drm: zte: add tvenc driver support

It adds the TV Encoder driver to support video output in PAL and NTSC
format.  The driver uses syscon/regmap interface to configure register
bit sitting in SYSCTRL module for DAC power control.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Sean Paul <seanpaul@chromium.org>

drivers/gpu/drm/zte/Makefile

@@ -2,6 +2,7 @@ zxdrm-y := \
 	zx_drm_drv.o \
 	zx_hdmi.o \
 	zx_plane.o \
+	zx_tvenc.o \
 	zx_vou.o
 
 obj-$(CONFIG_DRM_ZTE) += zxdrm.o

drivers/gpu/drm/zte/zx_drm_drv.c

@@ -247,6 +247,7 @@ static struct platform_driver zx_drm_platform_driver = {
 static struct platform_driver *drivers[] = {
 	&zx_crtc_driver,
 	&zx_hdmi_driver,
+	&zx_tvenc_driver,
 	&zx_drm_platform_driver,
 };
 

drivers/gpu/drm/zte/zx_drm_drv.h

@@ -13,6 +13,7 @@
 
 extern struct platform_driver zx_crtc_driver;
 extern struct platform_driver zx_hdmi_driver;
+extern struct platform_driver zx_tvenc_driver;
 
 static inline u32 zx_readl(void __iomem *reg)
 {

drivers/gpu/drm/zte/zx_tvenc_regs.h

+/*
+ * Copyright 2017 Linaro Ltd.
+ * Copyright 2017 ZTE Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#ifndef __ZX_TVENC_REGS_H__
+#define __ZX_TVENC_REGS_H__
+
+#define VENC_VIDEO_INFO			0x04
+#define VENC_VIDEO_RES			0x08
+#define VENC_FIELD1_PARAM		0x10
+#define VENC_FIELD2_PARAM		0x14
+#define VENC_LINE_O_1			0x18
+#define VENC_LINE_E_1			0x1c
+#define VENC_LINE_O_2			0x20
+#define VENC_LINE_E_2			0x24
+#define VENC_LINE_TIMING_PARAM		0x28
+#define VENC_WEIGHT_VALUE		0x2c
+#define VENC_BLANK_BLACK_LEVEL		0x30
+#define VENC_BURST_LEVEL		0x34
+#define VENC_CONTROL_PARAM		0x3c
+#define VENC_SUB_CARRIER_PHASE1		0x40
+#define VENC_PHASE_LINE_INCR_CVBS	0x48
+#define VENC_ENABLE			0xa8
+
+#endif /* __ZX_TVENC_REGS_H__ */

drivers/gpu/drm/zte/zx_vou.c

@@ -199,6 +199,11 @@ static struct vou_inf vou_infs[] = {
 		.clocks_en_bits = BIT(24) | BIT(18) | BIT(6),
 		.clocks_sel_bits = BIT(13) | BIT(2),
 	},
+	[VOU_TV_ENC] = {
+		.data_sel = VOU_YUV444,
+		.clocks_en_bits = BIT(15),
+		.clocks_sel_bits = BIT(11) | BIT(0),
+	},
 };
 
 static inline struct zx_vou_hw *crtc_to_vou(struct drm_crtc *crtc)