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-rw-r--r--xorg-server/hw/xfree86/i2c/xf86i2c.c1745
1 files changed, 879 insertions, 866 deletions
diff --git a/xorg-server/hw/xfree86/i2c/xf86i2c.c b/xorg-server/hw/xfree86/i2c/xf86i2c.c
index 488b6815f..1273f4bab 100644
--- a/xorg-server/hw/xfree86/i2c/xf86i2c.c
+++ b/xorg-server/hw/xfree86/i2c/xf86i2c.c
@@ -1,866 +1,879 @@
-/*
- * Copyright (C) 1998 Itai Nahshon, Michael Schimek
- *
- * The original code was derived from and inspired by
- * the I2C driver from the Linux kernel.
- * (c) 1998 Gerd Knorr <kraxel@cs.tu-berlin.de>
- */
-
-
-#ifdef HAVE_XORG_CONFIG_H
-#include <xorg-config.h>
-#endif
-
-#include <sys/time.h>
-#include <string.h>
-
-#include "misc.h"
-#include "xf86.h"
-#include "xf86_OSproc.h"
-
-#include <X11/X.h>
-#include <X11/Xos.h>
-#include <X11/Xproto.h>
-#include "scrnintstr.h"
-#include "regionstr.h"
-#include "windowstr.h"
-#include "pixmapstr.h"
-#include "validate.h"
-#include "resource.h"
-#include "gcstruct.h"
-#include "dixstruct.h"
-
-#include "xf86i2c.h"
-
-#define I2C_TIMEOUT(x) /*(x)*/ /* Report timeouts */
-#define I2C_TRACE(x) /*(x)*/ /* Report progress */
-
-/* This is the default I2CUDelay function if not supplied by the driver.
- * High level I2C interfaces implementing the bus protocol in hardware
- * should supply this function too.
- *
- * Delay execution at least usec microseconds.
- * All values 0 to 1e6 inclusive must be expected.
- */
-
-static void
-I2CUDelay(I2CBusPtr b, int usec)
-{
- struct timeval begin, cur;
- long d_secs, d_usecs;
- long diff;
-
- if (usec > 0) {
- X_GETTIMEOFDAY(&begin);
- do {
- /* It would be nice to use {xf86}usleep,
- * but usleep (1) takes >10000 usec !
- */
- X_GETTIMEOFDAY(&cur);
- d_secs = (cur.tv_sec - begin.tv_sec);
- d_usecs = (cur.tv_usec - begin.tv_usec);
- diff = d_secs*1000000 + d_usecs;
- } while (diff>=0 && diff< (usec + 1));
- }
-}
-
-/* Most drivers will register just with GetBits/PutBits functions.
- * The following functions implement a software I2C protocol
- * by using the promitive functions given by the driver.
- * ================================================================
- *
- * It is assumed that there is just one master on the I2C bus, therefore
- * there is no explicit test for conflits.
- */
-
-#define RISEFALLTIME 2 /* usec, actually 300 to 1000 ns according to the i2c specs */
-
-/* Some devices will hold SCL low to slow down the bus or until
- * ready for transmission.
- *
- * This condition will be noticed when the master tries to raise
- * the SCL line. You can set the timeout to zero if the slave device
- * does not support this clock synchronization.
- */
-
-static Bool
-I2CRaiseSCL(I2CBusPtr b, int sda, int timeout)
-{
- int i, scl;
-
- b->I2CPutBits(b, 1, sda);
- b->I2CUDelay(b, b->RiseFallTime);
-
- for (i = timeout; i > 0; i -= b->RiseFallTime) {
- b->I2CGetBits(b, &scl, &sda);
- if (scl) break;
- b->I2CUDelay(b, b->RiseFallTime);
- }
-
- if (i <= 0) {
- I2C_TIMEOUT(ErrorF("[I2CRaiseSCL(<%s>, %d, %d) timeout]", b->BusName, sda, timeout));
- return FALSE;
- }
-
- return TRUE;
-}
-
-/* Send a start signal on the I2C bus. The start signal notifies
- * devices that a new transaction is initiated by the bus master.
- *
- * The start signal is always followed by a slave address.
- * Slave addresses are 8+ bits. The first 7 bits identify the
- * device and the last bit signals if this is a read (1) or
- * write (0) operation.
- *
- * There may be more than one start signal on one transaction.
