diff options
Diffstat (limited to 'drivers/iio/adc/ad7192.c')
| -rw-r--r-- | drivers/iio/adc/ad7192.c | 1034 |
1 files changed, 1034 insertions, 0 deletions
diff --git a/drivers/iio/adc/ad7192.c b/drivers/iio/adc/ad7192.c new file mode 100644 index 000000000000..02981f3d1794 --- /dev/null +++ b/drivers/iio/adc/ad7192.c @@ -0,0 +1,1034 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * AD7190 AD7192 AD7193 AD7195 SPI ADC driver + * + * Copyright 2011-2015 Analog Devices Inc. + */ + +#include <linux/interrupt.h> +#include <linux/clk.h> +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/sysfs.h> +#include <linux/spi/spi.h> +#include <linux/regulator/consumer.h> +#include <linux/err.h> +#include <linux/sched.h> +#include <linux/delay.h> +#include <linux/of_device.h> + +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> +#include <linux/iio/buffer.h> +#include <linux/iio/trigger.h> +#include <linux/iio/trigger_consumer.h> +#include <linux/iio/triggered_buffer.h> +#include <linux/iio/adc/ad_sigma_delta.h> + +/* Registers */ +#define AD7192_REG_COMM 0 /* Communications Register (WO, 8-bit) */ +#define AD7192_REG_STAT 0 /* Status Register (RO, 8-bit) */ +#define AD7192_REG_MODE 1 /* Mode Register (RW, 24-bit */ +#define AD7192_REG_CONF 2 /* Configuration Register (RW, 24-bit) */ +#define AD7192_REG_DATA 3 /* Data Register (RO, 24/32-bit) */ +#define AD7192_REG_ID 4 /* ID Register (RO, 8-bit) */ +#define AD7192_REG_GPOCON 5 /* GPOCON Register (RO, 8-bit) */ +#define AD7192_REG_OFFSET 6 /* Offset Register (RW, 16-bit */ + /* (AD7792)/24-bit (AD7192)) */ +#define AD7192_REG_FULLSALE 7 /* Full-Scale Register */ + /* (RW, 16-bit (AD7792)/24-bit (AD7192)) */ + +/* Communications Register Bit Designations (AD7192_REG_COMM) */ +#define AD7192_COMM_WEN BIT(7) /* Write Enable */ +#define AD7192_COMM_WRITE 0 /* Write Operation */ +#define AD7192_COMM_READ BIT(6) /* Read Operation */ +#define AD7192_COMM_ADDR(x) (((x) & 0x7) << 3) /* Register Address */ +#define AD7192_COMM_CREAD BIT(2) /* Continuous Read of Data Register */ + +/* Status Register Bit Designations (AD7192_REG_STAT) */ +#define AD7192_STAT_RDY BIT(7) /* Ready */ +#define AD7192_STAT_ERR BIT(6) /* Error (Overrange, Underrange) */ +#define AD7192_STAT_NOREF BIT(5) /* Error no external reference */ +#define AD7192_STAT_PARITY BIT(4) /* Parity */ +#define AD7192_STAT_CH3 BIT(2) /* Channel 3 */ +#define AD7192_STAT_CH2 BIT(1) /* Channel 2 */ +#define AD7192_STAT_CH1 BIT(0) /* Channel 1 */ + +/* Mode Register Bit Designations (AD7192_REG_MODE) */ +#define AD7192_MODE_SEL(x) (((x) & 0x7) << 21) /* Operation Mode Select */ +#define AD7192_MODE_SEL_MASK (0x7 << 21) /* Operation Mode Select Mask */ +#define AD7192_MODE_DAT_STA BIT(20) /* Status Register transmission */ +#define AD7192_MODE_CLKSRC(x) (((x) & 0x3) << 18) /* Clock Source Select */ +#define AD7192_MODE_SINC3 BIT(15) /* SINC3 Filter Select */ +#define AD7192_MODE_ACX BIT(14) /* AC excitation enable(AD7195 only)*/ +#define AD7192_MODE_ENPAR BIT(13) /* Parity Enable */ +#define AD7192_MODE_CLKDIV BIT(12) /* Clock divide by 2 (AD7190/2 only)*/ +#define AD7192_MODE_SCYCLE BIT(11) /* Single cycle conversion */ +#define AD7192_MODE_REJ60 BIT(10) /* 50/60Hz notch filter */ +#define AD7192_MODE_RATE(x) ((x) & 0x3FF) /* Filter Update Rate Select */ + +/* Mode Register: AD7192_MODE_SEL options */ +#define AD7192_MODE_CONT 0 /* Continuous Conversion Mode */ +#define AD7192_MODE_SINGLE 1 /* Single Conversion Mode */ +#define AD7192_MODE_IDLE 2 /* Idle Mode */ +#define AD7192_MODE_PWRDN 3 /* Power-Down Mode */ +#define AD7192_MODE_CAL_INT_ZERO 4 /* Internal Zero-Scale Calibration */ +#define AD7192_MODE_CAL_INT_FULL 5 /* Internal Full-Scale Calibration */ +#define AD7192_MODE_CAL_SYS_ZERO 6 /* System Zero-Scale Calibration */ +#define AD7192_MODE_CAL_SYS_FULL 7 /* System Full-Scale Calibration */ + +/* Mode Register: AD7192_MODE_CLKSRC options */ +#define AD7192_CLK_EXT_MCLK1_2 0 /* External 4.92 MHz Clock connected*/ + /* from MCLK1 to MCLK2 */ +#define AD7192_CLK_EXT_MCLK2 1 /* External Clock applied to MCLK2 */ +#define AD7192_CLK_INT 2 /* Internal 4.92 MHz Clock not */ + /* available at the MCLK2 pin */ +#define AD7192_CLK_INT_CO 3 /* Internal 4.92 MHz Clock available*/ + /* at the MCLK2 pin */ + +/* Configuration Register Bit Designations (AD7192_REG_CONF) */ + +#define AD7192_CONF_CHOP BIT(23) /* CHOP enable */ +#define AD7192_CONF_REFSEL BIT(20) /* REFIN1/REFIN2 Reference Select */ +#define AD7192_CONF_CHAN(x) ((x) << 8) /* Channel select */ +#define AD7192_CONF_CHAN_MASK (0x7FF << 8) /* Channel select mask */ +#define AD7192_CONF_BURN BIT(7) /* Burnout current enable */ +#define AD7192_CONF_REFDET BIT(6) /* Reference detect enable */ +#define AD7192_CONF_BUF BIT(4) /* Buffered Mode Enable */ +#define AD7192_CONF_UNIPOLAR BIT(3) /* Unipolar/Bipolar Enable */ +#define AD7192_CONF_GAIN(x) ((x) & 0x7) /* Gain Select */ + +#define AD7192_CH_AIN1P_AIN2M BIT(0) /* AIN1(+) - AIN2(-) */ +#define AD7192_CH_AIN3P_AIN4M BIT(1) /* AIN3(+) - AIN4(-) */ +#define AD7192_CH_TEMP BIT(2) /* Temp Sensor */ +#define AD7192_CH_AIN2P_AIN2M BIT(3) /* AIN2(+) - AIN2(-) */ +#define AD7192_CH_AIN1 BIT(4) /* AIN1 - AINCOM */ +#define AD7192_CH_AIN2 BIT(5) /* AIN2 - AINCOM */ +#define AD7192_CH_AIN3 BIT(6) /* AIN3 - AINCOM */ +#define AD7192_CH_AIN4 BIT(7) /* AIN4 - AINCOM */ + +#define AD7193_CH_AIN1P_AIN2M 0x001 /* AIN1(+) - AIN2(-) */ +#define AD7193_CH_AIN3P_AIN4M 0x002 /* AIN3(+) - AIN4(-) */ +#define AD7193_CH_AIN5P_AIN6M 0x004 /* AIN5(+) - AIN6(-) */ +#define AD7193_CH_AIN7P_AIN8M 0x008 /* AIN7(+) - AIN8(-) */ +#define AD7193_CH_TEMP 0x100 /* Temp senseor */ +#define AD7193_CH_AIN2P_AIN2M 0x200 /* AIN2(+) - AIN2(-) */ +#define AD7193_CH_AIN1 0x401 /* AIN1 - AINCOM */ +#define AD7193_CH_AIN2 0x402 /* AIN2 - AINCOM */ +#define AD7193_CH_AIN3 0x404 /* AIN3 - AINCOM */ +#define AD7193_CH_AIN4 0x408 /* AIN4 - AINCOM */ +#define AD7193_CH_AIN5 0x410 /* AIN5 - AINCOM */ +#define AD7193_CH_AIN6 0x420 /* AIN6 - AINCOM */ +#define AD7193_CH_AIN7 0x440 /* AIN7 - AINCOM */ +#define AD7193_CH_AIN8 0x480 /* AIN7 - AINCOM */ +#define AD7193_CH_AINCOM 0x600 /* AINCOM - AINCOM */ + +/* ID Register Bit Designations (AD7192_REG_ID) */ +#define ID_AD7190 0x4 +#define ID_AD7192 0x0 +#define ID_AD7193 0x2 +#define ID_AD7195 0x6 +#define AD7192_ID_MASK 0x0F + +/* GPOCON Register Bit Designations (AD7192_REG_GPOCON) */ +#define AD7192_GPOCON_BPDSW BIT(6) /* Bridge power-down switch enable */ +#define AD7192_GPOCON_GP32EN BIT(5) /* Digital Output P3 and P2 enable */ +#define AD7192_GPOCON_GP10EN BIT(4) /* Digital Output P1 and P0 enable */ +#define AD7192_GPOCON_P3DAT BIT(3) /* P3 state */ +#define AD7192_GPOCON_P2DAT BIT(2) /* P2 state */ +#define AD7192_GPOCON_P1DAT BIT(1) /* P1 state */ +#define AD7192_GPOCON_P0DAT BIT(0) /* P0 state */ + +#define AD7192_EXT_FREQ_MHZ_MIN 2457600 +#define AD7192_EXT_FREQ_MHZ_MAX 5120000 +#define AD7192_INT_FREQ_MHZ 4915200 + +#define AD7192_NO_SYNC_FILTER 1 +#define AD7192_SYNC3_FILTER 3 +#define AD7192_SYNC4_FILTER 4 + +/* NOTE: + * The AD7190/2/5 features a dual use data out ready DOUT/RDY output. + * In order to avoid contentions on the SPI bus, it's therefore necessary + * to use spi bus locking. + * + * The DOUT/RDY output must also be wired to an interrupt capable GPIO. + */ + +enum { + AD7192_SYSCALIB_ZERO_SCALE, + AD7192_SYSCALIB_FULL_SCALE, +}; + +struct ad7192_state { + struct regulator *avdd; + struct regulator *dvdd; + struct clk *mclk; + u16 int_vref_mv; + u32 fclk; + u32 f_order; + u32 mode; + u32 conf; + u32 scale_avail[8][2]; + u8 gpocon; + u8 devid; + u8 clock_sel; + struct mutex lock; /* protect sensor state */ + u8 syscalib_mode[8]; + + struct ad_sigma_delta sd; +}; + +static const char * const ad7192_syscalib_modes[] = { + [AD7192_SYSCALIB_ZERO_SCALE] = "zero_scale", + [AD7192_SYSCALIB_FULL_SCALE] = "full_scale", +}; + +static int ad7192_set_syscalib_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + unsigned int mode) +{ + struct ad7192_state *st = iio_priv(indio_dev); + + st->syscalib_mode[chan->channel] = mode; + + return 0; +} + +static int ad7192_get_syscalib_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan) +{ + struct ad7192_state *st = iio_priv(indio_dev); + + return st->syscalib_mode[chan->channel]; +} + +static ssize_t ad7192_write_syscalib(struct iio_dev *indio_dev, + uintptr_t private, + const struct iio_chan_spec *chan, + const char *buf, size_t len) +{ + struct ad7192_state *st = iio_priv(indio_dev); + bool sys_calib; + int ret, temp; + + ret = strtobool(buf, &sys_calib); + if (ret) + return ret; + + temp = st->syscalib_mode[chan->channel]; + if (sys_calib) { + if (temp == AD7192_SYSCALIB_ZERO_SCALE) + ret = ad_sd_calibrate(&st->sd, AD7192_MODE_CAL_SYS_ZERO, + chan->address); + else + ret = ad_sd_calibrate(&st->sd, AD7192_MODE_CAL_SYS_FULL, + chan->address); + } + + return ret ? ret : len; +} + +static const struct iio_enum ad7192_syscalib_mode_enum = { + .items = ad7192_syscalib_modes, + .num_items = ARRAY_SIZE(ad7192_syscalib_modes), + .set = ad7192_set_syscalib_mode, + .get = ad7192_get_syscalib_mode +}; + +static const struct iio_chan_spec_ext_info ad7192_calibsys_ext_info[] = { + { + .name = "sys_calibration", + .write = ad7192_write_syscalib, + .shared = IIO_SEPARATE, + }, + IIO_ENUM("sys_calibration_mode", IIO_SEPARATE, + &ad7192_syscalib_mode_enum), + IIO_ENUM_AVAILABLE("sys_calibration_mode", &ad7192_syscalib_mode_enum), + {} +}; + +static struct ad7192_state *ad_sigma_delta_to_ad7192(struct ad_sigma_delta *sd) +{ + return container_of(sd, struct ad7192_state, sd); +} + +static int ad7192_set_channel(struct ad_sigma_delta *sd, unsigned int channel) +{ + struct ad7192_state *st = ad_sigma_delta_to_ad7192(sd); + + st->conf &= ~AD7192_CONF_CHAN_MASK; + st->conf |= AD7192_CONF_CHAN(channel); + + return ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf); +} + +static int ad7192_set_mode(struct ad_sigma_delta *sd, + enum ad_sigma_delta_mode mode) +{ + struct ad7192_state *st = ad_sigma_delta_to_ad7192(sd); + + st->mode &= ~AD7192_MODE_SEL_MASK; + st->mode |= AD7192_MODE_SEL(mode); + + return ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode); +} + +static const struct ad_sigma_delta_info ad7192_sigma_delta_info = { + .set_channel = ad7192_set_channel, + .set_mode = ad7192_set_mode, + .has_registers = true, + .addr_shift = 3, + .read_mask = BIT(6), +}; + +static const struct ad_sd_calib_data ad7192_calib_arr[8] = { + {AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN1}, + {AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN1}, + {AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN2}, + {AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN2}, + {AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN3}, + {AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN3}, + {AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN4}, + {AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN4} +}; + +static int ad7192_calibrate_all(struct ad7192_state *st) +{ + return ad_sd_calibrate_all(&st->sd, ad7192_calib_arr, + ARRAY_SIZE(ad7192_calib_arr)); +} + +static inline bool