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: Manuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
diff --git a/drivers/hwmon/lm70.c b/drivers/hwmon/lm70.c
index 9f9741b..ae6204f 100644
--- a/drivers/hwmon/lm70.c
+++ b/drivers/hwmon/lm70.c
@@ -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 @@
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 @@
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 @@
* 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.
*/
- val = ((int)raw/32) * 250;
+ 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 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 @@
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 @@
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 @@
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 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");