Poll the ds1621 NV Memory Busy bit instead of waiting a static amount of time for register writes.
Also add config retister bit defines.
Signed-off-by: Peter Tyser ptyser@xes-inc.com --- drivers/hwmon/ds1621.c | 26 +++++++++++++++++++++----- 1 files changed, 21 insertions(+), 5 deletions(-)
diff --git a/drivers/hwmon/ds1621.c b/drivers/hwmon/ds1621.c index d15a082..ec1893e 100644 --- a/drivers/hwmon/ds1621.c +++ b/drivers/hwmon/ds1621.c @@ -22,7 +22,7 @@ */
/* - * Dallas Semiconductor's DS1621 Digital Thermometer and Thermostat. + * Dallas Semiconductor's DS1621/1631 Digital Thermometer and Thermostat. */
#include <common.h> @@ -42,6 +42,19 @@ #define DTT_TEMP_LOW 0xA2 #define DTT_CONFIG 0xAC
+/* + * Config register bits + */ +#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_NVB 0x10 +#define DTT_CONFIG_TLF 0x20 +#define DTT_CONFIG_THF 0x40 +#define DTT_CONFIG_DONE 0x80 + + int dtt_read(int sensor, int reg) { int dlen; @@ -114,6 +127,12 @@ int dtt_write(int sensor, int reg, int val) 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() */
@@ -128,7 +147,6 @@ static int _dtt_init(int sensor) val = ((CONFIG_SYS_DTT_MAX_TEMP * 2) << 7) & 0xff80; if (dtt_write(sensor, DTT_TEMP_HIGH, val) != 0) return 1; - udelay(50000); /* Max 50ms */
/* * Setup Low Temp - hysteresis. @@ -136,7 +154,6 @@ static int _dtt_init(int sensor) val = (((CONFIG_SYS_DTT_MAX_TEMP - CONFIG_SYS_DTT_HYSTERESIS) * 2) << 7) & 0xff80; if (dtt_write(sensor, DTT_TEMP_LOW, val) != 0) return 1; - udelay(50000); /* Max 50ms */
/* * Setup configuraton register @@ -149,7 +166,6 @@ static int _dtt_init(int sensor) val = 0x9; if (dtt_write(sensor, DTT_CONFIG, val) != 0) return 1; - udelay(50000); /* Max 50ms */
return 0; } /* _dtt_init() */ @@ -181,7 +197,7 @@ int dtt_get_temp(int sensor) dtt_write(sensor, DTT_WRITE_START_CONV, 0); for (i = 0; i <= 10; i++) { udelay(100000); - if (dtt_read(sensor, DTT_CONFIG) & 0x80) + if (dtt_read(sensor, DTT_CONFIG) & DTT_CONFIG_DONE) break; }