On Fri, Nov 8, 2024 at 1:40 AM Ramon Cristopher M. Calam
<ramoncristopher.calam@xxxxxxxxxx> wrote:
>
> Add ADI LT8722 full bridge DC/DC converter driver.
>
> Signed-off-by: Ramon Cristopher M. Calam <ramoncristopher.calam@xxxxxxxxxx>
> ---
> drivers/regulator/Kconfig | 10 +
> drivers/regulator/Makefile | 1 +
> drivers/regulator/lt8722-regulator.c | 701 +++++++++++++++++++++++++++
> 3 files changed, 712 insertions(+)
> create mode 100644 drivers/regulator/lt8722-regulator.c
>
> diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
> index 39297f7d8177..d88b050ce166 100644
> --- a/drivers/regulator/Kconfig
> +++ b/drivers/regulator/Kconfig
> @@ -550,6 +550,16 @@ config REGULATOR_LP8788
> help
> This driver supports LP8788 voltage regulator chip.
>
> +config REGULATOR_LT8722
> + tristate "LT8722 ultracompact full bridge driver with SPI"
> + depends on SPI && OF
> + help
> + This driver controls an Analog Devices LT8722 ultracompact 4A, 15V,
> + full bridge driver with SPI interface.
> +
> + Say M here if you want to include support for the regulator as a
> + module.
> +
> config REGULATOR_LTC3589
> tristate "LTC3589 8-output voltage regulator"
> depends on I2C
> diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
> index 3d5a803dce8a..8f9e5aec74d2 100644
> --- a/drivers/regulator/Makefile
> +++ b/drivers/regulator/Makefile
> @@ -67,6 +67,7 @@ obj-$(CONFIG_REGULATOR_LP87565) += lp87565-regulator.o
> obj-$(CONFIG_REGULATOR_LP8788) += lp8788-buck.o
> obj-$(CONFIG_REGULATOR_LP8788) += lp8788-ldo.o
> obj-$(CONFIG_REGULATOR_LP8755) += lp8755.o
> +obj-$(CONFIG_REGULATOR_LT8722) += lt8722-regulator.o
> obj-$(CONFIG_REGULATOR_LTC3589) += ltc3589.o
> obj-$(CONFIG_REGULATOR_LTC3676) += ltc3676.o
> obj-$(CONFIG_REGULATOR_MAX14577) += max14577-regulator.o
> diff --git a/drivers/regulator/lt8722-regulator.c b/drivers/regulator/lt8722-regulator.c
> new file mode 100644
> index 000000000000..f5d378c0b1f2
> --- /dev/null
> +++ b/drivers/regulator/lt8722-regulator.c
> @@ -0,0 +1,701 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Analog Devices LT8722 Ultracompact Full Bridge Driver with SPI driver
> + *
> + * Copyright 2024 Analog Devices Inc.
> + */
> +
> +#include <asm/unaligned.h>
> +#include <linux/bitfield.h>
> +#include <linux/bits.h>
> +#include <linux/crc8.h>
> +#include <linux/delay.h>
> +#include <linux/gpio.h>
> +#include <linux/math.h>
> +#include <linux/module.h>
> +#include <linux/regulator/driver.h>
> +#include <linux/regulator/machine.h>
> +#include <linux/regulator/of_regulator.h>
> +#include <linux/spi/spi.h>
> +#include <linux/util_macros.h>
> +
> +/* Register map */
> +#define LT8722_SPIS_COMMAND 0x00
> +#define LT8722_SPIS_STATUS 0x01
> +#define LT8722_SPIS_DAC_ILIMN 0x02
> +#define LT8722_SPIS_DAC_ILIMP 0x03
> +#define LT8722_SPIS_DAC 0x04
> +#define LT8722_SPIS_OV_CLAMP 0x05
> +#define LT8722_SPIS_UV_CLAMP 0x06
> +#define LT8722_SPIS_AMUX 0x07
> +
> +/* Register masks */
