#define W1_THERM_DS1825 0x3B
#define W1_THERM_DS28EA00 0x42
-/* Allow the strong pullup to be disabled, but default to enabled.
+/*
+ * 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.
static int w1_strong_pullup = 1;
module_param_named(strong_pullup, w1_strong_pullup, int, 0);
+/* Helpers Macros */
+
+/* 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
+ * @precision: pointer to the device precision function
+ * @eeprom: pointer to eeprom function
+ */
+struct w1_therm_family_converter {
+ u8 broken;
+ u16 reserved;
+ struct w1_family *f;
+ int (*convert)(u8 rom[9]);
+ int (*precision)(struct device *device, int val);
+ int (*eeprom)(struct device *device);
+};
+
+/**
+ * struct w1_therm_family_data - device data
+ * @rom: ROM device id (64bit Lasered ROM code + 1 CRC byte)
+ * @refcnt: ref count
+ */
struct w1_therm_family_data {
uint8_t rom[9];
atomic_t refcnt;
};
+/**
+ * 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;
};
-/* return the address of the refcnt in the family data */
-#define THERM_REFCNT(family_data) \
- (&((struct w1_therm_family_data *)family_data)->refcnt)
-
-static int w1_therm_add_slave(struct w1_slave *sl)
-{
- 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);
- return 0;
-}
-
-static void w1_therm_remove_slave(struct w1_slave *sl)
-{
- int refcnt = atomic_sub_return(1, THERM_REFCNT(sl->family_data));
-
- while (refcnt) {
- msleep(1000);
- refcnt = atomic_read(THERM_REFCNT(sl->family_data));
- }
- kfree(sl->family_data);
- sl->family_data = NULL;
-}
+/* Sysfs interface declaration */
static ssize_t w1_slave_show(struct device *device,
struct device_attribute *attr, char *buf);
static ssize_t w1_seq_show(struct device *device,
struct device_attribute *attr, char *buf);
+/* Attributes declarations */
+
static DEVICE_ATTR_RW(w1_slave);
static DEVICE_ATTR_RO(w1_seq);
+/* 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,
NULL,
NULL,
};
+/* Attribute groups */
+
ATTRIBUTE_GROUPS(w1_therm);
ATTRIBUTE_GROUPS(w1_ds28ea00);
#define W1_CHIPINFO NULL
#endif
+/* Family operations */
+
static struct w1_family_ops w1_therm_fops = {
.add_slave = w1_therm_add_slave,
.remove_slave = w1_therm_remove_slave,
.chip_info = W1_CHIPINFO,
};
+/* Family binding operations struct */
+
static struct w1_family w1_therm_family_DS18S20 = {
.fid = W1_THERM_DS18S20,
.fops = &w1_therm_fops,
.fops = &w1_therm_fops,
};
-struct w1_therm_family_converter {
- u8 broken;
- u16 reserved;
- struct w1_family *f;
- int (*convert)(u8 rom[9]);
- int (*precision)(struct device *device, int val);
- int (*eeprom)(struct device *device);
-};
+/* Device dependent func */
/* write configuration to eeprom */
static inline int w1_therm_eeprom(struct device *device);
-/* Set precision for conversion */
-static inline int w1_DS18B20_precision(struct device *device, int val);
-static inline int w1_DS18S20_precision(struct device *device, int val);
-
-/* The return value is millidegrees Centigrade. */
-static inline int w1_DS18B20_convert_temp(u8 rom[9]);
-static inline int w1_DS18S20_convert_temp(u8 rom[9]);
-
-static struct w1_therm_family_converter w1_therm_families[] = {
- {
- .f = &w1_therm_family_DS18S20,
- .convert = w1_DS18S20_convert_temp,
- .precision = w1_DS18S20_precision,
- .eeprom = w1_therm_eeprom
- },
- {
- .f = &w1_therm_family_DS1822,
- .convert = w1_DS18B20_convert_temp,
- .precision = w1_DS18S20_precision,
- .eeprom = w1_therm_eeprom
- },
- {
- .f = &w1_therm_family_DS18B20,
- .convert = w1_DS18B20_convert_temp,
- .precision = w1_DS18B20_precision,
- .eeprom = w1_therm_eeprom
- },
- {
- .f = &w1_therm_family_DS28EA00,
- .convert = w1_DS18B20_convert_temp,
- .precision = w1_DS18S20_precision,
- .eeprom = w1_therm_eeprom
- },
- {
- .f = &w1_therm_family_DS1825,
- .convert = w1_DS18B20_convert_temp,