ad7192_valid_external_frequency(u32 freq) +{ + return (freq >= AD7192_EXT_FREQ_MHZ_MIN && + freq <= AD7192_EXT_FREQ_MHZ_MAX); +} + +static int ad7192_of_clock_select(struct ad7192_state *st) +{ + struct device_node *np = st->sd.spi->dev.of_node; + unsigned int clock_sel; + + clock_sel = AD7192_CLK_INT; + + /* use internal clock */ + if (PTR_ERR(st->mclk) == -ENOENT) { + if (of_property_read_bool(np, "adi,int-clock-output-enable")) + clock_sel = AD7192_CLK_INT_CO; + } else { + if (of_property_read_bool(np, "adi,clock-xtal")) + clock_sel = AD7192_CLK_EXT_MCLK1_2; + else + clock_sel = AD7192_CLK_EXT_MCLK2; + } + + return clock_sel; +} + +static int ad7192_setup(struct ad7192_state *st, struct device_node *np) +{ + struct iio_dev *indio_dev = spi_get_drvdata(st->sd.spi); + bool rej60_en, refin2_en; + bool buf_en, bipolar, burnout_curr_en; + unsigned long long scale_uv; + int i, ret, id; + + /* reset the serial interface */ + ret = ad_sd_reset(&st->sd, 48); + if (ret < 0) + return ret; + usleep_range(500, 1000); /* Wait for at least 500us */ + + /* write/read test for device presence */ + ret = ad_sd_read_reg(&st->sd, AD7192_REG_ID, 1, &id); + if (ret) + return ret; + + id &= AD7192_ID_MASK; + + if (id != st->devid) + dev_warn(&st->sd.spi->dev, "device ID query failed (0x%X)\n", + id); + + st->mode = AD7192_MODE_SEL(AD7192_MODE_IDLE) | + AD7192_MODE_CLKSRC(st->clock_sel) | + AD7192_MODE_RATE(480); + + st->conf = AD7192_CONF_GAIN(0); + + rej60_en = of_property_read_bool(np, "adi,rejection-60-Hz-enable"); + if (rej60_en) + st->mode |= AD7192_MODE_REJ60; + + refin2_en = of_property_read_bool(np, "adi,refin2-pins-enable"); + if (refin2_en && st->devid != ID_AD7195) + st->conf |= AD7192_CONF_REFSEL; + + st->conf &= ~AD7192_CONF_CHOP; + st->f_order = AD7192_NO_SYNC_FILTER; + + buf_en = of_property_read_bool(np, "adi,buffer-enable"); + if (buf_en) + st->conf |= AD7192_CONF_BUF; + + bipolar = of_property_read_bool(np, "bipolar"); + if (!bipolar) + st->conf |= AD7192_CONF_UNIPOLAR; + + burnout_curr_en = of_property_read_bool(np, + "adi,burnout-currents-enable"); + if (burnout_curr_en && buf_en) { + st->conf |= AD7192_CONF_BURN; + } else if (burnout_curr_en) { + dev_warn(&st->sd.spi->dev, + "Can't enable burnout currents: see CHOP or buffer\n"); + } + + ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode); + if (ret) + return ret; + + ret = ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf); + if (ret) + return ret; + + ret = ad7192_calibrate_all(st); + if (ret) + return ret; + + /* Populate available ADC input ranges */ + for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++) { + scale_uv = ((u64)st->int_vref_mv * 100000000) + >> (indio_dev->channels[0].scan_type.realbits - + ((st->conf & AD7192_CONF_UNIPOLAR) ? 0 : 1)); + scale_uv >>= i; + + st->scale_avail[i][1] = do_div(scale_uv, 100000000) * 10; + st->scale_avail[i][0] = scale_uv; + } + + return 0; +} + +static ssize_t ad7192_show_ac_excitation(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct ad7192_state *st = iio_priv(indio_dev); + + return sprintf(buf, "%d\n", !!(st->mode & AD7192_MODE_ACX)); +} + +static ssize_t ad7192_show_bridge_switch(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct ad7192_state *st = iio_priv(indio_dev); + + return sprintf(buf, "%d\n", !!