From 7d27becb3532d881378846e72864031977be511a Mon Sep 17 00:00:00 2001 From: "Lespiau, Damien" Date: Mon, 19 Aug 2013 16:58:58 +0100 Subject: video/hdmi: Introduce helpers for the HDMI vendor specific infoframe MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Provide the same 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. v2: Fix the value of Side-by-side (half), hmdi typo, pack 3D_Ext_Data (Ville Syrjälä) v3: Future proof the sending of 3D_Ext_Data (Ville Syrjälä), Fix multi-lines comment style (Thierry Reding) Signed-off-by: Damien Lespiau Reviewed-by: Ville Syrjälä Reviewed-by: Thierry Reding Signed-off-by: Dave Airlie --- drivers/video/hdmi.c | 90 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 90 insertions(+) (limited to 'drivers/video/hdmi.c') diff --git a/drivers/video/hdmi.c b/drivers/video/hdmi.c index 1201357f3e3c..4c42bcb86535 100644 --- a/drivers/video/hdmi.c +++ b/drivers/video/hdmi.c @@ -287,6 +287,96 @@ 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; + + /* + * 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_hdmi_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; + + /* for side by side (half) we also need to provide 3D_Ext_Data */ + if (frame->s3d_struct >= HDMI_3D_STRUCTURE_SIDE_BY_SIDE_HALF) + frame->length = 6; + else + frame->length = 5; + + 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; + if (frame->s3d_struct >= HDMI_3D_STRUCTURE_SIDE_BY_SIDE_HALF) + ptr[9] = (frame->s3d_ext_data & 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 -- cgit v1.2.3