From: Michael Hennerich <michael.hennerich@xxxxxxxxxx> ADM1177 is a Hot Swap Controller and Digital Power Monitor with Soft Start Pin. Datasheet: Link: https://www.analog.com/media/en/technical-documentation/data-sheets/ADM1177.pdf Signed-off-by: Michael Hennerich <michael.hennerich@xxxxxxxxxx> Co-developed-by: Beniamin Bia <beniamin.bia@xxxxxxxxxx> Signed-off-by: Beniamin Bia <beniamin.bia@xxxxxxxxxx> --- drivers/iio/adc/Kconfig | 12 ++ drivers/iio/adc/Makefile | 1 + drivers/iio/adc/adm1177.c | 257 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 270 insertions(+) create mode 100644 drivers/iio/adc/adm1177.c diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index 9554890a3200..4db8c6dcb595 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -228,6 +228,18 @@ config ASPEED_ADC To compile this driver as a module, choose M here: the module will be called aspeed_adc. +config ADM1177 + tristate "Analog Devices ADM1177 Digital Power Monitor driver" + depends on I2C + help + Say yes here to build support for Analog Devices: + ADM1177 Hot Swap Controller and Digital Power Monitor + with Soft Start Pin. Provides direct access + via sysfs. + + To compile this driver as a module, choose M here: the + module will be called adm1177. + config AT91_ADC tristate "Atmel AT91 ADC" depends on ARCH_AT91 diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile index 5ecc481c2967..7899d6a158f3 100644 --- a/drivers/iio/adc/Makefile +++ b/drivers/iio/adc/Makefile @@ -24,6 +24,7 @@ obj-$(CONFIG_AD7887) += ad7887.o obj-$(CONFIG_AD7949) += ad7949.o obj-$(CONFIG_AD799X) += ad799x.o obj-$(CONFIG_ASPEED_ADC) += aspeed_adc.o +obj-$(CONFIG_ADM1177) += adm1177.o obj-$(CONFIG_AT91_ADC) += at91_adc.o obj-$(CONFIG_AT91_SAMA5D2_ADC) += at91-sama5d2_adc.o obj-$(CONFIG_AXP20X_ADC) += axp20x_adc.o diff --git a/drivers/iio/adc/adm1177.c b/drivers/iio/adc/adm1177.c new file mode 100644 index 000000000000..daec34566a65 --- /dev/null +++ b/drivers/iio/adc/adm1177.c @@ -0,0 +1,257 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * ADM1177 Hot Swap Controller and Digital Power Monitor with Soft Start Pin + * + * Copyright 2015-2019 Analog Devices Inc. + */ + +#include <linux/device.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/regulator/consumer.h> +#include <linux/slab.h> +#include <linux/sysfs.h> + +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> +#include <linux/iio/events.h> + +/* Command Byte Operations */ +#define ADM1177_CMD_V_CONT BIT(0) +#define ADM1177_CMD_V_ONCE BIT(1) +#define ADM1177_CMD_I_CONT BIT(2) +#define ADM1177_CMD_I_ONCE BIT(3) +#define ADM1177_CMD_VRANGE BIT(4) +#define ADM1177_CMD_STATUS_RD BIT(6) + +/* Extended Register */ +#define ADM1177_REG_ALERT_EN 1 +#define ADM1177_REG_ALERT_TH 2 +#define ADM1177_REG_CONTROL 3 + +/* ADM1177_REG_ALERT_EN */ +#define ADM1177_EN_ADC_OC1 BIT(0) +#define ADM1177_EN_ADC_OC4 BIT(1) +#define ADM1177_EN_HS_ALERT BIT(2) +#define ADM1177_EN_OFF_ALERT BIT(3) +#define ADM1177_CLEAR BIT(4) + +/* ADM1177_REG_CONTROL */ +#define ADM1177_SWOFF BIT(0) + +#define ADM1177_BITS 12 + +/** + * struct adm1177_state - driver instance specific data + * @client pointer to i2c client + * @reg regulator info for the the power supply of the device + * @command internal control register + * @r_sense_uohm current sense resistor value + * @alert_threshold_ua current limit for shutdown + * @vrange_high internal voltage divider + */ +struct adm1177_state { + struct i2c_client *client; + struct regulator *reg; + u8 command; + u32 r_sense_uohm; + u32 alert_threshold_ua; + bool vrange_high; +}; + +static int adm1177_read(struct adm1177_state *st, u8 num, u8 *data) +{ + struct i2c_client *client = st->client; + int ret = 0; + + ret = i2c_master_recv(client, data, num); + if (ret < 0) { + dev_err(&client->dev, "I2C read error\n"); + return ret; + } + + return 0; +} + +static int adm1177_write_cmd(struct adm1177_state *st, u8 cmd) +{ + st->command = cmd; + return i2c_smbus_write_byte(st->client, cmd); +} + +static int adm1177_write_reg(struct adm1177_state *st, u8 reg, u8 val) +{ + return i2c_smbus_write_byte_data(st->client, reg, val); +} + +static int adm1177_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, + int *val2, + long mask) +{ + struct adm1177_state *st = iio_priv(indio_dev); + u8 data[3]; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + adm1177_read(st, 3, data); + switch (chan->type) { + case IIO_VOLTAGE: + *val = (data[0] << 4) | (data[2] >> 4); + return IIO_VAL_INT; + case IIO_CURRENT: + *val = (data[1] << 4) | (data[2] & 0xF); + return IIO_VAL_INT; + default: + return -EINVAL; + } + + case IIO_CHAN_INFO_SCALE: + switch (chan->type) { + case IIO_VOLTAGE: + if (st->command & ADM1177_CMD_VRANGE) + *val = 6650; + else + *val = 26350; + + *val2 = ADM1177_BITS; + return IIO_VAL_FRACTIONAL_LOG2; + case IIO_CURRENT: + *val = 105840 / st->r_sense_uohm; + + *val2 = ADM1177_BITS; + return IIO_VAL_FRACTIONAL_LOG2; + default: + return -EINVAL; + } + default: + return -EINVAL; + } +} + +static const struct iio_chan_spec adm1177_channels[] = { + { + .type = IIO_VOLTAGE, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE), + .indexed = 1, + .channel = 0, + }, + { + .type = IIO_CURRENT, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE), + .indexed = 1, + .channel = 0, + }, +}; + +static const struct iio_info adm1177_info = { + .read_raw = &adm1177_read_raw, +}; +static void adm1177_remove(void *data) +{ + struct adm1177_state *st = data; + + if (st->reg) + regulator_disable(st->reg); +} + +static int adm1177_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + int ret; + struct device_node *np; + struct adm1177_state *st; + struct iio_dev *indio_dev; + + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + i2c_set_clientdata(client, indio_dev); + st->client = client; + + np = client->dev.of_node; + + st->reg = devm_regulator_get_optional(&client->dev, "vref"); + if (IS_ERR(st->reg)) { + if (PTR_ERR(st->reg) == EPROBE_DEFER) + return -EPROBE_DEFER; + + st->reg = NULL; + } else { + ret = regulator_enable(st->reg); + if (ret) + return ret; + ret = devm_add_action_or_reset(&client->dev, adm1177_remove, + st); + if (ret) + return ret; + } + + of_property_read_u32(np, "adi,r-sense-micro-ohms", &st->r_sense_uohm); + of_property_read_u32(np, "adi,shutdown-threshold-microamp", + &st->alert_threshold_ua); + st->vrange_high = of_property_read_bool(np, + "adi,vrange-high-enable"); + if (st->alert_threshold_ua) { + unsigned int val; + + val = (st->alert_threshold_ua * st->r_sense_uohm * 0xFF); + val /= 105840000U; + if (val > 0xFF) { + dev_err(&client->dev, + "Requested shutdown current %d uA above limit\n", + st->alert_threshold_ua); + + val = 0xFF; + } + adm1177_write_reg(st, ADM1177_REG_ALERT_TH, val); + } + + adm1177_write_cmd(st, ADM1177_CMD_V_CONT | + ADM1177_CMD_I_CONT | + (st->vrange_high ? 0 : ADM1177_CMD_VRANGE)); + + indio_dev->name = id->name; + indio_dev->channels = adm1177_channels; + indio_dev->num_channels = ARRAY_SIZE(adm1177_channels); + + indio_dev->dev.parent = &client->dev; + indio_dev->info = &adm1177_info; + indio_dev->modes = INDIO_DIRECT_MODE; + + return devm_iio_device_register(&client->dev, indio_dev); +} + +static const struct i2c_device_id adm1177_ids[] = { + { "adm1177", 0 }, + {} +}; +MODULE_DEVICE_TABLE(i2c, adm1177_ids); + +static const struct of_device_id adm1177_dt_ids[] = { + { .compatible = "adi,adm1177" }, + {}, +}; +MODULE_DEVICE_TABLE(of, adm1177_dt_ids); + +static struct i2c_driver adm1177_driver = { + .driver = { + .name = "adm1177", + .of_match_table = adm1177_dt_ids, + }, + .probe = adm1177_probe, + .id_table = adm1177_ids, +}; +module_i2c_driver(adm1177_driver); + +MODULE_AUTHOR("Michael Hennerich <michael.hennerich@xxxxxxxxxx>"); +MODULE_DESCRIPTION("Analog Devices ADM1177 ADC driver"); +MODULE_LICENSE("GPL v2"); -- 2.17.1
