| Message ID | 1504596848-160952-2-git-send-email-vadimp@mellanox.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
On 09/05/2017 12:34 AM, Vadim Pasternak wrote: > MAX6621 is a PECI-to-I2C translator provides an efficient, low-cost > solution for PECI-to-SMBus/I2C protocol conversion. It allows reading the > temperature from the PECI-compliant host directly from up to four > PECI-enabled CPUs. > > Signed-off-by: Vadim Pasternak <vadimp@mellanox.com> > --- > v2->v3 > Comments pointed out by Guenter: > - arrange includes in alphabetic order; > - use regmap for caching the value of temp_offset to have attribute value > matching hardware value. > - Add to regmap writable, readable, volatile definitions and add cache > initialization to probe; > - have label attribute as RO; > - change if string layout in max6621_verify_reg_data; > - change hwmon_temp_alarm to hwmon_temp_crit_alarm; > - in max6621_read for reading hwmon_temp_crit_alarm set *val to 0 at > beginning of the case statement to recover from the case, when there is > no alert, f.e. reading MAX6621_TEMP_ALERT_CAUSE should result in > MAX6621_ALERT_DIS, which will return error, but alarm should be > returned as 0 in such case; > - clear the alert automatically after reading MAX6621_TEMP_ALERT_CAUSE; > - align clear alert on channels, which report alert temperature. > It requires access to the same register, but will be aligned with > the attribute's definitions; > Fixes added by Vadim: > - change MIN/MAX temperature defaults to -127000/128000; > - add initialization of CONFIG1 register; > v1->v2 > Comments pointed out by Guenter: > - arrange includes in alphabetic order; > - add include for bitops.h; > - remove MAX6621_REG_NON_WRITEABLE_REG; > - drop temp_min, temp_max, temp_reset_history attributes; > - remove redundant braces in max6621_verify_reg_data; > - fix return code in max6621_verify_reg_data; > - not report channels which are not physically connected; > - use u32 for regval in max6621_read and max6621_write; > - provide in temprature offset in milli-degrees C; > - drop hwmon_temp_fault attribute; > - drop activation point setting in CONFIG2 reg, leave it for user space; > Comments pointed out by Jiri: > - fixe device name; > Fixes added by Vadim: > - modify names in max6621_temp_labels; > - add hwmon_temp_alarm attribute and hwmon_temp_crit attributes per > socket; > - fix defines for MIN and MAX temperature; > --- > drivers/hwmon/Kconfig | 14 ++ > drivers/hwmon/Makefile | 1 + > drivers/hwmon/max6621.c | 602 ++++++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 617 insertions(+) > create mode 100644 drivers/hwmon/max6621.c > > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > index 5b9a61f..325d161 100644 > --- a/drivers/hwmon/Kconfig > +++ b/drivers/hwmon/Kconfig > @@ -855,6 +855,20 @@ tristate "MAX31722 temperature sensor" > This driver can also be built as a module. If so, the module > will be called max31722. > > +config SENSORS_MAX6621 > + tristate "Maxim MAX6621 sensor chip" > + depends on I2C > + select REGMAP_I2C > + help > + If you say yes here you get support for MAX6621 sensor chip. > + MAX6621 is a PECI-to-I2C translator provides an efficient, > + low-cost solution for PECI-to-SMBus/I2C protocol conversion. > + It allows reading the temperature from the PECI-compliant > + host directly from up to four PECI-enabled CPUs. > + > + This driver can also be built as a module. If so, the module > + will be called max6621. > + > config SENSORS_MAX6639 > tristate "Maxim MAX6639 sensor chip" > depends on I2C > diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile > index d4641a9..43333cb 100644 > --- a/drivers/hwmon/Makefile > +++ b/drivers/hwmon/Makefile > @@ -116,6 +116,7 @@ obj-$(CONFIG_SENSORS_MAX1619) += max1619.o > obj-$(CONFIG_SENSORS_MAX1668) += max1668.o > obj-$(CONFIG_SENSORS_MAX197) += max197.o > obj-$(CONFIG_SENSORS_MAX31722) += max31722.o > +obj-$(CONFIG_SENSORS_MAX6621) += max6621.o > obj-$(CONFIG_SENSORS_MAX6639) += max6639.o > obj-$(CONFIG_SENSORS_MAX6642) += max6642.o > obj-$(CONFIG_SENSORS_MAX6650) += max6650.o > diff --git a/drivers/hwmon/max6621.c b/drivers/hwmon/max6621.c > new file mode 100644 > index 0000000..7c0122a > --- /dev/null > +++ b/drivers/hwmon/max6621.c > @@ -0,0 +1,602 @@ > +/* > + * Hardware monitoring driver for Maxim MAX6621 > + * > + * Copyright (c) 2017 Mellanox Technologies. All rights reserved. > + * Copyright (c) 2017 Vadim Pasternak <vadimp@mellanox.com> > + * > + * 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. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + */ > + > +#include <linux/bitops.h> > +#include <linux/hwmon.h> > +#include <linux/hwmon-sysfs.h> > +#include <linux/i2c.h> > +#include <linux/init.h> > +#include <linux/module.h> > +#include <linux/of_device.h> > +#include <linux/regmap.h> > + > +#define MAX6621_DRV_NAME "max6621" > +#define MAX6621_TEMP_INPUT_REG_NUM 9 > +#define MAX6621_TEMP_INPUT_MIN -127000 > +#define MAX6621_TEMP_INPUT_MAX 128000 > + > +#define MAX6621_TEMP_S0D0_REG 0x00 > +#define MAX6621_TEMP_S0D1_REG 0x01 > +#define MAX6621_TEMP_S1D0_REG 0x02 > +#define MAX6621_TEMP_S1D1_REG 0x03 > +#define MAX6621_TEMP_S2D0_REG 0x04 > +#define MAX6621_TEMP_S2D1_REG 0x05 > +#define MAX6621_TEMP_S3D0_REG 0x06 > +#define MAX6621_TEMP_S3D1_REG 0x07 > +#define MAX6621_TEMP_MAX_REG 0x08 > +#define MAX6621_TEMP_MAX_ADDR_REG 0x0a > +#define MAX6621_TEMP_ALERT_CAUSE_REG 0x0b > +#define MAX6621_CONFIG0_REG 0x0c > +#define MAX6621_CONFIG1_REG 0x0d > +#define MAX6621_CONFIG2_REG 0x0e > +#define MAX6621_CONFIG3_REG 0x0f > +#define MAX6621_TEMP_S0_ALERT_REG 0x10 > +#define MAX6621_TEMP_S1_ALERT_REG 0x11 > +#define MAX6621_TEMP_S2_ALERT_REG 0x12 > +#define MAX6621_TEMP_S3_ALERT_REG 0x13 > +#define MAX6621_CLEAR_ALERT_REG 0x15 > +#define MAX6621_REG_MAX (MAX6621_CLEAR_ALERT_REG + 1) > +#define MAX6621_REG_TEMP_SHIFT 0x06 > + > +#define MAX6621_ENABLE_TEMP_ALERTS_BIT 4 > +#define MAX6621_ENABLE_I2C_CRC_BIT 5 > +#define MAX6621_ENABLE_ALTERNATE_DATA 6 > +#define MAX6621_ENABLE_LOCKUP_TO 7 > +#define MAX6621_ENABLE_S0D0_BIT 8 > +#define MAX6621_ENABLE_S0D1_BIT 9 > +#define MAX6621_ENABLE_S1D0_BIT 10 > +#define MAX6621_ENABLE_S1D1_BIT 11 > +#define MAX6621_ENABLE_S2D0_BIT 12 > +#define MAX6621_ENABLE_S2D1_BIT 13 > +#define MAX6621_ENABLE_S3D0_BIT 14 > +#define MAX6621_ENABLE_S3D1_BIT 15 Maybe I am missing something, but why not use BIT() here ? I don't see the value in having _BIT in some of the defines (but not all of them). > +#define MAX6621_ENABLE_TEMP_ALL GENMASK(MAX6621_ENABLE_S3D1_BIT, \ > + MAX6621_ENABLE_S0D0_BIT) > +#define MAX6621_POLL_DELAY_MASK 0x5 > +#define MAX6621_CONFIG0_INIT (MAX6621_ENABLE_TEMP_ALL | \ > + BIT(MAX6621_ENABLE_LOCKUP_TO) | \ > + BIT(MAX6621_ENABLE_I2C_CRC_BIT) | \ > + MAX6621_POLL_DELAY_MASK) > +#define MAX6621_PECI_BIT_TIME 0x2 > +#define MAX6621_PECI_RETRY_NUM 0x3 > +#define MAX6621_CONFIG1_INIT ((MAX6621_PECI_BIT_TIME << 8) | \ > + MAX6621_PECI_RETRY_NUM) > + > +/* Error codes */ > +#define MAX6621_TRAN_FAILED 0x8100 /* > + * PECI transaction failed for more > + * than the configured number of > + * consecutive retries. > + */ > +#define MAX6621_POOL_DIS 0x8101 /* > + * Polling disabled for requested > + * socket/domain. > + */ > +#define MAX6621_POOL_UNCOMPLETE 0x8102 /* > + * First poll not yet completed for > + * requested socket/domain (on > + * startup). > + */ > +#define MAX6621_SD_DIS 0x8103 /* > + * Read maximum temperature requested, > + * but no sockets/domains enabled or > + * all enabled sockets/domains have > + * errors; or read maximum temperature > + * address requested, but read maximum > + * temperature was not called. > + */ > +#define MAX6621_ALERT_DIS 0x8104 /* > + * Get alert socket/domain requested, > + * but no alert active. > + */ > +#define MAX6621_PECI_ERR_MIN 0x8000 /* Intel spec PECI error min value. */ > +#define MAX6621_PECI_ERR_MAX 0x80ff /* Intel spec PECI error max value. */ > + > +static const u32 max6621_temp_regs[] = { > + MAX6621_TEMP_MAX_REG, MAX6621_TEMP_S0D0_REG, MAX6621_TEMP_S1D0_REG, > + MAX6621_TEMP_S2D0_REG, MAX6621_TEMP_S3D0_REG, MAX6621_TEMP_S0D1_REG, > + MAX6621_TEMP_S1D1_REG, MAX6621_TEMP_S2D1_REG, MAX6621_TEMP_S3D1_REG, > +}; > + > +static const char *const max6621_temp_labels[] = { > + "maximum", > + "socket0_0", > + "socket1_0", > + "socket2_0", > + "socket3_0", > + "socket0_1", > + "socket1_1", > + "socket2_1", > + "socket3_1", > +}; > + > +static const int max6621_temp_alert_chan2reg[] = { > + MAX6621_CLEAR_ALERT_REG, I still don't understand what this is used for. > + MAX6621_TEMP_S0_ALERT_REG, > + MAX6621_TEMP_S1_ALERT_REG, > + MAX6621_TEMP_S2_ALERT_REG, > + MAX6621_TEMP_S3_ALERT_REG, > +}; > + > +/** > + * struct max6621_data - private data: > + * > + * @client: I2C client; > + * @regmap: register map handle; > + * @input_chan2reg: mapping from channel to register; > + */ > +struct max6621_data { > + struct i2c_client *client; > + struct regmap *regmap; > + int input_chan2reg[MAX6621_TEMP_INPUT_REG_NUM + 1]; > +}; > + > +static long max6621_temp_mc2reg(long val) > +{ > + return (val / 1000L) << MAX6621_REG_TEMP_SHIFT; > +} > + > +static umode_t > +max6621_is_visible(const void *data, enum hwmon_sensor_types type, u32 attr, > + int channel) > +{ > + /* Skip channels which are not physically conncted. */ > + if (((struct max6621_data *)data)->input_chan2reg[channel] < 0) > + return 0; > + > + switch (type) { > + case hwmon_temp: > + switch (attr) { > + case hwmon_temp_input: > + case hwmon_temp_label: > + return 0444; > + case hwmon_temp_offset: > + case hwmon_temp_crit: > + case hwmon_temp_crit_alarm: > + return 0644; > + default: > + break; > + } > + > + default: > + break; > + } > + > + return 0; > +} > + > +static int max6621_verify_reg_data(struct device *dev, int regval) > +{ > + if (regval >= MAX6621_PECI_ERR_MIN && > + regval <= MAX6621_PECI_ERR_MAX) { > + dev_dbg(dev, "PECI error code - err 0x%04x.