--- /dev/null
+/****************************************************************************
+ * drivers/temp.c
+ *
+ *
+ * Copyright 2012 Nathael Pajani <nathael.pajani@ed3l.fr>
+ *
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ *
+ *************************************************************************** */
+
+#include <stdint.h>
+
+#include "core/lpc_regs_12xx.h"
+#include "core/lpc_core_cm0.h"
+#include "core/system.h"
+#include "drivers/i2c.h"
+#include "drivers/temp.h"
+
+
+/***************************************************************************** */
+/* Support for TMP101 temperature sensors from Texas Instrument */
+/***************************************************************************** */
+/* This driver is made for the TMP101 version of the chip, though there's few
+ * diferences between the TMP100 and TMP101 version.
+ * This driver does not handle the SMBus Alert command.
+ */
+
+
+/* Config */
+#define TMP101_ADDR 0x94
+
+enum tmp10x_internal_reg_numbers {
+ TMP_REG_TEMPERATURE = 0,
+ TMP_REG_CONFIG,
+ TMP_REG_ALERT_LOW,
+ TMP_REG_ALERT_HIGH,
+};
+
+
+/* Aditional defines, not exported to userspace */
+/* Mode config */
+#define TMP_SHUTDOWN_MODE_ON (1 << 0)
+#define TMP_THERMOSTAT_COMPARATOR_MODE (0 << 1)
+#define TMP_THERMOSTAT_INTERRUPT_MODE (1 << 1)
+/* Alert signal polarity */
+#define TMP_ALERT_POLARITY_LOW (0 << 2)
+#define TMP_ALERT_POLARITY_HIGH (1 << 2)
+/* One-shot measurement trigger */
+#define TMP_ONE_SHOT_TRIGGER (1 << 7)
+
+
+
+/* This static value is used to keep track of the last register accessed to
+ * prevent sending the pointer register again if we want to read the same
+ * register again. */
+static int last_accessed_register = 0;
+
+/* Check the sensor presence, return 1 if sensor was found.
+ * This is a basic check, it could be anything with the same address ...
+ */
+int probe_sensor(void)
+{
+ static int ret = -1;
+ char cmd_buf[1] = { (TMP101_ADDR | I2C_READ_BIT), };
+
+ /* Did we already probe the sensor ? */
+ if (ret != 1) {
+ ret = i2c_read(cmd_buf, 1, NULL, NULL, 0);
+ }
+ return ret;
+}
+
+/* Convert raw temperature data (expressed as signed value of 16 times the
+ * actual temperature in the twelve higher bits of a sixteen bits wide value)
+ * into a decimal interger value of ten times the actual temperature.
+ * The value returned is thus in tenth of degrees centigrade.
+ */
+int convert_to_deci_degrees(uint16_t raw)
+{
+ uint16_t val = ((raw >> 4) & 0x07FF);
+ int sign = 1;
+
+ if (raw & 0x8000) {
+ sign = -1;
+ val = ~(val) + 1;
+ }
+ return (sign * (((int)val * 10) / 16));
+}
+
+/* Temp Read
+ * Performs a non-blocking read of the temperature from the sensor.
+ * RETURN VALUE
+ * Upon successfull completion, returns 0 and the temperature read is placed in the
+ * provided integer. On error, returns a negative integer equivalent to errors from glibc.
+ * -EBADFD : I2C not initialized
+ * -EBUSY : Device or ressource Busy or Arbitration lost
+ * -EINVAL : Invalid argument (buf)
+ * -ENODEV : No such device
+ * -EREMOTEIO : Device did not acknowledge : Any device present ?
+ * -EIO : Bad one: Illegal start or stop, or illegal state in i2c state machine
+ */
+#define CMD_BUF_SIZE 3
+int temp_read(uint16_t* raw, int* deci_degrees)
+{
+ int ret = 0;
+ uint16_t temp = 0;
+ char cmd_buf[CMD_BUF_SIZE] = { TMP101_ADDR, TMP_REG_TEMPERATURE, (TMP101_ADDR | I2C_READ_BIT), };
+ char ctrl_buf[CMD_BUF_SIZE] = { I2C_CONT, I2C_DO_REPEATED_START, I2C_CONT, };
+
+ if (probe_sensor() != 1) {
+ return -ENODEV;
+ }
+
+ /* Read the requested data */
+ if (last_accessed_register == TMP_REG_TEMPERATURE) {
+ /* No need to switch back to temperature register */
+ ret = i2c_read((cmd_buf + 2), 1, (ctrl_buf + 2), (char*)&temp, 2);
+ } else {
+ /* Send (write) temperature register address to TMP101 internal pointer */
+ ret = i2c_read(cmd_buf, CMD_BUF_SIZE, ctrl_buf, (char*)&temp, 2);
+ }
+
+ if (ret == 2) {
+ if (raw != NULL) {
+ *raw = byte_swap_16(temp);
+ }
+ if (deci_degrees != NULL) {
+ *deci_degrees = convert_to_deci_degrees(byte_swap_16(temp));
+ }
+ return 0;
+ }
+ return ret;
+}
+
+
+/* Sensor config
+ * Performs default configuration of the temperature sensor.
+ * The sensor is thus placed in shutdown mode, the thermostat is in interrupt mode,
+ * and the polarity is set to active high.
+ * The conversion resolution is set to the provided "resolution".
+ * RETURN VALUE
+ * Upon successfull completion, returns 0. On error, returns a negative integer
+ * equivalent to errors from glibc.
