diff options
Diffstat (limited to 'drivers/hwmon/drivetemp.c')
| -rw-r--r-- | drivers/hwmon/drivetemp.c | 574 |
1 files changed, 574 insertions, 0 deletions
diff --git a/drivers/hwmon/drivetemp.c b/drivers/hwmon/drivetemp.c new file mode 100644 index 000000000000..370d0c74eb01 --- /dev/null +++ b/drivers/hwmon/drivetemp.c @@ -0,0 +1,574 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Hwmon client for disk and solid state drives with temperature sensors + * Copyright (C) 2019 Zodiac Inflight Innovations + * + * With input from: + * Hwmon client for S.M.A.R.T. hard disk drives with temperature sensors. + * (C) 2018 Linus Walleij + * + * hwmon: Driver for SCSI/ATA temperature sensors + * by Constantin Baranov <const@mimas.ru>, submitted September 2009 + * + * This drive supports reporting the temperatire of SATA drives. It can be + * easily extended to report the temperature of SCSI drives. + * + * The primary means to read drive temperatures and temperature limits + * for ATA drives is the SCT Command Transport feature set as specified in + * ATA8-ACS. + * It can be used to read the current drive temperature, temperature limits, + * and historic minimum and maximum temperatures. The SCT Command Transport + * feature set is documented in "AT Attachment 8 - ATA/ATAPI Command Set + * (ATA8-ACS)". + * + * If the SCT Command Transport feature set is not available, drive temperatures + * may be readable through SMART attributes. Since SMART attributes are not well + * defined, this method is only used as fallback mechanism. + * + * There are three SMART attributes which may report drive temperatures. + * Those are defined as follows (from + * http://www.cropel.com/library/smart-attribute-list.aspx). + * + * 190 Temperature Temperature, monitored by a sensor somewhere inside + * the drive. Raw value typicaly holds the actual + * temperature (hexadecimal) in its rightmost two digits. + * + * 194 Temperature Temperature, monitored by a sensor somewhere inside + * the drive. Raw value typicaly holds the actual + * temperature (hexadecimal) in its rightmost two digits. + * + * 231 Temperature Temperature, monitored by a sensor somewhere inside + * the drive. Raw value typicaly holds the actual + * temperature (hexadecimal) in its rightmost two digits. + * + * Wikipedia defines attributes a bit differently. + * + * 190 Temperature Value is equal to (100-temp. °C), allowing manufacturer + * Difference or to set a minimum threshold which corresponds to a + * Airflow maximum temperature. This also follows the convention of + * Temperature 100 being a best-case value and lower values being + * undesirable. However, some older drives may instead + * report raw Temperature (identical to 0xC2) or + * Temperature minus 50 here. + * 194 Temperature or Indicates the device temperature, if the appropriate + * Temperature sensor is fitted. Lowest byte of the raw value contains + * Celsius the exact temperature value (Celsius degrees). + * 231 Life Left Indicates the approximate SSD life left, in terms of + * (SSDs) or program/erase cycles or available reserved blocks. + * Temperature A normalized value of 100 represents a new drive, with + * a threshold value at 10 indicating a need for + * replacement. A value of 0 may mean that the drive is + * operating in read-only mode to allow data recovery. + * Previously (pre-2010) occasionally used for Drive + * Temperature (more typically reported at 0xC2). + * + * Common denominator is that the first raw byte reports the temperature + * in degrees C on almost all drives. Some drives may report a fractional + * temperature in the second raw byte. + * + * Known exceptions (from libatasmart): + * - SAMSUNG SV0412H and SAMSUNG SV1204H) report the temperature in 10th + * degrees C in the first two raw bytes. + * - A few Maxtor drives report an unknown or bad value in attribute 194. + * - Certain Apple SSD drives report an unknown value in attribute 190. + * Only certain firmware versions are affected. + * + * Those exceptions affect older ATA drives and are currently ignored. + * Also, the second raw byte (possibly reporting the fractional temperature) + * is currently ignored. + * + * Many drives also report temperature limits in additional SMART data raw + * bytes. The format of those is not well defined and varies widely. + * The driver does not currently attempt to report those limits. + * + * According to data in smartmontools, attribute 231 is rarely used to report + * drive temperatures. At the same time, several drives report SSD life left + * in attribute 231, but do not support temperature sensors. For this reason, + * attribute 231 is currently ignored. + * + * Following above definitions, temperatures are reported as follows. + * If SCT Command Transport is supported, it is used to read the + * temperature and, if available, temperature limits. + * - Otherwise, if SMART attribute 194 is supported, it is used to read + * the temperature. + * - Otherwise, if SMART attribute 190 is supported, it is used to read + * the temperature. + */ + +#include <linux/ata.h> +#include <linux/bits.h> +#include <linux/device.h> +#include <linux/hwmon.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <scsi/scsi_cmnd.h> +#include <scsi/scsi_device.h> +#include <scsi/scsi_driver.h> +#include <scsi/scsi_proto.h> + +struct drivetemp_data { + struct list_head list; /* list of instantiated devices */ + struct mutex lock; /* protect data buffer accesses */ + struct scsi_device *sdev; /* SCSI device */ + struct device *dev; /* instantiating device */ + struct device *hwdev; /* hardware monitoring device */ + u8 smartdata[ATA_SECT_SIZE]; /* local buffer */ + int (*get_temp)(struct drivetemp_data *st, u32 attr, long *val); + bool have_temp_lowest; /* lowest temp in SCT status */ + bool have_temp_highest; /* highest temp in SCT status */ + bool have_temp_min; /* have min temp */ + bool have_temp_max; /* have max temp */ + bool have_temp_lcrit; /* have lower critical limit */ + bool have_temp_crit; /* have critical limit */ + int temp_min; /* min temp */ + int temp_max; /* max temp */ + int temp_lcrit; /* lower critical limit */ + int temp_crit; /* critical limit */ +}; + +static LIST_HEAD(drivetemp_devlist); + +#define ATA_MAX_SMART_ATTRS 30 +#define SMART_TEMP_PROP_190 190 +#define SMART_TEMP_PROP_194 194 + +#define SCT_STATUS_REQ_ADDR 0xe0 +#define SCT_STATUS_VERSION_LOW 0 /* log byte offsets */ +#define SCT_STATUS_VERSION_HIGH 1 +#define SCT_STATUS_TEMP 200 +#define SCT_STATUS_TEMP_LOWEST 201 +#define SCT_STATUS_TEMP_HIGHEST 202 +#define SCT_READ_LOG_ADDR 0xe1 +#define SMART_READ_LOG 0xd5 +#define SMART_WRITE_LOG 0xd6 + +#define INVALID_TEMP 0x80 + +#define temp_is_valid(temp) ((temp) != INVALID_TEMP) +#define temp_from_sct(temp) (((s8)(temp)) * 1000) + +static inline bool ata_id_smart_supported(u16 *id) +{ + return id[ATA_ID_COMMAND_SET_1] & BIT(0); +} + +static inline bool ata_id_smart_enabled(u16 *id) +{ + return id[ATA_ID_CFS_ENABLE_1] & BIT(0); +} + +static int drivetemp_scsi_command(struct drivetemp_data *st, + u8 ata_command, u8 feature, + u8 lba_low, u8 lba_mid, u8 lba_high) +{ + u8 scsi_cmd[MAX_COMMAND_SIZE]; + int data_dir; + + memset(scsi_cmd, 0, sizeof(scsi_cmd)); + scsi_cmd[0] = ATA_16; + if (ata_command == ATA_CMD_SMART && feature == SMART_WRITE_LOG) { + scsi_cmd[1] = (5 << 1); /* PIO Data-out */ + /* + * No off.line or cc, write to dev, block count in sector count + * field. + */ + scsi_cmd[2] = 0x06; + data_dir = DMA_TO_DEVICE; + } else { + scsi_cmd[1] = (4 << 1); /* PIO Data-in */ + /* + * No off.line or cc, read from dev, block count in sector count + * field. + */ + scsi_cmd[2] = 0x0e; + data_dir = DMA_FROM_DEVICE; + } + scsi_cmd[4] = feature; + scsi_cmd[6] = 1; /* 1 sector */ + scsi_cmd[8] = lba_low; + scsi_cmd[10] = lba_mid; + scsi_cmd[12] = lba_high; + scsi_cmd[14] = ata_command; + + return scsi_execute_req(st->sdev, scsi_cmd, data_dir, + st->smartdata, ATA_SECT_SIZE, NULL, HZ, 5, + NULL); +} + +static int drivetemp_ata_command(struct drivetemp_data *st, u8 feature, + u8 select) +{ + return drivetemp_scsi_command(st, ATA_CMD_SMART, feature, select, + ATA_SMART_LBAM_PASS, ATA_SMART_LBAH_PASS); +} + +static int