- * This happens for example on some devices that allow reading
- * of registers. First send a start bit followed by the device
- * address (with the last bit 0) and the register number. Then send
- * a new start bit with the device address (with the last bit 1)
- * and then read the value from the device.
- *
- * Note this is function does not implement a multiple master
- * arbitration procedure.
- */
-
-static Bool
-I2CStart(I2CBusPtr b, int timeout)
-{
- if (!I2CRaiseSCL(b, 1, timeout))
- return FALSE;
-
- b->I2CPutBits(b, 1, 0);
- b->I2CUDelay(b, b->HoldTime);
- b->I2CPutBits(b, 0, 0);
- b->I2CUDelay(b, b->HoldTime);
-
- I2C_TRACE(ErrorF("\ni2c: <"));
-
- return TRUE;
-}
-
-/* This is the default I2CStop function if not supplied by the driver.
- *
- * Signal devices on the I2C bus that a transaction on the
- * bus has finished. There may be more than one start signal
- * on a transaction but only one stop signal.
- */
-
-static void
-I2CStop(I2CDevPtr d)
-{
- I2CBusPtr b = d->pI2CBus;
-
- b->I2CPutBits(b, 0, 0);
- b->I2CUDelay(b, b->RiseFallTime);
-
- b->I2CPutBits(b, 1, 0);
- b->I2CUDelay(b, b->HoldTime);
- b->I2CPutBits(b, 1, 1);
- b->I2CUDelay(b, b->HoldTime);
-
- I2C_TRACE(ErrorF(">\n"));
-}
-
-/* Write/Read a single bit to/from a device.
- * Return FALSE if a timeout occurs.
- */
-
-static Bool
-I2CWriteBit(I2CBusPtr b, int sda, int timeout)
-{
- Bool r;
-
- b->I2CPutBits(b, 0, sda);
- b->I2CUDelay(b, b->RiseFallTime);
-
- r = I2CRaiseSCL(b, sda, timeout);
- b->I2CUDelay(b, b->HoldTime);
-
- b->I2CPutBits(b, 0, sda);
- b->I2CUDelay(b, b->HoldTime);
-
- return r;
-}
-
-static Bool
-I2CReadBit(I2CBusPtr b, int *psda, int timeout)
-{
- Bool r;
- int scl;
-
- r = I2CRaiseSCL(b, 1, timeout);
- b->I2CUDelay(b, b->HoldTime);
-
- b->I2CGetBits(b, &scl, psda);
-
- b->I2CPutBits(b, 0, 1);
- b->I2CUDelay(b, b->HoldTime);
-
- return r;
-}
-
-/* This is the default I2CPutByte function if not supplied by the driver.
- *
- * A single byte is sent to the device.
- * The function returns FALSE if a timeout occurs, you should send
- * a stop condition afterwards to reset the bus.
- *
- * A timeout occurs,
- * if the slave pulls SCL to slow down the bus more than ByteTimeout usecs,
- * or slows down the bus for more than BitTimeout usecs for each bit,
- * or does not send an ACK bit (0) to acknowledge the transmission within
- * AcknTimeout usecs, but a NACK (1) bit.
- *
- * AcknTimeout must be at least b->HoldTime, the other timeouts can be
- * zero according to the comment on I2CRaiseSCL.
- */
-
-static Bool
-I2CPutByte(I2CDevPtr d, I2CByte data)
-{
- Bool r;
- int i, scl, sda;
- I2CBusPtr b = d->pI2CBus;
-
- if (!I2CWriteBit(b, (data >> 7) & 1, d->ByteTimeout))
- return FALSE;
-
- for (i = 6; i >= 0; i--)
- if (!I2CWriteBit(b, (data >> i) & 1, d->BitTimeout))
- return FALSE;
-
- b->I2CPutBits(b, 0, 1);
- b->I2CUDelay(b, b->RiseFallTime);
-
- r = I2CRaiseSCL(b, 1, b->HoldTime);
-
- if (r) {
- for (i = d->AcknTimeout; i > 0; i -= b->HoldTime) {
- b->I2CUDelay(b, b->HoldTime);
- b->I2CGetBits(b, &scl, &sda);
- if (sda == 0) break;
- }
-
- if (i <= 0) {
- I2C_TIMEOUT(ErrorF("[I2CPutByte(<%s>, 0x%02x, %d, %d, %d) timeout]",
- b->BusName, data, d->BitTimeout,
- d->ByteTimeout, d->AcknTimeout));
- r = FALSE;
- }
-
- I2C_TRACE(ErrorF("W%02x%c ", (int) data, sda ? '-' : '+'));
- }
-
- b->I2CPutBits(b, 0, 1);
- b->I2CUDelay(b, b->HoldTime);
-
- return r;
-}
-
-/* This is the default I2CGetByte function if not supplied by the driver.
