diff options
Diffstat (limited to 'drivers/iio/adc/ad4130.c')
| -rw-r--r-- | drivers/iio/adc/ad4130.c | 2110 |
1 files changed, 2110 insertions, 0 deletions
diff --git a/drivers/iio/adc/ad4130.c b/drivers/iio/adc/ad4130.c new file mode 100644 index 0000000000..5a5dd5e87f --- /dev/null +++ b/drivers/iio/adc/ad4130.c @@ -0,0 +1,2110 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2022 Analog Devices, Inc. + * Author: Cosmin Tanislav <cosmin.tanislav@analog.com> + */ + +#include <linux/bitfield.h> +#include <linux/bitops.h> +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/gpio/driver.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/property.h> +#include <linux/regmap.h> +#include <linux/regulator/consumer.h> +#include <linux/spi/spi.h> +#include <linux/units.h> + +#include <asm/div64.h> +#include <asm/unaligned.h> + +#include <linux/iio/buffer.h> +#include <linux/iio/iio.h> +#include <linux/iio/kfifo_buf.h> +#include <linux/iio/sysfs.h> + +#define AD4130_NAME "ad4130" + +#define AD4130_COMMS_READ_MASK BIT(6) + +#define AD4130_STATUS_REG 0x00 + +#define AD4130_ADC_CONTROL_REG 0x01 +#define AD4130_ADC_CONTROL_BIPOLAR_MASK BIT(14) +#define AD4130_ADC_CONTROL_INT_REF_VAL_MASK BIT(13) +#define AD4130_INT_REF_2_5V 2500000 +#define AD4130_INT_REF_1_25V 1250000 +#define AD4130_ADC_CONTROL_CSB_EN_MASK BIT(9) +#define AD4130_ADC_CONTROL_INT_REF_EN_MASK BIT(8) +#define AD4130_ADC_CONTROL_MODE_MASK GENMASK(5, 2) +#define AD4130_ADC_CONTROL_MCLK_SEL_MASK GENMASK(1, 0) +#define AD4130_MCLK_FREQ_76_8KHZ 76800 +#define AD4130_MCLK_FREQ_153_6KHZ 153600 + +#define AD4130_DATA_REG 0x02 + +#define AD4130_IO_CONTROL_REG 0x03 +#define AD4130_IO_CONTROL_INT_PIN_SEL_MASK GENMASK(9, 8) +#define AD4130_IO_CONTROL_GPIO_DATA_MASK GENMASK(7, 4) +#define AD4130_IO_CONTROL_GPIO_CTRL_MASK GENMASK(3, 0) + +#define AD4130_VBIAS_REG 0x04 + +#define AD4130_ID_REG 0x05 + +#define AD4130_ERROR_REG 0x06 + +#define AD4130_ERROR_EN_REG 0x07 + +#define AD4130_MCLK_COUNT_REG 0x08 + +#define AD4130_CHANNEL_X_REG(x) (0x09 + (x)) +#define AD4130_CHANNEL_EN_MASK BIT(23) +#define AD4130_CHANNEL_SETUP_MASK GENMASK(22, 20) +#define AD4130_CHANNEL_AINP_MASK GENMASK(17, 13) +#define AD4130_CHANNEL_AINM_MASK GENMASK(12, 8) +#define AD4130_CHANNEL_IOUT1_MASK GENMASK(7, 4) +#define AD4130_CHANNEL_IOUT2_MASK GENMASK(3, 0) + +#define AD4130_CONFIG_X_REG(x) (0x19 + (x)) +#define AD4130_CONFIG_IOUT1_VAL_MASK GENMASK(15, 13) +#define AD4130_CONFIG_IOUT2_VAL_MASK GENMASK(12, 10) +#define AD4130_CONFIG_BURNOUT_MASK GENMASK(9, 8) +#define AD4130_CONFIG_REF_BUFP_MASK BIT(7) +#define AD4130_CONFIG_REF_BUFM_MASK BIT(6) +#define AD4130_CONFIG_REF_SEL_MASK GENMASK(5, 4) +#define AD4130_CONFIG_PGA_MASK GENMASK(3, 1) + +#define AD4130_FILTER_X_REG(x) (0x21 + (x)) +#define AD4130_FILTER_MODE_MASK GENMASK(15, 12) +#define AD4130_FILTER_SELECT_MASK GENMASK(10, 0) +#define AD4130_FILTER_SELECT_MIN 1 + +#define AD4130_OFFSET_X_REG(x) (0x29 + (x)) + +#define AD4130_GAIN_X_REG(x) (0x31 + (x)) + +#define AD4130_MISC_REG 0x39 + +#define AD4130_FIFO_CONTROL_REG 0x3a +#define AD4130_FIFO_CONTROL_HEADER_MASK BIT(18) +#define AD4130_FIFO_CONTROL_MODE_MASK GENMASK(17, 16) +#define AD4130_FIFO_CONTROL_WM_INT_EN_MASK BIT(9) +#define AD4130_FIFO_CONTROL_WM_MASK GENMASK(7, 0) +#define AD4130_WATERMARK_256 0 + +#define AD4130_FIFO_STATUS_REG 0x3b + +#define AD4130_FIFO_THRESHOLD_REG 0x3c + +#define AD4130_FIFO_DATA_REG 0x3d +#define AD4130_FIFO_SIZE 256 +#define AD4130_FIFO_MAX_SAMPLE_SIZE 3 + +#define AD4130_MAX_ANALOG_PINS 16 +#define AD4130_MAX_CHANNELS 16 +#define AD4130_MAX_DIFF_INPUTS 30 +#define AD4130_MAX_GPIOS 4 +#define AD4130_MAX_ODR 2400 +#define AD4130_MAX_PGA 8 +#define AD4130_MAX_SETUPS 8 + +#define AD4130_AIN2_P1 0x2 +#define AD4130_AIN3_P2 0x3 + +#define AD4130_RESET_BUF_SIZE 8 +#define AD4130_RESET_SLEEP_US (160 * MICRO / AD4130_MCLK_FREQ_76_8KHZ) + +#define AD4130_INVALID_SLOT -1 + +static const unsigned int ad4130_reg_size[] = { + [AD4130_STATUS_REG] = 1, + [AD4130_ADC_CONTROL_REG] = 2, + [AD4130_DATA_REG] = 3, + [AD4130_IO_CONTROL_REG] = 2, + [AD4130_VBIAS_REG] = 2, + [AD4130_ID_REG] = 1, + [AD4130_ERROR_REG] = 2, + [AD4130_ERROR_EN_REG] = 2, + [AD4130_MCLK_COUNT_REG] = 1, + [AD4130_CHANNEL_X_REG(0) ... AD4130_CHANNEL_X_REG(AD4130_MAX_CHANNELS - 1)] = 3, + [AD4130_CONFIG_X_REG(0) ... AD4130_CONFIG_X_REG(AD4130_MAX_SETUPS - 1)] = 2, + [AD4130_FILTER_X_REG(0) ... AD4130_FILTER_X_REG(AD4130_MAX_SETUPS - 1)] = 3, + [AD4130_OFFSET_X_REG(0) ... AD4130_OFFSET_X_REG(AD4130_MAX_SETUPS - 1)] = 3, + [AD4130_GAIN_X_REG(0) ... AD4130_GAIN_X_REG(AD4130_MAX_SETUPS - 1)] = 3, + [AD4130_MISC_REG] = 2, + [AD4130_FIFO_CONTROL_REG] = 3, + [AD4130_FIFO_STATUS_REG] = 1, + [AD4130_FIFO_THRESHOLD_REG] = 3, + [AD4130_FIFO_DATA_REG] = 3, +}; + +enum ad4130_int_ref_val { + AD4130_INT_REF_VAL_2_5V, + AD4130_INT_REF_VAL_1_25V, +}; + +enum ad4130_mclk_sel { + AD4130_MCLK_76_8KHZ, + AD4130_MCLK_76_8KHZ_OUT, + AD4130_MCLK_76_8KHZ_EXT, + AD4130_MCLK_153_6KHZ_EXT, +}; + +enum ad4130_int_pin_sel { + AD4130_INT_PIN_INT, + AD4130_INT_PIN_CLK, + AD4130_INT_PIN_P2, + AD4130_INT_PIN_DOUT, +}; + +enum ad4130_iout { + AD4130_IOUT_OFF, + AD4130_IOUT_10000NA, + AD4130_IOUT_20000NA, + AD4130_IOUT_50000NA, + AD4130_IOUT_100000NA, + AD4130_IOUT_150000NA, + AD4130_IOUT_200000NA, + AD4130_IOUT_100NA, + AD4130_IOUT_MAX +}; + +enum ad4130_burnout { + AD4130_BURNOUT_OFF, + AD4130_BURNOUT_500NA, + AD4130_BURNOUT_2000NA, + AD4130_BURNOUT_4000NA, + AD4130_BURNOUT_MAX +}; + +enum ad4130_ref_sel { + AD4130_REF_REFIN1, + AD4130_REF_REFIN2, + AD4130_REF_REFOUT_AVSS, + AD4130_REF_AVDD_AVSS, + AD4130_REF_SEL_MAX +}; + +enum ad4130_fifo_mode { + AD4130_FIFO_MODE_DISABLED = 0b00, + AD4130_FIFO_MODE_WM = 0b01, +}; + +enum ad4130_mode { + AD4130_MODE_CONTINUOUS = 0b0000, + AD4130_MODE_IDLE = 0b0100, +}; + +enum ad4130_filter_mode { + AD4130_FILTER_SINC4, + AD4130_FILTER_SINC4_SINC1, + AD4130_FILTER_SINC3, + AD4130_FILTER_SINC3_REJ60, + AD4130_FILTER_SINC3_SINC1, + AD4130_FILTER_SINC3_PF1, + AD4130_FILTER_SINC3_PF2, + AD4130_FILTER_SINC3_PF3, + AD4130_FILTER_SINC3_PF4, +}; + +enum ad4130_pin_function { + AD4130_PIN_FN_NONE, + AD4130_PIN_FN_SPECIAL = BIT(0), + AD4130_PIN_FN_DIFF = BIT(1), + AD4130_PIN_FN_EXCITATION = BIT(2), + AD4130_PIN_FN_VBIAS = BIT(3), +}; + +struct ad4130_setup_info { + unsigned int iout0_val; + unsigned int iout1_val; + unsigned int burnout; + unsigned int pga; + unsigned int fs; + u32 ref_sel; + enum ad4130_filter_mode filter_mode; + bool ref_bufp; + bool ref_bufm; +}; + +struct ad4130_slot_info { + struct ad4130_setup_info setup; + unsigned int enabled_channels; + unsigned int channels; +}; + +struct ad4130_chan_info { + struct ad4130_setup_info setup; + u32 iout0; + u32 iout1; + int slot; + bool enabled; + bool initialized; +}; + +struct ad4130_filter_config { + enum ad4130_filter_mode filter_mode; + unsigned int odr_div; + unsigned