On Thu, Feb 27, 2025 at 06:30:04PM -0300, Jonathan Santos wrote: > On 02/13, Conor Dooley wrote: > > On Wed, Feb 12, 2025 at 03:16:16PM -0300, Jonathan Santos wrote: > > > In addition to GPIO synchronization, The AD7768-1 also supports > > > synchronization over SPI, which use is recommended when the GPIO > > > cannot provide a pulse synchronous with the base MCLK signal. It > > > consists of looping back the SYNC_OUT to the SYNC_IN pin and send > > > a command via SPI to trigger the synchronization. > > > > > > Add a new trigger-sources property to enable synchronization over SPI > > > and future multiple devices support. This property references the > > > main device (or trigger provider) responsible for generating the > > > SYNC_OUT pulse to drive the SYNC_IN of device. > > > > > > While at it, add description to the interrupts property. > > > > > > Signed-off-by: Jonathan Santos <Jonathan.Santos@xxxxxxxxxx> > > > --- > > > v3 Changes: > > > * Fixed dt-bindings errors. > > > * Trigger-source is set as an alternative to sync-in-gpios, so we > > > don't break the previous ABI. > > > * increased maxItems from trigger-sources to 2. > > > > > > v2 Changes: > > > * Patch added as replacement for adi,sync-in-spi patch. > > > * addressed the request for a description to interrupts property. > > > --- > > > .../bindings/iio/adc/adi,ad7768-1.yaml | 28 +++++++++++++++++-- > > > 1 file changed, 25 insertions(+), 3 deletions(-) > > > > > > diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7768-1.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7768-1.yaml > > > index 3ce59d4d065f..4bcc9e20fab9 100644 > > > --- a/Documentation/devicetree/bindings/iio/adc/adi,ad7768-1.yaml > > > +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7768-1.yaml > > > @@ -26,7 +26,19 @@ properties: > > > clock-names: > > > const: mclk > > > > > > + trigger-sources: > > > + description: > > > + Specifies the device responsible for driving the synchronization pin, > > > + as an alternative to adi,sync-in-gpios. If the own device node is > > > + referenced, The synchronization over SPI is enabled and the SYNC_OUT > > > + output will drive the SYNC_IN pin. > > > > Maybe a silly question, but why is self-reference needed here? > > sync-in-gpios is a required property at present, so why can't you > > operate under the assumption that neither the trigger-sources when > > neither are present? Is it because only one of the sources could be > > external and one internal, or there could be either one or two internal > > sources? Self-referencing properties always feel like a bit of a > > mistake. > > > We have one internal synchronization source and two external ones. > The internal is when /SYNC_OUT drives /SYNC_IN (in this case with self > referencing). The external sources include using a GPIO to drive the > /SYNC_IN (sync-in-gpio case) or using an external /SYNC_OUT, the last one > is described in the datasheet for multi-devices setup. > > The trigger-sources property is inteded to indicate wheter the /SYNC_OUT > signal originates from within the device or from another source. currently > we are only handling the internal case. We are not sure yet how to handle > the external sources. > > > > + maxItems: 2