> +#define LT8722_SPIS_COMMAND_MASK GENMASK(21, 0)
> +#define LT8722_SPIS_STATUS_MASK GENMASK(10, 0)
> +#define LT8722_SPIS_DAC_ILIMN_MASK GENMASK(8, 0)
> +#define LT8722_SPIS_DAC_ILIMP_MASK GENMASK(8, 0)
> +#define LT8722_SPIS_DAC_MASK GENMASK(31, 0)
> +#define LT8722_SPIS_OV_CLAMP_MASK GENMASK(3, 0)
> +#define LT8722_SPIS_UV_CLAMP_MASK GENMASK(3, 0)
> +#define LT8722_SPIS_AMUX_MASK GENMASK(6, 0)
> +
> +/* SPIS_COMMAND register bit masks */
> +#define LT8722_EN_REQ_MASK BIT(0)
> +#define LT8722_SWEN_REQ_MASK BIT(1)
> +#define LT8722_SW_FRQ_SET_MASK GENMASK(4, 2)
> +#define LT8722_SW_FRQ_ADJ_MASK GENMASK(6, 5)
> +#define LT8722_SYS_DC_MASK GENMASK(8, 7)
> +#define LT8722_VCC_VREG_MASK BIT(9)
> +#define LT8722_SW_VC_IN_MASK GENMASK(13, 11)
> +#define LT8722_SPI_RST_MASK BIT(14)
> +#define LT8722_PWR_LIM_MASK GENMASK(18, 15)
> +
> +#define LT8722_FAULTS_MASK GENMASK(10, 5)
> +#define LT8722_UV_OV_MASK GENMASK(23, 20)
> +#define LT8722_OC_MASK BIT(5)
> +#define LT8722_TSD_MASK BIT(6)
> +
> +#define LT8722_CRC8_POLY 0x07
> +#define LT8722_CRC_INIT 0x00
> +
> +#define LT8722_READ_CMD 0xF4
> +#define LT8722_WRITE_CMD 0xF2
> +#define LT8722_RW_CMD_SIZE 8
> +#define LT8722_DATA_SIZE 4
> +#define LT8722_DATA_POS 2
> +#define LT8722_CRC_POS 6
> +#define LT8722_ACK 0xA5
> +#define LT8722_ACK_POS 7
> +
> +#define LT8722_DAC_VREF 2500000
> +#define LT8722_DAC_BITS 25
> +#define LT8722_ILIM_STEP 13280
> +#define LT8722_RAMP_STEPS 5
> +
> +#define LT8722_MIN_DAC_CODE 0xFF000000
> +#define LT8722_MAX_DAC_CODE 0x00FFFFFF
> +#define LT8722_ILIMN_MIN_IOUT -6786000
> +#define LT8722_ILIMN_MAX_IOUT -664640
> +#define LT8722_ILIMP_MIN_IOUT 637440
> +#define LT8722_ILIMP_MAX_IOUT 6800000
> +#define LT8722_MIN_VOUT -20000000
> +#define LT8722_MAX_VOUT 20000000
> +#define LT8722_MIN_IOUT -6786000
> +#define LT8722_MAX_IOUT 6800000
> +
> +DECLARE_CRC8_TABLE(lt8722_crc8_table);
> +
> +struct lt8722_chip_info {
> + struct spi_device *spi;
> + struct regulator_dev *rdev;
> + struct gpio_desc *en_gpio;
> + struct gpio_desc *swen_gpio;
> + int uv_clamp_uV;
> + int ov_clamp_uV;
> + int ilimn_uA;
> + int ilimp_uA;
> + int switch_freq_hz;
> + const char *switch_freq_adjust;
> + const char *duty_cycle_range;
> + int vcc_vreg_mV;
> + int peak_inductor_current_mA;
> + int power_limit_mW;
> +};
> +
> +static const unsigned int lt8722_uv_clamp[] = {
> + -20000000,
> + -18750000,
> + -17500000,
> + -16250000,
> + -15000000,
> + -13750000,
> + -12500000,
> + -11250000,
> + -10000000,
> + -8750000,
> + -7500000,
> + -6250000,
> + -5000000,
> + -3750000,
> + -2500000,
> + -1250000,
> +};
> +
> +static const unsigned int lt8722_ov_clamp[] = {
> + 1250000,
> + 2500000,
> + 3750000,
> + 5000000,
> + 6250000,
> + 7500000,
> + 8750000,
> + 10000000,
> + 11250000,
> + 12500000,
> + 13750000,
> + 15000000,
> + 16250000,
> + 17500000,
> + 18750000,
> + 20000000,
> +};
> +
> +static const unsigned int lt8722_switch_freq[] = {
> + 500000,
> + 1000000,
> + 1500000,
