* [PATCH linux hwmon-next v1 0/3] Add SB-TSI hwmon driver
@ 2020-03-19 22:48 Kun Yi
2020-03-19 22:48 ` [PATCH linux hwmon-next v1 1/3] hwmon: (sbtsi) Add basic support for SB-TSI sensors Kun Yi
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Kun Yi @ 2020-03-19 22:48 UTC (permalink / raw)
To: jdelvare, linux, robh+dt, mark.rutland
Cc: Kun Yi, openbmc, joel, linux-hwmon, devicetree, linux-kernel
*** BLURB HERE ***
This patchset adds hwmon support for AMD SoC SB-TSI emulated temperature
sensor and related documentation.
Kun Yi (3):
hwmon: (sbtsi) Add basic support for SB-TSI sensors
hwmon: (sbtsi) Add documentation
dt-bindings: (hwmon/sbtsi_tmep) Add SB-TSI hwmon driver bindings
.../devicetree/bindings/hwmon/sbtsi_temp.txt | 14 ++
Documentation/hwmon/sbtsi_temp.rst | 33 +++
drivers/hwmon/Kconfig | 10 +
drivers/hwmon/Makefile | 1 +
drivers/hwmon/sbtsi_temp.c | 218 ++++++++++++++++++
5 files changed, 276 insertions(+)
create mode 100644 Documentation/devicetree/bindings/hwmon/sbtsi_temp.txt
create mode 100644 Documentation/hwmon/sbtsi_temp.rst
create mode 100644 drivers/hwmon/sbtsi_temp.c
--
2.25.1.696.g5e7596f4ac-goog
^ permalink raw reply [flat|nested] 6+ messages in thread* [PATCH linux hwmon-next v1 1/3] hwmon: (sbtsi) Add basic support for SB-TSI sensors 2020-03-19 22:48 [PATCH linux hwmon-next v1 0/3] Add SB-TSI hwmon driver Kun Yi @ 2020-03-19 22:48 ` Kun Yi 2020-03-19 23:30 ` Guenter Roeck 2020-03-19 22:48 ` [PATCH linux hwmon-next v1 2/3] hwmon: (sbtsi) Add documentation Kun Yi 2020-03-19 22:48 ` [PATCH linux hwmon-next v1 3/3] dt-bindings: (hwmon/sbtsi_tmep) Add SB-TSI hwmon driver bindings Kun Yi 2 siblings, 1 reply; 6+ messages in thread From: Kun Yi @ 2020-03-19 22:48 UTC (permalink / raw) To: jdelvare, linux, robh+dt, mark.rutland Cc: Kun Yi, openbmc, joel, linux-hwmon, devicetree, linux-kernel SB Temperature Sensor Interface (SB-TSI) is an SMBus compatible interface that reports AMD SoC's Ttcl (normalized temperature), and resembles a typical 8-pin remote temperature sensor's I2C interface to BMC. This commit adds basic support using this interface to read CPU temperature, and read/write high/low CPU temp thresholds. Test status: tested reading temp1_input, and reading/writing temp1_max/min. Signed-off-by: Kun Yi <kunyi@google.com> --- drivers/hwmon/Kconfig | 10 ++ drivers/hwmon/Makefile | 1 + drivers/hwmon/sbtsi_temp.c | 218 +++++++++++++++++++++++++++++++++++++ 3 files changed, 229 insertions(+) create mode 100644 drivers/hwmon/sbtsi_temp.c diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 05a30832c6ba..9585dcd01d1b 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -1412,6 +1412,16 @@ config SENSORS_RASPBERRYPI_HWMON This driver can also be built as a module. If so, the module will be called raspberrypi-hwmon. +config SENSORS_SBTSI + tristate "Emulated SB-TSI temperature sensor" + depends on I2C + help + If you say yes here you get support for emulated temperature + sensors on AMD SoCs with SB-TSI interface connected to a BMC device. + + This driver can also be built as a module. If so, the module will + be called sbtsi_temp. + config SENSORS_SHT15 tristate "Sensiron humidity and temperature sensors. SHT15 and compat." depends on GPIOLIB || COMPILE_TEST diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index b0b9c8e57176..cd109f003ce4 100644 --- a/drivers/hwmon/Makefile +++ b/drivers/hwmon/Makefile @@ -152,6 +152,7 @@ obj-$(CONFIG_SENSORS_POWR1220) += powr1220.o obj-$(CONFIG_SENSORS_PWM_FAN) += pwm-fan.o obj-$(CONFIG_SENSORS_RASPBERRYPI_HWMON) += raspberrypi-hwmon.o obj-$(CONFIG_SENSORS_S3C) += s3c-hwmon.o +obj-$(CONFIG_SENSORS_SBTSI) += sbtsi_temp.o obj-$(CONFIG_SENSORS_SCH56XX_COMMON)+= sch56xx-common.o obj-$(CONFIG_SENSORS_SCH5627) += sch5627.o obj-$(CONFIG_SENSORS_SCH5636) += sch5636.o diff --git a/drivers/hwmon/sbtsi_temp.c b/drivers/hwmon/sbtsi_temp.c new file mode 100644 index 000000000000..f998d944a515 --- /dev/null +++ b/drivers/hwmon/sbtsi_temp.c @@ -0,0 +1,218 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * sbtsi_temp.c - hwmon driver for a SBI Temperature Sensor Interface (SB-TSI) + * compliant AMD SoC temperature device. + * + * Copyright (c) 2020, Google Inc. + * Copyright (c) 2020, Kun Yi <kunyi@google.com> + */ + +#include <linux/device.h> +#include <linux/init.h> +#include <linux/i2c.