michaelh/zephyr
1
0
Fork 0
Code Releases Activity

drivers: sensor: ccs811: accommodate old firmware

Browse source 
The firmware version on the CCS811 on nrf52_pca20020 is generally
version 1.1, which does not set the data ready bit in the status
register.  Assume that a non-zero CO2 measurement on that version is
fresh for the purposes of determining the fetch status.

Signed-off-by: Peter Bigot <peter.bigot@nordicsemi.no>
This commit is contained in:
Peter Bigot 2019-12-13 09:36:16 -06:00 • committed by Maureen Helm
commit f041570188
2 changed files with 28 additions and 4 deletions
Download patch file Download diff file Expand all files Collapse all files

31
drivers/sensor/ccs811/ccs811.c
View file

@ -231,7 +231,7 @@ static int ccs811_sample_fetch(struct device *dev, enum sensor_channel chan)
struct ccs811_result_type *rp = &drv_data->result;
const u8_t cmd = CCS811_REG_ALG_RESULT_DATA;
int rc;
u16_t buf[4];
u16_t buf[4] = { 0 };
unsigned int status;
set_wake(drv_data, true);
@ -250,8 +250,16 @@ static int ccs811_sample_fetch(struct device *dev, enum sensor_channel chan)
rp->error = error_from_status(status);
rp->raw = sys_be16_to_cpu(buf[3]);
/* @todo APP FW 1.1 may not set DATA_READY. */
return (rp->status & CCS811_STATUS_DATA_READY) ? 0 : -EAGAIN;
/* APP FW 1.1 does not set DATA_READY, but it does set CO2 to
* zero while it's starting up. Assume a non-zero CO2 with
* old firmware is valid for the purposes of claiming the
* fetch was fresh.
*/
if ((drv_data->app_fw_ver <= 0x11)
&& (rp->co2 != 0)) {
status |= CCS811_STATUS_DATA_READY;
}
return (status & CCS811_STATUS_DATA_READY) ? 0 : -EAGAIN;
}
static int ccs811_channel_get(struct device *dev,
@ -421,8 +429,10 @@ static int ccs811_init(struct device *dev)
{
struct ccs811_data *drv_data = dev->driver_data;
int ret = 0;
u8_t hw_id;
int status;
u16_t fw_ver;
u8_t cmd;
u8_t hw_id;
*drv_data = (struct ccs811_data){ 0 };
drv_data->i2c = device_get_binding(DT_INST_0_AMS_CCS811_BUS_NAME);
@ -518,6 +528,19 @@ static int ccs811_init(struct device *dev)
goto out;
}
/* Check application firmware version (first byte) */
cmd = CCS811_REG_FW_APP_VERSION;
if (i2c_write_read(drv_data->i2c, DT_INST_0_AMS_CCS811_BASE_ADDRESS,
&cmd, sizeof(cmd),
&fw_ver, sizeof(fw_ver)) < 0) {
LOG_ERR("Failed to read App Firmware Version register");
ret = -EIO;
goto out;
}
fw_ver = sys_be16_to_cpu(fw_ver);
LOG_INF("App FW %04x", fw_ver);
drv_data->app_fw_ver = fw_ver >> 8U;
/* Configure measurement mode */
u8_t meas_mode = CCS811_MODE_IDLE;
#ifdef CONFIG_CCS811_DRIVE_MODE_1

1
drivers/sensor/ccs811/ccs811.h
View file

@ -79,6 +79,7 @@ struct ccs811_data {
#endif
struct ccs811_result_type result;
u8_t mode;
u8_t app_fw_ver;
};
#ifdef CONFIG_CCS811_TRIGGER