The AD5758 is a single channel DAC with 16-bit precision which uses the SPI interface that operates at clock rates up to 50MHz. The output can be configured as voltage or current and is available on a single terminal. Datasheet: http://www.analog.com/media/en/technical-documentation/data-sheets/ad5758.pdf Signed-off-by: Stefan Popa <stefan.popa@xxxxxxxxxx> --- Changes in v5: - changed the handling choice of voltage vs current by picking between two constant structs. - returned ad5758_wait_for_task_complete() directly where possible. - fixed double spaces and removed unnecessary parentheses. - kept the includes in alphabetical order and removed asm/div64.h. - used usleep_range() instead of udelay(). - removed unnecessary casting when calling bsearch(). Changes in v4: - fixed kbuild test robot warnings. Changes in v3: - AD5758 can be both a current and voltage output DAC. The decision is made based on the DT and the channel type is set during probe. - dc-dc-mode, range-microvolt and range-microamp are required properties. - Introduced a slew-time-us property from which slew rate clock and slew rate step are calculated using a best match algorithm. - Dropped the union from ad5758_state struct. - Introduced a IIO_CHAN_INFO_OFFSET case part of ad5758_read_raw(). - Added a TODO comment which specifies that CRC is not supported. - Kept the includes in order and removed the unused ones. - Removed unused macros and shortened the lengthy ones. - Renamed AD5758_REG_WRITE to AD5758_WR_FLAG_MSK. - Added an explanation for enum ad5758_output_range. - Used bsearch() instead of ad5758_get_array_index(). - Reduced the delays. - strtobool() -> kstrtobool(). Changes in v2: - removed unnecessary parenthesis in AD5758_REG_WRITE macro. - added missing documentation fields of ad5758_state struct. - changed the type of pwr_down attribute to bool. - changed ad5758_dc_dc_ilimt[] to ad5758_dc_dc_ilim[]. - ad5758_spi_reg_write() now returns spi_write(st->spi, &st->data[0].d32, sizeof(st->data[0].d32)); - removed unnecessary new line in ad5758_calib_mem_refresh(). - changed the type of the mode parameter in ad5758_set_dc_dc_conv_mode() from unsigned int to enum ad5758_dc_dc_mode. - removed unnecessary parenthesis in ad5758_slew_rate_config(). - changed the type of the enable parameter in ad5758_fault_prot_switch_en() from unsigned char to bool. - the same as above, but for ad5758_internal_buffers_en(). - added a missing mutex_unlock() in ad5758_reg_access(). - moved the mutex_unlock() in ad5758_read_raw() and removed the unreachable return. - returned directly where it was possible in ad5758_write_raw(). - removed the channel, scan_type and scan_index fields. - in ad5758_parse_dt(), added missing "\n", and specified what the default mode actually is. - returned directly at the end of ad5758_init(). - in ad5758_probe() used device managed for registering the device and returned directly without the error message. MAINTAINERS | 7 + drivers/iio/dac/Kconfig | 10 + drivers/iio/dac/Makefile | 1 + drivers/iio/dac/ad5758.c | 897 +++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 915 insertions(+) create mode 100644 drivers/iio/dac/ad5758.c diff --git a/MAINTAINERS b/MAINTAINERS index 00e9670..12d102d 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -796,6 +796,13 @@ M: Michael Hanselmann <linux-kernel@xxxxxxxxx> S: Supported F: drivers/macintosh/ams/ +ANALOG DEVICES INC AD5758 DRIVER +M: Stefan Popa <stefan.popa@xxxxxxxxxx> +L: linux-iio@xxxxxxxxxxxxxxx +W: http://ez.analog.com/community/linux-device-drivers +S: Supported +F: drivers/iio/dac/ad5758.c + ANALOG DEVICES INC AD5686 DRIVER M: Stefan Popa <stefan.popa@xxxxxxxxxx> L: linux-pm@xxxxxxxxxxxxxxx diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig index 06e90de..80beb64 100644 --- a/drivers/iio/dac/Kconfig +++ b/drivers/iio/dac/Kconfig @@ -167,6 +167,16 @@ config AD5755 To compile this driver as a module, choose M here: the module will be called ad5755. +config AD5758 + tristate "Analog Devices AD5758 DAC driver" + depends on SPI_MASTER + help + Say yes here to build support for Analog Devices AD5758 single channel + Digital to Analog Converter. + + To compile this driver as a module, choose M here: the + module will be called ad5758. + config AD5761 tristate "Analog Devices AD5761/61R/21/21R DAC driver" depends on SPI_MASTER diff --git a/drivers/iio/dac/Makefile b/drivers/iio/dac/Makefile index 57aa230..a1b37cf 100644 --- a/drivers/iio/dac/Makefile +++ b/drivers/iio/dac/Makefile @@ -16,6 +16,7 @@ obj-$(CONFIG_AD5592R_BASE) += ad5592r-base.o obj-$(CONFIG_AD5592R) += ad5592r.o obj-$(CONFIG_AD5593R) += ad5593r.o obj-$(CONFIG_AD5755) += ad5755.o +obj-$(CONFIG_AD5755) += ad5758.o obj-$(CONFIG_AD5761) += ad5761.o obj-$(CONFIG_AD5764) += ad5764.o obj-$(CONFIG_AD5791) += ad5791.o diff --git a/drivers/iio/dac/ad5758.c b/drivers/iio/dac/ad5758.c new file mode 100644 index 0000000..bd36333 --- /dev/null +++ b/drivers/iio/dac/ad5758.c @@ -0,0 +1,897 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * AD5758 Digital to analog converters driver + * + * Copyright 2018 Analog Devices Inc. + * + * TODO: Currently CRC is not supported in this driver + */ +#include <linux/bsearch.h> +#include <linux/delay.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/property.h> +#include <linux/spi/spi.h> + +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> + +/* AD5758 registers definition */ +#define AD5758_NOP 0x00 +#define AD5758_DAC_INPUT 0x01 +#define AD5758_DAC_OUTPUT 0x02 +#define AD5758_CLEAR_CODE 0x03 +#define AD5758_USER_GAIN 0x04 +#define AD5758_USER_OFFSET 0x05 +#define AD5758_DAC_CONFIG 0x06 +#define AD5758_SW_LDAC 0x07 +#define AD5758_KEY 0x08 +#define AD5758_GP_CONFIG1 0x09 +#define AD5758_GP_CONFIG2 0x0A +#define AD5758_DCDC_CONFIG1 0x0B +#define AD5758_DCDC_CONFIG2 0x0C +#define AD5758_WDT_CONFIG 0x0F +#define AD5758_DIGITAL_DIAG_CONFIG 0x10 +#define AD5758_ADC_CONFIG 0x11 +#define AD5758_FAULT_PIN_CONFIG 0x12 +#define AD5758_TWO_STAGE_READBACK_SELECT 0x13 +#define AD5758_DIGITAL_DIAG_RESULTS 0x14 +#define AD5758_ANALOG_DIAG_RESULTS 0x15 +#define AD5758_STATUS 0x16 +#define AD5758_CHIP_ID 0x17 +#define AD5758_FREQ_MONITOR 0x18 +#define AD5758_DEVICE_ID_0 0x19 +#define AD5758_DEVICE_ID_1 0x1A +#define AD5758_DEVICE_ID_2 0x1B +#define AD5758_DEVICE_ID_3 0x1C + +/* AD5758_DAC_CONFIG */ +#define AD5758_DAC_CONFIG_RANGE_MSK GENMASK(3, 0) +#define AD5758_DAC_CONFIG_RANGE_MODE(x) (((x) & 0xF) << 0) +#define AD5758_DAC_CONFIG_INT_EN_MSK BIT(5) +#define AD5758_DAC_CONFIG_INT_EN_MODE(x) (((x) & 0x1) << 5) +#define AD5758_DAC_CONFIG_OUT_EN_MSK BIT(6) +#define AD5758_DAC_CONFIG_OUT_EN_MODE(x) (((x) & 0x1) << 6) +#define AD5758_DAC_CONFIG_SR_EN_MSK BIT(8) +#define AD5758_DAC_CONFIG_SR_EN_MODE(x) (((x) & 0x1) << 8) +#define AD5758_DAC_CONFIG_SR_CLOCK_MSK GENMASK(12, 9) +#define AD5758_DAC_CONFIG_SR_CLOCK_MODE(x) (((x) & 0xF) << 9) +#define AD5758_DAC_CONFIG_SR_STEP_MSK GENMASK(15, 13) +#define