> + 2000000,
> + 2500000,
> + 3000000,
> +};
> +
> +static const char * const lt8722_switch_freq_adjust[] = {
> + "0%",
> + "15%",
> + "-15%",
> +};
> +
> +static const char * const lt8722_duty_cycle_range[] = {
> + "20%-80%",
> + "15%-85%",
> + "10%-90%",
> +};
> +
> +static const unsigned int lt8722_vcc_vreg[] = {
> + 3100,
> + 3400,
> +};
> +
> +static const unsigned int lt8722_peak_inductor_current[] = {
> + 252,
> + 594,
> + 936,
> + 1278,
> + 1620,
> + 1962,
> + 2304,
> + 2646,
> +};
> +
> +static const unsigned int lt8722_power_limit[] = {
> + 2000,
> + 0,
> + 3000,
> + 3500,
> +};
> +
> +static s32 _lt8722_dac_to_uV(u32 dac_val)
> +{
> + s64 tmp;
> +
> + tmp = (s64)dac_val * LT8722_DAC_VREF;
> + tmp = 16 * div_s64(tmp, BIT(LT8722_DAC_BITS));
> +
> + return tmp;
> +}
> +
> +static s32 _lt8722_uV_to_dac(s32 uV)
> +{
> + s64 tmp;
> +
> + tmp = (s64)uV * BIT(LT8722_DAC_BITS);
> + tmp = div_s64(tmp, LT8722_DAC_VREF * 16);
> +
> + return tmp;
> +}
> +
> +static int lt8722_reg_read(struct spi_device *spi, u8 reg, u32 *val)
> +{
> + int ret;
> + struct spi_transfer t;
> + u8 rx_buf[LT8722_RW_CMD_SIZE] = {0};
> + u8 tx_buf[LT8722_RW_CMD_SIZE] = {0};
> +
> + tx_buf[0] = LT8722_READ_CMD;
> + tx_buf[1] = reg << 1;
> + tx_buf[2] = crc8(lt8722_crc8_table, tx_buf, 2, LT8722_CRC_INIT);
> +
> + t.tx_buf = tx_buf;
> + t.rx_buf = rx_buf;
> + t.len = LT8722_RW_CMD_SIZE;
> +
> + ret = spi_sync_transfer(spi, &t, 1);
> + if (ret < 0)
> + return ret;
> +
> + if (rx_buf[LT8722_CRC_POS] != crc8(lt8722_crc8_table, rx_buf,
> + LT8722_CRC_POS, LT8722_CRC_INIT))
> + return -EIO;
> +
> + if (rx_buf[LT8722_ACK_POS] != LT8722_ACK)
> + return -EIO;
> +
> + *val = get_unaligned_be32(&rx_buf[LT8722_DATA_POS]);
> +
> + return 0;
> +}
> +
> +static int lt8722_reg_write(struct spi_device *spi, u8 reg, u32 val)
> +{
> + int ret;
> + struct spi_transfer t;
> + u8 rx_buf[LT8722_RW_CMD_SIZE] = {0};
> + u8 tx_buf[LT8722_RW_CMD_SIZE] = {0};
> +
> + tx_buf[0] = LT8722_WRITE_CMD;
> + tx_buf[1] = reg << 1;
> +
> + put_unaligned_be32(val, &tx_buf[LT8722_DATA_POS]);
> +
> + tx_buf[LT8722_CRC_POS] = crc8(lt8722_crc8_table, tx_buf, LT8722_CRC_POS,
> + LT8722_CRC_INIT);
> +
> + t.tx_buf = tx_buf;
> + t.rx_buf = rx_buf;
> + t.len = LT8722_RW_CMD_SIZE;
> +
> + ret = spi_sync_transfer(spi, &t, 1);
> + if (ret < 0)
> + return ret;
> +
> + if (rx_buf[LT8722_ACK_POS] != LT8722_ACK)
> + return -EIO;
> +
> + return 0;
> +}
> +
> +static int lt8722_reg_write_mask(struct spi_device *spi, u8 reg, u32 mask,
> + u32 val)
> +{
> + int ret;
> + u32 reg_val;
> +
> + ret = lt8722_reg_read(spi, reg, ®_val);
> + if (ret < 0)
> + return ret;
> +
> + reg_val = (reg_val & ~mask) | (val & mask);
> +
> + return lt8722_reg_write(spi, reg, reg_val);
> +}
> +
> +static int lt8722_set_voltage(struct regulator_dev *rdev, int min_uV,
> + int max_uV, unsigned int *selector)
> +{
> + struct lt8722_chip_info *chip = rdev_get_drvdata(rdev);
> +
> + if (min_uV < LT8722_MIN_VOUT || max_uV > LT8722_MAX_VOUT)