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/hwmon.h> +#include <linux/hwmon-sysfs.h> + +/* + * SB-TSI registers only support SMBus byte data access. "_INT" registers are + * the integer part of a temperature value or limit, and "_DEC" registers are + * corresponding decimal parts. + */ +#define SBTSI_REG_TEMP_INT 0x01 /* RO */ +#define SBTSI_REG_STATUS 0x02 /* RO */ +#define SBTSI_REG_CONFIG 0x03 /* RO */ +#define SBTSI_REG_TEMP_HIGH_INT 0x07 /* RW */ +#define SBTSI_REG_TEMP_LOW_INT 0x08 /* RW */ +#define SBTSI_REG_TEMP_DEC 0x10 /* RW */ +#define SBTSI_REG_TEMP_HIGH_DEC 0x13 /* RW */ +#define SBTSI_REG_TEMP_LOW_DEC 0x14 /* RW */ +#define SBTSI_REG_REV 0xFF /* RO */ + +#define SBTSI_CONFIG_READ_ORDER_SHIFT 5 + +#define SBTSI_TEMP_MIN (0) +#define SBTSI_TEMP_MAX (255875) +#define SBTSI_REV_MAX_VALID_ID (4) + +struct sbtsi_data { + struct device *dev; + struct i2c_client *client; + struct mutex lock; +}; + +/* + * From SB-TSI spec: CPU temperature readings and limit registers encode the + * temperature in increments of 0.125 from 0 to 255.875. The "high byte" + * register encodes the base-2 of the integer portion, and the upper 3 bits of + * the "low byte" encode in base-2 the decimal portion. + * + * e.g. INT=0x19, DEC=0x20 represents 25.125 degrees Celsius + * + * Therefore temperature in millidegree Celsius = + * (INT + DEC / 256) * 1000 = (INT * 8 + DEC / 32) * 125 + */ +static inline int SBTSI_REGS_TO_TEMP(s32 integer, s32 decimal) +{ + return (((u32)integer << 3) + ((u32)decimal >> 5)) * 125; +} + +/* + * Inversely, given temperature in millidegree Celsius + * INT = (TEMP / 125) / 8 + * DEC = ((TEMP / 125) % 8) * 32 + * Caller have to make sure temp doesn't exceed 255875, the max valid value. + */ +static inline void SBTSI_TEMP_TO_REGS(u32 temp, u8 *integer, u8 *decimal) +{ + temp /= 125; + *integer = temp >> 3; + *decimal = (temp & 0x7) << 5; +} + +static ssize_t sbtsi_show_temp(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct sbtsi_data *data = dev_get_drvdata(dev); + struct i2c_client *client = data->client; + s32 err, temp_int, temp_dec; + u8 read_order; + + /* + * ReadOrder bit specifies the reading order of integer and decimal + * part of CPU temp for atomic reads. If bit == 0, reading integer part + * triggers latching of the decimal part, so integer part should be read + * first. If bit == 1, read order should be reversed. + */ + err = i2c_smbus_read_byte_data(client, SBTSI_REG_CONFIG); + if (err < 0) + return err; + + read_order = (u8)err & BIT(SBTSI_CONFIG_READ_ORDER_SHIFT); + + if (read_order == 0) { + temp_int = i2c_smbus_read_byte_data(client, SBTSI_REG_TEMP_INT); + temp_dec = i2c_smbus_read_byte_data(client, SBTSI_REG_TEMP_DEC); + } else { + temp_dec = i2c_smbus_read_byte_data(client, SBTSI_REG_TEMP_DEC); + temp_int = i2c_smbus_read_byte_data(client, SBTSI_REG_TEMP_INT); + } + + if (temp_int < 0) + return temp_int; + if (temp_dec < 0) + return temp_dec; + + return scnprintf(buf, PAGE_SIZE, "%d\n", + SBTSI_REGS_TO_TEMP(temp_int, temp_dec)); +} + +#define sbtsi_show_temp_limit(name, REG) \ +static ssize_t sbtsi_show_##name(struct device *dev, \ + struct device_attribute *attr, char *buf) \ +{ \ + struct sbtsi_data *data = dev_get_drvdata(dev); \ + struct i2c_client *client = data->client; \ + s32 temp_int, temp_dec; \ +\ + temp_int = i2c_smbus_read_byte_data(client, REG##_INT); \ + temp_dec = i2c_smbus_read_byte_data(client, REG##_DEC); \ +\ + if (temp_int < 0) \ + return temp_int; \ + if (temp_dec < 0) \ + return temp_dec; \ +\ + return scnprintf(buf, PAGE_SIZE, "%d\n", \ + SBTSI_REGS_TO_TEMP(temp_int, temp_dec)); \ +} + +sbtsi_show_temp_limit(temp1_min, SBTSI_REG_TEMP_LOW); +sbtsi_show_temp_limit(temp1_max, SBTSI_REG_TEMP_HIGH); + +#define sbtsi_set_temp_limit(name, REG) \ +static ssize_t sbtsi_set_##name(struct device *dev, \ + struct device_attribute *attr, \ + const char *buf, size_t count) \ +{ \ + struct sbtsi_data *data = dev_get_drvdata(dev); \ + struct i2c_client *client = data->client; \ + long val; \ + u8 temp_int, temp_dec; \ + int err = kstrtol(buf, 10, &val); \ + if (err) \ + return err; \ +\ + val = clamp_val(val, SBTSI_TEMP_MIN, SBTSI_TEMP_MAX); \ + mutex_lock(&data->lock); \ + SBTSI_TEMP_TO_REGS(val, &temp_int, &temp_dec); \ + i2c_smbus_write_byte_data(client, REG##_INT, temp_int); \ + i2c_smbus_write_byte_data(client, REG##_DEC, temp_dec); \ + mutex_unlock(&data->lock); \ +\ + return count; \ +} + +sbtsi_set_temp_limit(temp1_min, SBTSI_REG_TEMP_LOW); +sbtsi_set_temp_limit(temp1_max, SBTSI_REG_TEMP_HIGH); + +static SENSOR_DEVICE_ATTR(temp1_input, 0444, sbtsi_show_temp, NULL, 0); +static SENSOR_DEVICE_ATTR(temp1_min, 