// 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 #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); /* Counter for devices supporting bulk reading */ static u16 bulk_read_device_counter; /* =0 as per C standard */ /* This command should be in public header w1.h but is not */ #define W1_RECALL_EEPROM 0xB8 /* Nb of try for an operation */ #define W1_THERM_MAX_TRY 5 /* ms delay to retry bus mutex */ #define W1_THERM_RETRY_DELAY 20 /* delay in ms to write in EEPROM */ #define W1_THERM_EEPROM_WRITE_DELAY 10 #define EEPROM_CMD_WRITE "save" /* cmd for write eeprom sysfs */ #define EEPROM_CMD_READ "restore" /* cmd for read eeprom sysfs */ #define BULK_TRIGGER_CMD "trigger" /* cmd to trigger a bulk read */ #define MIN_TEMP -55 /* min temperature that can be measured */ #define MAX_TEMP 125 /* max temperature that can be measured */ /* Allowed values for sysfs conv_time attribute */ #define CONV_TIME_DEFAULT 0 #define CONV_TIME_MEASURE 1 /* Bits in sysfs "features" value */ #define W1_THERM_CHECK_RESULT 1 /* Enable conversion success check */ #define W1_THERM_POLL_COMPLETION 2 /* Poll for conversion completion */ #define W1_THERM_FEATURES_MASK 3 /* All values mask */ /* Poll period in milliseconds. Should be less then a shortest operation on the device */ #define W1_POLL_PERIOD 32 #define W1_POLL_CONVERT_TEMP 2000 /* Timeout for W1_CONVERT_TEMP, ms */ #define W1_POLL_RECALL_EEPROM 500 /* Timeout for W1_RECALL_EEPROM, ms*/ /* Masks for resolution functions, work with all devices */ /* Bit mask for config register for all devices, bits 7,6,5 */ #define W1_THERM_RESOLUTION_MASK 0xE0 /* Bit offset of resolution in config register for all devices */ #define W1_THERM_RESOLUTION_SHIFT 5 /* Bit offset of resolution in config register for all devices */ #define W1_THERM_RESOLUTION_SHIFT 5 /* Add this to bit value to get resolution */ #define W1_THERM_RESOLUTION_MIN 9 /* Maximum allowed value */ #define W1_THERM_RESOLUTION_MAX 14 /* 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 conv_time_override of the sl slave * always test family data existence before using this macro */ #define SLAVE_CONV_TIME_OVERRIDE(sl) \ (((struct w1_therm_family_data *)(sl->family_data))->conv_time_override) /* * return the features of the sl slave * always test family data existence before using this macro */ #define SLAVE_FEATURES(sl) \ (((struct w1_therm_family_data *)(sl->family_data))->features) /* * return whether or not a converT command has been issued to the slave * * 0: no bulk read is pending * * -1: conversion is in progress * * 1: conversion done, result to be read */ #define SLAVE_CONVERT_TRIGGERED(sl) \ (((struct w1_therm_family_data *)(sl->family_data))->convert_triggered) /* 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 * @get_conversion_time: pointer to the device conversion time function * @set_resolution: pointer to the device set_resolution function * @get_resolution: pointer to the device get_resolution function * @write_data: pointer to the device writing function (2 or 3 bytes) * @bulk_read: true if device family support bulk read, false otherwise */ struct w1_therm_family_converter { u8 broken; u16 reserved; struct w1_family *f; int (*convert)(u8 rom[9]); int (*get_conversion_time)(struct w1_slave *sl); int (*set_resolution)(struct w1_slave *sl, int val); int (*get_resolution)(struct w1_slave *sl); int (*write_data)(struct w1_slave *sl, const u8 *data); bool bulk_read; }; /** * 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 * @convert_triggered: conversion state of the device * @conv_time_override: user selected conversion time or CONV_TIME_DEFAULT * @features: bit mask - enable temperature validity check, poll for completion * @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; int convert_triggered; int conv_time_override; unsigned int features; 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); /** * convert_t() - Query the device for temperature conversion and read * @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 convert_t(struct w1_slave *sl, struct therm_info *info); /** * 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); /** * copy_scratchpad() - Copy the content of scratchpad in device