- *
- * A single byte is read from the device.
- * The function returns FALSE if a timeout occurs, you should send
- * a stop condition afterwards to reset the bus.
- *
- * A timeout occurs,
- * if the slave pulls SCL to slow down the bus more than ByteTimeout usecs,
- * or slows down the bus for more than b->BitTimeout usecs for each bit.
- *
- * ByteTimeout must be at least b->HoldTime, the other timeouts can be
- * zero according to the comment on I2CRaiseSCL.
- *
- * For the <last> byte in a sequence the acknowledge bit NACK (1),
- * otherwise ACK (0) will be sent.
- */
-
-static Bool
-I2CGetByte(I2CDevPtr d, I2CByte *data, Bool last)
-{
- int i, sda;
- I2CBusPtr b = d->pI2CBus;
-
- b->I2CPutBits(b, 0, 1);
- b->I2CUDelay(b, b->RiseFallTime);
-
- if (!I2CReadBit(b, &sda, d->ByteTimeout))
- return FALSE;
-
- *data = (sda > 0) << 7;
-
- for (i = 6; i >= 0; i--)
- if (!I2CReadBit(b, &sda, d->BitTimeout))
- return FALSE;
- else
- *data |= (sda > 0) << i;
-
- if (!I2CWriteBit(b, last ? 1 : 0, d->BitTimeout))
- return FALSE;
-
- I2C_TRACE(ErrorF("R%02x%c ", (int) *data, last ? '+' : '-'));
-
- return TRUE;
-}
-
-/* This is the default I2CAddress function if not supplied by the driver.
- *
- * It creates the start condition, followed by the d->SlaveAddr.
- * Higher level functions must call this routine rather than
- * I2CStart/PutByte because a hardware I2C master may not be able
- * to send a slave address without a start condition.
- *
- * The same timeouts apply as with I2CPutByte and additional a
- * StartTimeout, similar to the ByteTimeout but for the start
- * condition.
- *
- * In case of a timeout, the bus is left in a clean idle condition.
- * I. e. you *must not* send a Stop. If this function succeeds, you *must*.
- *
- * The slave address format is 16 bit, with the legacy _8_bit_ slave address
- * in the least significant byte. This is, the slave address must include the
- * R/_W flag as least significant bit.
- *
- * The most significant byte of the address will be sent _after_ the LSB,
- * but only if the LSB indicates:
- * a) an 11 bit address, this is LSB = 1111 0xxx.
- * b) a 'general call address', this is LSB = 0000 000x - see the I2C specs
- * for more.
- */
-
-static Bool
-I2CAddress(I2CDevPtr d, I2CSlaveAddr addr)
-{
- if (I2CStart(d->pI2CBus, d->StartTimeout)) {
- if (I2CPutByte(d, addr & 0xFF)) {
- if ((addr & 0xF8) != 0xF0 &&
- (addr & 0xFE) != 0x00)
- return TRUE;
-
- if (I2CPutByte(d, (addr >> 8) & 0xFF))
- return TRUE;
- }
-
- I2CStop(d);
- }
-
- return FALSE;
-}
-
-/* These are the hardware independent I2C helper functions.
- * ========================================================
- */
-
-/* Function for probing. Just send the slave address
- * and return true if the device responds. The slave address
- * must have the lsb set to reflect a read (1) or write (0) access.
- * Don't expect a read- or write-only device will respond otherwise.
- */
-
-Bool
-xf86I2CProbeAddress(I2CBusPtr b, I2CSlaveAddr addr)
-{
- int r;
- I2CDevRec d;
-
- d.DevName = "Probing";
- d.BitTimeout = b->BitTimeout;
- d.ByteTimeout = b->ByteTimeout;
- d.AcknTimeout = b->AcknTimeout;
- d.StartTimeout = b->StartTimeout;
- d.SlaveAddr = addr;
- d.pI2CBus = b;
- d.NextDev = NULL;
-
- r = b->I2CAddress(&d, addr);
-
- if (r) b->I2CStop(&d);
-
- return r;
-}
-
-/* All functions below are related to devices and take the
- * slave address and timeout values from an I2CDevRec. They
- * return FALSE in case of an error (presumably a timeout).
