Add support the VZ89TE variant which removes the voc_short channel,
and has CRC check for data transactions.
Signed-off-by: Matt Ranostay <mranostay@xxxxxxxxx>
---
drivers/iio/chemical/vz89x.c | 149 +++++++++++++++++++++++++++++++++++--------
1 file changed, 123 insertions(+), 26 deletions(-)
diff --git a/drivers/iio/chemical/vz89x.c b/drivers/iio/chemical/vz89x.c
index f498228e044d..0347761ebdba 100644
--- a/drivers/iio/chemical/vz89x.c
+++ b/drivers/iio/chemical/vz89x.c
@@ -19,20 +19,33 @@
#include <linux/mutex.h>
#include <linux/init.h>
#include <linux/i2c.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#define VZ89X_REG_MEASUREMENT 0x09
+#define VZ89TE_REG_MEASUREMENT 0x0c
+
+#define VZ89X_REG_WRITE_SIZE 3
+#define VZ89TE_REG_WRITE_SIZE 6
+
#define VZ89X_REG_MEASUREMENT_SIZE 6
+#define VZ89TE_REG_MEASUREMENT_SIZE 7
#define VZ89X_VOC_CO2_IDX 0
#define VZ89X_VOC_SHORT_IDX 1
#define VZ89X_VOC_TVOC_IDX 2
#define VZ89X_VOC_RESISTANCE_IDX 3
+#define VZ89TE_VOC_TVOC_IDX 0
+#define VZ89TE_VOC_CO2_IDX 1
+#define VZ89TE_VOC_RESISTANCE_IDX 2
+
enum {
VZ89X,
+ VZ89TE,
};
struct vz89x_data {
@@ -79,6 +92,40 @@ static const struct iio_chan_spec vz89x_channels[] = {
.info_mask_separate =
BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
.address = VZ89X_VOC_RESISTANCE_IDX,
+ .scan_index = -1,
+ .scan_type = {
+ .endianness = IIO_LE,
+ },
+ },
+};
+
+static const struct iio_chan_spec vz89te_channels[] = {
+ {
+ .type = IIO_CONCENTRATION,
+ .channel2 = IIO_MOD_VOC,
+ .modified = 1,
+ .info_mask_separate =
+ BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_RAW),
+ .address = VZ89TE_VOC_TVOC_IDX,
+ },
+
+ {
+ .type = IIO_CONCENTRATION,
+ .channel2 = IIO_MOD_CO2,
+ .modified = 1,
+ .info_mask_separate =
+ BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_RAW),
+ .address = VZ89TE_VOC_CO2_IDX,
+ },
+ {
+ .type = IIO_RESISTANCE,
+ .info_mask_separate =
+ BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
+ .address = VZ89TE_VOC_RESISTANCE_IDX,
+ .scan_index = -1,
+ .scan_type = {
+ .endianness = IIO_BE,
+ },
},
};
@@ -110,12 +157,27 @@ static int vz89x_measurement_is_valid(struct vz89x_data *data)
return !!(data->buffer[data->read_size - 1] > 0);
}
+/* VZ89TE device has a modified CRC-8 two complement check */
+static int vz89te_measurement_is_valid(struct vz89x_data *data)
+{
+ u8 crc = 0;
+ int i, sum = 0;
+
+ for (i = 0; i < (data->read_size - 1); i++) {
+ sum = crc + data->buffer[i];
+ crc = sum;
+ crc += sum / 256;
+ }
+
+ return !((0xff - crc) == data->buffer[data->read_size - 1]);
+}
+
static int vz89x_i2c_xfer(struct vz89x_data *data, u8 cmd)
{
struct i2c_client *client = data->client;
struct i2c_msg msg[2];
int ret;
- u8 buf[3] = { cmd, 0, 0};
+ u8 buf[6] = { cmd, 0, 0, 0, 0, 0xf3};
msg[0].addr = client->addr;
msg[0].flags = client->flags;
@@ -173,11 +235,24 @@ static int vz89x_get_measurement(struct vz89x_data *data)
return 0;
}
-static int vz89x_get_resistance_reading(struct vz89x_data *data)
+static int vz89x_get_resistance_reading(struct vz89x_data *data,
+ struct iio_chan_spec const *chan,
+ int *val)
{
- u8 *buf = &data->buffer[VZ89X_VOC_RESISTANCE_IDX];
+ u32 tmp = *((u32 *) ((u8 *) &data->buffer[chan->address]));
+
+ switch (chan->scan_type.endianness) {
+ case IIO_LE:
+ *val = le32_to_cpu(tmp) & GENMASK(23, 0);
+ break;
+ case IIO_BE:
+ *val = be32_to_cpu(tmp) >> 8;
+ break;
+ default:
+ return -EINVAL;
+ }
- return buf[0] | (buf[1] << 8);
+ return 0;
}
static int vz89x_read_raw(struct iio_dev *indio_dev,