> + return -EINVAL;
> +
> + *selector = _lt8722_uV_to_dac(min_uV);
> +
> + return lt8722_reg_write(chip->spi, LT8722_SPIS_DAC, *selector);
> +}
> +
> +static int lt8722_get_voltage(struct regulator_dev *rdev)
> +{
> + struct lt8722_chip_info *chip = rdev_get_drvdata(rdev);
> + int ret, dac_val;
> +
> + ret = lt8722_reg_read(chip->spi, LT8722_SPIS_DAC, &dac_val);
> + if (ret < 0)
> + return ret;
> +
> + dac_val = FIELD_GET(LT8722_SPIS_DAC_MASK, dac_val);
> +
> + return _lt8722_dac_to_uV(dac_val);
> +}
> +
> +static int lt8722_get_prop_index(const u32 *table, size_t table_size, u32 value)
> +{
> + int i;
> +
> + for (i = 0; i < table_size; i++)
> + if (table[i] == value)
> + break;
Nit pick: instead of break you can return the index
instead of checking again below if it is equal to
table_size, saving one check. Once you do that
then you can get rid of below if and simply return
EINVAL.
> +
> + if (i == table_size)
> + return -EINVAL;
> +
> + return i;
> +}
> +
> +static int lt8722_parse_fw(struct lt8722_chip_info *chip,
> + struct regulator_init_data *init_data)
> +{
> + int ret;
> +
> + /* Override the min_uV constraint with the minimum output voltage */
> + init_data->constraints.min_uV = LT8722_MIN_VOUT;
> +
> + ret = device_property_read_u32(&chip->spi->dev, "adi,uv-clamp-microvolt",
> + &chip->uv_clamp_uV);
> + if (!ret) {
> + ret = lt8722_get_prop_index(lt8722_uv_clamp,
> + ARRAY_SIZE(lt8722_uv_clamp), chip->uv_clamp_uV);
> + if (ret < 0)
> + return ret;
> +
> + ret = lt8722_reg_write(chip->spi, LT8722_SPIS_UV_CLAMP, ret);
> + if (ret < 0)
> + return ret;
> +
> + /* Override the min_uV constraint with the UV clamp value */
> + init_data->constraints.min_uV = chip->uv_clamp_uV;
> + }
> +
> + /* Override the max_uV constraint with the maximum output voltage */
> + init_data->constraints.max_uV = LT8722_MAX_VOUT;
> +
> + ret = device_property_read_u32(&chip->spi->dev, "adi,ov-clamp-microvolt",
> + &chip->ov_clamp_uV);
> + if (!ret) {
> + ret = lt8722_get_prop_index(lt8722_ov_clamp,
> + ARRAY_SIZE(lt8722_ov_clamp), chip->ov_clamp_uV);
> + if (ret < 0)
> + return ret;
> +
> + ret = lt8722_reg_write(chip->spi, LT8722_SPIS_OV_CLAMP, ret);
> + if (ret < 0)
> + return ret;
> +
> + /* Override the max_uV constraint with the OV clamp value */
> + init_data->constraints.max_uV = chip->ov_clamp_uV;
> + }
> +
> + /* Override the min_uA constraint with the minimum output current */
> + init_data->constraints.min_uA = LT8722_MIN_IOUT;
> +
> + ret = device_property_read_u32(&chip->spi->dev, "adi,ilimn-microamp",
> + &chip->ilimn_uA);
> + if (!ret) {
> + if (chip->ilimn_uA < LT8722_ILIMN_MIN_IOUT ||
> + chip->ilimn_uA > LT8722_ILIMN_MAX_IOUT)
> + return -EINVAL;
> +
> + ret = div_s64(chip->ilimn_uA, -LT8722_ILIM_STEP);
> +
> + ret = lt8722_reg_write(chip->spi, LT8722_SPIS_DAC_ILIMN, ret);
> + if (ret < 0)
> + return ret;
> +
> + /* Override the min_uA constraint with the ILIMN value */