int fs_max; + enum iio_available_type samp_freq_avail_type; + int samp_freq_avail_len; + int samp_freq_avail[3][2]; +}; + +struct ad4130_state { + struct regmap *regmap; + struct spi_device *spi; + struct clk *mclk; + struct regulator_bulk_data regulators[4]; + u32 irq_trigger; + u32 inv_irq_trigger; + + /* + * Synchronize access to members the of driver state, and ensure + * atomicity of consecutive regmap operations. + */ + struct mutex lock; + struct completion completion; + + struct iio_chan_spec chans[AD4130_MAX_CHANNELS]; + struct ad4130_chan_info chans_info[AD4130_MAX_CHANNELS]; + struct ad4130_slot_info slots_info[AD4130_MAX_SETUPS]; + enum ad4130_pin_function pins_fn[AD4130_MAX_ANALOG_PINS]; + u32 vbias_pins[AD4130_MAX_ANALOG_PINS]; + u32 num_vbias_pins; + int scale_tbls[AD4130_REF_SEL_MAX][AD4130_MAX_PGA][2]; + struct gpio_chip gc; + struct clk_hw int_clk_hw; + + u32 int_pin_sel; + u32 int_ref_uv; + u32 mclk_sel; + bool int_ref_en; + bool bipolar; + + unsigned int num_enabled_channels; + unsigned int effective_watermark; + unsigned int watermark; + + struct spi_message fifo_msg; + struct spi_transfer fifo_xfer[2]; + + /* + * DMA (thus cache coherency maintenance) requires any transfer + * buffers to live in their own cache lines. As the use of these + * buffers is synchronous, all of the buffers used for DMA in this + * driver may share a cache line. + */ + u8 reset_buf[AD4130_RESET_BUF_SIZE] __aligned(IIO_DMA_MINALIGN); + u8 reg_write_tx_buf[4]; + u8 reg_read_tx_buf[1]; + u8 reg_read_rx_buf[3]; + u8 fifo_tx_buf[2]; + u8 fifo_rx_buf[AD4130_FIFO_SIZE * + AD4130_FIFO_MAX_SAMPLE_SIZE]; +}; + +static const char * const ad4130_int_pin_names[] = { + [AD4130_INT_PIN_INT] = "int", + [AD4130_INT_PIN_CLK] = "clk", + [AD4130_INT_PIN_P2] = "p2", + [AD4130_INT_PIN_DOUT] = "dout", +}; + +static const unsigned int ad4130_iout_current_na_tbl[AD4130_IOUT_MAX] = { + [AD4130_IOUT_OFF] = 0, + [AD4130_IOUT_100NA] = 100, + [AD4130_IOUT_10000NA] = 10000, + [AD4130_IOUT_20000NA] = 20000, + [AD4130_IOUT_50000NA] = 50000, + [AD4130_IOUT_100000NA] = 100000, + [AD4130_IOUT_150000NA] = 150000, + [AD4130_IOUT_200000NA] = 200000, +}; + +static const unsigned int ad4130_burnout_current_na_tbl[AD4130_BURNOUT_MAX] = { + [AD4130_BURNOUT_OFF] = 0, + [AD4130_BURNOUT_500NA] = 500, + [AD4130_BURNOUT_2000NA] = 2000, + [AD4130_BURNOUT_4000NA] = 4000, +}; + +#define AD4130_VARIABLE_ODR_CONFIG(_filter_mode, _odr_div, _fs_max) \ +{ \ + .filter_mode = (_filter_mode), \ + .odr_div = (_odr_div), \ + .fs_max = (_fs_max), \ + .samp_freq_avail_type = IIO_AVAIL_RANGE, \ + .samp_freq_avail = { \ + { AD4130_MAX_ODR, (_odr_div) * (_fs_max) }, \ + { AD4130_MAX_ODR, (_odr_div) * (_fs_max) }, \ + { AD4130_MAX_ODR, (_odr_div) }, \ + }, \ +} + +#define AD4130_FIXED_ODR_CONFIG(_filter_mode, _odr_div) \ +{ \ + .filter_mode = (_filter_mode), \ + .odr_div = (_odr_div), \ + .fs_max = AD4130_FILTER_SELECT_MIN, \ + .samp_freq_avail_type = IIO_AVAIL_LIST, \ + .samp_freq_avail_len = 1, \ + .samp_freq_avail = { \ + { AD4130_MAX_ODR, (_odr_div) }, \ + }, \ +} + +static const struct ad4130_filter_config ad4130_filter_configs[] = { + AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC4, 1, 10), + AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC4_SINC1, 11, 10), + AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC3, 1, 2047), + AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC3_REJ60, 1, 2047), + AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC3_SINC1, 10, 2047), + AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF1, 92), + AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF2, 100), + AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF3, 124), + AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF4, 148), +}; + +static const char * const ad4130_filter_modes_str[] = { + [AD4130_FILTER_SINC4] = "sinc4", + [AD4130_FILTER_SINC4_SINC1] = "sinc4+sinc1", + [AD4130_FILTER_SINC3] = "sinc3", + [AD4130_FILTER_SINC3_REJ60] = "sinc3+rej60", + [AD4130_FILTER_SINC3_SINC1] = "sinc3+sinc1", + [AD4130_FILTER_SINC3_PF1] = "sinc3+pf1", + [AD4130_FILTER_SINC3_PF2] = "sinc3+pf2", + [AD4130_FILTER_SINC3_PF3] = "sinc3+pf3", + [AD4130_FILTER_SINC3_PF4] = "sinc3+pf4", +}; + +static int ad4130_get_reg_size(struct ad4130_state *st, unsigned int reg, + unsigned int *size) +{ + if (reg >= ARRAY_SIZE(ad4130_reg_size)) + return -EINVAL; + + *size = ad4130_reg_size[reg]; + + return 0; +} + +static unsigned int ad4130_data_reg_size(struct ad4130_state *st) +{ + unsigned int data_reg_size; + int ret; + + ret = ad4130_get_reg_size(st, AD4130_DATA_REG, &data_reg_size); + if (ret) + return 0; + + return data_reg_size; +} + +static unsigned int ad4130_resolution(struct ad4130_state *st) +{ + return ad4130_data_reg_size(st) * BITS_PER_BYTE; +} + +static int ad4130_reg_write(void *context, unsigned int reg, unsigned int val) +{ + struct ad4130_state *st = context; + unsigned int size; + int ret; + + ret = ad4130_get_reg_size(st, reg, &size); + if (ret) + return ret; + + st->reg_write_tx_buf[0] = reg; + + switch (size) { + case 3: + put_unaligned_be24(val, &st->reg_write_tx_buf[1]); + break; + case 2: + put_unaligned_be16(val, &st->reg_write_tx_buf[1]); + break; + case 1: + st->reg_write_tx_buf[1] = val; + break; + default: + return -EINVAL; + } + + return spi_write(st->spi, st->reg_write_tx_buf, size + 1); +} + +static int ad4130_reg_read(void *context, unsigned int reg, unsigned int *val) +{ + struct ad4130_state *st = context; + struct spi_transfer t[] = { + { + .tx_buf = st->reg_read_tx_buf, + .len = sizeof(st->reg_read_tx_buf), + }, + { + .rx_buf = st->reg_read_rx_buf, + }, + }; + unsigned int size; + int ret; + + ret = ad4130_get_reg_size(st, reg, &size); + if (ret) + return ret; + + st->reg_read_tx_buf[0] = AD4130_COMMS_READ_MASK | reg; + t[1].len = size; + + ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t)); + if (ret) + return ret; + + switch (size) { + case 3: + *val = get_unaligned_be24(st->reg_read_rx_buf); + break; + case 2: + *val = get_unaligned_be16(st->reg_read_rx_buf); + break; + case 1: + *val = st->reg_read_rx_buf[0]; + break; + default: + return -EINVAL; + } + + return 0; +} + +static const struct regmap_config ad4130_regmap_config = { + .reg_read = ad4130_reg_read, + .reg_write = ad4130_reg_write, +}; + +static int ad4130_gpio_init_valid_mask(struct gpio_chip *gc, + unsigned long *valid_mask, + unsigned int ngpios) +{ + struct ad4130_state *st = gpiochip_get_data(gc); + unsigned int i; + + /* + * Output-only GPIO functionality is available on pins AIN2 through + * AIN5. If these pins are used for anything else, do not expose them. + */ + for (i = 0; i < ngpios; i++) { + unsigned int pin = i + AD4130_AIN2_P1; + bool valid = st->pins_fn[pin] == AD4130_PIN_FN_NONE; + + __assign_bit(i, valid_mask, valid); + } + + return 0; +} + +static int ad4130_gpio_get_direction(struct