drm/exynos: mic: add MIC driver

MIC(Mobile image compressor) is newly added IP in Exynos5433. MIC
resides between decon and mipi dsim, and compresses frame data by 50%.
With dsi, not display port, to send frame data to the panel, the
bandwidth is not enough. That is why this compressor is introduced.
Signed-off-by: Hyungwon Hwang <human.hwang@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

Documentation/devicetree/bindings/video/exynos-mic.txt

+Device-Tree bindings for Samsung Exynos SoC mobile image compressor (MIC)
+
+MIC (mobile image compressor) resides between decon and mipi dsi. Mipi dsi is
+not capable to transfer high resoltuion frame data as decon can send. MIC
+solves this problem by compressing the frame data by 1/2 before it is
+transferred through mipi dsi. The compressed frame data must be uncompressed in
+the panel PCB.
+
+Required properties:
+- compatible: value should be "samsung,exynos5433-mic".
+- reg: physical base address and length of the MIC registers set and system
+       register of mic.
+- clocks: must include clock specifiers corresponding to entries in the
+	  clock-names property.
+- clock-names: list of clock names sorted in the same order as the clocks
+	       property. Must contain "pclk_mic0", "sclk_rgb_vclk_to_mic0".
+- samsung,disp-syscon: the reference node for syscon for DISP block.
+- ports: contains a port which is connected to decon node and dsi node.
+	 address-cells and size-cells must 1 and 0, respectively.
+- port: contains an endpoint node which is connected to the endpoint in the
+	decon node or dsi node. The reg value must be 0 and 1 respectively.
+
+Example:
+SoC specific DT entry:
+mic: mic@13930000 {
+	compatible = "samsung,exynos5433-mic";
+	reg = <0x13930000 0x48>;
+	clocks = <&cmu_disp CLK_PCLK_MIC0>,
+	       <&cmu_disp CLK_SCLK_RGB_VCLK_TO_MIC0>;
+	clock-names = "pclk_mic0", "sclk_rgb_vclk_to_mic0";
+	samsung,disp-syscon = <&syscon_disp>;
+
+	ports {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		port@0 {
+			reg = <0>;
+			mic_to_decon: endpoint {
+				remote-endpoint = <&decon_to_mic>;
+			};
+		};
+
+		port@1 {
+			reg = <1>;
+			mic_to_dsi: endpoint {
+				remote-endpoint = <&dsi_to_mic>;
+			};
+		};
+	};
+};

drivers/gpu/drm/exynos/Kconfig

@@ -103,3 +103,9 @@ config DRM_EXYNOS_GSC
 	depends on DRM_EXYNOS_IPP && ARCH_EXYNOS5 && !ARCH_MULTIPLATFORM
 	help
 	  Choose this option if you want to use Exynos GSC for DRM.
+
+config DRM_EXYNOS_MIC
+	bool "Exynos DRM MIC"
+	depends on (DRM_EXYNOS && DRM_EXYNOS5433_DECON)
+	help
+	  Choose this option if you want to use Exynos MIC for DRM.

drivers/gpu/drm/exynos/Makefile

@@ -22,5 +22,6 @@ exynosdrm-$(CONFIG_DRM_EXYNOS_IPP)	+= exynos_drm_ipp.o
 exynosdrm-$(CONFIG_DRM_EXYNOS_FIMC)	+= exynos_drm_fimc.o
 exynosdrm-$(CONFIG_DRM_EXYNOS_ROTATOR)	+= exynos_drm_rotator.o
 exynosdrm-$(CONFIG_DRM_EXYNOS_GSC)	+= exynos_drm_gsc.o
+exynosdrm-$(CONFIG_DRM_EXYNOS_MIC)     += exynos_drm_mic.o
 
 obj-$(CONFIG_DRM_EXYNOS)		+= exynosdrm.o

drivers/gpu/drm/exynos/exynos_drm_drv.c

@@ -357,6 +357,9 @@ static struct platform_driver *const exynos_drm_kms_drivers[] = {
 #ifdef CONFIG_DRM_EXYNOS7_DECON
 	&decon_driver,
 #endif
+#ifdef CONFIG_DRM_EXYNOS_MIC
+	&mic_driver,
+#endif
 #ifdef CONFIG_DRM_EXYNOS_DP
 	&dp_driver,
 #endif
@@ -370,9 +373,6 @@ static struct platform_driver *const exynos_drm_kms_drivers[] = {
 };
 
 static struct platform_driver *const exynos_drm_non_kms_drivers[] = {
-#ifdef CONFIG_DRM_EXYNOS_MIC
-	&mic_driver,
-#endif
 #ifdef CONFIG_DRM_EXYNOS_G2D
 	&g2d_driver,
 #endif

drivers/gpu/drm/exynos/exynos_drm_drv.h

@@ -314,4 +314,5 @@ extern struct platform_driver fimc_driver;
 extern struct platform_driver rotator_driver;
 extern struct platform_driver gsc_driver;
 extern struct platform_driver ipp_driver;
+extern struct platform_driver mic_driver;
 #endif