diff options
Diffstat (limited to 'drivers/hwmon/jc42.c')
| -rw-r--r-- | drivers/hwmon/jc42.c | 643 |
1 files changed, 643 insertions, 0 deletions
diff --git a/drivers/hwmon/jc42.c b/drivers/hwmon/jc42.c new file mode 100644 index 000000000..6593d81cb --- /dev/null +++ b/drivers/hwmon/jc42.c @@ -0,0 +1,643 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * jc42.c - driver for Jedec JC42.4 compliant temperature sensors + * + * Copyright (c) 2010 Ericsson AB. + * + * Derived from lm77.c by Andras BALI <drewie@freemail.hu>. + * + * JC42.4 compliant temperature sensors are typically used on memory modules. + */ + +#include <linux/bitops.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/jiffies.h> +#include <linux/i2c.h> +#include <linux/hwmon.h> +#include <linux/err.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/regmap.h> + +/* Addresses to scan */ +static const unsigned short normal_i2c[] = { + 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, I2C_CLIENT_END }; + +/* JC42 registers. All registers are 16 bit. */ +#define JC42_REG_CAP 0x00 +#define JC42_REG_CONFIG 0x01 +#define JC42_REG_TEMP_UPPER 0x02 +#define JC42_REG_TEMP_LOWER 0x03 +#define JC42_REG_TEMP_CRITICAL 0x04 +#define JC42_REG_TEMP 0x05 +#define JC42_REG_MANID 0x06 +#define JC42_REG_DEVICEID 0x07 +#define JC42_REG_SMBUS 0x22 /* NXP and Atmel, possibly others? */ + +/* Status bits in temperature register */ +#define JC42_ALARM_CRIT_BIT 15 +#define JC42_ALARM_MAX_BIT 14 +#define JC42_ALARM_MIN_BIT 13 + +/* Configuration register defines */ +#define JC42_CFG_CRIT_ONLY (1 << 2) +#define JC42_CFG_TCRIT_LOCK (1 << 6) +#define JC42_CFG_EVENT_LOCK (1 << 7) +#define JC42_CFG_SHUTDOWN (1 << 8) +#define JC42_CFG_HYST_SHIFT 9 +#define JC42_CFG_HYST_MASK (0x03 << 9) + +/* Capabilities */ +#define JC42_CAP_RANGE (1 << 2) + +/* Manufacturer IDs */ +#define ADT_MANID 0x11d4 /* Analog Devices */ +#define ATMEL_MANID 0x001f /* Atmel */ +#define ATMEL_MANID2 0x1114 /* Atmel */ +#define MAX_MANID 0x004d /* Maxim */ +#define IDT_MANID 0x00b3 /* IDT */ +#define MCP_MANID 0x0054 /* Microchip */ +#define NXP_MANID 0x1131 /* NXP Semiconductors */ +#define ONS_MANID 0x1b09 /* ON Semiconductor */ +#define STM_MANID 0x104a /* ST Microelectronics */ +#define GT_MANID 0x1c68 /* Giantec */ +#define GT_MANID2 0x132d /* Giantec, 2nd mfg ID */ +#define SI_MANID 0x1c85 /* Seiko Instruments */ + +/* SMBUS register */ +#define SMBUS_STMOUT BIT(7) /* SMBus time-out, active low */ + +/* Supported chips */ + +/* Analog Devices */ +#define ADT7408_DEVID 0x0801 +#define ADT7408_DEVID_MASK 0xffff + +/* Atmel */ +#define AT30TS00_DEVID 0x8201 +#define AT30TS00_DEVID_MASK 0xffff + +#define AT30TSE004_DEVID 0x2200 +#define AT30TSE004_DEVID_MASK 0xffff + +/* Giantec */ +#define GT30TS00_DEVID 0x2200 +#define GT30TS00_DEVID_MASK 0xff00 + +#define GT34TS02_DEVID 0x3300 +#define GT34TS02_DEVID_MASK 0xff00 + +/* IDT */ +#define TSE2004_DEVID 0x2200 +#define TSE2004_DEVID_MASK 0xff00 + +#define TS3000_DEVID 0x2900 /* Also matches TSE2002 */ +#define TS3000_DEVID_MASK 0xff00 + +#define TS3001_DEVID 0x3000 +#define TS3001_DEVID_MASK 0xff00 + +/* Maxim */ +#define MAX6604_DEVID 0x3e00 +#define MAX6604_DEVID_MASK 0xffff + +/* Microchip */ +#define MCP9804_DEVID 0x0200 +#define MCP9804_DEVID_MASK 0xfffc + +#define MCP9808_DEVID 0x0400 +#define MCP9808_DEVID_MASK 0xfffc + +#define MCP98242_DEVID 0x2000 +#define MCP98242_DEVID_MASK 0xfffc + +#define MCP98243_DEVID 0x2100 +#define MCP98243_DEVID_MASK 0xfffc + +#define MCP98244_DEVID 0x2200 +#define MCP98244_DEVID_MASK 0xfffc + +#define MCP9843_DEVID 0x0000 /* Also matches mcp9805 */ +#define MCP9843_DEVID_MASK 0xfffe + +/* NXP */ +#define SE97_DEVID 0xa200 +#define SE97_DEVID_MASK 0xfffc + +#define SE98_DEVID 0xa100 +#define SE98_DEVID_MASK 0xfffc + +/* ON Semiconductor */ +#define CAT6095_DEVID 0x0800 /* Also matches CAT34TS02 */ +#define CAT6095_DEVID_MASK 0xffe0 + +#define CAT34TS02C_DEVID 0x0a00 +#define CAT34TS02C_DEVID_MASK 0xfff0 + +#define CAT34TS04_DEVID 0x2200 +#define CAT34TS04_DEVID_MASK 0xfff0 + +#define N34TS04_DEVID 0x2230 +#define N34TS04_DEVID_MASK 0xfff0 + +/* ST Microelectronics */ +#define STTS424_DEVID 0x0101 +#define STTS424_DEVID_MASK 0xffff + +#define STTS424E_DEVID 0x0000 +#define STTS424E_DEVID_MASK 0xfffe + +#define STTS2002_DEVID 0x0300 +#define STTS2002_DEVID_MASK 0xffff + +#define STTS2004_DEVID 0x2201 +#define STTS2004_DEVID_MASK 0xffff + +#define STTS3000_DEVID 0x0200 +#define STTS3000_DEVID_MASK 0xffff + +/* Seiko Instruments */ +#define S34TS04A_DEVID 0x2221 +#define S34TS04A_DEVID_MASK 0xffff + +static u16 jc42_hysteresis[] = { 0, 1500, 3000, 6000 }; + +struct jc42_chips { + u16 manid; + u16 devid; + u16 devid_mask; +}; + +static struct jc42_chips jc42_chips[] = { + { ADT_MANID, ADT7408_DEVID, ADT7408_DEVID_MASK }, + { ATMEL_MANID, AT30TS00_DEVID, AT30TS00_DEVID_MASK }, + { ATMEL_MANID2, AT30TSE004_DEVID, AT30TSE004_DEVID_MASK }, + { GT_MANID, GT30TS00_DEVID, GT30TS00_DEVID_MASK }, + { GT_MANID2, GT34TS02_DEVID, GT34TS02_DEVID_MASK }, + { IDT_MANID, TSE2004_DEVID, TSE2004_DEVID_MASK }, + { IDT_MANID, TS3000_DEVID, TS3000_DEVID_MASK }, + { IDT_MANID, TS3001_DEVID, TS3001_DEVID_MASK }, + { MAX_MANID, MAX6604_DEVID, MAX6604_DEVID_MASK }, + { MCP_MANID, MCP9804_DEVID, MCP9804_DEVID_MASK }, + { MCP_MANID, MCP9808_DEVID, MCP9808_DEVID_MASK }, + { MCP_MANID, MCP98242_DEVID, MCP98242_DEVID_MASK }, + { MCP_MANID, MCP98243_DEVID, MCP98243_DEVID_MASK }, + { MCP_MANID, MCP98244_DEVID, MCP98244_DEVID_MASK }, + { MCP_MANID, MCP9843_DEVID, MCP9843_DEVID_MASK }, + { NXP_MANID, SE97_DEVID, SE97_DEVID_MASK }, + { ONS_MANID, CAT6095_DEVID, CAT6095_DEVID_MASK }, + { ONS_MANID, CAT34TS02C_DEVID, CAT34TS02C_DEVID_MASK }, + { ONS_MANID, CAT34TS04_DEVID, CAT34TS04_DEVID_MASK }, + { ONS_MANID, N34TS04_DEVID, N34TS04_DEVID_MASK }, + { NXP_MANID, SE98_DEVID, SE98_DEVID_MASK }, + { SI_MANID, S34TS04A_DEVID, S34TS04A_DEVID_MASK }, + { STM_MANID, STTS424_DEVID, STTS424_DEVID_MASK }, + { STM_MANID, STTS424E_DEVID, STTS424E_DEVID_MASK }, + { STM_MANID, STTS2002_DEVID, STTS2002_DEVID_MASK }, + { STM_MANID, STTS2004_DEVID, STTS2004_DEVID_MASK }, + { STM_MANID, STTS3000_DEVID, STTS3000_DEVID_MASK }, +}; + +/* Each client has this additional data */ +struct jc42_data { + struct mutex update_lock; /* protect register access */ + struct regmap *regmap; + bool extended; /* true if extended range supported */ + bool valid; + u16 orig_config; /* original configuration */ + u16 config; /* current configuration */ +}; + +#define JC42_TEMP_MIN_EXTENDED (-40000) +#define JC42_TEMP_MIN 0 +#define JC42_TEMP_MAX 125000 + +static u16 jc42_temp_to_reg(long temp, bool extended) +{ + int ntemp = clamp_val(temp, + extended ? JC42_TEMP_MIN_EXTENDED : + JC42_TEMP_MIN, JC42_TEMP_MAX); + + /* convert from 0.001 to 0.0625 resolution */ + return (ntemp * 2 / 