0644, sbtsi_show_temp1_min, + sbtsi_set_temp1_min, 1); +static SENSOR_DEVICE_ATTR(temp1_max, 0644, sbtsi_show_temp1_max, + sbtsi_set_temp1_max, 2); + +static struct attribute *sbtsi_attrs[] = { + &sensor_dev_attr_temp1_input.dev_attr.attr, + &sensor_dev_attr_temp1_min.dev_attr.attr, + &sensor_dev_attr_temp1_max.dev_attr.attr, + NULL, +}; +ATTRIBUTE_GROUPS(sbtsi); + +static int sbtsi_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct device *dev = &client->dev; + struct device *hwmon_dev; + struct sbtsi_data *data; + + data = devm_kzalloc(dev, sizeof(struct sbtsi_data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->client = client; + mutex_init(&data->lock); + + hwmon_dev = + devm_hwmon_device_register_with_groups(dev, client->name, data, + sbtsi_groups); + if (IS_ERR(hwmon_dev)) + return PTR_ERR(hwmon_dev); + + dev_info(dev, "sensor '%s'\n", client->name); + + return 0; +} + +static const struct i2c_device_id sbtsi_id[] = { + {"sbtsi", 0}, + {} +}; +MODULE_DEVICE_TABLE(i2c, sbtsi_id); + +static struct i2c_driver sbtsi_driver = { + .class = I2C_CLASS_HWMON, + .driver = { + .name = "sbtsi", + }, + .probe = sbtsi_probe, + .id_table = sbtsi_id, +}; + +module_i2c_driver(sbtsi_driver); + +MODULE_AUTHOR("Kun Yi <kunyi@google.com>"); +MODULE_DESCRIPTION("Hwmon driver for AMD SB-TSI emulated sensor"); +MODULE_LICENSE("GPL"); -- 2.25.1.696.g5e7596f4ac-goog ^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH linux hwmon-next v1 1/3] hwmon: (sbtsi) Add basic support for SB-TSI sensors 2020-03-19 22:48 ` [PATCH linux hwmon-next v1 1/3] hwmon: (sbtsi) Add basic support for SB-TSI sensors Kun Yi @ 2020-03-19 23:30 ` Guenter Roeck 2020-03-23 23:25 ` Kun Yi 0 siblings, 1 reply; 6+ messages in thread From: Guenter Roeck @ 2020-03-19 23:30 UTC (permalink / raw) To: Kun Yi, jdelvare, robh+dt, mark.rutland Cc: openbmc, joel, linux-hwmon, devicetree, linux-kernel On 3/19/20 3:48 PM, Kun Yi wrote: > SB Temperature Sensor Interface (SB-TSI) is an SMBus compatible > interface that reports AMD SoC's Ttcl (normalized temperature), > and resembles a typical 8-pin remote temperature sensor's I2C interface > to BMC. > > This commit adds basic support using this interface to read CPU > temperature, and read/write high/low CPU temp thresholds. > > Test status: tested reading temp1_input, and reading/writing > temp1_max/min. > How do I instantiate this driver on a system with an AMD CPU (in other words, what is the i2c bus and the i2c address) ? > Signed-off-by: Kun Yi <kunyi@google.com> > --- > drivers/hwmon/Kconfig | 10 ++ > drivers/hwmon/Makefile | 1 + > drivers/hwmon/sbtsi_temp.c | 218 +++++++++++++++++++++++++++++++++++++ > 3 files changed, 229 insertions(+) > create mode 100644 drivers/hwmon/sbtsi_temp.c > > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > index 05a30832c6ba..9585dcd01d1b 100644 > --- a/drivers/hwmon/Kconfig > +++ b/drivers/hwmon/Kconfig > @@ -1412,6 +1412,16 @@ config SENSORS_RASPBERRYPI_HWMON > This driver can also be built as a module. If so, the module > will be called raspberrypi-hwmon. > > +config SENSORS_SBTSI > + tristate "Emulated SB-TSI temperature sensor" > + depends on I2C > + help > + If you say yes here you get support for emulated temperature > + sensors on AMD SoCs with SB-TSI interface connected to a BMC device. > + > + This driver can also be built as a module. If so, the module will > + be called sbtsi_temp. > + > config SENSORS_SHT15 > tristate "Sensiron humidity and temperature sensors. SHT15 and compat." > depends on GPIOLIB || COMPILE_TEST > diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile > index b0b9c8e57176..cd109f003ce4 100644 > --- a/drivers/hwmon/Makefile > +++ b/drivers/hwmon/Makefile > @@ -152,6 +152,7 @@ obj-$(CONFIG_SENSORS_POWR1220) += powr1220.o > obj-$(CONFIG_SENSORS_PWM_FAN) += pwm-fan.o > obj-$(CONFIG_SENSORS_RASPBERRYPI_HWMON) += raspberrypi-hwmon.o > obj-$(CONFIG_SENSORS_S3C) += s3c-hwmon.o > +obj-$(CONFIG_SENSORS_SBTSI) += sbtsi_temp.o > obj-$(CONFIG_SENSORS_SCH56XX_COMMON)+= sch56xx-common.o > obj-$(CONFIG_SENSORS_SCH5627) += sch5627.o > obj-$(CONFIG_SENSORS_SCH5636) += sch5636.o > diff --git a/drivers/hwmon/sbtsi_temp.c b/drivers/hwmon/sbtsi_temp.c > new file mode 100644 > index 000000000000..f998d944a515 > --- /dev/null > +++ b/drivers/hwmon/sbtsi_temp.c > @@ -0,0 +1,218 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * sbtsi_temp.c - hwmon driver for a SBI Temperature Sensor Interface (SB-TSI) > + * compliant AMD SoC temperature device. > + * > + * Copyright (c) 2020, Google Inc. > + * Copyright (c) 2020, Kun Yi <kunyi@google.com> > + */ > + > +#include <linux/device.h> > +#include <linux/init.h> > +#include <linux/i2c.h> > +#include <linux/module.h> > +#include <linux/mutex.h> > +#include <linux/hwmon.h> > +#include <linux/hwmon-sysfs.h> > + > +/* > + * SB-TSI registers only support SMBus byte data access. "_INT" registers are > + * the integer part of a temperature value or limit, and "_DEC" registers are > + * corresponding decimal parts. > + */ > +#define SBTSI_REG_TEMP_INT 0x01 /* RO */ > +#define SBTSI_REG_STATUS 0x02 /* RO */ > +#define SBTSI_REG_CONFIG 0x03 /* RO */ > +#define SBTSI_REG_TEMP_HIGH_INT 0x07 /* RW */ > +#define SBTSI_REG_TEMP_LOW_INT 0x08 /* RW */ > +#define SBTSI_REG_TEMP_DEC 0x10 /* RW */ > +#define SBTSI_REG_TEMP_HIGH_DEC 0x13 /* RW */ > +#define SBTSI_REG_TEMP_LOW_DEC 0x14 /* RW */ > +#define SBTSI_REG_REV 0xFF /* RO */ > + > +#define SBTSI_CONFIG_READ_ORDER_SHIFT 5 > + > +#define SBTSI_TEMP_MIN (0) > +#define SBTSI_TEMP_MAX (255875) > +#define SBTSI_REV_MAX_VALID_ID (4) Unnecessary ( ) around literals. > + > +struct sbtsi_data { > + struct device *dev; > + struct i2c_client *client; > + struct mutex lock; > +}; > + > +/* > + * From SB-TSI spec: CPU temperature readings and limit registers encode the > + * temperature in increments of 0.125 from 0 to 255.875. The "high byte" > + * register encodes the base-2 of the integer portion, and the upper 3 bits of > + * the "low byte" encode in base-2 the decimal portion. > + * > + * e.g. INT=0x19, DEC=0x20 represents 25.125 degrees Celsius > + * > + * Therefore temperature in millidegree Celsius = > + * (INT + DEC / 256) * 1000 = (INT * 8 + DEC / 32) * 125 > + */ > +static inline int SBTSI_REGS_TO_TEMP(s32 integer, s32 decimal) > +{ > + return (((u32)integer << 3) + ((u32)decimal >> 5)) * 125; Why pass s32 as parameter just to typecast to u32 ? The values are known to be between 0 and 255, and thus will never be negative, even with s32, so this is really unnecessary. > +} > + > +/* > + * Inversely, given temperature in millidegree Celsius > + * INT = (TEMP / 125) / 8 > + * DEC = ((TEMP / 125) % 8) * 32 > + * Caller have to make sure temp doesn't exceed 255875, the max valid value. > + */ > +static inline void SBTSI_TEMP_TO_REGS(u32 temp, u8 *integer, u8 *decimal) > +{ > + temp /= 125; > + *integer = temp >> 3; > + *decimal = (temp & 0x7) << 5; > +} > + > +static ssize_t sbtsi_show_temp(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + struct sbtsi_data *data = dev_get_drvdata(dev); > + struct i2c_client *client = data->client; > + s32 err, temp_int, temp_dec; > + u8 read_order; > + > + /* > + * ReadOrder bit specifies the reading order of integer and decimal > + * part of CPU temp for atomic reads. If bit == 0, reading integer part > + * triggers latching of the decimal part, so integer part should be read > + * first. If bit == 1, read order should be reversed. > + */ > + err = i2c_smbus_read_byte_data(client, SBTSI_REG_CONFIG); > + if (err < 0) > + return err; > + > + read_order = (u8)err & BIT(SBTSI_CONFIG_READ_ORDER_SHIFT); > + > + if (read_order == 0) { > + temp_int = i2c_smbus_read_byte_data(client, SBTSI_REG_TEMP_INT); > + temp_dec = i2c_smbus_read_byte_data(client, SBTSI_REG_TEMP_DEC); > + } else { > + temp_dec = i2c_smbus_read_byte_data(client, SBTSI_REG_TEMP_DEC); > + temp_int = i2c_smbus_read_byte_data(client, SBTSI_REG_TEMP_INT); > + } > + > + if (temp_int < 0) > + return temp_int; > + if (temp_dec < 0) > + return temp_dec; > + > + return scnprintf(buf, PAGE_SIZE, "%d\n", > + SBTSI_REGS_TO_TEMP(temp_int, temp_dec)); > +} > + > +#define sbtsi_show_temp_limit(name, REG) \ > +static ssize_t sbtsi_show_##name(struct device *dev, \ > + struct device_attribute *attr, char *buf) \ > +{ \ > + struct sbtsi_data *data = dev_get_drvdata(dev); \ > + struct i2c_client *client = data->client; \ > + s32 temp_int, temp_dec; \ > +\ > + temp_int = i2c_smbus_read_byte_data(client, REG##_INT); \ > + temp_dec = i2c_smbus_read_byte_data(client, REG##_DEC); \ > +\ > + if (temp_int < 0) \ > + return temp_int; \ > + if (temp_dec < 0) \ > + return temp_dec; \ > +\ > + return scnprintf(buf, PAGE_SIZE, "%d\n", \ > + SBTSI_REGS_TO_TEMP(temp_int, temp_dec)); \ > +} > + > +sbtsi_show_temp_limit(temp1_min, SBTSI_REG_TEMP_LOW); > +sbtsi_show_temp_limit(temp1_max, SBTSI_REG_TEMP_HIGH); > + > +#define sbtsi_set_temp_limit(name, REG) \ > +static ssize_t sbtsi_set_##name(struct device *dev, \ > + struct device_attribute *attr, \ > + const char *buf, size_t count) \ > +{ \ > + struct sbtsi_data *data = dev_get_drvdata(dev); \ > + struct i2c_client *client = data->client; \ > + long val; \ > + u8 temp_int, temp_dec; \ > + int err = kstrtol(buf, 10, &val); \ > + if (err) \ > + return err; \ > +\ > + val = clamp_val(val, SBTSI_TEMP_MIN, SBTSI_TEMP_MAX); \ > + mutex_lock(&data->lock); \ > + SBTSI_TEMP_TO_REGS(val, &temp_int, &temp_dec); \ > + i2c_smbus_write_byte_data(client, REG##_INT, temp_int); \ > + i2c_smbus_write_byte_data(client, REG##_DEC, temp_dec); \ > + mutex_unlock(&data->lock); \ > +\ > + return count; \ > +} > + > +sbtsi_set_temp_limit(temp1_min, SBTSI_REG_TEMP_LOW); > +sbtsi_set_temp_limit(temp1_max, SBTSI_REG_TEMP_HIGH); > + > +static SENSOR_DEVICE_ATTR(temp1_input, 0444, sbtsi_show_temp, NULL, 0); > +static SENSOR_DEVICE_ATTR(temp1_min, 0644, sbtsi_show_temp1_min, > + sbtsi_set_temp1_min, 1); > +static SENSOR_DEVICE_ATTR(temp1_max, 0644, sbtsi_show_temp1_max, > + sbtsi_set_temp1_max, 2); > + > +static struct attribute *sbtsi_attrs[] = { > + &sensor_dev_attr_temp1_input.dev_attr.attr, > + &sensor_dev_attr_temp1_min.dev_attr.attr, > + &sensor_dev_attr_temp1_max.dev_attr.attr, > + NULL, > +}; > +ATTRIBUTE_GROUPS(sbtsi); > + > +static int sbtsi_probe(struct i2c_client *client, > + const struct i2c_device_id *id) > +{ > + struct device *dev = &client->dev; > + struct device *hwmon_dev; > + struct sbtsi_data *data; > + > + data = devm_kzalloc(dev, sizeof(struct sbtsi_data), GFP_KERNEL); > + if (!data) > + return -ENOMEM; > + > + data->client = client; > + mutex_init(&data->lock); > + > + hwmon_dev = > + devm_hwmon_device_register_with_groups(dev, client->name, data, > + sbtsi_groups); Please rewrite to use the devm_hwmon_device_register_with_info() API. > + if (IS_ERR(hwmon_dev)) > + return PTR_ERR(hwmon_dev); > + > + dev_info(dev, "sensor '%s'\n", client->name); Is that really valuable / necessary ? > + > + return 0; > +} > + > +static const struct i2c_device_id sbtsi_id[] = { > + {"sbtsi", 0}, > + {} > +}; > +MODULE_DEVICE_TABLE(i2c, sbtsi_id); > + > +static struct i2c_driver sbtsi_driver = { > + .class = I2C_CLASS_HWMON, > + .driver = { > + .name = "sbtsi", > + }, > + .probe = sbtsi_probe, > + .id_table = sbtsi_id, > +}; > + > +module_i2c_driver(sbtsi_driver); > + > +MODULE_AUTHOR("Kun Yi <kunyi@google.com>"); > +MODULE_DESCRIPTION("Hwmon driver for AMD SB-TSI emulated sensor"); > +MODULE_LICENSE("GPL"); > ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH linux hwmon-next v1 1/3] hwmon: (sbtsi) Add basic support for SB-TSI sensors 2020-03-19 23:30 ` Guenter Roeck @ 2020-03-23 23:25 ` Kun Yi 0 siblings, 0 replies; 6+ messages in thread From: Kun Yi @ 2020-03-23 23:25 UTC (permalink / raw) To: Guenter Roeck Cc: jdelvare, robh+dt, mark.rutland, OpenBMC Maillist, Joel Stanley, linux-hwmon, devicetree, linux-kernel Thanks for the review comments! On Thu, Mar 19, 2020 at 4:31 PM Guenter Roeck <linux@roeck-us.net> wrote: > > On 3/19/20 3:48 PM, Kun Yi wrote: > > SB Temperature Sensor Interface (SB-TSI) is an SMBus compatible > > interface that reports AMD SoC's Ttcl (normalized temperature), > > and resembles a typical 8-pin remote temperature sensor's I2C interface > > to BMC. > > > > This commit adds basic support using this interface to read CPU > > temperature, and read/write high/low CPU temp thresholds. > > > > Test status: tested reading temp1_input, and reading/writing > > temp1_max/min. > > > > How do I instantiate this driver on a system with an AMD CPU > (in other words, what is the i2c bus and the i2c address) ? The i2c bus number would be the bus connected from BMC to the AMD CPU. The i2c address is specified in the spec: Section 6.3.1: The SB-TSI address is normally 98h for socket 0 and 90h for socket 1, but it could vary based on hardware address select pins. I will add this information to v2 commit message and the Documentation. > > > Signed-off-by: Kun Yi <kunyi@google.com> > > --- > > drivers/hwmon/Kconfig | 10 ++ > > drivers/hwmon/Makefile | 1 + > > drivers/hwmon/sbtsi_temp.c | 218 +++++++++++++++++++++++++++++++++++++ > > 3 files changed, 229 insertions(+) > > create mode 100644 drivers/hwmon/sbtsi_temp.c > > > > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > > index 05a30832c6ba..9585dcd01d1b 100644 > > --- a/drivers/hwmon/Kconfig > > +++ b/drivers/hwmon/Kconfig > > @@ -1412,6 +1412,16 @@ config SENSORS_RASPBERRYPI_HWMON > > This driver can also be built as a module. If so, the module > > will be called raspberrypi-hwmon. > > > > +config SENSORS_SBTSI > > + tristate "Emulated SB-TSI temperature sensor" > > + depends on I2C > > + help > > + If you say yes here you get support for emulated temperature > > + sensors on AMD SoCs with SB-TSI interface connected to a BMC device. > > + > > + This driver can also be built as a module. If so, the module will > > + be called sbtsi_temp. > > + > > config SENSORS_SHT15 > > tristate "Sensiron humidity and temperature sensors. SHT15 and compat." > > depends on GPIOLIB || COMPILE_TEST > > diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile > > index b0b9c8e57176..cd109f003ce4 100644 > > --- a/drivers/hwmon/Makefile > > +++ b/drivers/hwmon/Makefile > > @@ -152,6 +152,7 @@ obj-$(CONFIG_SENSORS_POWR1220) += powr1220.o > > obj-$(CONFIG_SENSORS_PWM_FAN) += pwm-fan.o > > obj-$(CONFIG_SENSORS_RASPBERRYPI_HWMON) += raspberrypi-hwmon.o > > obj-$(CONFIG_SENSORS_S3C) += s3c-hwmon.o > > +obj-$(CONFIG_SENSORS_SBTSI) += sbtsi_temp.o > > obj-$(CONFIG_SENSORS_SCH56XX_COMMON)+= sch56xx-common.o > > obj-$(CONFIG_SENSORS_SCH5627) += sch5627.o > > obj-$(CONFIG_SENSORS_SCH5636) += sch5636.o > > diff --git a/drivers/hwmon/sbtsi_temp.c b/drivers/hwmon/sbtsi_temp.c > > new file mode 100644 > > index 000000000000..f998d944a515 > > --- /dev/null > > +++ b/drivers/hwmon/sbtsi_temp.c > > @@ -0,0 +1,218 @@ > > +// SPDX-License-Identifier: GPL-2.0-or-later > > +/* > > + * sbtsi_temp.c - hwmon driver for a SBI Temperature Sensor Interface (SB-TSI) > > + * compliant AMD SoC temperature device. > > + * > > + * Copyright (c) 2020, Google Inc. > > + * Copyright (c) 2020, Kun Yi <kunyi@google.com> > > + */ > > + > > +#include <linux/device.h> > > +#include <linux/init.h> > > +#include <linux/i2c.h> > > +#include <linux/module.h> > > +#include <linux/mutex.h> > > +#include <linux/hwmon.h> > > +#include <linux/hwmon-sysfs.h> > > + > > +/* > > + * SB-TSI registers only support SMBus byte data access. "_INT" registers are > > + * the integer part of a temperature value or limit, and "_DEC" registers are > > + * corresponding decimal parts. > > + */ > > +#define SBTSI_REG_TEMP_INT 0x01 /* RO */ > > +#define SBTSI_REG_STATUS 0x02 /* RO */ > > +#define SBTSI_REG_CONFIG 0x03 /* RO */ > > +#define SBTSI_REG_TEMP_HIGH_INT 0x07 /* RW */ > > +#define SBTSI_REG_TEMP_LOW_INT 0x08 /* RW */ > > +#define SBTSI_REG_TEMP_DEC 0x10 /* RW */ > > +#define SBTSI_REG_TEMP_HIGH_DEC 0x13 /* RW */ > > +#define SBTSI_REG_TEMP_LOW_DEC 0x14 /* RW */ > > +#define SBTSI_REG_REV 0xFF /* RO */ > > + > > +#define SBTSI_CONFIG_READ_ORDER_SHIFT 5 > > + > > +#define SBTSI_TEMP_MIN (0) > > +#define SBTSI_TEMP_MAX (255875) > > +#define SBTSI_REV_MAX_VALID_ID (4) > > Unnecessary ( ) around literals. Will fix in v2. > > > + > > +struct sbtsi_data { > > + struct device *dev; > > + struct i2c_client *client; > > + struct mutex lock; > > +}; > > + > > +/* > > + * From SB-TSI spec: CPU temperature readings and limit registers encode the > > + * temperature in increments of 0.125 from 0 to 255.875. The "high byte" > > + * register encodes the base-2 of the integer portion, and the upper 3 bits of > > + * the "low byte" encode in base-2 the decimal portion. > > + * > > + * e.g. INT=0x19, DEC=0x20 represents 25.125 degrees Celsius > > + * > > + * Therefore temperature in millidegree Celsius = > > + * (INT + DEC / 256) * 1000 = (INT * 8 + DEC / 32) * 125 > > + */ > > +static inline int SBTSI_REGS_TO_TEMP(s32 integer, s32 decimal) > > +{ > > + return (((u32)integer << 3) + ((u32)decimal >> 5)) * 125; > > Why pass s32 as parameter just to typecast to u32 ? The values > are known to be between 0 and 255, and thus will never be negative, > even with s32, so this is really unnecessary. That's a good point, will fix in v2. > > +} > > + > > +/* > > + * Inversely, given temperature in millidegree Celsius > > + * INT = (TEMP / 125) / 8 > > + * DEC = ((TEMP / 125) % 8) * 32 > > + * Caller have to make sure temp doesn't exceed 255875, the max valid value. > > + */ > > +static inline void SBTSI_TEMP_TO_REGS(u32 temp, u8 *integer, u8 *decimal) > > +{ > > + temp /= 125; > > + *integer = temp >> 3; > > + *decimal = (temp & 0x7) << 5; > > +} > > + > > +static ssize_t sbtsi_show_temp(struct device *dev, > > + struct device_attribute *attr, char *buf) > > +{ > > + struct sbtsi_data *data = dev_get_drvdata(dev); > > + struct i2c_client *client = data->client; > > + s32 err, temp_int, temp_dec; > > + u8 read_order; > > + > > + /* > > + * ReadOrder bit