From ac5acb9530be89163bf0155004abea10bcee7516 Mon Sep 17 00:00:00 2001
From: "Peter A. Bigot" <pab@pabigot.com>
Date: Fri, 23 Nov 2018 07:16:36 -0600
Subject: [PATCH] drivers: sensor: ccs811: provide API to fetch configuration
 and versions

The application may want to know the configured mode without inspecting
Kconfig macros; this is important for proper management of BASELINE
which is mode-dependent.

It also may need to know the version of the hardware and firmware, as
the behavior of application firmware 2.0 is significantly better than
version 1.1.

Signed-off-by: Peter A. Bigot <pab@pabigot.com>
---
 drivers/sensor/ccs811/ccs811.c  | 45 +++++++++++++++++++++++++++++++++
 drivers/sensor/ccs811/ccs811.h  |  5 ++--
 include/drivers/sensor/ccs811.h | 26 +++++++++++++++++++
 3 files changed, 74 insertions(+), 2 deletions(-)

diff --git a/drivers/sensor/ccs811/ccs811.c b/drivers/sensor/ccs811/ccs811.c
index 8e4d1e11dbb..29caa9fc233 100644
--- a/drivers/sensor/ccs811/ccs811.c
+++ b/drivers/sensor/ccs811/ccs811.c
@@ -77,6 +77,51 @@ const struct ccs811_result_type *ccs811_result(struct device *dev)
 	return &drv_data->result;
 }
 
+int ccs811_configver_fetch(struct device *dev,
+			   struct ccs811_configver_type *ptr)
+{
+	struct ccs811_data *drv_data = dev->driver_data;
+	u8_t cmd;
+	int rc;
+
+	if (!ptr) {
+		return -EINVAL;
+	}
+
+	set_wake(drv_data, true);
+	cmd = CCS811_REG_HW_VERSION;
+	rc = i2c_write_read(drv_data->i2c, DT_INST_0_AMS_CCS811_BASE_ADDRESS,
+			    &cmd, sizeof(cmd),
+			    &ptr->hw_version, sizeof(ptr->hw_version));
+	if (rc == 0) {
+		cmd = CCS811_REG_FW_BOOT_VERSION;
+		rc = i2c_write_read(drv_data->i2c, DT_INST_0_AMS_CCS811_BASE_ADDRESS,
+				    &cmd, sizeof(cmd),
+				    (u8_t *)&ptr->fw_boot_version,
+				    sizeof(ptr->fw_boot_version));
+		ptr->fw_boot_version = sys_be16_to_cpu(ptr->fw_boot_version);
+	}
+
+	if (rc == 0) {
+		cmd = CCS811_REG_FW_APP_VERSION;
+		rc = i2c_write_read(drv_data->i2c, DT_INST_0_AMS_CCS811_BASE_ADDRESS,
+				    &cmd, sizeof(cmd),
+				    (u8_t *)&ptr->fw_app_version,
+				    sizeof(ptr->fw_app_version));
+		ptr->fw_app_version = sys_be16_to_cpu(ptr->fw_app_version);
+	}
+	if (rc == 0) {
+		LOG_INF("HW %x FW %x APP %x",
+			ptr->hw_version, ptr->fw_boot_version,
+			ptr->fw_app_version);
+	}
+
+	set_wake(drv_data, false);
+	ptr->mode = drv_data->mode & CCS811_MODE_MSK;
+
+	return rc;
+}
+
 int ccs811_baseline_fetch(struct device *dev)
 {
 	const u8_t cmd = CCS811_REG_BASELINE;
diff --git a/drivers/sensor/ccs811/ccs811.h b/drivers/sensor/ccs811/ccs811.h
index c8618d11dc4..bb58b677f5a 100644
--- a/drivers/sensor/ccs811/ccs811.h
+++ b/drivers/sensor/ccs811/ccs811.h
@@ -23,12 +23,13 @@
 #define CCS811_REG_BASELINE             0x11
 #define CCS811_REG_HW_ID                0x20
 #define CCS811_REG_HW_VERSION           0x21
-#define CCS811_REG_HW_VERSION_MASK      0xF0
+#define CCS811_REG_FW_BOOT_VERSION      0x23
+#define CCS811_REG_FW_APP_VERSION       0x24
 #define CCS811_REG_ERROR_ID             0xE0
 #define CCS811_REG_APP_START            0xF4
 
 #define CCS881_HW_ID                    0x81
-#define CCS811_HW_VERSION               0x10
+#define CCS811_HW_VERSION_MSK           0xF0
 
 /* Measurement modes */
 #define CCS811_MODE_RAW_DATA            0x40
diff --git a/include/drivers/sensor/ccs811.h b/include/drivers/sensor/ccs811.h
index c51d8e52866..821880e0565 100644
--- a/include/drivers/sensor/ccs811.h
+++ b/include/drivers/sensor/ccs811.h
@@ -42,6 +42,7 @@ extern "C" {
 #define CCS811_MODE_IAQ_10SEC           0x20
 #define CCS811_MODE_IAQ_60SEC           0x30
 #define CCS811_MODE_IAQ_250MSEC         0x40
+#define CCS811_MODE_MSK                 0x70
 
 /** @brief Information collected from the sensor on each fetch. */
 struct ccs811_result_type {
@@ -81,6 +82,31 @@ struct ccs811_result_type {
  */
 const struct ccs811_result_type *ccs811_result(struct device *dev);
 
+/**
+ * @brief Get information about static CCS811 state.
+ *
+ * This includes the configured operating mode as well as hardware and
+ * firmware versions.
+ */
+struct ccs811_configver_type {
+	u16_t fw_boot_version;
+	u16_t fw_app_version;
+	u8_t hw_version;
+	u8_t mode;
+};
+
+/**
+ * @brief Fetch operating mode and version information.
+ *
+ * @param dev Pointer to the sensor device
+ *
+ * @param ptr Pointer to where the returned information should be stored
+ *
+ * @return 0 on success, or a negative errno code on failure.
+ */
+int ccs811_configver_fetch(struct device *dev,
+			   struct ccs811_configver_type *ptr);
+
 /**
  * @brief Fetch the current value of the BASELINE register.
  *