// SPDX-License-Identifier: GPL-2.0-or-later /* * w1_therm.c * * Copyright (c) 2004 Evgeniy Polyakov */ #include #include #include #include #include #include #include #include #include #include #include #include #define W1_THERM_DS18S20 0x10 #define W1_THERM_DS1822 0x22 #define W1_THERM_DS18B20 0x28 #define W1_THERM_DS1825 0x3B #define W1_THERM_DS28EA00 0x42 /* * Allow the strong pullup to be disabled, but default to enabled. * If it was disabled a parasite powered device might not get the require * current to do a temperature conversion. If it is enabled parasite powered * devices have a better chance of getting the current required. * In case the parasite power-detection is not working (seems to be the case * for some DS18S20) the strong pullup can also be forced, regardless of the * power state of the devices. * * Summary of options: * - strong_pullup = 0 Disable strong pullup completely * - strong_pullup = 1 Enable automatic strong pullup detection * - strong_pullup = 2 Force strong pullup */ static int w1_strong_pullup = 1; module_param_named(strong_pullup, w1_strong_pullup, int, 0); /* Nb of try for an operation */ #define W1_THERM_MAX_TRY 5 /* ms delay to retry bus mutex */ #define W1_THERM_RETRY_DELAY 20 /* Helpers Macros */ /* * return a pointer on the slave w1_therm_family_converter struct: * always test family data existence before using this macro */ #define SLAVE_SPECIFIC_FUNC(sl) \ (((struct w1_therm_family_data *)(sl->family_data))->specific_functions) /* * return the power mode of the sl slave : 1-ext, 0-parasite, <0 unknown * always test family data existence before using this macro */ #define SLAVE_POWERMODE(sl) \ (((struct w1_therm_family_data *)(sl->family_data))->external_powered) /* * return the resolution in bit of the sl slave : <0 unknown * always test family data existence before using this macro */ #define SLAVE_RESOLUTION(sl) \ (((struct w1_therm_family_data *)(sl->family_data))->resolution) /* return the address of the refcnt in the family data */ #define THERM_REFCNT(family_data) \ (&((struct w1_therm_family_data *)family_data)->refcnt) /* Structs definition */ /** * struct w1_therm_family_converter - bind device specific functions * @broken: flag for non-registred families * @reserved: not used here * @f: pointer to the device binding structure * @convert: pointer to the device conversion function * @set_resolution: pointer to the device set_resolution function * @get_resolution: pointer to the device get_resolution function * @eeprom: pointer to eeprom function */ struct w1_therm_family_converter { u8 broken; u16 reserved; struct w1_family *f; int (*convert)(u8 rom[9]); int (*set_resolution)(struct w1_slave *sl, int val); int (*get_resolution)(struct w1_slave *sl); int (*eeprom)(struct device *device); }; /** * struct w1_therm_family_data - device data * @rom: ROM device id (64bit Lasered ROM code + 1 CRC byte) * @refcnt: ref count * @external_powered: 1 device powered externally, * 0 device parasite powered, * -x error or undefined * @resolution: current device resolution * @specific_functions: pointer to struct of device specific function */ struct w1_therm_family_data { uint8_t rom[9]; atomic_t refcnt; int external_powered; int resolution; struct w1_therm_family_converter *specific_functions; }; /** * struct therm_info - store temperature reading * @rom: read device data (8 data bytes + 1 CRC byte) * @crc: computed crc from rom * @verdict: 1 crc checked, 0 crc not matching */ struct therm_info { u8 rom[9]; u8 crc; u8 verdict; }; /* Hardware Functions declaration */ /** * reset_select_slave() - reset and select a slave * @sl: the slave to select * * Resets the bus and select the slave by sending a