Add driver for National Semiconductor LM73 temperature sensor

This driver is based on the driver for the LM75.

---
 drivers/hwmon/Makefile |    1 +
 drivers/hwmon/lm73.c   |  181 ++++++++++++++++++++++++++++++++++++++++++++++++
 include/dtt.h          |   12 +++-
 3 files changed, 193 insertions(+), 1 deletions(-)
 create mode 100644 drivers/hwmon/lm73.c

index cebb2ba..32e3f44 100644
@@ -34,6 +34,7 @@ COBJS-y += adm1021.o
 COBJS-y += ds1621.o
 COBJS-y += ds1722.o
 COBJS-y += ds1775.o
+COBJS-y += lm73.o
 COBJS-y += lm75.o
 COBJS-y += lm81.o
 

new file mode 100644
index 0000000..f9ae012
@@ -0,0 +1,181 @@
+/*
+ * (C) Copyright 2007
+ * Larry Johnson, lrj at acm.org
+ *
+ * based on dtt/lm75.c which is ...
+ *
+ * (C) Copyright 2001
+ * Bill Hunter,  Wave 7 Optics, williamhunter at 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
+ */
+
+/*
+ * National Semiconductor LM73 Temperature Sensor
+ */
+
+#include <common.h>
+
+#ifdef CONFIG_DTT_LM73
+#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_LM73"
+#endif
+
+#include <i2c.h>
+#include <dtt.h>
+
+/*
+ * Device code
+ */
+#define DTT_I2C_DEV_CODE 0x48 /* National Semi's LM73 device */
+
+int dtt_read(int sensor, int reg)
+{
+ int dlen;
+ uchar data[2];
+
+ /*
+ * Validate 'reg' param and get register size.
+ */
+ switch (reg) {
+ case DTT_CONFIG:
+ case DTT_CONTROL:
+ dlen = 1;
+ break;
+ case DTT_READ_TEMP:
+ case DTT_TEMP_HIGH:
+ case DTT_TEMP_LOW:
+ case DTT_ID:
+ dlen = 2;
+ break;
+ default:
+ return -1;
+ }
+ /*
+ * Calculate sensor address and register.
+ */
+ sensor = DTT_I2C_DEV_CODE + (sensor & 0x07); /* calculate LM73 addr */
+ /*
+ * Now try to read the register.
+ */
+ if (i2c_read(sensor, reg, 1, data, dlen) != 0)
+ return -1;
+ /*
+ * Handle 2 byte result.
+ */
+ if (2 == dlen)
+ return ((int)((short)data[1] + (((short)data[0]) << 8)));
+
+ return (int)data[0];
+} /* dtt_read() */
+
+int dtt_write(int sensor, int reg, int val)
+{
+ int dlen;
+ uchar data[2];
+
+ /*
+ * Validate 'reg' param and handle register size
+ */
+ switch (reg) {
+ case DTT_CONFIG:
+ case DTT_CONTROL:
+ dlen = 1;
+ data[0] = (char)(val & 0xff);
+ break;
+ case DTT_TEMP_HIGH:
+ case DTT_TEMP_LOW:
+ dlen = 2;
+ data[0] = (char)((val >> 8) & 0xff); /* MSB first */
+ data[1] = (char)(val & 0xff);
+ break;
+ default:
+ return -1;
+ }
+ /*
+ * Calculate sensor address and register.
+ */
+ sensor = DTT_I2C_DEV_CODE + (sensor & 0x07); /* calculate LM73 addr */
+ /*
+ * Write value to register.
+ */
+ return i2c_write(sensor, reg, 1, data, dlen) != 0;
+} /* dtt_write() */
+
+static int _dtt_init(int sensor)
+{
+ int val;
+
+ /*
+ * Validate the Identification register
+ */
+ if (0x0190 != dtt_read(sensor, DTT_ID))
+ return 1;
+ /*
+ * Setup THIGH (upper-limit) and TLOW (lower-limit) registers
+ */
+ val = CFG_DTT_MAX_TEMP << 7;
+ if (dtt_write(sensor, DTT_TEMP_HIGH, val))
+ return 1;
+
+ val = CFG_DTT_MIN_TEMP << 7;
+ if (dtt_write(sensor, DTT_TEMP_LOW, val))
+ return 1;
+ /*
+ * Setup configuraton register
+ */
+ /* config = alert active low, disabled, and reset */
+ val = 0x64;
+ if (dtt_write(sensor, DTT_CONFIG, val))
+ return 1;
+ /*
+ * Setup control/status register
+ */
+ /* control = temp resolution 0.25C */
+ val = 0x00;
+ if (dtt_write(sensor, DTT_CONTROL, val))
+ return 1;
+
+ dtt_read(sensor, DTT_CONTROL); /* clear temperature flags */
+ 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() */
+
+int dtt_get_temp(int sensor)
+{
+ return (dtt_read(sensor, DTT_READ_TEMP) + 0x0040) >> 7;
+} /* dtt_get_temp() */
+
+#endif /* CONFIG_DTT_LM73 */

index 2e8c690..4e8aaad 100644
@@ -31,7 +31,8 @@
     defined(CONFIG_DTT_DS1621) || \
     defined(CONFIG_DTT_DS1775) || \
     defined(CONFIG_DTT_LM81) || \
-    defined(CONFIG_DTT_ADM1021)
+    defined(CONFIG_DTT_ADM1021) || \
+    defined(CONFIG_DTT_LM73)
 
 #define CONFIG_DTT				/* We have a DTT */
 

@@ -119,4 +120,13 @@ extern int dtt_get_temp(int sensor);
 #define DTT_ADM1021_DEVID	0x41
 #endif
 
+#if defined(CONFIG_DTT_LM73)
+#define DTT_READ_TEMP		0x0
+#define DTT_CONFIG		0x1
+#define DTT_TEMP_HIGH		0x2
+#define DTT_TEMP_LOW		0x3
+#define DTT_CONTROL		0x4
+#define DTT_ID			0x7
+#endif
+
 #endif /* _DTT_H_ */

1.5.2.5

I would like to get those patches accepted and merged in this merge window. We should not delay this by waiting on your conditional compilation rework (which is good of course). So I suggest to get such patches merged right now and fix possible problems with future additions later.

Best regards,
Stefan

=====================================================================
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-0 Fax: +49-8142-66989-80 Email: office at denx.de
=====================================================================

I understand you view but il will great if the new driver could be use conditional Makefile.o

Could you do this modification pls

COBJS-$(CONFIG_DTT_LM73) += lm73.o

instead of

and remove if ifdef CONFIG_DTT_LM73 from the lm73.c

Thanks by advance,
J.

Hi Larry,

Patch seems to be line wrapped. Please fix and resubmit. Thanks.

Best regards,
Stefan

=====================================================================
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-0 Fax: +49-8142-66989-80 Email: office at denx.de
=====================================================================

I noticed that the offending line was part of a check to ensure that the symbol "CFG_EEPROM_PAGE_WRITE_ENABLE" is defined. However, I don't see this switch being used anywhere in the code, although several other HWMON drivers also check that it is defined. Does anyone know of a reason to keep defining it?

Best regards,
Larry