+++ /dev/null
-/*
- * VideoPort driver
- *
- * Copyright (C) 2002, 2003, 2004 ReactOS Team
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- *
- */
-
-#include "videoprt.h"
-
-#define DDC_EEPROM_ADDRESS 0xA0
-
-/* PRIVATE FUNCTIONS **********************************************************/
-
-#define LOW 0
-#define HIGH 1
-#define WRITE 0
-#define READ 1
-#define READ_SDA() (i2c->ReadDataLine(HwDeviceExtension))
-#define READ_SCL() (i2c->ReadClockLine(HwDeviceExtension))
-#define WRITE_SDA(state) (i2c->WriteDataLine(HwDeviceExtension, state))
-#define WRITE_SCL(state) (i2c->WriteClockLine(HwDeviceExtension, state))
-
-static LARGE_INTEGER HalfPeriodDelay = {{0, 70}};
-#define DELAY_HALF() KeDelayExecutionThread(KernelMode, FALSE, &HalfPeriodDelay)
-
-
-static BOOL
-I2CWrite(PVOID HwDeviceExtension, PI2C_CALLBACKS i2c, UCHAR Data)
-{
- UCHAR Bit;
- BOOL Ack;
-
- /* transmit data */
- for (Bit = (1 << 7); Bit != 0; Bit >>= 1)
- {
- WRITE_SCL(LOW);
- WRITE_SDA((Data & Bit) ? HIGH : LOW);
- DELAY_HALF();
- WRITE_SCL(HIGH);
- DELAY_HALF();
- }
-
- /* get ack */
- WRITE_SCL(LOW);
- WRITE_SDA(HIGH);
- DELAY_HALF();
- WRITE_SCL(HIGH);
- do
- {
- DELAY_HALF();
- }
- while (READ_SCL() != HIGH);
- Ack = (READ_SDA() == LOW);
- DELAY_HALF();
-
- INFO_(VIDEOPRT, "I2CWrite: %s\n", Ack ? "Ack" : "Nak");
- return Ack;
-}
-
-
-static UCHAR
-I2CRead(PVOID HwDeviceExtension, PI2C_CALLBACKS i2c, BOOL Ack)
-{
- INT Bit = 0x80;
- UCHAR Data = 0;
-
- /* pull down SCL and release SDA */
- WRITE_SCL(LOW);
- WRITE_SDA(HIGH);
-
- /* read byte */
- for (Bit = (1 << 7); Bit != 0; Bit >>= 1)
- {
- WRITE_SCL(LOW);
- DELAY_HALF();
- WRITE_SCL(HIGH);
- DELAY_HALF();
- if (READ_SDA() == HIGH)
- Data |= Bit;
- }
-
- /* send ack/nak */
- WRITE_SCL(LOW);
- WRITE_SDA(Ack ? LOW : HIGH);
- DELAY_HALF();
- WRITE_SCL(HIGH);
- do
- {
- DELAY_HALF();
- }
- while (READ_SCL() != HIGH);
-
- return Data;
-}
-
-
-static VOID
-I2CStop(PVOID HwDeviceExtension, PI2C_CALLBACKS i2c)
-{
- WRITE_SCL(LOW);
- WRITE_SDA(LOW);
- DELAY_HALF();
- WRITE_SCL(HIGH);
- DELAY_HALF();
- WRITE_SDA(HIGH);
-}
-
-
-static BOOL
-I2CStart(PVOID HwDeviceExtension, PI2C_CALLBACKS i2c, UCHAR Address)
-{
- /* make sure the bus is free */
- if (READ_SDA() == LOW || READ_SCL() == LOW)
- {
- WARN_(VIDEOPRT, "I2CStart: Bus is not free!\n");
- return FALSE;
- }
-
- /* send address */
- WRITE_SDA(LOW);
- DELAY_HALF();
- if (!I2CWrite(HwDeviceExtension, i2c, Address))
- {
- /* ??release the bus?? */
- I2CStop(HwDeviceExtension, i2c);
- WARN_(VIDEOPRT, "I2CStart: Device not found (Address = 0x%x)\n", Address);
- return FALSE;
- }
-
- INFO_(VIDEOPRT, "I2CStart: SUCCESS!\n");
- return TRUE;
-}
-
-
-static BOOL
-I2CRepStart(PVOID HwDeviceExtension, PI2C_CALLBACKS i2c, UCHAR Address)
-{
- /* setup lines for repeated start condition */
- WRITE_SCL(LOW);
- DELAY_HALF();
- WRITE_SDA(HIGH);
- DELAY_HALF();
- WRITE_SCL(HIGH);
- DELAY_HALF();
-
- return I2CStart(HwDeviceExtension, i2c, Address);
-}
-
-/* PUBLIC FUNCTIONS ***********************************************************/
-
-/*
- * @implemented
- */
-
-BOOLEAN NTAPI
-VideoPortDDCMonitorHelper(
- PVOID HwDeviceExtension,
- PVOID I2CFunctions,
- PUCHAR pEdidBuffer,
- ULONG EdidBufferSize
- )
-{
- PDDC_CONTROL ddc = (PDDC_CONTROL)I2CFunctions;
- PI2C_CALLBACKS i2c = &ddc->I2CCallbacks;
- INT Count, i;
- PUCHAR pBuffer = (PUCHAR)pEdidBuffer;
- BOOL Ack;
-
- TRACE_(VIDEOPRT, "VideoPortDDCMonitorHelper()\n");
-
- ASSERT_IRQL_LESS_OR_EQUAL(PASSIVE_LEVEL);
- if (ddc->Size != sizeof (ddc))
- {
- WARN_(VIDEOPRT, "ddc->Size != %d (%d)\n", sizeof (ddc), ddc->Size);
- return FALSE;
- }
-
- /* select eeprom */
- if (!I2CStart(HwDeviceExtension, i2c, DDC_EEPROM_ADDRESS | WRITE))
- return FALSE;
- /* set address */
- if (!I2CWrite(HwDeviceExtension, i2c, 0x00))
- return FALSE;
- /* change into read mode */
- if (!I2CRepStart(HwDeviceExtension, i2c, DDC_EEPROM_ADDRESS | READ))
- return FALSE;
- /* read eeprom */
- RtlZeroMemory(pEdidBuffer, EdidBufferSize);
- Count = min(128, EdidBufferSize);
- for (i = 0; i < Count; i++)
- {
- Ack = ((i + 1) < Count);
- pBuffer[i] = I2CRead(HwDeviceExtension, i2c, Ack);
- }
- I2CStop(HwDeviceExtension, i2c);
-
- /* check EDID header */
- if (pBuffer[0] != 0x00 || pBuffer[1] != 0xff ||
- pBuffer[2] != 0xff || pBuffer[3] != 0xff ||
- pBuffer[4] != 0xff || pBuffer[5] != 0xff ||
- pBuffer[6] != 0xff || pBuffer[7] != 0x00)
- {
- WARN_(VIDEOPRT, "VideoPortDDCMonitorHelper(): Invalid EDID header!\n");
- return FALSE;
- }
-
- INFO_(VIDEOPRT, "VideoPortDDCMonitorHelper(): EDID version %d rev. %d\n", pBuffer[18], pBuffer[19]);
- INFO_(VIDEOPRT, "VideoPortDDCMonitorHelper() - SUCCESS!\n");
- return TRUE;
-}
-
projects / reactos.git / blobdiff