = gains_scaling_table[dac->ch_data[i].n]; + tmp = (1024 * gn + AD3552R_GAIN_SCALE * offset) * common; + tmp = div_s64(tmp, 1024 * AD3552R_GAIN_SCALE); + *v_max = vref + tmp; + + gp = gains_scaling_table[dac->ch_data[i].p]; + tmp = (1024 * gp - AD3552R_GAIN_SCALE * offset) * common; + tmp = div_s64(tmp, 1024 * AD3552R_GAIN_SCALE); + *v_min = vref - tmp; +} + +static void ad3552r_calc_gain_and_offset(struct ad3552r_desc *dac, s32 ch) +{ + s32 idx, v_max, v_min, span, rem; + s64 tmp; + + if (dac->ch_data[ch].range_override) { + ad3552r_get_custom_range(dac, ch, &v_min, &v_max); + } else { + /* Normal range */ + idx = dac->ch_data[ch].range; + if (dac->chip_id == AD3542R_ID) { + v_min = ad3542r_ch_ranges[idx][0]; + v_max = ad3542r_ch_ranges[idx][1]; + } else { + v_min = ad3552r_ch_ranges[idx][0]; + v_max = ad3552r_ch_ranges[idx][1]; + } + } + + /* + * From datasheet formula: + * Vout = Span * (D / 65536) + Vmin + * Converted to scale and offset: + * Scale = Span / 65536 + * Offset = 65536 * Vmin / Span + * + * Reminders are in micros in order to be printed as + * IIO_VAL_INT_PLUS_MICRO + */ + span = v_max - v_min; + dac->ch_data[ch].scale_int = div_s64_rem(span, 65536, &rem); + /* Do operations in microvolts */ + dac->ch_data[ch].scale_dec = DIV_ROUND_CLOSEST((s64)rem * 1000000, + 65536); + + dac->ch_data[ch].offset_int = div_s64_rem(v_min * 65536, span, &rem); + tmp = (s64)rem * 1000000; + dac->ch_data[ch].offset_dec = div_s64(tmp, span); +} + +static int ad3552r_find_range(u16 id, s32 *vals) +{ + int i, len; + const s32 (*ranges)[2]; + + if (id == AD3542R_ID) { + len = ARRAY_SIZE(ad3542r_ch_ranges); + ranges = ad3542r_ch_ranges; + } else { + len = ARRAY_SIZE(ad3552r_ch_ranges); + ranges = ad3552r_ch_ranges; + } + + for (i = 0; i < len; i++) + if (vals[0] == ranges[i][0] * 1000 && + vals[1] == ranges[i][1] * 1000) + return i; + + return -EINVAL; +} + +static int ad3552r_configure_custom_gain(struct ad3552r_desc *dac, + struct fwnode_handle *child, + u32 ch) +{ + struct device *dev = &dac->spi->dev; + struct fwnode_handle *gain_child; + u32 val; + int err; + u8 addr; + u16 reg = 0, offset; + + gain_child = fwnode_get_named_child_node(child, + "custom-output-range-config"); + if (!gain_child) { + dev_err(dev, + "mandatory custom-output-range-config property missing\n"); + return -EINVAL; + } + + dac->ch_data[ch].range_override = 1; + reg |= ad3552r_field_prep(1, AD3552R_MASK_CH_RANGE_OVERRIDE); + + err = fwnode_property_read_u32(gain_child, "adi,gain-scaling-p", &val); + if (err) { + dev_err(dev, "mandatory adi,gain-scaling-p property missing\n"); + goto put_child; + } + reg |= ad3552r_field_prep(val, AD3552R_MASK_CH_GAIN_SCALING_P); + dac->ch_data[ch].p = val; + + err = fwnode_property_read_u32(gain_child, "adi,gain-scaling-n", &val); + if (err) { + dev_err(dev, "mandatory adi,gain-scaling-n property missing\n"); + goto put_child; + } + reg |= ad3552r_field_prep(val, AD3552R_MASK_CH_GAIN_SCALING_N); + dac->ch_data[ch].n = val; + + err = fwnode_property_read_u32(gain_child, "adi,rfb-ohms", &val); + if (err) { + dev_err(dev, "mandatory adi,rfb-ohms property missing\n"); + goto put_child; + } + dac->ch_data[ch].rfb = val; + + err = fwnode_property_read_u32(gain_child, "adi,gain-offset", &val); + if (err) { + dev_err(dev, "mandatory adi,gain-offset property missing\n"); + goto put_child; + } + dac->ch_data[ch].gain_offset = val; + + offset = abs((s32)val); + reg |= ad3552r_field_prep((offset >> 8), AD3552R_MASK_CH_OFFSET_BIT_8); + + reg |= ad3552r_field_prep((s32)val < 0, AD3552R_MASK_CH_OFFSET_POLARITY); + addr = AD3552R_REG_ADDR_CH_GAIN(ch); + err = ad3552r_write_reg(dac, addr, + offset & AD3552R_MASK_CH_OFFSET_BITS_0_7); + if (err) { + dev_err(dev, "Error writing register\n"); + goto put_child; + } + + err = ad3552r_write_reg(dac, addr, reg); + if (err) { + dev_err(dev, "Error writing register\n"); + goto put_child; + } + +put_child: + fwnode_handle_put(gain_child); + + return err; +} + +static void ad3552r_reg_disable(void *reg) +{ + regulator_disable(reg); +} + +static int ad3552r_configure_device(struct