[PATCH v2 06/18] video/hdmi: Add Unpack only function for DRM infoframe
From: Gwan-gyeong Mun <hidden>
Date: 2020-02-02 15:50:05
Also in:
dri-devel, intel-gfx
Subsystem:
framebuffer layer, the rest · Maintainers:
Helge Deller, Linus Torvalds
It adds an unpack only function for DRM infoframe for dynamic range and mastering infoframe readout. It unpacks the information data block contained in the binary buffer into a structured frame of the HDMI Dynamic Range and Mastering (DRM) information frame. In contrast to hdmi_drm_infoframe_unpack() function, it does not verify a checksum. It can be used for unpacking a DP HDR Metadata Infoframe SDP case. DP HDR Metadata Infoframe SDP uses the same Dynamic Range and Mastering (DRM) information (CTA-861-G spec.) such as HDMI DRM infoframe. But DP SDP header and payload structure are different from HDMI DRM Infoframe. Therefore unpacking DRM infoframe for DP requires skipping of a verifying checksum. Signed-off-by: Gwan-gyeong Mun <redacted> --- drivers/video/hdmi.c | 58 +++++++++++++++++++++++++++++++------------- include/linux/hdmi.h | 2 ++ 2 files changed, 43 insertions(+), 17 deletions(-)
diff --git a/drivers/video/hdmi.c b/drivers/video/hdmi.c
index 9c82e2a0a411..9818836d82b7 100644
--- a/drivers/video/hdmi.c
+++ b/drivers/video/hdmi.c@@ -1775,20 +1775,18 @@ hdmi_vendor_any_infoframe_unpack(union hdmi_vendor_any_infoframe *frame, } /** - * hdmi_drm_infoframe_unpack() - unpack binary buffer to a HDMI DRM infoframe + * hdmi_drm_infoframe_unpack_only() - 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 + * Unpacks the information data block 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) +int hdmi_drm_infoframe_unpack_only(struct hdmi_drm_infoframe *frame, + const void *buffer, size_t size) { const u8 *ptr = buffer; const u8 *temp;
@@ -1797,23 +1795,13 @@ static int hdmi_drm_infoframe_unpack(struct hdmi_drm_infoframe *frame, 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) + if (size < HDMI_DRM_INFOFRAME_SIZE) 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;
@@ -1837,6 +1825,42 @@ static int hdmi_drm_infoframe_unpack(struct hdmi_drm_infoframe *frame, return 0; } +EXPORT_SYMBOL(hdmi_drm_infoframe_unpack_only); + +/** + * 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; + int ret; + + 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_unpack_only(frame, ptr + HDMI_INFOFRAME_HEADER_SIZE, + size - HDMI_INFOFRAME_HEADER_SIZE); + return ret; +} /** * hdmi_infoframe_unpack() - unpack binary buffer to a HDMI infoframe
diff --git a/include/linux/hdmi.h b/include/linux/hdmi.h
index 9918a6c910c5..afb43efc03e0 100644
--- a/include/linux/hdmi.h
+++ b/include/linux/hdmi.h@@ -219,6 +219,8 @@ ssize_t hdmi_drm_infoframe_pack(struct hdmi_drm_infoframe *frame, void *buffer, ssize_t hdmi_drm_infoframe_pack_only(const struct hdmi_drm_infoframe *frame, void *buffer, size_t size); int hdmi_drm_infoframe_check(struct hdmi_drm_infoframe *frame); +int hdmi_drm_infoframe_unpack_only(struct hdmi_drm_infoframe *frame, + const void *buffer, size_t size); enum hdmi_spd_sdi { HDMI_SPD_SDI_UNKNOWN,
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2.24.1