125) & 0x1fff; +} + +static int jc42_temp_from_reg(s16 reg) +{ + reg = sign_extend32(reg, 12); + + /* convert from 0.0625 to 0.001 resolution */ + return reg * 125 / 2; +} + +static int jc42_read(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long *val) +{ + struct jc42_data *data = dev_get_drvdata(dev); + unsigned int regval; + int ret, temp, hyst; + + mutex_lock(&data->update_lock); + + switch (attr) { + case hwmon_temp_input: + ret = regmap_read(data->regmap, JC42_REG_TEMP, ®val); + if (ret) + break; + + *val = jc42_temp_from_reg(regval); + break; + case hwmon_temp_min: + ret = regmap_read(data->regmap, JC42_REG_TEMP_LOWER, ®val); + if (ret) + break; + + *val = jc42_temp_from_reg(regval); + break; + case hwmon_temp_max: + ret = regmap_read(data->regmap, JC42_REG_TEMP_UPPER, ®val); + if (ret) + break; + + *val = jc42_temp_from_reg(regval); + break; + case hwmon_temp_crit: + ret = regmap_read(data->regmap, JC42_REG_TEMP_CRITICAL, + ®val); + if (ret) + break; + + *val = jc42_temp_from_reg(regval); + break; + case hwmon_temp_max_hyst: + ret = regmap_read(data->regmap, JC42_REG_TEMP_UPPER, ®val); + if (ret) + break; + + temp = jc42_temp_from_reg(regval); + hyst = jc42_hysteresis[(data->config & JC42_CFG_HYST_MASK) + >> JC42_CFG_HYST_SHIFT]; + *val = temp - hyst; + break; + case hwmon_temp_crit_hyst: + ret = regmap_read(data->regmap, JC42_REG_TEMP_CRITICAL, + ®val); + if (ret) + break; + + temp = jc42_temp_from_reg(regval); + hyst = jc42_hysteresis[(data->config & JC42_CFG_HYST_MASK) + >> JC42_CFG_HYST_SHIFT]; + *val = temp - hyst; + break; + case hwmon_temp_min_alarm: + ret = regmap_read(data->regmap, JC42_REG_TEMP, ®val); + if (ret) + break; + + *val = (regval >> JC42_ALARM_MIN_BIT) & 1; + break; + case hwmon_temp_max_alarm: + ret = regmap_read(data->regmap, JC42_REG_TEMP, ®val); + if (ret) + break; + + *val = (regval >> JC42_ALARM_MAX_BIT) & 1; + break; + case hwmon_temp_crit_alarm: + ret = regmap_read(data->regmap, JC42_REG_TEMP, ®val); + if (ret) + break; + + *val = (regval >> JC42_ALARM_CRIT_BIT) & 1; + break; + default: + ret = -EOPNOTSUPP; + break; + } + + mutex_unlock(&data->update_lock); + + return ret; +} + +static int jc42_write(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long val) +{ + struct jc42_data *data = dev_get_drvdata(dev); + unsigned int regval; + int diff, hyst; + int ret; + + mutex_lock(&data->update_lock); + + switch (attr) { + case hwmon_temp_min: + ret = regmap_write(data->regmap, JC42_REG_TEMP_LOWER, + jc42_temp_to_reg(val, data->extended)); + break; + case hwmon_temp_max: + ret = regmap_write(data->regmap, JC42_REG_TEMP_UPPER, + jc42_temp_to_reg(val, data->extended)); + break; + case hwmon_temp_crit: + ret = regmap_write(data->regmap, JC42_REG_TEMP_CRITICAL, + jc42_temp_to_reg(val, data->extended)); + break; + case hwmon_temp_crit_hyst: + ret = regmap_read(data->regmap, JC42_REG_TEMP_CRITICAL, + ®val); + if (ret) + break; + + /* + * JC42.4 compliant chips only support four hysteresis values. + * Pick best choice and go from there. + */ + val = clamp_val(val, (data->extended ? JC42_TEMP_MIN_EXTENDED + : JC42_TEMP_MIN) - 6000, + JC42_TEMP_MAX); + diff = jc42_temp_from_reg(regval) - val; + hyst = 0; + if (diff > 0) { + if (diff < 2250) + hyst = 1; /* 1.5 degrees C */ + else if (diff < 4500) + hyst = 2; /* 3.0 degrees C */ + else + hyst = 3; /* 6.0 degrees C */ + } + data->config = (data->config & ~JC42_CFG_HYST_MASK) | + (hyst << JC42_CFG_HYST_SHIFT); + ret = regmap_write(data->regmap, JC42_REG_CONFIG, + data->config); + break; + default: + ret = -EOPNOTSUPP; + break; + } + + mutex_unlock(&data->update_lock); + + return ret; +} + +static umode_t jc42_is_visible(const void *_data, enum hwmon_sensor_types type, + u32 attr, int channel) +{ + const struct jc42_data *data = _data; + unsigned int config = data->config; + umode_t mode = 0444; + + switch (attr) { + case hwmon_temp_min: + case hwmon_temp_max: + if (!