- .precision = w1_DS18S20_precision,
- .eeprom = w1_therm_eeprom
- }
-};
-
-static inline int w1_therm_eeprom(struct device *device)
-{
- struct w1_slave *sl = dev_to_w1_slave(device);
- struct w1_master *dev = sl->master;
- u8 rom[9], external_power;
- int ret, max_trying = 10;
- u8 *family_data = sl->family_data;
-
- if (!sl->family_data) {
- ret = -ENODEV;
- goto error;
- }
-
- /* prevent the slave from going away in sleep */
- atomic_inc(THERM_REFCNT(family_data));
-
- ret = mutex_lock_interruptible(&dev->bus_mutex);
- if (ret != 0)
- goto dec_refcnt;
-
- memset(rom, 0, sizeof(rom));
-
- while (max_trying--) {
- if (!w1_reset_select_slave(sl)) {
- unsigned int tm = 10;
- unsigned long sleep_rem;
-
- /* check if in parasite mode */
- w1_write_8(dev, W1_READ_PSUPPLY);
- external_power = w1_read_8(dev);
-
- if (w1_reset_select_slave(sl))
- continue;
-
- /* 10ms strong pullup/delay after the copy command */
- if (w1_strong_pullup == 2 ||
- (!external_power && w1_strong_pullup))
- w1_next_pullup(dev, tm);
-
- w1_write_8(dev, W1_COPY_SCRATCHPAD);
-
- if (external_power) {
- mutex_unlock(&dev->bus_mutex);
-
- sleep_rem = msleep_interruptible(tm);
- if (sleep_rem != 0) {
- ret = -EINTR;
- goto dec_refcnt;
- }
-
- ret = mutex_lock_interruptible(&dev->bus_mutex);
- if (ret != 0)
- goto dec_refcnt;
- } else if (!w1_strong_pullup) {
- sleep_rem = msleep_interruptible(tm);
- if (sleep_rem != 0) {
- ret = -EINTR;
- goto mt_unlock;
- }
- }
-
- break;
- }
- }
-
-mt_unlock:
- mutex_unlock(&dev->bus_mutex);
-dec_refcnt:
- atomic_dec(THERM_REFCNT(family_data));
-error:
- return ret;
-}
-
/* DS18S20 does not feature configuration register */
static inline int w1_DS18S20_precision(struct device *device, int val)
{
return 0;
}
+/* Set precision for conversion */
static inline int w1_DS18B20_precision(struct device *device, int val)
{
struct w1_slave *sl = dev_to_w1_slave(device);
return ret;
}
+/**
+ * w1_DS18B20_convert_temp() - temperature computation for DS18B20
+ * @rom: data read from device RAM (8 data bytes + 1 CRC byte)
+ *
+ * Can be called for any DS18B20 compliant device.
+ *
+ * Return: value in millidegrees Celsius.
+ */
static inline int w1_DS18B20_convert_temp(u8 rom[9])
{
s16 t = le16_to_cpup((__le16 *)rom);
return t*1000/16;
}
+/**
+ * w1_DS18S20_convert_temp() - temperature computation for DS18S20
+ * @rom: data read from device RAM (8 data bytes + 1 CRC byte)
+ *
+ * Can be called for any DS18S20 compliant device.
+ *
+ * Return: value in millidegrees Celsius.
+ */
static inline int w1_DS18S20_convert_temp(u8 rom[9])
{
int t, h;
return t;
}
+/* Device capability description */
+
+static struct w1_therm_family_converter w1_therm_families[] = {
+ {
+ .f = &w1_therm_family_DS18S20,
+ .convert = w1_DS18S20_convert_temp,
+ .precision = w1_DS18S20_precision,
+ .eeprom = w1_therm_eeprom
+ },
+ {
+ .f = &w1_therm_family_DS1822,
+ .convert = w1_DS18B20_convert_temp,
+ .precision = w1_DS18S20_precision,
+ .eeprom = w1_therm_eeprom
+ },
+ {
+ .f = &w1_therm_family_DS18B20,
+ .convert = w1_DS18B20_convert_temp,
+ .precision = w1_DS18B20_precision,
+ .eeprom = w1_therm_eeprom
+ },
+ {
+ .f = &w1_therm_family_DS28EA00,
+ .convert = w1_DS18B20_convert_temp,
+ .precision = w1_DS18S20_precision,
+ .eeprom = w1_therm_eeprom
+ },
+ {
+ .f = &w1_therm_family_DS1825,
+ .convert = w1_DS18B20_convert_temp,
+ .precision = w1_DS18S20_precision,
+ .eeprom = w1_therm_eeprom
+ }
+};
+
+/* Helpers Functions */
+
+/**
+ * w1_convert_temp() - temperature conversion binding function
+ * @rom: data read from device RAM (8 data bytes + 1 CRC byte)
+ * @fid: device family id
+ *
+ * The function call the temperature computation function according to
+ * device family.
+ *
+ * Return: value in millidegrees Celsius.