EEPROM * @sl: slave involved * * Return: 0 if success, -kernel error code otherwise */ static int copy_scratchpad(struct w1_slave *sl); /** * recall_eeprom() - Restore EEPROM data to device RAM * @sl: slave involved * * Return: 0 if success, -kernel error code otherwise */ static int recall_eeprom(struct w1_slave *sl); /** * 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); /** * trigger_bulk_read() - function to trigger a bulk read on the bus * @dev_master: the device master of the bus * * Send a SKIP ROM follow by a CONVERT T command on the bus. * It also set the status flag in each slave &struct w1_therm_family_data * to signal that a conversion is in progress. * * Return: 0 if success, -kernel error code otherwise */ static int trigger_bulk_read(struct w1_master *dev_master); /* 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 temperature_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); static ssize_t eeprom_cmd_store(struct device *device, struct device_attribute *attr, const char *buf, size_t size); static ssize_t alarms_store(struct device *device, struct device_attribute *attr, const char *buf, size_t size); static ssize_t alarms_show(struct device *device, struct device_attribute *attr, char *buf); static ssize_t therm_bulk_read_store(struct device *device, struct device_attribute *attr, const char *buf, size_t size); static ssize_t therm_bulk_read_show(struct device *device, struct device_attribute *attr, char *buf); static ssize_t conv_time_show(struct device *device, struct device_attribute *attr, char *buf); static ssize_t conv_time_store(struct device *device, struct device_attribute *attr, const char *buf, size_t size); static ssize_t features_show(struct device *device, struct device_attribute *attr, char *buf); static ssize_t features_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(temperature); static DEVICE_ATTR_RO(ext_power); static DEVICE_ATTR_RW(resolution); static DEVICE_ATTR_WO(eeprom_cmd); static DEVICE_ATTR_RW(alarms); static DEVICE_ATTR_RW(conv_time); static DEVICE_ATTR_RW(features); static DEVICE_ATTR_RW(therm_bulk_read); /* attribut at master level */ /* 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_temperature.attr, &dev_attr_ext_power.attr, &dev_attr_resolution.attr, &dev_attr_eeprom_cmd.attr, &dev_attr_alarms.attr, &dev_attr_conv_time.attr, &dev_attr_features.attr, NULL, }; static struct attribute *w1_ds18s20_attrs[] = { &dev_attr_w1_slave.attr, &dev_attr_temperature.attr, &dev_attr_ext_power.attr, &dev_attr_eeprom_cmd.attr, &dev_attr_alarms.attr, &dev_attr_conv_time.attr, &dev_attr_features.attr, NULL, }; static struct attribute *w1_ds28ea00_attrs[] = { &dev_attr_w1_slave.attr, &dev_attr_w1_seq.attr, &dev_attr_temperature.attr, &dev_attr_ext_power.attr, &dev_attr_resolution.attr, &dev_attr_eeprom_cmd.attr, &dev_attr_alarms.attr, &dev_attr_conv_time.attr, &dev_attr_features.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 struct hwmon_channel_info * const w1_info[] = { HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT), 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 const 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 const 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 const 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 */ static inline int w1_DS18B20_convert_time(struct w1_slave *sl) { int ret; if (!sl->family_data) return -ENODEV; /* device unknown */ if (SLAVE_CONV_TIME_OVERRIDE(sl) != CONV_TIME_DEFAULT) return SLAVE_CONV_TIME_OVERRIDE(sl); /* Return the conversion time, depending on resolution, * select maximum conversion time among all compatible devices */ switch (SLAVE_RESOLUTION(sl)) { case 9: ret = 95; break; case 10: ret = 190; break; case 11: ret = 375; break; case 12: ret = 750; break; case 13: ret = 850; /* GX20MH01 only. Datasheet says 500ms, but that's not enough. */ break; case 14: ret = 1600; /* GX20MH01 only. Datasheet says 1000ms - not enough */ break; default: ret = 750; } return ret; } static inline int w1_DS18S20_convert_time(struct w1_slave *sl) { if (!sl->family_data) return -ENODEV; /* device unknown */ if (SLAVE_CONV_TIME_OVERRIDE(sl) == CONV_TIME_DEFAULT) return 750; /* default for DS18S20 */ else return