[PATCH] hwmon (pmbus): Add client driver for IR35221
Samuel Mendoza-Jonas
sam at mendozajonas.com
Wed Apr 26 11:03:55 AEST 2017
On Fri, 2017-04-21 at 06:49 -0700, Guenter Roeck wrote:
> On 04/20/2017 09:25 PM, Samuel Mendoza-Jonas wrote:
> > IR35221 is a Digital DC-DC Multiphase Converter
> >
> > Signed-off-by: Samuel Mendoza-Jonas <sam at mendozajonas.com>
> > ---
> > - Tested on a ppc64 system which includes several of these devices.
> > - This patch re-implements the linear reg2data/data2reg functions from
> > pmbus-core like some other drivers in order to scale some results. Is
> > this something that would be better off being made generic for pmbus
> > drivers to call?
>
> That might make sense. The only other driver is zl6100, or am I missing
> something ?
I believe ltc2978 has a small implementation as well.
>
> Trying to understand the code, the data format seems to be linear11 with
> an added exponent on top of it. Is that correct ? If so, I wonder if we should
> make that configurable, ie store the additional exponent in R and handle it
> in the pmbus core. Would that help ?
Yes that's essentially what it is. Using R for the extra exponent would
be a neat solution, however at least for this chip commands in the same
class have different scaling exponents (eg VIN_UV_WARN_LIMIT vs
READ_VIN). I'll have a look though and see if I can cover this - maybe a
small wrapper function that updates the exponent in the data returned by
pmbus_read_word_data()/etc?
>
> If so, and if you have time, feel free to provide patches the modify the
> pmbus core code accordingly.
>
> > - The resolution of iout0 is apparently configurable between two values,
> > however the documentation I have access to does not specify how this is
> > actually configured - currently it is left at the default resolution in
> > the driver.
> >
>
> Nothing we can do about that, but it might make sense to add a note somewhere
> in the driver.
>
> > Documentation/hwmon/ir35221 | 87 ++++++++++++
> > drivers/hwmon/pmbus/Kconfig | 11 ++
> > drivers/hwmon/pmbus/Makefile | 1 +
> > drivers/hwmon/pmbus/ir35221.c | 322 ++++++++++++++++++++++++++++++++++++++++++
> > 4 files changed, 421 insertions(+)
> > create mode 100644 Documentation/hwmon/ir35221
> > create mode 100644 drivers/hwmon/pmbus/ir35221.c
> >
> > diff --git a/Documentation/hwmon/ir35221 b/Documentation/hwmon/ir35221
> > new file mode 100644
> > index 000000000000..f7e112752c04
> > --- /dev/null
> > +++ b/Documentation/hwmon/ir35221
> > @@ -0,0 +1,87 @@
> > +Kernel driver ir35221
> > +=====================
> > +
> > +Supported chips:
> > + * Infinion IR35221
> > + Prefix: 'ir35221'
> > + Addresses scanned: -
> > + Datasheet: Datasheet is not publicly available.
>
> The chip doesn't even publicly exist, which is really annoying :-(.
>
> > +
> > +Author: Samuel Mendoza-Jonas <sam at mendozajonas.com>
> > +
> > +
> > +Description
> > +-----------
> > +
> > +IR35221 is a Digital DC-DC Multiphase Converter
> > +
> > +
> > +Usage Notes
> > +-----------
> > +
> > +This driver does not probe for PMBus devices. You will have to instantiate
> > +devices explicitly.
