From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Looijmans Subject: Re: [PATCH v3 3/3] hwmon: ltc2990: support all measurement modes Date: Mon, 3 Jul 2017 08:29:56 +0200 Message-ID: <341b5c67-c013-5a7c-54b5-e8c2a7c168e7@topic.nl> References: <1499056140-6064-1-git-send-email-tom.levens@cern.ch> <1499056140-6064-3-git-send-email-tom.levens@cern.ch> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 8BIT Return-path: In-Reply-To: <1499056140-6064-3-git-send-email-tom.levens-vJEk5272eHo@public.gmane.org> Content-Language: nl Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Tom Levens , Rob Herring , Mark Rutland , Jean Delvare , Guenter Roeck Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-hwmon-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: devicetree@vger.kernel.org Applied, and tested on my board, so you have my Tested-By: mike.looijmans-Oq418RWZeHk@public.gmane.org Probably the maintainers will like to see a patch header mail with a "v3" summary for what you've changed ("git send-email --cover-letter" or something similar to that) On 03-07-17 06:29, Tom Levens wrote: > Updated version of the ltc2990 driver which supports all measurement > modes (current, voltage, temperature) available in the chip. > > If devicetree is used, the mode must be specified with the property > "lltc,meas-mode". The format and possible values of the property are > described in the binding. > > If devicetree is not used, the mode of the chip will not be configured. > Unless the chip is configured by another source, only the internal > temperature and supply voltage will be measured. > > Signed-off-by: Tom Levens > --- > Documentation/hwmon/ltc2990 | 24 ++++-- > drivers/hwmon/Kconfig | 7 +- > drivers/hwmon/ltc2990.c | 196 +++++++++++++++++++++++++++++++++++++------- > 3 files changed, 185 insertions(+), 42 deletions(-) > > diff --git a/Documentation/hwmon/ltc2990 b/Documentation/hwmon/ltc2990 > index c25211e..3ed68f6 100644 > --- a/Documentation/hwmon/ltc2990 > +++ b/Documentation/hwmon/ltc2990 > @@ -8,6 +8,7 @@ Supported chips: > Datasheet: http://www.linear.com/product/ltc2990 > > Author: Mike Looijmans > + Tom Levens > > > Description > @@ -16,10 +17,8 @@ Description > LTC2990 is a Quad I2C Voltage, Current and Temperature Monitor. > The chip's inputs can measure 4 voltages, or two inputs together (1+2 and 3+4) > can be combined to measure a differential voltage, which is typically used to > -measure current through a series resistor, or a temperature. > - > -This driver currently uses the 2x differential mode only. In order to support > -other modes, the driver will need to be expanded. > +measure current through a series resistor, or a temperature with an external > +diode. > > > Usage Notes > @@ -32,12 +31,19 @@ devices explicitly. > Sysfs attributes > ---------------- > > +in0_input Voltage at Vcc pin in millivolt (range 2.5V to 5V) > +temp1_input Internal chip temperature in millidegrees Celcius > + > +A subset of the following attributes are visible, depending on the measurement > +mode of the chip. > + > +in[1-4]_input Voltage at V[1-4] pin in millivolt > +temp2_input External temperature sensor TR1 in millidegrees Celcius > +temp3_input External temperature sensor TR2 in millidegrees Celcius > +curr1_input Current in mA across V1-V2 assuming a 1mOhm sense resistor > +curr2_input Current in mA across V3-V4 assuming a 1mOhm sense resistor > + > The "curr*_input" measurements actually report