SLAVE_CONV_TIME_OVERRIDE(sl); } static inline int w1_DS1825_convert_time(struct w1_slave *sl) { int ret; if (!sl->family_data) return -ENODEV; /* device unknown */ if (SLAVE_CONV_TIME_OVERRIDE(sl) != CONV_TIME_DEFAULT) return SLAVE_CONV_TIME_OVERRIDE(sl); /* Return the conversion time, depending on resolution, * select maximum conversion time among all compatible devices */ switch (SLAVE_RESOLUTION(sl)) { case 9: ret = 95; break; case 10: ret = 190; break; case 11: ret = 375; break; case 12: ret = 750; break; case 14: ret = 100; /* MAX31850 only. Datasheet says 100ms */ break; default: ret = 750; } return ret; } 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; struct therm_info info, info2; /* DS18B20 resolution is 9 to 12 bits */ /* GX20MH01 resolution is 9 to 14 bits */ /* MAX31850 resolution is fixed 14 bits */ if (val < W1_THERM_RESOLUTION_MIN || val > W1_THERM_RESOLUTION_MAX) return -EINVAL; /* Calc bit value from resolution */ val = (val - W1_THERM_RESOLUTION_MIN) << W1_THERM_RESOLUTION_SHIFT; /* * Read the scratchpad to change only the required bits * (bit5 & bit 6 from byte 4) */ ret = read_scratchpad(sl, &info); if (ret) return ret; info.rom[4] &= ~W1_THERM_RESOLUTION_MASK; info.rom[4] |= val; /* Write data in the device RAM */ ret = w1_DS18B20_write_data(sl, info.rom + 2); if (ret) return ret; /* Have to read back the resolution to verify an actual value * GX20MH01 and DS18B20 are indistinguishable by family number, but resolutions differ * Some DS18B20 clones don't support resolution change */ ret = read_scratchpad(sl, &info2); if (ret) /* Scratchpad read fail */ return ret; if ((info2.rom[4] & W1_THERM_RESOLUTION_MASK) == (info.rom[4] & W1_THERM_RESOLUTION_MASK)) return 0; /* Resolution verify error */ return -EIO; } static inline int w1_DS18B20_get_resolution(struct w1_slave *sl) { int ret; int resolution; struct therm_info info; ret = read_scratchpad(sl, &info); if (ret) return ret; resolution = ((info.rom[4] & W1_THERM_RESOLUTION_MASK) >> W1_THERM_RESOLUTION_SHIFT) + W1_THERM_RESOLUTION_MIN; /* GX20MH01 has one special case: * >=14 means 14 bits when getting resolution from bit value. * MAX31850 delivers fixed 15 and has 14 bits. * Other devices have no more then 12 bits. */ if (resolution > W1_THERM_RESOLUTION_MAX) resolution = W1_THERM_RESOLUTION_MAX; return resolution; } /** * 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]) { u16 bv; s16 t; /* Signed 16-bit value to unsigned, cpu order */ bv = le16_to_cpup((__le16 *)rom); /* Config register bit R2 = 1 - GX20MH01 in 13 or 14 bit resolution mode */ if (rom[4] & 0x80) { /* Insert two temperature bits from config register */ /* Avoid arithmetic shift of signed value */ bv = (bv << 2) | (rom[4] & 3); t = (s16) bv; /* Degrees, lowest bit is 2^-6 */ return (int)t * 1000 / 64; /* Sign-extend to int; millidegrees */ } t = (s16)bv; /* Degrees, lowest bit is 2^-4 */ return (int)t * 1000 / 16; /* Sign-extend to int; millidegrees */ } /** * 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]) { pr_debug("%s: Invalid argument for conversion\n", __func__); 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; } /** * w1_DS1825_convert_temp() - temperature computation for DS1825 * @rom: data read from device RAM (8 data bytes + 1 CRC byte) * * Can be called for any DS1825 compliant device. * Is used by MAX31850, too * * Return: value in millidegrees Celsius. */ static inline int w1_DS1825_convert_temp(u8 rom[9]) { u16 bv; s16 t; /* Signed 16-bit value to unsigned, cpu order */ bv = le16_to_cpup((__le16 *)rom); /* Config register bit 7 = 1 - MA31850 found, 14 bit resolution */ if (rom[4] & 0x80) { /* Mask out bits 0 (Fault) and 1 (Reserved) */ /* Avoid arithmetic shift of signed value */ bv = (bv & 0xFFFC); /* Degrees, lowest 4 bits are 2^-1, 2^-2 and 2 zero bits */ } t = (s16)bv; /* Degrees, lowest bit is 2^-4 */ return (int)t * 1000 / 16; /* Sign-extend to int; millidegrees */ } /* Device capability description */ /* GX20MH01 device shares family number and structure with DS18B20 */ static struct w1_therm_family_converter w1_therm_families[] = { { .f = &w1_therm_family_DS18S20, .convert = w1_DS18S20_convert_temp, .get_conversion_time = w1_DS18S20_convert_time, .set_resolution = NULL, /* no config register */ .get_resolution = NULL, /* no config register */ .write_data = w1_DS18S20_write_data, .bulk_read = true }, { .f = &w1_therm_family_DS1822, .convert = w1_DS18B20_convert_temp, .get_conversion_time = w1_DS18B20_convert_time, .set_resolution = w1_DS18B20_set_resolution, .get_resolution = w1_DS18B20_get_resolution, .write_data = w1_DS18B20_write_data, .bulk_read = true }, { /* Also used for GX20MH01 */ .f = &w1_therm_family_DS18B20, .convert = w1_DS18B20_convert_temp, .get_conversion_time = w1_DS18B20_convert_time, .set_resolution = w1_DS18B20_set_resolution, .get_resolution = w1_DS18B20_get_resolution, .write_data = w1_DS18B20_write_data, .bulk_read = true }, { .f = &w1_therm_family_DS28EA00, .convert = w1_DS18B20_convert_temp, .get_conversion_time = w1_DS18B20_convert_time, .set_resolution = w1_DS18B20_set_resolution, .get_resolution = w1_DS18B20_get_resolution, .write_data = w1_DS18B20_write_data, .bulk_read = false }, { /* Also used for MAX31850 */ .f = &w1_therm_family_DS1825, .convert = w1_DS1825_convert_temp, .get_conversion_time = w1_DS1825_convert_time, .set_resolution = w1_DS18B20_set_resolution, .get_resolution = w1_DS18B20_get_resolution, .write_data = w1_DS18B20_write_data, .bulk_read = true } }; /* 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; } /** * check_family_data() - Check if family data and specific functions are present * @sl: W1 device data * * Return: 0 - OK, negative value - error */ static int check_family_data(struct w1_slave *sl) { if ((!sl->family_data) || (!SLAVE_SPECIFIC_FUNC(sl))) { dev_info(&sl->dev, "%s: Device is not supported by the driver\n", __func__); return -EINVAL; /* No device family */ } return 0; } /** * bulk_read_support() - check if slave support bulk read * @sl: device to check the ability * * Return: true if bulk read is supported, false if not or error */ static inline bool bulk_read_support(struct w1_slave *sl) { if (SLAVE_SPECIFIC_FUNC(sl)) return SLAVE_SPECIFIC_FUNC(sl)->bulk_read; dev_info(&sl->dev, "%s: Device not supported by the driver\n", __func__); return false; /* No device family */ } /** * conversion_time() - get the Tconv for the slave * @sl: device to get the conversion time * * On device supporting resolution settings, conversion time depend * on the resolution setting. This helper function get the slave timing, * depending on its current setting. * * Return: conversion time in ms, negative values are kernel error code */ static inline int conversion_time(struct w1_slave *sl) { if (SLAVE_SPECIFIC_FUNC(sl)) return SLAVE_SPECIFIC_FUNC(sl)->get_conversion_time(sl); dev_info(&sl->dev, "%s: Device not supported by the driver\n", __func__); return -ENODEV; /* No device family */ } /** * temperature_from_RAM() - Convert the read info to temperature * @sl: device that sent the RAM data * @rom: read value on the slave device RAM * * Device dependent, the function bind the correct computation method. * * Return: temperature in 1/1000degC, 0 on error. */ static inline int temperature_from_RAM(struct w1_slave *sl, u8 rom[9]) { if (SLAVE_SPECIFIC_FUNC(sl)) return SLAVE_SPECIFIC_FUNC(sl)->convert(rom); dev_info(&sl->dev, "%s: Device not supported by the driver\n", __func__); return 0; /* No device family */ } /** * int_to_short() - Safe casting of int to short * * @i: integer to be converted to short * * Device register use 1 byte to store signed integer. * This helper function convert the int in a signed short, * using the min/max values that device can measure as limits. * min/max values are defined by macro. * * Return: a short in the range of min/max value */ static inline s8 int_to_short(int i) { /* Prepare to cast to short by eliminating out of range values */ i = clamp(i, MIN_TEMP, MAX_TEMP); return (s8) i; } /* 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; if (bulk_read_support(sl)) { /* * add the sys entry to trigger bulk_read * at master level only the 1st time */ if (!bulk_read_device_counter) { int err = device_create_file(&sl->master->dev, &dev_attr_therm_bulk_read); if (err) dev_warn(&sl->dev, "%s: Device has been added, but bulk read is unavailable. err=%d\n", __func__, err); } /* Increment the counter */ bulk_read_device_counter++; } /* 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)); } } /* Finally initialize convert_triggered flag */ SLAVE_CONVERT_TRIGGERED(sl) = 0; return 0; } static void w1_therm_remove_slave(struct w1_slave *sl) { int refcnt = atomic_sub_return(1, THERM_REFCNT(sl->family_data)); if (bulk_read_support(sl)) { bulk_read_device_counter--; /* Delete the entry if no more device support the feature */ if (!bulk_read_device_counter) device_remove_file(&sl->master->dev, &dev_attr_therm_bulk_read); } 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; } /** * w1_poll_completion - Poll for operation completion, with timeout * @dev_master: the device master of the bus * @tout_ms: timeout in milliseconds * * The device is answering 0's while an operation is in progress and 1's after it completes * Timeout may happen if the previous command was not recognised due to a line noise * * Return: 0 - OK, negative error - timeout */ static int w1_poll_completion(struct w1_master *dev_master, int tout_ms) { int i; for (i = 0; i < tout_ms/W1_POLL_PERIOD; i++) { /* Delay is before poll, for device to recognize a command */ msleep(W1_POLL_PERIOD); /* Compare all 8 bits to mitigate a noise on the bus */ if (w1_read_8(dev_master) == 0xFF) break; } if (i == tout_ms/W1_POLL_PERIOD) return -EIO; return 0; } static int convert_t(struct w1_slave *sl, struct therm_info *info) { struct w1_master *dev_master = sl->master; int max_trying = W1_THERM_MAX_TRY; int t_conv; int ret = -ENODEV; bool strong_pullup; if (!sl->family_data) goto error; strong_pullup = (w1_strong_pullup == 2 || (!SLAVE_POWERMODE(sl) && w1_strong_pullup)); if (strong_pullup && SLAVE_FEATURES(sl) & W1_THERM_POLL_COMPLETION) { dev_warn(&sl->dev, "%s: Disabling W1_THERM_POLL_COMPLETION in parasite power mode.\n", __func__); SLAVE_FEATURES(sl) &= ~W1_THERM_POLL_COMPLETION; } /* get conversion duration device and id dependent */ t_conv = conversion_time(sl); 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 */ info->verdict = 0; info->crc = 0; /* safe version to select slave */ if (!reset_select_slave(sl)) { unsigned long sleep_rem; /* 750ms strong pullup (or delay) after the convert */ if (strong_pullup) w1_next_pullup(dev_master, t_conv); w1_write_8(dev_master, W1_CONVERT_TEMP); if (SLAVE_FEATURES(sl) & W1_THERM_POLL_COMPLETION) { ret = w1_poll_completion(dev_master, W1_POLL_CONVERT_TEMP); if (ret) { dev_dbg(&sl->dev, "%s: Timeout\n", __func__); goto mt_unlock; } mutex_unlock(&dev_master->bus_mutex); } else if (!strong_pullup) { /*no device need pullup */ sleep_rem = msleep_interruptible(t_conv); if (sleep_rem != 0) { ret = -EINTR; goto mt_unlock; } mutex_unlock(&dev_master->bus_mutex); } else { /*some device need pullup */ mutex_unlock(&dev_master->bus_mutex); sleep_rem = msleep_interruptible(t_conv); if (sleep_rem != 0) { ret = -EINTR; goto dec_refcnt; } } ret = read_scratchpad(sl, info); /* If enabled, check for conversion success */ if ((SLAVE_FEATURES(sl) & W1_THERM_CHECK_RESULT) && (info->rom[6] == 0xC) && ((info->rom[1] == 0x5 && info->rom[0] == 0x50) || (info->rom[1] == 0x7 && info->rom[0] == 0xFF)) ) { /* Invalid reading (scratchpad byte 6 = 0xC) * due to insufficient conversion time * or power failure. */ ret = -EIO; } goto dec_refcnt; } } mt_unlock: mutex_unlock(&dev_master->bus_mutex); dec_refcnt: atomic_dec(THERM_REFCNT(sl->family_data)); error: return ret; } static int conv_time_measure(struct w1_slave *sl, int *conv_time) { struct therm_info inf, *info = &inf; struct w1_master *dev_master = sl->master; int max_trying = W1_THERM_MAX_TRY; int ret = -ENODEV; bool strong_pullup; if (!sl->family_data) goto error; strong_pullup = (w1_strong_pullup == 2 || (!SLAVE_POWERMODE(sl) && w1_strong_pullup)); if (strong_pullup) { pr_info("%s: Measure with strong_pullup is not supported.\n", __func__); return -EINVAL; } 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 */ info->verdict = 0; info->crc = 0; /* safe version to select slave */ if (!reset_select_slave(sl)) { int j_start, j_end; /*no device need pullup */ w1_write_8(dev_master, W1_CONVERT_TEMP); j_start = jiffies; ret = w1_poll_completion(dev_master, W1_POLL_CONVERT_TEMP); if (ret) { dev_dbg(&sl->dev, "%s: Timeout\n", __func__); goto mt_unlock; } j_end = jiffies; /* 1.2x increase for variation and changes over temperature range */ *conv_time = jiffies_to_msecs(j_end-j_start)*12/10; pr_debug("W1 Measure complete, conv_time = %d, HZ=%d.