\n", > + regval); > + > + return -EINVAL; > + } > + > + switch (regval) { > + case MAX6621_TRAN_FAILED: > + dev_dbg(dev, "PECI transaction failed - err 0x%04x.\n", > + regval); > + break; > + case MAX6621_POOL_DIS: > + dev_dbg(dev, "Polling disabled - err 0x%04x.\n", regval); > + break; > + case MAX6621_POOL_UNCOMPLETE: > + dev_dbg(dev, "First poll not completed on startup - err 0x%04x.\n", > + regval); > + break; > + case MAX6621_SD_DIS: > + dev_dbg(dev, "Resource is disabled - err 0x%04x.\n", regval); > + break; > + case MAX6621_ALERT_DIS: > + dev_dbg(dev, "No alert active - err 0x%04x.\n", regval); > + break; > + default: > + return 0; > + } > + > + return -EINVAL; -EINVAL reflects bad user input, which is not the case here. You'll have to find some other error code. > +} > + > +static int > +max6621_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, > + int channel, long *val) > +{ > + struct max6621_data *data = dev_get_drvdata(dev); > + u32 regval; > + int reg; > + s8 temp; > + int ret; > + > + switch (type) { > + case hwmon_temp: > + switch (attr) { > + case hwmon_temp_input: > + reg = data->input_chan2reg[channel]; > + ret = regmap_read(data->regmap, reg, ®val); > + if (ret) > + return ret; > + > + ret = max6621_verify_reg_data(dev, regval); > + if (ret) > + return ret; > + > + /* > + * Bit MAX6621_REG_TEMP_SHIFT represents 1 degree step. > + * The temperature is given in two's complement and 8 > + * bits is used for the register conversion. > + */ > + temp = (regval >> MAX6621_REG_TEMP_SHIFT); > + *val = temp * 1000L; > + > + break; > + case hwmon_temp_offset: > + ret = regmap_read(data->regmap, MAX6621_CONFIG2_REG, > + ®val); > + if (ret) > + return ret; > + > + ret = max6621_verify_reg_data(dev, regval); > + if (ret) > + return ret; > + > + *val = (regval >> MAX6621_REG_TEMP_SHIFT) * > + 1000L; > + > + break; > + case hwmon_temp_crit: > + reg = max6621_temp_alert_chan2reg[channel]; > + ret = regmap_read(data->regmap, reg, ®val); > + if (ret) > + return ret; > + > + ret = max6621_verify_reg_data(dev, regval); > + if (ret) > + return ret; > + > + *val = regval * 1000L; > + > + break; > + case hwmon_temp_crit_alarm: > + /* > + * Set val to zero to recover the case, when reading > + * MAX6621_TEMP_ALERT_CAUSE_REG results in for example > + * MAX6621_ALERT_DIS. Reading will return with error, > + * but in such case alarm should be returned as 0. > + */ > + *val = 0; > + ret = regmap_read(data->regmap, > + MAX6621_TEMP_ALERT_CAUSE_REG, > + ®val); > + if (ret) > + return ret; > + > + ret = max6621_verify_reg_data(dev, regval); > + if (ret < 0) > + return ret; > + max6621_verify_reg_data() will return an error if MAX6621_ALERT_DIS is set. It won't help that *val is set to 0, since reading the attribute will report the error to user space (the read will fail and errno will be set). > + /* > + * Clear the alert automatically, using send-byte > + * smbus protocol for clearing alert. > + */ > + if (regval) { > + ret = i2c_smbus_write_byte(data->client, > + MAX6621_CLEAR_ALERT_REG); > + if (!ret) > + return ret; > + } > + If you are doing this, the writable alarm attribute is unnecessary; reading the attribute accomplishes the same. > + *val = !!regval; > + > + break; > + default: > + return -EOPNOTSUPP; > + } > + break; > + > + default: > + return -EOPNOTSUPP; > + } > + > + return 0; > +} > + > +static int > +max6621_write(struct device *dev, enum hwmon_sensor_types type, u32 attr, > + int channel, long val) > +{ > + struct max6621_data *data = dev_get_drvdata(dev); > + u32 reg; > + > + switch (type) { > + case hwmon_temp: > + switch (attr) { > + case hwmon_temp_offset: > + /* Clamp to allowed range to prevent overflow. */ > + val = clamp_val(val, MAX6621_TEMP_INPUT_MIN, > + MAX6621_TEMP_INPUT_MAX); > + val = max6621_temp_mc2reg(val); > + > + return regmap_write(data->regmap, > + MAX6621_CONFIG2_REG, val); > + case hwmon_temp_crit: > + reg = max6621_temp_alert_chan2reg[channel]; > + /* Clamp to allowed range to prevent overflow. */ > + val = clamp_val(val, MAX6621_TEMP_INPUT_MIN, > + MAX6621_TEMP_INPUT_MAX); > + val = val / 1000L; > + > + return regmap_write(data->regmap, reg, val); > + case hwmon_temp_crit_alarm: > + /* > + * Use i2c_smbus_write_byte, since > + * MAX6621_CLEAR_ALERT_REG access expects send-byte > + * smbus protocol for clearing alert. > + */ > + return i2c_smbus_write_byte(data->client, > + MAX6621_CLEAR_ALERT_REG); > + default: > + return -EOPNOTSUPP; > + } > + break; > + > + default: > + return -EOPNOTSUPP; > + } > + > + return -EOPNOTSUPP; > +} > + > +static int > +max6621_read_string(struct device *dev, enum hwmon_sensor_types type, u32 attr, > + int channel, const char **str) > +{ > + switch (type) { > + case hwmon_temp: > + switch (attr) { > + case hwmon_temp_label: > + *str = max6621_temp_labels[channel]; > + return 0; > + default: > + return -EOPNOTSUPP; > + } > + break; > + default: > + return -EOPNOTSUPP; > + } > + > + return -EOPNOTSUPP; > +} > + > +static bool max6621_writeable_reg(struct device *dev, unsigned int reg) > +{ > + switch (reg) { > + case MAX6621_CONFIG0_REG: > + case MAX6621_CONFIG1_REG: > + case MAX6621_CONFIG2_REG: > + case MAX6621_CONFIG3_REG: > + case MAX6621_TEMP_S0_ALERT_REG: > + case MAX6621_TEMP_S1_ALERT_REG: > + case MAX6621_TEMP_S2_ALERT_REG: > + case MAX6621_TEMP_S3_ALERT_REG: > + case MAX6621_TEMP_ALERT_CAUSE_REG: > + return true; > + } > + return false; > +} > + > +static bool max6621_readable_reg(struct device *dev, unsigned int reg) > +{ > + switch (reg) { > + case MAX6621_TEMP_S0D0_REG: > + case MAX6621_TEMP_S0D1_REG: > + case MAX6621_TEMP_S1D0_REG: > + case MAX6621_TEMP_S1D1_REG: > + case MAX6621_TEMP_S2D0_REG: > + case MAX6621_TEMP_S2D1_REG: > + case MAX6621_TEMP_S3D0_REG: > + case MAX6621_TEMP_S3D1_REG: > + case MAX6621_TEMP_MAX_REG: > + case MAX6621_TEMP_MAX_ADDR_REG: > + case MAX6621_CONFIG0_REG: > + case MAX6621_CONFIG1_REG: > + case MAX6621_CONFIG2_REG: > + case MAX6621_CONFIG3_REG: > + case MAX6621_TEMP_S0_ALERT_REG: > + case MAX6621_TEMP_S1_ALERT_REG: > + case MAX6621_TEMP_S2_ALERT_REG: > + case MAX6621_TEMP_S3_ALERT_REG: > + return true; > + } > + return false; > +} > + > +static bool max6621_volatile_reg(struct device *dev, unsigned int reg) > +{ > + switch (reg) { > + case MAX6621_TEMP_S0D0_REG: > + case MAX6621_TEMP_S0D1_REG: > + case MAX6621_TEMP_S1D0_REG: > + case MAX6621_TEMP_S1D1_REG: > + case MAX6621_TEMP_S2D0_REG: > + case MAX6621_TEMP_S2D1_REG: > + case MAX6621_TEMP_S3D0_REG: > + case MAX6621_TEMP_S3D1_REG: > + case MAX6621_TEMP_MAX_REG: > + case MAX6621_TEMP_S0_ALERT_REG: > + case MAX6621_TEMP_S1_ALERT_REG: > + case MAX6621_TEMP_S2_ALERT_REG: > + case MAX6621_TEMP_S3_ALERT_REG: > + case MAX6621_TEMP_ALERT_CAUSE_REG: > + return true; > + } > + return false; > +} > + > +static const struct reg_default max6621_regmap_default[] = { > + { MAX6621_CONFIG0_REG, MAX6621_CONFIG0_INIT }, > + { MAX6621_CONFIG1_REG, MAX6621_CONFIG1_INIT }, > +}; > + > +static const struct regmap_config max6621_regmap_config = { > + .reg_bits = 8, > + .val_bits = 16, > + .max_register = MAX6621_REG_MAX, > + .val_format_endian = REGMAP_ENDIAN_LITTLE, > + .cache_type = REGCACHE_FLAT, > + .writeable_reg = max6621_writeable_reg, > + .readable_reg = max6621_readable_reg, > + .volatile_reg = max6621_volatile_reg, > + .reg_defaults = max6621_regmap_default, > + .num_reg_defaults = ARRAY_SIZE(max6621_regmap_default), > +}; > + > +static u32 max6621_chip_config[] = { > + HWMON_C_REGISTER_TZ, > + 0 > +}; > + > +static const struct hwmon_channel_info max6621_chip = { > + .type = hwmon_chip, > + .config = max6621_chip_config, > +}; > + > +static const u32 max6621_temp_config[] = { > + HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_OFFSET, > + HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_LABEL, > + HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_LABEL, > + HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_LABEL, > + HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_LABEL, > + HWMON_T_INPUT | HWMON_T_LABEL, > + HWMON_T_INPUT | HWMON_T_LABEL, > + HWMON_T_INPUT | HWMON_T_LABEL, > + HWMON_T_INPUT | HWMON_T_LABEL, > + 0 > +}; > + > +static const struct hwmon_channel_info max6621_temp = { > + .type = hwmon_temp, > + .config = max6621_temp_config, > +}; > + > +static const struct hwmon_channel_info *max6621_info[] = { > + &max6621_chip, > + &max6621_temp, > + NULL > +}; > + > +static const struct hwmon_ops max6621_hwmon_ops = { > + .read = max6621_read, > + .write = max6621_write, > + .read_string = max6621_read_string, > + .is_visible = max6621_is_visible, > +}; > + > +static const struct hwmon_chip_info max6621_chip_info = { > + .ops = &max6621_hwmon_ops, > + .info = max6621_info, > +}; > + > +static int max6621_probe(struct i2c_client *client, > + const struct i2c_device_id *id) > +{ > + struct device *dev = &client->dev; > + struct max6621_data *data; > + struct device *hwmon_dev; > + int i; > + int ret; > + > + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); > + if (!data) > + return -ENOMEM; > + > + data->regmap = devm_regmap_init_i2c(client, &max6621_regmap_config); > + if (IS_ERR(data->regmap)) > + return PTR_ERR(data->regmap); > + > + i2c_set_clientdata(client, data); > + data->client = client; > + > + /* Set CONFIG0 register masking temperature alerts and PEC. */ > + ret = regmap_write(data->regmap, MAX6621_CONFIG0_REG, > + MAX6621_CONFIG0_INIT); > + if (ret) > + return ret; > + > + /* Set CONFIG1 register for PEC access retry number. */ > + ret = regmap_write(data->regmap, MAX6621_CONFIG1_REG, > + MAX6621_CONFIG1_INIT); > + if (ret) > + return ret; > + > + /* Sync registers with hardware. */ > + regcache_mark_dirty(data->regmap); > + ret = regcache_sync(data->regmap); > + if (ret) > + return ret; > + > + /* Verify which temperature input registers are enabled. */ > + for (i = 0; i < MAX6621_TEMP_INPUT_REG_NUM; i++) { > + ret = i2c_smbus_read_word_data(client, max6621_temp_regs[i]); > + if (ret < 0) > + return ret; > + ret = max6621_verify_reg_data(dev, ret); > + if (ret) { > + data->input_chan2reg[i] = -1; > + continue; > + } > + > + data->input_chan2reg[i] = max6621_temp_regs[i]; > + } > + > + hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, > + data, > + &max6621_chip_info, > + NULL); > + > + return PTR_ERR_OR_ZERO(hwmon_dev); > +} > + > +static const struct i2c_device_id max6621_id[] = { > + { MAX6621_DRV_NAME, 0 }, > + { } > +}; > +MODULE_DEVICE_TABLE(i2c, max6621_id); > + > +static const struct of_device_id max6621_of_match[] = { > + { .compatible = "maxim,max6621" }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, max6621_of_match); > + > +static struct i2c_driver max6621_driver = { > + .class = I2C_CLASS_HWMON, > + .driver = { > + .name = MAX6621_DRV_NAME, > + .of_match_table = of_match_ptr(max6621_of_match), > + }, > + .probe = max6621_probe, > + .id_table = max6621_id, > +}; > + > +module_i2c_driver(max6621_driver); > + > +MODULE_AUTHOR("Vadim Pasternak <vadimp@mellanox.com>"); > +MODULE_DESCRIPTION("Driver for Maxim MAX6621"); > +MODULE_LICENSE("GPL"); > -- To unsubscribe from this list: send the line "unsubscribe linux-hwmon" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 5b9a61f..325d161 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -855,6 +855,20 @@ tristate "MAX31722 temperature sensor" This driver can also be built as a module. If so, the module will be called max31722. +config SENSORS_MAX6621 + tristate "Maxim MAX6621 sensor chip" + depends on I2C + select REGMAP_I2C + help + If you say yes here you get support for MAX6621 sensor chip. + MAX6621 is a PECI-to-I2C translator provides an efficient, + low-cost solution for PECI-to-SMBus/I2C protocol conversion. + It allows reading the temperature from the PECI-compliant + host directly from up to four PECI-enabled CPUs. + + This driver can also be built as a module. If so, the module + will be called max6621. + config SENSORS_MAX6639 tristate "Maxim MAX6639 sensor chip" depends on I2C diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index d4641a9..43333cb 100644 --- a/drivers/hwmon/Makefile +++ b/drivers/hwmon/Makefile @@ -116,6 +116,7 @@ obj-$(CONFIG_SENSORS_MAX1619) += max1619.o obj-$(CONFIG_SENSORS_MAX1668) += max1668.o obj-$(CONFIG_SENSORS_MAX197) += max197.o obj-$(CONFIG_SENSORS_MAX31722) += max31722.o +obj-$(CONFIG_SENSORS_MAX6621) += max6621.o obj-$(CONFIG_SENSORS_MAX6639) += max6639.o obj-$(CONFIG_SENSORS_MAX6642) += max6642.o obj-$(CONFIG_SENSORS_MAX6650) += max6650.o diff --git a/drivers/hwmon/max6621.c b/drivers/hwmon/max6621.c new file mode 100644 index 0000000..7c0122a --- /dev/null +++ b/drivers/hwmon/max6621.c @@ -0,0 +1,602 @@ +/* + * Hardware monitoring driver for Maxim MAX6621 + * + * Copyright (c) 2017 Mellanox Technologies. All rights reserved. + * Copyright (c) 2017 Vadim Pasternak <vadimp@mellanox.com> + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/bitops.h> +#include <linux/hwmon.h> +#include <linux/hwmon-sysfs.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/regmap.h> + +#define MAX6621_DRV_NAME "max6621" +#define MAX6621_TEMP_INPUT_REG_NUM 9 +#define MAX6621_TEMP_INPUT_MIN -127000 +#define MAX6621_TEMP_INPUT_MAX 128000 + +#define MAX6621_TEMP_S0D0_REG 0x00 +#define MAX6621_TEMP_S0D1_REG 0x01 +#define MAX6621_TEMP_S1D0_REG 0x02 +#define MAX6621_TEMP_S1D1_REG 0x03 +#define MAX6621_TEMP_S2D0_REG 0x04 +#define MAX6621_TEMP_S2D1_REG 0x05 +#define MAX6621_TEMP_S3D0_REG 0x06 +#define MAX6621_TEMP_S3D1_REG 0x07 +#define MAX6621_TEMP_MAX_REG 0x08 +#define MAX6621_TEMP_MAX_ADDR_REG 0x0a +#define MAX6621_TEMP_ALERT_CAUSE_REG 0x0b +#define MAX6621_CONFIG0_REG 0x0c +#define MAX6621_CONFIG1_REG 0x0d +#define MAX6621_CONFIG2_REG 0x0e +#define MAX6621_CONFIG3_REG 0x0f +#define MAX6621_TEMP_S0_ALERT_REG 0x10 +#define MAX6621_TEMP_S1_ALERT_REG 0x11 +#define MAX6621_TEMP_S2_ALERT_REG 0x12 +#define MAX6621_TEMP_S3_ALERT_REG 0x13 +#define MAX6621_CLEAR_ALERT_REG 0x15 +#define MAX6621_REG_MAX (MAX6621_CLEAR_ALERT_REG + 1) +#define MAX6621_REG_TEMP_SHIFT 0x06 + +#define MAX6621_ENABLE_TEMP_ALERTS_BIT 4 +#define MAX6621_ENABLE_I2C_CRC_BIT 5 +#define MAX6621_ENABLE_ALTERNATE_DATA 6 +#define MAX6621_ENABLE_LOCKUP_TO 7 +#define MAX6621_ENABLE_S0D0_BIT 8 +#define MAX6621_ENABLE_S0D1_BIT 9 +#define MAX6621_ENABLE_S1D0_BIT 10 +#define MAX6621_ENABLE_S1D1_BIT 11 +#define MAX6621_ENABLE_S2D0_BIT 12 +#define MAX6621_ENABLE_S2D1_BIT 13 +#define MAX6621_ENABLE_S3D0_BIT 14 +#define MAX6621_ENABLE_S3D1_BIT 15 +#define MAX6621_ENABLE_TEMP_ALL GENMASK(MAX6621_ENABLE_S3D1_BIT, \ + MAX6621_ENABLE_S0D0_BIT) +#define MAX6621_POLL_DELAY_MASK 0x5 +#define MAX6621_CONFIG0_INIT (MAX6621_ENABLE_TEMP_ALL | \ + BIT(MAX6621_ENABLE_LOCKUP_TO) | \ + BIT(MAX6621_ENABLE_I2C_CRC_BIT) | \ + MAX6621_POLL_DELAY_MASK) +#define MAX6621_PECI_BIT_TIME 0x2 +#define MAX6621_PECI_RETRY_NUM 0x3 +#define MAX6621_CONFIG1_INIT ((MAX6621_PECI_BIT_TIME << 8) | \ + MAX6621_PECI_RETRY_NUM) + +/* Error codes */ +#define MAX6621_TRAN_FAILED 0x8100 /* + * PECI transaction failed for more + * than the configured number of + * consecutive retries. + */ +#define MAX6621_POOL_DIS 0x8101 /* + * Polling disabled for requested + * socket/domain. + */ +#define MAX6621_POOL_UNCOMPLETE 0x8102 /* + * First poll not yet completed for + * requested socket/domain (on + * startup). + */ +#define MAX6621_SD_DIS 0x8103 /* + * Read maximum temperature requested, + * but no sockets/domains enabled or + * all enabled sockets/domains have + * errors; or read maximum temperature + * address requested, but read maximum + * temperature was not called. + */ +#define MAX6621_ALERT_DIS 0x8104 /* + * Get alert socket/domain requested, + * but no alert active. + */ +#define MAX6621_PECI_ERR_MIN 0x8000 /* Intel spec PECI error min value. */ +#define MAX6621_PECI_ERR_MAX 0x80ff /* Intel spec PECI error max value. */ + +static const u32 max6621_temp_regs[] = { + MAX6621_TEMP_MAX_REG, MAX6621_TEMP_S0D0_REG, MAX6621_TEMP_S1D0_REG, + MAX6621_TEMP_S2D0_REG, MAX6621_TEMP_S3D0_REG, MAX6621_TEMP_S0D1_REG, + MAX6621_TEMP_S1D1_REG, MAX6621_TEMP_S2D1_REG, MAX6621_TEMP_S3D1_REG, +}; + +static const char *const max6621_temp_labels[] = { + "maximum", + "socket0_0", + "socket1_0", + "socket2_0", + "socket3_0", + "socket0_1", + "socket1_1", + "socket2_1", + "socket3_1", +}; + +static const int max6621_temp_alert_chan2reg[] = { + MAX6621_CLEAR_ALERT_REG, + MAX6621_TEMP_S0_ALERT_REG, + MAX6621_TEMP_S1_ALERT_REG, + MAX6621_TEMP_S2_ALERT_REG, + MAX6621_TEMP_S3_ALERT_REG, +}; + +/** + * struct max6621_data - private data: + * + * @client: I2C client; + * @regmap: register map handle; + * @input_chan2reg: mapping from channel to register; + */ +struct max6621_data { + struct i2c_client *client; + struct regmap *regmap; + int input_chan2reg[MAX6621_TEMP_INPUT_REG_NUM + 1]; +}; + +static long max6621_temp_mc2reg(long val) +{ + return (val / 1000L) << MAX6621_REG_TEMP_SHIFT; +} + +static umode_t +max6621_is_visible(const void *data, enum hwmon_sensor_types type, u32 attr, + int channel) +{ + /* Skip channels which are not physically conncted. */ + if (((struct max6621_data *)data)->input_chan2reg[channel] < 0) + return 0; + + switch (type) { + case hwmon_temp: + switch (attr) { + case hwmon_temp_input: + case hwmon_temp_label: + return 0444; + case hwmon_temp_offset: + case hwmon_temp_crit: + case hwmon_temp_crit_alarm: + return 0644; + default: + break; + } + + default: + break; + } + + return 0; +} + +static int max6621_verify_reg_data(struct device *dev, int regval) +{ + if (regval >= MAX6621_PECI_ERR_MIN && + regval <= MAX6621_PECI_ERR_MAX) { + dev_dbg(dev, "PECI error code - err 0x%04x.\n", + regval); + + return -EINVAL; + } + + switch (regval) { + case MAX6621_TRAN_FAILED: + dev_dbg(dev, "PECI transaction failed - err 0x%04x.\n", + regval); + break; + case MAX6621_POOL_DIS: + dev_dbg(dev, "Polling disabled - err 0x%04x.\n", regval); + break; + case MAX6621_POOL_UNCOMPLETE: + dev_dbg(dev, "First poll not completed on startup - err 0x%04x.\n", + regval); + break; + case MAX6621_SD_DIS: + dev_dbg(dev, "Resource is disabled - err 0x%04x.\n", regval); + break; + case MAX6621_ALERT_DIS: + dev_dbg(dev, "No alert active - err 0x%04x.\n", regval); + break; + default: + return 0; + } + + return -EINVAL; +} + +static int +max6621_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, + int channel, long *val) +{ + struct max6621_data *data = dev_get_drvdata(dev); + u32 regval; + int reg; + s8 temp; + int ret; + + switch (type) { + case hwmon_temp: + switch (attr) { + case hwmon_temp_input: + reg = data->input_chan2reg[channel]; + ret = regmap_read(data->regmap, reg, ®val); + if (ret) + return ret; + + ret = max6621_verify_reg_data(dev, regval); + if (ret) + return ret; + + /* + * Bit MAX6621_REG_TEMP_SHIFT represents 1 degree step. + * The temperature is given in two's complement and 8 + * bits is used for the register conversion. + */ + temp = (regval >> MAX6621_REG_TEMP_SHIFT); + *val = temp * 1000L; + + break; + case hwmon_temp_offset: + ret = regmap_read(data->regmap, MAX6621_CONFIG2_REG, + ®val); + if (ret) + return ret; + + ret = max6621_verify_reg_data(dev, regval); + if (ret) + return ret; + + *val = (regval >> MAX6621_REG_TEMP_SHIFT) * + 1000L; + + break; + case hwmon_temp_crit: + reg = max6621_temp_alert_chan2reg[channel]; + ret = regmap_read(data->regmap, reg, ®val); + if (ret) + return ret; + + ret = max6621_verify_reg_data(dev, regval); + if (ret) + return ret; + + *val = regval * 1000L; + + break; + case hwmon_temp_crit_alarm: + /* + * Set val to zero to recover the