the voltage drop across the > input pins in microvolts. This is equivalent to the current through a 1mOhm > sense resistor. Divide the reported value by the actual sense resistor value > in mOhm to get the actual value. > - > -in0_input Voltage at Vcc pin in millivolt (range 2.5V to 5V) > -temp1_input Internal chip temperature in millidegrees Celcius > -curr1_input Current in mA across v1-v2 assuming a 1mOhm sense resistor. > -curr2_input Current in mA across v3-v4 assuming a 1mOhm sense resistor. > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > index 5ef2814..578e5a9 100644 > --- a/drivers/hwmon/Kconfig > +++ b/drivers/hwmon/Kconfig > @@ -709,15 +709,12 @@ config SENSORS_LTC2945 > be called ltc2945. > > config SENSORS_LTC2990 > - tristate "Linear Technology LTC2990 (current monitoring mode only)" > + tristate "Linear Technology LTC2990" > depends on I2C > help > If you say yes here you get support for Linear Technology LTC2990 > I2C System Monitor. The LTC2990 supports a combination of voltage, > - current and temperature monitoring, but in addition to the Vcc supply > - voltage and chip temperature, this driver currently only supports > - reading two currents by measuring two differential voltages across > - series resistors. > + current and temperature monitoring. > > This driver can also be built as a module. If so, the module will > be called ltc2990. > diff --git a/drivers/hwmon/ltc2990.c b/drivers/hwmon/ltc2990.c > index e320d21..32f3a8d 100644 > --- a/drivers/hwmon/ltc2990.c > +++ b/drivers/hwmon/ltc2990.c > @@ -5,10 +5,6 @@ > * Author: Mike Looijmans > * > * License: GPLv2 > - * > - * This driver assumes the chip is wired as a dual current monitor, and > - * reports the voltage drop across two series resistors. It also reports > - * the chip's internal temperature and Vcc power supply voltage. > */ > > #include > @@ -18,6 +14,7 @@ > #include > #include > #include > +#include > > #define LTC2990_STATUS 0x00 > #define LTC2990_CONTROL 0x01 > @@ -29,35 +26,109 @@ > #define LTC2990_V4_MSB 0x0C > #define LTC2990_VCC_MSB 0x0E > > -#define LTC2990_CONTROL_KELVIN BIT(7) > -#define LTC2990_CONTROL_SINGLE BIT(6) > -#define LTC2990_CONTROL_MEASURE_ALL (0x3 << 3) > -#define LTC2990_CONTROL_MODE_CURRENT 0x06 > -#define LTC2990_CONTROL_MODE_VOLTAGE 0x07 > +#define LTC2990_IN0 BIT(0) > +#define LTC2990_IN1 BIT(1) > +#define LTC2990_IN2 BIT(2) > +#define LTC2990_IN3 BIT(3) > +#define LTC2990_IN4 BIT(4) > +#define LTC2990_CURR1 BIT(5) > +#define LTC2990_CURR2 BIT(6) > +#define LTC2990_TEMP1 BIT(7) > +#define LTC2990_TEMP2 BIT(8) > +#define LTC2990_TEMP3 BIT(9) > +#define LTC2990_NONE 0 > +#define LTC2990_ALL GENMASK(9, 0) > + > +#define LTC2990_MODE0_SHIFT 0 > +#define LTC2990_MODE0_MASK GENMASK(2, 0) > +#define LTC2990_MODE1_SHIFT 3 > +#define LTC2990_MODE1_MASK GENMASK(1, 0) > + > +/* Enabled measurements for mode bits 2..0 */ > +static const int ltc2990_attrs_ena_0[] = { > + LTC2990_IN1 | LTC2990_IN2 | LTC2990_TEMP3, > + LTC2990_CURR1 | LTC2990_TEMP3, > + LTC2990_CURR1 | LTC2990_IN3 | LTC2990_IN4, > + LTC2990_TEMP2 | LTC2990_IN3 | LTC2990_IN4, > + LTC2990_TEMP2 | LTC2990_CURR2, > + LTC2990_TEMP2 | LTC2990_TEMP3, > + LTC2990_CURR1 | LTC2990_CURR2, > + LTC2990_IN1 | LTC2990_IN2 | LTC2990_IN3 | LTC2990_IN4 > +}; > + > +/* Enabled measurements for mode bits 4..3 */ > +static const int ltc2990_attrs_ena_1[] = { > + LTC2990_NONE, > + LTC2990_TEMP2 | LTC2990_IN1 | LTC2990_CURR1, > + LTC2990_TEMP3 | LTC2990_IN3 | LTC2990_CURR2, > + LTC2990_ALL > +}; > + > +struct ltc2990_data { > + struct i2c_client *i2c; > + u32 mode[2]; > +}; > > /* Return the converted value from the given register in uV or mC */ > -static int ltc2990_get_value(struct i2c_client *i2c, u8 reg, int *result) > +static int ltc2990_get_value(struct i2c_client *i2c, int index, int *result) > { > int val; > + u8 reg; > + > + switch (index) { > + case LTC2990_IN0: > + reg = LTC2990_VCC_MSB; > + break; > + case LTC2990_IN1: > + case LTC2990_CURR1: > + case LTC2990_TEMP2: > + reg = LTC2990_V1_MSB; > + break; > + case LTC2990_IN2: > + reg = LTC2990_V2_MSB; > + break; > + case LTC2990_IN3: > + case LTC2990_CURR2: > + case LTC2990_TEMP3: > + reg = LTC2990_V3_MSB; > + break; > + case LTC2990_IN4: > + reg = LTC2990_V4_MSB; > + break; > + case LTC2990_TEMP1: > + reg = LTC2990_TINT_MSB; > + break; > + default: > + return -EINVAL; > + } > > val = i2c_smbus_read_word_swapped(i2c, reg); > if (unlikely(val < 0)) > return val; > > - switch (reg) { > - case LTC2990_TINT_MSB: > - /* internal temp, 0.0625 degrees/LSB, 13-bit */ > + switch (index) { > + case LTC2990_TEMP1: > + case LTC2990_TEMP2: > + case LTC2990_TEMP3: > + /* temp, 0.0625 degrees/LSB */ > *result = sign_extend32(val, 12) * 1000 / 16; > break; > - case LTC2990_V1_MSB: > - case LTC2990_V3_MSB: > - /* Vx-Vy, 19.42uV/LSB. Depends on mode. */ > + case LTC2990_CURR1: > + case LTC2990_CURR2: > + /* Vx-Vy, 19.42uV/LSB */ > *result = sign_extend32(val, 14) * 1942 / 100; > break; > - case LTC2990_VCC_MSB: > - /* Vcc, 305.18μV/LSB, 2.5V offset */ > + case LTC2990_IN0: > + /* Vcc, 305.18uV/LSB, 2.5V offset */ > *result = sign_extend32(val, 14) * 30518 / (100 * 1000) + 2500; > break; > + case LTC2990_IN1: > + case LTC2990_IN2: > + case LTC2990_IN3: > + case LTC2990_IN4: > + /* Vx, 305.18uV/LSB */ > + *result = sign_extend32(val, 14) * 30518 / (100 * 1000); > + break; > default: > return -EINVAL; /* won't happen, keep compiler happy */ > } > @@ -69,48 +140,117 @@ static ssize_t ltc2990_show_value(struct device *dev, > struct device_attribute *da, char *buf) > { > struct sensor_device_attribute *attr = to_sensor_dev_attr(da); > + struct ltc2990_data *data = dev_get_drvdata(dev); > int value; > int ret; > > - ret = ltc2990_get_value(dev_get_drvdata(dev), attr->index, &value); > + ret = ltc2990_get_value(data->i2c, attr->index, &value); > if (unlikely(ret < 0)) > return ret; > > return snprintf(buf, PAGE_SIZE, "%d\n", value); > } > > +static umode_t ltc2990_attrs_visible(struct kobject *kobj, > + struct attribute *a, int n) > +{ > + struct device *dev = container_of(kobj, struct device, kobj); > + struct ltc2990_data *data = dev_get_drvdata(dev); > + struct device_attribute *da = > + container_of(a, struct device_attribute, attr); > + struct sensor_device_attribute *attr = to_sensor_dev_attr(da); > + > + int attrs_mask = LTC2990_IN0 | LTC2990_TEMP1 | > + ltc2990_attrs_ena_0[data->mode[0]] & > + ltc2990_attrs_ena_1[data->mode[1]]; > + > + if (attr->index & attrs_mask) > + return a->mode; > + > + return 0; > +} > + > static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, ltc2990_show_value, NULL, > - LTC2990_TINT_MSB); > + LTC2990_TEMP1); > +static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, ltc2990_show_value, NULL, > + LTC2990_TEMP2); > +static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, ltc2990_show_value, NULL, > + LTC2990_TEMP3); > static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, ltc2990_show_value, NULL, > - LTC2990_V1_MSB); > + LTC2990_CURR1); > static