diff options
Diffstat (limited to 'drivers/hwmon/ds1621.c')
| -rw-r--r-- | drivers/hwmon/ds1621.c | 245 |
1 files changed, 114 insertions, 131 deletions
diff --git a/drivers/hwmon/ds1621.c b/drivers/hwmon/ds1621.c index ec1893e..60bf502 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]; - - /* - * 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; - - /* - * 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))); - - return (int)data[0]; -} /* dtt_read() */ + int dlen; + uchar data[2]; + + /* Calculate sensor address and command */ + sensor = DTT_I2C_DEV_CODE + (sensor & 0x07); /* Calculate addr of ds1621*/ + + /* 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; + + /* Handle 2 byte result */ + if (dlen == 2) + return ((int)((short)data[1] + (((short)data[0]) << 8))); + + return (int)data[0]; +} int dtt_write(int sensor, int reg, int val) { - int dlen; - uchar data[2]; - - /* - * 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); - } - - /* - * 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) - ; - - return 0; -} /* dtt_write() */ + int dlen; + uchar data[2]; + + /* Calculate sensor address and register */ + sensor = DTT_I2C_DEV_CODE + (sensor & 0x07); + + /* 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; + + /* 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; +} static int _dtt_init(int sensor) { - 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 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; - - return 0; -} /* _dtt_init() */ + 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 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; + + 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; - - /* - * 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() */ + 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; + } + + return (dtt_read(sensor, DTT_READ_TEMP) / 256); +} |