diff options
Diffstat (limited to 'drivers/hwmon/ds1621.c')
| -rw-r--r-- | drivers/hwmon/ds1621.c | 213 | 
1 files changed, 98 insertions, 115 deletions
| diff --git a/drivers/hwmon/ds1621.c b/drivers/hwmon/ds1621.c index ec1893e1d..60bf50203 100644 --- a/drivers/hwmon/ds1621.c +++ b/drivers/hwmon/ds1621.c @@ -32,7 +32,7 @@  /*   * Device code   */ -#define DTT_I2C_DEV_CODE 0x48			/* Dallas Semi's DS1621 */ +#define DTT_I2C_DEV_CODE 	0x48	/* Dallas Semi's DS1621 */  #define DTT_READ_TEMP		0xAA  #define DTT_READ_COUNTER	0xA8  #define DTT_READ_SLOPE		0xA9 @@ -47,8 +47,8 @@   */  #define DTT_CONFIG_1SHOT	0x01  #define DTT_CONFIG_POLARITY	0x02 -#define DTT_CONFIG_R0		0x04 /* ds1631 only */ -#define DTT_CONFIG_R1		0x08 /* ds1631 only */ +#define DTT_CONFIG_R0		0x04	/* ds1631 only */ +#define DTT_CONFIG_R1		0x08	/* ds1631 only */  #define DTT_CONFIG_NVB		0x10  #define DTT_CONFIG_TLF		0x20  #define DTT_CONFIG_THF		0x40 @@ -57,149 +57,132 @@  int dtt_read(int sensor, int reg)  { -    int dlen; -    uchar data[2]; +	int dlen; +	uchar data[2]; -    /* -     * Calculate sensor address and command. -     * -     */ -    sensor = DTT_I2C_DEV_CODE + (sensor & 0x07); /* Calculate addr of ds1621*/ +	/* Calculate sensor address and command */ +	sensor = DTT_I2C_DEV_CODE + (sensor & 0x07); /* Calculate addr of ds1621*/ -    /* -     * Prepare to handle 2 byte result. -     */ -    if ((reg == DTT_READ_TEMP) || -	(reg == DTT_TEMP_HIGH) || (reg == DTT_TEMP_LOW)) -	dlen = 2; -    else -	dlen = 1; +	/* Prepare to handle 2 byte result */ +	switch(reg) { +	case DTT_READ_TEMP: +	case DTT_TEMP_HIGH: +	case DTT_TEMP_LOW: +		dlen = 2; +		break; +	default: +		dlen = 1; +	} -    /* -     * Now try to read the register. -     */ -    if (i2c_read(sensor, reg, 1, data, dlen) != 0) -	return 1; +	/* Now try to read the register */ +	if (i2c_read(sensor, reg, 1, data, dlen) != 0) +		return 1; -    /* -     * Handle 2 byte result. -     */ -    if (dlen == 2) -	return ((int)((short)data[1] + (((short)data[0]) << 8))); +	/* Handle 2 byte result */ +	if (dlen == 2) +		return ((int)((short)data[1] + (((short)data[0]) << 8))); -    return (int)data[0]; -} /* dtt_read() */ +	return (int)data[0]; +}  int dtt_write(int sensor, int reg, int val)  { -    int dlen; -    uchar data[2]; +	int dlen; +	uchar data[2]; -    /* -     * Calculate sensor address and register. -     * -     */ -    sensor = DTT_I2C_DEV_CODE + (sensor & 0x07); +	/* Calculate sensor address and register */ +	sensor = DTT_I2C_DEV_CODE + (sensor & 0x07); -    /* -     * Handle various data sizes. -     */ -    if ((reg == DTT_READ_TEMP) || -	(reg == DTT_TEMP_HIGH) || (reg == DTT_TEMP_LOW)) { -	dlen = 2; -	data[0] = (char)((val >> 8) & 0xff);	/* MSB first */ -	data[1] = (char)(val & 0xff); -    } -    else if ((reg == DTT_WRITE_START_CONV) || (reg == DTT_WRITE_STOP_CONV)) { -	dlen = 0; -	data[0] = (char)0; -	data[1] = (char)0; -    } -    else { -	dlen = 1; -	data[0] = (char)(val & 0xff); -    } +	/* Handle various data sizes. */ +	switch(reg) { +	case DTT_READ_TEMP: +	case DTT_TEMP_HIGH: +	case DTT_TEMP_LOW: +		dlen = 2; +		data[0] = (char)((val >> 8) & 0xff);	/* MSB first */ +		data[1] = (char)(val & 0xff); +		break; +	case DTT_WRITE_START_CONV: +	case DTT_WRITE_STOP_CONV: +		dlen = 0; +		data[0] = (char)0; +		data[1] = (char)0; +		break; +	default: +		dlen = 1; +		