ROM MATCH cmd * w1_reset_select_slave() from w1_io.c could not be used here because * it sent a SKIP ROM command if only one device is on the line. * At the beginning of the such process, sl->master->slave_count is 1 even if * more devices are on the line, causing collision on the line. * * Context: The w1 master lock must be held. * * Return: 0 if success, negative kernel error code otherwise. */ static int reset_select_slave(struct w1_slave *sl); /** * read_scratchpad() - read the data in device RAM * @sl: pointer to the slave to read * @info: pointer to a structure to store the read results * * Return: 0 if success, -kernel error code otherwise */ static int read_scratchpad(struct w1_slave *sl, struct therm_info *info); /** * write_scratchpad() - write nb_bytes in the device RAM * @sl: pointer to the slave to write in * @data: pointer to an array of 3 bytes, as 3 bytes MUST be written * @nb_bytes: number of bytes to be written (2 for DS18S20, 3 otherwise) * * Return: 0 if success, -kernel error code otherwise */ static int write_scratchpad(struct w1_slave *sl, const u8 *data, u8 nb_bytes); /** * read_powermode() - Query the power mode of the slave * @sl: slave to retrieve the power mode * * Ask the device to get its power mode (external or parasite) * and store the power status in the &struct w1_therm_family_data. * * Return: * * 0 parasite powered device * * 1 externally powered device * * <0 kernel error code */ static int read_powermode(struct w1_slave *sl); /* Sysfs interface declaration */ static ssize_t w1_slave_show(struct device *device, struct device_attribute *attr, char *buf); static ssize_t w1_slave_store(struct device *device, struct device_attribute *attr, const char *buf, size_t size); static ssize_t w1_seq_show(struct device *device, struct device_attribute *attr, char *buf); static ssize_t ext_power_show(struct device *device, struct device_attribute *attr, char *buf); static ssize_t resolution_show(struct device *device, struct device_attribute *attr, char *buf); static ssize_t resolution_store(struct device *device, struct device_attribute *attr, const char *buf, size_t size); /* Attributes declarations */ static DEVICE_ATTR_RW(w1_slave); static DEVICE_ATTR_RO(w1_seq); static DEVICE_ATTR_RO(ext_power); static DEVICE_ATTR_RW(resolution); /* Interface Functions declaration */ /** * w1_therm_add_slave() - Called when a new slave is discovered * @sl: slave just discovered by the master. * * Called by the master when the slave is discovered on the bus. Used to * initialize slave state before the beginning of any communication. * * Return: 0 - If success, negative kernel code otherwise */ static int w1_therm_add_slave(struct w1_slave *sl); /** * w1_therm_remove_slave() - Called when a slave is removed * @sl: slave to be removed. * * Called by the master when the slave is considered not to be on the bus * anymore. Used to free memory. */ static void w1_therm_remove_slave(struct w1_slave *sl); /* Family attributes */ static struct attribute *w1_therm_attrs[] = { &dev_attr_w1_slave.attr, &dev_attr_ext_power.attr, &dev_attr_resolution.attr, NULL, }; static struct attribute *w1_ds18s20_attrs[] = { &dev_attr_w1_slave.attr, &dev_attr_ext_power.attr, NULL, }; static struct attribute *w1_ds28ea00_attrs[] = { &dev_attr_w1_slave.attr, &dev_attr_w1_seq.attr, &dev_attr_ext_power.attr, &dev_attr_resolution.attr, NULL, }; /* Attribute groups */ ATTRIBUTE_GROUPS(w1_therm); ATTRIBUTE_GROUPS(w1_ds18s20); ATTRIBUTE_GROUPS(w1_ds28ea00); #if IS_REACHABLE(CONFIG_HWMON) static int w1_read_temp(struct device *dev, u32 attr, int channel, long *val); static umode_t w1_is_visible(const void *_data, enum hwmon_sensor_types type, u32 attr, int channel) { return attr == hwmon_temp_input ? 