(config & JC42_CFG_EVENT_LOCK)) + mode |= 0200; + break; + case hwmon_temp_crit: + if (!(config & JC42_CFG_TCRIT_LOCK)) + mode |= 0200; + break; + case hwmon_temp_crit_hyst: + if (!(config & (JC42_CFG_EVENT_LOCK | JC42_CFG_TCRIT_LOCK))) + mode |= 0200; + break; + case hwmon_temp_input: + case hwmon_temp_max_hyst: + case hwmon_temp_min_alarm: + case hwmon_temp_max_alarm: + case hwmon_temp_crit_alarm: + break; + default: + mode = 0; + break; + } + return mode; +} + +/* Return 0 if detection is successful, -ENODEV otherwise */ +static int jc42_detect(struct i2c_client *client, struct i2c_board_info *info) +{ + struct i2c_adapter *adapter = client->adapter; + int i, config, cap, manid, devid; + + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | + I2C_FUNC_SMBUS_WORD_DATA)) + return -ENODEV; + + cap = i2c_smbus_read_word_swapped(client, JC42_REG_CAP); + config = i2c_smbus_read_word_swapped(client, JC42_REG_CONFIG); + manid = i2c_smbus_read_word_swapped(client, JC42_REG_MANID); + devid = i2c_smbus_read_word_swapped(client, JC42_REG_DEVICEID); + + if (cap < 0 || config < 0 || manid < 0 || devid < 0) + return -ENODEV; + + if ((cap & 0xff00) || (config & 0xf800)) + return -ENODEV; + + for (i = 0; i < ARRAY_SIZE(jc42_chips); i++) { + struct jc42_chips *chip = &jc42_chips[i]; + if (manid == chip->manid && + (devid & chip->devid_mask) == chip->devid) { + strscpy(info->type, "jc42", I2C_NAME_SIZE); + return 0; + } + } + return -ENODEV; +} + +static const struct hwmon_channel_info *jc42_info[] = { + HWMON_CHANNEL_INFO(chip, + HWMON_C_REGISTER_TZ | HWMON_C_UPDATE_INTERVAL), + HWMON_CHANNEL_INFO(temp, + HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX | + HWMON_T_CRIT | HWMON_T_MAX_HYST | + HWMON_T_CRIT_HYST | HWMON_T_MIN_ALARM | + HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM), + NULL +}; + +static const struct hwmon_ops jc42_hwmon_ops = { + .is_visible = jc42_is_visible, + .read = jc42_read, + .write = jc42_write, +}; + +static const struct hwmon_chip_info jc42_chip_info = { + .ops = &jc42_hwmon_ops, + .info = jc42_info, +}; + +static bool jc42_readable_reg(struct device *dev, unsigned int reg) +{ + return (reg >= JC42_REG_CAP && reg <= JC42_REG_DEVICEID) || + reg == JC42_REG_SMBUS; +} + +static bool jc42_writable_reg(struct device *dev, unsigned int reg) +{ + return (reg >= JC42_REG_CONFIG && reg <= JC42_REG_TEMP_CRITICAL) || + reg == JC42_REG_SMBUS; +} + +static bool jc42_volatile_reg(struct device *dev, unsigned int reg) +{ + return reg == JC42_REG_CONFIG || reg == JC42_REG_TEMP; +} + +static const struct regmap_config jc42_regmap_config = { + .reg_bits = 8, + .val_bits = 16, + .val_format_endian = REGMAP_ENDIAN_BIG, + .max_register = JC42_REG_SMBUS, + .writeable_reg = jc42_writable_reg, + .readable_reg = jc42_readable_reg, + .volatile_reg = jc42_volatile_reg, + .cache_type = REGCACHE_RBTREE, +}; + +static int jc42_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct device *hwmon_dev; + unsigned int config, cap; + struct jc42_data *data; + int ret; + + data = devm_kzalloc(dev, sizeof(struct jc42_data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->regmap = devm_regmap_init_i2c(client, &jc42_regmap_config); + if (IS_ERR(data->regmap)) + return PTR_ERR(data->regmap); + + i2c_set_clientdata(client, data); + mutex_init(&data->update_lock); + + ret = regmap_read(data->regmap, JC42_REG_CAP, &cap); + if (ret) + return ret; + + data->extended = !!