/* * 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> #include <linux/string.h> static void hdmi_infoframe_checksum(void *buffer, size_t size) { u8 *ptr = buffer; u8 csum = 0; size_t i; /* compute checksum */ for (i = 0; i < size; i++) csum += ptr[i]; ptr[3] = 256 - csum; } /** * hdmi_avi_infoframe_init() - initialize an HDMI AVI infoframe * @frame: HDMI AVI infoframe * * Returns 0 on success or a negative error code on failure. */ int hdmi_avi_infoframe_init(struct hdmi_avi_infoframe *frame) { memset(frame, 0, sizeof(*frame)); frame->type = HDMI_INFOFRAME_TYPE_AVI; frame->version = 2; frame->length = 13; return 0; } EXPORT_SYMBOL(hdmi_avi_infoframe_init); /** * 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. * * Returns the number of bytes packed into the binary buffer or a negative * error code on failure. */ ssize_t hdmi_avi_infoframe_pack(struct hdmi_avi_infoframe *frame, void *buffer, size_t size) { u8 *ptr = buffer; size_t length; length = HDMI_INFOFRAME_HEADER_SIZE + frame->length; if (size < length) return -ENOSPC; memset(buffer, 0, length); ptr[0] = frame->type; ptr[1] = frame->version; ptr[2] = frame->length; ptr[3] = 0; /* checksum */ /* start infoframe payload */ ptr += HDMI_INFOFRAME_HEADER_SIZE; ptr[0] = ((frame->colorspace & 0x3) << 5) | (frame->scan_mode & 0x3); if (frame->active_info_valid) ptr[0] |= BIT(4); if (frame->horizontal_bar_valid) ptr[0] |= BIT(3); if (frame->vertical_bar_valid) ptr[0] |= BIT(2); ptr[1] = ((frame->colorimetry & 0x3) << 6) | ((frame->picture_aspect & 0x3) << 4) | (frame->active_aspect & 0xf); ptr[2] = ((frame->extended_colorimetry & 0x7) << 4) | ((frame->quantization_range & 0x3) << 2) | (frame->nups & 0x3); if (frame->itc) ptr[2] |= BIT(7); ptr[3] = frame->video_code & 0x7f; ptr[4] = ((frame->ycc_quantization_range & 0x3) << 6) | ((frame->content_type & 0x3) << 4) | (frame->pixel_repeat & 0xf); ptr[5] = frame->top_bar & 0xff; ptr[6] = (frame->top_bar >> 8) & 0xff; ptr[7] = frame->bottom_bar & 0xff; ptr[8] = (frame->bottom_bar >> 8) & 0xff; ptr[9] = frame->left_bar & 0xff; ptr[10] = (frame->left_bar >> 8) & 0xff; ptr[11] = frame->right_bar & 0xff; ptr[12] = (frame->right_bar >> 8) & 0xff; hdmi_infoframe_checksum(buffer, length); return length; } EXPORT_SYMBOL(hdmi_avi_infoframe_pack); /** * hdmi_spd_infoframe_init() - initialize an HDMI SPD infoframe * @frame: HDMI SPD infoframe * @vendor: vendor string * @product: product string * * Returns 0 on success or a negative error code on failure. */ int hdmi_spd_infoframe_init(struct hdmi_spd_infoframe *frame, const char *vendor, const char *product) { memset(frame, 0, sizeof(*frame)); frame->type = HDMI_INFOFRAME_TYPE_SPD; frame->version = 1; frame->length = 25; strncpy(frame->vendor, vendor, sizeof(frame->vendor)); strncpy(frame->product, product, sizeof(frame->product)); return 0; } EXPORT_SYMBOL(hdmi_spd_infoframe_init); /** * hdmi_spd_infoframe_pack() - write HDMI SPD infoframe to binary buffer * @frame: HDMI SPD 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_spd_infoframe_pack(struct hdmi_spd_infoframe *frame, void *buffer, size_t size) { u8 *ptr = buffer; size_t length; length = HDMI_INFOFRAME_HEADER_SIZE + frame->length; if (size < length) return -ENOSPC; memset(buffer, 0, length); ptr[0] = frame->type; ptr[1] = frame->version; ptr[2] = frame->length; ptr[3] = 0; /* checksum */ /* start infoframe payload */ ptr += HDMI_INFOFRAME_HEADER_SIZE; memcpy(ptr, frame->vendor, sizeof(frame->vendor)); memcpy(ptr + 8, frame->product, sizeof(frame->product)); ptr[24] = frame->sdi; hdmi_infoframe_checksum(buffer, length); return length; } EXPORT_SYMBOL(hdmi_spd_infoframe_pack); /** * hdmi_audio_infoframe_init() - initialize an HDMI audio infoframe * @frame: HDMI audio infoframe * * Returns 0 on success or a negative error code on failure. */ int hdmi_audio_infoframe_init(struct hdmi_audio_infoframe *frame) { memset(frame, 0, sizeof(*frame)); frame->type = HDMI_INFOFRAME_TYPE_AUDIO; frame->version = 1; frame->length = 10; return 0; } EXPORT_SYMBOL(hdmi_audio_infoframe_init); /** * hdmi_audio_infoframe_pack() - write HDMI audio infoframe to binary buffer * @frame: HDMI audio 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_audio_infoframe_pack(struct hdmi_audio_infoframe *frame, void *buffer, size_t size) { unsigned char channels; u8 *ptr = buffer; size_t length; length = HDMI_INFOFRAME_HEADER_SIZE + frame->length; if (size < length) return -ENOSPC; memset(buffer, 0, length); if (frame->channels >= 2) channels = frame->channels - 1; else channels = 0; ptr[0] = frame->type; ptr[1] = frame->version; ptr[2] = frame->length; ptr[3] = 0; /* checksum */ /* start infoframe payload */ ptr += HDMI_INFOFRAME_HEADER_SIZE; ptr[0] = ((frame->coding_type & 0xf) << 4) | (channels & 0x7); ptr[1] = ((frame->sample_frequency & 0x7) << 2) | (frame->sample_size & 0x3); ptr[2] = frame->coding_type_ext & 0x1f; ptr[3] = frame->channel_allocation; ptr[4] = (frame->level_shift_value & 0xf) << 3; if (frame->downmix_inhibit) ptr[4] |= BIT(7); hdmi_infoframe_checksum(buffer, length); return length; } EXPORT_SYMBOL(hdmi_audio_infoframe_pack); /** * hdmi_vendor_infoframe_pack() - write a HDMI vendor infoframe to binary * buffer * @frame: HDMI vendor 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_vendor_infoframe_pack(struct hdmi_vendor_infoframe *frame, void *buffer, size_t size) { u8 *ptr = buffer; size_t length; length = HDMI_INFOFRAME_HEADER_SIZE + frame->length; if (size < length) return -ENOSPC; memset(buffer, 0, length); ptr[0] = frame->type; ptr[1] = frame->version; ptr[2] = frame->length; ptr[3] = 0; /* checksum */ memcpy(&ptr[HDMI_INFOFRAME_HEADER_SIZE], frame->data, frame->length); hdmi_infoframe_checksum(buffer, length); return length; } EXPORT_SYMBOL(hdmi_vendor_infoframe_pack);