@@ -196,15 +271,15 @@ static int vz89x_read_raw(struct iio_dev *indio_dev,
if (ret)
return ret;
- switch (chan->address) {
- case VZ89X_VOC_CO2_IDX:
- case VZ89X_VOC_SHORT_IDX:
- case VZ89X_VOC_TVOC_IDX:
+ switch (chan->type) {
+ case IIO_CONCENTRATION:
*val = data->buffer[chan->address];
return IIO_VAL_INT;
- case VZ89X_VOC_RESISTANCE_IDX:
- *val = vz89x_get_resistance_reading(data);
- return IIO_VAL_INT;
+ case IIO_RESISTANCE:
+ ret = vz89x_get_resistance_reading(data, chan, val);
+ if (!ret)
+ return IIO_VAL_INT;
+ break;
default:
return -EINVAL;
}
@@ -219,12 +294,12 @@ static int vz89x_read_raw(struct iio_dev *indio_dev,
}
break;
case IIO_CHAN_INFO_OFFSET:
- switch (chan->address) {
- case VZ89X_VOC_CO2_IDX:
+ switch (chan->channel2) {
+ case IIO_MOD_CO2:
*val = 44;
*val2 = 250000;
return IIO_VAL_INT_PLUS_MICRO;
- case VZ89X_VOC_TVOC_IDX:
+ case IIO_MOD_VOC:
*val = -13;
return IIO_VAL_INT;
default:
@@ -241,11 +316,20 @@ static const struct iio_info vz89x_info = {
.driver_module = THIS_MODULE,
};
+static const struct of_device_id vz89x_dt_ids[] = {
+ { .compatible = "sgx,vz89x", .data = (void *) VZ89X },
+ { .compatible = "sgx,vz89te", .data = (void *) VZ89TE },
+ { }
+};
+MODULE_DEVICE_TABLE(of, vz89x_dt_ids);
+
static int vz89x_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct iio_dev *indio_dev;
struct vz89x_data *data;
+ const struct of_device_id *of_id;
+ int chip_id;
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
if (!indio_dev)
@@ -260,13 +344,15 @@ static int vz89x_probe(struct i2c_client *client,
else
return -EOPNOTSUPP;
+ of_id = of_match_device(vz89x_dt_ids, &client->dev);
+ if (!of_id)
+ chip_id = id->driver_data;
+ else
+ chip_id = (unsigned long)of_id->data;
+
i2c_set_clientdata(client, indio_dev);
data->client = client;
data->last_update = jiffies - HZ;
- data->cmd = VZ89X_REG_MEASUREMENT;
- data->write_size = 3;
- data->read_size = VZ89X_REG_MEASUREMENT_SIZE;
- data->valid = &vz89x_measurement_is_valid;
mutex_init(&data->lock);
indio_dev->dev.parent = &client->dev;
@@ -274,24 +360,35 @@ static int vz89x_probe(struct i2c_client *client,
indio_dev->name = dev_name(&client->dev);
indio_dev->modes = INDIO_DIRECT_MODE;
- indio_dev->channels = vz89x_channels;
- indio_dev->num_channels = ARRAY_SIZE(vz89x_channels);
+ switch (chip_id) {
+ case VZ89X:
+ indio_dev->channels = vz89x_channels;
+ indio_dev->num_channels = ARRAY_SIZE(vz89x_channels);
+ data->cmd = VZ89X_REG_MEASUREMENT;
+ data->write_size = VZ89X_REG_WRITE_SIZE;
+ data->read_size = VZ89X_REG_MEASUREMENT_SIZE;
+ data->valid = &vz89x_measurement_is_valid;
+ break;
+ case VZ89TE:
+ indio_dev->channels = vz89te_channels;
+ indio_dev->num_channels = ARRAY_SIZE(vz89te_channels);
+ data->cmd = VZ89TE_REG_MEASUREMENT;
+ data->write_size = VZ89TE_REG_WRITE_SIZE;
+ data->read_size = VZ89TE_REG_MEASUREMENT_SIZE;
+ data->valid = &vz89te_measurement_is_valid;
+ break;
+ }
return devm_iio_device_register(&client->dev, indio_dev);
}
static const struct i2c_device_id vz89x_id[] = {
{ "vz89x", VZ89X },
+ { "vz89te", VZ89TE },
{ }
};
MODULE_DEVICE_TABLE(i2c, vz89x_id);
-static const struct of_device_id vz89x_dt_ids[] = {
- { .compatible = "sgx,vz89x", .data = (void *) VZ89X },
- { }
-};
-MODULE_DEVICE_TABLE(of, vz89x_dt_ids);
-
static struct i2c_driver vz89x_driver = {
.driver = {
.name = "vz89x",
--
2.7.4
--
To unsubscribe from this list: send the line "unsubscribe linux-iio" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