ad3552r_desc *dac) +{ + struct device *dev = &dac->spi->dev; + struct fwnode_handle *child; + struct regulator *vref; + int err, cnt = 0, voltage, delta = 100000; + u32 vals[2], 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"); + + vref = devm_regulator_get_optional(dev, "vref"); + if (IS_ERR(vref)) { + if (PTR_ERR(vref) != -ENODEV) + return dev_err_probe(dev, PTR_ERR(vref), + "Error getting vref"); + + if (device_property_read_bool(dev, "adi,vref-out-en")) + val = AD3552R_INTERNAL_VREF_PIN_2P5V; + else + val = AD3552R_INTERNAL_VREF_PIN_FLOATING; + } else { + err = regulator_enable(vref); + if (err) { + dev_err(dev, "Failed to enable external vref supply\n"); + return err; + } + + err = devm_add_action_or_reset(dev, ad3552r_reg_disable, vref); + if (err) { + regulator_disable(vref); + return err; + } + + voltage = regulator_get_voltage(vref); + if (voltage > 2500000 + delta || voltage < 2500000 - delta) { + dev_warn(dev, "vref-supply must be 2.5V"); + return -EINVAL; + } + val = AD3552R_EXTERNAL_VREF_PIN_INPUT; + } + + err = ad3552r_update_reg_field(dac, + addr_mask_map[AD3552R_VREF_SELECT][0], + addr_mask_map[AD3552R_VREF_SELECT][1], + val); + if (err) + return err; + + err = device_property_read_u32(dev, "adi,sdo-drive-strength", &val); + if (!err) { + if (val > 3) { + dev_err(dev, "adi,sdo-drive-strength must be less than 4\n"); + return -EINVAL; + } + + err = ad3552r_update_reg_field(dac, + addr_mask_map[AD3552R_SDO_DRIVE_STRENGTH][0], + addr_mask_map[AD3552R_SDO_DRIVE_STRENGTH][1], + 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(dev, child) { + err = fwnode_property_read_u32(child, "reg", &ch); + if (err) { + dev_err(dev, "mandatory reg property missing\n"); + goto put_child; + } + if (ch >= AD3552R_NUM_CH) { + dev_err(dev, "reg must be less than %d\n", + AD3552R_NUM_CH); + err = -EINVAL; + goto put_child; + } + + if (fwnode_property_present(child, "adi,output-range-microvolt")) { + err = fwnode_property_read_u32_array(child, + "adi,output-range-microvolt", + vals, + 2); + if (err) { + dev_err(dev, + "adi,output-range-microvolt property could not be parsed\n"); + goto put_child; + } + + err = ad3552r_find_range(dac->chip_id, vals); + if (err < 0) { + dev_err(dev, + "Invalid adi,output-range-microvolt value\n"); + goto put_child; + } + val = err; + err = ad3552r_set_ch_value(dac, + AD3552R_CH_OUTPUT_RANGE_SEL, + ch, val); + if (err) + goto put_child; + + dac->ch_data[ch].range = val; + } else if (dac->chip_id == AD3542R_ID) { + dev_err(dev, + "adi,output-range-microvolt is required for ad3542r\n"); + err = -EINVAL; + goto put_child; + } else { + err = ad3552r_configure_custom_gain(dac, child, ch); + if (err) + goto put_child; + } + + ad3552r_calc_gain_and_offset(dac, ch); + dac->enabled_ch |= BIT(ch); + + err = ad3552r_set_ch_value(dac, AD3552R_CH_SELECT, ch, 1); + if (err < 0) + goto put_child; + + dac->channels[cnt] = AD3552R_CH_DAC(ch); + ++cnt; + + } + + /* Disable unused channels */ + for_each_clear_bit(ch, &dac->enabled_ch, AD3552R_NUM_CH) { + err = ad3552r_set_ch_value(dac, AD3552R_CH_AMPLIFIER_POWERDOWN, + ch, 1); + if (err) + return err; + } + + dac->num_ch = cnt; + + return 0; +put_child: + fwnode_handle_put(child); + + return err; +} + +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->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) +{ + const struct spi_device_id *id = spi_get_device_id(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->chip_id = id->driver_data; + + mutex_init(&dac->lock); + + err = ad3552r_init(dac); + if (err) + return err; + + /* Config triggered buffer device */ + if (dac->chip_id == AD3552R_ID) + indio_dev->name = "ad3552r"; + else + indio_dev->name = "ad3542r"; + 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[] = { + { "ad3542r", AD3542R_ID }, + { "ad3552r", AD3552R_ID }, + { } +}; +MODULE_DEVICE_TABLE(spi, ad3552r_id); + +static const struct of_device_id ad3552r_of_match[] = { + { .compatible = "adi,ad3542r"}, + { .compatible = "adi,ad3552r"}, + { } +}; +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"); |