Previously most drivers that used a i2c_check_functionality() check
condition required various error codes on failure. This patchset
converts to a standard of -EOPNOTSUPP
Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Add an optimized i2c transfer reading function, and fallback
to racey smbus transfers if client->adapter doesn't support this.
Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Chipset sometime updates in the middle of a reading causing it
to reset the data pointer, and causing invalid reading of previous data.
We can check for this invalid state by reading MSB of the resistance
reading that is always zero, and by also confirming the VOC_short isn't
zero.
Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Add support for VZ89X sensors VOC and CO2 reporting channels in
percentage which can be converted to part per million.
Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
