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Date
From
From: Stefan Popa <stefan.popa@analog.com>
To: jic23@kernel.org,
Michael.Hennerich@analog.com,
lars@metafoo.de
Cc: knaack.h@gmx.de,
pmeerw@pmeerw.net,
mchehab@kernel.org,
davem@davemloft.net,
gregkh@linuxfoundation.org,
akpm@linux-foundation.org,
linus.walleij@linaro.org,
rdunlap@infradead.org,
lukas@wunner.de,
Ismail.Kose@maximintegrated.com,
vilhelm.gray@gmail.com,
sean.nyekjaer@prevas.dk,
pombredanne@nexb.com,
linux-iio@vger.kernel.org,
linux-kernel@vger.kernel.org,
stefan.popa@analog.com
Subject: [PATCH 1/2] iio: dac: Add AD5758 support
Date: Tue, 5 Jun 2018 16:52:34 +0300
Message-Id: <1528206754-13986-1-git-send-email-stefan.popa@analog.com>
X-Mailer: git-send-email 2.7.4

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@analog.com>
---
MAINTAINERS | 7 +
drivers/iio/dac/Kconfig | 10 +
drivers/iio/dac/Makefile | 1 +
drivers/iio/dac/ad5758.c | 826 +++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 844 insertions(+)
create mode 100644 drivers/iio/dac/ad5758.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 4b65225..1993779 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -802,6 +802,13 @@ S: Supported
F: drivers/iio/dac/ad5686*
F: drivers/iio/dac/ad5696*

+ANALOG DEVICES INC AD5758 DRIVER
+M: Stefan Popa <stefan.popa@analog.com>
+L: linux-iio@vger.kernel.org
+W: http://ez.analog.com/community/linux-device-drivers
+S: Supported
+F: drivers/iio/dac/ad5758.c
+
ANALOG DEVICES INC AD9389B DRIVER
M: Hans Verkuil <hans.verkuil@cisco.com>
L: linux-media@vger.kernel.org
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..e859f2d 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-$(CONFIG_AD5758) += ad5758.o
obj-$(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..0a26b9d
--- /dev/null
+++ b/drivers/iio/dac/ad5758.c
@@ -0,0 +1,826 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * AD5758 Digital to analog converters driver
+ *
+ * Copyright 2018 Analog Devices Inc.
+ */
+
+#include <linux/fs.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/spi/spi.h>
+#include <linux/delay.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/property.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_OVRNG_EN_MSK BIT(4)
+#define AD5758_DAC_CONFIG_OVRNG_EN_MODE(x) (((x) & 0x1) << 4)
+#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_RSET_EXT_EN_MSK BIT(7)
+#define AD5758_DAC_CONFIG_RSET_EXT_EN_MODE(x) (((x) & 0x1) << 7)
+#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_FAULT_PROT_SW_EN_MSK BIT(7)
+#define AD5758_DCDC_CONFIG1_FAULT_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_ADC_CONTROL_DIAG_MSK GENMASK(5, 4)
+#define AD5758_DCDC_CONFIG2_ADC_CONTROL_DIAG_MODE(x) (((x) & 0x3) << 4)
+#define AD5758_DCDC_CONFIG2_VIOUT_PULLDOWN_EN_MSK BIT(6)
+#define AD5758_DCDC_CONFIG2_VIOUT_PULLDOWN_EN_MODE(x) (((x) & 0x1) << 6)
+#define AD5758_DCDC_CONFIG2_SHORT_DEGLITCH_MSK BIT(7)
+#define AD5758_DCDC_CONFIG2_SHORT_DEGLITCH_MODE(x) (((x) & 0x1) << 7)
+#define AD5758_DCDC_CONFIG2_READ_COMP_DIS_MSK BIT(10)
+#define AD5758_DCDC_CONFIG2_READ_COMP_DIS_MODE(x) (((x) & 0x1) << 10)
+#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_DIG_DIAG_RES_CAL_MEM_UNREFRESHED_MSK BIT(15)
+
+#define AD5758_REG_WRITE(x) ((0x80) | ((x) & 0x1F))
+
+/* x^8 + x^2 + x^1 + x^0 */
+#define AD5758_CRC8_POLY 0x07
+
+/**
+ * struct ad5758_state - driver instance specific data
+ * @spi: spi_device
+ * @dc_dc_mode: variable which stores the mode of operation
+ * @out_range: variable which stores the output range
+ * @pwr_down: variable which contains whether a channel is powered down or not
+ * @data: spi transfer buffers
+ */
+
+struct ad5758_state {
+ struct spi_device *spi;
+ struct mutex lock;
+ unsigned int dc_dc_mode;
+ unsigned int dc_dc_ilim;
+ unsigned int sr_config[3];
+ unsigned int out_range;
+ unsigned int pwr_down;
+
+ /*
+ * DMA (thus cache coherency maintenance) requires the
+ * transfer buffers to live in their own cache lines.
