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Diffstat (limited to 'libmate-desktop/edid-parse.c')
-rw-r--r--libmate-desktop/edid-parse.c536
1 files changed, 536 insertions, 0 deletions
diff --git a/libmate-desktop/edid-parse.c b/libmate-desktop/edid-parse.c
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index 0000000..842e327
--- /dev/null
+++ b/libmate-desktop/edid-parse.c
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+/*
+ * Copyright 2007 Red Hat, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * on the rights to use, copy, modify, merge, publish, distribute, sub
+ * license, and/or sell copies of the Software, and to permit persons to whom
+ * the Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/* Author: Soren Sandmann <[email protected]> */
+
+#include "edid.h"
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+#include <glib.h>
+
+static int get_bit(int in, int bit)
+{
+ return (in & (1 << bit)) >> bit;
+}
+
+static int get_bits(int in, int begin, int end)
+{
+ int mask = (1 << (end - begin + 1)) - 1;
+
+ return (in >> begin) & mask;
+}
+
+static int decode_header(const uchar* edid)
+{
+ if (memcmp(edid, "\x00\xff\xff\xff\xff\xff\xff\x00", 8) == 0)
+ {
+ return TRUE;
+ }
+
+ return FALSE;
+}
+
+static int decode_vendor_and_product_identification(const uchar* edid, MonitorInfo* info)
+{
+ int is_model_year;
+
+ /* Manufacturer Code */
+ info->manufacturer_code[0] = get_bits(edid[0x08], 2, 6);
+ info->manufacturer_code[1] = get_bits(edid[0x08], 0, 1) << 3;
+ info->manufacturer_code[1] |= get_bits(edid[0x09], 5, 7);
+ info->manufacturer_code[2] = get_bits(edid[0x09], 0, 4);
+ info->manufacturer_code[3] = '\0';
+
+ info->manufacturer_code[0] += 'A' - 1;
+ info->manufacturer_code[1] += 'A' - 1;
+ info->manufacturer_code[2] += 'A' - 1;
+
+ /* Product Code */
+ info->product_code = edid[0x0b] << 8 | edid[0x0a];
+
+ /* Serial Number */
+ info->serial_number = edid[0x0c] | edid[0x0d] << 8 | edid[0x0e] << 16 | edid[0x0f] << 24;
+
+ /* Week and Year */
+ is_model_year = FALSE;
+
+ switch (edid[0x10])
+ {
+ case 0x00:
+ info->production_week = -1;
+ break;
+
+ case 0xff:
+ info->production_week = -1;
+ is_model_year = TRUE;
+ break;
+
+ default:
+ info->production_week = edid[0x10];
+ break;
+ }
+
+ if (is_model_year)
+ {
+ info->production_year = -1;
+ info->model_year = 1990 + edid[0x11];
+ }
+ else
+ {
+ info->production_year = 1990 + edid[0x11];
+ info->model_year = -1;
+ }
+
+ return TRUE;
+}
+
+static int decode_edid_version(const uchar* edid, MonitorInfo* info)
+{
+ info->major_version = edid[0x12];
+ info->minor_version = edid[0x13];
+
+ return TRUE;
+}
+
+static int decode_display_parameters(const uchar* edid, MonitorInfo* info)
+{
+ /* Digital vs Analog */
+ info->is_digital = get_bit(edid[0x14], 7);
+
+ if (info->is_digital)
+ {
+ int bits;
+
+ static const int bit_depth[8] = {
+ -1, 6, 8, 10, 12, 14, 16, -1
+ };
+
+ static const Interface interfaces[6] = {
+ UNDEFINED, DVI, HDMI_A, HDMI_B, MDDI, DISPLAY_PORT
+ };
+
+ bits = get_bits(edid[0x14], 4, 6);
+ info->connector.digital.bits_per_primary = bit_depth[bits];
