gpio: qpnp-gpio: Issue lookups based on device name

qpnp-gpio manages gpio_chip queries based on the slave
ID. This has a limitation in that it restricts the number of
gpio_chips per slave ID to one. However, some PMICs have both MPP
and GPIO on the same slave, and thus the slave ID is not a
meaningful unit to search for.

Instead, make use of the 'label' binding to give the
primary dev-container node a name. This name will serve as the
gpio_chip label, which can be used in lookups.

Change-Id: Ic20caeb4622d73449a983992275446c733ddd89a
Signed-off-by: Michael Bohan <mbohan@codeaurora.org>
4 files changed