0444 : 0; } static int w1_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel, long *val) { switch (type) { case hwmon_temp: return w1_read_temp(dev, attr, channel, val); default: return -EOPNOTSUPP; } } static const u32 w1_temp_config[] = { HWMON_T_INPUT, 0 }; static const struct hwmon_channel_info w1_temp = { .type = hwmon_temp, .config = w1_temp_config, }; static const struct hwmon_channel_info *w1_info[] = { &w1_temp, NULL }; static const struct hwmon_ops w1_hwmon_ops = { .is_visible = w1_is_visible, .read = w1_read, }; static const struct hwmon_chip_info w1_chip_info = { .ops = &w1_hwmon_ops, .info = w1_info, }; #define W1_CHIPINFO (&w1_chip_info) #else #define W1_CHIPINFO NULL #endif /* Family operations */ static struct w1_family_ops w1_therm_fops = { .add_slave = w1_therm_add_slave, .remove_slave = w1_therm_remove_slave, .groups = w1_therm_groups, .chip_info = W1_CHIPINFO, }; static struct w1_family_ops w1_ds18s20_fops = { .add_slave = w1_therm_add_slave, .remove_slave = w1_therm_remove_slave, .groups = w1_ds18s20_groups, .chip_info = W1_CHIPINFO, }; static struct w1_family_ops w1_ds28ea00_fops = { .add_slave = w1_therm_add_slave, .remove_slave = w1_therm_remove_slave, .groups = w1_ds28ea00_groups, .chip_info = W1_CHIPINFO, }; /* Family binding operations struct */ static struct w1_family w1_therm_family_DS18S20 = { .fid = W1_THERM_DS18S20, .fops = &w1_ds18s20_fops, }; static struct w1_family w1_therm_family_DS18B20 = { .fid = W1_THERM_DS18B20, .fops = &w1_therm_fops, }; static struct w1_family w1_therm_family_DS1822 = { .fid = W1_THERM_DS1822, .fops = &w1_therm_fops, }; static struct w1_family w1_therm_family_DS28EA00 = { .fid = W1_THERM_DS28EA00, .fops = &w1_ds28ea00_fops, }; static struct w1_family w1_therm_family_DS1825 = { .fid = W1_THERM_DS1825, .fops = &w1_therm_fops, }; /* Device dependent func */ /* write configuration to eeprom */ static inline int w1_therm_eeprom(struct device *device); static inline int w1_DS18B20_write_data(struct w1_slave *sl, const u8 *data) { return write_scratchpad(sl, data, 3); } static inline int w1_DS18S20_write_data(struct w1_slave *sl, const u8 *data) { /* No config register */ return write_scratchpad(sl, data, 2); } static inline int w1_DS18B20_set_resolution(struct w1_slave *sl, int val) { int ret = -ENODEV; u8 new_config_register[3]; /* array of data to be written */ struct therm_info info; /* resolution of DS18B20 is in the range [9..12] bits */ if (val < 9 || val > 12) return -EINVAL; val -= 9; /* soustract 9 the lowest resolution in bit */ val = (val << 5); /* shift to position bit 5 & bit 6 */ /* * Read the scratchpad to change only the required bits * (bit5 & bit 6 from byte 4) */ ret = read_scratchpad(sl, &info); if (!ret) { new_config_register[0] = info.rom[2]; new_config_register[1] = info.rom[3]; /* config register is byte 4 & mask 0b10011111*/ new_config_register[2] = (info.rom[4] & 0x9F) | (u8) val; } else return ret; /* Write data in the device RAM */ ret = w1_DS18B20_write_data(sl, new_config_register); return ret; } static inline int w1_DS18B20_get_resolution(struct w1_slave *sl) { int ret = -ENODEV; u8 config_register; struct therm_info info; ret = read_scratchpad(sl, &info); if (!ret) { config_register = info.rom[4]; /* config register is byte 4 */ config_register &= 0x60; /* 0b01100000 keep only bit 5 & 6 */ config_register = (config_register >> 5); /* shift */ config_register += 9; /* add 9 the lowest resolution in bit */ ret = (int) config_register; } return ret; } /** * w1_DS18B20_convert_temp() - temperature computation for DS18B20 * @rom: data read from device RAM (8 data bytes + 1 CRC byte) * * Can be called for