> > +
> > +Example: the following commands will load the driver for an IR35221
> > +at address 0x70 on I2C bus #4:
> > +
> > +# modprobe ir35221
> > +# echo ir35221 0x70 > /sys/bus/i2c/devices/i2c-4/new_device
> > +
> > +
> > +Sysfs attributes
> > +----------------
> > +
> > +curr1_label "iin"
> > +curr1_input Measured input current
> > +curr1_max Maximum current
> > +curr1_max_alarm Current high alarm
> > +
> > +curr[2-3]_label "iout[1-2]"
> > +curr[2-3]_input Measured output current
> > +curr[2-3]_crit Critical maximum current
> > +curr[2-3]_crit_alarm Current critical high alarm
> > +curr[2-3]_highest Highest output current
> > +curr[2-3]_lowest Lowest output current
> > +curr[2-3]_max Maximum current
> > +curr[2-3]_max_alarm Current high alarm
> > +
> > +in1_label "vin"
> > +in1_input Measured input voltage
> > +in1_crit Critical maximum input voltage
> > +in1_crit_alarm Input voltage critical high alarm
> > +in1_highest Highest input voltage
> > +in1_lowest Lowest input voltage
> > +in1_min Minimum input voltage
> > +in1_min_alarm Input voltage low alarm
> > +
> > +in[2-3]_label "vout[1-2]"
> > +in[2-3]_input Measured output voltage
> > +in[2-3]_lcrit Critical minimum output voltage
> > +in[2-3]_lcrit_alarm Output voltage critical low alarm
> > +in[2-3]_crit Critical maximum output voltage
> > +in[2-3]_crit_alarm Output voltage critical high alarm
> > +in[2-3]_highest Highest output voltage
> > +in[2-3]_lowest Lowest output voltage
> > +in[2-3]_max Maximum output voltage
> > +in[2-3]_max_alarm Output voltage high alarm
> > +in[2-3]_min Minimum output voltage
> > +in[2-3]_min_alarm Output voltage low alarm
> > +
> > +power1_label "pin"
> > +power1_input Measured input power
> > +power1_alarm Input power high alarm
> > +power1_max Input power limit
> > +
> > +power[2-3]_label "pout[1-2]"
> > +power[2-3]_input Measured output power
> > +power[2-3]_max Output power limit
> > +power[2-3]_max_alarm Output power high alarm
> > +
> > +temp[1-2]_input Measured temperature
> > +temp[1-2]_crit Critical high temperature
> > +temp[1-2]_crit_alarm Chip temperature critical high alarm
> > +temp[1-2]_highest Highest temperature
> > +temp[1-2]_lowest Lowest temperature
> > +temp[1-2]_max Maximum temperature
> > +temp[1-2]_max_alarm Chip temperature high alarm
> > diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
> > index cad1229b7e17..88c7d6b116f8 100644
> > --- a/drivers/hwmon/pmbus/Kconfig
> > +++ b/drivers/hwmon/pmbus/Kconfig
> > @@ -159,4 +159,15 @@ config SENSORS_ZL6100
> > This driver can also be built as a module. If so, the module will
> > be called zl6100.
> >
> > +config SENSORS_IR35221
> > + tristate "Infineon IR35221"
> > + default n
> > + help
> > + If you say yes here you get hardware monitoring support for the
> > + Infineon IR35221 controller.
> > +
> > + This driver can also be built as a module. If so, the module will
> > + be called ir35521.
> > +
> > +
> > endif # PMBUS
> > diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
> > index 562132054aaf..75bb7ca619d9 100644
> > --- a/drivers/hwmon/pmbus/Makefile
> > +++ b/drivers/hwmon/pmbus/Makefile
> > @@ -5,6 +5,7 @@
> > obj-$(CONFIG_PMBUS) += pmbus_core.o
> > obj-$(CONFIG_SENSORS_PMBUS) += pmbus.o
> > obj-$(CONFIG_SENSORS_ADM1275) += adm1275.o
> > +obj-$(CONFIG_SENSORS_IR35221) += ir35221.o
> > obj-$(CONFIG_SENSORS_LM25066) += lm25066.o
> > obj-$(CONFIG_SENSORS_LTC2978) += ltc2978.o
> > obj-$(CONFIG_SENSORS_LTC3815) += ltc3815.o
> > diff --git a/drivers/hwmon/pmbus/ir35221.c b/drivers/hwmon/pmbus/ir35221.c
> > new file mode 100644
> > index 000000000000..e73b1aeb0085
> > --- /dev/null
> > +++ b/drivers/hwmon/pmbus/ir35221.c
> > @@ -0,0 +1,322 @@
> > +/*
> > + * Hardware monitoring driver for IR35221
> > + *
> > + * Copyright (C) IBM Corporation 2017.
> > + *
> > + * This program is free software; you can redistribute it and/or
> > + * modify it under the terms of the GNU General Public License
> > + * as published by the Free Software Foundation; either version
> > + * 2 of the License, or (at your option) any later version.
> > + */
> > +
> > +#include <linux/kernel.h>
> > +#include <linux/module.h>
> > +#include <linux/err.h>
> > +#include <linux/init.h>
> > +#include <linux/i2c.h>
>
> Alphabetic order please.
