dm: video: Add a video uclass

U-Boot has separate code for LCDs and 'video' devices. Both now use a
very similar API thanks to earlier work by Nikita Kiryanov. With the driver-
model conversion we should unify these into a single uclass.

Unfortunately there are different features supported by each. This
implementation provides for a common set of features which should serve
most purposes. The intent is to support:

- bitmap devices with 8, 16 and 32 bits per pixel
- text console wih white on black or vice versa
- rotated text console
- bitmap display (BMP format)

More can be added as additional boards are ported over to use driver model
for video.

The name 'video' is chosen for the uclass since it is more generic than LCD.
Another option would be 'display' but that would introduce a third concept
to U-Boot which seems like the wrong approach.

The existing LCD and video init functions are not needed now, so this uclass
makes no attempt to implement them.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Anatolij Gustschin <agust@denx.de>

2 files changed, 163 insertions, 6 deletions

diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
index 27fa0b6..3934375 100644
--- a/include/dm/uclass-id.h
+++ b/include/dm/uclass-id.h
@@ -66,6 +66,7 @@ enum uclass_id {
 	UCLASS_USB,		/* USB bus */
 	UCLASS_USB_DEV_GENERIC,	/* USB generic device */
 	UCLASS_USB_HUB,		/* USB hub */
+	UCLASS_VIDEO,		/* Video or LCD device */
 	UCLASS_VIDEO_BRIDGE,	/* Video bridge, e.g. DisplayPort to LVDS */
 
 	UCLASS_COUNT,
diff --git a/include/video.h b/include/video.h
index 65e4ec1..b20f06f 100644
--- a/include/video.h
+++ b/include/video.h
@@ -1,14 +1,167 @@
 /*
-** MPC823 Video Controller
-** =======================
-** (C) 2000 by Paolo Scaffardi (arsenio@tin.it)
-** AIRVENT SAM s.p.a - RIMINI(ITALY)
-**
-*/
+ * Video uclass and legacy implementation
+ *
+ * Copyright (c) 2015 Google, Inc
+ *
+ * MPC823 Video Controller
+ * =======================
+ * (C) 2000 by Paolo Scaffardi (arsenio@tin.it)
+ * AIRVENT SAM s.p.a - RIMINI(ITALY)
+ *
+ */
 
 #ifndef _VIDEO_H_
 #define _VIDEO_H_
 
+#ifdef CONFIG_DM_VIDEO
+
+#include <stdio_dev.h>
+
+struct video_uc_platdata {
+	uint align;
+	uint size;
+	ulong base;
+};
+
+/*
+ * Bits per pixel selector. Each value n is such that the bits-per-pixel is
+ * 2 ^ n
+ */
+enum video_log2_bpp {
+	VIDEO_BPP1	= 0,
+	VIDEO_BPP2,
+	VIDEO_BPP4,
+	VIDEO_BPP8,
+	VIDEO_BPP16,
+	VIDEO_BPP32,
+};
+
+/*
+ * Convert enum video_log2_bpp to bytes and bits. Note we omit the outer
+ * brackets to allow multiplication by fractional pixels.
+ */
+#define VNBYTES(bpix)	(1 << (bpix)) / 8
+
+#define VNBITS(bpix)	(1 << (bpix))
+
+/**
+ * struct video_priv - Device information used by the video uclass
+ *
+ * @xsize:	Number of pixel columns (e.g. 1366)
+ * @ysize:	Number of pixels rows (e.g.. 768)
+ * @tor:	Display rotation (0=none, 1=90 degrees clockwise, etc.)
+ * @bpix:	Encoded bits per pixel
+ * @fb:		Frame buffer
+ * @fb_size:	Frame buffer size
+ * @line_length:	Length of each frame buffer line, in bytes
+ * @colour_fg:	Foreground colour (pixel value)
+ * @colour_bg:	Background colour (pixel value)
+ * @flush_dcache:	true to enable flushing of the data cache after
+ *		the LCD is updated
+ * @cmap:	Colour map for 8-bit-per-pixel displays
+ */
+struct video_priv {
+	/* Things set up by the driver: */
+	ushort xsize;
+	ushort ysize;
+	ushort rot;
+	enum video_log2_bpp bpix;
+
+	/*
+	 * Things that are private to the uclass: don't use these in the
+	 * driver
+	 */
+	void *fb;
+	int fb_size;
+	int line_length;
+	int colour_fg;
+	int colour_bg;
+	bool flush_dcache;
+	ushort *cmap;
+};
+
+/* Placeholder - there are no video operations at present */
+struct video_ops {
+};
+
+#define video_get_ops(dev)        ((struct video_ops *)(dev)->driver->ops)
+
+/**
+ * video_reserve() - Reserve frame-buffer memory for video devices
+ *
+ * Note: This function is for internal use.
+ *
+ * This uses the uclass platdata's @size and @align members to figure out
+ * a size and position for each frame buffer as part of the pre-relocation
+ * process of determining the post-relocation memory layout.
+ *
+ * gd->video_top is set to the initial value of *@addrp and gd->video_bottom
+ * is set to the final value.
+ *
+ * @addrp:	On entry, the top of available memory. On exit, the new top,
+ *		after allocating the required memory.
+ * @return 0
+ */
+int video_reserve(ulong *addrp);
+
+/**
+ * video_sync() - Sync a device's frame buffer with its hardware
+ *
+ * Some frame buffers are cached or have a secondary frame buffer. This
+ * function syncs these up so that the current contents of the U-Boot frame
+ * buffer are displayed to the user.
+ *
+ * @dev:	Device to sync
+ */
+void video_sync(struct udevice *vid);
+
+/**
+ * video_sync_all() - Sync all devices' frame buffers with there hardware
+ *
+ * This calls video_sync() on all active video devices.
+ */
+void video_sync_all(void);
+
+/**
+ * video_bmp_display() - Display a BMP file
+ *
+ * @dev:	Device to display the bitmap on
+ * @bmp_image:	Address of bitmap image to display
+ * @x:		X position in pixels from the left
+ * @y:		Y position in pixels from the top
+ * @align:	true to adjust the coordinates to centre the image. If false
+ *		the coordinates are used as is. If true:
+ *
+ *		- if a coordinate is 0x7fff then the image will be centred in
+ *		  that direction
+ *		- if a coordinate is -ve then it will be offset to the
+ *		  left/top of the centre by that many pixels
+ *		- if a coordinate is positive it will be used unchnaged.
+ * @return 0 if OK, -ve on error
+ */
+int video_bmp_display(struct udevice *dev, ulong bmp_image, int x, int y,
+		      bool align);
+
+/**
+ * video_get_xsize() - Get the width of the display in pixels
+ *
+ * @dev:	Device to check
+ * @return device frame buffer width in pixels
+ */
+int video_get_xsize(struct udevice *dev);
+
+/**
+ * video_get_ysize() - Get the height of the display in pixels
+ *
+ * @dev:	Device to check
+ * @return device frame buffer height in pixels
+ */
+int video_get_ysize(struct udevice *dev);
+
+#endif /* CONFIG_DM_VIDEO */
+
+#ifndef CONFIG_DM_VIDEO
+
 /* Video functions */
 
 struct stdio_dev;
@@ -73,4 +226,7 @@ int kwh043st20_f01_spi_startup(unsigned int bus, unsigned int cs,
 int lg4573_spi_startup(unsigned int bus, unsigned int cs,
 	unsigned int max_hz, unsigned int spi_mode);
 #endif
+
+#endif /* CONFIG_DM_VIDEO */
+
 #endif