\n", *conv_time, HZ); if (*conv_time <= CONV_TIME_MEASURE) { ret = -EIO; goto mt_unlock; } mutex_unlock(&dev_master->bus_mutex); ret = read_scratchpad(sl, info); goto dec_refcnt; } } mt_unlock: mutex_unlock(&dev_master->bus_mutex); dec_refcnt: atomic_dec(THERM_REFCNT(sl->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 int copy_scratchpad(struct w1_slave *sl) { struct w1_master *dev_master = sl->master; int max_trying = W1_THERM_MAX_TRY; int t_write, ret = -ENODEV; bool strong_pullup; if (!sl->family_data) goto error; t_write = W1_THERM_EEPROM_WRITE_DELAY; strong_pullup = (w1_strong_pullup == 2 || (!SLAVE_POWERMODE(sl) && w1_strong_pullup)); /* 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)) { unsigned long sleep_rem; /* 10ms strong pullup (or delay) after the convert */ if (strong_pullup) w1_next_pullup(dev_master, t_write); w1_write_8(dev_master, W1_COPY_SCRATCHPAD); if (strong_pullup) { sleep_rem = msleep_interruptible(t_write); if (sleep_rem != 0) { ret = -EINTR; goto mt_unlock; } } ret = 0; } } mt_unlock: mutex_unlock(&dev_master->bus_mutex); dec_refcnt: atomic_dec(THERM_REFCNT(sl->family_data)); error: return ret; } static int recall_eeprom(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) { /* ret should be 0 */ /* safe version to select slave */ if (!reset_select_slave(sl)) { w1_write_8(dev_master, W1_RECALL_EEPROM); ret = w1_poll_completion(dev_master, W1_POLL_RECALL_EEPROM); } } mutex_unlock(&dev_master->bus_mutex); dec_refcnt: atomic_dec(THERM_REFCNT(sl->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; } static int trigger_bulk_read(struct w1_master *dev_master) { struct w1_slave *sl = NULL; /* used to iterate through slaves */ int max_trying = W1_THERM_MAX_TRY; int t_conv = 0; int ret = -ENODEV; bool strong_pullup = false; /* * Check whether there are parasite powered device on the bus, * and compute duration of conversion for these devices * so we can apply a strong pullup if required */ list_for_each_entry(sl, &dev_master->slist, w1_slave_entry) { if (!sl->family_data) goto error; if (bulk_read_support(sl)) { int t_cur = conversion_time(sl); t_conv = max(t_cur, t_conv); strong_pullup = strong_pullup || (w1_strong_pullup == 2 || (!SLAVE_POWERMODE(sl) && w1_strong_pullup)); } } /* * t_conv is the max conversion time required on the bus * If its 0, no device support the bulk read feature */ if (!t_conv) goto error; if (!bus_mutex_lock(&dev_master->bus_mutex)) { ret = -EAGAIN; /* Didn't acquire the mutex */ goto error; } while ((max_trying--) && (ret < 0)) { /* ret should be either 0 */ if (!w1_reset_bus(dev_master)) { /* Just reset the bus */ unsigned long sleep_rem; w1_write_8(dev_master, W1_SKIP_ROM); if (strong_pullup) /* Apply pullup if required */ w1_next_pullup(dev_master, t_conv); w1_write_8(dev_master, W1_CONVERT_TEMP); /* set a flag to instruct that converT pending */ list_for_each_entry(sl, &dev_master->slist, w1_slave_entry) { if (bulk_read_support(sl)) SLAVE_CONVERT_TRIGGERED(sl) = -1; } if (strong_pullup) { /* some device need pullup */ sleep_rem = msleep_interruptible(t_conv); if (sleep_rem != 0) { ret = -EINTR; goto mt_unlock; } mutex_unlock(&dev_master->bus_mutex); } else { mutex_unlock(&dev_master->bus_mutex); sleep_rem = msleep_interruptible(t_conv); if (sleep_rem != 0) { ret = -EINTR; goto set_flag; } } ret = 0; goto set_flag; } } mt_unlock: mutex_unlock(&dev_master->bus_mutex); set_flag: /* set a flag to register convsersion is done */ list_for_each_entry(sl, &dev_master->slist, w1_slave_entry) { if (bulk_read_support(sl)) SLAVE_CONVERT_TRIGGERED(sl) = 1; } 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; if (bulk_read_support(sl)) { if (SLAVE_CONVERT_TRIGGERED(sl) < 0) { dev_dbg(device, "%s: Conversion in progress, retry later\n", __func__); return 0; } else if (SLAVE_CONVERT_TRIGGERED(sl) > 0) { /* A bulk read has been issued, read the device RAM */ ret = read_scratchpad(sl, &info); SLAVE_CONVERT_TRIGGERED(sl) = 0; } else ret = convert_t(sl, &info); } else ret = convert_t(sl, &info); if (ret < 0) { dev_dbg(device, "%s: Temperature data may be corrupted. err=%d\n", __func__, ret); return 0; } 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, "%s:Read failed CRC check\n", __func__); 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", temperature_from_RAM(sl, info.rom)); 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 = copy_scratchpad(sl); else { if (SLAVE_SPECIFIC_FUNC(sl)->set_resolution) ret = SLAVE_SPECIFIC_FUNC(sl)->set_resolution(sl, val); } if (ret) { dev_warn(device, "%s: Set resolution - error %d\n", __func__, ret); /* Propagate error to userspace */ return ret; } SLAVE_RESOLUTION(sl) = val; /* Reset the conversion time to default - it depends on resolution */ SLAVE_CONV_TIME_OVERRIDE(sl) = CONV_TIME_DEFAULT; return size; /* always return size to avoid infinite calling */ } static ssize_t temperature_show(struct device *device, struct device_attribute *attr, char *buf) { struct w1_slave *sl = dev_to_w1_slave(device); struct therm_info info; int ret = 0; 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 */ } if (bulk_read_support(sl)) { if (SLAVE_CONVERT_TRIGGERED(sl) < 0) { dev_dbg(device, "%s: Conversion in progress, retry later\n", __func__); return 0; } else if (SLAVE_CONVERT_TRIGGERED(sl) > 0) { /* A bulk read has been issued, read the device RAM */ ret = read_scratchpad(sl, &info); SLAVE_CONVERT_TRIGGERED(sl) = 0; } else ret = convert_t(sl, &info); } else ret = convert_t(sl, &info); if (ret < 0) { dev_dbg(device, "%s: Temperature data may be corrupted. err=%d\n", __func__, ret); return 0; } return sprintf(buf, "%d\n", temperature_from_RAM(sl, info.rom)); } 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) return ret; SLAVE_RESOLUTION(sl) = val; /* Reset the conversion time to default because it depends on resolution */ SLAVE_CONV_TIME_OVERRIDE(sl) = CONV_TIME_DEFAULT; return size; } static ssize_t eeprom_cmd_store(struct device *device, struct device_attribute *attr, const char *buf, size_t size) { struct w1_slave *sl = dev_to_w1_slave(device); int ret = -EINVAL; /* Invalid argument */ if (size == sizeof(EEPROM_CMD_WRITE)) { if (!strncmp(buf, EEPROM_CMD_WRITE, sizeof(EEPROM_CMD_WRITE)-1)) ret = copy_scratchpad(sl); } else if (size == sizeof(EEPROM_CMD_READ)) { if (!strncmp(buf, EEPROM_CMD_READ, sizeof(EEPROM_CMD_READ)-1)) ret = recall_eeprom(sl); } if (ret) dev_info(device, "%s: error in process %d\n", __func__, ret); return size; } static ssize_t alarms_show(struct device *device, struct device_attribute *attr, char *buf) { struct w1_slave *sl = dev_to_w1_slave(device); int ret; s8 th = 0, tl = 0; struct therm_info scratchpad; ret = read_scratchpad(sl, &scratchpad); if (!ret) { th = scratchpad.rom[2]; /* TH is byte 2 */ tl = scratchpad.rom[3]; /* TL is byte 3 */ } else { dev_info(device, "%s: error reading alarms register %d\n", __func__, ret); } return sprintf(buf, "%hd %hd\n", tl, th); } static ssize_t alarms_store(struct device *device, struct device_attribute *attr, const char *buf, size_t size) { struct w1_slave *sl = dev_to_w1_slave(device); struct therm_info info; u8 new_config_register[3]; /* array of data to be written */ int temp, ret; char *token = NULL; s8 tl, th; /* 1 byte per value + temp ring order */ char *p_args, *orig; p_args = orig = kmalloc(size, GFP_KERNEL); /* Safe string copys as buf is const */ if (!p_args) { dev_warn(device, "%s: error unable to allocate memory %d\n", __func__, -ENOMEM); return size; } strcpy(p_args, buf); /* Split string using space char */ token = strsep(&p_args, " "); if (!token) { dev_info(device, "%s: error parsing args %d\n", __func__, -EINVAL); goto free_m; } /* Convert 1st entry to int */ ret = kstrtoint (token, 10, &temp); if (ret) { dev_info(device, "%s: error parsing args %d\n", __func__, ret); goto free_m; } tl = int_to_short(temp); /* Split string using space char */ token = strsep(&p_args, " "); if (!token) { dev_info(device, "%s: error parsing args %d\n", __func__, -EINVAL); goto free_m; } /* Convert 2nd entry to int */ ret = kstrtoint (token, 10, &temp); if (ret) { dev_info(device, "%s: error parsing args %d\n", __func__, ret); goto free_m; } /* Prepare to cast to short by eliminating out of range