+ */
+
+ union {
+ __be32 d32;
+ u8 d8[4];
+ } data[3] ____cacheline_aligned;
+};
+
+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,
+};
+
+struct ad5758_range {
+ int reg;
+ int min;
+ int max;
+};
+
+static const struct ad5758_range ad5758_min_max_table[] = {
+ { AD5758_RANGE_0V_5V, 0, 5000 },
+ { AD5758_RANGE_0V_10V, 0, 10000 },
+ { AD5758_RANGE_PLUSMINUS_5V, -5000, 5000 },
+ { AD5758_RANGE_PLUSMINUS_10V, -10000, 10000 },
+ { AD5758_RANGE_0mA_20mA, 0, 20},
+ { AD5758_RANGE_0mA_24mA, 0, 24 },
+ { AD5758_RANGE_4mA_24mA, 4, 24 },
+ { AD5758_RANGE_PLUSMINUS_20mA, -20, 20 },
+ { AD5758_RANGE_PLUSMINUS_24mA, -24, 24 },
+ { AD5758_RANGE_MINUS_1mA_PLUS_22mA, -1, 22 },
+};
+
+static const int ad5758_slew_rate_clk[16] = {
+ 240000, 200000, 150000, 128000, 64000, 32000, 16000, 8000, 4000, 2000,
+ 1000, 512, 256, 128, 64, 16
+};
+
+static const int ad5758_slew_rate_step[8] = {
+ 4, 12, 64, 120, 256, 500, 1820, 2048
+};
+
+static const int ad5758_dc_dc_ilimt[6] = {
+ 150, 200, 250, 300, 350, 400
+};
+
+static int ad5758_spi_reg_read(struct ad5758_state *st, unsigned int addr)
+{
+ struct spi_transfer t[] = {
+ {
+ .tx_buf = &st->data[0].d8[0],
+ .len = 4,
+ .cs_change = 1,
+ }, {
+ .tx_buf = &st->data[1].d8[0],
+ .rx_buf = &st->data[2].d8[0],
+ .len = 4,
+ },
+ };
+ int ret;
+
+ st->data[0].d32 = cpu_to_be32(
+ (AD5758_REG_WRITE(AD5758_TWO_STAGE_READBACK_SELECT) << 24) |
+ (addr << 8));
+ st->data[1].d32 = cpu_to_be32(AD5758_REG_WRITE(AD5758_NOP) << 24);
+
+ ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));
+ if (ret < 0)
+ return ret;
+
+ return (be32_to_cpu(st->data[2].d32) >> 8) & 0xFFFF;
+}
+
+static int ad5758_spi_reg_write(struct ad5758_state *st,
+ unsigned int addr,
+ unsigned int val)
+{
+ st->data[0].d32 = cpu_to_be32((AD5758_REG_WRITE(addr) << 24) |
+ ((val & 0xFFFF) << 8));
+
+ return spi_write(st->spi, &st->data[0].d8[0], 4);
+}
+
+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 ad5758_get_array_index(const int *array, unsigned int size, int val)
+{
+ int i;
+
+ for (i = 0; i < size; i++) {
+ if (val == array[i])
+ return i;
+ }
+
+ return -EINVAL;
+}
+
+static int ad5758_wait_for_task_complete(struct ad5758_state *st,
+ unsigned int reg,
+ unsigned int mask)
+{
+ unsigned int timeout;
+ int ret;
+
+ timeout = 4;
+ do {
+ ret = ad5758_spi_reg_read(st, reg);
+ if (ret < 0)
+ return ret;
+
+ if (!(ret & mask))
+ return 0;
+
+ mdelay(1);
+ } 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_DIG_DIAG_RES_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);
+
+ mdelay(1);
+
+ return ret;
+}
+
+static int ad5758_set_dc_dc_conv_mode(struct ad5758_state *st,
+ unsigned int 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_config(struct ad5758_state *st,
+ unsigned int enable,
+ unsigned int sr_clk,
+ unsigned int sr_step)
+{
+ 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(enable) |
+ AD5758_DAC_CONFIG_SR_CLOCK_MODE(sr_clk) |
+ AD5758_DAC_CONFIG_SR_STEP_MODE(sr_step));
+