- */
-
-/* General purpose read and write function.
- *
- * 1st, if nWrite > 0
- * Send a start condition
- * Send the slave address (1 or 2 bytes) with write flag
- * Write n bytes from WriteBuffer
- * 2nd, if nRead > 0
- * Send a start condition [again]
- * Send the slave address (1 or 2 bytes) with read flag
- * Read n bytes to ReadBuffer
- * 3rd, if a Start condition has been successfully sent,
- * Send a Stop condition.
- *
- * The functions exits immediately when an error occures,
- * not proceeding any data left. However, step 3 will
- * be executed anyway to leave the bus in clean idle state.
- */
-
-static Bool
-I2CWriteRead(I2CDevPtr d,
- I2CByte *WriteBuffer, int nWrite,
- I2CByte *ReadBuffer, int nRead)
-{
- Bool r = TRUE;
- I2CBusPtr b = d->pI2CBus;
- int s = 0;
-
- if (r && nWrite > 0) {
- r = b->I2CAddress(d, d->SlaveAddr & ~1);
- if (r) {
- for (; nWrite > 0; WriteBuffer++, nWrite--)
- if (!(r = b->I2CPutByte(d, *WriteBuffer)))
- break;
- s++;
- }
- }
-
- if (r && nRead > 0) {
- r = b->I2CAddress(d, d->SlaveAddr | 1);
- if (r) {
- for (; nRead > 0; ReadBuffer++, nRead--)
- if (!(r = b->I2CGetByte(d, ReadBuffer, nRead == 1)))
- break;
- s++;
- }
- }
-
- if (s) b->I2CStop(d);
-
- return r;
-}
-
-/* wrapper - for compatibility and convinience */
-
-Bool
-xf86I2CWriteRead(I2CDevPtr d,
- I2CByte *WriteBuffer, int nWrite,
- I2CByte *ReadBuffer, int nRead)
-{
- I2CBusPtr b = d->pI2CBus;
- return b->I2CWriteRead(d,WriteBuffer,nWrite,ReadBuffer,nRead);
-}
-
-/* Read a byte, the only readable register of a device.
- */
-
-Bool
-xf86I2CReadStatus(I2CDevPtr d, I2CByte *pbyte)
-{
- return xf86I2CWriteRead(d, NULL, 0, pbyte, 1);
-}
-
-/* Read a byte from one of the registers determined by its sub-address.
- */
-
-Bool
-xf86I2CReadByte(I2CDevPtr d, I2CByte subaddr, I2CByte *pbyte)
-{
- return xf86I2CWriteRead(d, &subaddr, 1, pbyte, 1);
-}
-
-/* Read bytes from subsequent registers determined by the
- * sub-address of the first register.
- */
-
-Bool
-xf86I2CReadBytes(I2CDevPtr d, I2CByte subaddr, I2CByte *pbyte, int n)
-{
- return xf86I2CWriteRead(d, &subaddr, 1, pbyte, n);
-}
-
-/* Read a word (high byte, then low byte) from one of the registers
- * determined by its sub-address.
- */
-
-Bool
-xf86I2CReadWord(I2CDevPtr d, I2CByte subaddr, unsigned short *pword)
-{
- I2CByte rb[2];
-
- if (!xf86I2CWriteRead(d, &subaddr, 1, rb, 2)) return FALSE;
-
- *pword = (rb[0] << 8) | rb[1];
-
- return TRUE;
-}
-
-/* Write a byte to one of the registers determined by its sub-address.
- */
-
-Bool
-xf86I2CWriteByte(I2CDevPtr d, I2CByte subaddr, I2CByte byte)
-{
- I2CByte wb[2];
-
- wb[0] = subaddr;
- wb[1] = byte;
-
- return xf86I2CWriteRead(d, wb, 2, NULL, 0);
-}
-
-/* Write bytes to subsequent registers determined by the
- * sub-address of the first register.