data[0] = (char)(val & 0xff); +	} -    /* -     * Write value to device. -     */ -    if (i2c_write(sensor, reg, 1, data, dlen) != 0) -	return 1; +	/* Write value to device */ +	if (i2c_write(sensor, reg, 1, data, dlen) != 0) +		return 1; -    /* -     * Poll NV memory busy bit in case write was to register stored in EEPROM -     */ -    while(i2c_reg_read(sensor, DTT_CONFIG) & DTT_CONFIG_NVB) -        ; +	/* Poll NV memory busy bit in case write was to register stored in EEPROM */ +	while(i2c_reg_read(sensor, DTT_CONFIG) & DTT_CONFIG_NVB) +		; -    return 0; -} /* dtt_write() */ +	return 0; +}  static int _dtt_init(int sensor)  { -    int val; +	int val; -    /* -     * Setup High Temp. -     */ -    val = ((CONFIG_SYS_DTT_MAX_TEMP * 2) << 7) & 0xff80; -    if (dtt_write(sensor, DTT_TEMP_HIGH, val) != 0) -	return 1; +	/* Setup High Temp */ +	val = ((CONFIG_SYS_DTT_MAX_TEMP * 2) << 7) & 0xff80; +	if (dtt_write(sensor, DTT_TEMP_HIGH, val) != 0) +		return 1; -    /* -     * Setup Low Temp - hysteresis. -     */ -    val = (((CONFIG_SYS_DTT_MAX_TEMP - CONFIG_SYS_DTT_HYSTERESIS) * 2) << 7) & 0xff80; -    if (dtt_write(sensor, DTT_TEMP_LOW, val) != 0) -	return 1; +	/* Setup Low Temp - hysteresis */ +	val = (((CONFIG_SYS_DTT_MAX_TEMP - CONFIG_SYS_DTT_HYSTERESIS) * 2) << 7) & 0xff80; +	if (dtt_write(sensor, DTT_TEMP_LOW, val) != 0) +		return 1; -    /* -     * Setup configuraton register -     * -     * Clear THF & TLF, Reserved = 1, Polarity = Active Low, One Shot = YES -     * -     * We run in polled mode, since there isn't any way to know if this -     * lousy device is ready to provide temperature readings on power up. -     */ -    val = 0x9; -    if (dtt_write(sensor, DTT_CONFIG, val) != 0) -	return 1; +	/* +	 * Setup configuraton register +	 * +	 * Clear THF & TLF, Reserved = 1, Polarity = Active Low, One Shot = YES +	 * +	 * We run in polled mode, since there isn't any way to know if this +	 * lousy device is ready to provide temperature readings on power up. +	 */ +	val = 0x9; +	if (dtt_write(sensor, DTT_CONFIG, val) != 0) +		return 1; -    return 0; -} /* _dtt_init() */ +	return 0; +}  int dtt_init (void)  { -    int i; -    unsigned char sensors[] = CONFIG_DTT_SENSORS; +	int i; +	unsigned char sensors[] = CONFIG_DTT_SENSORS; -    for (i = 0; i < sizeof(sensors); i++) { -	if (_dtt_init(sensors[i]) != 0) -	    printf("DTT%d:  FAILED\n", i+1); -	else -	    printf("DTT%d:  %i C\n", i+1, dtt_get_temp(sensors[i])); -    } +	for (i = 0; i < sizeof(sensors); i++) { +		if (_dtt_init(sensors[i]) != 0) +			printf("DTT%d:  FAILED\n", i + 1); +		else +			printf("DTT%d:  %i C\n", i + 1, dtt_get_temp(sensors[i])); +	} -    return (0); -} /* dtt_init() */ +	return (0); +}  int dtt_get_temp(int sensor)  { -    int i; +	int i; -    /* -     * Start a conversion, may take up to 1 second. -     */ -    dtt_write(sensor, DTT_WRITE_START_CONV, 0); -    for (i = 0; i <= 10; i++) { -	udelay(100000); -	if (dtt_read(sensor, DTT_CONFIG) & DTT_CONFIG_DONE) -	    break; -    } +	/* Start a conversion, may take up to 1 second. */ +	dtt_write(sensor, DTT_WRITE_START_CONV, 0); +	for (i = 0; i <= 10; i++) { +		udelay(100000); +		if (dtt_read(sensor, DTT_CONFIG) & DTT_CONFIG_DONE) +			break; +	} -    return (dtt_read(sensor, DTT_READ_TEMP) / 256); -} /* dtt_get_temp() */ +	return (dtt_read(sensor, DTT_READ_TEMP) / 256); +} |