+
+ bits = get_bits(edid[0x14], 0, 3);
+
+ if (bits <= 5)
+ {
+ info->connector.digital.interface = interfaces[bits];
+ }
+ else
+ {
+ info->connector.digital.interface = UNDEFINED;
+ }
+ }
+ else
+ {
+ int bits = get_bits (edid[0x14], 5, 6);
+
+ static const double levels[][3] = {
+ { 0.7, 0.3, 1.0 },
+ { 0.714, 0.286, 1.0 },
+ { 1.0, 0.4, 1.4 },
+ { 0.7, 0.0, 0.7 },
+ };
+
+ info->connector.analog.video_signal_level = levels[bits][0];
+ info->connector.analog.sync_signal_level = levels[bits][1];
+ info->connector.analog.total_signal_level = levels[bits][2];
+
+ info->connector.analog.blank_to_black = get_bit (edid[0x14], 4);
+
+ info->connector.analog.separate_hv_sync = get_bit (edid[0x14], 3);
+ info->connector.analog.composite_sync_on_h = get_bit (edid[0x14], 2);
+ info->connector.analog.composite_sync_on_green = get_bit (edid[0x14], 1);
+
+ info->connector.analog.serration_on_vsync = get_bit (edid[0x14], 0);
+ }
+
+ /* Screen Size / Aspect Ratio */
+ if (edid[0x15] == 0 && edid[0x16] == 0)
+ {
+ info->width_mm = -1;
+ info->height_mm = -1;
+ info->aspect_ratio = -1.0;
+ }
+ else if (edid[0x16] == 0)
+ {
+ info->width_mm = -1;
+ info->height_mm = -1;
+ info->aspect_ratio = 100.0 / (edid[0x15] + 99);
+ }
+ else if (edid[0x15] == 0)
+ {
+ info->width_mm = -1;
+ info->height_mm = -1;
+ info->aspect_ratio = 100.0 / (edid[0x16] + 99);
+ info->aspect_ratio = 1/info->aspect_ratio; /* portrait */
+ }
+ else
+ {
+ info->width_mm = 10 * edid[0x15];
+ info->height_mm = 10 * edid[0x16];
+ }
+
+ /* Gamma */
+ if (edid[0x17] == 0xFF)
+ info->gamma = -1.0;
+ else
+ info->gamma = (edid[0x17] + 100.0) / 100.0;
+
+ /* Features */
+ info->standby = get_bit(edid[0x18], 7);
+ info->suspend = get_bit(edid[0x18], 6);
+ info->active_off = get_bit(edid[0x18], 5);
+
+ if (info->is_digital)
+ {
+ info->connector.digital.rgb444 = TRUE;
+
+ if (get_bit(edid[0x18], 3))
+ info->connector.digital.ycrcb444 = 1;
+ if (get_bit(edid[0x18], 4))
+ info->connector.digital.ycrcb422 = 1;
+ }
+ else
+ {
+ int bits = get_bits(edid[0x18], 3, 4);
+
+ ColorType color_type[4] = {
+ MONOCHROME, RGB, OTHER_COLOR, UNDEFINED_COLOR
+ };
+
+ info->connector.analog.color_type = color_type[bits];
+ }
+
+ info->srgb_is_standard = get_bit(edid[0x18], 2);
+
+ /* In 1.3 this is called "has preferred timing" */
+ info->preferred_timing_includes_native = get_bit(edid[0x18], 1);
+
+ /* FIXME: In 1.3 this indicates whether the monitor accepts GTF */
+ info->continuous_frequency = get_bit(edid[0x18], 0);
+
+ return TRUE;
+}
+
+static double decode_fraction(int high, int low)
+{
+ double result = 0.0;
+ int i;
+
+ high = (high << 2) | low;
+
+ for (i = 0; i < 10; ++i)
+ {
+ result += get_bit (high, i) * pow (2, i - 10);
+ }
+
+ return result;
+}
+
+static int decode_color_characteristics(const uchar* edid, MonitorInfo* info)
+{
+ info->red_x = decode_fraction(edid[0x1b], get_bits(edid[0x19], 6, 7));
+ info->red_y = decode_fraction(edid[0x1c], get_bits(edid[0x19], 5, 4));
+ info->green_x = decode_fraction(edid[0x1d], get_bits(edid[0x19], 2, 3));