any DS18B20 compliant device. * * Return: value in millidegrees Celsius. */ static inline int w1_DS18B20_convert_temp(u8 rom[9]) { s16 t = le16_to_cpup((__le16 *)rom); return t*1000/16; } /** * w1_DS18S20_convert_temp() - temperature computation for DS18S20 * @rom: data read from device RAM (8 data bytes + 1 CRC byte) * * Can be called for any DS18S20 compliant device. * * Return: value in millidegrees Celsius. */ static inline int w1_DS18S20_convert_temp(u8 rom[9]) { int t, h; if (!rom[7]) return 0; if (rom[1] == 0) t = ((s32)rom[0] >> 1)*1000; else t = 1000*(-1*(s32)(0x100-rom[0]) >> 1); t -= 250; h = 1000*((s32)rom[7] - (s32)rom[6]); h /= (s32)rom[7]; t += h; return t; } /* Device capability description */ static struct w1_therm_family_converter w1_therm_families[] = { { .f = &w1_therm_family_DS18S20, .convert = w1_DS18S20_convert_temp, .set_resolution = NULL, /* no config register */ .get_resolution = NULL, /* no config register */ .eeprom = w1_therm_eeprom }, { .f = &w1_therm_family_DS1822, .convert = w1_DS18B20_convert_temp, .set_resolution = w1_DS18B20_set_resolution, .get_resolution = w1_DS18B20_get_resolution, .eeprom = w1_therm_eeprom }, { .f = &w1_therm_family_DS18B20, .convert = w1_DS18B20_convert_temp, .set_resolution = w1_DS18B20_set_resolution, .get_resolution = w1_DS18B20_get_resolution, .eeprom = w1_therm_eeprom }, { .f = &w1_therm_family_DS28EA00, .convert = w1_DS18B20_convert_temp, .set_resolution = w1_DS18B20_set_resolution, .get_resolution = w1_DS18B20_get_resolution, .eeprom = w1_therm_eeprom }, { .f = &w1_therm_family_DS1825, .convert = w1_DS18B20_convert_temp, .set_resolution = w1_DS18B20_set_resolution, .get_resolution = w1_DS18B20_get_resolution, .eeprom = w1_therm_eeprom } }; /* Helpers Functions */ /** * device_family() - Retrieve a pointer on &struct w1_therm_family_converter * @sl: slave to retrieve the device specific structure * * Return: pointer to the slaves's family converter, NULL if not known */ static struct w1_therm_family_converter *device_family(struct w1_slave *sl) { struct w1_therm_family_converter *ret = NULL; int i; for (i = 0; i < ARRAY_SIZE(w1_therm_families); ++i) { if (w1_therm_families[i].f->fid == sl->family->fid) { ret = &w1_therm_families[i]; break; } } return ret; } /** * bus_mutex_lock() - Acquire the mutex * @lock: w1 bus mutex to acquire * * It try to acquire the mutex W1_THERM_MAX_TRY times and wait * W1_THERM_RETRY_DELAY between 2 attempts. * * Return: true is mutex is acquired and lock, false otherwise */ static inline bool bus_mutex_lock(struct mutex *lock) { int max_trying = W1_THERM_MAX_TRY; /* try to acquire the mutex, if not, sleep retry_delay before retry) */ while (mutex_lock_interruptible(lock) != 0 && max_trying > 0) { unsigned long sleep_rem; sleep_rem = msleep_interruptible(W1_THERM_RETRY_DELAY); if (!sleep_rem) max_trying--; } if (!max_trying) return false; /* Didn't acquire the bus mutex */ return true; } /** * w1_convert_temp() - temperature conversion binding function * @rom: data read from device RAM (8 data bytes + 1 CRC byte) * @fid: device family id * * The function call the temperature computation function according to * device family. * * Return: value in millidegrees Celsius. */ static inline int w1_convert_temp(u8 rom[9], u8 fid) { int i; for (i = 0; i < ARRAY_SIZE(w1_therm_families); ++i) if (w1_therm_families[i].f->fid == fid) return w1_therm_families[i].convert(rom); return 0; } /* Interface Functions */ static int w1_therm_add_slave(struct w1_slave *sl) { struct w1_therm_family_converter *sl_family_conv; /* Allocate memory */ sl->family_data = kzalloc(sizeof(struct w1_therm_family_data), GFP_KERNEL); if (!sl->family_data) return -ENOMEM; atomic_set(THERM_REFCNT(sl->family_data), 1); /* Get a pointer to the device specific function struct */ sl_family_conv = device_family(sl); if (!sl_family_conv) { kfree(sl->family_data); return -ENODEV; } /* save this pointer to the device structure */ SLAVE_SPECIFIC_FUNC(sl) = sl_family_conv; /* Getting the power mode of the device {external, parasite} */ SLAVE_POWERMODE(sl) = read_powermode(sl); if (SLAVE_POWERMODE(sl) < 0) { /* no error returned as device has been added */ dev_warn(&sl->dev, "%s: Device has been added, but power_mode may be corrupted. err=%d\n", __func__, SLAVE_POWERMODE(sl)); } /* Getting the resolution of the device */ if (SLAVE_SPECIFIC_FUNC(sl)->get_resolution) { SLAVE_RESOLUTION(sl) = SLAVE_SPECIFIC_FUNC(sl)->get_resolution(sl); if (SLAVE_RESOLUTION(sl) < 0) { /* no error returned as device has been added */ dev_warn(&sl->dev, "%s:Device has been added, but resolution may be corrupted. err=%d\n", __func__, SLAVE_RESOLUTION(sl)); } } return 0; } static void w1_therm_remove_slave(struct w1_slave *sl) { int refcnt = atomic_sub_return(1, THERM_REFCNT(sl->family_data)); while (refcnt) { msleep(1000); refcnt = atomic_read(THERM_REFCNT(sl->family_data)); } kfree(sl->family_data); sl->family_data = NULL; } /* Hardware Functions */ /* Safe version of reset_select_slave - avoid using the one in w_io.c */ static int reset_select_slave(struct w1_slave *sl) { u8 match[9] = { W1_MATCH_ROM, }; u64 rn = le64_to_cpu(*((u64 *)&sl->reg_num)); if (w1_reset_bus(sl->master)) return -ENODEV; memcpy(&match[1], &rn, 8); w1_write_block(sl->master, match, 9); return 0; } static ssize_t read_therm(struct device *device, struct w1_slave *sl, struct therm_info *info) { struct w1_master *dev = sl->master; u8 external_power; int ret, max_trying = 10; u8 *family_data = sl->family_data; if (!family_data) { ret = -ENODEV; goto error; } /* prevent the slave from going away in sleep */ atomic_inc(THERM_REFCNT(family_data)); ret = mutex_lock_interruptible(&dev->bus_mutex); if (ret != 0) goto dec_refcnt; memset(info->rom, 0, sizeof(info->rom)); while (max_trying--) { info->verdict = 0; info->crc = 0; if (!reset_select_slave(sl)) { int count = 0; unsigned int tm = 750; unsigned long sleep_rem; w1_write_8(dev, W1_READ_PSUPPLY); external_power = w1_read_8(dev); if (reset_select_slave(sl)) continue; /* 750ms strong pullup (or delay) after the convert */ if (w1_strong_pullup == 2 || (!external_power && w1_strong_pullup)) w1_next_pullup(dev, tm); w1_write_8(dev, W1_CONVERT_TEMP); if (external_power) { mutex_unlock(&dev->bus_mutex); sleep_rem = msleep_interruptible(tm); if (sleep_rem != 0) { ret = -EINTR; goto dec_refcnt; } ret = mutex_lock_interruptible(&dev->bus_mutex); if (ret != 0) goto dec_refcnt; } else if (!w1_strong_pullup) { sleep_rem = msleep_interruptible(tm); if (sleep_rem != 0) { ret = -EINTR; goto mt_unlock; } } if (!reset_select_slave(sl)) { w1_write_8(dev, W1_READ_SCRATCHPAD); count = w1_read_block(dev, info->rom, 9); if (count != 9) { dev_warn(device, "w1_read_block() " "returned %u instead of 9.\n", count); } info->crc = w1_calc_crc8(info->rom, 8); if (info->rom[8] == info->crc) info->verdict = 1; } } if (info->verdict) break; } mt_unlock: mutex_unlock(&dev->bus_mutex); dec_refcnt: atomic_dec(THERM_REFCNT(family_data)); error: return ret; } static int read_scratchpad(struct w1_slave *sl, struct therm_info *info) { struct w1_master *dev_master = sl->master; int max_trying = W1_THERM_MAX_TRY; int ret = -ENODEV; info->verdict = 0; if (!sl->family_data) goto error; memset(info->rom, 0, sizeof(info->rom)); /* prevent the slave from going away in sleep */ atomic_inc(THERM_REFCNT(sl->family_data)); if (!bus_mutex_lock(&dev_master->bus_mutex)) { ret = -EAGAIN; /* Didn't acquire the mutex */ goto dec_refcnt; } while (max_trying-- && ret) { /* ret should be 0 */ /* safe version to select slave */ if (!reset_select_slave(sl)) { u8 nb_bytes_read; w1_write_8(dev_master, W1_READ_SCRATCHPAD); nb_bytes_read = w1_read_block(dev_master, info->rom, 9); if (nb_bytes_read != 9) { dev_warn(&sl->dev, "w1_read_block(): returned %u instead of 9.