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Commit c8ac32e4 authored by Manuel Lauss's avatar Manuel Lauss Committed by Jean Delvare
Browse files

hwmon: (lm70) Add TI TMP121 support 



The Texas Instruments TMP121 is a SPI temperature sensor very similar
to the LM70, with slightly higher resolution.  This patch extends the
LM70 driver to support the TMP121.  The TMP123 differs in pin assign-
ment.

Signed-off-by: default avatarManuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
parent 2b730051

Documentation/hwmon/lm70

+7 −1
Original line number Diff line number Diff line 
Kernel driver lm70

==================



Supported chip:

Supported chips:

  * National Semiconductor LM70

    Datasheet: http://www.national.com/pf/LM/LM70.html

  * Texas Instruments TMP121/TMP123

    Information: http://focus.ti.com/docs/prod/folders/print/tmp121.html



Author:

        Kaiwan N Billimoria <kaiwan@designergraphix.com>
@@ -29,6 +31,10 @@ As a real (in-tree) example of this "SPI protocol driver" interfacing 
with a "SPI master controller driver", see drivers/spi/spi_lm70llp.c

and its associated documentation.



The TMP121/TMP123 are very similar; main differences are 4 wire SPI inter-

face (read only) and 13-bit temperature data (0.0625 degrees celsius reso-

lution).



Thanks to

---------

Jean Delvare <khali@linux-fr.org> for mentoring the hwmon-side driver

drivers/hwmon/Kconfig

+3 −2
Original line number Diff line number Diff line
@@ -428,11 +428,12 @@ config SENSORS_LM63 
	  will be called lm63.



config SENSORS_LM70

	tristate "National Semiconductor LM70"

	tristate "National Semiconductor LM70 / Texas Instruments TMP121"

	depends on SPI_MASTER && EXPERIMENTAL

	help

	  If you say yes here you get support for the National Semiconductor

	  LM70 digital temperature sensor chip.

	  LM70 and Texas Instruments TMP121/TMP123 digital temperature

	  sensor chips.



	  This driver can also be built as a module.  If so, the module

	  will be called lm70.

drivers/hwmon/lm70.c

+74 −10
Original line number Diff line number Diff line
@@ -37,9 +37,13 @@ 


#define DRVNAME		"lm70"



#define LM70_CHIP_LM70		0	/* original NS LM70 */

#define LM70_CHIP_TMP121	1	/* TI TMP121/TMP123 */



struct lm70 {

	struct device *hwmon_dev;

	struct mutex lock;

	unsigned int chip;

};



/* sysfs hook function */
@@ -47,7 +51,7 @@ static ssize_t lm70_sense_temp(struct device *dev, 
		struct device_attribute *attr, char *buf)

{

	struct spi_device *spi = to_spi_device(dev);

	int status, val;

	int status, val = 0;

	u8 rxbuf[2];

	s16 raw=0;

	struct lm70 *p_lm70 = dev_get_drvdata(&spi->dev);
@@ -70,6 +74,7 @@ static ssize_t lm70_sense_temp(struct device *dev, 
		rxbuf[0], rxbuf[1], raw);



	/*

	 * LM70:

	 * The "raw" temperature read into rxbuf[] is a 16-bit signed 2's

	 * complement value. Only the MSB 11 bits (1 sign + 10 temperature

	 * bits) are meaningful; the LSB 5 bits are to be discarded.
@@ -79,8 +84,21 @@ static ssize_t lm70_sense_temp(struct device *dev, 
	 * by 0.25. Also multiply by 1000 to represent in millidegrees

	 * Celsius.

	 * So it's equivalent to multiplying by 0.25 * 1000 = 250.

	 *

	 * TMP121/TMP123:

	 * 13 bits of 2's complement data, discard LSB 3 bits,

	 * resolution 0.0625 degrees celsius.

