diff options
Diffstat (limited to 'src/lib/edid.c')
| -rw-r--r-- | src/lib/edid.c | 105 |
1 files changed, 0 insertions, 105 deletions
diff --git a/src/lib/edid.c b/src/lib/edid.c deleted file mode 100644 index fc7b498..0000000 --- a/src/lib/edid.c +++ /dev/null @@ -1,105 +0,0 @@ -/* See LICENSE file for copyright and license details. */ -#include "edid.h" - -#include "libgamma-method.h" -#include "libgamma-error.h" - -#include <stdint.h> - - -/* - * EDID structure revision 1.1: - * http://en.wikipedia.org/w/index.php?title=Extended_display_identification_data&oldid=46295569 - * - * EDID structure revision 1.3: - * http://en.wikipedia.org/wiki/Extended_display_identification_data - */ - - -/** - * Parse the EDID of a monitor - * - * @param this Instance of a data structure to fill with the information about the EDID; - * it must contain the EDID and its length - * @param fields OR:ed identifiers for the information about the EDID that should be parsed; - * fields that do not have to do with EDID are ignored - * @return Non-zero on error - */ -int -libgamma_parse_edid(libgamma_crtc_information_t *restrict this, int32_t fields) -{ -#define __test_version(edid, major, minor_min, minor_max)\ - ((edid)[18] == (major) && (minor_min) <= (edid)[19] && (edid)[19] <= (minor_max)) -#define __m(value)\ - (this->edid[index++] != (value)) - - int error = 0, checksum = 0; - size_t i, index = 0; - - /* If the length of the EDID is not 128 bytes, we know that it is not of EDID - structure revision 1.0–1.3, and thus we do not support it. Additionally - this make sure we do not do segmentation violation on the next test. */ - if (this->edid_length != 128) - error = LIBGAMMA_EDID_LENGTH_UNSUPPORTED; - /* Check that the magic number of that of the EDID structure. */ - else if (__m(0x00) || __m(0xFF) || __m(0xFF) || __m(0xFF) || __m(0xFF) || __m(0xFF) || __m(0xFF) || __m(0x00)) - error = LIBGAMMA_EDID_WRONG_MAGIC_NUMBER; - /* Check that EDID structure revision 1.1–1.3 is used, those are the only - version we support. EDID structure revision 1.3 is also by far the most - commonly use revision and it is currently the newest revision. We know - that parsing works for both revision 1.1 and revision 1.3, because of - this we assume it is also correct for revision 1.2. However, we are not - assuming this for revision 1.0 which appeared in August 1994 and was - replaced by revision 1.1 in April 1996. */ - else if (!__test_version(this->edid, 1, 1, 3)) - error = LIBGAMMA_EDID_REVISION_UNSUPPORTED; - - /* If we have encountered an error, report it for the fields that require - the EDID to be parsed. Note that it is not stored for the EDID field - itself because it is not considered an error just because we do not - support the used version. */ - this->width_mm_edid_error = this->height_mm_edid_error = this->gamma_error = error; - - /* Retrieve the size of the viewport. This is done even if it is not - requested because it is not worth it branch. */ - this->width_mm_edid = (size_t)this->edid[21] * 10; - this->height_mm_edid = (size_t)this->edid[22] * 10; - - /* Retrieve the monitor's gamma characteristics. */ - if ((fields & LIBGAMMA_CRTC_INFO_GAMMA) && !error) { - if (this->edid[23] == 0xFF) { - /* If the gamma charactistics is FFh (3,55) it should be interpreted as not specified. */ - this->gamma_error = LIBGAMMA_GAMMA_NOT_SPECIFIED; - } else { - this->gamma_blue = (float)((int)this->edid[23] + 100) / 100.f; - this->gamma_red = this->gamma_green = this->gamma_blue; - } - } - - /* If not error has occurred, calculate and test the checksum. - It is not considered an error that the gamma characteristics - is left unspecified in the EDID. */ - if (!error) { - for (i = 0; i < this->edid_length; i++) - checksum += (int)this->edid[i]; - } - /* The checksum should be zero. */ - if (checksum & 255) { - /* Store the error in all fields that require the EDID to be parsed, - as well as the EDID field itself. */ - error = LIBGAMMA_EDID_CHECKSUM_ERROR; - this->edid_error = this->width_mm_edid_error = this->height_mm_edid_error = error; - /* If the gamma characteristics is not specified, that is kept, - and the checksum error is augmented. */ - this->gamma_error = this->gamma_error == LIBGAMMA_GAMMA_NOT_SPECIFIED - ? LIBGAMMA_GAMMA_NOT_SPECIFIED_AND_EDID_CHECKSUM_ERROR : error; - } - - /* Return whether or not we encountered an error or if - the gamma characteristics was requested but is not - specified in the monitor's EDID. */ - return error | this->gamma_error; - -#undef __m -#undef __test_version -} |