hwmon: Add LM63 support

This patch adds support for the National LM63 temperature
sensor with integrated fan control. It's used on the GDSys
Neo board (405EP) which will be submitted later.

Signed-off-by: Dirk Eibach <eibach@gdsys.de>
Acked-by: Stefan Roese <sr@denx.de>

1 files changed, 174 insertions, 0 deletions

diff --git a/drivers/hwmon/lm63.c b/drivers/hwmon/lm63.c
new file mode 100644
index 0000000..03616e1
--- /dev/null
+++ b/drivers/hwmon/lm63.c
@@ -0,0 +1,174 @@
+/*
+ * (C) Copyright 2007-2008
+ * Dirk Eibach,  Guntermann & Drunck GmbH, eibach@gdsys.de
+ * based on lm75.c by Bill Hunter
+ *
+ * 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 LM63 Temperature Sensor
+ */
+
+#include <common.h>
+#include <i2c.h>
+#include <dtt.h>
+
+#define DTT_I2C_DEV_CODE 0x4C	/* National LM63 device */
+
+#define DTT_READ_TEMP_RMT_MSB	0x01
+#define DTT_CONFIG		0x03
+#define DTT_READ_TEMP_RMT_LSB	0x10
+#define DTT_TACHLIM_LSB		0x48
+#define DTT_TACHLIM_MSB		0x49
+#define DTT_FAN_CONFIG		0x4A
+#define DTT_PWM_FREQ		0x4D
+#define DTT_PWM_LOOKUP_BASE	0x50
+
+struct pwm_lookup_entry {
+	u8 temp;
+	u8 pwm;
+};
+
+/*
+ * Device code
+ */
+
+int dtt_read(int sensor, int reg)
+{
+	int dlen;
+	uchar data[2];
+
+	/*
+	 * Calculate sensor address and register.
+	 */
+	sensor = DTT_I2C_DEV_CODE;	/* address of lm63 is not adjustable */
+
+	dlen = 1;
+
+	/*
+	 * 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)
+{
+	int dlen;
+	uchar data[2];
+
+	/*
+	 * Calculate sensor address and register.
+	 */
+	sensor = DTT_I2C_DEV_CODE;	/* address of lm63 is not adjustable */
+
+	dlen = 1;
+	data[0] = (char)(val & 0xff);
+
+	/*
+	 * Write value to register.
+	 */
+	if (i2c_write(sensor, reg, 1, data, dlen) != 0)
+		return 1;
+
+	return 0;
+}				/* dtt_write() */
+
+static int _dtt_init(int sensor)
+{
+	int i;
+	int val;
+
+	struct pwm_lookup_entry pwm_lookup[] = CONFIG_DTT_PWM_LOOKUPTABLE;
+
+	/*
+	 * Set PWM Frequency to 2.5% resolution
+	 */
+	val = 20;
+	if (dtt_write(sensor, DTT_PWM_FREQ, val) != 0)
+		return 1;
+
+	/*
+	 * Set Tachometer Limit
+	 */
+	val = CONFIG_DTT_TACH_LIMIT;
+	if (dtt_write(sensor, DTT_TACHLIM_LSB, val & 0xff) != 0)
+		return 1;
+	if (dtt_write(sensor, DTT_TACHLIM_MSB, (val >> 8) & 0xff) != 0)
+		return 1;
+
+	/*
+	 * Setup PWM Lookup-Table
+	 */
+	for (i = 0; i < sizeof(pwm_lookup) / sizeof(struct pwm_lookup_entry);
+	     i++) {
+		int address = DTT_PWM_LOOKUP_BASE + 2 * i;
+		val = pwm_lookup[i].temp;
+		if (dtt_write(sensor, address, val) != 0)
+			return 1;
+		val = pwm_lookup[i].pwm;
+		if (dtt_write(sensor, address + 1, val) != 0)
+			return 1;
+	}
+
+	/*
+	 * Enable PWM Lookup-Table, PWM Clock 360 kHz, Tachometer Mode 2
+	 */
+	val = 0x02;
+	if (dtt_write(sensor, DTT_FAN_CONFIG, val) != 0)
+		return 1;
+
+	/*
+	 * Enable Tach input
+	 */
+	val = dtt_read(sensor, DTT_CONFIG) | 0x04;
+	if (dtt_write(sensor, DTT_CONFIG, val) != 0)
+		return 1;
+
+	return 0;
+}
+
+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));
+
+	/* Ignore LSB for now, U-Boot only prints natural numbers */
+	return temp >> 8;
+}
+
+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;
+}