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 | 113 +++++++++++++++++++++++++++++++++++++------
1 file changed, 98 insertions(+), 15 deletions(-)
diff --git a/drivers/iio/chemical/vz89x.c b/drivers/iio/chemical/vz89x.c
index aa6ebc084e19..289d2919deea 100644
--- a/drivers/iio/chemical/vz89x.c
+++ b/drivers/iio/chemical/vz89x.c
@@ -34,8 +34,17 @@
#define VZ89X_VOC_TVOC_IDX 2
#define VZ89X_VOC_RESISTANCE_IDX 3
+#define VZ89TE_REG_MEASUREMENT 0x0c
+#define VZ89TE_REG_MEASUREMENT_RD_SIZE 7
+#define VZ89TE_REG_MEASUREMENT_WR_SIZE 6
+
+#define VZ89TE_VOC_TVOC_IDX 0
+#define VZ89TE_VOC_CO2_IDX 1
+#define VZ89TE_VOC_RESISTANCE_IDX 2
+
enum {
VZ89X,
+ VZ89TE,
};
struct vz89x_chip_data;
@@ -47,7 +56,7 @@ struct vz89x_data {
int (*xfer)(struct vz89x_data *data, u8 cmd);
unsigned long last_update;
- u8 buffer[VZ89X_REG_MEASUREMENT_RD_SIZE];
+ u8 buffer[VZ89TE_REG_MEASUREMENT_RD_SIZE];
};
struct vz89x_chip_data {
@@ -90,6 +99,40 @@ 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,
+ },
},
};
@@ -121,13 +164,28 @@ static bool vz89x_measurement_is_valid(struct vz89x_data *data)
return !!(data->buffer[data->chip->read_size - 1] > 0);
}
+/* VZ89TE device has a modified CRC-8 two complement check */
+static bool vz89te_measurement_is_valid(struct vz89x_data *data)
+{
+ u8 crc = 0;
+ int i, sum = 0;
+
+ for (i = 0; i < (data->chip->read_size - 1); i++) {
+ sum = crc + data->buffer[i];
+ crc = sum;
+ crc += sum / 256;
+ }
+
+ return !((0xff - crc) == data->buffer[data->chip->read_size - 1]);
+}
+
static int vz89x_i2c_xfer(struct vz89x_data *data, u8 cmd)
{
const struct vz89x_chip_data *chip = data->chip;
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;
@@ -186,11 +244,24 @@ 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];
+ u8 *tmp = (u8 *) &data->buffer[chan->address];
- return buf[0] | (buf[1] << 8);
+ switch (chan->scan_type.endianness) {
+ case IIO_LE:
+ *val = le32_to_cpup((__le32 *) tmp) & GENMASK(23, 0);
+ break;
+ case IIO_BE:
+ *val = be32_to_cpup((__be32 *) tmp) >> 8;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
}
static int vz89x_read_raw(struct iio_dev *indio_dev,
@@ -209,15 +280,15 @@ 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;
}
@@ -232,12 +303,12 @@ 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:
@@ -265,10 +336,21 @@ static const struct vz89x_chip_data vz89x_chips[] = {
.channels = vz89x_channels,
.num_channels = ARRAY_SIZE(vz89x_channels),
},
+ {
+ .valid = vz89te_measurement_is_valid,
+
+ .cmd = VZ89TE_REG_MEASUREMENT,
+ .read_size = VZ89TE_REG_MEASUREMENT_RD_SIZE,
+ .write_size = VZ89TE_REG_MEASUREMENT_WR_SIZE,
+
+ .channels = vz89te_channels,
+ .num_channels = ARRAY_SIZE(vz89te_channels),
+ },
};
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);
@@ -319,6 +401,7 @@ static int vz89x_probe(struct i2c_client *client,
static const struct i2c_device_id vz89x_id[] = {
{ "vz89x", VZ89X },
+ { "vz89te", VZ89TE },
{ }
};
MODULE_DEVICE_TABLE(i2c, vz89x_id);
--
2.7.4
--
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