(st->gpocon & AD7192_GPOCON_BPDSW)); +} + +static ssize_t ad7192_set(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct ad7192_state *st = iio_priv(indio_dev); + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + int ret; + bool val; + + ret = strtobool(buf, &val); + if (ret < 0) + return ret; + + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) + return ret; + + switch ((u32)this_attr->address) { + case AD7192_REG_GPOCON: + if (val) + st->gpocon |= AD7192_GPOCON_BPDSW; + else + st->gpocon &= ~AD7192_GPOCON_BPDSW; + + ad_sd_write_reg(&st->sd, AD7192_REG_GPOCON, 1, st->gpocon); + break; + case AD7192_REG_MODE: + if (val) + st->mode |= AD7192_MODE_ACX; + else + st->mode &= ~AD7192_MODE_ACX; + + ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode); + break; + default: + ret = -EINVAL; + } + + iio_device_release_direct_mode(indio_dev); + + return ret ? ret : len; +} + +static void ad7192_get_available_filter_freq(struct ad7192_state *st, + int *freq) +{ + unsigned int fadc; + + /* Formulas for filter at page 25 of the datasheet */ + fadc = DIV_ROUND_CLOSEST(st->fclk, + AD7192_SYNC4_FILTER * AD7192_MODE_RATE(st->mode)); + freq[0] = DIV_ROUND_CLOSEST(fadc * 240, 1024); + + fadc = DIV_ROUND_CLOSEST(st->fclk, + AD7192_SYNC3_FILTER * AD7192_MODE_RATE(st->mode)); + freq[1] = DIV_ROUND_CLOSEST(fadc * 240, 1024); + + fadc = DIV_ROUND_CLOSEST(st->fclk, AD7192_MODE_RATE(st->mode)); + freq[2] = DIV_ROUND_CLOSEST(fadc * 230, 1024); + freq[3] = DIV_ROUND_CLOSEST(fadc * 272, 1024); +} + +static ssize_t ad7192_show_filter_avail(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct ad7192_state *st = iio_priv(indio_dev); + unsigned int freq_avail[4], i; + size_t len = 0; + + ad7192_get_available_filter_freq(st, freq_avail); + + for (i = 0; i < ARRAY_SIZE(freq_avail); i++) + len += scnprintf(buf + len, PAGE_SIZE - len, + "%d.%d ", freq_avail[i] / 1000, + freq_avail[i] % 1000); + + buf[len - 1] = '\n'; + + return len; +} + +static IIO_DEVICE_ATTR(filter_low_pass_3db_frequency_available, + 0444, ad7192_show_filter_avail, NULL, 0); + +static IIO_DEVICE_ATTR(bridge_switch_en, 0644, + ad7192_show_bridge_switch, ad7192_set, + AD7192_REG_GPOCON); + +static IIO_DEVICE_ATTR(ac_excitation_en, 0644, + ad7192_show_ac_excitation, ad7192_set, + AD7192_REG_MODE); + +static struct attribute *ad7192_attributes[] = { + &iio_dev_attr_filter_low_pass_3db_frequency_available.dev_attr.attr, + &iio_dev_attr_bridge_switch_en.dev_attr.attr, + &iio_dev_attr_ac_excitation_en.dev_attr.attr, + NULL +}; + +static const struct attribute_group ad7192_attribute_group = { + .attrs = ad7192_attributes, +}; + +static struct attribute *ad7195_attributes[] = { + &iio_dev_attr_filter_low_pass_3db_frequency_available.dev_attr.attr, + &iio_dev_attr_bridge_switch_en.dev_attr.attr, + NULL +}; + +static const struct attribute_group ad7195_attribute_group = { + .attrs = ad7195_attributes, +}; + +static unsigned int ad7192_get_temp_scale(bool unipolar) +{ + return unipolar ? 2815 * 2 : 2815; +} + +static int ad7192_set_3db_filter_freq(struct ad7192_state *st, + int val, int val2) +{ + int freq_avail[4], i, ret, freq; + unsigned int diff_new, diff_old; + int idx = 0; + + diff_old = U32_MAX; + freq = val * 1000 + val2; + + ad7192_get_available_filter_freq(st, freq_avail); + + for (i = 0; i < ARRAY_SIZE(freq_avail); i++) { + diff_new = abs(freq - freq_avail[i]); + if (diff_new < diff_old) { + diff_old = diff_new; + idx = i; + } + } + + switch (idx) { + case 0: + st->f_order = AD7192_SYNC4_FILTER; + st->mode &= ~AD7192_MODE_SINC3; + + st->conf |= AD7192_CONF_CHOP; + break; + case 1: + st->f_order = AD7192_SYNC3_FILTER; + st->mode |= AD7192_MODE_SINC3; + + st->conf |= AD7192_CONF_CHOP; + break; + case 2: + st->f_order = AD7192_NO_SYNC_FILTER; + st->mode &= ~AD7192_MODE_SINC3; + + st->conf &= ~AD7192_CONF_CHOP; + break; + case 3: + st->f_order = AD7192_NO_SYNC_FILTER; + st->mode |= AD7192_MODE_SINC3; + + st->conf &= ~AD7192_CONF_CHOP; + break; + } + + ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode); + if (ret < 0) + return ret; + + return ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf); +} + +static int ad7192_get_3db_filter_freq(struct ad7192_state *st) +{ + unsigned int fadc; + + fadc = DIV_ROUND_CLOSEST(st->fclk, + st->f_order * AD7192_MODE_RATE(st->mode)); + + if (st->conf & AD7192_CONF_CHOP) + return DIV_ROUND_CLOSEST(fadc * 240, 1024); + if (st->mode & AD7192_MODE_SINC3) + return DIV_ROUND_CLOSEST(fadc * 272, 1024); + else + return DIV_ROUND_CLOSEST(fadc * 230, 1024); +} + +static int ad7192_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, + int *val2, + long m) +{ + struct ad7192_state *st = iio_priv(indio_dev); + bool unipolar = !!