+ 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_DIG_DIAG_RES_CAL_MEM_UNREFRESHED_MSK);
+}
+
+static int ad5758_set_out_range(struct ad5758_state *st, unsigned int range)
+{
+ int ret;
+
+ ret = ad5758_spi_write_mask(st, AD5758_DAC_CONFIG,
+ AD5758_DAC_CONFIG_RANGE_MSK,
+ AD5758_DAC_CONFIG_RANGE_MODE(
+ ad5758_min_max_table[range].reg));
+ if (ret < 0)
+ return ret;
+
+ /* Wait to allow time for the internal calibrations to complete */
+ ret = ad5758_wait_for_task_complete(st, AD5758_DIGITAL_DIAG_RESULTS,
+ AD5758_DIG_DIAG_RES_CAL_MEM_UNREFRESHED_MSK);
+ if (ret < 0)
+ return ret;
+
+ st->out_range = range;
+
+ return ret;
+}
+
+static int ad5758_fault_prot_switch_en(struct ad5758_state *st,
+ unsigned char enable)
+{
+ int ret;
+
+ ret = ad5758_spi_write_mask(st, AD5758_DCDC_CONFIG1,
+ AD5758_DCDC_CONFIG1_FAULT_PROT_SW_EN_MSK,
+ AD5758_DCDC_CONFIG1_FAULT_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,
+ unsigned char 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_DIG_DIAG_RES_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 == NULL) {
+ ret = ad5758_spi_reg_write(st, reg, writeval);
+ } else {
+ ret = ad5758_spi_reg_read(st, reg);
+ if (ret < 0)
+ return ret;
+
+ *readval = ret;
+ ret = 0;
+ }
+ 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);
+ if (ret < 0) {
+ mutex_unlock(&st->lock);
+ return ret;
+ }
+
+ *val = ret;
+ mutex_unlock(&st->lock);
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ min = ad5758_min_max_table[st->out_range].min;
+ max = ad5758_min_max_table[st->out_range].max;
+ *val = max - min;
+ *val2 = chan->scan_type.realbits;
+ return IIO_VAL_FRACTIONAL_LOG2;
+ default:
+ return -EINVAL;
+ }
+
+ 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);
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}
+
+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 = strtobool(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_FAULT_PROT_SW_EN_MODE(val));
+ dcdc_config1_msk = (AD5758_DCDC_CONFIG1_DCDC_MODE_MSK |
+ AD5758_DCDC_CONFIG1_FAULT_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_SEPARATE,
+ },
+ { },
+};
+
+static const struct iio_chan_spec ad5758_channels[] = {
+ {
+ .type = IIO_VOLTAGE,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
+ .indexed = 1,
+ .output = 1,
+ .channel = 0,
+ .scan_index = 0,
+ .scan_type = {
+ .sign = 'u',
+ .realbits = 16,
+ .storagebits = 32,
+ .shift = 0,
+ .endianness = IIO_BE,
+ },
+ .ext_info = ad5758_ext_info,
+ },
+};
+
+static int ad5758_crc_disable(struct ad5758_state *st)
+{
+ st->data[0].d32 =
+ cpu_to_be32(
+ (AD5758_REG_WRITE(AD5758_DIGITAL_DIAG_CONFIG) << 24) | 0x5C3A);
+
+ return spi_write(st->spi, &st->data[0].d8[0], 4);
+}
+
+static void ad5758_parse_dt(struct ad5758_state *st)
+{
+ unsigned int i, tmp, tmparray[3];
+ int index;
+
+ st->dc_dc_ilim = 150;
+ if (!device_property_read_u32(&st->spi->dev,
+ "adi,dc-dc-ilim", &tmp)) {
+ index = ad5758_get_array_index(ad5758_dc_dc_ilimt,
+ ARRAY_SIZE(ad5758_dc_dc_ilimt), tmp);
+ if (index < 0)
+ dev_warn(&st->spi->dev,