- */
-
-Bool
-xf86I2CWriteBytes(I2CDevPtr d, I2CByte subaddr,
- I2CByte *WriteBuffer, int nWrite)
-{
- I2CBusPtr b = d->pI2CBus;
- Bool r = TRUE;
-
- if (nWrite > 0) {
- r = b->I2CAddress(d, d->SlaveAddr & ~1);
- if (r){
- if ((r = b->I2CPutByte(d, subaddr)))
- for (; nWrite > 0; WriteBuffer++, nWrite--)
- if (!(r = b->I2CPutByte(d, *WriteBuffer)))
- break;
-
- b->I2CStop(d);
- }
- }
-
- return r;
-}
-
-/* Write a word (high byte, then low byte) to one of the registers
- * determined by its sub-address.
- */
-
-Bool
-xf86I2CWriteWord(I2CDevPtr d, I2CByte subaddr, unsigned short word)
-{
- I2CByte wb[3];
-
- wb[0] = subaddr;
- wb[1] = word >> 8;
- wb[2] = word & 0xFF;
-
- return xf86I2CWriteRead(d, wb, 3, NULL, 0);
-}
-
-/* Write a vector of bytes to not adjacent registers. This vector is,
- * 1st byte sub-address, 2nd byte value, 3rd byte sub-address asf.
- * This function is intended to initialize devices. Note this function
- * exits immediately when an error occurs, some registers may
- * remain uninitialized.
- */
-
-Bool
-xf86I2CWriteVec(I2CDevPtr d, I2CByte *vec, int nValues)
-{
- I2CBusPtr b = d->pI2CBus;
- Bool r = TRUE;
- int s = 0;
-
- if (nValues > 0) {
- for (; nValues > 0; nValues--, vec += 2) {
- if (!(r = b->I2CAddress(d, d->SlaveAddr & ~1)))
- break;
-
- s++;
-
- if (!(r = b->I2CPutByte(d, vec[0])))
- break;
-
- if (!(r = b->I2CPutByte(d, vec[1])))
- break;
- }
-
- if (s > 0) b->I2CStop(d);
- }
-
- return r;
-}
-
-/* Administrative functions.
- * =========================
- */
-
-/* Allocates an I2CDevRec for you and initializes with propper defaults
- * you may modify before calling xf86I2CDevInit. Your I2CDevRec must
- * contain at least a SlaveAddr, and a pI2CBus pointer to the bus this
- * device shall be linked to.
- *
- * See function I2CAddress for the slave address format. Always set
- * the least significant bit, indicating a read or write access, to zero.
- */
-
-I2CDevPtr
-xf86CreateI2CDevRec(void)
-{
- return calloc(1, sizeof(I2CDevRec));
-}
-
-/* Unlink an I2C device. If you got the I2CDevRec from xf86CreateI2CDevRec
- * you should set <unalloc> to free it.
- */
-
-void
-xf86DestroyI2CDevRec(I2CDevPtr d, Bool unalloc)
-{
- if (d) {
- I2CDevPtr *p;
-
- /* Remove this from the list of active I2C devices. */
-
- for (p = &d->pI2CBus->FirstDev; *p != NULL; p = &(*p)->NextDev)
- if (*p == d) {
- *p = (*p)->NextDev;
- break;
- }
-
- xf86DrvMsg(d->pI2CBus->scrnIndex, X_INFO,
- "I2C device \"%s:%s\" removed.\n",
- d->pI2CBus->BusName, d->DevName);
-
- if (unalloc) free(d);
- }
-}
-
-/* I2C transmissions are related to an I2CDevRec you must link to a
- * previously registered bus (see xf86I2CBusInit) before attempting
- * to read and write data. You may call xf86I2CProbeAddress first to
- * see if the device in question is present on this bus.
- *
- * xf86I2CDevInit will not allocate an I2CBusRec for you, instead you
- * may enter a pointer to a statically allocated I2CDevRec or the (modified)
- * result of xf86CreateI2CDevRec.
- *
- * If you don't specify timeouts for the device (n <= 0), it will inherit
- * the bus-wide defaults. The function returns TRUE on success.
