diff options
Diffstat (limited to 'src/platformsupport/edid/qedidparser.cpp')
| -rw-r--r-- | src/platformsupport/edid/qedidparser.cpp | 177 |
1 files changed, 177 insertions, 0 deletions
diff --git a/src/platformsupport/edid/qedidparser.cpp b/src/platformsupport/edid/qedidparser.cpp new file mode 100644 index 0000000000..ccf12e9eb3 --- /dev/null +++ b/src/platformsupport/edid/qedidparser.cpp @@ -0,0 +1,177 @@ +/**************************************************************************** +** +** Copyright (C) 2017 Pier Luigi Fiorini <pierluigi.fiorini@gmail.com> +** Contact: https://www.qt.io/licensing/ +** +** This file is part of the plugins of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** Commercial License Usage +** Licensees holding valid commercial Qt licenses may use this file in +** accordance with the commercial license agreement provided with the +** Software or, alternatively, in accordance with the terms contained in +** a written agreement between you and The Qt Company. For licensing terms +** and conditions see https://www.qt.io/terms-conditions. For further +** information use the contact form at https://www.qt.io/contact-us. +** +** GNU Lesser General Public License Usage +** Alternatively, this file may be used under the terms of the GNU Lesser +** General Public License version 3 as published by the Free Software +** Foundation and appearing in the file LICENSE.LGPL3 included in the +** packaging of this file. Please review the following information to +** ensure the GNU Lesser General Public License version 3 requirements +** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. +** +** GNU General Public License Usage +** Alternatively, this file may be used under the terms of the GNU +** General Public License version 2.0 or (at your option) the GNU General +** Public license version 3 or any later version approved by the KDE Free +** Qt Foundation. The licenses are as published by the Free Software +** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 +** included in the packaging of this file. Please review the following +** information to ensure the GNU General Public License requirements will +** be met: https://www.gnu.org/licenses/gpl-2.0.html and +** https://www.gnu.org/licenses/gpl-3.0.html. +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include <QtCore/QFile> + +#include "qedidparser_p.h" +#include "qedidvendortable_p.h" + +#define ARRAY_LENGTH(a) (sizeof (a) / sizeof (a)[0]) + +#define EDID_DESCRIPTOR_ALPHANUMERIC_STRING 0xfe +#define EDID_DESCRIPTOR_PRODUCT_NAME 0xfc +#define EDID_DESCRIPTOR_SERIAL_NUMBER 0xff + +#define EDID_OFFSET_DATA_BLOCKS 0x36 +#define EDID_OFFSET_LAST_BLOCK 0x6c +#define EDID_OFFSET_PNP_ID 0x08 +#define EDID_OFFSET_SERIAL 0x0c +#define EDID_PHYSICAL_WIDTH 0x15 +#define EDID_OFFSET_PHYSICAL_HEIGHT 0x16 + +QT_BEGIN_NAMESPACE + +QEdidParser::QEdidParser() +{ + // Cache vendors list from pnp.ids + const QString fileName = QLatin1String("/usr/share/hwdata/pnp.ids"); + if (QFile::exists(fileName)) { + QFile file(fileName); + + if (file.open(QFile::ReadOnly)) { + while (!file.atEnd()) { + QString line = QString::fromUtf8(file.readLine()).trimmed(); + + if (line.startsWith(QLatin1Char('#'))) + continue; + + QStringList parts = line.split(QLatin1Char('\t')); + if (parts.count() > 1) { + QString pnpId = parts.at(0); + parts.removeFirst(); + m_vendorCache[pnpId] = parts.join(QLatin1Char(' ')); + } + } + + file.close(); + } + } +} + +bool QEdidParser::parse(const QByteArray &blob) +{ + const quint8 *data = reinterpret_cast<const quint8 *>(blob.constData()); + const size_t length = blob.length(); + + // Verify header + if (length < 128) + return false; + if (data[0] != 0x00 || data[1] != 0xff) + return false; + + /* Decode the PNP ID from three 5 bit words packed into 2 bytes + * /--08--\/--09--\ + * 7654321076543210 + * |\---/\---/\---/ + * R C1 C2 C3 */ + char id[3]; + id[0] = 'A' + ((data[EDID_OFFSET_PNP_ID] & 0x7c) / 4) - 1; + id[1] = 'A' + ((data[EDID_OFFSET_PNP_ID] & 0x3) * 8) + ((data[EDID_OFFSET_PNP_ID + 1] & 0xe0) / 32) - 1; + id[2] = 'A' + (data[EDID_OFFSET_PNP_ID + 1] & 0x1f) - 1; + identifier = QString::fromLatin1(id, 3); + + // Clear manufacturer + manufacturer = QString(); + + // Serial number, will be overwritten by an ASCII descriptor + // when and if it will be found + quint32 serial = data[EDID_OFFSET_SERIAL] + + (data[EDID_OFFSET_SERIAL + 1] << 8) + + (data[EDID_OFFSET_SERIAL + 2] << 16) + + (data[EDID_OFFSET_SERIAL + 3] << 24); + if (serial > 0) + serialNumber = QString::number(serial); + else + serialNumber = QString(); + + // Parse EDID data + for (int i = 0; i < 5; ++i) { + const uint offset = EDID_OFFSET_DATA_BLOCKS + i * 18; + + if (data[offset] != 0 || data[offset + 1] != 0 || data[offset + 2] != 0) + continue; + + if (data[offset + 3] == EDID_DESCRIPTOR_PRODUCT_NAME) + model = parseEdidString(&data[offset + 5]); + else if (data[offset + 3] == EDID_DESCRIPTOR_ALPHANUMERIC_STRING) + identifier = parseEdidString(&data[offset + 5]); + else if (data[offset + 3] == EDID_DESCRIPTOR_SERIAL_NUMBER) + serialNumber = parseEdidString(&data[offset + 5]); + } + + // Try to use cache first because it is potentially more updated + if (m_vendorCache.contains(identifier)) { + manufacturer = m_vendorCache[identifier]; + } else { + // Find the manufacturer from the vendor lookup table + for (size_t i = 0; i < ARRAY_LENGTH(q_edidVendorTable); i++) { + if (strcmp(q_edidVendorTable[i].id, identifier.toLatin1().constData()) == 0) { + manufacturer = QString::fromUtf8(q_edidVendorTable[i].name); + break; + } + } + } + + // If we don't know the manufacturer, fallback to PNP ID + if (manufacturer.isEmpty()) + manufacturer = identifier; + + // Physical size + physicalSize = QSizeF(data[EDID_PHYSICAL_WIDTH], data[EDID_OFFSET_PHYSICAL_HEIGHT]) * 10; + + return true; +} + +QString QEdidParser::parseEdidString(const quint8 *data) +{ + QByteArray buffer(reinterpret_cast<const char *>(data), 12); + + // Erase carriage return and line feed + buffer = buffer.replace('\r', '\0').replace('\n', '\0'); + + // Replace non-printable characters with dash + for (int i = 0; i < buffer.count(); ++i) { + if (buffer[i] < '\040' && buffer[i] > '\176') + buffer[i] = '-'; + } + + return QString::fromLatin1(buffer.trimmed()); +} + +QT_END_NAMESPACE |