On Thu, 30 May 2019 05:55:10 -0700 Guenter Roeck <linux@xxxxxxxxxxxx> wrote: > Hi, > > On Wed, May 15, 2019 at 01:58:09AM +0300, Serge Semin wrote: > > These are simple Texas Instruments ADC working over i2c-interface with > > just one differential input and with configurable 12-16 bits resolution. > > Sample rate is fixed to 128 for ads1000 and can vary from 8 to 128 for > > ads1100. Vdd value reference value must be supplied so to properly > > translate the sampled code to the real voltage. All of these configs are > > implemented in the device drivers for hwmon subsystem. The next dts > > properties should be specified to comply the device platform setup: > > - vdd-supply - voltage regulator connected to the Vdd pin of the device > > - ti,gain - programmable gain amplifier > > - ti,datarate - converter data rate > > - ti,voltage-divider - possible resistors-base external divider > > See bindings documentation file for details. > > > > Even though these devices seem more like ads1015 series, they > > in fact pretty much different. First of all ads1000/ads1100 got less > > capabilities: just one port, no configurations of digital comparator, no > > input multi-channel multiplexer, smaller PGA and data-rate ranges. > > In addition they haven't got internal voltage reference, but instead > > are created to use Vdd pin voltage. Finally the output code value is > > provided in different format. As a result it was much easier for > > development and for future support to create a separate driver. > > > > This chicp doesn't have any real hardware monitoring characteristics > (no limit registers). It seems to be better suited to be implemented > as iio driver. If it is used as hardware monitor, the iio-hwmon bridge > should work just fine. > > Jonathan, what do you think ? Sorry for slow response, was on vacation. Agreed, this looks like a standard multipurpose ADC so probably more suited to IIO. Whether you bother with a buffered /chardev interface or not given it is a fairly slow device is a separate question (can always be added later when someone wants it). Note the voltage-divider in the DT properties is something that should have a generic representation. In IIO we have drivers/iio/afe/iio-rescale.c for that, in this case using the voltage divider binding. gain and datarate are both characteristics that should be controlled from userspace rather than via a binding. Thanks, Jonathan > > Thanks, > Guenter > > > Signed-off-by: Serge Semin <fancer.lancer@xxxxxxxxx> > > --- > > MAINTAINERS | 8 + > > drivers/hwmon/Kconfig | 10 + > > drivers/hwmon/Makefile | 1 + > > drivers/hwmon/ads1000.c | 320 ++++++++++++++++++++++++++ > > include/linux/platform_data/ads1000.h | 20 ++ > > 5 files changed, 359 insertions(+) > > create mode 100644 drivers/hwmon/ads1000.c > > create mode 100644 include/linux/platform_data/ads1000.h > > > > diff --git a/MAINTAINERS b/MAINTAINERS > > index ce573aaa04df..5c3a8107ef1a 100644 > > --- a/MAINTAINERS > > +++ b/MAINTAINERS > > @@ -517,6 +517,14 @@ W: http://ez.analog.com/community/linux-device-drivers > > S: Supported > > F: drivers/video/backlight/adp8860_bl.c > > > > +ADS1000 HARDWARE MONITOR DRIVER > > +M: Serge Semin <fancer.lancer@xxxxxxxxx> > > +L: linux-hwmon@xxxxxxxxxxxxxxx > > +S: Maintained > > +F: Documentation/hwmon/ads1000.rst > > +F: drivers/hwmon/ads1000.c > > +F: include/linux/platform_data/ads1000.h > > + > > ADS1015 HARDWARE MONITOR DRIVER > > M: Dirk Eibach <eibach@xxxxxxxx> > > L: linux-hwmon@xxxxxxxxxxxxxxx > > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > > index 