- */
-
-Bool
-xf86I2CDevInit(I2CDevPtr d)
-{
- I2CBusPtr b;
-
- if (d == NULL ||
- (b = d->pI2CBus) == NULL ||
- (d->SlaveAddr & 1) ||
- xf86I2CFindDev(b, d->SlaveAddr) != NULL)
- return FALSE;
-
- if (d->BitTimeout <= 0) d->BitTimeout = b->BitTimeout;
- if (d->ByteTimeout <= 0) d->ByteTimeout = b->ByteTimeout;
- if (d->AcknTimeout <= 0) d->AcknTimeout = b->AcknTimeout;
- if (d->StartTimeout <= 0) d->StartTimeout = b->StartTimeout;
-
- d->NextDev = b->FirstDev;
- b->FirstDev = d;
-
- xf86DrvMsg(b->scrnIndex, X_INFO,
- "I2C device \"%s:%s\" registered at address 0x%02X.\n",
- b->BusName, d->DevName, d->SlaveAddr);
-
- return TRUE;
-}
-
-I2CDevPtr
-xf86I2CFindDev(I2CBusPtr b, I2CSlaveAddr addr)
-{
- I2CDevPtr d;
-
- if (b) {
- for (d = b->FirstDev; d != NULL; d = d->NextDev)
- if (d->SlaveAddr == addr)
- return d;
- }
-
- return NULL;
-}
-
-static I2CBusPtr I2CBusList;
-
-/* Allocates an I2CBusRec for you and initializes with propper defaults
- * you may modify before calling xf86I2CBusInit. Your I2CBusRec must
- * contain at least a BusName, a scrnIndex (or -1), and a complete set
- * of either high or low level I2C function pointers. You may pass
- * bus-wide timeouts, otherwise inplausible values will be replaced
- * with safe defaults.
- */
-
-I2CBusPtr
-xf86CreateI2CBusRec(void)
-{
- I2CBusPtr b;
-
- b = (I2CBusPtr) calloc(1, sizeof(I2CBusRec));
-
- if (b != NULL) {
- b->scrnIndex = -1;
- b->HoldTime = 5; /* 100 kHz bus */
- b->BitTimeout = 5;
- b->ByteTimeout = 5;
- b->AcknTimeout = 5;
- b->StartTimeout = 5;
- b->RiseFallTime = RISEFALLTIME;
- }
-
- return b;
-}
-
-/* Unregister an I2C bus. If you got the I2CBusRec from xf86CreateI2CBusRec
- * you should set <unalloc> to free it. If you set <devs_too>, the function
- * xf86DestroyI2CDevRec will be called for all devices linked to the bus
- * first, passing down the <unalloc> option.
- */
-
-void
-xf86DestroyI2CBusRec(I2CBusPtr b, Bool unalloc, Bool devs_too)
-{
- if (b) {
- I2CBusPtr *p;
-
- /* Remove this from the list of active I2C buses */
-
- for (p = &I2CBusList; *p != NULL; p = &(*p)->NextBus)
- if (*p == b) {
- *p = (*p)->NextBus;
- break;
- }
-
- if (b->FirstDev != NULL) {
- if (devs_too) {
- I2CDevPtr d;
-
- while ((d = b->FirstDev) != NULL) {
- b->FirstDev = d->NextDev;
- xf86DestroyI2CDevRec(d, unalloc);
- }
- } else {
- if (unalloc) {
- xf86Msg(X_ERROR, "i2c bug: Attempt to remove I2C bus \"%s\", "
- "but device list is not empty.\n",
- b->BusName);
- return;
- }
- }
- }
-
- xf86DrvMsg(b->scrnIndex, X_INFO, "I2C bus \"%s\" removed.\n",
- b->BusName);
-
- if (unalloc) free(b);
- }
-}
-
-/* I2C masters have to register themselves using this function.
- * It will not allocate an I2CBusRec for you, instead you may enter
- * a pointer to a statically allocated I2CBusRec or the (modified)
- * result of xf86CreateI2CBusRec. Returns TRUE on success.
- *
- * At this point there won't be any traffic on the I2C bus.
- */
-
-Bool
-xf86I2CBusInit(I2CBusPtr b)
-{
- /* I2C buses must be identified by a unique scrnIndex
- * and name. If scrnIndex is unspecified (a negative value),
- * then the name must be unique throughout the server.
- */
-
- if (b->BusName == NULL ||
- xf86I2CFindBus(b->scrnIndex, b->BusName) != NULL)
- return FALSE;
-
- /* If the high level functions are not
- * supplied, use the generic functions.
- * In this case we need the low-level
- * function.
