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Diffstat (limited to '')
| -rw-r--r-- | drivers/w1/slaves/w1_therm.c | 2224 |
1 files changed, 2224 insertions, 0 deletions
diff --git a/drivers/w1/slaves/w1_therm.c b/drivers/w1/slaves/w1_therm.c new file mode 100644 index 000000000..99c58bd9d --- /dev/null +++ b/drivers/w1/slaves/w1_therm.c @@ -0,0 +1,2224 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * w1_therm.c + * + * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net> + */ + +#include <asm/types.h> + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/sched.h> +#include <linux/device.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/delay.h> +#include <linux/hwmon.h> +#include <linux/string.h> +#include <linux/jiffies.h> + +#include <linux/w1.h> + +#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 commmand 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 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 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 = t_cur > t_conv ? 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 <zbr@ioremap.net>"); +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)); |