diff options
Diffstat (limited to 'drivers/video/hdmi.c')
| -rw-r--r-- | drivers/video/hdmi.c | 308 |
1 files changed, 308 insertions, 0 deletions
diff --git a/drivers/video/hdmi.c b/drivers/video/hdmi.c new file mode 100644 index 0000000..ab23c9b --- /dev/null +++ b/drivers/video/hdmi.c @@ -0,0 +1,308 @@ +/* + * 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); |