> + init_data->constraints.min_uA = chip->ilimn_uA;
> + }
> +
> + /* Override the max_uA constraint with the maximum output current */
> + init_data->constraints.max_uA = LT8722_MAX_IOUT;
> +
> + ret = device_property_read_u32(&chip->spi->dev, "adi,ilimp-microamp",
> + &chip->ilimp_uA);
> + if (!ret) {
> + if (chip->ilimp_uA < LT8722_ILIMP_MIN_IOUT ||
> + chip->ilimp_uA > LT8722_ILIMP_MAX_IOUT)
> + return -EINVAL;
> +
> + ret = div_s64(LT8722_MAX_IOUT - chip->ilimp_uA, LT8722_ILIM_STEP);
> +
> + ret = lt8722_reg_write(chip->spi, LT8722_SPIS_DAC_ILIMP, ret);
> + if (ret < 0)
> + return ret;
> +
> + /* Override the max_uA constraint with the ILIMP value */
> + init_data->constraints.max_uA = chip->ilimp_uA;
> + }
> +
> + ret = device_property_read_u32(&chip->spi->dev, "adi,switch-frequency-hz",
> + &chip->switch_freq_hz);
> + if (!ret) {
> + ret = lt8722_get_prop_index(lt8722_switch_freq,
> + ARRAY_SIZE(lt8722_switch_freq),
> + chip->switch_freq_hz);
> + if (ret < 0)
> + return ret;
> +
> + ret = lt8722_reg_write_mask(chip->spi, LT8722_SPIS_COMMAND,
> + LT8722_SW_FRQ_SET_MASK,
> + FIELD_PREP(LT8722_SW_FRQ_SET_MASK, ret));
> + if (ret < 0)
> + return ret;
> + }
> +
> + ret = device_property_match_property_string(&chip->spi->dev,
> + "adi,switch-frequency-adjust",
> + lt8722_switch_freq_adjust,
> + ARRAY_SIZE(lt8722_switch_freq_adjust));
> + if (ret >= 0) {
> + ret = lt8722_reg_write_mask(chip->spi, LT8722_SPIS_COMMAND,
> + LT8722_SW_FRQ_ADJ_MASK,
> + FIELD_PREP(LT8722_SW_FRQ_ADJ_MASK, ret));
> + if (ret < 0)
> + return ret;
> + }
> +
> + ret = device_property_match_property_string(&chip->spi->dev,
> + "adi,duty-cycle-range", lt8722_duty_cycle_range,
> + ARRAY_SIZE(lt8722_duty_cycle_range));
> + if (ret >= 0) {
> + ret = lt8722_reg_write_mask(chip->spi, LT8722_SPIS_COMMAND,
> + LT8722_SYS_DC_MASK,
> + FIELD_PREP(LT8722_SYS_DC_MASK, ret));
> + if (ret < 0)
> + return ret;
> + }
> +
> + ret = device_property_read_u32(&chip->spi->dev, "adi,vcc-vreg-millivolt",
> + &chip->vcc_vreg_mV);
> + if (!ret) {
> + ret = lt8722_get_prop_index(lt8722_vcc_vreg,
> + ARRAY_SIZE(lt8722_vcc_vreg), chip->vcc_vreg_mV);
> + if (ret < 0)
> + return ret;
> +
> + ret = lt8722_reg_write_mask(chip->spi, LT8722_SPIS_COMMAND,
> + LT8722_VCC_VREG_MASK,
> + FIELD_PREP(LT8722_VCC_VREG_MASK, ret));
> + if (ret < 0)
> + return ret;
> + }
> +
> + ret = device_property_read_u32(&chip->spi->dev,
> + "adi,peak-inductor-current-milliamp",
> + &chip->peak_inductor_current_mA);
> + if (!ret) {
> + ret = lt8722_get_prop_index(lt8722_peak_inductor_current,
> + ARRAY_SIZE(lt8722_peak_inductor_current),
> + chip->peak_inductor_current_mA);
> + if (ret < 0)
> + return ret;
> +
> + ret = lt8722_reg_write_mask(chip->spi, LT8722_SPIS_COMMAND,
> + LT8722_SW_VC_IN_MASK,
> + FIELD_PREP(LT8722_SW_VC_IN_MASK, ret));
> + if (ret < 0)
> + return ret;
> + }
> +
> + ret = device_property_read_u32(&chip->spi->dev, "adi,power-limit-milliwatt",
> + &chip->power_limit_mW);