specifies the reading order of integer and decimal > > + * part of CPU temp for atomic reads. If bit == 0, reading integer part > > + * triggers latching of the decimal part, so integer part should be read > > + * first. If bit == 1, read order should be reversed. > > + */ > > + err = i2c_smbus_read_byte_data(client, SBTSI_REG_CONFIG); > > + if (err < 0) > > + return err; > > + > > + read_order = (u8)err & BIT(SBTSI_CONFIG_READ_ORDER_SHIFT); > > + > > + if (read_order == 0) { > > + temp_int = i2c_smbus_read_byte_data(client, SBTSI_REG_TEMP_INT); > > + temp_dec = i2c_smbus_read_byte_data(client, SBTSI_REG_TEMP_DEC); > > + } else { > > + temp_dec = i2c_smbus_read_byte_data(client, SBTSI_REG_TEMP_DEC); > > + temp_int = i2c_smbus_read_byte_data(client, SBTSI_REG_TEMP_INT); > > + } > > + > > + if (temp_int < 0) > > + return temp_int; > > + if (temp_dec < 0) > > + return temp_dec; > > + > > + return scnprintf(buf, PAGE_SIZE, "%d\n", > > + SBTSI_REGS_TO_TEMP(temp_int, temp_dec)); > > +} > > + > > +#define sbtsi_show_temp_limit(name, REG) \ > > +static ssize_t sbtsi_show_##name(struct device *dev, \ > > + struct device_attribute *attr, char *buf) \ > > +{ \ > > + struct sbtsi_data *data = dev_get_drvdata(dev); \ > > + struct i2c_client *client = data->client; \ > > + s32 temp_int, temp_dec; \ > > +\ > > + temp_int = i2c_smbus_read_byte_data(client, REG##_INT); \ > > + temp_dec = i2c_smbus_read_byte_data(client, REG##_DEC); \ > > +\ > > + if (temp_int < 0) \ > > + return temp_int; \ > > + if (temp_dec < 0) \ > > + return temp_dec; \ > > +\ > > + return scnprintf(buf, PAGE_SIZE, "%d\n", \ > > + SBTSI_REGS_TO_TEMP(temp_int, temp_dec)); \ > > +} > > + > > +sbtsi_show_temp_limit(temp1_min, SBTSI_REG_TEMP_LOW); > > +sbtsi_show_temp_limit(temp1_max, SBTSI_REG_TEMP_HIGH); > > + > > +#define sbtsi_set_temp_limit(name, REG) \ > > +static ssize_t sbtsi_set_##name(struct device *dev, \ > > + struct device_attribute *attr, \ > > + const char *buf, size_t count) \ > > +{ \ > > + struct sbtsi_data *data = dev_get_drvdata(dev); \ > > + struct i2c_client *client = data->client; \ > > + long val; \ > > + u8 temp_int, temp_dec; \ > > + int err = kstrtol(buf, 10, &val); \ > > + if (err) \ > > + return err; \ > > +\ > > + val = clamp_val(val, SBTSI_TEMP_MIN, SBTSI_TEMP_MAX); \ > > + mutex_lock(&data->lock); \ > > + SBTSI_TEMP_TO_REGS(val, &temp_int, &temp_dec); \ > > + i2c_smbus_write_byte_data(client, REG##_INT, temp_int); \ > > + i2c_smbus_write_byte_data(client, REG##_DEC, temp_dec); \ > > + mutex_unlock(&data->lock); \ > > +\ > > + return count; \ > > +} > > + > > +sbtsi_set_temp_limit(temp1_min, SBTSI_REG_TEMP_LOW); > > +sbtsi_set_temp_limit(temp1_max, SBTSI_REG_TEMP_HIGH); > > + > > +static SENSOR_DEVICE_ATTR(temp1_input, 0444, sbtsi_show_temp, NULL, 0); > > +static SENSOR_DEVICE_ATTR(temp1_min, 0644, sbtsi_show_temp1_min, > > + sbtsi_set_temp1_min, 1); > > +static SENSOR_DEVICE_ATTR(temp1_max, 0644, sbtsi_show_temp1_max, > > + sbtsi_set_temp1_max, 2); > > + > > +static struct attribute *sbtsi_attrs[] = { > > + &sensor_dev_attr_temp1_input.dev_attr.attr, > > + &sensor_dev_attr_temp1_min.dev_attr.attr, > > + &sensor_dev_attr_temp1_max.dev_attr.attr, > > + NULL, > > +}; > > +ATTRIBUTE_GROUPS(sbtsi); > > + > > +static int sbtsi_probe(struct i2c_client *client, > > + const struct i2c_device_id *id) > > +{ > > + struct device *dev = &client->dev; > > + struct device *hwmon_dev; > > + struct sbtsi_data *data; > > + > > + data = devm_kzalloc(dev, sizeof(struct sbtsi_data), GFP_KERNEL); > > + if (!data) > > + return -ENOMEM; > > + > > + data->client = client; > > + mutex_init(&data->lock); > > + > > + hwmon_dev = > > + devm_hwmon_device_register_with_groups(dev, client->name, data, > > + sbtsi_groups); > > Please rewrite to use the devm_hwmon_device_register_with_info() API. Done in v2. > > > + if (IS_ERR(hwmon_dev)) > > + return PTR_ERR(hwmon_dev); > > + > > + dev_info(dev, "sensor '%s'\n", client->name); > > Is that really valuable / necessary ? Removed in v2. > > > + > > + return 0; > > +} > > + > > +static const struct i2c_device_id sbtsi_id[] = { > > + {"sbtsi", 0}, > > + {} > > +}; > > +MODULE_DEVICE_TABLE(i2c, sbtsi_id); > > + > > +static struct i2c_driver sbtsi_driver = { > > + .class = I2C_CLASS_HWMON, > > + .driver = { > > + .name = "sbtsi", > > + }, > > + .probe = sbtsi_probe, > > + .id_table = sbtsi_id, > > +}; > > + > > +module_i2c_driver(sbtsi_driver); > > + > > +MODULE_AUTHOR("Kun Yi <kunyi@google.com>"); > > +MODULE_DESCRIPTION("Hwmon