+ "dc-dc-ilim out of range using default");
+ else
+ st->dc_dc_ilim = index;
+ } else {
+ dev_dbg(&st->spi->dev,
+ "Missing \"dc-dc-ilim\" property, using default\n");
+ }
+
+ st->dc_dc_mode = AD5758_DCDC_MODE_DPC_VOLTAGE;
+ if (device_property_read_u32(&st->spi->dev, "adi,dc-dc-mode",
+ &st->dc_dc_mode))
+ dev_dbg(&st->spi->dev,
+ "Missing \"dc-dc-mode\" property, using DPC_VOLTAGE\n");
+
+ /* 0 V to 5 V voltage range */
+ st->out_range = 0;
+ if (!device_property_read_u32(&st->spi->dev, "adi,range", &tmp)) {
+ for (i = 0; i < ARRAY_SIZE(ad5758_min_max_table); i++) {
+ if (tmp == ad5758_min_max_table[i].reg) {
+ st->out_range = i;
+ break;
+ }
+ }
+
+ if (i == ARRAY_SIZE(ad5758_min_max_table))
+ dev_warn(&st->spi->dev, "range invalid, using default");
+ } else {
+ dev_dbg(&st->spi->dev,
+ "Missing \"range\" property, using default\n");
+ }
+
+ st->sr_config[0] = 1;
+ st->sr_config[1] = 16000;
+ st->sr_config[2] = 4;
+ if (!device_property_read_u32_array(&st->spi->dev, "adi,slew",
+ tmparray, 3)) {
+ st->sr_config[0] = tmparray[0];
+
+ index = ad5758_get_array_index(ad5758_slew_rate_clk,
+ ARRAY_SIZE(ad5758_slew_rate_clk),
+ tmparray[1]);
+
+ if (index < 0)
+ dev_warn(&st->spi->dev,
+ "slew rate clock out of range, using default");
+ else
+ st->sr_config[1] = index;
+
+ index = ad5758_get_array_index(ad5758_slew_rate_step,
+ ARRAY_SIZE(ad5758_slew_rate_step),
+ tmparray[2]);
+
+ if (index < 0)
+ dev_warn(&st->spi->dev,
+ "slew rate step out of range, using default");
+ else
+ st->sr_config[2] = index;
+ } else {
+ dev_dbg(&st->spi->dev,
+ "Missing \"slew\" property, using default\n");
+ }
+}
+
+static int ad5758_init(struct ad5758_state *st)
+{
+ int regval, ret;
+
+ ad5758_parse_dt(st);
+
+ /* 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);
+ if (ret < 0)
+ return ret;
+
+ /* Enable Slew Rate Control, set the slew rate clock and step */
+ ret = ad5758_slew_rate_config(st, st->sr_config[0],
+ st->sr_config[1], st->sr_config[2]);
+ 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 */
+ ret = ad5758_spi_write_mask(st, AD5758_DAC_CONFIG,
+ AD5758_DAC_CONFIG_OUT_EN_MSK,
+ AD5758_DAC_CONFIG_OUT_EN_MODE(1));
+
+ return ret;
+}
+
+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;
+
+ 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->channels = ad5758_channels;
+ indio_dev->num_channels = ARRAY_SIZE(ad5758_channels);
+
+ mutex_init(&st->lock);
+
+ ret = ad5758_init(st);
+ if (ret < 0) {
+ dev_err(&spi->dev, "AD5758 init failed\n");
+ return ret;
+ }
+
+ ret = iio_device_register(indio_dev);
+ if (ret) {
+ dev_err(&spi->dev, "Failed to register iio device\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+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@analog.com>");
+MODULE_DESCRIPTION("Analog Devices AD5758 DAC");
+MODULE_LICENSE("GPL v2");
--
2.7.4
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  Last update: 2018-06-05 15:53    [W:0.064 / U:0.068 seconds]
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