drm/mcde: Add new driver for ST-Ericsson MCDE

This adds a new DRM driver for the ST-Ericsson Multi Channel
Display Engine, MCDE display controller.

This hardware has three independent DSI hosts and can composit
and display several memory buffers onto an LCD display. It
was developed for several years inside of ST-Ericsson and
shipped with a few million mobile phones from Sony and Samsung,
as well as with the Snowball community development board.

The driver is currently pretty rudimentary but supports a
simple framebuffer so we can get penguins and graphics when
using these SoCs.
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190524092019.19355-1-linus.walleij@linaro.org

Documentation/gpu/drivers.rst

@@ -7,6 +7,7 @@ GPU Driver Documentation
    amdgpu
    amdgpu-dc
    i915
+   mcde
    meson
    pl111
    tegra

Documentation/gpu/mcde.rst

+.. SPDX-License-Identifier: GPL-2.0
+
+=======================================================
+ drm/mcde ST-Ericsson MCDE Multi-channel display engine
+=======================================================
+
+.. kernel-doc:: drivers/gpu/drm/mcde/mcde_drv.c
+   :doc: ST-Ericsson MCDE DRM Driver

MAINTAINERS

@@ -5128,6 +5128,13 @@ S:	Maintained
 F:	drivers/gpu/drm/tinydrm/st7735r.c
 F:	Documentation/devicetree/bindings/display/sitronix,st7735r.txt
 
+DRM DRIVER FOR ST-ERICSSON MCDE
+M:	Linus Walleij <linus.walleij@linaro.org>
+T:	git git://anongit.freedesktop.org/drm/drm-misc
+S:	Maintained
+F:	drivers/gpu/drm/mcde/
+F:	Documentation/devicetree/bindings/display/ste,mcde.txt
+
 DRM DRIVER FOR TDFX VIDEO CARDS
 S:	Orphan / Obsolete
 F:	drivers/gpu/drm/tdfx/

drivers/gpu/drm/Kconfig

@@ -349,6 +349,8 @@ source "drivers/gpu/drm/panfrost/Kconfig"
 
 source "drivers/gpu/drm/aspeed/Kconfig"
 
+source "drivers/gpu/drm/mcde/Kconfig"
+
 # Keep legacy drivers last
 
 menuconfig DRM_LEGACY

drivers/gpu/drm/Makefile

@@ -118,3 +118,4 @@ obj-$(CONFIG_DRM_VBOXVIDEO) += vboxvideo/
 obj-$(CONFIG_DRM_LIMA)  += lima/
 obj-$(CONFIG_DRM_PANFROST) += panfrost/
 obj-$(CONFIG_DRM_ASPEED_GFX) += aspeed/
+obj-$(CONFIG_DRM_MCDE) += mcde/

drivers/gpu/drm/mcde/Kconfig

+config DRM_MCDE
+	tristate "DRM Support for ST-Ericsson MCDE (Multichannel Display Engine)"
+	depends on DRM
+	depends on CMA
+	depends on ARM || COMPILE_TEST
+	depends on OF
+	select MFD_SYSCON
+	select DRM_MIPI_DSI
+	select DRM_BRIDGE
+	select DRM_PANEL_BRIDGE
+	select DRM_KMS_HELPER
+	select DRM_KMS_CMA_HELPER
+	select DRM_GEM_CMA_HELPER
+	select VT_HW_CONSOLE_BINDING if FRAMEBUFFER_CONSOLE
+	help
+	  Choose this option for DRM support for the ST-Ericsson MCDE
+	  Multi-Channel Display Engine.
+	  If M is selected the module will be called mcde_drm.

drivers/gpu/drm/mcde/Makefile

+mcde_drm-y +=	mcde_drv.o mcde_dsi.o mcde_display.o
+
+obj-$(CONFIG_DRM_MCDE) += mcde_drm.o

drivers/gpu/drm/mcde/mcde_drm.h

+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2018 Linus Walleij <linus.walleij@linaro.org>
+ * Parts of this file were based on the MCDE driver by Marcus Lorentzon
+ * (C) ST-Ericsson SA 2013
+ */
+#include <drm/drm_simple_kms_helper.h>
+
+#ifndef _MCDE_DRM_H_
+#define _MCDE_DRM_H_
+
+struct mcde {
+	struct drm_device drm;
+	struct device *dev;
+	struct drm_panel *panel;
+	struct drm_bridge *bridge;
+	struct drm_connector *connector;
+	struct drm_simple_display_pipe pipe;
+	struct mipi_dsi_device *mdsi;
+	s16 stride;
+	bool te_sync;
+	bool oneshot_mode;
+	unsigned int flow_active;
+	spinlock_t flow_lock; /* Locks the channel flow control */
+
+	void __iomem *regs;
+
+	struct clk *mcde_clk;
+	struct clk *lcd_clk;
+	struct clk *hdmi_clk;
+
+	struct regulator *epod;
+	struct regulator *vana;
+};
+
+bool mcde_dsi_irq(struct mipi_dsi_device *mdsi);
+void mcde_dsi_te_request(struct mipi_dsi_device *mdsi);
+extern struct platform_driver mcde_dsi_driver;
+
+void mcde_display_irq(struct mcde *mcde);
+void mcde_display_disable_irqs(struct mcde *mcde);
+int mcde_display_init(struct drm_device *drm);
+
+#endif /* _MCDE_DRM_H_ */