driver for AMD SB-TSI emulated sensor"); > > +MODULE_LICENSE("GPL"); > > > -- Regards, Kun ^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH linux hwmon-next v1 2/3] hwmon: (sbtsi) Add documentation 2020-03-19 22:48 [PATCH linux hwmon-next v1 0/3] Add SB-TSI hwmon driver Kun Yi 2020-03-19 22:48 ` [PATCH linux hwmon-next v1 1/3] hwmon: (sbtsi) Add basic support for SB-TSI sensors Kun Yi @ 2020-03-19 22:48 ` Kun Yi 2020-03-19 22:48 ` [PATCH linux hwmon-next v1 3/3] dt-bindings: (hwmon/sbtsi_tmep) Add SB-TSI hwmon driver bindings Kun Yi 2 siblings, 0 replies; 6+ messages in thread From: Kun Yi @ 2020-03-19 22:48 UTC (permalink / raw) To: jdelvare, linux, robh+dt, mark.rutland Cc: Kun Yi, openbmc, joel, linux-hwmon, devicetree, linux-kernel Document the SB-TSI sensor interface driver. Signed-off-by: Kun Yi <kunyi@google.com> --- Documentation/hwmon/sbtsi_temp.rst | 33 ++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100644 Documentation/hwmon/sbtsi_temp.rst diff --git a/Documentation/hwmon/sbtsi_temp.rst b/Documentation/hwmon/sbtsi_temp.rst new file mode 100644 index 000000000000..f5addb72d13f --- /dev/null +++ b/Documentation/hwmon/sbtsi_temp.rst @@ -0,0 +1,33 @@ +Kernel driver sbtsi_temp +================== + +Supported hardware: + + * Sideband interface (SBI) Temperature Sensor Interface (SB-TSI) + compliant AMD SoC temperature device. + + Prefix: 'sbtsi_temp' + + Addresses scanned: This driver doesn't support address scanning. + + Datasheet: The SB-TSI interface and protocol is available as part of + the open source SoC register reference at: + + https://www.amd.com/system/files/TechDocs/56255_OSRR.pdf + + The Advanced Platform Management Link (APML) Specification is + available at: + + http://developer.amd.com/wordpress/media/2012/10/41918.pdf + +Author: Kun Yi <kunyi@google.com> + +Description +----------- + +The SBI temperature sensor interface (SB-TSI) is an emulation of the software +and physical interface of a typical 8-pin remote temperature sensor (RTS) on +AMD SoCs. It implements one temperature sensor with readings and limit +registers encode the temperature in increments of 0.125 from 0 to 255.875. +Limits can be set through the writable thresholds, and if reached will trigger +corresponding alert signals. -- 2.25.1.696.g5e7596f4ac-goog ^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH linux hwmon-next v1 3/3] dt-bindings: (hwmon/sbtsi_tmep) Add SB-TSI hwmon driver bindings 2020-03-19 22:48 [PATCH linux hwmon-next v1 0/3] Add SB-TSI hwmon driver Kun Yi 2020-03-19 22:48 ` [PATCH linux hwmon-next v1 1/3] hwmon: (sbtsi) Add basic support for SB-TSI sensors Kun Yi 2020-03-19 22:48 ` [PATCH linux hwmon-next v1 2/3] hwmon: (sbtsi) Add documentation Kun Yi @ 2020-03-19 22:48 ` Kun Yi 2 siblings, 0 replies; 6+ messages in thread From: Kun Yi @ 2020-03-19 22:48 UTC (permalink / raw) To: jdelvare, linux, robh+dt, mark.rutland Cc: Kun Yi, openbmc, joel, linux-hwmon, devicetree, linux-kernel Document device tree bindings for AMD SB-TSI emulated temperature sensor. Signed-off-by: Kun Yi <kunyi@google.com> --- .../devicetree/bindings/hwmon/sbtsi_temp.txt | 14 ++++++++++++++ 1 file changed, 14 insertions(+) create mode 100644 Documentation/devicetree/bindings/hwmon/sbtsi_temp.txt diff --git a/Documentation/devicetree/bindings/hwmon/sbtsi_temp.txt b/Documentation/devicetree/bindings/hwmon/sbtsi_temp.txt new file mode 100644 index 000000000000..4020f075699e --- /dev/null +++ b/Documentation/devicetree/bindings/hwmon/sbtsi_temp.txt @@ -0,0 +1,14 @@ +*AMD SoC SB-TSI hwmon driver. + +Required properties: +- compatible: manufacturer and chip name, should be + "amd,sbtsi", + +- reg: I2C bus address of the device + +Example: + +sbtsi@4c { + compatible = "amd,sbtsi"; + reg = <0x4c>; +}; -- 2.25.1.696.g5e7596f4ac-goog ^ permalink raw reply related [flat|nested] 6+ messages in thread
end of thread, other threads:[~2020-03-23 23:25 UTC | newest] Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2020-03-19 22:48 [PATCH linux hwmon-next v1 0/3] Add SB-TSI hwmon driver Kun Yi 2020-03-19 22:48 ` [PATCH linux hwmon-next v1 1/3] hwmon: (sbtsi) Add basic support for SB-TSI sensors Kun Yi 2020-03-19 23:30 ` Guenter Roeck 2020-03-23 23:25 ` Kun Yi 2020-03-19 22:48 ` [PATCH linux hwmon-next v1 2/3] hwmon: (sbtsi) Add documentation Kun Yi 2020-03-19 22:48 ` [PATCH linux hwmon-next v1 3/3] dt-bindings: (hwmon/sbtsi_tmep) Add SB-TSI hwmon driver bindings Kun Yi
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