values */ th = int_to_short(temp); /* Reorder if required th and tl */ if (tl > th) swap(tl, th); /* * Read the scratchpad to change only the required bits * (th : byte 2 - tl: byte 3) */ ret = read_scratchpad(sl, &info); if (!ret) { new_config_register[0] = th; /* Byte 2 */ new_config_register[1] = tl; /* Byte 3 */ new_config_register[2] = info.rom[4];/* Byte 4 */ } else { dev_info(device, "%s: error reading from the slave device %d\n", __func__, ret); goto free_m; } /* Write data in the device RAM */ if (!SLAVE_SPECIFIC_FUNC(sl)) { dev_info(device, "%s: Device not supported by the driver %d\n", __func__, -ENODEV); goto free_m; } ret = SLAVE_SPECIFIC_FUNC(sl)->write_data(sl, new_config_register); if (ret) dev_info(device, "%s: error writing to the slave device %d\n", __func__, ret); free_m: /* free allocated memory */ kfree(orig); return size; } static ssize_t therm_bulk_read_store(struct device *device, struct device_attribute *attr, const char *buf, size_t size) { struct w1_master *dev_master = dev_to_w1_master(device); int ret = -EINVAL; /* Invalid argument */ if (size == sizeof(BULK_TRIGGER_CMD)) if (!strncmp(buf, BULK_TRIGGER_CMD, sizeof(BULK_TRIGGER_CMD)-1)) ret = trigger_bulk_read(dev_master); if (ret) dev_info(device, "%s: unable to trigger a bulk read on the bus. err=%d\n", __func__, ret); return size; } static ssize_t therm_bulk_read_show(struct device *device, struct device_attribute *attr, char *buf) { struct w1_master *dev_master = dev_to_w1_master(device); struct w1_slave *sl = NULL; int ret = 0; list_for_each_entry(sl, &dev_master->slist, w1_slave_entry) { if (sl->family_data) { if (bulk_read_support(sl)) { if (SLAVE_CONVERT_TRIGGERED(sl) == -1) { ret = -1; goto show_result; } if (SLAVE_CONVERT_TRIGGERED(sl) == 1) /* continue to check other slaves */ ret = 1; } } } show_result: return sprintf(buf, "%d\n", ret); } static ssize_t conv_time_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 is not supported by the driver\n", __func__); return 0; /* No device family */ } return sprintf(buf, "%d\n", conversion_time(sl)); } static ssize_t conv_time_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); if (kstrtoint(buf, 10, &val)) /* converting user entry to int */ return -EINVAL; if (check_family_data(sl)) return -ENODEV; if (val != CONV_TIME_MEASURE) { if (val >= CONV_TIME_DEFAULT) SLAVE_CONV_TIME_OVERRIDE(sl) = val; else return -EINVAL; } else { int conv_time; ret = conv_time_measure(sl, &conv_time); if (ret) return -EIO; SLAVE_CONV_TIME_OVERRIDE(sl) = conv_time; } return size; } static ssize_t features_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 */ } return sprintf(buf, "%u\n", SLAVE_FEATURES(sl)); } static ssize_t features_store(struct device *device, struct device_attribute *attr, const char *buf, size_t size) { int val, ret = 0; bool strong_pullup; struct w1_slave *sl = dev_to_w1_slave(device); ret = kstrtouint(buf, 10, &val); /* converting user entry to int */ if (ret) return -EINVAL; /* invalid number */ if ((!sl->family_data) || (!SLAVE_SPECIFIC_FUNC(sl))) { dev_info(device, "%s: Device not supported by the driver\n", __func__); return -ENODEV; } if ((val & W1_THERM_FEATURES_MASK) != val) return -EINVAL; SLAVE_FEATURES(sl) = val; strong_pullup = (w1_strong_pullup == 2 || (!SLAVE_POWERMODE(sl) && w1_strong_pullup)); if (strong_pullup && SLAVE_FEATURES(sl) & W1_THERM_POLL_COMPLETION) { dev_warn(&sl->dev, "%s: W1_THERM_POLL_COMPLETION disabled in parasite power mode.\n", __func__); SLAVE_FEATURES(sl) &= ~W1_THERM_POLL_COMPLETION; } 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; int ret; switch (attr) { case hwmon_temp_input: ret = convert_t(sl, &info); if (ret) return ret; if (!info.verdict) { ret = -EIO; return ret; } *val = temperature_from_RAM(sl, info.rom); 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 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); 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; if (w1_reset_bus(sl->master)) goto error; /* Put the device into chain DONE state */ w1_write_8(sl->master, W1_MATCH_ROM); w1_write_block(sl->master, (u8 *)&rn, 8); 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); /* 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));