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Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <1548440422-27943-1-git-send-email-justinpopo6@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org On 1/25/19 10:20 AM, justinpopo6@gmail.com wrote: > From: Justin Chen > > To read a channel we require 3 cycles to send, process, and receive > the data. The transfer buffer for the third transaction is left blank. > This leaves it up to the SPI driver to decide what to do. > > In one particular case, if the tx buffer is not set the spi driver > sets it to 0xff. This puts the ADC in a alarm programming state, > therefore the following read to a channel becomes erroneous. > > Instead of leaving us to the mercy of the SPI driver, we send the > ADC cmd on the third transaction to prevent inconsistent behavior. > > Fixes: 902c4b2446d4 ("iio: adc: New driver for TI ADS7950 chips") > Signed-off-by: Justin Chen Reviewed-by: Florian Fainelli Thanks! -- Florian