>
> > +#include "pmbus.h"
> > +
> > +#define IR35221_IC_DEVICE_ID 0xad
> > +#define IR35221_IC_DEVICE_REV 0xae
> > +#define IR35221_USER_DATA_00 0xb0
> > +#define IR35221_USER_DATA_01 0xb1
> > +#define IR35221_MFR_READ_VAUX 0xc4
> > +#define IR35221_MFR_VIN_PEAK 0xc5
> > +#define IR35221_MFR_VOUT_PEAK 0xc6
> > +#define IR35221_MFR_IOUT_PEAK 0xc7
> > +#define IR35221_MFR_TEMP_PEAK 0xc8
> > +#define IR35221_MFR_VIN_VALLEY 0xc9
> > +#define IR35221_MFR_VOUT_VALLEY 0xca
> > +#define IR35221_MFR_IOUT_VALLEY 0xcb
> > +#define IR35221_MFR_TEMP_VALLEY 0xcc
> > +#define IR35221_VOUT_RESET 0xce
> > +#define IR35221_RESET_TRANSITION_RATE 0xcf
> > +#define IR35221_MFR_REG_ACCESS 0xd0
> > +#define IR35221_MFR_I2C_ADDRESS 0xd6
>
> I don't think those are all used. Please drop the unused definitions.
>
> > +
> > +static long ir35221_reg2data(int data, enum pmbus_sensor_classes class)
> > +{
> > + s16 exponent;
> > + s32 mantissa;
> > + long val;
> > +
> > + /* We only modify LINEAR11 formats */
> > + exponent = ((s16)data) >> 11;
> > + mantissa = ((s16)((data & 0x7ff) << 5)) >> 5;
> > +
> > + val = mantissa * 1000L;
> > +
> > + /* scale result to micro-units for power sensors */
> > + if (class == PSC_POWER)
> > + val = val * 1000L;
> > +
> > + if (exponent >= 0)
> > + val <<= exponent;
> > + else
> > + val >>= -exponent;
> > +
> > + return val;
> > +}
> > +
> > +#define MAX_MANTISSA (1023 * 1000)
> > +#define MIN_MANTISSA (511 * 1000)
> > +
> > +static u16 ir35221_data2reg(long val, enum pmbus_sensor_classes class)
> > +{
> > + s16 exponent = 0, mantissa;
> > + bool negative = false;
> > +
> > + if (val == 0)
> > + return 0;
> > +
> > + if (val < 0) {
> > + negative = true;
> > + val = -val;
> > + }
> > +
> > + /* Power is in uW. Convert to mW before converting. */
> > + if (class == PSC_POWER)
> > + val = DIV_ROUND_CLOSEST(val, 1000L);
> > +
> > + /* Reduce large mantissa until it fits into 10 bit */
> > + while (val >= MAX_MANTISSA && exponent < 15) {
> > + exponent++;
> > + val >>= 1;
> > + }
> > + /* Increase small mantissa to improve precision */
> > + while (val < MIN_MANTISSA && exponent > -15) {
> > + exponent--;
> > + val <<= 1;
> > + }
> > +
> > + /* Convert mantissa from milli-units to units */
> > + mantissa = DIV_ROUND_CLOSEST(val, 1000);
> > +
> > + /* Ensure that resulting number is within range */
> > + if (mantissa > 0x3ff)
> > + mantissa = 0x3ff;
> > +
> > + /* restore sign */
> > + if (negative)
> > + mantissa = -mantissa;
> > +
> > + /* Convert to 5 bit exponent, 11 bit mantissa */
> > + return (mantissa & 0x7ff) | ((exponent << 11) & 0xf800);
> > +}
> > +
> > +static u16 ir35221_scale_result(s16 data, int shift,
> > + enum pmbus_sensor_classes class)
> > +{
> > + long val;
> > +
> > + val = ir35221_reg2data(data, class);
> > +
> > + if (shift < 0)
> > + val >>= -shift;
> > + else
> > + val <<= shift;
> > +
> > + return ir35221_data2reg(val, class);
> > +}
> > +
> > +static int ir35221_read_word_data(struct i2c_client *client, int page, int reg)
> > +{
> > + int ret;
> > +
> > + switch (reg) {
> > + case PMBUS_IOUT_OC_FAULT_LIMIT:
> > + case PMBUS_IOUT_OC_WARN_LIMIT:
> > + ret = pmbus_read_word_data(client, page, reg);
> > + ret = ir35221_scale_result(ret, 1, PSC_CURRENT_OUT);
> > + break;
> > + case PMBUS_VIN_OV_FAULT_LIMIT:
> > + case PMBUS_VIN_OV_WARN_LIMIT:
> > + case PMBUS_VIN_UV_WARN_LIMIT:
> > + ret = pmbus_read_word_data(client, page, reg);
> > + ret = ir35221_scale_result(ret, -4, PSC_VOLTAGE_IN);
> > + break;
> > + case PMBUS_IIN_OC_WARN_LIMIT:
> > + ret = pmbus_read_word_data(client, page, reg);
> > + ret = ir35221_scale_result(ret, -1, PSC_CURRENT_IN);
> > + case PMBUS_READ_VIN:
> > + ret = pmbus_read_word_data(client, page, PMBUS_READ_VIN);
> > + ret = ir35221_scale_result(ret, -5, PSC_VOLTAGE_IN);
> > + break;
> > + case PMBUS_READ_IIN:
> > + ret = pmbus_read_word_data(client, page, PMBUS_READ_IIN);
> > + if (page == 0)
> > + ret = ir35221_scale_result(ret, -4, PSC_CURRENT_IN);
> > + else
> > + ret = ir35221_scale_result(ret, -5, PSC_CURRENT_IN);
>
> Wow, per-page exponent. Someone was inventive.
