Add generic helpers to pack HDMI infoframes into a binary buffers.

Signed-off-by: Thierry Reding <thierry.reding at avionic-design.de>
---
 drivers/video/Kconfig  |   3 ++
 drivers/video/Makefile |   1 +
 drivers/video/hdmi.c   |  84 ++++++++++++++++++++++++++++++++++
 include/linux/hdmi.h   | 119 +++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 207 insertions(+)
 create mode 100644 drivers/video/hdmi.c
 create mode 100644 include/linux/hdmi.h

diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index fb9a14e..17ac897 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -52,6 +52,9 @@ config OF_VIDEOMODE
        help
          helper to get videomodes from the devicetree

+config HDMI
+       bool
+
 menuconfig FB
        tristate "Support for frame buffer devices"
        ---help---
diff --git a/drivers/video/Makefile b/drivers/video/Makefile
index b936b00..d1d38ea 100644
--- a/drivers/video/Makefile
+++ b/drivers/video/Makefile
@@ -5,6 +5,7 @@
 # Each configuration option enables a list of files.

 obj-$(CONFIG_VGASTATE)            += vgastate.o
+obj-$(CONFIG_HDMI)                += hdmi.o
 obj-y                             += fb_notify.o
 obj-$(CONFIG_FB)                  += fb.o
 fb-y                              := fbmem.o fbmon.o fbcmap.o fbsysfs.o \
diff --git a/drivers/video/hdmi.c b/drivers/video/hdmi.c
new file mode 100644
index 0000000..3d6ee5e
--- /dev/null
+++ b/drivers/video/hdmi.c
@@ -0,0 +1,84 @@
+/*
+ * Copyright (C) 2012 Avionic Design GmbH
+ *
+ * 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.
+ */
+
+#include <linux/bitops.h>
+#include <linux/errno.h>
+#include <linux/export.h>
+#include <linux/hdmi.h>
+
+/**
+ * hdmi_avi_infoframe_pack() - write HDMI AVI infoframe to binary buffer
+ * @frame: HDMI AVI infoframe
+ * @buffer: destination buffer
+ * @size: size of buffer
+ *
+ * Packs the information contained in the @frame structure into a binary
+ * representation that can be written into the corresponding controller
+ * registers. Also computes the checksum as required by section 5.3.5 of the
+ * HDMI 1.4 specification.
+ */
+ssize_t hdmi_avi_infoframe_pack(struct hdmi_avi_infoframe *frame, void *buffer,
+                               size_t size)
+{
+       u8 *ptr = buffer;
+       unsigned int i;
+       u8 csum = 0;
+
+       if (frame->length > 0x1f)
+               return -EINVAL;
+
+       ptr[0] = frame->type;
+       ptr[1] = frame->version;
+       ptr[2] = frame->length;
+       ptr[3] = 0; /* checksum */
+       ptr[4] = ((frame->colorspace & 0x3) << 5) | (frame->scan_mode & 0x3);
+
+       if (frame->active_info_valid)
+               ptr[4] |= BIT(4);
+
+       if (frame->horizontal_bar_valid)
+               ptr[4] |= BIT(3);
+
+       if (frame->vertical_bar_valid)
+               ptr[4] |= BIT(2);
+
+       ptr[5] = ((frame->colorimetry & 0x3) << 6) |
+                ((frame->picture_aspect & 0x3) << 4) |
+                (frame->active_aspect & 0xf);
+
+       ptr[6] = ((frame->extended_colorimetry & 0x7) << 4) |
+                ((frame->quantization_range & 0x3) << 2) |
+                (frame->nups & 0x3);
+
+       if (frame->itc)
+               ptr[6] |= BIT(7);
+
+       ptr[7] = frame->video_code & 0x7f;
+
+       ptr[8] = ((frame->ycc_quantization_range & 0x3) << 6) |
+                ((frame->content_type & 0x3) << 4) |
+                (frame->pixel_repeat & 0xf);
+
+       ptr[9] = frame->top_bar & 0xff;
+       ptr[10] = (frame->top_bar >> 8) & 0xff;
+       ptr[11] = frame->bottom_bar & 0xff;
+       ptr[12] = (frame->bottom_bar >> 8) & 0xff;
+       ptr[13] = frame->left_bar & 0xff;
+       ptr[14] = (frame->left_bar >> 8) & 0xff;
+       ptr[15] = frame->right_bar & 0xff;
