drivers/hwmon/lm85.c

Source file repositories/reference/linux-study-clean/drivers/hwmon/lm85.c

File Facts

System
Linux kernel
Corpus path
drivers/hwmon/lm85.c
Extension
.c
Size
50249 bytes
Lines
1709
Domain
Driver Families
Bucket
drivers/hwmon
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct lm85_zone {
	s8 limit;	/* Low temp limit */
	u8 hyst;	/* Low limit hysteresis. (0-15) */
	u8 range;	/* Temp range, encoded */
	s8 critical;	/* "All fans ON" temp limit */
	u8 max_desired; /*
			 * Actual "max" temperature specified.  Preserved
			 * to prevent "drift" as other autofan control
			 * values change.
			 */
};

struct lm85_autofan {
	u8 config;	/* Register value */
	u8 min_pwm;	/* Minimum PWM value, encoded */
	u8 min_off;	/* Min PWM or OFF below "limit", flag */
};

/*
 * For each registered chip, we need to keep some data in memory.
 * The structure is dynamically allocated.
 */
struct lm85_data {
	struct i2c_client *client;
	const struct attribute_group *groups[6];
	const int *freq_map;
	unsigned int freq_map_size;

	enum chips type;

	bool has_vid5;	/* true if VID5 is configured for ADT7463 or ADT7468 */

	struct mutex update_lock;
	bool valid;		/* true if following fields are valid */
	unsigned long last_reading;	/* In jiffies */
	unsigned long last_config;	/* In jiffies */

	u8 in[8];		/* Register value */
	u8 in_max[8];		/* Register value */
	u8 in_min[8];		/* Register value */
	s8 temp[3];		/* Register value */
	s8 temp_min[3];		/* Register value */
	s8 temp_max[3];		/* Register value */
	u16 fan[4];		/* Register value */
	u16 fan_min[4];		/* Register value */
	u8 pwm[3];		/* Register value */
	u8 pwm_freq[3];		/* Register encoding */
	u8 temp_ext[3];		/* Decoded values */
	u8 in_ext[8];		/* Decoded values */
	u8 vid;			/* Register value */
	u8 vrm;			/* VRM version */
	u32 alarms;		/* Register encoding, combined */
	u8 cfg5;		/* Config Register 5 on ADT7468 */
	struct lm85_autofan autofan[3];
	struct lm85_zone zone[3];
};

static int lm85_read_value(struct i2c_client *client, u8 reg)
{
	int res;

	/* What size location is it? */
	switch (reg) {
	case LM85_REG_FAN(0):  /* Read WORD data */
	case LM85_REG_FAN(1):
	case LM85_REG_FAN(2):
	case LM85_REG_FAN(3):
	case LM85_REG_FAN_MIN(0):
	case LM85_REG_FAN_MIN(1):
	case LM85_REG_FAN_MIN(2):
	case LM85_REG_FAN_MIN(3):
	case LM85_REG_ALARM1:	/* Read both bytes at once */
		res = i2c_smbus_read_byte_data(client, reg) & 0xff;
		res |= i2c_smbus_read_byte_data(client, reg + 1) << 8;
		break;
	default:	/* Read BYTE data */
		res = i2c_smbus_read_byte_data(client, reg);
		break;
	}

	return res;
}

static void lm85_write_value(struct i2c_client *client, u8 reg, int value)
{
	switch (reg) {
	case LM85_REG_FAN(0):  /* Write WORD data */
	case LM85_REG_FAN(1):
	case LM85_REG_FAN(2):
	case LM85_REG_FAN(3):

Annotation

Implementation Notes