#include <linux/err.h>
#include <linux/sysfs.h>
#include <linux/hwmon.h>
+#include <linux/mutex.h>
+#include <linux/mod_devicetable.h>
#include <linux/spi/spi.h>
-#include <asm/semaphore.h>
+#include <linux/slab.h>
+
#define DRVNAME "lm70"
+#define LM70_CHIP_LM70 0 /* original NS LM70 */
+#define LM70_CHIP_TMP121 1 /* TI TMP121/TMP123 */
+
struct lm70 {
- struct class_device *cdev;
- struct semaphore sem;
+ struct device *hwmon_dev;
+ struct mutex lock;
+ unsigned int chip;
};
/* sysfs hook function */
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);
- if (down_interruptible(&p_lm70->sem))
+ if (mutex_lock_interruptible(&p_lm70->lock))
return -ERESTARTSYS;
/*
"spi_write_then_read failed with status %d\n", status);
goto out;
}
- dev_dbg(dev, "rxbuf[1] : 0x%x rxbuf[0] : 0x%x\n", rxbuf[1], rxbuf[0]);
-
- raw = (rxbuf[1] << 8) + rxbuf[0];
- dev_dbg(dev, "raw=0x%x\n", raw);
+ raw = (rxbuf[0] << 8) + rxbuf[1];
+ dev_dbg(dev, "rxbuf[0] : 0x%02x rxbuf[1] : 0x%02x raw=0x%04x\n",
+ 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.
* 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;
- status = sprintf(buf, "%+d\n", val); /* millidegrees 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:
- up(&p_lm70->sem);
+ mutex_unlock(&p_lm70->lock);
return status;
}
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)
+{
+ 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)
{
+ int chip = spi_get_device_id(spi)->driver_data;
struct lm70 *p_lm70;
int status;
+ /* signaling is SPI_MODE_0 for both LM70 and TMP121 */
+ if (spi->mode & (SPI_CPOL | SPI_CPHA))
+ return -EINVAL;
+
+ /* 3-wire link (shared SI/SO) for LM70 */
+ if (chip == LM70_CHIP_LM70 && !(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);
if (!p_lm70)
return -ENOMEM;
- init_MUTEX(&p_lm70->sem);
+ mutex_init(&p_lm70->lock);
+ p_lm70->chip = chip;
/* sysfs hook */
- p_lm70->cdev = hwmon_device_register(&spi->dev);
- if (IS_ERR(p_lm70->cdev)) {
+ p_lm70->hwmon_dev = hwmon_device_register(&spi->dev);
+ if (IS_ERR(p_lm70->hwmon_dev)) {
dev_dbg(&spi->dev, "hwmon_device_register failed.\n");
- status = PTR_ERR(p_lm70->cdev);
+ status = PTR_ERR(p_lm70->hwmon_dev);
goto out_dev_reg_failed;
}
dev_set_drvdata(&spi->dev, p_lm70);
- if ((status = device_create_file(&spi->dev, &dev_attr_temp1_input))) {
+ if ((status = device_create_file(&spi->dev, &dev_attr_temp1_input))
+ || (status = device_create_file(&spi->dev, &dev_attr_name))) {
dev_dbg(&spi->dev, "device_create_file failure.\n");
goto out_dev_create_file_failed;
}
return 0;
out_dev_create_file_failed:
- hwmon_device_unregister(p_lm70->cdev);
+ device_remove_file(&spi->dev, &dev_attr_temp1_input);
+ hwmon_device_unregister(p_lm70->hwmon_dev);
out_dev_reg_failed:
dev_set_drvdata(&spi->dev, NULL);
kfree(p_lm70);
struct lm70 *p_lm70 = dev_get_drvdata(&spi->dev);
device_remove_file(&spi->dev, &dev_attr_temp1_input);
- hwmon_device_unregister(p_lm70->cdev);
+ device_remove_file(&spi->dev, &dev_attr_name);
+ hwmon_device_unregister(p_lm70->hwmon_dev);
dev_set_drvdata(&spi->dev, NULL);
kfree(p_lm70);
return 0;
}
+
+static const struct spi_device_id lm70_ids[] = {
+ { "lm70", LM70_CHIP_LM70 },
+ { "tmp121", LM70_CHIP_TMP121 },
+ { },
+};
+MODULE_DEVICE_TABLE(spi, lm70_ids);
+
static struct spi_driver lm70_driver = {
.driver = {
.name = "lm70",
.owner = THIS_MODULE,
},
+ .id_table = lm70_ids,
.probe = lm70_probe,
.remove = __devexit_p(lm70_remove),
};
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");