dt-bindings: can: mcp251x: document GPIO support

The next patch adds gpio controller support to the mcp251x driver. This
patch updates the binding accordingly.

Cc: Timo Schlüßler <schluessler@krause.de>
Link: https://lore.kernel.org/r/20200915223527.1417033-26-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

dt-bindings: can: mcp251x: change example interrupt type to IRQ_TYPE_LEVEL_LOW

The MCP2515 datasheet clearly describes a level-triggered interrupt pin.
Change example bindings accordingly.

Link: https://lore.kernel.org/r/20200915223527.1417033-25-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

dt-bindings: can: mcp251x: add mcp25625 support

Fully compatible with mcp2515, the mcp25625 have integrated transceiver.

This patch add the mcp25625 to the device tree bindings documentation.

Signed-off-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

dt-bindings: remove 'interrupt-parent' from bindings

'interrupt-parent' is often documented as part of define bindings, but
it is really outside the scope of a device binding. It's never required
in a given node as it is often inherited from a parent node. Or it can
be implicit if a parent node is an 'interrupt-controller' node. So
remove it from all the binding files.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: devicetree@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>

can: mcp251x: Add device tree support

This patch adds Device Tree support to the Microchip MCP251X driver.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>