drivetemp_get_smarttemp(struct drivetemp_data *st, u32 attr, + long *temp) +{ + u8 *buf = st->smartdata; + bool have_temp = false; + u8 temp_raw; + u8 csum; + int err; + int i; + + err = drivetemp_ata_command(st, ATA_SMART_READ_VALUES, 0); + if (err) + return err; + + /* Checksum the read value table */ + csum = 0; + for (i = 0; i < ATA_SECT_SIZE; i++) + csum += buf[i]; + if (csum) { + dev_dbg(&st->sdev->sdev_gendev, + "checksum error reading SMART values\n"); + return -EIO; + } + + for (i = 0; i < ATA_MAX_SMART_ATTRS; i++) { + u8 *attr = buf + i * 12; + int id = attr[2]; + + if (!id) + continue; + + if (id == SMART_TEMP_PROP_190) { + temp_raw = attr[7]; + have_temp = true; + } + if (id == SMART_TEMP_PROP_194) { + temp_raw = attr[7]; + have_temp = true; + break; + } + } + + if (have_temp) { + *temp = temp_raw * 1000; + return 0; + } + + return -ENXIO; +} + +static int drivetemp_get_scttemp(struct drivetemp_data *st, u32 attr, long *val) +{ + u8 *buf = st->smartdata; + int err; + + err = drivetemp_ata_command(st, SMART_READ_LOG, SCT_STATUS_REQ_ADDR); + if (err) + return err; + switch (attr) { + case hwmon_temp_input: + *val = temp_from_sct(buf[SCT_STATUS_TEMP]); + break; + case hwmon_temp_lowest: + *val = temp_from_sct(buf[SCT_STATUS_TEMP_LOWEST]); + break; + case hwmon_temp_highest: + *val = temp_from_sct(buf[SCT_STATUS_TEMP_HIGHEST]); + break; + default: + err = -EINVAL; + break; + } + return err; +} + +static int drivetemp_identify_sata(struct drivetemp_data *st) +{ + struct scsi_device *sdev = st->sdev; + u8 *buf = st->smartdata; + struct scsi_vpd *vpd; + bool is_ata, is_sata; + bool have_sct_data_table; + bool have_sct_temp; + bool have_smart; + bool have_sct; + u16 *ata_id; + u16 version; + long temp; + int err; + + /* SCSI-ATA Translation present? */ + rcu_read_lock(); + vpd = rcu_dereference(sdev->vpd_pg89); + + /* + * Verify that ATA IDENTIFY DEVICE data is included in ATA Information + * VPD and that the drive implements the SATA protocol. + */ + if (!vpd || vpd->len < 572 || vpd->data[56] != ATA_CMD_ID_ATA || + vpd->data[36] != 0x34) { + rcu_read_unlock(); + return -ENODEV; + } + ata_id = (u16 *)&vpd->data[60]; + is_ata = ata_id_is_ata(ata_id); + is_sata = ata_id_is_sata(ata_id); + have_sct = ata_id_sct_supported(ata_id); + have_sct_data_table = ata_id_sct_data_tables(ata_id); + have_smart = ata_id_smart_supported(ata_id) && + ata_id_smart_enabled(ata_id); + + rcu_read_unlock(); + + /* bail out if this is not a SATA device */ + if (!is_ata || !is_sata) + return -ENODEV; + if (!have_sct) + goto skip_sct; + + err = drivetemp_ata_command(st, SMART_READ_LOG, SCT_STATUS_REQ_ADDR); + if (err) + goto skip_sct; + + version = (buf[SCT_STATUS_VERSION_HIGH] << 8) | + buf[SCT_STATUS_VERSION_LOW]; + if (version != 2 && version != 3) + goto skip_sct; + + have_sct_temp = temp_is_valid(buf[SCT_STATUS_TEMP]); + if (!have_sct_temp) + goto skip_sct; + + st->have_temp_lowest = temp_is_valid(buf[SCT_STATUS_TEMP_LOWEST]); + st->have_temp_highest = temp_is_valid(buf[SCT_STATUS_TEMP_HIGHEST]); + + if (!have_sct_data_table) + goto skip_sct; + + /* Request and read temperature history table */ + memset(buf, '\0', sizeof(st->smartdata)); + buf[0] = 5; /* data table command */ + buf[2] = 1; /* read table */ + buf[4] = 2; /* temperature history table */ + + err = drivetemp_ata_command(st, SMART_WRITE_LOG, SCT_STATUS_REQ_ADDR); + if (err) + goto skip_sct_data; + + err = drivetemp_ata_command(st, SMART_READ_LOG, SCT_READ_LOG_ADDR); + if (err) + goto skip_sct_data; + + /* + * Temperature limits per AT Attachment 8 - + * ATA/ATAPI Command Set (ATA8-ACS) + */ + st->have_temp_max = temp_is_valid(buf[6]); + st->have_temp_crit = temp_is_valid(buf[7]); + st->have_temp_min = temp_is_valid(buf[8]); + st->have_temp_lcrit = temp_is_valid(buf[9]); + + st->temp_max = temp_from_sct(buf[6]); + st->temp_crit = temp_from_sct(buf[7]); + st->temp_min = temp_from_sct(buf[8]); + st->temp_lcrit = temp_from_sct(buf[9]); + +skip_sct_data: + if (have_sct_temp) { + st->get_temp = drivetemp_get_scttemp; + return 0; + } +skip_sct: + if (!have_smart) + return -ENODEV; + st->get_temp = drivetemp_get_smarttemp; + return drivetemp_get_smarttemp(st, hwmon_temp_input, &temp); +} + +static int drivetemp_identify(struct drivetemp_data *st) +{ + struct scsi_device *sdev = st->sdev; + + /* Bail out immediately if there is no inquiry data */ + if (!sdev->inquiry || sdev->inquiry_len < 16) + return -ENODEV; + + /* Disk device? */ + if (sdev->type != TYPE_DISK && sdev->type != TYPE_ZBC) + return -ENODEV; + + return drivetemp_identify_sata(st); +} + +static int drivetemp_read(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long *val) +{ + struct drivetemp_data *st = dev_get_drvdata(dev); + int err = 0; + + if (type != hwmon_temp) + return -EINVAL; + + switch (attr) { + case hwmon_temp_input: + case hwmon_temp_lowest: + case hwmon_temp_highest: + mutex_lock(&st->lock); + err = st->get_temp(st, attr, val); + mutex_unlock(&st->lock); + break; + case hwmon_temp_lcrit: + *val = st->temp_lcrit; + break; + case hwmon_temp_min: + *val = st->temp_min; + break; + case hwmon_temp_max: + *val = st->temp_max; + break; + case hwmon_temp_crit: + *val = st->temp_crit; + break; + default: + err = -EINVAL; + break; + } + return err; +} + +static umode_t drivetemp_is_visible(const void *data, + enum hwmon_sensor_types type, + u32 attr, int channel) +{ + const struct drivetemp_data *st = data; + + switch (type) { + case hwmon_temp: + switch (attr) { + case hwmon_temp_input: + return 0444; + case hwmon_temp_lowest: + if (st->have_temp_lowest) + return 0444; + break; + case hwmon_temp_highest: + if (st->have_temp_highest) + return 0444; + break; + case hwmon_temp_min: + if (st->have_temp_min) + return 0444; + break; + case hwmon_temp_max: + if (st->have_temp_max) + return 0444; + break; + case hwmon_temp_lcrit: + if (st->have_temp_lcrit) + return 0444; + break; + case hwmon_temp_crit: + if (st->have_temp_crit) + return 0444; + break; + default: + break; + } + break; + default: + break; + } + return 0; +} + +static const struct hwmon_channel_info *drivetemp_info[] = { + HWMON_CHANNEL_INFO(chip, + HWMON_C_REGISTER_TZ), + HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT | + HWMON_T_LOWEST | HWMON_T_HIGHEST | + HWMON_T_MIN | HWMON_T_MAX | + HWMON_T_LCRIT | HWMON_T_CRIT), + NULL +}; + +static const struct hwmon_ops drivetemp_ops = { + .is_visible = drivetemp_is_visible, + .read = drivetemp_read, +}; + +static const struct hwmon_chip_info drivetemp_chip_info = { + .ops = &drivetemp_ops, + .info = drivetemp_info, +}; + +/* + * The device argument points to sdev->sdev_dev. Its parent is + * sdev->sdev_gendev, which we can use to get the scsi_device pointer. + */ +static int drivetemp_add(struct device *dev, struct class_interface *intf) +{ + struct scsi_device *sdev = to_scsi_device(dev->parent); + struct drivetemp_data *st; + int err; + + st = kzalloc(sizeof(*st), GFP_KERNEL); + if (!st) + return -ENOMEM; + + st->sdev = sdev; + st->dev = dev; + mutex_init(&st->lock); + + if (drivetemp_identify(st)) { + err = -ENODEV; + goto abort; + } + + st->hwdev = hwmon_device_register_with_info(dev->parent, "drivetemp", + st, &drivetemp_chip_info, + NULL); + if (IS_ERR(st->hwdev)) { + err = PTR_ERR(st->hwdev); + goto abort; + } + + list_add(&st->list, &drivetemp_devlist); + return 0; + +abort: + kfree(st); + return err; +} + +static void drivetemp_remove(struct device *dev, struct class_interface *intf) +{ + struct drivetemp_data *st, *tmp; + + list_for_each_entry_safe(st, tmp, &drivetemp_devlist, list) { + if (st->dev == dev) { + list_del(&st->list); + hwmon_device_unregister(st->hwdev); + kfree(st); + break; + } + } +} + +static struct class_interface drivetemp_interface = { + .add_dev = drivetemp_add, + .remove_dev = drivetemp_remove, +}; + +static int __init drivetemp_init(void) +{ + return scsi_register_interface(&drivetemp_interface); +} + +static void __exit drivetemp_exit(void) +{ + scsi_unregister_interface(&drivetemp_interface); +} + +module_init(drivetemp_init); +module_exit(drivetemp_exit); + +MODULE_AUTHOR("Guenter Roeck <linus@roeck-us.net>"); +MODULE_DESCRIPTION("Hard drive temperature monitor"); +MODULE_LICENSE("GPL"); |