> If we move scaling to the core, this would still be simpler as the additional
> scale could be handled here.
>
> > + break;
> > + case PMBUS_READ_POUT:
> > + ret = pmbus_read_word_data(client, page, PMBUS_READ_POUT);
> > + ret = ir35221_scale_result(ret, -1, PSC_POWER);
> > + break;
> > + case PMBUS_READ_PIN:
> > + ret = pmbus_read_word_data(client, page, PMBUS_READ_PIN);
> > + ret = ir35221_scale_result(ret, -1, PSC_POWER);
> > + break;
> > + case PMBUS_READ_IOUT:
> > + ret = pmbus_read_word_data(client, page, PMBUS_READ_IOUT);
> > + if (page == 0)
> > + ret = ir35221_scale_result(ret, -1, PSC_CURRENT_OUT);
> > + else
> > + ret = ir35221_scale_result(ret, -2, PSC_CURRENT_OUT);
> > + break;
> > + case PMBUS_VIRT_READ_VIN_MAX:
> > + ret = pmbus_read_word_data(client, page, IR35221_MFR_VIN_PEAK);
> > + ret = ir35221_scale_result(ret, -5, PSC_VOLTAGE_IN);
> > + break;
> > + case PMBUS_VIRT_READ_VOUT_MAX:
> > + ret = pmbus_read_word_data(client, page, IR35221_MFR_VOUT_PEAK);
> > + break;
> > + case PMBUS_VIRT_READ_IOUT_MAX:
> > + ret = pmbus_read_word_data(client, page, IR35221_MFR_IOUT_PEAK);
> > + if (page == 0)
> > + ret = ir35221_scale_result(ret, -1, PSC_CURRENT_IN);
> > + else
> > + ret = ir35221_scale_result(ret, -2, PSC_CURRENT_IN);
> > + break;
> > + case PMBUS_VIRT_READ_TEMP_MAX:
> > + ret = pmbus_read_word_data(client, page, IR35221_MFR_TEMP_PEAK);
> > + break;
> > + case PMBUS_VIRT_READ_VIN_MIN:
> > + ret = pmbus_read_word_data(client, page,
> > + IR35221_MFR_VIN_VALLEY);
> > + ret = ir35221_scale_result(ret, -5, PSC_VOLTAGE_IN);
> > + break;
> > + case PMBUS_VIRT_READ_VOUT_MIN:
> > + ret = pmbus_read_word_data(client, page,
> > + IR35221_MFR_VOUT_VALLEY);
> > + break;
> > + case PMBUS_VIRT_READ_IOUT_MIN:
> > + ret = pmbus_read_word_data(client, page,
> > + IR35221_MFR_IOUT_VALLEY);
> > + if (page == 0)
> > + ret = ir35221_scale_result(ret, -1, PSC_CURRENT_IN);
> > + else
> > + ret = ir35221_scale_result(ret, -2, PSC_CURRENT_IN);
> > + break;
> > + case PMBUS_VIRT_READ_TEMP_MIN:
> > + ret = pmbus_read_word_data(client, page,
> > + IR35221_MFR_TEMP_VALLEY);
> > + break;
> > + default:
> > + ret = -ENODATA;
> > + break;
> > + }
> > +
> > + return ret;
> > +}
> > +
> > +static int ir35221_write_word_data(struct i2c_client *client, int page, int reg,
> > + u16 word)
> > +{
> > + int ret;
> > + u16 val;
> > +
> > + switch (reg) {
> > + case PMBUS_IOUT_OC_FAULT_LIMIT:
> > + case PMBUS_IOUT_OC_WARN_LIMIT:
> > + val = ir35221_scale_result(word, -1, PSC_CURRENT_OUT);
> > + ret = pmbus_write_word_data(client, page, reg, val);
> > + break;
> > + case PMBUS_VIN_OV_FAULT_LIMIT:
> > + case PMBUS_VIN_OV_WARN_LIMIT:
> > + case PMBUS_VIN_UV_WARN_LIMIT:
> > + val = ir35221_scale_result(word, 4, PSC_VOLTAGE_IN);
> > + ret = pmbus_write_word_data(client, page, reg, val);
> > + break;
> > + case PMBUS_IIN_OC_WARN_LIMIT:
