[people/ms/u-boot.git] / drivers / hwmon / ds1775.c

/*
 * 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
 */

/*
 * Dallas Semiconductor's DS1775 Digital Thermometer and Thermostat
 */

#include <common.h>

#ifdef CONFIG_DTT_DS1775
#include <i2c.h>
#include <dtt.h>

#define DTT_I2C_DEV_CODE	CFG_I2C_DTT_ADDR /* Dallas Semi's DS1775 device code */

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 ds1775 */

	/*
	 * Prepare to handle 2 byte result
	 */
	if ((reg == DTT_READ_TEMP) ||
	    (reg == DTT_TEMP_OS) || (reg == DTT_TEMP_HYST))
		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];
}


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_OS) || (reg == DTT_TEMP_HYST)) {
		dlen = 2;
		data[0] = (char)((val >> 8) & 0xff); /* MSB first */
		data[1] = (char)(val & 0xff);
	} 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;
}


static int _dtt_init(int sensor)
{
	int val;

	/*
	 * Setup High Temp
	 */
	val = ((CFG_DTT_MAX_TEMP * 2) << 7) & 0xff80;
	if (dtt_write(sensor, DTT_TEMP_OS, val) != 0)
		return 1;
	udelay(50000);			/* Max 50ms */

	/*
	 * Setup Low Temp - hysteresis
	 */
	val = (((CFG_DTT_MAX_TEMP - CFG_DTT_HYSTERESIS) * 2) << 7) & 0xff80;
	if (dtt_write(sensor, DTT_TEMP_HYST, val) != 0)
		return 1;
	udelay(50000);			/* Max 50ms */

	/*
	 * Setup configuraton register
	 *
	 * Fault Tolerance limits 4, Thermometer resolution bits is 9,
	 * Polarity = Active Low,continuous conversion mode, Thermostat
	 * mode is interrupt mode
	 */
	val = 0xa;
	if (dtt_write(sensor, DTT_CONFIG, val) != 0)
		return 1;
	udelay(50000);			/* Max 50ms */

	return 0;
}


int dtt_init (void)
{
	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]));
	}

	return (0);
}


int dtt_get_temp(int sensor)
{
	return (dtt_read(sensor, DTT_READ_TEMP) / 256);
}


#endif /* CONFIG_DTT_DS1775 */
Commit	Line	Data
d4024bb7 JO	1	/*
	2	* This program is free software; you can redistribute it and/or
	3	* modify it under the terms of the GNU General Public License as
	4	* published by the Free Software Foundation; either version 2 of
	5	* the License, or (at your option) any later version.
	6	*
	7	* This program is distributed in the hope that it will be useful,
	8	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	9	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	10	* GNU General Public License for more details.
	11	*
	12	* You should have received a copy of the GNU General Public License
	13	* along with this program; if not, write to the Free Software
	14	* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
	15	* MA 02111-1307 USA
	16	*/
	17
	18	/*
	19	* Dallas Semiconductor's DS1775 Digital Thermometer and Thermostat
	20	*/
	21
	22	#include <common.h>
	23
	24	#ifdef CONFIG_DTT_DS1775
	25	#include <i2c.h>
	26	#include <dtt.h>
	27
4f2e92c1	28	#define DTT_I2C_DEV_CODE CFG_I2C_DTT_ADDR /* Dallas Semi's DS1775 device code */
d4024bb7 JO	29
	30	int dtt_read(int sensor, int reg)
	31	{
	32	int dlen;
	33	uchar data[2];
	34
	35	/*
	36	* Calculate sensor address and command
	37	*/
	38	sensor = DTT_I2C_DEV_CODE + (sensor & 0x07); /* Calculate addr of ds1775 */
	39
	40	/*
	41	* Prepare to handle 2 byte result
	42	*/
	43	if ((reg == DTT_READ_TEMP) \|\|
	44	(reg == DTT_TEMP_OS) \|\| (reg == DTT_TEMP_HYST))
	45	dlen = 2;
	46	else
	47	dlen = 1;
	48
	49	/*
	50	* Now try to read the register
	51	*/
	52	if (i2c_read(sensor, reg, 1, data, dlen) != 0)
	53	return 1;
	54
	55	/*
	56	* Handle 2 byte result
	57	*/
	58	if (dlen == 2)
	59	return ((int)((short)data[1] + (((short)data[0]) << 8)));
	60
	61	return (int) data[0];
	62	}
	63
	64
	65	int dtt_write(int sensor, int reg, int val)
	66	{
	67	int dlen;
	68	uchar data[2];
	69
	70	/*
	71	* Calculate sensor address and register
	72	*/
	73	sensor = DTT_I2C_DEV_CODE + (sensor & 0x07);
	74
	75	/*
	76	* Handle various data sizes
	77	*/
	78	if ((reg == DTT_READ_TEMP) \|\|
	79	(reg == DTT_TEMP_OS) \|\| (reg == DTT_TEMP_HYST)) {
	80	dlen = 2;
	81	data[0] = (char)((val >> 8) & 0xff); /* MSB first */
	82	data[1] = (char)(val & 0xff);
	83	} else {
	84	dlen = 1;
	85	data[0] = (char)(val & 0xff);
	86	}
	87
	88	/*
	89	* Write value to device
	90	*/
	91	if (i2c_write(sensor, reg, 1, data, dlen) != 0)
	92	return 1;
93
94	return 0;
95	}
96
97
98	static int _dtt_init(int sensor)
99	{
100	int val;
101
102	/*
103	* Setup High Temp
104	*/
105	val = ((CFG_DTT_MAX_TEMP * 2) << 7) & 0xff80;
106	if (dtt_write(sensor, DTT_TEMP_OS, val) != 0)
107	return 1;
108	udelay(50000); /* Max 50ms */
109
110	/*
111	* Setup Low Temp - hysteresis
112	*/
113	val = (((CFG_DTT_MAX_TEMP - CFG_DTT_HYSTERESIS) * 2) << 7) & 0xff80;
114	if (dtt_write(sensor, DTT_TEMP_HYST, val) != 0)
115	return 1;
116	udelay(50000); /* Max 50ms */
117
118	/*
119	* Setup configuraton register
120	*
121	* Fault Tolerance limits 4, Thermometer resolution bits is 9,
122	* Polarity = Active Low,continuous conversion mode, Thermostat
123	* mode is interrupt mode
124	*/
125	val = 0xa;
126	if (dtt_write(sensor, DTT_CONFIG, val) != 0)
127	return 1;
128	udelay(50000); /* Max 50ms */
129
130	return 0;
131	}
132
133
134	int dtt_init (void)
135	{
136	int i;
137	unsigned char sensors[] = CONFIG_DTT_SENSORS;
138
139	for (i = 0; i < sizeof(sensors); i++) {
140	if (_dtt_init(sensors[i]) != 0)
141	printf("DTT%d: FAILED\n", i+1);
142	else
143	printf("DTT%d: %i C\n", i+1, dtt_get_temp(sensors[i]));
144	}
145
146	return (0);
147	}
148
149
150	int dtt_get_temp(int sensor)
151	{
152	return (dtt_read(sensor, DTT_READ_TEMP) / 256);
153	}
154
155
156	#endif /* CONFIG_DTT_DS1775 */