- */
- if (b->I2CWriteRead == NULL)
- {
- b->I2CWriteRead=I2CWriteRead;
-
- if (b->I2CPutBits == NULL ||
- b->I2CGetBits == NULL)
- {
- if (b->I2CPutByte == NULL ||
- b->I2CGetByte == NULL ||
- b->I2CAddress == NULL ||
- b->I2CStart == NULL ||
- b->I2CStop == NULL)
- return FALSE;
- } else {
- b->I2CPutByte = I2CPutByte;
- b->I2CGetByte = I2CGetByte;
- b->I2CAddress = I2CAddress;
- b->I2CStop = I2CStop;
- b->I2CStart = I2CStart;
- }
- }
-
- if (b->I2CUDelay == NULL)
- b->I2CUDelay = I2CUDelay;
-
- if (b->HoldTime < 2) b->HoldTime = 5;
- if (b->BitTimeout <= 0) b->BitTimeout = b->HoldTime;
- if (b->ByteTimeout <= 0) b->ByteTimeout = b->HoldTime;
- if (b->AcknTimeout <= 0) b->AcknTimeout = b->HoldTime;
- if (b->StartTimeout <= 0) b->StartTimeout = b->HoldTime;
-
- /* Put new bus on list. */
-
- b->NextBus = I2CBusList;
- I2CBusList = b;
-
- xf86DrvMsg(b->scrnIndex, X_INFO, "I2C bus \"%s\" initialized.\n",
- b->BusName);
-
- return TRUE;
-}
-
-I2CBusPtr
-xf86I2CFindBus(int scrnIndex, char *name)
-{
- I2CBusPtr p;
-
- if (name != NULL)
- for (p = I2CBusList; p != NULL; p = p->NextBus)
- if (scrnIndex < 0 || p->scrnIndex == scrnIndex)
- if (!strcmp(p->BusName, name))
- return p;
-
- return NULL;
-}
-
-/*
- * Return an array of I2CBusPtr's related to a screen. The caller is
- * responsible for freeing the array.
- */
-int
-xf86I2CGetScreenBuses(int scrnIndex, I2CBusPtr **pppI2CBus)
-{
- I2CBusPtr pI2CBus;
- int n = 0;
-
- if (pppI2CBus)
- *pppI2CBus = NULL;
-
- for (pI2CBus = I2CBusList; pI2CBus; pI2CBus = pI2CBus->NextBus) {
- if ((pI2CBus->scrnIndex >= 0) && (pI2CBus->scrnIndex != scrnIndex))
- continue;
-
- n++;
-
- if (!pppI2CBus)
- continue;
-
- *pppI2CBus = xnfrealloc(*pppI2CBus, n * sizeof(I2CBusPtr));
- (*pppI2CBus)[n - 1] = pI2CBus;
- }
-
- return n;
-}
+/*
+ * Copyright (C) 1998 Itai Nahshon, Michael Schimek
+ *
+ * The original code was derived from and inspired by
+ * the I2C driver from the Linux kernel.
+ * (c) 1998 Gerd Knorr <kraxel@cs.tu-berlin.de>
+ */
+
+#ifdef HAVE_XORG_CONFIG_H
+#include <xorg-config.h>
+#endif
+
+#include <sys/time.h>
+#include <string.h>
+
+#include "misc.h"
+#include "xf86.h"
+#include "xf86_OSproc.h"
+
+#include <X11/X.h>
+#include <X11/Xos.h>
+#include <X11/Xproto.h>
+#include "scrnintstr.h"
+#include "regionstr.h"
+#include "windowstr.h"
+#include "pixmapstr.h"
+#include "validate.h"
+#include "resource.h"
+#include "gcstruct.h"
+#include "dixstruct.h"
+
+#include "xf86i2c.h"
+
+#define I2C_TIMEOUT(x) /*(x)*/ /* Report timeouts */
+#define I2C_TRACE(x) /*(x)*/ /* Report progress */
+
+/* This is the default I2CUDelay function if not supplied by the driver.
+ * High level I2C interfaces implementing the bus protocol in hardware
+ * should supply this function too.
+ *
+ * Delay execution at least usec microseconds.
+ * All values 0 to 1e6 inclusive must be expected.
+ */
+
+static void
+I2CUDelay(I2CBusPtr b, int usec)
+{
+ struct timeval begin, cur;
+ long d_secs, d_usecs;
+ long diff;
+
+ if (usec > 0) {
+ X_GETTIMEOFDAY(&begin);
+ do {
+ /* It would be nice to use {xf86}usleep,
+ * but usleep (1) takes >10000 usec !