+ info->green_y = decode_fraction(edid[0x1e], get_bits(edid[0x19], 0, 1));
+ info->blue_x = decode_fraction(edid[0x1f], get_bits(edid[0x1a], 6, 7));
+ info->blue_y = decode_fraction(edid[0x20], get_bits(edid[0x1a], 4, 5));
+ info->white_x = decode_fraction(edid[0x21], get_bits(edid[0x1a], 2, 3));
+ info->white_y = decode_fraction(edid[0x22], get_bits(edid[0x1a], 0, 1));
+
+ return TRUE;
+}
+
+static int decode_established_timings(const uchar* edid, MonitorInfo* info)
+{
+ static const Timing established[][8] = {
+ {
+ {800, 600, 60},
+ {800, 600, 56},
+ {640, 480, 75},
+ {640, 480, 72},
+ {640, 480, 67},
+ {640, 480, 60},
+ {720, 400, 88},
+ {720, 400, 70}
+ },
+ {
+ {1280, 1024, 75},
+ {1024, 768, 75},
+ {1024, 768, 70},
+ {1024, 768, 60},
+ {1024, 768, 87},
+ {832, 624, 75},
+ {800, 600, 75},
+ {800, 600, 72}
+ },
+ {
+ {0, 0, 0},
+ {0, 0, 0},
+ {0, 0, 0},
+ {0, 0, 0},
+ {0, 0, 0},
+ {0, 0, 0},
+ {0, 0, 0},
+ {1152, 870, 75}
+ },
+ };
+
+ int i, j, idx;
+
+ idx = 0;
+
+ for (i = 0; i < 3; ++i)
+ {
+ for (j = 0; j < 8; ++j)
+ {
+ int byte = edid[0x23 + i];
+
+ if (get_bit (byte, j) && established[i][j].frequency != 0)
+ {
+ info->established[idx++] = established[i][j];
+ }
+ }
+ }
+
+ return TRUE;
+}
+
+static int decode_standard_timings(const uchar* edid, MonitorInfo* info)
+{
+ int i;
+
+ for (i = 0; i < 8; i++)
+ {
+ int first = edid[0x26 + 2 * i];
+ int second = edid[0x27 + 2 * i];
+
+ if (first != 0x01 && second != 0x01)
+ {
+ int w = 8 * (first + 31);
+ int h;
+
+ switch (get_bits(second, 6, 7))
+ {
+ case 0x00:
+ h = (w / 16) * 10;
+ break;
+ case 0x01:
+ h = (w / 4) * 3;
+ break;
+ case 0x02:
+ h = (w / 5) * 4;
+ break;
+ case 0x03:
+ h = (w / 16) * 9;
+ break;
+ }
+
+ info->standard[i].width = w;
+ info->standard[i].height = h;
+ info->standard[i].frequency = get_bits(second, 0, 5) + 60;
+ }
+ }
+
+ return TRUE;
+}
+
+static void decode_lf_string(const uchar* s, int n_chars, char* result)
+{
+ int i;
+
+ for (i = 0; i < n_chars; ++i)
+ {
+ if (s[i] == 0x0a)
+ {
+ *result++ = '\0';
+ break;
+ }
+ else if (s[i] == 0x00)
+ {
+ /* Convert embedded 0's to spaces */
+ *result++ = ' ';
+ }
+ else
+ {
+ *result++ = s[i];
+ }
+ }
+}
+
+static void decode_display_descriptor(const uchar* desc, MonitorInfo* info)
+{
+ switch (desc[0x03])
+ {
+ case 0xFC:
+ decode_lf_string (desc + 5, 13, info->dsc_product_name);
+ break;
+ case 0xFF:
+ decode_lf_string (desc + 5, 13, info->dsc_serial_number);
+ break;
+ case 0xFE:
+ decode_lf_string (desc + 5, 13, info->dsc_string);
+ break;
+ case 0xFD:
+ /* Range Limits */
+ break;
+ case 0xFB:
+ /* Color Point */
+ break;
+ case 0xFA:
+ /* Timing Identifications */
+ break;
+ case 0xF9:
+ /* Color Management */
+ break;
+ case 0xF8:
+ /* Timing Codes */
+ break;
+ case 0xF7:
+ /* Established Timings */
+ break;
+ case 0x10:
+ break;
+ }
+}
+
+static void decode_detailed_timing(const uchar* timing, DetailedTiming* detailed)
+{
+ int bits;
+
+ StereoType stereo[] = {
+ NO_STEREO, NO_STEREO, FIELD_RIGHT, FIELD_LEFT,
+ TWO_WAY_RIGHT_ON_EVEN, TWO_WAY_LEFT_ON_EVEN,
+ FOUR_WAY_INTERLEAVED, SIDE_BY_SIDE