AD5758_DAC_CONFIG_SR_STEP_MODE(x) (((x) & 0x7) << 13) + +/* AD5758_KEY */ +#define AD5758_KEY_CODE_RESET_1 0x15FA +#define AD5758_KEY_CODE_RESET_2 0xAF51 +#define AD5758_KEY_CODE_SINGLE_ADC_CONV 0x1ADC +#define AD5758_KEY_CODE_RESET_WDT 0x0D06 +#define AD5758_KEY_CODE_CALIB_MEM_REFRESH 0xFCBA + +/* AD5758_DCDC_CONFIG1 */ +#define AD5758_DCDC_CONFIG1_DCDC_VPROG_MSK GENMASK(4, 0) +#define AD5758_DCDC_CONFIG1_DCDC_VPROG_MODE(x) (((x) & 0x1F) << 0) +#define AD5758_DCDC_CONFIG1_DCDC_MODE_MSK GENMASK(6, 5) +#define AD5758_DCDC_CONFIG1_DCDC_MODE_MODE(x) (((x) & 0x3) << 5) +#define AD5758_DCDC_CONFIG1_PROT_SW_EN_MSK BIT(7) +#define AD5758_DCDC_CONFIG1_PROT_SW_EN_MODE(x) (((x) & 0x1) << 7) + +/* AD5758_DCDC_CONFIG2 */ +#define AD5758_DCDC_CONFIG2_ILIMIT_MSK GENMASK(3, 1) +#define AD5758_DCDC_CONFIG2_ILIMIT_MODE(x) (((x) & 0x7) << 1) +#define AD5758_DCDC_CONFIG2_INTR_SAT_3WI_MSK BIT(11) +#define AD5758_DCDC_CONFIG2_BUSY_3WI_MSK BIT(12) + +/* AD5758_DIGITAL_DIAG_RESULTS */ +#define AD5758_CAL_MEM_UNREFRESHED_MSK BIT(15) + +#define AD5758_WR_FLAG_MSK(x) (0x80 | ((x) & 0x1F)) + +#define AD5758_FULL_SCALE_MICRO 65535000000ULL + +/** + * struct ad5758_state - driver instance specific data + * @spi: spi_device + * @lock: mutex lock + * @out_range: struct which stores the output range + * @dc_dc_mode: variable which stores the mode of operation + * @dc_dc_ilim: variable which stores the dc-to-dc converter current limit + * @slew_time: variable which stores the target slew time + * @pwr_down: variable which contains whether a channel is powered down or not + * @data: spi transfer buffers + */ + +struct ad5758_range { + int reg; + int min; + int max; +}; + +struct ad5758_state { + struct spi_device *spi; + struct mutex lock; + struct ad5758_range out_range; + unsigned int dc_dc_mode; + unsigned int dc_dc_ilim; + unsigned int slew_time; + bool pwr_down; + __be32 d32[3]; +}; + +/** + * Output ranges corresponding to bits [3:0] from DAC_CONFIG register + * 0000: 0 V to 5 V voltage range + * 0001: 0 V to 10 V voltage range + * 0010: ±5 V voltage range + * 0011: ±10 V voltage range + * 1000: 0 mA to 20 mA current range + * 1001: 0 mA to 24 mA current range + * 1010: 4 mA to 20 mA current range + * 1011: ±20 mA current range + * 1100: ±24 mA current range + * 1101: -1 mA to +22 mA current range + */ +enum ad5758_output_range { + AD5758_RANGE_0V_5V, + AD5758_RANGE_0V_10V, + AD5758_RANGE_PLUSMINUS_5V, + AD5758_RANGE_PLUSMINUS_10V, + AD5758_RANGE_0mA_20mA = 8, + AD5758_RANGE_0mA_24mA, + AD5758_RANGE_4mA_24mA, + AD5758_RANGE_PLUSMINUS_20mA, + AD5758_RANGE_PLUSMINUS_24mA, + AD5758_RANGE_MINUS_1mA_PLUS_22mA, +}; + +enum ad5758_dc_dc_mode { + AD5758_DCDC_MODE_POWER_OFF, + AD5758_DCDC_MODE_DPC_CURRENT, + AD5758_DCDC_MODE_DPC_VOLTAGE, + AD5758_DCDC_MODE_PPC_CURRENT, +}; + +static const struct ad5758_range ad5758_voltage_range[] = { + { AD5758_RANGE_0V_5V, 0, 5000000 }, + { AD5758_RANGE_0V_10V, 0, 10000000 }, + { AD5758_RANGE_PLUSMINUS_5V, -5000000, 5000000 }, + { AD5758_RANGE_PLUSMINUS_10V, -10000000, 10000000 } +}; + +static const struct ad5758_range ad5758_current_range[] = { + { AD5758_RANGE_0mA_20mA, 0, 20000}, + { AD5758_RANGE_0mA_24mA, 0, 24000 }, + { AD5758_RANGE_4mA_24mA, 4, 24000 }, + { AD5758_RANGE_PLUSMINUS_20mA, -20000, 20000 }, + { AD5758_RANGE_PLUSMINUS_24mA, -24000, 24000 }, + { AD5758_RANGE_MINUS_1mA_PLUS_22mA, -1000, 22000 }, +}; + +static const int ad5758_sr_clk[16] = { + 240000, 200000, 150000, 128000, 64000, 32000, 16000, 