	 */

	switch (p_lm70->chip) {

	case LM70_CHIP_LM70:

		val = ((int)raw / 32) * 250;

		break;



	case LM70_CHIP_TMP121:

		val = ((int)raw / 8) * 625 / 10;

		break;

	}



	status = sprintf(buf, "%d\n", val); /* millidegrees Celsius */

out:

	mutex_unlock(&p_lm70->lock);
@@ -92,22 +110,31 @@ static DEVICE_ATTR(temp1_input, S_IRUGO, lm70_sense_temp, NULL); 
static ssize_t lm70_show_name(struct device *dev, struct device_attribute

			      *devattr, char *buf)

{

	return sprintf(buf, "lm70\n");

	struct lm70 *p_lm70 = dev_get_drvdata(dev);

	int ret;



	switch (p_lm70->chip) {

	case LM70_CHIP_LM70:

		ret = sprintf(buf, "lm70\n");

		break;

	case LM70_CHIP_TMP121:

		ret = sprintf(buf, "tmp121\n");

		break;

	default:

		ret = -EINVAL;

	}

	return ret;

}



static DEVICE_ATTR(name, S_IRUGO, lm70_show_name, NULL);



/*----------------------------------------------------------------------*/



static int __devinit lm70_probe(struct spi_device *spi)

static int __devinit common_probe(struct spi_device *spi, int chip)

{

	struct lm70 *p_lm70;

	int status;



	/* signaling is SPI_MODE_0 on a 3-wire link (shared SI/SO) */

	if ((spi->mode & (SPI_CPOL|SPI_CPHA)) || !(spi->mode & SPI_3WIRE))

		return -EINVAL;



	/* NOTE:  we assume 8-bit words, and convert to 16 bits manually */



	p_lm70 = kzalloc(sizeof *p_lm70, GFP_KERNEL);
@@ -115,6 +142,7 @@ static int __devinit lm70_probe(struct spi_device *spi) 
		return -ENOMEM;



	mutex_init(&p_lm70->lock);

	p_lm70->chip = chip;



	/* sysfs hook */

	p_lm70->hwmon_dev = hwmon_device_register(&spi->dev);
@@ -142,6 +170,24 @@ static int __devinit lm70_probe(struct spi_device *spi) 
	return status;

}



static int __devinit lm70_probe(struct spi_device *spi)

{

	/* signaling is SPI_MODE_0 on a 3-wire link (shared SI/SO) */

	if ((spi->mode & (SPI_CPOL | SPI_CPHA)) || !(spi->mode & SPI_3WIRE))

		return -EINVAL;



	return common_probe(spi, LM70_CHIP_LM70);

}



static int __devinit tmp121_probe(struct spi_device *spi)

{

	/* signaling is SPI_MODE_0 with only MISO connected */

	if (spi->mode & (SPI_CPOL | SPI_CPHA))

		return -EINVAL;



	return common_probe(spi, LM70_CHIP_TMP121);

}



static int __devexit lm70_remove(struct spi_device *spi)

{

	struct lm70 *p_lm70 = dev_get_drvdata(&spi->dev);
@@ -155,6 +201,15 @@ static int __devexit lm70_remove(struct spi_device *spi) 
	return 0;

}



static struct spi_driver tmp121_driver = {

	.driver = {

		.name	= "tmp121",

		.owner	= THIS_MODULE,

	},

	.probe	= tmp121_probe,

	.remove	= __devexit_p(lm70_remove),

};



static struct spi_driver lm70_driver = {

	.driver = {

		.name	= "lm70",
@@ -166,17 +221,26 @@ static struct spi_driver lm70_driver = { 


static int __init init_lm70(void)

{

	return spi_register_driver(&lm70_driver);

	int ret = spi_register_driver(&lm70_driver);

	if (ret)

		return ret;



	ret = spi_register_driver(&tmp121_driver);

	if (ret)

		spi_unregister_driver(&lm70_driver);



	return ret;

}



static void __exit cleanup_lm70(void)

{

	spi_unregister_driver(&lm70_driver);

	spi_unregister_driver(&tmp121_driver);

}



module_init(init_lm70);

module_exit(cleanup_lm70);



MODULE_AUTHOR("Kaiwan N Billimoria");

MODULE_DESCRIPTION("National Semiconductor LM70 Linux driver");

MODULE_DESCRIPTION("NS LM70 / TI TMP121/TMP123 Linux driver");

MODULE_LICENSE("GPL");