On Tue, May 10, 2016 at 11:50:19AM +0200, Linus Walleij wrote:

Make it possible to name the producer side of a GPIO line using
a "gpio-line-names" property array, modeled on the
"clock-output-names" property from the clock bindings.

This naming is especially useful for:

- Debugging: lines are named after function, not just opaque
  offset numbers.

- Exploration: systems where some or all GPIO lines are available
  to end users, such as prototyping, one-off's "makerspace usecases"
  users are helped by the names of the GPIO lines when tinkering.
  This usecase has been surfacing recently.

The gpio-line-names attribute is completely optional.

Example output from lsgpio on a patched Snowball tree:

GPIO chip: gpiochip6, "8000e180.gpio", 32 GPIO lines
        line  0: unnamed unused
        line  1: "AP_GPIO161" "extkb3" [kernel]
        line  2: "AP_GPIO162" "extkb4" [kernel]
        line  3: "ACCELEROMETER_INT1_RDY" unused [kernel]
        line  4: "ACCELEROMETER_INT2" unused
        line  5: "MAG_DRDY" unused [kernel]
        line  6: "GYRO_DRDY" unused [kernel]
        line  7: "RSTn_MLC" unused
        line  8: "RSTn_SLC" unused
        line  9: "GYRO_INT" unused
        line 10: "UART_WAKE" unused
        line 11: "GBF_RESET" unused
        line 12: unnamed unused

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Grant Likely <redacted>
Cc: Amit Kucheria <redacted>
Cc: David Mandala <redacted>
Cc: Lee Campbell <redacted>
Cc: devicetree@vger.kernel.org
Reviewed-by: Michael Welling <redacted>
Signed-off-by: Linus Walleij <redacted>

Trying to make me reconsider my ack on the previous v4? ;)

Acked-by: Rob Herring <robh@kernel.org>