temp_sensor: Add (basic) support for TI TMP468 Temperature Sensor

Add (basic) support for TI TMP468 a 8 Remote + 1 Local channel
temperature sensor.

BUG=none
BRANCH=master
TEST=Hook up EVM to I2C port of a STM32F072, read temperatures

Change-Id: I6d6644825af04391841847c060f8ffaeff620094
Signed-off-by: Moritz Fischer <moritz.fischer@ettus.com>
Reviewed-on: https://chromium-review.googlesource.com/1213554
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Reviewed-by: Randall Spangler <rspangler@chromium.org>

4 files changed, 228 insertions, 1 deletions

diff --git a/driver/build.mk b/driver/build.mk
index 50b478ef0d..2529aa2478 100644
--- a/driver/build.mk
+++ b/driver/build.mk
@@ -83,6 +83,7 @@ driver-$(CONFIG_REGULATOR_IR357X)+=regulator_ir357x.o
 driver-$(CONFIG_TEMP_SENSOR_ADT7481)+=temp_sensor/adt7481.o
 driver-$(CONFIG_TEMP_SENSOR_BD99992GW)+=temp_sensor/bd99992gw.o
 driver-$(CONFIG_TEMP_SENSOR_EC_ADC)+=temp_sensor/ec_adc.o
+driver-$(CONFIG_TEMP_SENSOR_F75303)+=temp_sensor/f75303.o
 driver-$(CONFIG_TEMP_SENSOR_G781)+=temp_sensor/g78x.o
 driver-$(CONFIG_TEMP_SENSOR_G782)+=temp_sensor/g78x.o
 driver-$(CONFIG_TEMP_SENSOR_SB_TSI)+=temp_sensor/sb_tsi.o
@@ -90,7 +91,7 @@ driver-$(CONFIG_TEMP_SENSOR_TMP006)+=temp_sensor/tmp006.o
 driver-$(CONFIG_TEMP_SENSOR_TMP112)+=temp_sensor/tmp112.o
 driver-$(CONFIG_TEMP_SENSOR_TMP411)+=temp_sensor/tmp411.o
 driver-$(CONFIG_TEMP_SENSOR_TMP432)+=temp_sensor/tmp432.o
-driver-$(CONFIG_TEMP_SENSOR_F75303)+=temp_sensor/f75303.o
+driver-$(CONFIG_TEMP_SENSOR_TMP468)+=temp_sensor/tmp468.o
 