SENSOR_DEVICE_ATTR(curr2_input, S_IRUGO, ltc2990_show_value, NULL, > - LTC2990_V3_MSB); > + LTC2990_CURR2); > static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ltc2990_show_value, NULL, > - LTC2990_VCC_MSB); > + LTC2990_IN0); > +static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, ltc2990_show_value, NULL, > + LTC2990_IN1); > +static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, ltc2990_show_value, NULL, > + LTC2990_IN2); > +static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, ltc2990_show_value, NULL, > + LTC2990_IN3); > +static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, ltc2990_show_value, NULL, > + LTC2990_IN4); > > static struct attribute *ltc2990_attrs[] = { > &sensor_dev_attr_temp1_input.dev_attr.attr, > + &sensor_dev_attr_temp2_input.dev_attr.attr, > + &sensor_dev_attr_temp3_input.dev_attr.attr, > &sensor_dev_attr_curr1_input.dev_attr.attr, > &sensor_dev_attr_curr2_input.dev_attr.attr, > &sensor_dev_attr_in0_input.dev_attr.attr, > + &sensor_dev_attr_in1_input.dev_attr.attr, > + &sensor_dev_attr_in2_input.dev_attr.attr, > + &sensor_dev_attr_in3_input.dev_attr.attr, > + &sensor_dev_attr_in4_input.dev_attr.attr, > NULL, > }; > -ATTRIBUTE_GROUPS(ltc2990); > + > +static const struct attribute_group ltc2990_group = { > + .attrs = ltc2990_attrs, > + .is_visible = ltc2990_attrs_visible, > +}; > +__ATTRIBUTE_GROUPS(ltc2990); > > static int ltc2990_i2c_probe(struct i2c_client *i2c, > const struct i2c_device_id *id) > { > int ret; > struct device *hwmon_dev; > + struct ltc2990_data *data; > + struct device_node *of_node = i2c->dev.of_node; > > if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA | > I2C_FUNC_SMBUS_WORD_DATA)) > return -ENODEV; > > - /* Setup continuous mode, current monitor */ > + data = devm_kzalloc(&i2c->dev, sizeof(struct ltc2990_data), GFP_KERNEL); > + if (unlikely(!data)) > + return -ENOMEM; > + > + data->i2c = i2c; > + > + if (of_node) { > + ret = of_property_read_u32_array(of_node, "lltc,meas-mode", > + data->mode, 2); > + if (ret < 0) > + return ret; > + > + if (data->mode[0] & ~LTC2990_MODE0_MASK || > + data->mode[1] & ~LTC2990_MODE1_MASK) > + return -EINVAL; > + } else { > + ret = i2c_smbus_read_byte_data(i2c, LTC2990_CONTROL); > + if (ret < 0) > + return ret; > + > + data->mode[0] = ret >> LTC2990_MODE0_SHIFT & LTC2990_MODE0_MASK; > + data->mode[1] = ret >> LTC2990_MODE1_SHIFT & LTC2990_MODE1_MASK; > + } > + > + /* Setup continuous mode */ > ret = i2c_smbus_write_byte_data(i2c, LTC2990_CONTROL, > - LTC2990_CONTROL_MEASURE_ALL | > - LTC2990_CONTROL_MODE_CURRENT); > + data->mode[0] << LTC2990_MODE0_SHIFT | > + data->mode[1] << LTC2990_MODE1_SHIFT); > if (ret < 0) { > dev_err(&i2c->dev, "Error: Failed to set control mode.\n"); > return ret; > @@ -124,7 +264,7 @@ static int ltc2990_i2c_probe(struct i2c_client *i2c, > > hwmon_dev = devm_hwmon_device_register_with_groups(&i2c->dev, > i2c->name, > - i2c, > + data, > ltc2990_groups); > > return PTR_ERR_OR_ZERO(hwmon_dev); > Kind regards, Mike Looijmans System Expert TOPIC Products Materiaalweg 4, NL-5681 RJ Best Postbus 440, NL-5680 AK Best Telefoon: +31 (0) 499 33 69 79 E-mail: mike.looijmans-yhtFebqMsb9it5bFGTN0CAC/G2K4zDHf@public.gmane.org Website: www.topicproducts.com Please consider the environment before printing this e-mail -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html