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ds1621: Poll for register write completion

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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>
This commit is contained in:
Peter Tyser 2010-09-29 13:46:17 -05:00 committed by Wolfgang Denk
parent fc5fc76bda
commit c3e5fa0b53
1 changed files with 21 additions and 5 deletions
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26
drivers/hwmon/ds1621.c
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@ -22,7 +22,7 @@
*/ */
/* /*
* Dallas Semiconductor's DS1621 Digital Thermometer and Thermostat. * Dallas Semiconductor's DS1621/1631 Digital Thermometer and Thermostat.
*/ */
#include <common.h> #include <common.h>
@ -42,6 +42,19 @@
#define DTT_TEMP_LOW 0xA2 #define DTT_TEMP_LOW 0xA2
#define DTT_CONFIG 0xAC #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 dtt_read(int sensor, int reg)
{ {
int dlen; int dlen;
@ -114,6 +127,12 @@ int dtt_write(int sensor, int reg, int val)
if (i2c_write(sensor, reg, 1, data, dlen) != 0) if (i2c_write(sensor, reg, 1, data, dlen) != 0)
return 1; 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; return 0;
} /* dtt_write() */ } /* dtt_write() */
@ -128,7 +147,6 @@ static int _dtt_init(int sensor)
val = ((CONFIG_SYS_DTT_MAX_TEMP * 2) << 7) & 0xff80; val = ((CONFIG_SYS_DTT_MAX_TEMP * 2) << 7) & 0xff80;
if (dtt_write(sensor, DTT_TEMP_HIGH, val) != 0) if (dtt_write(sensor, DTT_TEMP_HIGH, val) != 0)
return 1; return 1;
udelay(50000); /* Max 50ms */
/* /*
* Setup Low Temp - hysteresis. * 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; val = (((CONFIG_SYS_DTT_MAX_TEMP - CONFIG_SYS_DTT_HYSTERESIS) * 2) << 7) & 0xff80;
if (dtt_write(sensor, DTT_TEMP_LOW, val) != 0) if (dtt_write(sensor, DTT_TEMP_LOW, val) != 0)
return 1; return 1;
udelay(50000); /* Max 50ms */
/* /*
* Setup configuraton register * Setup configuraton register
@ -149,7 +166,6 @@ static int _dtt_init(int sensor)
val = 0x9; val = 0x9;
if (dtt_write(sensor, DTT_CONFIG, val) != 0) if (dtt_write(sensor, DTT_CONFIG, val) != 0)
return 1; return 1;
udelay(50000); /* Max 50ms */
return 0; return 0;
} /* _dtt_init() */ } /* _dtt_init() */
@ -181,7 +197,7 @@ int dtt_get_temp(int sensor)
dtt_write(sensor, DTT_WRITE_START_CONV, 0); dtt_write(sensor, DTT_WRITE_START_CONV, 0);
for (i = 0; i <= 10; i++) { for (i = 0; i <= 10; i++) {
udelay(100000); udelay(100000);
if (dtt_read(sensor, DTT_CONFIG) & 0x80) if (dtt_read(sensor, DTT_CONFIG) & DTT_CONFIG_DONE)
break; break;
} }