 # Touchpads
 driver-$(CONFIG_TOUCHPAD_ELAN)+=touchpad_elan.o
diff --git a/driver/temp_sensor/tmp468.c b/driver/temp_sensor/tmp468.c
new file mode 100644
index 0000000000..e1d34079f2
--- /dev/null
+++ b/driver/temp_sensor/tmp468.c
@@ -0,0 +1,99 @@
+/* Copyright (c) 2018 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.
+ */
+
+/* TMP468 temperature sensor module for Chrome EC */
+
+#include "common.h"
+#include "console.h"
+#include "tmp432.h"
+#include "gpio.h"
+#include "i2c.h"
+#include "hooks.h"
+#include "util.h"
+
+#include "tmp468.h"
+
+
+static int fake_temp[TMP468_CHANNEL_COUNT] = {-1, -1, -1, -1, -1, -1, -1 , -1, -1};
+static int temp_val[TMP468_CHANNEL_COUNT]  = {0, 0, 0, 0, 0, 0, 0 , 0, 0};
+static uint8_t is_sensor_shutdown;
+
+static int has_power(void)
+{
+	return !is_sensor_shutdown;
+}
+
+static int raw_read16(const int offset, int *data_ptr)
+{
+	return i2c_read16(I2C_PORT_THERMAL, TMP468_I2C_ADDR, offset, data_ptr);
+}
+
+static int raw_write16(const int offset, int data_ptr)
+{
+	return i2c_write16(I2C_PORT_THERMAL, TMP468_I2C_ADDR, offset, data_ptr);
+}
+
+static int tmp468_shutdown(uint8_t want_shutdown)
+{
+	int ret, value;
+
+	if (want_shutdown == is_sensor_shutdown)
+		return EC_SUCCESS;
+
+	ret = raw_read16(TMP468_CONFIGURATION, &value);
+	if (ret < 0) {
+		ccprintf("ERROR: Temp sensor I2C read16 error.\n");
+		return ret;
+	}
+
+	if (want_shutdown)
+		value |= TMP468_SHUTDOWN;
+	else
+		value &= ~TMP468_SHUTDOWN;
+
+	ret = raw_write16(TMP468_CONFIGURATION, value);
+	if (ret == EC_SUCCESS)
+		is_sensor_shutdown = want_shutdown;
+
+	return EC_SUCCESS;
+}
+
+int tmp468_get_val(int idx, int *temp_ptr)
+{
+	if(!has_power())
+		return EC_ERROR_NOT_POWERED;
+
+	if (idx < TMP468_CHANNEL_COUNT) {
+		*temp_ptr = C_TO_K(temp_val[idx]);
+		return EC_SUCCESS;
+	}
+
+	return EC_ERROR_INVAL;
+}
+
+static void temp_sensor_poll(void)
+{
+	int i, ret;
+
+	if (!has_power())
+		return;
+
+	for (i = 0; i < TMP468_CHANNEL_COUNT; i++)
+		if (fake_temp[i] != -1) {
+			temp_val[i] = fake_temp[i];
+		} else {
+			ret = raw_read16(TMP468_LOCAL + i, &temp_val[i]);
+			if (ret < 0)
+				return;
+			temp_val[i] >>= TMP468_SHIFT1;
+		}
+}
+DECLARE_HOOK(HOOK_SECOND, temp_sensor_poll, HOOK_PRIO_TEMP_SENSOR);
+
+int tmp468_set_power(enum tmp468_power_state power_on)
+{
+	uint8_t shutdown = (power_on == TMP468_POWER_OFF) ? 1 : 0;
+	return tmp468_shutdown(shutdown);
+}
diff --git a/driver/temp_sensor/tmp468.h b/driver/temp_sensor/tmp468.h
new file mode 100644
index 0000000000..ec528d0dcc
--- /dev/null
+++ b/driver/temp_sensor/tmp468.h
@@ -0,0 +1,126 @@
+/* Copyright (c) 2018 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.
+ */
+
+/* TMP468 temperature sensor module for Chrome EC */
+
+#ifndef __CROS_EC_TMP468_H
+#define __CROS_EC_TMP468_H
+
+#define TMP468_I2C_ADDR (0x90 | I2C_FLAG_BIG_ENDIAN)
+#define TMP468_SHIFT1 7
+
+#define TMP468_LOCAL			0x00
+#define TMP468_REMOTE1			0x01
+#define TMP468_REMOTE2			0x02
+#define TMP468_REMOTE3			0x03
+#define TMP468_REMOTE4			0x04
+#define TMP468_REMOTE5			0x05
+#define TMP468_REMOTE6			0x06
+#define TMP468_REMOTE7			0x07
+#define TMP468_REMOTE8			0x08
+
+#define TMP468_SRST			0x20
+#define TMP468_THERM			0x21