1915a18b537b..a1220cc48f2f 100644 > > --- a/drivers/hwmon/Kconfig > > +++ b/drivers/hwmon/Kconfig > > @@ -1569,6 +1569,16 @@ config SENSORS_ADC128D818 > > This driver can also be built as a module. If so, the module > > will be called adc128d818. > > > > +config SENSORS_ADS1000 > > + tristate "Texas Instruments ADS1000" > > + depends on I2C > > + help > > + If you say yes here you get support for Texas Instruments > > + ADS1000/ADS1100 12-16-bit single channel ADC device. > > + > > + This driver can also be built as a module. If so, the module > > + will be called ads1000. > > + > > config SENSORS_ADS1015 > > tristate "Texas Instruments ADS1015" > > depends on I2C > > diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile > > index 8db472ea04f0..2cd82f6c651e 100644 > > --- a/drivers/hwmon/Makefile > > +++ b/drivers/hwmon/Makefile > > @@ -35,6 +35,7 @@ obj-$(CONFIG_SENSORS_ADM1026) += adm1026.o > > obj-$(CONFIG_SENSORS_ADM1029) += adm1029.o > > obj-$(CONFIG_SENSORS_ADM1031) += adm1031.o > > obj-$(CONFIG_SENSORS_ADM9240) += adm9240.o > > +obj-$(CONFIG_SENSORS_ADS1000) += ads1000.o > > obj-$(CONFIG_SENSORS_ADS1015) += ads1015.o > > obj-$(CONFIG_SENSORS_ADS7828) += ads7828.o > > obj-$(CONFIG_SENSORS_ADS7871) += ads7871.o > > diff --git a/drivers/hwmon/ads1000.c b/drivers/hwmon/ads1000.c > > new file mode 100644 > > index 000000000000..a88b738f56bd > > --- /dev/null > > +++ b/drivers/hwmon/ads1000.c > > @@ -0,0 +1,320 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * Driver for ADS1000/ADS1100 12-16-bit ADC > > + * > > + * Copyright (C) 2019 T-platforms JSC (fancer.lancer@xxxxxxxxx) > > + * > > + * Based on the ads1015 driver by Dirk Eibach. > > + * > > + * Datasheet available at: http://focus.ti.com/lit/ds/symlink/ads1000.pdf > > + */ > > + > > +#include <linux/module.h> > > +#include <linux/init.h> > > +#include <linux/slab.h> > > +#include <linux/delay.h> > > +#include <linux/i2c.h> > > +#include <linux/hwmon.h> > > +#include <linux/hwmon-sysfs.h> > > +#include <linux/err.h> > > +#include <linux/mutex.h> > > +#include <linux/regulator/consumer.h> > > +#include <linux/of_device.h> > > +#include <linux/of.h> > > +#include <linux/platform_data/ads1000.h> > > + > > +/* Data rates scale table */ > > +static const unsigned int scale_table[4] = { > > + 2048, 8192, 16384, 32768 > > +}; > > + > > +/* Minimal data rates in samples per second */ > > +static const unsigned int data_rate_table[4] = { > > + 100, 25, 12, 5 > > +}; > > + > > +#define ADS1000_DEFAULT_PGA 0 > > +#define ADS1000_DEFAULT_DATA_RATE 0 > > +#define ADS1000_DEFAULT_R1_DIVIDER 0 > > +#define ADS1000_DEFAULT_R2_DIVIDER 0 > > + > > +enum ads1000_chips { > > + ads1000, > > + ads1100, > > +}; > > + > > +struct ads1000 { > > + struct device *hwmon_dev; > > + struct mutex update_lock; > > + struct i2c_client *client; > > + struct ads1000_platform_data data; > > + enum ads1000_chips id; > > +}; > > + > > +static inline int ads1000_enable_vdd(struct ads1000 *priv) > > +{ > > + return regulator_enable(priv->data.vdd); > > +} > > + > > +static inline int ads1000_get_vdd(struct ads1000 *priv) > > +{ > > + return regulator_get_voltage(priv->data.vdd); > > +} > > + > > +static int ads1000_read_adc(struct ads1000 *priv) > > +{ > > + struct i2c_client *client = priv->client; > > + unsigned int delay_ms; > > + u8 data[3] = {0}; > > + int res; > > + > > + mutex_lock(&priv->update_lock); > > + > > + delay_ms = DIV_ROUND_UP(1000, data_rate_table[priv->data.data_rate]); > > + > > + /* setup and start single conversion */ > > + data[2] |= (1 << 7) | (1 << 