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| author | Peter Tyser <ptyser@xes-inc.com> | 2010-09-29 13:46:17 -0500 |
|---|---|---|
| committer | Wolfgang Denk <wd@denx.de> | 2010-10-06 23:01:19 +0200 |
| commit | c3e5fa0b53c0a83c87298e486ae7ec663d44566f (patch) | |
| tree | 0350100f710d73547119a3ccc14800387a73eb63 /drivers/hwmon | |
| parent | fc5fc76bdad14425e3743e1494c9e444570df1be (diff) | |
| download | blackbird-obmc-uboot-c3e5fa0b53c0a83c87298e486ae7ec663d44566f.tar.gz blackbird-obmc-uboot-c3e5fa0b53c0a83c87298e486ae7ec663d44566f.zip | |
ds1621: Poll for register write completion
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>
Diffstat (limited to 'drivers/hwmon')
| -rw-r--r-- | 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 d15a082df5..ec1893e1d3 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; } |