\n", nb_bytes_read); ret = -EIO; } info->crc = w1_calc_crc8(info->rom, 8); if (info->rom[8] == info->crc) { info->verdict = 1; ret = 0; } else ret = -EIO; /* CRC not checked */ } } mutex_unlock(&dev_master->bus_mutex); dec_refcnt: atomic_dec(THERM_REFCNT(sl->family_data)); error: return ret; } static int write_scratchpad(struct w1_slave *sl, const u8 *data, u8 nb_bytes) { struct w1_master *dev_master = sl->master; int max_trying = W1_THERM_MAX_TRY; int ret = -ENODEV; if (!sl->family_data) goto error; /* prevent the slave from going away in sleep */ atomic_inc(THERM_REFCNT(sl->family_data)); if (!bus_mutex_lock(&dev_master->bus_mutex)) { ret = -EAGAIN; /* Didn't acquire the mutex */ goto dec_refcnt; } while (max_trying-- && ret) { /* ret should be 0 */ /* safe version to select slave */ if (!reset_select_slave(sl)) { w1_write_8(dev_master, W1_WRITE_SCRATCHPAD); w1_write_block(dev_master, data, nb_bytes); ret = 0; } } mutex_unlock(&dev_master->bus_mutex); dec_refcnt: atomic_dec(THERM_REFCNT(sl->family_data)); error: return ret; } static inline int w1_therm_eeprom(struct device *device) { struct w1_slave *sl = dev_to_w1_slave(device); struct w1_master *dev = sl->master; u8 rom[9], external_power; int ret, max_trying = 10; u8 *family_data = sl->family_data; if (!sl->family_data) { ret = -ENODEV; goto error; } /* prevent the slave from going away in sleep */ atomic_inc(THERM_REFCNT(family_data)); ret = mutex_lock_interruptible(&dev->bus_mutex); if (ret != 0) goto dec_refcnt; memset(rom, 0, sizeof(rom)); while (max_trying--) { if (!reset_select_slave(sl)) { unsigned int tm = 10; unsigned long sleep_rem; /* check if in parasite mode */ w1_write_8(dev, W1_READ_PSUPPLY); external_power = w1_read_8(dev); if (reset_select_slave(sl)) continue; /* 10ms strong pullup/delay after the copy command */ if (w1_strong_pullup == 2 || (!external_power && w1_strong_pullup)) w1_next_pullup(dev, tm); w1_write_8(dev, W1_COPY_SCRATCHPAD); if (external_power) { mutex_unlock(&dev->bus_mutex); sleep_rem = msleep_interruptible(tm); if (sleep_rem != 0) { ret = -EINTR; goto dec_refcnt; } ret = mutex_lock_interruptible(&dev->bus_mutex); if (ret != 0) goto dec_refcnt; } else if (!w1_strong_pullup) { sleep_rem = msleep_interruptible(tm); if (sleep_rem != 0) { ret = -EINTR; goto mt_unlock; } } break; } } mt_unlock: mutex_unlock(&dev->bus_mutex); dec_refcnt: atomic_dec(THERM_REFCNT(family_data)); error: return ret; } static int read_powermode(struct w1_slave *sl) { struct w1_master *dev_master = sl->master; int max_trying = W1_THERM_MAX_TRY; int ret = -ENODEV; if (!sl->family_data) goto error; /* prevent the slave from going away in sleep */ atomic_inc(THERM_REFCNT(sl->family_data)); if (!bus_mutex_lock(&dev_master->bus_mutex)) { ret = -EAGAIN; /* Didn't acquire the mutex */ goto dec_refcnt; } while ((max_trying--) && (ret < 0)) { /* safe version to select slave */ if (!reset_select_slave(sl)) { w1_write_8(dev_master, W1_READ_PSUPPLY); /* * Emit a read time slot and read only one bit, * 1 is externally powered, * 0 is parasite powered */ ret = w1_touch_bit(dev_master, 1); /* ret should be either 1 either 0 */ } } mutex_unlock(&dev_master->bus_mutex); dec_refcnt: atomic_dec(THERM_REFCNT(sl->family_data)); error: return ret; } /* Sysfs Interface definition */ static ssize_t w1_slave_show(struct