hwmon: Extend lm63.c to support LM64

This patch adds support for the National LM64 temperature
sensor with integrated fan control to lm63.c.
Main difference between LM63 and LM64 is 16°C offset in sensor
readings.

Signed-off-by: Dirk Eibach <eibach@gdsys.de>

diff --git a/drivers/hwmon/lm63.c b/drivers/hwmon/lm63.c
index 03616e183a22072e6ef00a81f1c5cb92a3fa5d80..2f1f3cfabf2086ecba00275582a7351eb16d2b4d 100644 (file)
--- a/drivers/hwmon/lm63.c
+++ b/drivers/hwmon/lm63.c
@@ -23,14 +23,15 @@
  */
 
 /*
- * National LM63 Temperature Sensor
+ * National LM63/LM64 Temperature Sensor
+ * Main difference: LM 64 has -16 Kelvin temperature offset
  */
 
 #include <common.h>
 #include <i2c.h>
 #include <dtt.h>
 
-#define DTT_I2C_DEV_CODE 0x4C  /* National LM63 device */
+#define DTT_I2C_LM63_ADDR      0x4C    /* National LM63 device */
 
 #define DTT_READ_TEMP_RMT_MSB  0x01
 #define DTT_CONFIG             0x03
@@ -58,7 +59,8 @@ int dtt_read(int sensor, int reg)
        /*
         * Calculate sensor address and register.
         */
-       sensor = DTT_I2C_DEV_CODE;      /* address of lm63 is not adjustable */
+       if (!sensor)
+               sensor = DTT_I2C_LM63_ADDR;     /* legacy config */
 
        dlen = 1;
 
@@ -79,7 +81,8 @@ int dtt_write(int sensor, int reg, int val)
        /*
         * Calculate sensor address and register.
         */
-       sensor = DTT_I2C_DEV_CODE;      /* address of lm63 is not adjustable */
+       if (!sensor)
+               sensor = DTT_I2C_LM63_ADDR;     /* legacy config */
 
        dlen = 1;
        data[0] = (char)(val & 0xff);
@@ -93,6 +96,11 @@ int dtt_write(int sensor, int reg, int val)
        return 0;
 }                              /* dtt_write() */
 
+static int is_lm64(int sensor)
+{
+       return sensor && (sensor != DTT_I2C_LM63_ADDR);
+}
+
 static int _dtt_init(int sensor)
 {
        int i;
@@ -116,6 +124,12 @@ static int _dtt_init(int sensor)
        if (dtt_write(sensor, DTT_TACHLIM_MSB, (val >> 8) & 0xff) != 0)
                return 1;
 
+       /*
+        * Make sure PWM Lookup-Table is writeable
+        */
+       if (dtt_write(sensor, DTT_FAN_CONFIG, 0x20) != 0)
+               return 1;
+
        /*
         * Setup PWM Lookup-Table
         */
@@ -123,8 +137,11 @@ static int _dtt_init(int sensor)
             i++) {
                int address = DTT_PWM_LOOKUP_BASE + 2 * i;
                val = pwm_lookup[i].temp;
+               if (is_lm64(sensor))
+                       val -= 16;
                if (dtt_write(sensor, address, val) != 0)
                        return 1;
+               val = dtt_read(sensor, address);
                val = pwm_lookup[i].pwm;
                if (dtt_write(sensor, address + 1, val) != 0)
                        return 1;
@@ -152,6 +169,9 @@ int dtt_get_temp(int sensor)
        s16 temp = (dtt_read(sensor, DTT_READ_TEMP_RMT_MSB) << 8)
            | (dtt_read(sensor, DTT_READ_TEMP_RMT_LSB));
 
+       if (is_lm64(sensor))
+               temp += 16 << 8;
+
        /* Ignore LSB for now, U-Boot only prints natural numbers */
        return temp >> 8;
 }