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-rw-r--r--drivers/hwmon/lm81.c148
1 files changed, 148 insertions, 0 deletions
diff --git a/drivers/hwmon/lm81.c b/drivers/hwmon/lm81.c
new file mode 100644
index 0000000000..03bc53d58c
--- /dev/null
+++ b/drivers/hwmon/lm81.c
@@ -0,0 +1,148 @@
+/*
+ * (C) Copyright 2006
+ * Heiko Schocher, DENX Software Enginnering <hs@denx.de>
+ *
+ * based on dtt/lm75.c which is ...
+ *
+ * (C) Copyright 2001
+ * Bill Hunter, Wave 7 Optics, williamhunter@mediaone.net
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+/*
+ * On Semiconductor's LM81 Temperature Sensor
+ */
+
+#include <common.h>
+
+#ifdef CONFIG_DTT_LM81
+#if !defined(CFG_EEPROM_PAGE_WRITE_ENABLE) || \
+ (CFG_EEPROM_PAGE_WRITE_BITS < 1)
+# error "CFG_EEPROM_PAGE_WRITE_ENABLE must be defined and CFG_EEPROM_PAGE_WRITE_BITS must be greater than 1 to use CONFIG_DTT_LM81"
+#endif
+
+#include <i2c.h>
+#include <dtt.h>
+
+/*
+ * Device code
+ */
+#define DTT_I2C_DEV_CODE 0x2c /* ON Semi's LM81 device */
+
+int dtt_read(int sensor, int reg)
+{
+ int dlen = 1;
+ uchar data[2];
+
+ /*
+ * Calculate sensor address and register.
+ */
+ sensor = DTT_I2C_DEV_CODE + (sensor & 0x03); /* calculate address of lm81 */
+
+ /*
+ * Now try to read the register.
+ */
+ if (i2c_read(sensor, reg, 1, data, dlen) != 0)
+ return -1;
+
+ return (int)data[0];
+} /* dtt_read() */
+
+
+int dtt_write(int sensor, int reg, int val)
+{
+ uchar data;
+
+ /*
+ * Calculate sensor address and register.
+ */
+ sensor = DTT_I2C_DEV_CODE + (sensor & 0x03); /* calculate address of lm81 */
+
+ data = (char)(val & 0xff);
+
+ /*
+ * Write value to register.
+ */
+ if (i2c_write(sensor, reg, 1, &data, 1) != 0)
+ return 1;
+
+ return 0;
+} /* dtt_write() */
+
+#define DTT_MANU 0x3e
+#define DTT_REV 0x3f
+#define DTT_CONFIG 0x40
+#define DTT_ADR 0x48
+
+static int _dtt_init(int sensor)
+{
+ int man;
+ int adr;
+ int rev;
+
+ if (dtt_write (sensor, DTT_CONFIG, 0x01) < 0)
+ return 1;
+ /* The LM81 needs 400ms to get the correct values ... */
+ udelay (400000);
+ man = dtt_read (sensor, DTT_MANU);
+ if (man != 0x01)
+ return 1;
+ adr = dtt_read (sensor, DTT_ADR);
+ if (adr < 0)
+ return 1;
+ rev = dtt_read (sensor, DTT_REV);
+ if (adr < 0)
+ return 1;
+
+ printf ("DTT: Found LM81@%x Rev: %d\n", adr, rev);
+ return 0;
+} /* _dtt_init() */
+
+
+int dtt_init (void)
+{
+ int i;
+ unsigned char sensors[] = CONFIG_DTT_SENSORS;
+ const char *const header = "DTT: ";
+
+ for (i = 0; i < sizeof(sensors); i++) {
+ if (_dtt_init(sensors[i]) != 0)
+ printf("%s%d FAILED INIT\n", header, i+1);
+ else
+ printf("%s%d is %i C\n", header, i+1,
+ dtt_get_temp(sensors[i]));
+ }
+
+ return (0);
+} /* dtt_init() */
+
+#define TEMP_FROM_REG(temp) \
+ ((temp)<256?((((temp)&0x1fe) >> 1) * 10) + ((temp) & 1) * 5: \
+ ((((temp)&0x1fe) >> 1) -255) * 10 - ((temp) & 1) * 5) \
+
+int dtt_get_temp(int sensor)
+{
+ int val = dtt_read (sensor, DTT_READ_TEMP);
+ int tmpcnf = dtt_read (sensor, DTT_CONFIG_TEMP);
+
+ return (TEMP_FROM_REG((val << 1) + ((tmpcnf & 0x80) >> 7))) / 10;
+} /* dtt_get_temp() */
+
+#endif /* CONFIG_DTT_LM81 */
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