(st->conf & AD7192_CONF_UNIPOLAR); + + switch (m) { + case IIO_CHAN_INFO_RAW: + return ad_sigma_delta_single_conversion(indio_dev, chan, val); + case IIO_CHAN_INFO_SCALE: + switch (chan->type) { + case IIO_VOLTAGE: + mutex_lock(&st->lock); + *val = st->scale_avail[AD7192_CONF_GAIN(st->conf)][0]; + *val2 = st->scale_avail[AD7192_CONF_GAIN(st->conf)][1]; + mutex_unlock(&st->lock); + return IIO_VAL_INT_PLUS_NANO; + case IIO_TEMP: + *val = 0; + *val2 = 1000000000 / ad7192_get_temp_scale(unipolar); + return IIO_VAL_INT_PLUS_NANO; + default: + return -EINVAL; + } + case IIO_CHAN_INFO_OFFSET: + if (!unipolar) + *val = -(1 << (chan->scan_type.realbits - 1)); + else + *val = 0; + /* Kelvin to Celsius */ + if (chan->type == IIO_TEMP) + *val -= 273 * ad7192_get_temp_scale(unipolar); + return IIO_VAL_INT; + case IIO_CHAN_INFO_SAMP_FREQ: + *val = st->fclk / + (st->f_order * 1024 * AD7192_MODE_RATE(st->mode)); + return IIO_VAL_INT; + case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: + *val = ad7192_get_3db_filter_freq(st); + *val2 = 1000; + return IIO_VAL_FRACTIONAL; + } + + return -EINVAL; +} + +static int ad7192_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, + int val2, + long mask) +{ + struct ad7192_state *st = iio_priv(indio_dev); + int ret, i, div; + unsigned int tmp; + + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) + return ret; + + switch (mask) { + case IIO_CHAN_INFO_SCALE: + ret = -EINVAL; + mutex_lock(&st->lock); + for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++) + if (val2 == st->scale_avail[i][1]) { + ret = 0; + tmp = st->conf; + st->conf &= ~AD7192_CONF_GAIN(-1); + st->conf |= AD7192_CONF_GAIN(i); + if (tmp == st->conf) + break; + ad_sd_write_reg(&st->sd, AD7192_REG_CONF, + 3, st->conf); + ad7192_calibrate_all(st); + break; + } + mutex_unlock(&st->lock); + break; + case IIO_CHAN_INFO_SAMP_FREQ: + if (!val) { + ret = -EINVAL; + break; + } + + div = st->fclk / (val * st->f_order * 1024); + if (div < 1 || div > 1023) { + ret = -EINVAL; + break; + } + + st->mode &= ~AD7192_MODE_RATE(-1); + st->mode |= AD7192_MODE_RATE(div); + ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode); + break; + case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: + ret = ad7192_set_3db_filter_freq(st, val, val2 / 1000); + break; + default: + ret = -EINVAL; + } + + iio_device_release_direct_mode(indio_dev); + + return ret; +} + +static int ad7192_write_raw_get_fmt(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + long mask) +{ + switch (mask) { + case IIO_CHAN_INFO_SCALE: + return IIO_VAL_INT_PLUS_NANO; + case IIO_CHAN_INFO_SAMP_FREQ: + return IIO_VAL_INT; + case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: + return IIO_VAL_INT_PLUS_MICRO; + default: + return -EINVAL; + } +} + +static int ad7192_read_avail(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int **vals, int *type, int *length, + long mask) +{ + struct ad7192_state *st = iio_priv(indio_dev); + + switch (mask) { + case IIO_CHAN_INFO_SCALE: + *vals = (int *)st->scale_avail; + *type = IIO_VAL_INT_PLUS_NANO; + /* Values are stored in a 2D matrix */ + *length = ARRAY_SIZE(st->scale_avail) * 2; + + return IIO_AVAIL_LIST; + } + + return -EINVAL; +} + +static const struct iio_info ad7192_info = { + .read_raw = ad7192_read_raw, + .write_raw = ad7192_write_raw, + .write_raw_get_fmt = ad7192_write_raw_get_fmt, + .read_avail = ad7192_read_avail, + .attrs = &ad7192_attribute_group, + .validate_trigger = ad_sd_validate_trigger, +}; + +static const struct iio_info ad7195_info = { + .read_raw = ad7192_read_raw, + .write_raw = ad7192_write_raw, + .write_raw_get_fmt = ad7192_write_raw_get_fmt, + .read_avail = ad7192_read_avail, + .attrs = &ad7195_attribute_group, + .validate_trigger = ad_sd_validate_trigger, +}; + +#define __AD719x_CHANNEL(_si, _channel1, _channel2, _address, _extend_name, \ + _type, _mask_type_av, _ext_info) \ + { \ + .type = (_type), \ + .differential = ((_channel2) == -1 ? 0 : 1), \ + .indexed = 1, \ + .channel = (_channel1), \ + .channel2 = (_channel2), \ + .address = (_address), \ + .extend_name = (_extend_name), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ + BIT(IIO_CHAN_INFO_OFFSET), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \ + BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY), \ + .info_mask_shared_by_type_available = (_mask_type_av), \ + .ext_info = (_ext_info), \ + .scan_index = (_si), \ + .scan_type = { \ + .sign = 'u', \ + .realbits = 24, \ + .storagebits = 32, \ + .endianness = IIO_BE, \ + }, \ + } + +#define AD719x_DIFF_CHANNEL(_si, _channel1, _channel2, _address) \ + __AD719x_CHANNEL(_si, _channel1, _channel2, _address, NULL, \ + IIO_VOLTAGE, BIT(IIO_CHAN_INFO_SCALE), \ + ad7192_calibsys_ext_info) + +#define AD719x_CHANNEL(_si, _channel1, _address) \ + __AD719x_CHANNEL(_si, _channel1, -1, _address, NULL, IIO_VOLTAGE, \ + BIT(IIO_CHAN_INFO_SCALE), ad7192_calibsys_ext_info) + +#define AD719x_SHORTED_CHANNEL(_si, _channel1, _address) \ + __AD719x_CHANNEL(_si, _channel1, -1, _address, "shorted", IIO_VOLTAGE, \ + BIT(IIO_CHAN_INFO_SCALE), ad7192_calibsys_ext_info) + +#define AD719x_TEMP_CHANNEL(_si, _address) \ + __AD719x_CHANNEL(_si, 0, -1, _address, NULL, IIO_TEMP, 0, NULL) + +static const struct iio_chan_spec ad7192_channels[] = { + AD719x_DIFF_CHANNEL(0, 1, 2, AD7192_CH_AIN1P_AIN2M), + AD719x_DIFF_CHANNEL(1, 3, 4, AD7192_CH_AIN3P_AIN4M), + AD719x_TEMP_CHANNEL(2, AD7192_CH_TEMP), + AD719x_SHORTED_CHANNEL(3, 2, AD7192_CH_AIN2P_AIN2M), + AD719x_CHANNEL(4, 1, AD7192_CH_AIN1), + AD719x_CHANNEL(5, 2, AD7192_CH_AIN2), + AD719x_CHANNEL(6, 3, AD7192_CH_AIN3), + AD719x_CHANNEL(7, 4, AD7192_CH_AIN4), + IIO_CHAN_SOFT_TIMESTAMP(8), +}; + +static const struct iio_chan_spec ad7193_channels[] = { + AD719x_DIFF_CHANNEL(0, 1, 2, AD7193_CH_AIN1P_AIN2M), + AD719x_DIFF_CHANNEL(1, 3, 4, AD7193_CH_AIN3P_AIN4M), + AD719x_DIFF_CHANNEL(2, 5, 6, AD7193_CH_AIN5P_AIN6M), + AD719x_DIFF_CHANNEL(3, 7, 8, AD7193_CH_AIN7P_AIN8M), + AD719x_TEMP_CHANNEL(4, AD7193_CH_TEMP), + AD719x_SHORTED_CHANNEL(5, 2, AD7193_CH_AIN2P_AIN2M), + AD719x_CHANNEL(6, 1, AD7193_CH_AIN1), + AD719x_CHANNEL(7, 2, AD7193_CH_AIN2), + AD719x_CHANNEL(8, 3, AD7193_CH_AIN3), + AD719x_CHANNEL(9, 4, AD7193_CH_AIN4), + AD719x_CHANNEL(10, 5, AD7193_CH_AIN5), + AD719x_CHANNEL(11, 6, AD7193_CH_AIN6), + AD719x_CHANNEL(12, 7, AD7193_CH_AIN7), + AD719x_CHANNEL(13, 8, AD7193_CH_AIN8), + IIO_CHAN_SOFT_TIMESTAMP(14), +}; + +static int ad7192_channels_config(struct iio_dev *indio_dev) +{ + struct ad7192_state *st = iio_priv(indio_dev); + + switch (st->devid) { + case ID_AD7193: + indio_dev->channels = ad7193_channels; + indio_dev->num_channels = ARRAY_SIZE(ad7193_channels); + break; + default: + indio_dev->channels = ad7192_channels; + indio_dev->num_channels = ARRAY_SIZE(ad7192_channels); + break; + } + + return 0; +} + +static const struct of_device_id ad7192_of_match[] = { + { .compatible = "adi,ad7190", .data = (void *)ID_AD7190 }, + { .compatible = "adi,ad7192", .data = (void *)ID_AD7192 }, + { .compatible = "adi,ad7193", .data = (void *)ID_AD7193 }, + { .compatible = "adi,ad7195", .data = (void *)ID_AD7195 }, + {} +}; +MODULE_DEVICE_TABLE(of, ad7192_of_match); + +static int ad7192_probe(struct spi_device *spi) +{ + struct ad7192_state *st; + struct iio_dev *indio_dev; + int ret, voltage_uv = 0; + + if (!spi->irq) { + dev_err(&spi->dev, "no IRQ?