gpio_chip *gc, unsigned int offset) +{ + return GPIO_LINE_DIRECTION_OUT; +} + +static void ad4130_gpio_set(struct gpio_chip *gc, unsigned int offset, + int value) +{ + struct ad4130_state *st = gpiochip_get_data(gc); + unsigned int mask = FIELD_PREP(AD4130_IO_CONTROL_GPIO_DATA_MASK, + BIT(offset)); + + regmap_update_bits(st->regmap, AD4130_IO_CONTROL_REG, mask, + value ? mask : 0); +} + +static int ad4130_set_mode(struct ad4130_state *st, enum ad4130_mode mode) +{ + return regmap_update_bits(st->regmap, AD4130_ADC_CONTROL_REG, + AD4130_ADC_CONTROL_MODE_MASK, + FIELD_PREP(AD4130_ADC_CONTROL_MODE_MASK, mode)); +} + +static int ad4130_set_watermark_interrupt_en(struct ad4130_state *st, bool en) +{ + return regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG, + AD4130_FIFO_CONTROL_WM_INT_EN_MASK, + FIELD_PREP(AD4130_FIFO_CONTROL_WM_INT_EN_MASK, en)); +} + +static unsigned int ad4130_watermark_reg_val(unsigned int val) +{ + if (val == AD4130_FIFO_SIZE) + val = AD4130_WATERMARK_256; + + return val; +} + +static int ad4130_set_fifo_mode(struct ad4130_state *st, + enum ad4130_fifo_mode mode) +{ + return regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG, + AD4130_FIFO_CONTROL_MODE_MASK, + FIELD_PREP(AD4130_FIFO_CONTROL_MODE_MASK, mode)); +} + +static void ad4130_push_fifo_data(struct iio_dev *indio_dev) +{ + struct ad4130_state *st = iio_priv(indio_dev); + unsigned int data_reg_size = ad4130_data_reg_size(st); + unsigned int transfer_len = st->effective_watermark * data_reg_size; + unsigned int set_size = st->num_enabled_channels * data_reg_size; + unsigned int i; + int ret; + + st->fifo_tx_buf[1] = ad4130_watermark_reg_val(st->effective_watermark); + st->fifo_xfer[1].len = transfer_len; + + ret = spi_sync(st->spi, &st->fifo_msg); + if (ret) + return; + + for (i = 0; i < transfer_len; i += set_size) + iio_push_to_buffers(indio_dev, &st->fifo_rx_buf[i]); +} + +static irqreturn_t ad4130_irq_handler(int irq, void *private) +{ + struct iio_dev *indio_dev = private; + struct ad4130_state *st = iio_priv(indio_dev); + + if (iio_buffer_enabled(indio_dev)) + ad4130_push_fifo_data(indio_dev); + else + complete(&st->completion); + + return IRQ_HANDLED; +} + +static int ad4130_find_slot(struct ad4130_state *st, + struct ad4130_setup_info *target_setup_info, + unsigned int *slot, bool *overwrite) +{ + unsigned int i; + + *slot = AD4130_INVALID_SLOT; + *overwrite = false; + + for (i = 0; i < AD4130_MAX_SETUPS; i++) { + struct ad4130_slot_info *slot_info = &st->slots_info[i]; + + /* Immediately accept a matching setup info. */ + if (!memcmp(target_setup_info, &slot_info->setup, + sizeof(*target_setup_info))) { + *slot = i; + return 0; + } + + /* Ignore all setups which are used by enabled channels. */ + if (slot_info->enabled_channels) + continue; + + /* Find the least used slot. */ + if (*slot == AD4130_INVALID_SLOT || + slot_info->channels < st->slots_info[*slot].channels) + *slot = i; + } + + if (*slot == AD4130_INVALID_SLOT) + return -EINVAL; + + *overwrite = true; + + return 0; +} + +static void ad4130_unlink_channel(struct ad4130_state *st, unsigned int channel) +{ + struct ad4130_chan_info *chan_info = &st->chans_info[channel]; + struct ad4130_slot_info *slot_info = &st->slots_info[chan_info->slot]; + + chan_info->slot = AD4130_INVALID_SLOT; + slot_info->channels--; +} + +static int ad4130_unlink_slot(struct ad4130_state *st, unsigned int slot) +{ + unsigned int i; + + for (i = 0; i < AD4130_MAX_CHANNELS; i++) { + struct ad4130_chan_info *chan_info = &st->chans_info[i]; + + if (!chan_info->initialized || chan_info->slot != slot) + continue; + + ad4130_unlink_channel(st, i); + } + + return 0; +} + +static int ad4130_link_channel_slot(struct ad4130_state *st, + unsigned int channel, unsigned int slot) +{ + struct ad4130_slot_info *slot_info = &st->slots_info[slot]; + struct ad4130_chan_info *chan_info = &st->chans_info[channel]; + int ret; + + ret = regmap_update_bits(st->regmap, AD4130_CHANNEL_X_REG(channel), + AD4130_CHANNEL_SETUP_MASK, + FIELD_PREP(AD4130_CHANNEL_SETUP_MASK, slot)); + if (ret) + return ret; + + chan_info->slot = slot; + slot_info->channels++; + + return 0; +} + +static int ad4130_write_slot_setup(struct ad4130_state *st, + unsigned int slot, + struct ad4130_setup_info *setup_info) +{ + unsigned int val; + int ret; + + val = FIELD_PREP(AD4130_CONFIG_IOUT1_VAL_MASK, setup_info->iout0_val) | + FIELD_PREP(AD4130_CONFIG_IOUT1_VAL_MASK, setup_info->iout1_val) | + FIELD_PREP(AD4130_CONFIG_BURNOUT_MASK, setup_info->burnout) | + FIELD_PREP(AD4130_CONFIG_REF_BUFP_MASK, setup_info->ref_bufp) | + FIELD_PREP(AD4130_CONFIG_REF_BUFM_MASK, setup_info->ref_bufm) | + FIELD_PREP(AD4130_CONFIG_REF_SEL_MASK, setup_info->ref_sel) | + FIELD_PREP(AD4130_CONFIG_PGA_MASK, setup_info->pga); + + ret = regmap_write(st->regmap, AD4130_CONFIG_X_REG(slot), val); + if (ret) + return ret; + + val = FIELD_PREP(AD4130_FILTER_MODE_MASK, setup_info->filter_mode) | + FIELD_PREP(AD4130_FILTER_SELECT_MASK, setup_info->fs); + + ret = regmap_write(st->regmap, AD4130_FILTER_X_REG(slot), val); + if (ret) + return ret; + + memcpy(&st->slots_info[slot].setup, setup_info, sizeof(*setup_info)); + + return 0; +} + +static int ad4130_write_channel_setup(struct ad4130_state *st, + unsigned int channel, bool on_enable) +{ + struct ad4130_chan_info *chan_info = &st->chans_info[channel]; + struct ad4130_setup_info *setup_info = &chan_info->setup; + bool overwrite; + int slot; + int ret; + + /* + * The following cases need to be handled. + * + * 1. Enabled and linked channel with setup changes: + * - Find a slot. If not possible, return error. + * - Unlink channel from current slot. + * - If the slot has channels linked to it, unlink all channels, and + * write the new setup to it. + * - Link channel to new slot. + * + * 2. Soon to be enabled and unlinked channel: + * - Find a slot. If not possible, return error. + * - If the slot has channels linked to it, unlink all channels, and + * write the new setup to it. + * - Link channel to the slot. + * + * 3. Disabled and linked channel with setup changes: + * - Unlink channel from current slot. + * + * 4. Soon to be enabled and linked channel: + * 5. Disabled and unlinked channel with setup changes: + * - Do nothing. + */ + + /* Case 4 */ + if (on_enable && chan_info->slot != AD4130_INVALID_SLOT) + return 0; + + if (!on_enable && !chan_info->enabled) { + if (chan_info->slot != AD4130_INVALID_SLOT) + /* Case 3 */ + ad4130_unlink_channel(st, channel); + + /* Cases 3 & 5 */ + return 0; + } + + /* Cases 1 & 2 */ + ret = ad4130_find_slot(st, setup_info, &slot, &overwrite); + if (ret) + return ret; + + if (chan_info->slot != AD4130_INVALID_SLOT) + /* Case 1 */ + ad4130_unlink_channel(st, channel); + + if (overwrite) { + ret = ad4130_unlink_slot(st, slot); + if (ret) + return ret; + + ret = ad4130_write_slot_setup(st, slot, setup_info); + if (ret) + return ret; + } + + return ad4130_link_channel_slot(st, channel, slot); +} + +static int ad4130_set_channel_enable(struct ad4130_state *st, + unsigned int channel, bool status) +{ + struct ad4130_chan_info *chan_info = &st->chans_info[channel]; + struct ad4130_slot_info *slot_info; + int ret; + + if (chan_info->enabled == status) + return 0; + + if (status) { + ret = ad4130_write_channel_setup(st, channel, true); + if (ret) + return ret; + } + + slot_info = &st->slots_info[chan_info->slot]; + + ret = regmap_update_bits(st->regmap, AD4130_CHANNEL_X_REG(channel), + AD4130_CHANNEL_EN_MASK, + FIELD_PREP(AD4130_CHANNEL_EN_MASK, status)); + if (ret) + return ret; + + slot_info->enabled_channels += status ? 