> + if (!ret) {
> + ret = lt8722_get_prop_index(lt8722_power_limit,
> + ARRAY_SIZE(lt8722_power_limit),
> + chip->power_limit_mW);
> + if (ret < 0)
> + return ret;
> +
> + ret = lt8722_reg_write_mask(chip->spi, LT8722_SPIS_COMMAND,
> + LT8722_PWR_LIM_MASK,
> + FIELD_PREP(LT8722_PWR_LIM_MASK, ret));
> + if (ret < 0)
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int lt8722_enable(struct regulator_dev *rdev)
> +{
> + struct lt8722_chip_info *chip = rdev_get_drvdata(rdev);
> +
> + gpiod_set_value_cansleep(chip->en_gpio, 1);
> +
> + return lt8722_reg_write_mask(chip->spi, LT8722_SPIS_COMMAND,
> + LT8722_EN_REQ_MASK,
> + FIELD_PREP(LT8722_EN_REQ_MASK, 0x1));
> +}
> +
> +static int lt8722_disable(struct regulator_dev *rdev)
> +{
> + struct lt8722_chip_info *chip = rdev_get_drvdata(rdev);
> +
> + gpiod_set_value_cansleep(chip->en_gpio, 0);
> +
> + return lt8722_reg_write_mask(chip->spi, LT8722_SPIS_COMMAND,
> + LT8722_EN_REQ_MASK,
> + FIELD_PREP(LT8722_EN_REQ_MASK, 0x0));
> +}
> +
> +static int lt8722_is_enabled(struct regulator_dev *rdev)
> +{
> + struct lt8722_chip_info *chip = rdev_get_drvdata(rdev);
> + int ret;
> + u32 reg_val;
> + bool en_req, en_pin;
> +
> + ret = lt8722_reg_read(chip->spi, LT8722_SPIS_COMMAND, ®_val);
> + if (ret < 0)
> + return ret;
> +
> + en_req = FIELD_GET(LT8722_EN_REQ_MASK, reg_val);
> + en_pin = gpiod_get_value(chip->en_gpio);
> +
> + return en_req && en_pin;
> +}
> +
> +static int lt8722_get_error_flags(struct regulator_dev *rdev,
> + unsigned int *flags)
> +{
> + struct lt8722_chip_info *chip = rdev_get_drvdata(rdev);
> + int ret;
> + u32 reg_val;
> +
> + ret = lt8722_reg_read(chip->spi, LT8722_SPIS_STATUS, ®_val);
> + if (ret < 0)
> + return ret;
> +
> + *flags = 0;
> +
> + if (FIELD_GET(LT8722_OC_MASK, reg_val))
> + *flags |= REGULATOR_ERROR_OVER_CURRENT;
> +
> + if (FIELD_GET(LT8722_TSD_MASK, reg_val))
> + *flags |= REGULATOR_ERROR_OVER_TEMP;
> +
> + return 0;
> +}
> +
> +static int lt8722_set_soft_start(struct regulator_dev *rdev)
> +{
> + struct lt8722_chip_info *chip = rdev_get_drvdata(rdev);
> + s32 dac_val;
> + int ret, i;
> +
> + /* Clear faults before enabled VCC LDO and other device circuitry */
> + ret = lt8722_reg_write(chip->spi, LT8722_SPIS_STATUS, 0x0);
> + if (ret < 0)
> + return ret;
> +
> + ret = lt8722_enable(rdev);
> + if (ret < 0)
> + return ret;
> +
> + /* Configure output voltage control DAC to 0xFF000000 */
> + ret = lt8722_reg_write(chip->spi, LT8722_SPIS_DAC, LT8722_MIN_DAC_CODE);
> + if (ret < 0)
> + return ret;
> +
> + /* Write all SPIS_STATUS register bits to 0 */
> + ret = lt8722_reg_write(chip->spi, LT8722_SPIS_STATUS, 0x0);
> + if (ret < 0)
> + return ret;
> +
> + fsleep(1000);
> +
> + /* Ramp the output voltage control DAC from 0xFF000000 to 0x00000000 */
> + for (i = 0; i < LT8722_RAMP_STEPS; i++) {
> + dac_val = LT8722_MIN_DAC_CODE + 0x400000 * i;
> +
> + ret = lt8722_reg_write(chip->spi, LT8722_SPIS_DAC, dac_val);
> + if (ret < 0)