> > + val = ir35221_scale_result(word, 1, PSC_CURRENT_IN);
> > + ret = pmbus_write_word_data(client, page, reg, val);
> > + default:
> > + ret = -ENODATA;
> > + break;
> > + }
> > +
> > + return ret;
> > +}
> > +
> > +static int ir35221_probe(struct i2c_client *client,
> > + const struct i2c_device_id *id)
> > +{
> > + struct pmbus_driver_info *info;
> > + u8 buf[I2C_SMBUS_BLOCK_MAX];
> > + int ret;
> > +
> > + if (!i2c_check_functionality(client->adapter,
> > + I2C_FUNC_SMBUS_READ_BYTE_DATA
> > + | I2C_FUNC_SMBUS_READ_WORD_DATA
> > + | I2C_FUNC_SMBUS_READ_BLOCK_DATA))
> > + return -ENODEV;
> > +
> > + ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, buf);
> > + if (ret < 0) {
> > + dev_err(&client->dev, "Failed to read PMBUS_MFR_ID\n");
> > + return ret;
> > + }
> > + if (ret != 2 || strncmp(buf, "RI", strlen("RI"))) {
> > + dev_err(&client->dev, "MFR_ID unrecognised\n");
> > + return -ENODEV;
> > + }
> > +
> > + ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf);
> > + if (ret < 0) {
> > + dev_err(&client->dev, "Failed to read PMBUS_MFR_MODEL\n");
> > + return ret;
> > + }
> > + if (ret != 2 || !(buf[0] == 0x6c && buf[1] == 0x00)) {
> > + dev_err(&client->dev, "MFR_MODEL unrecognised\n");
> > + return -ENODEV;
> > + }
> > +
> > + info = devm_kzalloc(&client->dev, sizeof(struct pmbus_driver_info),
> > + GFP_KERNEL);
> > + if (!info)
> > + return -ENOMEM;
> > +
> > + info->write_word_data = ir35221_write_word_data;
> > + info->read_word_data = ir35221_read_word_data;
> > +
> > + info->pages = 2;
> > + info->format[PSC_VOLTAGE_IN] = linear;
> > + info->format[PSC_VOLTAGE_OUT] = linear;
> > + info->format[PSC_CURRENT_IN] = linear;
> > + info->format[PSC_CURRENT_OUT] = linear;
> > + info->format[PSC_POWER] = linear;
> > + info->format[PSC_TEMPERATURE] = linear;
> > +
> > + info->func[0] = PMBUS_HAVE_VIN
> > + | PMBUS_HAVE_VOUT | PMBUS_HAVE_IIN
> > + | PMBUS_HAVE_IOUT | PMBUS_HAVE_PIN
> > + | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
> > + | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
> > + | PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP;
> > + info->func[1] = info->func[0];
> > +
> > + return pmbus_do_probe(client, id, info);
> > +}
> > +
> > +static const struct i2c_device_id ir35221_id[] = {
> > + {"ir35221", 0},
> > + {}
> > +};
> > +
> > +MODULE_DEVICE_TABLE(i2c, ir35221_id);
> > +
> > +static struct i2c_driver ir35221_driver = {
> > + .driver = {
> > + .name = "ir35221",
> > + },
> > + .probe = ir35221_probe,
> > + .remove = pmbus_do_remove,
> > + .id_table = ir35221_id,
> > +};
> > +
> > +module_i2c_driver(ir35221_driver);
> > +
> > +MODULE_AUTHOR("Samuel Mendoza-Jonas <sam at mendozajonas.com");
> > +MODULE_DESCRIPTION("PMBus driver for IR35221");
> > +MODULE_LICENSE("GPL");
> >
>
>
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