8000, 4000, 2000, + 1000, 512, 256, 128, 64, 16 +}; + +static const int ad5758_sr_step[8] = { + 4, 12, 64, 120, 256, 500, 1820, 2048 +}; + +static const int ad5758_dc_dc_ilim[6] = { + 150000, 200000, 250000, 300000, 350000, 400000 +}; + +static int ad5758_spi_reg_read(struct ad5758_state *st, unsigned int addr) +{ + struct spi_transfer t[] = { + { + .tx_buf = &st->d32[0], + .len = 4, + .cs_change = 1, + }, { + .tx_buf = &st->d32[1], + .rx_buf = &st->d32[2], + .len = 4, + }, + }; + int ret; + + st->d32[0] = cpu_to_be32( + (AD5758_WR_FLAG_MSK(AD5758_TWO_STAGE_READBACK_SELECT) << 24) | + (addr << 8)); + st->d32[1] = cpu_to_be32(AD5758_WR_FLAG_MSK(AD5758_NOP) << 24); + + ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t)); + if (ret < 0) + return ret; + + return (be32_to_cpu(st->d32[2]) >> 8) & 0xFFFF; +} + +static int ad5758_spi_reg_write(struct ad5758_state *st, + unsigned int addr, + unsigned int val) +{ + st->d32[0] = cpu_to_be32((AD5758_WR_FLAG_MSK(addr) << 24) | + ((val & 0xFFFF) << 8)); + + return spi_write(st->spi, &st->d32[0], sizeof(st->d32[0])); +} + +static int ad5758_spi_write_mask(struct ad5758_state *st, + unsigned int addr, + unsigned long int mask, + unsigned int val) +{ + int regval; + + regval = ad5758_spi_reg_read(st, addr); + if (regval < 0) + return regval; + + regval &= ~mask; + regval |= val; + + return ad5758_spi_reg_write(st, addr, regval); +} + +static int cmpfunc(const void *a, const void *b) +{ + return *(int *)a - *(int *)b; +} + +static int ad5758_find_closest_match(const int *array, + unsigned int size, int val) +{ + int i; + + for (i = 0; i < size; i++) { + if (val <= array[i]) + return i; + } + + return size - 1; +} + +static int ad5758_wait_for_task_complete(struct ad5758_state *st, + unsigned int reg, + unsigned int mask) +{ + unsigned int timeout; + int ret; + + timeout = 10; + do { + ret = ad5758_spi_reg_read(st, reg); + if (ret < 0) + return ret; + + if (!(ret & mask)) + return 0; + + usleep_range(100, 1000); + } while (--timeout); + + dev_err(&st->spi->dev, + "Error reading bit 0x%x in 0x%x register\n", mask, reg); + + return -EIO; +} + +static int ad5758_calib_mem_refresh(struct ad5758_state *st) +{ + int ret; + + ret = ad5758_spi_reg_write(st, AD5758_KEY, + AD5758_KEY_CODE_CALIB_MEM_REFRESH); + if (ret < 0) { + dev_err(&st->spi->dev, + "Failed to initiate a calibration memory refresh\n"); + return ret; + } + + /* Wait to allow time for the internal calibrations to complete */ + return ad5758_wait_for_task_complete(st, AD5758_DIGITAL_DIAG_RESULTS, + AD5758_CAL_MEM_UNREFRESHED_MSK); +} + +static int ad5758_soft_reset(struct ad5758_state *st) +{ + int ret; + + ret = ad5758_spi_reg_write(st, AD5758_KEY, AD5758_KEY_CODE_RESET_1); + if (ret < 0) + return ret; + + ret = ad5758_spi_reg_write(st, AD5758_KEY, AD5758_KEY_CODE_RESET_2); + + /* Perform a software reset and wait at least 100us */ + usleep_range(100, 1000); + + return ret; +} + +static int ad5758_set_dc_dc_conv_mode(struct ad5758_state *st, + enum ad5758_dc_dc_mode mode) +{ + int ret; + + ret = ad5758_spi_write_mask(st, AD5758_DCDC_CONFIG1, + AD5758_DCDC_CONFIG1_DCDC_MODE_MSK, + AD5758_DCDC_CONFIG1_DCDC_MODE_MODE(mode)); + if (ret < 0) + return ret; + + /* + * Poll the BUSY_3WI bit in the DCDC_CONFIG2 register until it is 0. + * This allows the 3-wire interface communication to complete. + */ + ret = ad5758_wait_for_task_complete(st, AD5758_DCDC_CONFIG2, + AD5758_DCDC_CONFIG2_BUSY_3WI_MSK); + if (ret < 0) + return