- /* Open drain pin should not be driven to 1 */
- if (value && test_bit(FLAG_OPEN_DRAIN, &desc->flags))
- return gpiod_direction_input(desc);
-
- /* Open source pin should not be driven to 0 */
- if (!value && test_bit(FLAG_OPEN_SOURCE, &desc->flags))
- return gpiod_direction_input(desc);
+ if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
+ /* First see if we can enable open drain in hardware */
+ if (gc->set_single_ended) {
+ ret = gc->set_single_ended(gc, gpio_chip_hwgpio(desc),
+ LINE_MODE_OPEN_DRAIN);
+ if (!ret)
+ goto set_output_value;
+ }
+ /* Emulate open drain by not actively driving the line high */
+ if (value)
+ return gpiod_direction_input(desc);
+ }
+ else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
+ if (gc->set_single_ended) {
+ ret = gc->set_single_ended(gc, gpio_chip_hwgpio(desc),
+ LINE_MODE_OPEN_SOURCE);
+ if (!ret)
+ goto set_output_value;
+ }
+ /* Emulate open source by not actively driving the line low */
+ if (!value)
+ return gpiod_direction_input(desc);
+ } else {
+ /* Make sure to disable open drain/source hardware, if any */
+ if (gc->set_single_ended)
+ gc->set_single_ended(gc,
+ gpio_chip_hwgpio(desc),
+ LINE_MODE_PUSH_PULL);
+ }