1 : -1; + chan_info->enabled = status; + + return 0; +} + +/* + * Table 58. FILTER_MODE_n bits and Filter Types of the datasheet describes + * the relation between filter mode, ODR and FS. + * + * Notice that the max ODR of each filter mode is not necessarily the + * absolute max ODR supported by the chip. + * + * The ODR divider is not explicitly specified, but it can be deduced based + * on the ODR range of each filter mode. + * + * For example, for Sinc4+Sinc1, max ODR is 218.18. That means that the + * absolute max ODR is divided by 11 to achieve the max ODR of this filter + * mode. + * + * The formulas for converting between ODR and FS for a specific filter + * mode can be deduced from the same table. + * + * Notice that FS = 1 actually means max ODR, and that ODR decreases by + * (maximum ODR / maximum FS) for each increment of FS. + * + * odr = MAX_ODR / odr_div * (1 - (fs - 1) / fs_max) <=> + * odr = MAX_ODR * (1 - (fs - 1) / fs_max) / odr_div <=> + * odr = MAX_ODR * (1 - (fs - 1) / fs_max) / odr_div <=> + * odr = MAX_ODR * (fs_max - fs + 1) / (fs_max * odr_div) + * (used in ad4130_fs_to_freq) + * + * For the opposite formula, FS can be extracted from the last one. + * + * MAX_ODR * (fs_max - fs + 1) = fs_max * odr_div * odr <=> + * fs_max - fs + 1 = fs_max * odr_div * odr / MAX_ODR <=> + * fs = 1 + fs_max - fs_max * odr_div * odr / MAX_ODR + * (used in ad4130_fs_to_freq) + */ + +static void ad4130_freq_to_fs(enum ad4130_filter_mode filter_mode, + int val, int val2, unsigned int *fs) +{ + const struct ad4130_filter_config *filter_config = + &ad4130_filter_configs[filter_mode]; + u64 dividend, divisor; + int temp; + + dividend = filter_config->fs_max * filter_config->odr_div * + ((u64)val * NANO + val2); + divisor = (u64)AD4130_MAX_ODR * NANO; + + temp = AD4130_FILTER_SELECT_MIN + filter_config->fs_max - + DIV64_U64_ROUND_CLOSEST(dividend, divisor); + + if (temp < AD4130_FILTER_SELECT_MIN) + temp = AD4130_FILTER_SELECT_MIN; + else if (temp > filter_config->fs_max) + temp = filter_config->fs_max; + + *fs = temp; +} + +static void ad4130_fs_to_freq(enum ad4130_filter_mode filter_mode, + unsigned int fs, int *val, int *val2) +{ + const struct ad4130_filter_config *filter_config = + &ad4130_filter_configs[filter_mode]; + unsigned int dividend, divisor; + u64 temp; + + dividend = (filter_config->fs_max - fs + AD4130_FILTER_SELECT_MIN) * + AD4130_MAX_ODR; + divisor = filter_config->fs_max * filter_config->odr_div; + + temp = div_u64((u64)dividend * NANO, divisor); + *val = div_u64_rem(temp, NANO, val2); +} + +static int ad4130_set_filter_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + unsigned int val) +{ + struct ad4130_state *st = iio_priv(indio_dev); + unsigned int channel = chan->scan_index; + struct ad4130_chan_info *chan_info = &st->chans_info[channel]; + struct ad4130_setup_info *setup_info = &chan_info->setup; + enum ad4130_filter_mode old_filter_mode; + int freq_val, freq_val2; + unsigned int old_fs; + int ret = 0; + + mutex_lock(&st->lock); + if (setup_info->filter_mode == val) + goto out; + + old_fs = setup_info->fs; + old_filter_mode = setup_info->filter_mode; + + /* + * When switching between filter modes, try to match the ODR as + * close as possible. To do this, convert the current FS into ODR + * using the old filter mode, then convert it back into FS using + * the new filter mode. + */ + ad4130_fs_to_freq(setup_info->filter_mode, setup_info->fs, + &freq_val, &freq_val2); + + ad4130_freq_to_fs(val, freq_val, freq_val2, &setup_info->fs); + + setup_info->filter_mode = val; + + ret = ad4130_write_channel_setup(st, channel, false); + if (ret) { + setup_info->fs = old_fs; + setup_info->filter_mode = old_filter_mode; + } + + out: + mutex_unlock(&st->lock); + + return ret; +} + +static int ad4130_get_filter_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan) +{ + struct ad4130_state *st = iio_priv(indio_dev); + unsigned int channel = chan->scan_index; + struct ad4130_setup_info *setup_info = &st->chans_info[channel].setup; + enum ad4130_filter_mode filter_mode; + + mutex_lock(&st->lock); + filter_mode = setup_info->filter_mode; + mutex_unlock(&st->lock); + + return filter_mode; +} + +static const struct iio_enum ad4130_filter_mode_enum = { + .items = ad4130_filter_modes_str, + .num_items = ARRAY_SIZE(ad4130_filter_modes_str), + .set = ad4130_set_filter_mode, + .get = ad4130_get_filter_mode, +}; + +static const struct iio_chan_spec_ext_info ad4130_filter_mode_ext_info[] = { + IIO_ENUM("filter_mode", IIO_SEPARATE, &ad4130_filter_mode_enum), + IIO_ENUM_AVAILABLE("filter_mode", IIO_SHARED_BY_TYPE, + &ad4130_filter_mode_enum), + { } +}; + +static const struct iio_chan_spec ad4130_channel_template = { + .type = IIO_VOLTAGE, + .indexed = 1, + .differential = 1, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_OFFSET) | + BIT(IIO_CHAN_INFO_SAMP_FREQ), + .info_mask_separate_available = BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_SAMP_FREQ), + .ext_info = ad4130_filter_mode_ext_info, + .scan_type = { + .sign = 'u', + .endianness = IIO_BE, + }, +}; + +static int ad4130_set_channel_pga(struct ad4130_state *st, unsigned int channel, + int val, int val2) +{ + struct ad4130_chan_info *chan_info = &st->chans_info[channel]; + struct ad4130_setup_info *setup_info = &chan_info->setup; + unsigned int pga, old_pga; + int ret = 0; + + for (pga = 0; pga < AD4130_MAX_PGA; pga++) + if (val == st->scale_tbls[setup_info->ref_sel][pga][0] && + val2 == st->scale_tbls[setup_info->ref_sel][pga][1]) + break; + + if (pga == AD4130_MAX_PGA) + return -EINVAL; + + mutex_lock(&st->lock); + if (pga == setup_info->pga) + goto out; + + old_pga = setup_info->pga; + setup_info->pga = pga; + + ret = ad4130_write_channel_setup(st, channel, false); + if (ret) + setup_info->pga = old_pga; + +out: + mutex_unlock(&st->lock); + + return ret; +} + +static int ad4130_set_channel_freq(struct ad4130_state *st, + unsigned int channel, int val, int val2) +{ + struct ad4130_chan_info *chan_info = &st->chans_info[channel]; + struct ad4130_setup_info *setup_info = &chan_info->setup; + unsigned int fs, old_fs; + int ret = 0; + + mutex_lock(&st->lock); + old_fs = setup_info->fs; + + ad4130_freq_to_fs(setup_info->filter_mode, val, val2, &fs); + + if (fs == setup_info->fs) + goto out; + + setup_info->fs = fs; + + ret = ad4130_write_channel_setup(st, channel, false); + if (ret) + setup_info->fs = old_fs; + +out: + mutex_unlock(&st->lock); + + return ret; +} + +static int _ad4130_read_sample(struct iio_dev *indio_dev, unsigned int channel, + int *val) +{ + struct ad4130_state *st = iio_priv(indio_dev); + int ret; + + ret = ad4130_set_channel_enable(st, channel, true); + if (ret) + return ret; + + reinit_completion(&st->completion); + + ret = ad4130_set_mode(st, AD4130_MODE_CONTINUOUS); + if (ret) + return ret; + + ret = wait_for_completion_timeout(&st->completion, + msecs_to_jiffies(1000)); + if (!ret) + return -ETIMEDOUT; + + ret = ad4130_set_mode(st, AD4130_MODE_IDLE); + if (ret) + return ret; + + ret = regmap_read(st->regmap, AD4130_DATA_REG, val); + if (ret) + return ret; + + ret = ad4130_set_channel_enable(st, channel, false); + if (ret) + return ret; + + return IIO_VAL_INT; +} + +static int ad4130_read_sample(struct iio_dev *indio_dev, unsigned int channel, + int *val) +{ + struct ad4130_state *st = iio_priv(indio_dev); + int ret; + + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) + return ret; + + mutex_lock(&st->lock); + ret = _ad4130_read_sample(indio_dev, channel, val); + mutex_unlock(&st->lock); + + iio_device_release_direct_mode(indio_dev); + + return ret; +} + +static int ad4130_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long info) +{ + struct ad4130_state *st = iio_priv(indio_dev); + unsigned int channel = chan->scan_index; + struct ad4130_setup_info *setup_info = &st->chans_info[channel].setup; + + switch (info) { + case IIO_CHAN_INFO_RAW: + return ad4130_read_sample(indio_dev, channel, val); + case IIO_CHAN_INFO_SCALE: + mutex_lock(&st->lock); + *val = st->scale_tbls[setup_info->ref_sel][setup_info->pga][0]; + *val2 = st->scale_tbls[setup_info->ref_sel][setup_info->pga][1]; + mutex_unlock(&st->lock); + + return IIO_VAL_INT_PLUS_NANO; + case IIO_CHAN_INFO_OFFSET: + *val = st->bipolar ? -BIT(chan->scan_type.realbits - 1) : 0; + + return IIO_VAL_INT; + case IIO_CHAN_INFO_SAMP_FREQ: + mutex_lock(&st->lock); + ad4130_fs_to_freq(setup_info->filter_mode, setup_info->fs, + val, val2); + mutex_unlock(&st->lock); + + return IIO_VAL_INT_PLUS_NANO; + default: + return -EINVAL; + } +} + +static int ad4130_read_avail(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int **vals, int *type, int *length, + long info) +{ + struct ad4130_state *st = iio_priv(indio_dev); + unsigned int channel = chan->scan_index; + struct ad4130_setup_info *setup_info = &st->chans_info[channel].setup; + const struct ad4130_filter_config *filter_config; + + switch (info) { + case IIO_CHAN_INFO_SCALE: + *vals = (int *)st->scale_tbls[setup_info->ref_sel]; + *length = ARRAY_SIZE(st->scale_tbls[setup_info->ref_sel]) * 2; + + *type = IIO_VAL_INT_PLUS_NANO; + + return IIO_AVAIL_LIST; + case IIO_CHAN_INFO_SAMP_FREQ: + mutex_lock(&st->lock); + filter_config = &ad4130_filter_configs[setup_info->filter_mode]; + mutex_unlock(&st->lock); + + *vals = (int *)filter_config->samp_freq_avail; + *length = filter_config->samp_freq_avail_len * 2; + *type = IIO_VAL_FRACTIONAL; + + return filter_config->samp_freq_avail_type; + default: + return -EINVAL; + } +} + +static int ad4130_write_raw_get_fmt(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + long info) +{ + switch (info) { + case IIO_CHAN_INFO_SCALE: + case IIO_CHAN_INFO_SAMP_FREQ: + return IIO_VAL_INT_PLUS_NANO; + default: + return -EINVAL; + } +} + +static int ad4130_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long info) +{ + struct ad4130_state *st = iio_priv(indio_dev); + unsigned int channel = chan->scan_index; + + switch (info) { + case IIO_CHAN_INFO_SCALE: + return ad4130_set_channel_pga(st, channel, val, val2); + case IIO_CHAN_INFO_SAMP_FREQ: + return ad4130_set_channel_freq(st, channel, val, val2); + default: + return -EINVAL; + } +} + +static int ad4130_reg_access(struct iio_dev *indio_dev, unsigned int reg, + unsigned int writeval, unsigned int *readval) +{ + struct ad4130_state *st = iio_priv(indio_dev); + + if (readval) + return regmap_read(st->regmap, reg, readval); + + return regmap_write(st->regmap, reg, writeval); +} + +static int ad4130_update_scan_mode(struct iio_dev *indio_dev, + const unsigned long *scan_mask) +{ + struct ad4130_state *st = iio_priv(indio_dev); + unsigned int channel; + unsigned int val = 0; + int ret; + + mutex_lock(&st->lock); + + for_each_set_bit(channel, scan_mask, indio_dev->num_channels) { + ret = ad4130_set_channel_enable(st, channel, true); + if (ret) + goto out; + + val++; + } + + st->num_enabled_channels = val; + +out: + mutex_unlock(&st->lock); + + return 0; +} + +static int ad4130_set_fifo_watermark(struct iio_dev *indio_dev, unsigned int val) +{ + struct ad4130_state *st = iio_priv(indio_dev); + unsigned int eff; + int ret; + + if (val > AD4130_FIFO_SIZE) + return -EINVAL; + + eff = val * st->num_enabled_channels; + if (eff > AD4130_FIFO_SIZE) + /* + * Always set watermark to a multiple of the number of + * enabled channels to avoid making the FIFO unaligned. + */ + eff = rounddown(AD4130_FIFO_SIZE, st->num_enabled_channels); + + mutex_lock(&st->lock); + + ret = regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG, + AD4130_FIFO_CONTROL_WM_MASK, + FIELD_PREP(AD4130_FIFO_CONTROL_WM_MASK, + ad4130_watermark_reg_val(eff))); + if (ret) + goto out; + + st->effective_watermark = eff; + st->watermark = val; + +out: + mutex_unlock(&st->lock); + + return ret; +} + +static const struct iio_info ad4130_info = { + .read_raw = ad4130_read_raw, + .read_avail = ad4130_read_avail, + .write_raw_get_fmt = ad4130_write_raw_get_fmt, + .write_raw = ad4130_write_raw, + .update_scan_mode = ad4130_update_scan_mode, + .hwfifo_set_watermark = ad4130_set_fifo_watermark, + .debugfs_reg_access = ad4130_reg_access, +}; + +static int ad4130_buffer_postenable(struct iio_dev *indio_dev) +{ + struct ad4130_state *st = iio_priv(indio_dev); + int ret; + + mutex_lock(&st->lock); + + ret = ad4130_set_watermark_interrupt_en(st, true); + if (ret) + goto out; + + ret = irq_set_irq_type(st->spi->irq, st->inv_irq_trigger); + if (ret) + goto out; + + ret = ad4130_set_fifo_mode(st, AD4130_FIFO_MODE_WM); + if (ret) + goto out; + + ret = ad4130_set_mode(st, AD4130_MODE_CONTINUOUS); + +out: + mutex_unlock(&st->lock); + + return ret; +} + +static int ad4130_buffer_predisable(struct iio_dev *indio_dev) +{ + struct ad4130_state *st = iio_priv(indio_dev); + unsigned int i; + int ret; + + mutex_lock(&st->lock); + + ret = ad4130_set_mode(st, AD4130_MODE_IDLE); + if (ret) + goto out; + + ret = irq_set_irq_type(st->spi->irq, st->irq_trigger); + if (ret) + goto out; + + ret = ad4130_set_fifo_mode(st, AD4130_FIFO_MODE_DISABLED); + if (ret) + goto out; + + ret = ad4130_set_watermark_interrupt_en(st, false); + if (ret) + goto out; + + /* + * update_scan_mode() is not called in the disable path, disable all + * channels here. + */ + for (i = 0; i < indio_dev->num_channels; i++) { + ret = ad4130_set_channel_enable(st, i, false); + if (ret) + goto out; + } + +out: + mutex_unlock(&st->lock); + + return ret; +} + +static const struct iio_buffer_setup_ops ad4130_buffer_ops = { + .postenable = ad4130_buffer_postenable, + .predisable = ad4130_buffer_predisable, +}; + +static ssize_t hwfifo_watermark_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct ad4130_state *st = iio_priv(dev_to_iio_dev(dev)); + unsigned int val; + + mutex_lock(&st->lock); + val = st->watermark; + mutex_unlock(&st->lock); + + return sysfs_emit(buf, "%d\n", val); +} + +static ssize_t hwfifo_enabled_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct ad4130_state *st = iio_priv(dev_to_iio_dev(dev)); + unsigned int val; + int ret; + + ret = regmap_read(st->regmap, AD4130_FIFO_CONTROL_REG, &val); + if (ret) + return ret; + + val = FIELD_GET(AD4130_FIFO_CONTROL_MODE_MASK, val); + + return sysfs_emit(buf, "%d\n", val != AD4130_FIFO_MODE_DISABLED); +} + +static ssize_t hwfifo_watermark_min_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "%s\n", "1"); +} + +static ssize_t hwfifo_watermark_max_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "%s\n", __stringify(AD4130_FIFO_SIZE)); +} + +static IIO_DEVICE_ATTR_RO(hwfifo_watermark_min, 0); +static IIO_DEVICE_ATTR_RO(hwfifo_watermark_max, 0); +static IIO_DEVICE_ATTR_RO(hwfifo_watermark, 0); +static IIO_DEVICE_ATTR_RO(hwfifo_enabled, 0); + +static const struct iio_dev_attr *ad4130_fifo_attributes[] = { + &iio_dev_attr_hwfifo_watermark_min, + &iio_dev_attr_hwfifo_watermark_max, + &iio_dev_attr_hwfifo_watermark, + &iio_dev_attr_hwfifo_enabled, + NULL +}; + +static int _ad4130_find_table_index(const unsigned int *tbl, size_t len, + unsigned int val) +{ + unsigned int i; + + for (i = 0; i < len; i++) + if (tbl[i] == val) + return i; + + return -EINVAL; +} + +#define ad4130_find_table_index(table, val) \ + _ad4130_find_table_index(table, ARRAY_SIZE(table), val) + +static int ad4130_get_ref_voltage(struct ad4130_state *st, + enum ad4130_ref_sel ref_sel) +{ + switch (ref_sel) { + case AD4130_REF_REFIN1: + return regulator_get_voltage(st->regulators[2].consumer); + case AD4130_REF_REFIN2: + return regulator_get_voltage(st->regulators[3].consumer); + case AD4130_REF_AVDD_AVSS: + return regulator_get_voltage(st->regulators[0].consumer); + case AD4130_REF_REFOUT_AVSS: + return st->int_ref_uv; + default: + return -EINVAL; + } +} + +static int ad4130_parse_fw_setup(struct ad4130_state *st, + struct fwnode_handle *child, + struct ad4130_setup_info *setup_info) +{ + struct device *dev = &st->spi->dev; + u32 tmp; + int ret; + + tmp = 0; + fwnode_property_read_u32(child, "adi,excitation-current-0-nanoamp", &tmp); + ret = ad4130_find_table_index(ad4130_iout_current_na_tbl, tmp); + if (ret < 0) + return dev_err_probe(dev, ret, + "Invalid excitation current %unA\n", tmp); + setup_info->iout0_val = ret; + + tmp = 0; + fwnode_property_read_u32(child, "adi,excitation-current-1-nanoamp", &tmp); + ret = ad4130_find_table_index(ad4130_iout_current_na_tbl, tmp); + if (ret < 0) + return dev_err_probe(dev, ret, + "Invalid excitation current %unA\n", tmp); + setup_info->iout1_val = ret; + + tmp = 0; + fwnode_property_read_u32(child, "adi,burnout-current-nanoamp", &tmp); + ret = ad4130_find_table_index(ad4130_burnout_current_na_tbl, tmp); + if (ret < 0) + return dev_err_probe(dev, ret, + "Invalid burnout current %unA\n", tmp); + setup_info->burnout = ret; + + setup_info->ref_bufp = fwnode_property_read_bool(child, "adi,buffered-positive"); + setup_info->ref_bufm = fwnode_property_read_bool(child, "adi,buffered-negative"); + + setup_info->ref_sel = AD4130_REF_REFIN1; + fwnode_property_read_u32(child, "adi,reference-select", + &setup_info->ref_sel); + if (setup_info->ref_sel >= AD4130_REF_SEL_MAX) + return dev_err_probe(dev, -EINVAL, + "Invalid reference selected %u\n", + setup_info->ref_sel); + + if (setup_info->ref_sel == AD4130_REF_REFOUT_AVSS) + st->int_ref_en = true; + + ret = ad4130_get_ref_voltage(st, setup_info->ref_sel); + if (ret < 0) + return dev_err_probe(dev, ret, "Cannot use reference %u\n", + setup_info->ref_sel); + + return 0; +} + +static int ad4130_validate_diff_channel(struct ad4130_state *st, u32 pin) +{ + struct device *dev = &st->spi->dev; + + if (pin >= AD4130_MAX_DIFF_INPUTS) + return dev_err_probe(dev, -EINVAL, + "Invalid differential channel %u\n", pin); + + if (pin >= AD4130_MAX_ANALOG_PINS) + return 0; + + if (st->pins_fn[pin] == AD4130_PIN_FN_SPECIAL) + return dev_err_probe(dev, -EINVAL, + "Pin %u already used with fn %u\n", pin, + st->pins_fn[pin]); + + st->pins_fn[pin] |= AD4130_PIN_FN_DIFF; + + return 0; +} + +static int ad4130_validate_diff_channels(struct ad4130_state *st, + u32 *pins, unsigned int len) +{ + unsigned int i; + int ret; + + for (i = 0; i < len; i++) { + ret = ad4130_validate_diff_channel(st, pins[i]); + if (ret) + return ret; + } + + return 0; +} + +static int ad4130_validate_excitation_pin(struct ad4130_state *st, u32 pin) +{ + struct device *dev = &st->spi->dev; + + if (pin >= AD4130_MAX_ANALOG_PINS) + return dev_err_probe(dev, -EINVAL, + "Invalid excitation pin %u\n", pin); + + if (st->pins_fn[pin] == AD4130_PIN_FN_SPECIAL) + return dev_err_probe(dev, -EINVAL, + "Pin %u already used with fn %u\n", pin, + st->pins_fn[pin]); + + st->pins_fn[pin] |= AD4130_PIN_FN_EXCITATION; + + return 0; +} + +static int ad4130_validate_vbias_pin(struct ad4130_state *st, u32 pin) +{ + struct device *dev = &st->spi->dev; + + if (pin >= AD4130_MAX_ANALOG_PINS) + return dev_err_probe(dev, -EINVAL, "Invalid vbias pin %u\n", + pin); + + if (st->pins_fn[pin] == AD4130_PIN_FN_SPECIAL) + return dev_err_probe(dev, -EINVAL, + "Pin %u already used with fn %u\n", pin, + st->pins_fn[pin]); + + st->pins_fn[pin] |= AD4130_PIN_FN_VBIAS; + + return 0; +} + +static int ad4130_validate_vbias_pins(struct ad4130_state *st, + u32 *pins, unsigned int len) +{ + unsigned int i; + int ret; + + for (i = 0; i < st->num_vbias_pins; i++) { + ret = ad4130_validate_vbias_pin(st, pins[i]); + if (ret) + return ret; + } + + return 0; +} + +static int ad4130_parse_fw_channel(struct iio_dev *indio_dev, + struct fwnode_handle *child) +{ + struct ad4130_state *st = iio_priv(indio_dev); + unsigned int resolution = ad4130_resolution(st); + unsigned int index = indio_dev->num_channels++; + struct device *dev = &st->spi->dev; + struct ad4130_chan_info *chan_info; + struct iio_chan_spec *chan; + u32 pins[2]; + int ret; + + if (index >= AD4130_MAX_CHANNELS) + return dev_err_probe(dev, -EINVAL, "Too many channels\n"); + + chan = &st->chans[index]; + chan_info = &st->chans_info[index]; + + *chan = ad4130_channel_template; + chan->scan_type.realbits = resolution; + chan->scan_type.storagebits = resolution; + chan->scan_index = index; + + chan_info->slot = AD4130_INVALID_SLOT; + chan_info->setup.fs = AD4130_FILTER_SELECT_MIN; + chan_info->initialized = true; + + ret = fwnode_property_read_u32_array(child, "diff-channels", pins, + ARRAY_SIZE(pins)); + if (ret) + return ret; + + ret = ad4130_validate_diff_channels(st, pins, ARRAY_SIZE(pins)); + if (ret) + return ret; + + chan->channel = pins[0]; + chan->channel2 = pins[1]; + + ret = ad4130_parse_fw_setup(st, child, &chan_info->setup); + if (ret) + return ret; + + fwnode_property_read_u32(child, "adi,excitation-pin-0", + &chan_info->iout0); + if (chan_info->setup.iout0_val != AD4130_IOUT_OFF) { + ret = ad4130_validate_excitation_pin(st, chan_info->iout0); + if (ret) + return ret; + } + + fwnode_property_read_u32(child, "adi,excitation-pin-1", + &chan_info->iout1); + if (chan_info->setup.iout1_val != AD4130_IOUT_OFF) { + ret = ad4130_validate_excitation_pin(st, chan_info->iout1); + if (ret) + return ret; + } + + return 0; +} + +static int ad4130_parse_fw_children(struct iio_dev *indio_dev) +{ + struct ad4130_state *st = iio_priv(indio_dev); + struct device *dev = &st->spi->dev; + struct fwnode_handle *child; + int ret; + + indio_dev->channels = st->chans; + + device_for_each_child_node(dev, child) { + ret = ad4130_parse_fw_channel(indio_dev, child); + if (ret) { + fwnode_handle_put(child); + return ret; + } + } + + return 0; +} + +static int ad4310_parse_fw(struct iio_dev *indio_dev) +{ + struct ad4130_state *st = iio_priv(indio_dev); + struct device *dev = &st->spi->dev; + u32 ext_clk_freq = AD4130_MCLK_FREQ_76_8KHZ; + unsigned int i; + int avdd_uv; + int irq; + int ret; + + st->mclk = devm_clk_get_optional(dev, "mclk"); + if (IS_ERR(st->mclk)) + return dev_err_probe(dev, PTR_ERR(st->mclk), + "Failed to get mclk\n"); + + st->int_pin_sel = AD4130_INT_PIN_INT; + + for (i = 0; i < ARRAY_SIZE(ad4130_int_pin_names); i++) { + irq = fwnode_irq_get_byname(dev_fwnode(dev), + ad4130_int_pin_names[i]); + if (irq > 0) { + st->int_pin_sel = i; + break; + } + } + + if (st->int_pin_sel == AD4130_INT_PIN_DOUT) + return dev_err_probe(dev, -EINVAL, + "Cannot use DOUT as interrupt pin\n"); + + if (st->int_pin_sel == AD4130_INT_PIN_P2) + st->pins_fn[AD4130_AIN3_P2] = AD4130_PIN_FN_SPECIAL; + + device_property_read_u32(dev, "adi,ext-clk-freq-hz", &ext_clk_freq); + if (ext_clk_freq != AD4130_MCLK_FREQ_153_6KHZ && + ext_clk_freq != AD4130_MCLK_FREQ_76_8KHZ) + return dev_err_probe(dev, -EINVAL, + "Invalid external clock frequency %u\n", + ext_clk_freq); + + if (st->mclk && ext_clk_freq == AD4130_MCLK_FREQ_153_6KHZ) + st->mclk_sel = AD4130_MCLK_153_6KHZ_EXT; + else if (st->mclk) + st->mclk_sel = AD4130_MCLK_76_8KHZ_EXT; + else + st->mclk_sel = AD4130_MCLK_76_8KHZ; + + if (st->int_pin_sel == AD4130_INT_PIN_CLK && + st->mclk_sel != AD4130_MCLK_76_8KHZ) + return dev_err_probe(dev, -EINVAL, + "Invalid clock %u for interrupt pin %u\n", + st->mclk_sel, st->int_pin_sel); + + st->int_ref_uv = AD4130_INT_REF_2_5V; + + /* + * When the AVDD supply is set to below 2.5V the internal reference of + * 1.25V should be selected. + * See datasheet page 37, section ADC REFERENCE. + */ + avdd_uv = regulator_get_voltage(st->regulators[0].consumer); + if (avdd_uv > 0 && avdd_uv < AD4130_INT_REF_2_5V) + st->int_ref_uv = AD4130_INT_REF_1_25V; + + st->bipolar = device_property_read_bool(dev, "adi,bipolar"); + + ret = device_property_count_u32(dev, "adi,vbias-pins"); + if (ret > 0) { + if (ret > AD4130_MAX_ANALOG_PINS) + return dev_err_probe(dev, -EINVAL, + "Too many vbias pins %u\n", ret); + + st->num_vbias_pins = ret; + + ret = device_property_read_u32_array(dev, "adi,vbias-pins", + st->vbias_pins, + st->num_vbias_pins); + if (ret) + return dev_err_probe(dev, ret, + "Failed to read vbias pins\n"); + + ret = ad4130_validate_vbias_pins(st, st->vbias_pins, + st->num_vbias_pins); + if (ret) + return ret; + } + + ret = ad4130_parse_fw_children(indio_dev); + if (ret) + return ret; + + return 0; +} + +static void ad4130_fill_scale_tbls(struct ad4130_state *st) +{ + unsigned int pow = ad4130_resolution(st) - st->bipolar; + unsigned int i, j; + + for (i = 0; i < AD4130_REF_SEL_MAX; i++) { + int ret; + u64 nv; + + ret = ad4130_get_ref_voltage(st, i); + if (ret < 0) + continue; + + nv = (u64)ret * NANO; + + for (j = 0; j < AD4130_MAX_PGA; j++) + st->scale_tbls[i][j][1] = div_u64(nv >> (pow + j), MILLI); + } +} + +static void ad4130_clk_disable_unprepare(void *clk) +{ + clk_disable_unprepare(clk); +} + +static int ad4130_set_mclk_sel(struct ad4130_state *st, + enum ad4130_mclk_sel mclk_sel) +{ + return regmap_update_bits(st->regmap, AD4130_ADC_CONTROL_REG, + AD4130_ADC_CONTROL_MCLK_SEL_MASK, + FIELD_PREP(AD4130_ADC_CONTROL_MCLK_SEL_MASK, + mclk_sel)); +} + +static unsigned long ad4130_int_clk_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + return AD4130_MCLK_FREQ_76_8KHZ; +} + +static int ad4130_int_clk_is_enabled(struct clk_hw *hw) +{ + struct ad4130_state *st = container_of(hw, struct ad4130_state, int_clk_hw); + + return st->mclk_sel == AD4130_MCLK_76_8KHZ_OUT; +} + +static int ad4130_int_clk_prepare(struct clk_hw *hw) +{ + struct ad4130_state *st = container_of(hw, struct ad4130_state, int_clk_hw); + int ret; + + ret = ad4130_set_mclk_sel(st, AD4130_MCLK_76_8KHZ_OUT); + if (ret) + return ret; + + st->mclk_sel = AD4130_MCLK_76_8KHZ_OUT; + + return 0; +} + +static void ad4130_int_clk_unprepare(struct clk_hw *hw) +{ + struct ad4130_state *st = container_of(hw, struct ad4130_state, int_clk_hw); + int ret; + + ret = ad4130_set_mclk_sel(st, AD4130_MCLK_76_8KHZ); + if (ret) + return; + + st->mclk_sel = AD4130_MCLK_76_8KHZ; +} + +static const struct clk_ops ad4130_int_clk_ops = { + .recalc_rate = ad4130_int_clk_recalc_rate, + .is_enabled = ad4130_int_clk_is_enabled, + .prepare = ad4130_int_clk_prepare, + .unprepare = ad4130_int_clk_unprepare, +}; + +static void ad4130_clk_del_provider(void *of_node) +{ + of_clk_del_provider(of_node); +} + +static int ad4130_setup_int_clk(struct ad4130_state *st) +{ + struct device *dev = &st->spi->dev; + struct device_node *of_node = dev_of_node(dev); + struct clk_init_data init; + const char *clk_name; + struct clk *clk; + int ret; + + if (st->int_pin_sel == AD4130_INT_PIN_CLK || + st->mclk_sel != AD4130_MCLK_76_8KHZ) + return 0; + + if (!of_node) + return 0; + + clk_name = of_node->name; + of_property_read_string(of_node, "clock-output-names", &clk_name); + + init.name = clk_name; + init.ops = &ad4130_int_clk_ops; + + st->int_clk_hw.init = &init; + clk = devm_clk_register(dev, &st->int_clk_hw); + if (IS_ERR(clk)) + return PTR_ERR(clk); + + ret = of_clk_add_provider(of_node, of_clk_src_simple_get, clk); + if (ret) + return ret; + + return devm_add_action_or_reset(dev, ad4130_clk_del_provider, of_node); +} + +static