ret; + + st->dc_dc_mode = mode; + + return ret; +} + +static int ad5758_set_dc_dc_ilim(struct ad5758_state *st, unsigned int ilim) +{ + int ret; + + ret = ad5758_spi_write_mask(st, AD5758_DCDC_CONFIG2, + AD5758_DCDC_CONFIG2_ILIMIT_MSK, + AD5758_DCDC_CONFIG2_ILIMIT_MODE(ilim)); + if (ret < 0) + return ret; + /* + * Poll the BUSY_3WI bit in the DCDC_CONFIG2 register until it is 0. + * This allows the 3-wire interface communication to complete. + */ + return ad5758_wait_for_task_complete(st, AD5758_DCDC_CONFIG2, + AD5758_DCDC_CONFIG2_BUSY_3WI_MSK); +} + +static int ad5758_slew_rate_set(struct ad5758_state *st, + unsigned int sr_clk_idx, + unsigned int sr_step_idx) +{ + unsigned int mode; + unsigned long int mask; + int ret; + + mask = AD5758_DAC_CONFIG_SR_EN_MSK | + AD5758_DAC_CONFIG_SR_CLOCK_MSK | + AD5758_DAC_CONFIG_SR_STEP_MSK; + mode = AD5758_DAC_CONFIG_SR_EN_MODE(1) | + AD5758_DAC_CONFIG_SR_STEP_MODE(sr_step_idx) | + AD5758_DAC_CONFIG_SR_CLOCK_MODE(sr_clk_idx); + + ret = ad5758_spi_write_mask(st, AD5758_DAC_CONFIG, mask, mode); + if (ret < 0) + return ret; + + /* Wait to allow time for the internal calibrations to complete */ + return ad5758_wait_for_task_complete(st, AD5758_DIGITAL_DIAG_RESULTS, + AD5758_CAL_MEM_UNREFRESHED_MSK); +} + +static int ad5758_slew_rate_config(struct ad5758_state *st) +{ + unsigned int sr_clk_idx, sr_step_idx; + int i, res; + s64 diff_new, diff_old; + u64 sr_step, calc_slew_time; + + sr_clk_idx = 0; + sr_step_idx = 0; + diff_old = S64_MAX; + /* + * The slew time can be determined by using the formula: + * Slew Time = (Full Scale Out / (Step Size x Update Clk Freq)) + * where Slew time is expressed in microseconds + * Given the desired slew time, the following algorithm determines the + * best match for the step size and the update clock frequency. + */ + for (i = 0; i < ARRAY_SIZE(ad5758_sr_clk); i++) { + /* + * Go through each valid update clock freq and determine a raw + * value for the step size by using the formula: + * Step Size = Full Scale Out / (Update Clk Freq * Slew Time) + */ + sr_step = AD5758_FULL_SCALE_MICRO; + do_div(sr_step, ad5758_sr_clk[i]); + do_div(sr_step, st->slew_time); + /* + * After a raw value for step size was determined, find the + * closest valid match + */ + res = ad5758_find_closest_match(ad5758_sr_step, + ARRAY_SIZE(ad5758_sr_step), + sr_step); + /* Calculate the slew time */ + calc_slew_time = AD5758_FULL_SCALE_MICRO; + do_div(calc_slew_time, ad5758_sr_step[res]); + do_div(calc_slew_time, ad5758_sr_clk[i]); + /* + * Determine with how many microseconds the calculated slew time + * is different from the desired slew time and store the diff + * for the next iteration + */ + diff_new = abs(st->slew_time - calc_slew_time); + if (diff_new < diff_old) { + diff_old = diff_new; + sr_clk_idx = i; + sr_step_idx = res; + } + } + + return ad5758_slew_rate_set(st, sr_clk_idx, sr_step_idx); +} + +static int ad5758_set_out_range(struct ad5758_state *st, int range) +{ + int ret; + + ret = ad5758_spi_write_mask(st, AD5758_DAC_CONFIG, + AD5758_DAC_CONFIG_RANGE_MSK, + AD5758_DAC_CONFIG_RANGE_MODE(range)); + if (ret < 0) + return ret; + + /* Wait to allow time for the internal calibrations to complete */ + return ad5758_wait_for_task_complete(st, AD5758_DIGITAL_DIAG_RESULTS, + AD5758_CAL_MEM_UNREFRESHED_MSK); +} + +static int ad5758_fault_prot_switch_en(struct ad5758_state *st, bool enable) +{ + int ret; + + ret = ad5758_spi_write_mask(st, AD5758_DCDC_CONFIG1, + AD5758_DCDC_CONFIG1_PROT_SW_EN_MSK, + AD5758_DCDC_CONFIG1_PROT_SW_EN_MODE(enable)); + if (ret < 0) + return ret; + /* + * Poll the BUSY_3WI bit in the DCDC_CONFIG2 register until it is 0. + * This allows the 3-wire interface communication to complete. + */ + return ad5758_wait_for_task_complete(st, AD5758_DCDC_CONFIG2, + AD5758_DCDC_CONFIG2_BUSY_3WI_MSK); +} + +static int ad5758_internal_buffers_en(struct ad5758_state *st, bool enable) +{ + int ret; + + ret = ad5758_spi_write_mask(st, AD5758_DAC_CONFIG, + AD5758_DAC_CONFIG_INT_EN_MSK, + AD5758_DAC_CONFIG_INT_EN_MODE(enable)); + if (ret < 0) + return ret; + + /* Wait to allow time for the internal calibrations to complete */ + return ad5758_wait_for_task_complete(st, AD5758_DIGITAL_DIAG_RESULTS, + AD5758_CAL_MEM_UNREFRESHED_MSK); +} + +static int ad5758_reg_access(struct iio_dev *indio_dev, + unsigned int reg, + unsigned int writeval, + unsigned int *readval) +{ + struct ad5758_state *st = iio_priv(indio_dev); + int ret; + + mutex_lock(&st->lock); + if (readval) { + ret = ad5758_spi_reg_read(st, reg); + if (ret < 0) { + mutex_unlock(&st->lock); + return ret; + } + + *readval = ret; + ret = 0; + } else { + ret = ad5758_spi_reg_write(st, reg, writeval); + } + mutex_unlock(&st->lock); + + return ret; +} + +static int ad5758_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long info) +{ + struct ad5758_state *st = iio_priv(indio_dev); + int max, min, ret; + + switch (info) { + case IIO_CHAN_INFO_RAW: + mutex_lock(&st->lock); + ret = ad5758_spi_reg_read(st, AD5758_DAC_INPUT); + mutex_unlock(&st->lock); + if (ret < 0) + return ret; + + *val = ret; + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + min = st->out_range.min; + max = st->out_range.max; + *val = (max - min) / 1000; + *val2 = 16; + return IIO_VAL_FRACTIONAL_LOG2; + case IIO_CHAN_INFO_OFFSET: + min = st->out_range.min; + max = st->out_range.max; + *val = ((min * (1 << 16)) / (max - min)) / 1000; + return IIO_VAL_INT; + default: + return -EINVAL; + } +} + +static int ad5758_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long info) +{ + struct ad5758_state *st = iio_priv(indio_dev); + int ret; + + switch (info) { + case IIO_CHAN_INFO_RAW: + mutex_lock(&st->lock); + ret = ad5758_spi_reg_write(st, AD5758_DAC_INPUT, val); + mutex_unlock(&st->lock); + return ret; + default: + return -EINVAL; + } +} + +static ssize_t ad5758_read_powerdown(struct iio_dev *indio_dev, + uintptr_t priv, + const struct iio_chan_spec *chan, + char *buf) +{ + struct ad5758_state *st = iio_priv(indio_dev); + + return sprintf(buf, "%d\n", st->pwr_down); +} + +static ssize_t ad5758_write_powerdown(struct iio_dev *indio_dev, + uintptr_t priv, + struct iio_chan_spec const *chan, + const char *buf, size_t len) +{ + struct ad5758_state *st = iio_priv(indio_dev); + bool pwr_down; + unsigned int dcdc_config1_mode, dc_dc_mode, dac_config_mode, val; + unsigned long int dcdc_config1_msk, dac_config_msk; + int ret; + + ret = kstrtobool(buf, &pwr_down); + if (ret) + return ret; + + mutex_lock(&st->lock); + if (pwr_down) { + dc_dc_mode = AD5758_DCDC_MODE_POWER_OFF; + val = 0; + } else { + dc_dc_mode = st->dc_dc_mode; + val = 1; + } + + dcdc_config1_mode = AD5758_DCDC_CONFIG1_DCDC_MODE_MODE(dc_dc_mode) | + AD5758_DCDC_CONFIG1_PROT_SW_EN_MODE(val); + dcdc_config1_msk = AD5758_DCDC_CONFIG1_DCDC_MODE_MSK | + AD5758_DCDC_CONFIG1_PROT_SW_EN_MSK; + + ret = ad5758_spi_write_mask(st, AD5758_DCDC_CONFIG1, + dcdc_config1_msk, + dcdc_config1_mode); + if (ret < 0) + goto err_unlock; + + dac_config_mode = AD5758_DAC_CONFIG_OUT_EN_MODE(val) | + AD5758_DAC_CONFIG_INT_EN_MODE(val); + dac_config_msk = AD5758_DAC_CONFIG_OUT_EN_MSK | + AD5758_DAC_CONFIG_INT_EN_MSK; + + ret = ad5758_spi_write_mask(st, AD5758_DAC_CONFIG, + dac_config_msk, + dac_config_mode); + if (ret < 0) + goto err_unlock; + + st->pwr_down = pwr_down; + +err_unlock: + mutex_unlock(&st->lock); + + return ret ? ret : len; +} + +static const struct iio_info ad5758_info = { + .read_raw = ad5758_read_raw, + .write_raw = ad5758_write_raw, + .debugfs_reg_access = &ad5758_reg_access, +}; + +static const struct iio_chan_spec_ext_info ad5758_ext_info[] = { + { + .name = "powerdown", + .read = ad5758_read_powerdown, + .write = ad5758_write_powerdown, + .shared = IIO_SHARED_BY_TYPE, + }, + { } +}; + +#define AD5758_DAC_CHAN(_chan_type) { \ + .type = (_chan_type), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_RAW) | \ + BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_OFFSET), \ + .indexed = 1, \ + .output = 1, \ + .ext_info = ad5758_ext_info, \ +} + +static const struct iio_chan_spec ad5758_voltage_ch[] = { + AD5758_DAC_CHAN(IIO_VOLTAGE) +}; + +static const struct iio_chan_spec ad5758_current_ch[] = { + AD5758_DAC_CHAN(IIO_CURRENT) +}; + +static bool ad5758_is_valid_mode(enum ad5758_dc_dc_mode mode) +{ + switch (mode) { + case AD5758_DCDC_MODE_DPC_CURRENT: + case AD5758_DCDC_MODE_DPC_VOLTAGE: + case AD5758_DCDC_MODE_PPC_CURRENT: + return true; + default: + return false; + } +} + +static int ad5758_crc_disable(struct ad5758_state *st) +{ + unsigned int mask; + + mask = (AD5758_WR_FLAG_MSK(AD5758_DIGITAL_DIAG_CONFIG) << 24) | 0x5C3A; + st->d32[0] = cpu_to_be32(mask); + + return spi_write(st->spi, &st->d32[0], 4); +} + +static int ad5758_find_out_range(struct ad5758_state *st, + const struct ad5758_range *range, + unsigned int size, + int min, int max) +{ + int i; + + for (i = 0; i < size; i++) { + if ((min == range[i].min) && (max == range[i].max)) { + st->out_range.reg = range[i].reg; + st->out_range.min = range[i].min; + st->out_range.max = range[i].max; + + return 0; + } + } + + return -EINVAL; +} + +static int ad5758_parse_dt(struct ad5758_state *st) +{ + unsigned int tmp, tmparray[2], size; + const struct ad5758_range *range; + int *index, ret; + + st->dc_dc_ilim = 0; + ret = device_property_read_u32(&st->spi->dev, + "adi,dc-dc-ilim-microamp", &tmp); + if (ret) { + dev_dbg(&st->spi->dev, + "Missing \"dc-dc-ilim-microamp\" property\n"); + } else { + index = bsearch(&tmp, ad5758_dc_dc_ilim, + ARRAY_SIZE(ad5758_dc_dc_ilim), + sizeof(int), cmpfunc); + if (!index) + dev_dbg(&st->spi->dev, "dc-dc-ilim out of range\n"); + else + st->dc_dc_ilim = index - ad5758_dc_dc_ilim; + } + + ret = device_property_read_u32(&st->spi->dev, "adi,dc-dc-mode", + &st->dc_dc_mode); + if (ret) { + dev_err(&st->spi->dev, "Missing \"dc-dc-mode\" property\n"); + return ret; + } + + if (!ad5758_is_valid_mode(st->dc_dc_mode)) + return -EINVAL; + + if (st->dc_dc_mode == AD5758_DCDC_MODE_DPC_VOLTAGE) { + ret = device_property_read_u32_array(&st->spi->dev, + "adi,range-microvolt", + tmparray, 2); + if (ret) { + dev_err(&st->spi->dev, + "Missing \"range-microvolt\" property\n"); + return ret; + } + range = ad5758_voltage_range; + size = ARRAY_SIZE(ad5758_voltage_range); + } else { + ret = device_property_read_u32_array(&st->spi->dev, + "adi,range-microamp", + tmparray, 2); + if (ret) { + dev_err(&st->spi->dev, + "Missing \"range-microamp\" property\n"); + return ret; + } + range = ad5758_current_range; + size = ARRAY_SIZE(ad5758_current_range); + } + + ret = ad5758_find_out_range(st, range, size, tmparray[0], tmparray[1]); + if (ret) { + dev_err(&st->spi->dev, "range invalid\n"); + return ret; + } + + ret = device_property_read_u32(&st->spi->dev, "adi,slew-time-us", &tmp); + if (ret) { + dev_dbg(&st->spi->dev, "Missing \"slew-time-us\" property\n"); + st->slew_time = 0; + } else { + st->slew_time = tmp; + } + + return 0; +} + +static int ad5758_init(struct ad5758_state *st) +{ + int regval, ret; + + /* Disable CRC checks */ + ret = ad5758_crc_disable(st); + if (ret < 0) + return ret; + + /* Perform a software reset */ + ret = ad5758_soft_reset(st); + if (ret < 0) + return ret; + + /* Disable CRC checks */ + ret = ad5758_crc_disable(st); + if (ret < 0) + return ret; + + /* Perform a calibration memory refresh */ + ret = ad5758_calib_mem_refresh(st); + if (ret < 0) + return ret; + + regval = ad5758_spi_reg_read(st, AD5758_DIGITAL_DIAG_RESULTS); + if (regval < 0) + return regval; + + /* Clear all the error flags */ + ret = ad5758_spi_reg_write(st, AD5758_DIGITAL_DIAG_RESULTS, regval); + if (ret < 0) + return ret; + + /* Set the dc-to-dc current limit */ + ret = ad5758_set_dc_dc_ilim(st, st->dc_dc_ilim); + if (ret < 0) + return ret; + + /* Configure the dc-to-dc controller mode */ + ret = ad5758_set_dc_dc_conv_mode(st, st->dc_dc_mode); + if (ret < 0) + return ret; + + /* Configure the output range */ + ret = ad5758_set_out_range(st, st->out_range.reg); + if (ret < 0) + return ret; + + /* Enable Slew Rate Control, set the slew rate clock and step */ + if (st->slew_time) { + ret = ad5758_slew_rate_config(st); + if (ret < 0) + return ret; + } + + /* Enable the VIOUT fault protection switch (FPS is closed) */ + ret = ad5758_fault_prot_switch_en(st, 1); + if (ret < 0) + return ret; + + /* Power up the DAC and internal (INT) amplifiers */ + ret = ad5758_internal_buffers_en(st, 1); + if (ret < 0) + return ret; + + /* Enable VIOUT */ + return ad5758_spi_write_mask(st, AD5758_DAC_CONFIG, + AD5758_DAC_CONFIG_OUT_EN_MSK, + AD5758_DAC_CONFIG_OUT_EN_MODE(1)); +} + +static int ad5758_probe(struct spi_device *spi) +{ + struct ad5758_state *st; + struct iio_dev *indio_dev; + int ret; + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + spi_set_drvdata(spi, indio_dev); + + st->spi = spi; + + mutex_init(&st->lock); + + indio_dev->dev.parent = &spi->dev; + indio_dev->name = spi_get_device_id(spi)->name; + indio_dev->info = &ad5758_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->num_channels = 1; + + ret = ad5758_parse_dt(st); + if (ret < 0) + return ret; + + if (st->dc_dc_mode == AD5758_DCDC_MODE_DPC_VOLTAGE) + indio_dev->channels = ad5758_voltage_ch; + else + indio_dev->channels = ad5758_current_ch; + + ret = ad5758_init(st); + if (ret < 0) { + dev_err(&spi->dev, "AD5758 init failed\n"); + return ret; + } + + return devm_iio_device_register(&st->spi->dev, indio_dev); +} + +static const struct spi_device_id ad5758_id[] = { + { "ad5758", 0 }, + {} +}; +MODULE_DEVICE_TABLE(spi, ad5758_id); + +static struct spi_driver ad5758_driver = { + .driver = { + .name = KBUILD_MODNAME, + }, + .probe = ad5758_probe, + .id_table = ad5758_id, +}; + +module_spi_driver(ad5758_driver); + +MODULE_AUTHOR("Stefan Popa <stefan.popa@xxxxxxxxxx>"); +MODULE_DESCRIPTION("Analog Devices AD5758 DAC"); +MODULE_LICENSE("GPL v2"); -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