\n"); + return -ENODEV; + } + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + + mutex_init(&st->lock); + + st->avdd = devm_regulator_get(&spi->dev, "avdd"); + if (IS_ERR(st->avdd)) + return PTR_ERR(st->avdd); + + ret = regulator_enable(st->avdd); + if (ret) { + dev_err(&spi->dev, "Failed to enable specified AVdd supply\n"); + return ret; + } + + st->dvdd = devm_regulator_get(&spi->dev, "dvdd"); + if (IS_ERR(st->dvdd)) { + ret = PTR_ERR(st->dvdd); + goto error_disable_avdd; + } + + ret = regulator_enable(st->dvdd); + if (ret) { + dev_err(&spi->dev, "Failed to enable specified DVdd supply\n"); + goto error_disable_avdd; + } + + voltage_uv = regulator_get_voltage(st->avdd); + + if (voltage_uv > 0) { + st->int_vref_mv = voltage_uv / 1000; + } else { + ret = voltage_uv; + dev_err(&spi->dev, "Device tree error, reference voltage undefined\n"); + goto error_disable_avdd; + } + + spi_set_drvdata(spi, indio_dev); + st->devid = (unsigned long)of_device_get_match_data(&spi->dev); + indio_dev->dev.parent = &spi->dev; + indio_dev->name = spi_get_device_id(spi)->name; + indio_dev->modes = INDIO_DIRECT_MODE; + + ret = ad7192_channels_config(indio_dev); + if (ret < 0) + goto error_disable_dvdd; + + if (st->devid == ID_AD7195) + indio_dev->info = &ad7195_info; + else + indio_dev->info = &ad7192_info; + + ad_sd_init(&st->sd, indio_dev, spi, &ad7192_sigma_delta_info); + + ret = ad_sd_setup_buffer_and_trigger(indio_dev); + if (ret) + goto error_disable_dvdd; + + st->fclk = AD7192_INT_FREQ_MHZ; + + st->mclk = devm_clk_get(&st->sd.spi->dev, "mclk"); + if (IS_ERR(st->mclk) && PTR_ERR(st->mclk) != -ENOENT) { + ret = PTR_ERR(st->mclk); + goto error_remove_trigger; + } + + st->clock_sel = ad7192_of_clock_select(st); + + if (st->clock_sel == AD7192_CLK_EXT_MCLK1_2 || + st->clock_sel == AD7192_CLK_EXT_MCLK2) { + ret = clk_prepare_enable(st->mclk); + if (ret < 0) + goto error_remove_trigger; + + st->fclk = clk_get_rate(st->mclk); + if (!ad7192_valid_external_frequency(st->fclk)) { + ret = -EINVAL; + dev_err(&spi->dev, + "External clock frequency out of bounds\n"); + goto error_disable_clk; + } + } + + ret = ad7192_setup(st, spi->dev.of_node); + if (ret) + goto error_disable_clk; + + ret = iio_device_register(indio_dev); + if (ret < 0) + goto error_disable_clk; + return 0; + +error_disable_clk: + clk_disable_unprepare(st->mclk); +error_remove_trigger: + ad_sd_cleanup_buffer_and_trigger(indio_dev); +error_disable_dvdd: + regulator_disable(st->dvdd); +error_disable_avdd: + regulator_disable(st->avdd); + + return ret; +} + +static int ad7192_remove(struct spi_device *spi) +{ + struct iio_dev *indio_dev = spi_get_drvdata(spi); + struct ad7192_state *st = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + clk_disable_unprepare(st->mclk); + ad_sd_cleanup_buffer_and_trigger(indio_dev); + + regulator_disable(st->dvdd); + regulator_disable(st->avdd); + + return 0; +} + +static struct spi_driver ad7192_driver = { + .driver = { + .name = "ad7192", + .of_match_table = ad7192_of_match, + }, + .probe = ad7192_probe, + .remove = ad7192_remove, +}; +module_spi_driver(ad7192_driver); + +MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>"); +MODULE_DESCRIPTION("Analog Devices AD7190, AD7192, AD7193, AD7195 ADC"); +MODULE_LICENSE("GPL v2"); |