case, when reading + * MAX6621_TEMP_ALERT_CAUSE_REG results in for example + * MAX6621_ALERT_DIS. Reading will return with error, + * but in such case alarm should be returned as 0. + */ + *val = 0; + ret = regmap_read(data->regmap, + MAX6621_TEMP_ALERT_CAUSE_REG, + ®val); + if (ret) + return ret; + + ret = max6621_verify_reg_data(dev, regval); + if (ret < 0) + return ret; + + /* + * Clear the alert automatically, using send-byte + * smbus protocol for clearing alert. + */ + if (regval) { + ret = i2c_smbus_write_byte(data->client, + MAX6621_CLEAR_ALERT_REG); + if (!ret) + return ret; + } + + *val = !!regval; + + break; + default: + return -EOPNOTSUPP; + } + break; + + default: + return -EOPNOTSUPP; + } + + return 0; +} + +static int +max6621_write(struct device *dev, enum hwmon_sensor_types type, u32 attr, + int channel, long val) +{ + struct max6621_data *data = dev_get_drvdata(dev); + u32 reg; + + switch (type) { + case hwmon_temp: + switch (attr) { + case hwmon_temp_offset: + /* Clamp to allowed range to prevent overflow. */ + val = clamp_val(val, MAX6621_TEMP_INPUT_MIN, + MAX6621_TEMP_INPUT_MAX); + val = max6621_temp_mc2reg(val); + + return regmap_write(data->regmap, + MAX6621_CONFIG2_REG, val); + case hwmon_temp_crit: + reg = max6621_temp_alert_chan2reg[channel]; + /* Clamp to allowed range to prevent overflow. */ + val = clamp_val(val, MAX6621_TEMP_INPUT_MIN, + MAX6621_TEMP_INPUT_MAX); + val = val / 1000L; + + return regmap_write(data->regmap, reg, val); + case hwmon_temp_crit_alarm: + /* + * Use i2c_smbus_write_byte, since + * MAX6621_CLEAR_ALERT_REG access expects send-byte + * smbus protocol for clearing alert. + */ + return i2c_smbus_write_byte(data->client, + MAX6621_CLEAR_ALERT_REG); + default: + return -EOPNOTSUPP; + } + break; + + default: + return -EOPNOTSUPP; + } + + return -EOPNOTSUPP; +} + +static int +max6621_read_string(struct device *dev, enum hwmon_sensor_types type, u32 attr, + int channel, const char **str) +{ + switch (type) { + case hwmon_temp: + switch (attr) { + case hwmon_temp_label: + *str = max6621_temp_labels[channel]; + return 0; + default: + return -EOPNOTSUPP; + } + break; + default: + return -EOPNOTSUPP; + } + + return -EOPNOTSUPP; +} + +static bool max6621_writeable_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case MAX6621_CONFIG0_REG: + case MAX6621_CONFIG1_REG: + case MAX6621_CONFIG2_REG: + case MAX6621_CONFIG3_REG: + case MAX6621_TEMP_S0_ALERT_REG: + case MAX6621_TEMP_S1_ALERT_REG: + case MAX6621_TEMP_S2_ALERT_REG: + case MAX6621_TEMP_S3_ALERT_REG: + case MAX6621_TEMP_ALERT_CAUSE_REG: + return true; + } + return false; +} + +static bool max6621_readable_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case MAX6621_TEMP_S0D0_REG: + case MAX6621_TEMP_S0D1_REG: + case MAX6621_TEMP_S1D0_REG: + case MAX6621_TEMP_S1D1_REG: + case MAX6621_TEMP_S2D0_REG: + case MAX6621_TEMP_S2D1_REG: + case MAX6621_TEMP_S3D0_REG: + case MAX6621_TEMP_S3D1_REG: + case MAX6621_TEMP_MAX_REG: + case MAX6621_TEMP_MAX_ADDR_REG: + case MAX6621_CONFIG0_REG: + case MAX6621_CONFIG1_REG: + case MAX6621_CONFIG2_REG: + case MAX6621_CONFIG3_REG: + case MAX6621_TEMP_S0_ALERT_REG: + case MAX6621_TEMP_S1_ALERT_REG: + case MAX6621_TEMP_S2_ALERT_REG: + case MAX6621_TEMP_S3_ALERT_REG: + return true; + } + return false; +} + +static bool max6621_volatile_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case MAX6621_TEMP_S0D0_REG: + case MAX6621_TEMP_S0D1_REG: + case MAX6621_TEMP_S1D0_REG: + case MAX6621_TEMP_S1D1_REG: + case MAX6621_TEMP_S2D0_REG: + case MAX6621_TEMP_S2D1_REG: + case MAX6621_TEMP_S3D0_REG: + case MAX6621_TEMP_S3D1_REG: + case MAX6621_TEMP_MAX_REG: + case MAX6621_TEMP_S0_ALERT_REG: + case MAX6621_TEMP_S1_ALERT_REG: + case MAX6621_TEMP_S2_ALERT_REG: + case MAX6621_TEMP_S3_ALERT_REG: + case MAX6621_TEMP_ALERT_CAUSE_REG: + return true; + } + return false; +} + +static const struct reg_default max6621_regmap_default[] = { + { MAX6621_CONFIG0_REG, MAX6621_CONFIG0_INIT }, + { MAX6621_CONFIG1_REG, MAX6621_CONFIG1_INIT }, +}; + +static const struct regmap_config max6621_regmap_config = { + .reg_bits = 8, + .val_bits = 16, + .max_register = MAX6621_REG_MAX, + .val_format_endian = REGMAP_ENDIAN_LITTLE, + .cache_type = REGCACHE_FLAT, + .writeable_reg = max6621_writeable_reg, + .readable_reg = max6621_readable_reg, + .volatile_reg = max6621_volatile_reg, + .reg_defaults = max6621_regmap_default, + .num_reg_defaults = ARRAY_SIZE(max6621_regmap_default), +}; + +static u32 max6621_chip_config[] = { + HWMON_C_REGISTER_TZ, + 0 +}; + +static const struct hwmon_channel_info max6621_chip = { + .type = hwmon_chip, + .config = max6621_chip_config, +}; + +static const u32 max6621_temp_config[] = { + HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_OFFSET, + HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_LABEL, + 0 +}; + +static const struct hwmon_channel_info max6621_temp = { + .type = hwmon_temp, + .config = max6621_temp_config, +}; + +static const struct hwmon_channel_info *max6621_info[] = { + &max6621_chip, + &max6621_temp, + NULL +}; + +static const struct hwmon_ops max6621_hwmon_ops = { + .read = max6621_read, + .write = max6621_write, + .read_string = max6621_read_string, + .is_visible = max6621_is_visible, +}; + +static const struct hwmon_chip_info max6621_chip_info = { + .ops = &max6621_hwmon_ops, + .info = max6621_info, +}; + +static int max6621_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct device *dev = &client->dev; + struct max6621_data *data; + struct device *hwmon_dev; + int i; + int ret; + + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->regmap = devm_regmap_init_i2c(client, &max6621_regmap_config); + if (IS_ERR(data->regmap)) + return PTR_ERR(data->regmap); + + i2c_set_clientdata(client, data); + data->client = client; + + /* Set CONFIG0 register masking temperature alerts and PEC. */ + ret = regmap_write(data->regmap, MAX6621_CONFIG0_REG, + MAX6621_CONFIG0_INIT); + if (ret) + return ret; + + /* Set CONFIG1 register for PEC access retry number. */ + ret = regmap_write(data->regmap, MAX6621_CONFIG1_REG, + MAX6621_CONFIG1_INIT); + if (ret) + return ret; + + /* Sync registers with hardware. */ + regcache_mark_dirty(data->regmap); + ret = regcache_sync(data->regmap); + if (ret) + return ret; + + /* Verify which temperature input registers are enabled. */ + for (i = 0; i < MAX6621_TEMP_INPUT_REG_NUM; i++) { + ret = i2c_smbus_read_word_data(client, max6621_temp_regs[i]); + if (ret < 0) + return ret; + ret = max6621_verify_reg_data(dev, ret); + if (ret) { + data->input_chan2reg[i] = -1; + continue; + } + + data->input_chan2reg[i] = max6621_temp_regs[i]; + } + + hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, + data, + &max6621_chip_info, + NULL); + + return PTR_ERR_OR_ZERO(hwmon_dev); +} + +static const struct i2c_device_id max6621_id[] = { + { MAX6621_DRV_NAME, 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, max6621_id); + +static const struct of_device_id max6621_of_match[] = { + { .compatible = "maxim,max6621" }, + { } +}; +MODULE_DEVICE_TABLE(of, max6621_of_match); + +static struct i2c_driver max6621_driver = { + .class = I2C_CLASS_HWMON, + .driver = { + .name = MAX6621_DRV_NAME, + .of_match_table = of_match_ptr(max6621_of_match), + }, + .probe = max6621_probe, + .id_table = max6621_id, +}; + +module_i2c_driver(max6621_driver); + +MODULE_AUTHOR("Vadim Pasternak <vadimp@mellanox.com>"); +MODULE_DESCRIPTION("Driver for Maxim MAX6621"); +MODULE_LICENSE("GPL");
MAX6621 is a PECI-to-I2C translator provides an efficient, low-cost solution for PECI-to-SMBus/I2C protocol conversion. It allows reading the temperature from the PECI-compliant host directly from up to four PECI-enabled CPUs. Signed-off-by: Vadim Pasternak <vadimp@mellanox.com> --- v2->v3 Comments pointed out by Guenter: - arrange includes in alphabetic order; - use regmap for caching the value of temp_offset to have attribute value matching hardware value. - Add to regmap writable, readable, volatile definitions and add cache initialization to probe; - have label attribute as RO; - change if string layout in max6621_verify_reg_data; - change hwmon_temp_alarm to hwmon_temp_crit_alarm; - in max6621_read for reading hwmon_temp_crit_alarm set *val to 0 at beginning of the case statement to recover from the case, when there is no alert, f.e. reading MAX6621_TEMP_ALERT_CAUSE should result in MAX6621_ALERT_DIS, which will return error, but alarm should be returned as 0 in such case; - clear the alert automatically after reading MAX6621_TEMP_ALERT_CAUSE; - align clear alert on channels, which report alert temperature. It requires access to the same register, but will be aligned with the attribute's definitions; Fixes added by Vadim: - change MIN/MAX temperature defaults to -127000/128000; - add initialization of CONFIG1 register; v1->v2 Comments pointed out by Guenter: - arrange includes in alphabetic order; - add include for bitops.h; - remove MAX6621_REG_NON_WRITEABLE_REG; - drop temp_min, temp_max, temp_reset_history attributes; - remove redundant braces in max6621_verify_reg_data; - fix return code in max6621_verify_reg_data; - not report channels which are not physically connected; - use u32 for regval in max6621_read and max6621_write; - provide in temprature offset in milli-degrees C; - drop hwmon_temp_fault attribute; - drop activation point setting in CONFIG2 reg, leave it for user space; Comments pointed out by Jiri: - fixe device name; Fixes added by Vadim: - modify names in max6621_temp_labels; - add hwmon_temp_alarm attribute and hwmon_temp_crit attributes per socket; - fix defines for MIN and MAX temperature; --- drivers/hwmon/Kconfig | 14 ++ drivers/hwmon/Makefile | 1 + drivers/hwmon/max6621.c | 602 ++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 617 insertions(+) create mode 100644 drivers/hwmon/max6621.c