(cap & JC42_CAP_RANGE); + + if (device_property_read_bool(dev, "smbus-timeout-disable")) { + /* + * Not all chips support this register, but from a + * quick read of various datasheets no chip appears + * incompatible with the below attempt to disable + * the timeout. And the whole thing is opt-in... + */ + ret = regmap_set_bits(data->regmap, JC42_REG_SMBUS, + SMBUS_STMOUT); + if (ret) + return ret; + } + + ret = regmap_read(data->regmap, JC42_REG_CONFIG, &config); + if (ret) + return ret; + + data->orig_config = config; + if (config & JC42_CFG_SHUTDOWN) { + config &= ~JC42_CFG_SHUTDOWN; + regmap_write(data->regmap, JC42_REG_CONFIG, config); + } + data->config = config; + + hwmon_dev = devm_hwmon_device_register_with_info(dev, "jc42", + data, &jc42_chip_info, + NULL); + return PTR_ERR_OR_ZERO(hwmon_dev); +} + +static void jc42_remove(struct i2c_client *client) +{ + struct jc42_data *data = i2c_get_clientdata(client); + + /* Restore original configuration except hysteresis */ + if ((data->config & ~JC42_CFG_HYST_MASK) != + (data->orig_config & ~JC42_CFG_HYST_MASK)) { + int config; + + config = (data->orig_config & ~JC42_CFG_HYST_MASK) + | (data->config & JC42_CFG_HYST_MASK); + regmap_write(data->regmap, JC42_REG_CONFIG, config); + } +} + +#ifdef CONFIG_PM + +static int jc42_suspend(struct device *dev) +{ + struct jc42_data *data = dev_get_drvdata(dev); + + data->config |= JC42_CFG_SHUTDOWN; + regmap_write(data->regmap, JC42_REG_CONFIG, data->config); + + regcache_cache_only(data->regmap, true); + regcache_mark_dirty(data->regmap); + + return 0; +} + +static int jc42_resume(struct device *dev) +{ + struct jc42_data *data = dev_get_drvdata(dev); + + regcache_cache_only(data->regmap, false); + + data->config &= ~JC42_CFG_SHUTDOWN; + regmap_write(data->regmap, JC42_REG_CONFIG, data->config); + + /* Restore cached register values to hardware */ + return regcache_sync(data->regmap); +} + +static const struct dev_pm_ops jc42_dev_pm_ops = { + .suspend = jc42_suspend, + .resume = jc42_resume, +}; + +#define JC42_DEV_PM_OPS (&jc42_dev_pm_ops) +#else +#define JC42_DEV_PM_OPS NULL +#endif /* CONFIG_PM */ + +static const struct i2c_device_id jc42_id[] = { + { "jc42", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, jc42_id); + +#ifdef CONFIG_OF +static const struct of_device_id jc42_of_ids[] = { + { .compatible = "jedec,jc-42.4-temp", }, + { } +}; +MODULE_DEVICE_TABLE(of, jc42_of_ids); +#endif + +static struct i2c_driver jc42_driver = { + .class = I2C_CLASS_SPD | I2C_CLASS_HWMON, + .driver = { + .name = "jc42", + .pm = JC42_DEV_PM_OPS, + .of_match_table = of_match_ptr(jc42_of_ids), + }, + .probe_new = jc42_probe, + .remove = jc42_remove, + .id_table = jc42_id, + .detect = jc42_detect, + .address_list = normal_i2c, +}; + +module_i2c_driver(jc42_driver); + +MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>"); +MODULE_DESCRIPTION("JC42 driver"); +MODULE_LICENSE("GPL"); |