From 270afb37ae34fc1499d166f6edf4bc472f529d96 Mon Sep 17 00:00:00 2001 From: Uma Shankar Date: Thu, 16 May 2019 19:40:16 +0530 Subject: video/hdmi: Add Unpack function for DRM infoframe Added unpack function for DRM infoframe for dynamic range and mastering infoframe readout. v2: Addressed Ville's review comments. Suggested-by: Ville Syrjälä Signed-off-by: Uma Shankar Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/1558015817-12025-12-git-send-email-uma.shankar@intel.com --- drivers/video/hdmi.c | 67 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 67 insertions(+) (limited to 'drivers/video') diff --git a/drivers/video/hdmi.c b/drivers/video/hdmi.c index 481f0367dfd3..b99ba01dfed5 100644 --- a/drivers/video/hdmi.c +++ b/drivers/video/hdmi.c @@ -1804,6 +1804,70 @@ hdmi_vendor_any_infoframe_unpack(union hdmi_vendor_any_infoframe *frame, return 0; } +/** + * hdmi_drm_infoframe_unpack() - unpack binary buffer to a HDMI DRM infoframe + * @frame: HDMI DRM infoframe + * @buffer: source buffer + * @size: size of buffer + * + * Unpacks the information contained in binary @buffer into a structured + * @frame of the HDMI Dynamic Range and Mastering (DRM) information frame. + * Also verifies the checksum as required by section 5.3.5 of the HDMI 1.4 + * specification. + * + * Returns 0 on success or a negative error code on failure. + */ +static int hdmi_drm_infoframe_unpack(struct hdmi_drm_infoframe *frame, + const void *buffer, size_t size) +{ + const u8 *ptr = buffer; + const u8 *temp; + u8 x_lsb, x_msb; + u8 y_lsb, y_msb; + int ret; + int i; + + if (size < HDMI_INFOFRAME_SIZE(DRM)) + return -EINVAL; + + if (ptr[0] != HDMI_INFOFRAME_TYPE_DRM || + ptr[1] != 1 || + ptr[2] != HDMI_DRM_INFOFRAME_SIZE) + return -EINVAL; + + if (hdmi_infoframe_checksum(buffer, HDMI_INFOFRAME_SIZE(DRM)) != 0) + return -EINVAL; + + ret = hdmi_drm_infoframe_init(frame); + if (ret) + return ret; + + ptr += HDMI_INFOFRAME_HEADER_SIZE; + + frame->eotf = ptr[0] & 0x7; + frame->metadata_type = ptr[1] & 0x7; + + temp = ptr + 2; + for (i = 0; i < 3; i++) { + x_lsb = *temp++; + x_msb = *temp++; + frame->display_primaries[i].x = (x_msb << 8) | x_lsb; + y_lsb = *temp++; + y_msb = *temp++; + frame->display_primaries[i].y = (y_msb << 8) | y_lsb; + } + + frame->white_point.x = (ptr[15] << 8) | ptr[14]; + frame->white_point.y = (ptr[17] << 8) | ptr[16]; + + frame->max_display_mastering_luminance = (ptr[19] << 8) | ptr[18]; + frame->min_display_mastering_luminance = (ptr[21] << 8) | ptr[20]; + frame->max_cll = (ptr[23] << 8) | ptr[22]; + frame->max_fall = (ptr[25] << 8) | ptr[24]; + + return 0; +} + /** * hdmi_infoframe_unpack() - unpack binary buffer to a HDMI infoframe * @frame: HDMI infoframe @@ -1830,6 +1894,9 @@ int hdmi_infoframe_unpack(union hdmi_infoframe *frame, case HDMI_INFOFRAME_TYPE_AVI: ret = hdmi_avi_infoframe_unpack(&frame->avi, buffer, size); break; + case HDMI_INFOFRAME_TYPE_DRM: + ret = hdmi_drm_infoframe_unpack(&frame->drm, buffer, size); + break; case HDMI_INFOFRAME_TYPE_SPD: ret = hdmi_spd_infoframe_unpack(&frame->spd, buffer, size); break; -- cgit v1.2.3-55-g7522