+ */
static inline int w1_convert_temp(u8 rom[9], u8 fid)
{
int i;
return 0;
}
-static ssize_t w1_slave_store(struct device *device,
- struct device_attribute *attr, const char *buf,
- size_t size)
+/* Interface Functions */
+
+static int w1_therm_add_slave(struct w1_slave *sl)
{
- int val, ret;
- struct w1_slave *sl = dev_to_w1_slave(device);
- int i;
+ 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);
+ return 0;
+}
- ret = kstrtoint(buf, 0, &val);
- if (ret)
- return ret;
+static void w1_therm_remove_slave(struct w1_slave *sl)
+{
+ int refcnt = atomic_sub_return(1, THERM_REFCNT(sl->family_data));
- for (i = 0; i < ARRAY_SIZE(w1_therm_families); ++i) {
- if (w1_therm_families[i].f->fid == sl->family->fid) {
- /* zero value indicates to write current configuration to eeprom */
- if (val == 0)
- ret = w1_therm_families[i].eeprom(device);
- else
- ret = w1_therm_families[i].precision(device, val);
- break;
- }
+ while (refcnt) {
+ msleep(1000);
+ refcnt = atomic_read(THERM_REFCNT(sl->family_data));
}
- return ret ? : size;
+ kfree(sl->family_data);
+ sl->family_data = NULL;
}
+/* Hardware Functions */
+
static ssize_t read_therm(struct device *device,
struct w1_slave *sl, struct therm_info *info)
{
return ret;
}
+static inline int w1_therm_eeprom(struct device *device)
+{
+ struct w1_slave *sl = dev_to_w1_slave(device);
+ struct w1_master *dev = sl->master;
+ u8 rom[9], external_power;
+ int ret, max_trying = 10;
+ u8 *family_data = sl->family_data;
+
+ if (!sl->family_data) {
+ ret = -ENODEV;
+ goto error;
+ }
+
+ /* prevent the slave from going away in sleep */
+ atomic_inc(THERM_REFCNT(family_data));
+
+ ret = mutex_lock_interruptible(&dev->bus_mutex);
+ if (ret != 0)
+ goto dec_refcnt;
+
+ memset(rom, 0, sizeof(rom));
+
+ while (max_trying--) {
+ if (!w1_reset_select_slave(sl)) {
+ unsigned int tm = 10;
+ unsigned long sleep_rem;
+
+ /* check if in parasite mode */
+ w1_write_8(dev, W1_READ_PSUPPLY);
+ external_power = w1_read_8(dev);
+
+ if (w1_reset_select_slave(sl))
+ continue;
+
+ /* 10ms strong pullup/delay after the copy command */
+ if (w1_strong_pullup == 2 ||
+ (!external_power && w1_strong_pullup))
+ w1_next_pullup(dev, tm);
+
+ w1_write_8(dev, W1_COPY_SCRATCHPAD);
+
+ if (external_power) {
+ mutex_unlock(&dev->bus_mutex);
+
+ sleep_rem = msleep_interruptible(tm);
+ if (sleep_rem != 0) {
+ ret = -EINTR;
+ goto dec_refcnt;
+ }
+
+ ret = mutex_lock_interruptible(&dev->bus_mutex);
+ if (ret != 0)
+ goto dec_refcnt;
+ } else if (!w1_strong_pullup) {
+ sleep_rem = msleep_interruptible(tm);
+ if (sleep_rem != 0) {
+ ret = -EINTR;
+ goto mt_unlock;
+ }
+ }
+
+ break;
+ }
+ }
+
+mt_unlock:
+ mutex_unlock(&dev->bus_mutex);
+dec_refcnt:
+ atomic_dec(THERM_REFCNT(family_data));
+error:
+ return ret;
+}
+
+/* Sysfs Interface definition */
+
static ssize_t w1_slave_show(struct device *device,
struct device_attribute *attr, char *buf)
{
return ret;
}
+static ssize_t w1_slave_store(struct device *device,
+ struct device_attribute *attr, const char *buf,
+ size_t size)
+{
+ int val, ret;
+ struct w1_slave *sl = dev_to_w1_slave(device);
+ int i;
+
+ ret = kstrtoint(buf, 0, &val);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < ARRAY_SIZE(w1_therm_families); ++i) {
+ if (w1_therm_families[i].f->fid == sl->family->fid) {
+ /* zero value indicates to write current configuration to eeprom */
+ if (val == 0)
+ ret = w1_therm_families[i].eeprom(device);
+ else
+ ret = w1_therm_families[i].precision(device,
+ val);
+ break;
+ }
+ }
+ return ret ? : size;
+}
+
#if IS_REACHABLE(CONFIG_HWMON)
static int w1_read_temp(struct device *device, u32 attr, int channel,
long *val)
if (ack != W1_42_SUCCESS_CONFIRM_BYTE)
goto error;
- /* In case the bus fails to send 0xFF, limit*/
+ /* In case the bus fails to send 0xFF, limit */
for (i = 0; i <= 64; i++) {
if (w1_reset_bus(sl->master))
goto error;
projects / linux.git / commitdiff