+ * -EBADFD : I2C not initialized
+ * -EBUSY : Device or ressource Busy or Arbitration lost
+ * -EINVAL : Invalid argument (buf)
+ * -ENODEV : No such device
+ * -EREMOTEIO : Device did not acknowledge : Any device present ?
+ * -EIO : Bad one: Illegal start or stop, or illegal state in i2c state machine
+ */
+static uint8_t actual_config = 0;
+#define CONF_BUF_SIZE 4
+int sensor_config(uint32_t resolution)
+{
+ int ret = 0;
+ char cmd[CONF_BUF_SIZE] = { TMP101_ADDR, TMP_REG_CONFIG, };
+
+ if (probe_sensor() != 1) {
+ return -ENODEV;
+ }
+
+ /* Store the new configuration */
+ actual_config = (TMP_SHUTDOWN_MODE_ON | TMP_THERMOSTAT_INTERRUPT_MODE | TMP_ALERT_POLARITY_HIGH);
+ actual_config |= (resolution & (0x03 << 5));
+ cmd[2] = actual_config;
+ ret = i2c_write(cmd, 3, NULL);
+ last_accessed_register = TMP_REG_CONFIG;
+ if (ret == 3) {
+ return 0; /* Config success */
+ }
+ return ret;
+}
+
+/* Start a conversion when the sensor is in shutdown mode. */
+int sensor_start_conversion(void)
+{
+ int ret = 0;
+ char cmd[CONF_BUF_SIZE] = { TMP101_ADDR, TMP_REG_CONFIG, };
+
+ if (probe_sensor() != 1) {
+ return -ENODEV;
+ }
+
+ cmd[2] = actual_config;
+ cmd[2] |= TMP_ONE_SHOT_TRIGGER;
+ ret = i2c_write(cmd, 3, NULL);
+ last_accessed_register = TMP_REG_CONFIG;
+ if (ret == 3) {
+ return 0; /* Conversion start success */
+ }
+ return ret;
+}
+
+
--- /dev/null
+/****************************************************************************
+ * drivers/temp.h
+ *
+ *
+ * Copyright 2012 Nathael Pajani <nathael.pajani@ed3l.fr>
+ *
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ *
+ *************************************************************************** */
+
+#include <stdint.h>
+
+
+/***************************************************************************** */
+/* Support for TMP101 temperature sensors from Texas Instrument */
+/***************************************************************************** */
+/* This driver is made for the TMP101 version of the chip, though there's few
+ * diferences between the TMP100 and TMP101 version.
+ * This driver does not handle the SMBus Alert command.
+ */
+
+
+/* Faulty mesures required to trigger alert */
+#define TMP_FAULT_ONE ((0x00 & 0x03) << 3)
+#define TMP_FAULT_TWO ((0x01 & 0x03) << 3)
+#define TMP_FAULT_FOUR ((0x02 & 0x03) << 3)
+#define TMP_FAULT_SIX ((0x03 & 0x03) << 3)
+
+/* Temp mesurement resolution bits */ /* conversion time */
+#define TMP_RES_NINE_BITS ((0x00 & 0x03) << 5) /* 40ms */
+#define TMP_RES_TEN_BITS ((0x01 & 0x03) << 5) /* 80ms */
+#define TMP_RES_ELEVEN_BITS ((0x02 & 0x03) << 5) /* 160ms */
+#define TMP_RES_TWELVE_BITS ((0x03 & 0x03) << 5) /* 320ms */
+
+
+/* Check the sensor presence, return 1 if found
+ * This is a basic check, it could be anything with the same address ...
+ */
+int probe_sensor(void);
+
+
+/* Convert raw temperature data (expressed as signed value of 16 times the
+ * actual temperature in the twelve higher bits of a sixteen bits wide value)
+ * into a decimal interger value of ten times the actual temperature.
+ * The value returned is thus in tenth of degrees centigrade.
+ */
+int convert_to_deci_degrees(uint16_t raw);
+
+
+/* Temp Read
+ * Performs a non-blocking read of the temperature from the sensor.
+ * RETURN VALUE
+ * Upon successfull completion, returns 0 and the temperature read is placed in the
+ * provided integer(s). On error, returns a negative integer equivalent to errors from
+ * glibc.
+ * -EBADFD : I2C not initialized
+ * -EBUSY : Device or ressource Busy or Arbitration lost
+ * -EINVAL : Invalid argument (buf)
+ * -ENODEV : No such device
+ * -EREMOTEIO : Device did not acknowledge : Any device present ?
+ * -EIO : Bad one: Illegal start or stop, or illegal state in i2c state machine
+ */
+int temp_read(uint16_t* raw, int* deci_degrees);
+
+
+/* Sensor config
+ * Performs default configuration of the temperature sensor.
+ * The sensor is thus placed in shutdown mode, the thermostat is in interrupt mode,
+ * and the polarity is set to active high.
+ * The conversion resolution is set to the provided "resolution".
+ * RETURN VALUE
+ * Upon successfull completion, returns 0. On error, returns a negative integer
+ * equivalent to errors from glibc.
+ * -EBADFD : I2C not initialized
+ * -EBUSY : Device or ressource Busy or Arbitration lost
+ * -EINVAL : Invalid argument (buf)
+ * -ENODEV : No such device
+ * -EREMOTEIO : Device did not acknowledge : Any device present ?
+ * -EIO : Bad one: Illegal start or stop, or illegal state in i2c state machine
+ */
+int sensor_config(uint32_t resolution);
+
+/* Start a conversion when the sensor is in shutdown mode. */
+int sensor_start_conversion(void);
+
+