+       ptr[16] = (frame->right_bar >> 8) & 0xff;
+
+       /* compute checksum */
+       for (i = 0; i < 4 + frame->length; i++)
+               csum += ptr[i];
+
+       ptr[3] = 256 - csum;
+
+       return 4 + frame->length;
+}
+EXPORT_SYMBOL_GPL(hdmi_avi_infoframe_pack);
diff --git a/include/linux/hdmi.h b/include/linux/hdmi.h
new file mode 100644
index 0000000..132556f
--- /dev/null
+++ b/include/linux/hdmi.h
@@ -0,0 +1,119 @@
+/*
+ * Copyright (C) 2012 Avionic Design GmbH
+ *
+ * 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 __LINUX_HDMI_H_
+#define __LINUX_HDMI_H_
+
+#include <linux/types.h>
+
+enum hdmi_infoframe_type {
+       HDMI_INFOFRAME_TYPE_AVI,
+};
+
+enum hdmi_colorspace {
+       HDMI_COLORSPACE_RGB,
+       HDMI_COLORSPACE_YUV422,
+       HDMI_COLORSPACE_YUV444,
+};
+
+enum hdmi_scan_mode {
+       HDMI_SCAN_MODE_NONE,
+       HDMI_SCAN_MODE_OVERSCAN,
+       HDMI_SCAN_MODE_UNDERSCAN,
+};
+
+enum hdmi_colorimetry {
+       HDMI_COLORIMETRY_NONE,
+       HDMI_COLORIMETRY_ITU_601,
+       HDMI_COLORIMETRY_ITU_709,
+       HDMI_COLORIMETRY_EXTENDED,
+};
+
+enum hdmi_picture_aspect {
+       HDMI_PICTURE_ASPECT_NONE,
+       HDMI_PICTURE_ASPECT_4_3,
+       HDMI_PICTURE_ASPECT_16_9,
+};
+
+enum hdmi_active_aspect {
+       HDMI_ACTIVE_ASPECT_16_9_TOP = 2,
+       HDMI_ACTIVE_ASPECT_14_9_TOP = 3,
+       HDMI_ACTIVE_ASPECT_16_9_CENTER = 4,
+       HDMI_ACTIVE_ASPECT_PICTURE = 8,
+       HDMI_ACTIVE_ASPECT_4_3 = 9,
+       HDMI_ACTIVE_ASPECT_16_9 = 10,
+       HDMI_ACTIVE_ASPECT_14_9 = 11,
+       HDMI_ACTIVE_ASPECT_4_3_SP_14_9 = 13,
+       HDMI_ACTIVE_ASPECT_16_9_SP_14_9 = 14,
+       HDMI_ACTIVE_ASPECT_16_9_SP_4_3 = 15,
+};
+
+enum hdmi_extended_colorimetry {
+       HDMI_EXTENDED_COLORIMETRY_XV_YCC_601,
+       HDMI_EXTENDED_COLORIMETRY_XV_YCC_709,
+       HDMI_EXTENDED_COLORIMETRY_S_YCC_601,
+       HDMI_EXTENDED_COLORIMETRY_ADOBE_YCC_601,
+       HDMI_EXTENDED_COLORIMETRY_ADOBE_RGB,
+};
+
+enum hdmi_quantization_range {
+       HDMI_QUANTIZATION_RANGE_DEFAULT,
+       HDMI_QUANTIZATION_RANGE_LIMITED,
+       HDMI_QUANTIZATION_RANGE_FULL,
+};
+
+/* non-uniform picture scaling */
+enum hdmi_nups {
+       HDMI_NUPS_UNKNOWN,
+       HDMI_NUPS_HORIZONTAL,
+       HDMI_NUPS_VERTICAL,
+       HDMI_NUPS_BOTH,
+};
+
+enum hdmi_ycc_quantization_range {
+       HDMI_YCC_QUANTIZATION_RANGE_LIMITED,
+       HDMI_YCC_QUANTIZATION_RANGE_FULL,
+};
+
+enum hdmi_content_type {
+       HDMI_CONTENT_TYPE_NONE,
+       HDMI_CONTENT_TYPE_PHOTO,
+       HDMI_CONTENT_TYPE_CINEMA,
+       HDMI_CONTENT_TYPE_GAME,
+};
+
+struct hdmi_avi_infoframe {
+       enum hdmi_infoframe_type type;
+       unsigned char version;
+       unsigned char length;
+       enum hdmi_colorspace colorspace;
+       bool active_info_valid;
+       bool horizontal_bar_valid;
+       bool vertical_bar_valid;
+       enum hdmi_scan_mode scan_mode;
+       enum hdmi_colorimetry colorimetry;
+       enum hdmi_picture_aspect picture_aspect;
+       enum hdmi_active_aspect active_aspect;
+       bool itc;
+       enum hdmi_extended_colorimetry extended_colorimetry;
+       enum hdmi_quantization_range quantization_range;
+       enum hdmi_nups nups;
+       unsigned char video_code;
+       enum hdmi_ycc_quantization_range ycc_quantization_range;
+       enum hdmi_content_type content_type;
+       unsigned char pixel_repeat;
+       unsigned short top_bar;
+       unsigned short bottom_bar;
+       unsigned short left_bar;
+       unsigned short right_bar;
+};
+
+ssize_t hdmi_avi_infoframe_pack(struct hdmi_avi_infoframe *frame, void *buffer,
+                               size_t size);
+
+#endif /* _DRM_HDMI_H */
-- 
1.8.0

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