int ad4130_setup(struct iio_dev *indio_dev) +{ + struct ad4130_state *st = iio_priv(indio_dev); + struct device *dev = &st->spi->dev; + unsigned int int_ref_val; + unsigned long rate = AD4130_MCLK_FREQ_76_8KHZ; + unsigned int val; + unsigned int i; + int ret; + + if (st->mclk_sel == AD4130_MCLK_153_6KHZ_EXT) + rate = AD4130_MCLK_FREQ_153_6KHZ; + + ret = clk_set_rate(st->mclk, rate); + if (ret) + return ret; + + ret = clk_prepare_enable(st->mclk); + if (ret) + return ret; + + ret = devm_add_action_or_reset(dev, ad4130_clk_disable_unprepare, + st->mclk); + if (ret) + return ret; + + if (st->int_ref_uv == AD4130_INT_REF_2_5V) + int_ref_val = AD4130_INT_REF_VAL_2_5V; + else + int_ref_val = AD4130_INT_REF_VAL_1_25V; + + /* Switch to SPI 4-wire mode. */ + val = FIELD_PREP(AD4130_ADC_CONTROL_CSB_EN_MASK, 1); + val |= FIELD_PREP(AD4130_ADC_CONTROL_BIPOLAR_MASK, st->bipolar); + val |= FIELD_PREP(AD4130_ADC_CONTROL_INT_REF_EN_MASK, st->int_ref_en); + val |= FIELD_PREP(AD4130_ADC_CONTROL_MODE_MASK, AD4130_MODE_IDLE); + val |= FIELD_PREP(AD4130_ADC_CONTROL_MCLK_SEL_MASK, st->mclk_sel); + val |= FIELD_PREP(AD4130_ADC_CONTROL_INT_REF_VAL_MASK, int_ref_val); + + ret = regmap_write(st->regmap, AD4130_ADC_CONTROL_REG, val); + if (ret) + return ret; + + /* + * Configure all GPIOs for output. If configured, the interrupt function + * of P2 takes priority over the GPIO out function. + */ + val = AD4130_IO_CONTROL_GPIO_CTRL_MASK; + val |= FIELD_PREP(AD4130_IO_CONTROL_INT_PIN_SEL_MASK, st->int_pin_sel); + + ret = regmap_write(st->regmap, AD4130_IO_CONTROL_REG, val); + if (ret) + return ret; + + val = 0; + for (i = 0; i < st->num_vbias_pins; i++) + val |= BIT(st->vbias_pins[i]); + + ret = regmap_write(st->regmap, AD4130_VBIAS_REG, val); + if (ret) + return ret; + + ret = regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG, + AD4130_FIFO_CONTROL_HEADER_MASK, 0); + if (ret) + return ret; + + /* FIFO watermark interrupt starts out as enabled, disable it. */ + ret = ad4130_set_watermark_interrupt_en(st, false); + if (ret) + return ret; + + /* Setup channels. */ + for (i = 0; i < indio_dev->num_channels; i++) { + struct ad4130_chan_info *chan_info = &st->chans_info[i]; + struct iio_chan_spec *chan = &st->chans[i]; + unsigned int val; + + val = FIELD_PREP(AD4130_CHANNEL_AINP_MASK, chan->channel) | + FIELD_PREP(AD4130_CHANNEL_AINM_MASK, chan->channel2) | + FIELD_PREP(AD4130_CHANNEL_IOUT1_MASK, chan_info->iout0) | + FIELD_PREP(AD4130_CHANNEL_IOUT2_MASK, chan_info->iout1); + + ret = regmap_write(st->regmap, AD4130_CHANNEL_X_REG(i), val); + if (ret) + return ret; + } + + return 0; +} + +static int ad4130_soft_reset(struct ad4130_state *st) +{ + int ret; + + ret = spi_write(st->spi, st->reset_buf, sizeof(st->reset_buf)); + if (ret) + return ret; + + fsleep(AD4130_RESET_SLEEP_US); + + return 0; +} + +static void ad4130_disable_regulators(void *data) +{ + struct ad4130_state *st = data; + + regulator_bulk_disable(ARRAY_SIZE(st->regulators), st->regulators); +} + +static int ad4130_probe(struct spi_device *spi) +{ + struct device *dev = &spi->dev; + struct iio_dev *indio_dev; + struct ad4130_state *st; + int ret; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + + memset(st->reset_buf, 0xff, sizeof(st->reset_buf)); + init_completion(&st->completion); + mutex_init(&st->lock); + st->spi = spi; + + /* + * Xfer: [ XFR1 ] [ XFR2 ] + * Master: 0x7D N ...................... + * Slave: ...... DATA1 DATA2 ... DATAN + */ + st->fifo_tx_buf[0] = AD4130_COMMS_READ_MASK | AD4130_FIFO_DATA_REG; + st->fifo_xfer[0].tx_buf = st->fifo_tx_buf; + st->fifo_xfer[0].len = sizeof(st->fifo_tx_buf); + st->fifo_xfer[1].rx_buf = st->fifo_rx_buf; + spi_message_init_with_transfers(&st->fifo_msg, st->fifo_xfer, + ARRAY_SIZE(st->fifo_xfer)); + + indio_dev->name = AD4130_NAME; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->info = &ad4130_info; + + st->regmap = devm_regmap_init(dev, NULL, st, &ad4130_regmap_config); + if (IS_ERR(st->regmap)) + return PTR_ERR(st->regmap); + + st->regulators[0].supply = "avdd"; + st->regulators[1].supply = "iovdd"; + st->regulators[2].supply = "refin1"; + st->regulators[3].supply = "refin2"; + + ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(st->regulators), + st->regulators); + if (ret) + return dev_err_probe(dev, ret, "Failed to get regulators\n"); + + ret = regulator_bulk_enable(ARRAY_SIZE(st->regulators), st->regulators); + if (ret) + return dev_err_probe(dev, ret, "Failed to enable regulators\n"); + + ret = devm_add_action_or_reset(dev, ad4130_disable_regulators, st); + if (ret) + return dev_err_probe(dev, ret, + "Failed to add regulators disable action\n"); + + ret = ad4130_soft_reset(st); + if (ret) + return ret; + + ret = ad4310_parse_fw(indio_dev); + if (ret) + return ret; + + ret = ad4130_setup(indio_dev); + if (ret) + return ret; + + ret = ad4130_setup_int_clk(st); + if (ret) + return ret; + + ad4130_fill_scale_tbls(st); + + st->gc.owner = THIS_MODULE; + st->gc.label = AD4130_NAME; + st->gc.base = -1; + st->gc.ngpio = AD4130_MAX_GPIOS; + st->gc.parent = dev; + st->gc.can_sleep = true; + st->gc.init_valid_mask = ad4130_gpio_init_valid_mask; + st->gc.get_direction = ad4130_gpio_get_direction; + st->gc.set = ad4130_gpio_set; + + ret = devm_gpiochip_add_data(dev, &st->gc, st); + if (ret) + return ret; + + ret = devm_iio_kfifo_buffer_setup_ext(dev, indio_dev, + &ad4130_buffer_ops, + ad4130_fifo_attributes); + if (ret) + return ret; + + ret = devm_request_threaded_irq(dev, spi->irq, NULL, + ad4130_irq_handler, IRQF_ONESHOT, + indio_dev->name, indio_dev); + if (ret) + return dev_err_probe(dev, ret, "Failed to request irq\n"); + + /* + * When the chip enters FIFO mode, IRQ polarity is inverted. + * When the chip exits FIFO mode, IRQ polarity returns to normal. + * See datasheet pages: 65, FIFO Watermark Interrupt section, + * and 71, Bit Descriptions for STATUS Register, RDYB. + * Cache the normal and inverted IRQ triggers to set them when + * entering and exiting FIFO mode. + */ + st->irq_trigger = irq_get_trigger_type(spi->irq); + if (st->irq_trigger & IRQF_TRIGGER_RISING) + st->inv_irq_trigger = IRQF_TRIGGER_FALLING; + else if (st->irq_trigger & IRQF_TRIGGER_FALLING) + st->inv_irq_trigger = IRQF_TRIGGER_RISING; + else + return dev_err_probe(dev, -EINVAL, "Invalid irq flags: %u\n", + st->irq_trigger); + + return devm_iio_device_register(dev, indio_dev); +} + +static const struct of_device_id ad4130_of_match[] = { + { + .compatible = "adi,ad4130", + }, + { } +}; +MODULE_DEVICE_TABLE(of, ad4130_of_match); + +static struct spi_driver ad4130_driver = { + .driver = { + .name = AD4130_NAME, + .of_match_table = ad4130_of_match, + }, + .probe = ad4130_probe, +}; +module_spi_driver(ad4130_driver); + +MODULE_AUTHOR("Cosmin Tanislav <cosmin.tanislav@analog.com>"); +MODULE_DESCRIPTION("Analog Devices AD4130 SPI driver"); +MODULE_LICENSE("GPL"); |