Soundwire xl turnaround signaling

An apparatus comprising:

• a physical interface coupled to a two-wire link and configured to transmit and receive differentially-encoded data over the two-wire link;
• and
• a processor or controller configured to:
• transmit first data to a device through the physical interface during a first time period;
• receive second data from the device through the physical interface during a second time period that follows a link turnaround period;
• and
• cause the physical interface to drive the two-wire link to a common signaling state during a third time period that includes at least a portion of the link turnaround period,
• wherein the two-wire link is driven by the device during at least a portion of the third time period.

An apparatus, comprising:

• a two-wire serial link;
• a master device coupled to the two-wire serial link;
• and
• a slave device coupled to the two-wire serial link,
• wherein the master device is configured to:
• transmit first differentially-encoded data to the slave device over the two-wire serial link during a first time period;
• disable differential line drivers of the master device during a second time period;
• and
• drive the two-wire serial link to a common signaling state during a third time period that includes at least a portion of a link turnaround period between the first time period and the second time period, and
• wherein the slave device is configured to:
• transmit second differentially-encoded data to the master device over the two-wire serial link during the second time period;
• drive the two-wire serial link to the common signaling state during a fourth time period that includes at least a portion of the link turnaround period;
• and
• disable differential line drivers of the slave device during the first time period.

An apparatus comprising:

• means for transmitting from a first device, first differentially-encoded data to a second device over a two-wire serial link during a first time period;
• means for receiving at the first device, second differentially-encoded data from the second device over the two-wire serial link during a second time period;
• and
• means for driving the two-wire serial link to a common signaling state for a third time period that includes at least a portion of a link turnaround period that separates the first time period and the second time period,
• wherein the two-wire serial link is driven to the common signaling state by the second device for at least a portion of the third time period.