> + return ret;
> +
> + fsleep(1000);
> + }
> +
> + /* Enable the PWM switching behavior */
> + gpiod_set_value_cansleep(chip->swen_gpio, 1);
> +
> + ret = lt8722_reg_write_mask(chip->spi, LT8722_SPIS_COMMAND,
> + LT8722_SWEN_REQ_MASK,
> + FIELD_PREP(LT8722_SWEN_REQ_MASK, 0x1));
> + if (ret < 0)
> + return ret;
> +
> + fsleep(160);
> +
> + return 0;
> +}
> +
> +static const struct regulator_ops lt8722_regulator_ops = {
> + .set_voltage = lt8722_set_voltage,
> + .get_voltage = lt8722_get_voltage,
> + .enable = lt8722_enable,
> + .disable = lt8722_disable,
> + .is_enabled = lt8722_is_enabled,
> + .set_soft_start = lt8722_set_soft_start,
> + .get_error_flags = lt8722_get_error_flags,
> +};
> +
> +static struct regulator_desc lt8722_regulator_desc = {
> + .name = "lt8722",
> + .ops = <8722_regulator_ops,
> + .type = REGULATOR_VOLTAGE,
> + .owner = THIS_MODULE,
> +};
> +
> +static int lt8722_probe(struct spi_device *spi)
> +{
> + struct regulator_init_data *init_data;
> + struct regulator_config config = { };
> + struct lt8722_chip_info *chip;
> + int ret;
> +
> + init_data = of_get_regulator_init_data(&spi->dev, spi->dev.of_node,
> + <8722_regulator_desc);
> + if (!init_data)
> + return -EINVAL;
> +
> + chip = devm_kzalloc(&spi->dev, sizeof(*chip), GFP_KERNEL);
> + if (!chip)
> + return -ENOMEM;
> +
> + crc8_populate_msb(lt8722_crc8_table, LT8722_CRC8_POLY);
> +
> + chip->spi = spi;
> +
> + chip->en_gpio = devm_gpiod_get(&spi->dev, "enable", GPIOD_OUT_LOW);
> + if (IS_ERR(chip->en_gpio))
> + return PTR_ERR(chip->en_gpio);
> +
> + chip->swen_gpio = devm_gpiod_get(&spi->dev, "switch-enable",
> + GPIOD_OUT_LOW);
> + if (IS_ERR(chip->swen_gpio))
> + return PTR_ERR(chip->swen_gpio);
> +
> + ret = lt8722_reg_write_mask(chip->spi, LT8722_SPIS_COMMAND,
> + LT8722_SPI_RST_MASK,
> + FIELD_PREP(LT8722_SPI_RST_MASK, 0x1));
> + if (ret < 0)
> + return ret;
> +
> + ret = lt8722_parse_fw(chip, init_data);
> + if (ret < 0)
> + return ret;
> +
> + config.dev = &spi->dev;
> + config.init_data = init_data;
> + config.driver_data = chip;
> +
> + chip->rdev = devm_regulator_register(&spi->dev, <8722_regulator_desc,
> + &config);
> + if (IS_ERR(chip->rdev))
> + return PTR_ERR(chip->rdev);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id lt8722_of_match[] = {
> + { .compatible = "adi,lt8722", },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, lt8722_of_match);
> +
> +static const struct spi_device_id lt8722_id[] = {
> + { "lt8722" },
> + { }
> +};
> +MODULE_DEVICE_TABLE(spi, lt8722_id);
> +
> +struct spi_driver lt8722_driver = {
> + .driver = {
> + .name = "lt8722",
> + .of_match_table = lt8722_of_match,
> + },
> + .probe = lt8722_probe,
> + .id_table = lt8722_id,
> +};
> +module_spi_driver(lt8722_driver);
> +
> +MODULE_AUTHOR("Ramon Cristopher Calam <ramoncristopher.calam@xxxxxxxxxx>");
> +MODULE_DESCRIPTION("LT8722 ultracompact full bridge driver with SPI driver");
> +MODULE_LICENSE("GPL");
> --
> 2.47.0
>
>