device *device, struct device_attribute *attr, char *buf) { struct w1_slave *sl = dev_to_w1_slave(device); struct therm_info info; u8 *family_data = sl->family_data; int ret, i; ssize_t c = PAGE_SIZE; u8 fid = sl->family->fid; ret = read_therm(device, sl, &info); if (ret) return ret; for (i = 0; i < 9; ++i) c -= snprintf(buf + PAGE_SIZE - c, c, "%02x ", info.rom[i]); c -= snprintf(buf + PAGE_SIZE - c, c, ": crc=%02x %s\n", info.crc, (info.verdict) ? "YES" : "NO"); if (info.verdict) memcpy(family_data, info.rom, sizeof(info.rom)); else dev_warn(device, "Read failed CRC check\n"); for (i = 0; i < 9; ++i) c -= snprintf(buf + PAGE_SIZE - c, c, "%02x ", ((u8 *)family_data)[i]); c -= snprintf(buf + PAGE_SIZE - c, c, "t=%d\n", w1_convert_temp(info.rom, fid)); ret = PAGE_SIZE - c; return ret; } static ssize_t w1_slave_store(struct device *device, struct device_attribute *attr, const char *buf, size_t size) { int val, ret = 0; struct w1_slave *sl = dev_to_w1_slave(device); ret = kstrtoint(buf, 10, &val); /* converting user entry to int */ if (ret) { /* conversion error */ dev_info(device, "%s: conversion error. err= %d\n", __func__, ret); return size; /* return size to avoid call back again */ } if ((!sl->family_data) || (!SLAVE_SPECIFIC_FUNC(sl))) { dev_info(device, "%s: Device not supported by the driver\n", __func__); return size; /* No device family */ } if (val == 0) /* val=0 : trigger a EEPROM save */ ret = SLAVE_SPECIFIC_FUNC(sl)->eeprom(device); else { if (SLAVE_SPECIFIC_FUNC(sl)->set_resolution) ret = SLAVE_SPECIFIC_FUNC(sl)->set_resolution(sl, val); } if (ret) { dev_info(device, "%s: writing error %d\n", __func__, ret); /* return size to avoid call back again */ } else SLAVE_RESOLUTION(sl) = val; return size; /* always return size to avoid infinite calling */ } static ssize_t ext_power_show(struct device *device, struct device_attribute *attr, char *buf) { struct w1_slave *sl = dev_to_w1_slave(device); if (!sl->family_data) { dev_info(device, "%s: Device not supported by the driver\n", __func__); return 0; /* No device family */ } /* Getting the power mode of the device {external, parasite} */ SLAVE_POWERMODE(sl) = read_powermode(sl); if (SLAVE_POWERMODE(sl) < 0) { dev_dbg(device, "%s: Power_mode may be corrupted. err=%d\n", __func__, SLAVE_POWERMODE(sl)); } return sprintf(buf, "%d\n", SLAVE_POWERMODE(sl)); } static ssize_t resolution_show(struct device *device, struct device_attribute *attr, char *buf) { struct w1_slave *sl = dev_to_w1_slave(device); if ((!sl->family_data) || (!SLAVE_SPECIFIC_FUNC(sl))) { dev_info(device, "%s: Device not supported by the driver\n", __func__); return 0; /* No device family */ } /* get the correct function depending on the device */ SLAVE_RESOLUTION(sl) = SLAVE_SPECIFIC_FUNC(sl)->get_resolution(sl); if (SLAVE_RESOLUTION(sl) < 0) { dev_dbg(device, "%s: Resolution may be corrupted. err=%d\n", __func__, SLAVE_RESOLUTION(sl)); } return sprintf(buf, "%d\n", SLAVE_RESOLUTION(sl)); } static ssize_t resolution_store(struct device *device, struct device_attribute *attr, const char *buf, size_t size) { struct w1_slave *sl = dev_to_w1_slave(device); int val; int ret = 0; ret = kstrtoint(buf, 10, &val); /* converting user entry to int */ if (ret) { /* conversion error */ dev_info(device, "%s: conversion error. err= %d\n", __func__, ret); return size; /* return size to avoid call back again */ } if ((!sl->family_data) || (!SLAVE_SPECIFIC_FUNC(sl))) { dev_info(device, "%s: Device not supported by the driver\n", __func__); return size; /* No device family */ } /* * Don't deal with the val enterd by user, * only device knows what is correct or not */ /* get the correct function depending on the device */ ret = SLAVE_SPECIFIC_FUNC(sl)->set_resolution(sl, val); if (ret) { dev_info(device, "%s: writing error %d\n", __func__, ret); /* return size to avoid call back again */ } else SLAVE_RESOLUTION(sl) = val; return size; } #if IS_REACHABLE(CONFIG_HWMON) static int w1_read_temp(struct device *device, u32 attr, int channel, long *val) { struct w1_slave *sl = dev_get_drvdata(device); struct therm_info info; u8 fid = sl->family->fid; int ret; switch (attr) { case hwmon_temp_input: ret = read_therm(device, sl, &info); if (ret) return ret; if (!info.verdict) { ret = -EIO; return ret; } *val = w1_convert_temp(info.rom, fid); ret = 0; break; default: ret = -EOPNOTSUPP; break; } return ret; } #endif #define W1_42_CHAIN 0x99 #define W1_42_CHAIN_OFF 0x3C #define W1_42_CHAIN_OFF_INV 0xC3 #define W1_42_CHAIN_ON 0x5A #define W1_42_CHAIN_ON_INV 0xA5 #define W1_42_CHAIN_DONE 0x96 #define W1_42_CHAIN_DONE_INV 0x69 #define W1_42_COND_READ 0x0F #define W1_42_SUCCESS_CONFIRM_BYTE 0xAA #define W1_42_FINISHED_BYTE 0xFF static ssize_t w1_seq_show(struct device *device, struct device_attribute *attr, char *buf) { struct w1_slave *sl = dev_to_w1_slave(device); ssize_t c = PAGE_SIZE; int rv; int i; u8 ack; u64 rn; struct w1_reg_num *reg_num; int seq = 0; mutex_lock(&sl->master->bus_mutex); /* Place all devices in CHAIN state */ if (w1_reset_bus(sl->master)) goto error; w1_write_8(sl->master, W1_SKIP_ROM); w1_write_8(sl->master, W1_42_CHAIN); w1_write_8(sl->master, W1_42_CHAIN_ON); w1_write_8(sl->master, W1_42_CHAIN_ON_INV); msleep(sl->master->pullup_duration); /* check for acknowledgment */ ack = w1_read_8(sl->master); if (ack != W1_42_SUCCESS_CONFIRM_BYTE) goto error; /* In case the bus fails to send 0xFF, limit */ for (i = 0; i <= 64; i++) { if (w1_reset_bus(sl->master)) goto error; w1_write_8(sl->master, W1_42_COND_READ); rv = w1_read_block(sl->master, (u8 *)&rn, 8); reg_num = (struct w1_reg_num *) &rn; if (reg_num->family == W1_42_FINISHED_BYTE) break; if (sl->reg_num.id == reg_num->id) seq = i; w1_write_8(sl->master, W1_42_CHAIN); w1_write_8(sl->master, W1_42_CHAIN_DONE); w1_write_8(sl->master, W1_42_CHAIN_DONE_INV); w1_read_block(sl->master, &ack, sizeof(ack)); /* check for acknowledgment */ ack = w1_read_8(sl->master); if (ack != W1_42_SUCCESS_CONFIRM_BYTE) goto error; } /* Exit from CHAIN state */ if (w1_reset_bus(sl->master)) goto error; w1_write_8(sl->master, W1_SKIP_ROM); w1_write_8(sl->master, W1_42_CHAIN); w1_write_8(sl->master, W1_42_CHAIN_OFF); w1_write_8(sl->master, W1_42_CHAIN_OFF_INV); /* check for acknowledgment */ ack = w1_read_8(sl->master); if (ack != W1_42_SUCCESS_CONFIRM_BYTE) goto error; mutex_unlock(&sl->master->bus_mutex); c -= snprintf(buf + PAGE_SIZE - c, c, "%d\n", seq); return PAGE_SIZE - c; error: mutex_unlock(&sl->master->bus_mutex); return -EIO; } static int __init w1_therm_init(void) { int err, i; for (i = 0; i < ARRAY_SIZE(w1_therm_families); ++i) { err = w1_register_family(w1_therm_families[i].f); if (err) w1_therm_families[i].broken = 1; } return 0; } static void __exit w1_therm_fini(void) { int i; for (i = 0; i < ARRAY_SIZE(w1_therm_families); ++i) if (!w1_therm_families[i].broken) w1_unregister_family(w1_therm_families[i].f); } module_init(w1_therm_init); module_exit(w1_therm_fini); MODULE_AUTHOR("Evgeniy Polyakov "); MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol, temperature family."); MODULE_LICENSE("GPL"); MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS18S20)); MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS1822)); MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS18B20)); MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS1825)); MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS28EA00));