| Message ID | 20210121191431.12057-2-dmurphy@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] iio:adc:ti-ads124s08: Fix start stop conversion command | expand |
On Thu, 21 Jan 2021 13:14:31 -0600 Dan Murphy <dmurphy@ti.com> wrote: > Fix the spi_transfer array in the reading of the data from the ADC. > > Fixes: ("e717f8c6dfec iio: adc: Add the TI ads124s08 ADC code") > Signed-off-by: Dan Murphy <dmurphy@ti.com> I'm not really following the changes below.. > --- > drivers/iio/adc/ti-ads124s08.c | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) > > diff --git a/drivers/iio/adc/ti-ads124s08.c b/drivers/iio/adc/ti-ads124s08.c > index f05d4e0e1c9d..023d81c7e8da 100644 > --- a/drivers/iio/adc/ti-ads124s08.c > +++ b/drivers/iio/adc/ti-ads124s08.c > @@ -201,12 +201,10 @@ static int ads124s_read(struct iio_dev *indio_dev, unsigned int chan) > struct spi_transfer t[] = { > { > .tx_buf = &priv->data[0], > - .len = 4, > - .cs_change = 1, We should still need to provide a length for this transfer. > }, { > - .tx_buf = &priv->data[1], > .rx_buf = &priv->data[1], > .len = 4, > + .cs_change = 1, That's unusual... cs_change being set on the last transfer means the opposite of what it does for earlier transfers. https://elixir.bootlin.com/linux/latest/source/include/linux/spi/spi.h#L905 Or is the intent here to provide a performance hint that the device doesn't care if the cs line goes inactive before stating a new set of transfers? If so add a comment to say that perhaps. > }, > }; >
Jonathan On 1/24/21 9:12 AM, Jonathan Cameron wrote: > On Thu, 21 Jan 2021 13:14:31 -0600 > Dan Murphy <dmurphy@ti.com> wrote: > >> Fix the spi_transfer array in the reading of the data from the ADC. >> >> Fixes: ("e717f8c6dfec iio: adc: Add the TI ads124s08 ADC code") >> Signed-off-by: Dan Murphy <dmurphy@ti.com> > I'm not really following the changes below.. I will have to dig into it deeper our HW team reported this. Patch 1/2 is relevant and is not dependent on this patch Dan
diff --git a/drivers/iio/adc/ti-ads124s08.c b/drivers/iio/adc/ti-ads124s08.c index f05d4e0e1c9d..023d81c7e8da 100644 --- a/drivers/iio/adc/ti-ads124s08.c +++ b/drivers/iio/adc/ti-ads124s08.c @@ -201,12 +201,10 @@ static int ads124s_read(struct iio_dev *indio_dev, unsigned int chan) struct spi_transfer t[] = { { .tx_buf = &priv->data[0], - .len = 4, - .cs_change = 1, }, { - .tx_buf = &priv->data[1], .rx_buf = &priv->data[1], .len = 4, + .cs_change = 1, }, };
Fix the spi_transfer array in the reading of the data from the ADC. Fixes: ("e717f8c6dfec iio: adc: Add the TI ads124s08 ADC code") Signed-off-by: Dan Murphy <dmurphy@ti.com> --- drivers/iio/adc/ti-ads124s08.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)