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path: root/drivers/hwmon/ds1621.c
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-rw-r--r--drivers/hwmon/ds1621.c253
1 files changed, 126 insertions, 127 deletions
diff --git a/drivers/hwmon/ds1621.c b/drivers/hwmon/ds1621.c
index d15a082..5a2ea62 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>
@@ -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
@@ -42,148 +42,147 @@
#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;
- 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 (short)((data[0] << 8) | data[1]);
+
+ 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;
-
- 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;
- udelay(50000); /* Max 50ms */
-
- /*
- * 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;
- udelay(50000); /* Max 50ms */
-
- /*
- * 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;
- udelay(50000); /* Max 50ms */
-
- 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) & 0x80)
- 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);
+}
generated by cgit v1.1 at 2024-12-29 05:45:21 +0000