+ };
+
+ detailed->pixel_clock = (timing[0x00] | timing[0x01] << 8) * 10000;
+ detailed->h_addr = timing[0x02] | ((timing[0x04] & 0xf0) << 4);
+ detailed->h_blank = timing[0x03] | ((timing[0x04] & 0x0f) << 8);
+ detailed->v_addr = timing[0x05] | ((timing[0x07] & 0xf0) << 4);
+ detailed->v_blank = timing[0x06] | ((timing[0x07] & 0x0f) << 8);
+ detailed->h_front_porch = timing[0x08] | get_bits(timing[0x0b], 6, 7) << 8;
+ detailed->h_sync = timing[0x09] | get_bits(timing[0x0b], 4, 5) << 8;
+ detailed->v_front_porch =
+ get_bits (timing[0x0a], 4, 7) | get_bits(timing[0x0b], 2, 3) << 4;
+ detailed->v_sync =
+ get_bits (timing[0x0a], 0, 3) | get_bits(timing[0x0b], 0, 1) << 4;
+ detailed->width_mm = timing[0x0c] | get_bits(timing[0x0e], 4, 7) << 8;
+ detailed->height_mm = timing[0x0d] | get_bits(timing[0x0e], 0, 3) << 8;
+ detailed->right_border = timing[0x0f];
+ detailed->top_border = timing[0x10];
+
+ detailed->interlaced = get_bit(timing[0x11], 7);
+
+ /* Stereo */
+ bits = get_bits (timing[0x11], 5, 6) << 1 | get_bit(timing[0x11], 0);
+ detailed->stereo = stereo[bits];
+
+ /* Sync */
+ bits = timing[0x11];
+
+ detailed->digital_sync = get_bit(bits, 4);
+
+ if (detailed->digital_sync)
+ {
+ detailed->connector.digital.composite = !get_bit(bits, 3);
+
+ if (detailed->connector.digital.composite)
+ {
+ detailed->connector.digital.serrations = get_bit(bits, 2);
+ detailed->connector.digital.negative_vsync = FALSE;
+ }
+ else
+ {
+ detailed->connector.digital.serrations = FALSE;
+ detailed->connector.digital.negative_vsync = !get_bit(bits, 2);
+ }
+
+ detailed->connector.digital.negative_hsync = !get_bit(bits, 0);
+ }
+ else
+ {
+ detailed->connector.analog.bipolar = get_bit(bits, 3);
+ detailed->connector.analog.serrations = get_bit(bits, 2);
+ detailed->connector.analog.sync_on_green = !get_bit(bits, 1);
+ }
+}
+
+static int decode_descriptors(const uchar* edid, MonitorInfo* info)
+{
+ int i;
+ int timing_idx;
+
+ timing_idx = 0;
+
+ for (i = 0; i < 4; ++i)
+ {
+ int index = 0x36 + i * 18;
+
+ if (edid[index + 0] == 0x00 && edid[index + 1] == 0x00)
+ {
+ decode_display_descriptor(edid + index, info);
+ }
+ else
+ {
+ decode_detailed_timing(edid + index, &(info->detailed_timings[timing_idx++]));
+ }
+ }
+
+ info->n_detailed_timings = timing_idx;
+
+ return TRUE;
+}
+
+static void decode_check_sum(const uchar* edid, MonitorInfo* info)
+{
+ int i;
+ uchar check = 0;
+
+ for (i = 0; i < 128; ++i)
+ {
+ check += edid[i];
+ }
+
+ info->checksum = check;
+}
+
+MonitorInfo* decode_edid(const uchar* edid)
+{
+ MonitorInfo* info = g_new0(MonitorInfo, 1);
+
+ decode_check_sum(edid, info);
+
+ if (decode_header(edid) && decode_vendor_and_product_identification(edid, info) && decode_edid_version(edid, info) && decode_display_parameters(edid, info) && decode_color_characteristics(edid, info) && decode_established_timings(edid, info) && decode_standard_timings(edid, info) && decode_descriptors(edid, info))
+ {
+ return info;
+ }
+ else
+ {
+ g_free(info);
+ return NULL;
+ }
+}
generated by cgit v1.2.1 (git 2.18.0) at 2024-11-02 22:01:27 +0000