drm: add Atmel HLCDC Display Controller support

The Atmel HLCDC (HLCD Controller) IP available on some Atmel SoCs (i.e.
at91sam9n12, at91sam9x5 family or sama5d3 family) provides a display
controller device.

This display controller supports at least one primary plane and might
provide several overlays and an hardware cursor depending on the IP
version.

At the moment, this driver only implements an RGB connector to interface
with LCD panels, but support for other kind of external devices might be
added later.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Tested-by: Anthony Harivel <anthony.harivel@emtrion.de>
Tested-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>

drivers/gpu/drm/Kconfig

@@ -183,6 +183,8 @@ source "drivers/gpu/drm/cirrus/Kconfig"
 
 source "drivers/gpu/drm/armada/Kconfig"
 
+source "drivers/gpu/drm/atmel-hlcdc/Kconfig"
+
 source "drivers/gpu/drm/rcar-du/Kconfig"
 
 source "drivers/gpu/drm/shmobile/Kconfig"

drivers/gpu/drm/Makefile

@@ -54,6 +54,7 @@ obj-$(CONFIG_DRM_GMA500) += gma500/
 obj-$(CONFIG_DRM_UDL) += udl/
 obj-$(CONFIG_DRM_AST) += ast/
 obj-$(CONFIG_DRM_ARMADA) += armada/
+obj-$(CONFIG_DRM_ATMEL_HLCDC)	+= atmel-hlcdc/
 obj-$(CONFIG_DRM_RCAR_DU) += rcar-du/
 obj-$(CONFIG_DRM_SHMOBILE) +=shmobile/
 obj-$(CONFIG_DRM_OMAP)	+= omapdrm/

drivers/gpu/drm/atmel-hlcdc/Kconfig

@@ -0,0 +1,11 @@
+config DRM_ATMEL_HLCDC
+	tristate "DRM Support for ATMEL HLCDC Display Controller"
+	depends on DRM && OF && COMMON_CLK && MFD_ATMEL_HLCDC
+	select DRM_GEM_CMA_HELPER
+	select DRM_KMS_HELPER
+	select DRM_KMS_FB_HELPER
+	select DRM_KMS_CMA_HELPER
+	select DRM_PANEL
+	help
+	  Choose this option if you have an ATMEL SoC with an HLCDC display
+	  controller (i.e. at91sam9n12, at91sam9x5 family or sama5d3 family).

drivers/gpu/drm/atmel-hlcdc/Makefile

@@ -0,0 +1,7 @@
+atmel-hlcdc-dc-y := atmel_hlcdc_crtc.o \
+		atmel_hlcdc_dc.o \
+		atmel_hlcdc_layer.o \
+		atmel_hlcdc_output.o \
+		atmel_hlcdc_plane.o
+
+obj-$(CONFIG_DRM_ATMEL_HLCDC)	+= atmel-hlcdc-dc.o