4); > > + data[2] |= priv->data.pga; > > + data[2] |= priv->data.data_rate << 2; > > + > > + res = i2c_master_send(client, &data[2], 1); > > + if (res < 0) > > + goto err_unlock; > > + > > + /* wait until conversion finished */ > > + msleep(delay_ms); > > + res = i2c_master_recv(client, data, 3); > > + if (res < 0) > > + goto err_unlock; > > + > > + if (data[2] & (1 << 7)) { > > + res = -EIO; > > + goto err_unlock; > > + } > > + > > + res = ((u16)data[0] << 8) | data[1]; > > + > > +err_unlock: > > + mutex_unlock(&priv->update_lock); > > + > > + return res; > > +} > > + > > +static int ads1000_reg_to_mv(struct ads1000 *priv, s16 reg) > > +{ > > + unsigned int *divider = priv->data.divider; > > + int voltage = ads1000_get_vdd(priv); > > + int gain = 1 << priv->data.pga; > > + int c = 0; > > + > > + voltage = reg*DIV_ROUND_CLOSEST(voltage, 1000); > > + gain = gain*scale_table[priv->data.data_rate]; > > + voltage = DIV_ROUND_CLOSEST(voltage, gain); > > + > > + if (divider[0] && divider[1]) { > > + c = divider[0]*voltage; > > + c = DIV_ROUND_CLOSEST(c, (int)divider[1]); > > + } > > + > > + return voltage + c; > > +} > > + > > +static ssize_t show_in(struct device *dev, struct device_attribute *da, > > + char *buf) > > +{ > > + struct ads1000 *priv = dev_get_drvdata(dev); > > + int res; > > + > > + res = ads1000_read_adc(priv); > > + if (res < 0) > > + return res; > > + > > + return sprintf(buf, "%d\n", ads1000_reg_to_mv(priv, res)); > > +} > > + > > +static SENSOR_DEVICE_ATTR(in0_input, 0444, show_in, NULL, 0); > > + > > +static struct attribute *ads1000_attrs[] = { > > + &sensor_dev_attr_in0_input.dev_attr.attr, > > + NULL > > +}; > > +ATTRIBUTE_GROUPS(ads1000); > > + > > +static struct ads1000 *ads1000_create_priv(struct i2c_client *client, > > + const struct i2c_device_id *id) > > +{ > > + struct ads1000 *priv; > > + > > + priv = devm_kzalloc(&client->dev, sizeof(struct ads1000), > > + GFP_KERNEL); > > + if (!priv) > > + return ERR_PTR(-ENOMEM); > > + > > + if (client->dev.of_node) > > + priv->id = (enum ads1000_chips) > > + of_device_get_match_data(&client->dev); > > + else > > + priv->id = id->driver_data; > > + > > + i2c_set_clientdata(client, priv); > > + priv->client = client; > > + mutex_init(&priv->update_lock); > > + > > + return priv; > > +} > > + > > +#ifdef CONFIG_OF > > +static int ads1000_get_config_of(struct ads1000 *priv) > > +{ > > + struct i2c_client *client = priv->client; > > + struct device_node *node = client->dev.of_node; > > + u32 divider[2]; > > + u32 val; > > + > > + if (!node) > > + return -EINVAL; > > + > > + if (!of_property_read_u32(node, "ti,gain", &val)) > > + priv->data.pga = val; > > + > > + if (!of_property_read_u32(node, "ti,datarate", &val)) > > + priv->data.data_rate = val; > > + > > + if (!of_property_read_u32_array(node, "ti,voltage-divider", > > + divider, 2)) { > > + priv->data.divider[0] = divider[0]; > > + priv->data.divider[1] = divider[1]; > > + } > > + > > + priv->data.vdd = devm_regulator_get(&client->dev, "vdd"); > > + if (IS_ERR(priv->data.vdd)) > > + return PTR_ERR(priv->data.vdd); > > + > > + return 0; > > +} > > +#endif > > + > > +static int ads1000_get_config(struct ads1000 *priv) > > +{ > > + struct i2c_client *client = priv->client; > > + struct ads1000_platform_data *pdata = dev_get_platdata(&client->dev); > > + > > + priv->data.pga = ADS1000_DEFAULT_PGA; > > + priv->data.data_rate = ADS1000_DEFAULT_DATA_RATE; > > + priv->data.divider[0] = ADS1000_DEFAULT_R1_DIVIDER; > > + priv->data.divider[1] = ADS1000_DEFAULT_R2_DIVIDER; > > + > > + /* prefer platform data */ > > + if (pdata) { > > + memcpy(&priv->data, pdata, sizeof(priv->data)); > > + } else { > > +#ifdef CONFIG_OF > > + int ret; > > + > > + ret = ads1000_get_config_of(priv); > > + if (ret) > > + return ret; > > +#endif > > + } > > + > > + if (!priv->data.vdd) { > > + dev_err(&client->dev, "No VDD regulator\n"); > > + return -EINVAL; > > + } > > + > > + if (priv->data.pga > 4) { > > + dev_err(&client->dev, "Invalid gain, using default\n"); > > + priv->data.pga = ADS1000_DEFAULT_PGA; > > + } > > + > > + if (priv->data.data_rate > 4) { > > + dev_err(&client->dev, "Invalid datarate, using default\n"); > > + priv->data.data_rate = ADS1000_DEFAULT_DATA_RATE; > > + } > > + > > + if (priv->id == ads1000 && priv->data.data_rate != 0) { > > + dev_warn(&client->dev, "ADC data rate can be 128SPS only\n"); > > + priv->data.data_rate = 0; > > + } > > + > > + return 0; > > +} > > + > > +static int ads1000_set_config(struct ads1000 *priv) > > +{ > > + u8 data = 0; > > + int ret; > > + > > + /* disable continuous conversion */ > > + data |= (1 << 4); > > + data |= priv->data.pga; > > + data |= priv->data.data_rate << 2; > > + > > + ret = i2c_master_send(priv->client, &data, 1); > > + > > + return ret < 0 ? ret : 0; > > +} > > + > > +static int ads1000_probe(struct i2c_client *client, > > + const struct i2c_device_id *id) > > +{ > > + struct ads1000 *priv; > > + int ret; > > + > > + priv = ads1000_create_priv(client, id); > > + if (IS_ERR(priv)) > > + return PTR_ERR(priv); > > + > > + ret = ads1000_get_config(priv); > > + if (ret) > > + return ret; > > + > > + ret = ads1000_enable_vdd(priv); > > + if (ret) > > + return ret; > > + > > + ret = ads1000_set_config(priv); > > + if (ret) > > + return ret; > > + > > + priv->hwmon_dev = devm_hwmon_device_register_with_groups(&client->dev, > > + client->name, priv, ads1000_groups); > > + if (IS_ERR(priv->hwmon_dev)) > > + return PTR_ERR(priv->hwmon_dev); > > + > > + return 0; > > +} > > + > > +static const struct i2c_device_id ads1000_id[] = { > > + { "ads1000", ads1000}, > > + { "ads1100", ads1100}, > > + { } > > +}; > > +MODULE_DEVICE_TABLE(i2c, ads1000_id); > > + > > +static const struct of_device_id ads1000_of_match[] = { > > + { > > + .compatible = "ti,ads1000", > > + .data = (void *)ads1000 > > + }, > > + { > > + .compatible = "ti,ads1100", > > + .data = (void *)ads1100 > > + }, > > + { }, > > +}; > > +MODULE_DEVICE_TABLE(of, ads1000_of_match); > > + > > +static struct i2c_driver ads1000_driver = { > > + .driver = { > > + .name = "ads1000", > > + .of_match_table = of_match_ptr(ads1000_of_match), > > + }, > > + .probe = ads1000_probe, > > + .id_table = ads1000_id, > > +}; > > +module_i2c_driver(ads1000_driver); > > + > > +MODULE_AUTHOR("Serge Semin <fancer.lancer@xxxxxxxxx>"); > > +MODULE_DESCRIPTION("ADS1000 driver"); > > +MODULE_LICENSE("GPL v2"); > > diff --git a/include/linux/platform_data/ads1000.h b/include/linux/platform_data/ads1000.h > > new file mode 100644 > > index 000000000000..979670483537 > > --- /dev/null > > +++ b/include/linux/platform_data/ads1000.h > > @@ -0,0 +1,20 @@ > > +/* SPDX-License-Identifier: GPL-2.0 */ > > +/* > > + * Platform Data for ADS1000/ADS1100 12-16-bit ADC > > + * > > + * Copyright (C) 2019 T-platforms JSC (fancer.lancer@xxxxxxxxx) > > + */ > > + > > +#ifndef LINUX_ADS1000_H > > +#define LINUX_ADS1000_H > > + > > +#include <linux/regulator/consumer.h> > > + > > +struct ads1000_platform_data { > > + unsigned int pga; > > + unsigned int data_rate; > > + struct regulator *vdd; > > + unsigned int divider[2]; > > +}; > > + > > +#endif /* LINUX_ADS1000_H */