+#define TMP468_THERM2			0x22
+#define TMP468_ROPEN			0x23
+
+#define TMP468_CONFIGURATION		0x30
+#define TMP468_THERM_HYST		0x38
+
+#define TMP468_LOCAL_LOW_LIMIT		0x39
+#define TMP468_LOCAL_HIGH_LIMT		0x3a
+
+#define TMP468_REMOTE1_OFFSET		0x40
+#define TMP468_REMOTE1_NFACTOR		0x41
+#define TMP468_REMOTE1_LOW_LIMIT	0x41
+#define TMP468_REMOTE1_HIGH_LIMIT	0x42
+
+#define TMP468_REMOTE2_OFFSET		0x48
+#define TMP468_REMOTE2_NFACTOR		0x49
+#define TMP468_REMOTE2_LOW_LIMIT	0x4a
+#define TMP468_REMOTE2_HIGH_LIMIT	0x4b
+
+#define TMP468_REMOTE3_OFFSET		0x50
+#define TMP468_REMOTE3_NFACTOR		0x51
+#define TMP468_REMOTE3_LOW_LIMIT	0x52
+#define TMP468_REMOTE3_HIGH_LIMIT	0x53
+
+#define TMP468_REMOTE4_OFFSET		0x58
+#define TMP468_REMOTE4_NFACTOR		0x59
+#define TMP468_REMOTE4_LOW_LIMIT	0x59
+#define TMP468_REMOTE4_HIGH_LIMIT	0x5a
+
+#define TMP468_REMOTE5_OFFSET		0x60
+#define TMP468_REMOTE5_NFACTOR		0x61
+#define TMP468_REMOTE5_LOW_LIMIT	0x62
+#define TMP468_REMOTE5_HIGH_LIMIT	0x63
+
+#define TMP468_REMOTE6_OFFSET		0x68
+#define TMP468_REMOTE6_NFACTOR		0x69
+#define TMP468_REMOTE6_LOW_LIMIT	0x6a
+#define TMP468_REMOTE6_HIGH_LIMIT	0x6b
+
+#define TMP468_REMOTE7_OFFSET		0x70
+#define TMP468_REMOTE7_NFACTOR		0x71
+#define TMP468_REMOTE7_LOW_LIMIT	0x72
+#define TMP468_REMOTE7_HIGH_LIMIT	0x73
+
+#define TMP468_REMOTE8_OFFSET		0x78
+#define TMP468_REMOTE8_NFACTOR		0x79
+#define TMP468_REMOTE8_LOW_LIMIT	0x7a
+#define TMP468_REMOTE8_HIGH_LIMIT	0x7b
+
+#define TMP468_LOCK			0xc4
+
+#define TMP468_DEVICE_ID		0xfd
+#define TMP468_MANUFACTURER_ID		0xfe
+
+#define TMP468_SHUTDOWN			(1 << 5)
+
+enum tmp468_channel_id {
+	TMP468_CHANNEL_LOCAL,
+
+	TMP468_CHANNEL_REMOTE1,
+	TMP468_CHANNEL_REMOTE2,
+	TMP468_CHANNEL_REMOTE3,
+	TMP468_CHANNEL_REMOTE4,
+	TMP468_CHANNEL_REMOTE5,
+	TMP468_CHANNEL_REMOTE6,
+	TMP468_CHANNEL_REMOTE7,
+	TMP468_CHANNEL_REMOTE8,
+
+	TMP468_CHANNEL_COUNT
+};
+
+enum tmp468_power_state {
+	TMP468_POWER_OFF = 0,
+	TMP468_POWER_ON,
+
+	TMP468_POWER_COUNT
+};
+
+
+/**
+ * Get the last polled value of a sensor.
+ *
+ * @param idx		Index to read. Idx indicates whether to read die
+ *			temperature or external temperature.
+ * @param temp_ptr	Destination for temperature in K.
+ *
+ * @return EC_SUCCESS if successful, non-zero if error.
+ */
+int tmp468_get_val(int idx, int *temp_ptr);
+
+/**
+ * Power control function of tmp432 temperature sensor.
+ *
+ * @param power_on	TMP468_POWER_ON: turn tmp468 sensor on.
+ *			TMP468_POWER_OFF: shut tmp468 sensor down.
+ *
+ * @return EC_SUCCESS if successful, non-zero if error.
+ */
+int tmp468_set_power(enum tmp468_power_state power_on);
+
+#endif /* __CROS_EC_TMP468_H */
diff --git a/include/config.h b/include/config.h
index cecf256b62..21d58a0ec7 100644
--- a/include/config.h
+++ b/include/config.h
@@ -2867,6 +2867,7 @@
 #undef CONFIG_TEMP_SENSOR_TMP006	/* TI TMP006 sensor, on I2C bus */
 #undef CONFIG_TEMP_SENSOR_TMP411	/* TI TMP411 sensor, on I2C bus */
 #undef CONFIG_TEMP_SENSOR_TMP432	/* TI TMP432 sensor, on I2C bus */
+#undef CONFIG_TEMP_SENSOR_TMP468	/* TI TMP468 sensor, on I2C bus */
 #undef CONFIG_TEMP_SENSOR_F75303	/* Fintek  F75303 sensor, on I2C bus */
 
 /* Compile common code for thermistor support */