On Tue, 12 Nov 2019 17:35:50 +0200 Beniamin Bia <beniamin.bia@xxxxxxxxxx> wrote: > 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> Hi Beniamin, A couple immediate thoughts. 1. That cc list has some rather non obvious people on it. Unless something fairly surprising is going on, probably better to cut it back a bit. 2. Why IIO? Not entirely obvious to me. From first glance this is definitely doing hardware monitoring. If there is a reason there should be a clear statement here on why. +CC Guenter and Jean as hwmon maintainers. Whilst I'm here, a very quick review below. > --- > 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); These wrappers don't really add anything. I'd just make the i2c calls directly inline. They will be self explanatory. > +} > + > +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, > +}; blank line here. > +static void adm1177_remove(void *data) > +{ > + struct adm1177_state *st = data; > + > + if (st->reg) > + regulator_disable(st->reg); Probe and remove should be mirror images of each other. As you have a mixture of managed and non managed calls that isn't the case here. devm_add_action_or_reset will sort this out for you if used to turn off the regulator at the right point on removal. > +} > + > +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");
