[PATCH 07/12] video/hdmi: Introduce helpers for the HDMI vendor specific infoframe

Damien Lespiau
2013-08-13T23:17:23Z

Provide the programming model than the other infoframe types.

The generic _pack() function can't handle those yet as we need to move
the vendor OUI in the generic hdmi_vendor_infoframe structure to know
which kind of vendor infoframe we are dealing with.

Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
---
drivers/video/hdmi.c | 82 ++++++++++++++++++++++++++++++++++++++++++++++++++++
include/linux/hdmi.h | 25 ++++++++++++++++
2 files changed, 107 insertions(+)

diff --git a/drivers/video/hdmi.c b/drivers/video/hdmi.c
index ac84215..2059f7b 100644
--- a/drivers/video/hdmi.c
+++ b/drivers/video/hdmi.c
@@ -286,6 +286,88 @@ ssize_t hdmi_audio_infoframe_pack(struct hdmi_audio_infoframe *frame,
EXPORT_SYMBOL(hdmi_audio_infoframe_pack);

/**
+ * hdmi_hdmi_infoframe_init() - initialize an HDMI vendor infoframe
+ * @frame: HDMI vendor infoframe
+ *
+ * Returns 0 on success or a negative error code on failure.
+ */
+int hdmi_hdmi_infoframe_init(struct hdmi_hdmi_infoframe *frame)
+{
+ memset(frame, 0, sizeof(*frame));
+
+ frame->type = HDMI_INFOFRAME_TYPE_VENDOR;
+ frame->version = 1;
+ frame->length = 5; /* we can hardcode the size for now as we don't
+ support neither 3D_Ext_Data nor 3D_Metadata_* */
+
+ /* 0 is a valid value for s3d_struct, so we use a special "not set"
+ * value */
+ frame->s3d_struct = HDMI_3D_STRUCTURE_INVALID;
+
+ return 0;
+}
+EXPORT_SYMBOL(hdmi_hdmi_infoframe_init);
+
+/**
+ * hdmi_hmdi_infoframe_pack() - write a HDMI vendor infoframe to binary buffer
+ * @frame: HDMI 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.
+ *
+ * Returns the number of bytes packed into the binary buffer or a negative
+ * error code on failure.
+ */
+ssize_t hdmi_hdmi_infoframe_pack(struct hdmi_hdmi_infoframe *frame,
+ void *buffer, size_t size)
+{
+ u8 *ptr = buffer;
+ size_t length;
+
+ /* empty info frame */
+ if (frame->vic == 0 && frame->s3d_struct == HDMI_3D_STRUCTURE_INVALID)
+ return -EINVAL;
+
+ /* only one of those can be supplied */
+ if (frame->vic != 0 && frame->s3d_struct != HDMI_3D_STRUCTURE_INVALID)
+ return -EINVAL;
+
+ length = HDMI_INFOFRAME_HEADER_SIZE + frame->length;
+
+ if (size < length)
+ return -ENOSPC;
+
+ memset(buffer, 0, size);
+
+ ptr[0] = frame->type;
+ ptr[1] = frame->version;
+ ptr[2] = frame->length;
+ ptr[3] = 0; /* checksum */
+
+ /* HDMI OUI */
+ ptr[4] = 0x03;
+ ptr[5] = 0x0c;
+ ptr[6] = 0x00;
+
+ if (frame->vic) {
+ ptr[7] = 0x1 << 5; /* video format */
+ ptr[8] = frame->vic;
+ } else {
+ ptr[7] = 0x2 << 5; /* video format */
+ ptr[8] = (frame->s3d_struct & 0xf) << 4;
+ }
+
+ hdmi_infoframe_checksum(buffer, length);
+
+ return length;
+}
+EXPORT_SYMBOL(hdmi_hdmi_infoframe_pack);
+
+/**
* hdmi_vendor_infoframe_pack() - write a HDMI vendor infoframe to binary
* buffer
* @frame: HDMI vendor infoframe
diff --git a/include/linux/hdmi.h b/include/linux/hdmi.h
index b98340b..f5098a8 100644
--- a/include/linux/hdmi.h
+++ b/include/linux/hdmi.h
@@ -234,11 +234,36 @@ struct hdmi_vendor_infoframe {
ssize_t hdmi_vendor_infoframe_pack(struct hdmi_vendor_infoframe *frame,
void *buffer, size_t size);

+enum hdmi_3d_structure {
+ HDMI_3D_STRUCTURE_INVALID = -1,
+ HDMI_3D_STRUCTURE_FRAME_PACKING = 0,
+ HDMI_3D_STRUCTURE_FIELD_ALTERNATIVE,
+ HDMI_3D_STRUCTURE_LINE_ALTERNATIVE,
+ HDMI_3D_STRUCTURE_SIDE_BY_SIDE_FULL,
+ HDMI_3D_STRUCTURE_L_DEPTH,
+ HDMI_3D_STRUCTURE_L_DEPTH_GFX_GFX_DEPTH,
+ HDMI_3D_STRUCTURE_TOP_BOTTOM,
+ HDMI_3D_STRUCTURE_SIDE_BY_SIDE_HALF,
+};
+
+struct hdmi_hdmi_infoframe {
+ enum hdmi_infoframe_type type;
+ unsigned char version;
+ unsigned char length;
+ u8 vic;
+ enum hdmi_3d_structure s3d_struct;
+};
+
+int hdmi_hdmi_infoframe_init(struct hdmi_hdmi_infoframe *frame);
+ssize_t hdmi_hdmi_infoframe_pack(struct hdmi_hdmi_infoframe *frame,
+ void *buffer, size_t size);
+
union hdmi_infoframe {
struct hdmi_any_infoframe any;
struct hdmi_avi_infoframe avi;
struct hdmi_spd_infoframe spd;
struct hdmi_vendor_infoframe vendor;
+ struct hdmi_hdmi_infoframe hdmi;
struct hdmi_audio_infoframe audio;
};

--
1.8.3.1