/*
* Copyright (c) 2016-2017 Chris Johns <chrisj@rtems.org>
* All rights reserved.
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdio.h>
#include <dev/i2c/i2c.h>
#include <dev/i2c/ti-tmp112.h>
/*
* Registers.
*/
#define TMP_TEMPERATURE (0)
#define TMP_CONFIG (1)
#define TMP_LOW_TEMP (2)
#define TMP_HIGH_TEMP (3)
/*
* Configuration register.
*/
#define CFG_ONE_SHOT_BASE (15)
#define CFG_SHUTDOWN_BASE (8)
#define CFG_EXTENDED_MODE_BASE (4)
#define CFG_ONE_SHOT (1 << CFG_ONE_SHOT_BASE)
#define CFG_SHUTDOWN (1 << CFG_SHUTDOWN_BASE)
#define CFG_EXTENDED_MODE (1 << CFG_EXTENDED_MODE_BASE)
typedef struct {
i2c_dev base;
uint8_t pointer;
uint16_t config_shadow;
} ti_tmp112;
static int
ti_tmp112_reg_write(ti_tmp112* dev, int reg, uint16_t value)
{
uint8_t out[3];
i2c_msg msgs[1] = {
{
.addr = dev->base.address,
.flags = 0,
.len = (uint16_t) sizeof(out),
.buf = &out[0]
}
};
int err;
if (dev->pointer == reg) {
out[0] = (uint8_t) (value >> 8);
out[1] = (uint8_t) value;
msgs[0].len = 2;
}
else {
out[0] = reg;
out[1] = (uint8_t) (value >> 8);
out[2] = (uint8_t) value;
}
err = i2c_bus_transfer(dev->base.bus, &msgs[0], RTEMS_ARRAY_SIZE(msgs));
if (err == 0)
dev->pointer = reg;
else
dev->pointer = -1;
return err;
}
static int
ti_tmp112_reg_read(ti_tmp112* dev, int reg, uint16_t* value)
{
uint8_t in[2] = { 0, 0 };
int err;
if (dev->pointer == reg) {
i2c_msg msgs[1] = {
{
.addr = dev->base.address,
.flags = I2C_M_RD,
.len = (uint16_t) sizeof(in),
.buf = &in[0]
}
};
err = i2c_bus_transfer(dev->base.bus, &msgs[0], RTEMS_ARRAY_SIZE(msgs));
}
else {
uint8_t out[1] = { (uint8_t) reg };
i2c_msg msgs[2] = {
{
.addr = dev->base.address,
.flags = 0,
.len = (uint16_t) sizeof(out),
.buf = &out[0]
}, {
.addr = dev->base.address,
.flags = I2C_M_RD,
.len = (uint16_t) sizeof(in),
.buf = &in[0]
}
};
err = i2c_bus_transfer(dev->base.bus, &msgs[0], RTEMS_ARRAY_SIZE(msgs));
if (err == 0)
dev->pointer = reg;
else
dev->pointer = -1;
}
*value = (((uint16_t) in[0]) << 8) | in[1];
return err;
}
static int
ti_tmp112_set_config(ti_tmp112* dev, uint16_t value)
{
int err;
dev->config_shadow = value;
err = ti_tmp112_reg_write(dev, TMP_CONFIG, dev->config_shadow);
return err;
}
static int
ti_tmp112_get_temp(ti_tmp112* dev, int* temp, bool raw)
{
uint16_t value = 0;
int err;
*temp = 0;
if ((dev->config_shadow & CFG_SHUTDOWN) == CFG_SHUTDOWN) {
i2c_bus_obtain(dev->base.bus);
err = ti_tmp112_reg_write(dev,
TMP_CONFIG,
dev->config_shadow | CFG_ONE_SHOT);
if (err == 0) {
uint16_t config = 0;
while (err == 0 && (config & CFG_ONE_SHOT) == 0)
err = ti_tmp112_reg_read(dev, TMP_CONFIG, &config);
err = ti_tmp112_reg_read(dev, TMP_TEMPERATURE, &value);
}
i2c_bus_release(dev->base.bus);
}
else {
err = ti_tmp112_reg_read(dev, TMP_TEMPERATURE, &value);
}
if (err == 0) {
if (raw) {
*temp = (int) value;
}
else {
int bits = 12;
uint32_t u;
if ((dev->config_shadow & CFG_EXTENDED_MODE) != 0)
bits = 13;
u = value >> ((sizeof(value) * 8) - bits);
*temp = (int) (u & ((1 << bits) - 1));
if ((u & (1 << (bits - 1))) != 0)
*temp |= ~((1 << bits) - 1);
*temp = *temp * 625;
}
}
return err;
}
static int
ti_tmp112_ioctl(i2c_dev* iic_dev, ioctl_command_t command, void* arg)
{
ti_tmp112* dev = (ti_tmp112*) iic_dev;
uint16_t v16;
int vint;
int err;
switch (command) {
case TI_TMP112_GET_TEMP:
vint = 0;
err = ti_tmp112_get_temp(dev, &vint, false);
if (err == 0)
*((int*) arg) = vint;
break;
case TI_TMP112_GET_TEMP_RAW:
vint = 0;
err = ti_tmp112_get_temp(dev, &vint, true);
if (err == 0)
*((uint16_t*) arg) = (uint16_t) vint;
break;
case TI_TMP112_SET_CONFIG:
v16 = (uint16_t)(uintptr_t) arg;
err = ti_tmp112_set_config(dev, v16);
break;
case TI_TMP112_SET_LOW_TEMP:
v16 = (uint16_t)(uintptr_t) arg;
err = ti_tmp112_reg_write(dev, TMP_LOW_TEMP, v16);
break;
case TI_TMP112_SET_HIGH_TEMP:
v16 = (uint16_t)(uintptr_t) arg;
err = ti_tmp112_reg_write(dev, TMP_HIGH_TEMP, v16);
break;
default:
err = -ENOTTY;
break;
}
return err;
}
int
i2c_dev_register_ti_tmp112(const char* bus_path,
const char* dev_path,
uint16_t address)
{
ti_tmp112* dev;
dev = (ti_tmp112*)
i2c_dev_alloc_and_init(sizeof(*dev), bus_path, address);
if (dev == NULL) {
return -1;
}
dev->base.ioctl = ti_tmp112_ioctl;
dev->pointer = -1;
dev->config_shadow = 0x60a0;
return i2c_dev_register(&dev->base, dev_path);
}