diff options
author | Moritz Fischer <moritz.fischer@ettus.com> | 2016-12-06 09:25:33 -0800 |
---|---|---|
committer | chrome-bot <chrome-bot@chromium.org> | 2016-12-30 18:14:34 -0800 |
commit | 73d0b9ca9f57e2693e394e81d7d2ab27f348d613 (patch) | |
tree | dd264c879158814cc8ad6928cd7b65cfa6c51ccb /driver/temp_sensor | |
parent | bf3f8ca53fac14cafaa8e66f682f5542f71a97ca (diff) | |
download | chrome-ec-73d0b9ca9f57e2693e394e81d7d2ab27f348d613.tar.gz |
driver: temp_sensor: Add support for TI TMP112 sensor
Add support for the Texas Instruments TMP112 I2C temperature
sensor. The sensor provides a single temperature value.
BUG=none
BRANCH=none
TEST=Ran 'temp' console command over and over. Verified values with
digital thermometer.
Change-Id: Ida4c082309d245c3f7c6282ecea74ce5af746e43
Signed-off-by: Moritz Fischer <moritz.fischer@ettus.com>
Reviewed-on: https://chromium-review.googlesource.com/418488
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Diffstat (limited to 'driver/temp_sensor')
-rw-r--r-- | driver/temp_sensor/tmp112.c | 82 | ||||
-rw-r--r-- | driver/temp_sensor/tmp112.h | 29 |
2 files changed, 111 insertions, 0 deletions
diff --git a/driver/temp_sensor/tmp112.c b/driver/temp_sensor/tmp112.c new file mode 100644 index 0000000000..f567e2433c --- /dev/null +++ b/driver/temp_sensor/tmp112.c @@ -0,0 +1,82 @@ +/* Copyright (c) 2016 The Chromium OS Authors. All rights reserved. + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + */ + +/* TMP112 temperature sensor module for Chrome EC */ + +#include "common.h" +#include "console.h" +#include "tmp112.h" +#include "i2c.h" +#include "hooks.h" +#include "util.h" + +#define TMP112_RESOLUTION 12 +#define TMP112_SHIFT1 (16 - TMP112_RESOLUTION) +#define TMP112_SHIFT2 (TMP112_RESOLUTION - 8) + +static int temp_val_local; + +static int raw_read16(const int offset, int *data_ptr) +{ + return i2c_read16(I2C_PORT_THERMAL, TMP112_I2C_ADDR, offset, data_ptr); +} + +static int raw_write16(const int offset, int data) +{ + return i2c_write16(I2C_PORT_THERMAL, TMP112_I2C_ADDR, offset, data); +} + +static int get_temp(int *temp_ptr) +{ + int rv; + int temp_raw = 0; + + rv = raw_read16(TMP112_REG_TEMP, &temp_raw); + if (rv < 0) + return rv; + + *temp_ptr = (int)(int16_t)temp_raw; + return EC_SUCCESS; +} + +static inline int tmp112_reg_to_c(int16_t reg) +{ + int tmp; + + tmp = (((reg >> TMP112_SHIFT1) * 1000 ) >> TMP112_SHIFT2); + + return tmp / 1000; +} + +int tmp112_get_val(int idx, int *temp_ptr) +{ + *temp_ptr = temp_val_local; + return EC_SUCCESS; +} + +static void tmp112_poll(void) +{ + int temp_c = 0; + + if (get_temp(&temp_c) == EC_SUCCESS) + temp_val_local = C_TO_K(tmp112_reg_to_c(temp_c)); +} +DECLARE_HOOK(HOOK_SECOND, tmp112_poll, HOOK_PRIO_TEMP_SENSOR); + +static void tmp112_init(void) +{ + int tmp; + int set_mask, clr_mask; + + /* 12 bit mode */ + set_mask = (3 << 5); + + /* not oneshot mode */ + clr_mask = (1 << 7); + + raw_read16(TMP112_REG_CONF, &tmp); + raw_write16(TMP112_REG_CONF, (tmp & ~clr_mask) | set_mask); +} +DECLARE_HOOK(HOOK_INIT, tmp112_init, HOOK_PRIO_DEFAULT); diff --git a/driver/temp_sensor/tmp112.h b/driver/temp_sensor/tmp112.h new file mode 100644 index 0000000000..14ee56da0c --- /dev/null +++ b/driver/temp_sensor/tmp112.h @@ -0,0 +1,29 @@ +/* Copyright (c) 2016 The Chromium OS Authors. All rights reserved. + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + */ + +#ifndef __CROS_EC_TMP112_H +#define __CROS_EC_TMP112_H + +#include "i2c.h" + +#define TMP112_I2C_ADDR 0x90 | I2C_FLAG_BIG_ENDIAN + +#define TMP112_REG_TEMP 0x00 +#define TMP112_REG_CONF 0x01 +#define TMP112_REG_HYST 0x02 +#define TMP112_REG_MAX 0x03 + +/** + * Get the last polled value of a sensor. + * + * @param idx Index to read. (Ignored) + * + * @param temp_ptr Destination for temperature in K. + * + * @return EC_SUCCESS if successful, non-zero if error. + */ +int tmp112_get_val(int idx, int *temp_ptr); + +#endif /* __CROS_EC_TMP112_H */ |