+ */
+ X_GETTIMEOFDAY(&cur);
+ d_secs = (cur.tv_sec - begin.tv_sec);
+ d_usecs = (cur.tv_usec - begin.tv_usec);
+ diff = d_secs * 1000000 + d_usecs;
+ } while (diff >= 0 && diff < (usec + 1));
+ }
+}
+
+/* Most drivers will register just with GetBits/PutBits functions.
+ * The following functions implement a software I2C protocol
+ * by using the promitive functions given by the driver.
+ * ================================================================
+ *
+ * It is assumed that there is just one master on the I2C bus, therefore
+ * there is no explicit test for conflits.
+ */
+
+#define RISEFALLTIME 2 /* usec, actually 300 to 1000 ns according to the i2c specs */
+
+/* Some devices will hold SCL low to slow down the bus or until
+ * ready for transmission.
+ *
+ * This condition will be noticed when the master tries to raise
+ * the SCL line. You can set the timeout to zero if the slave device
+ * does not support this clock synchronization.
+ */
+
+static Bool
+I2CRaiseSCL(I2CBusPtr b, int sda, int timeout)
+{
+ int i, scl;
+
+ b->I2CPutBits(b, 1, sda);
+ b->I2CUDelay(b, b->RiseFallTime);
+
+ for (i = timeout; i > 0; i -= b->RiseFallTime) {
+ b->I2CGetBits(b, &scl, &sda);
+ if (scl)
+ break;
+ b->I2CUDelay(b, b->RiseFallTime);
+ }
+
+ if (i <= 0) {
+ I2C_TIMEOUT(ErrorF
+ ("[I2CRaiseSCL(<%s>, %d, %d) timeout]", b->BusName, sda,
+ timeout));
+ return FALSE;
+ }
+
+ return TRUE;
+}
+
+/* Send a start signal on the I2C bus. The start signal notifies
+ * devices that a new transaction is initiated by the bus master.
+ *
+ * The start signal is always followed by a slave address.
+ * Slave addresses are 8+ bits. The first 7 bits identify the
+ * device and the last bit signals if this is a read (1) or
+ * write (0) operation.
+ *
+ * There may be more than one start signal on one transaction.
+ * This happens for example on some devices that allow reading
+ * of registers. First send a start bit followed by the device
+ * address (with the last bit 0) and the register number. Then send
+ * a new start bit with the device address (with the last bit 1)
+ * and then read the value from the device.
+ *
+ * Note this is function does not implement a multiple master
+ * arbitration procedure.
+ */
+
+static Bool
+I2CStart(I2CBusPtr b, int timeout)
+{
+ if (!I2CRaiseSCL(b, 1, timeout))
+ return FALSE;
+
+ b->I2CPutBits(b, 1, 0);
+ b->I2CUDelay(b, b->HoldTime);
+ b->I2CPutBits(b, 0, 0);
+ b->I2CUDelay(b, b->HoldTime);
+
+ I2C_TRACE(ErrorF("\ni2c: <"));
+
+ return TRUE;
+}
+
+/* This is the default I2CStop function if not supplied by the driver.
+ *
+ * Signal devices on the I2C bus that a transaction on the
+ * bus has finished. There may be more than one start signal
+ * on a transaction but only one stop signal.
+ */
+
+static void
+I2CStop(I2CDevPtr d)
+{
+ I2CBusPtr b = d->pI2CBus;
+
+ b->I2CPutBits(b, 0, 0);
+ b->I2CUDelay(b, b->RiseFallTime);
+
+ b->I2CPutBits(b, 1, 0);
+ b->I2CUDelay(b, b->HoldTime);
+ b->I2CPutBits(b, 1, 1);
+ b->I2CUDelay(b, b->HoldTime);
+
+ I2C_TRACE(ErrorF(">\n"));
+}
+
+/* Write/Read a single bit to/from a device.
+ * Return FALSE if a timeout occurs.
+ */
+
+static Bool
+I2CWriteBit(I2CBusPtr b, int sda, int timeout)
+{
+ Bool r;
+
+ b->I2CPutBits(b, 0, sda);
+ b->I2CUDelay(b, b->RiseFallTime);
+
+ r = I2CRaiseSCL(b, sda, timeout);
+ b->I2CUDelay(b, b->HoldTime);
+
+ b->I2CPutBits(b, 0, sda);
+ b->I2CUDelay(b, b->HoldTime);
+
+ return r;
+}
+
+static Bool
+I2CReadBit(I2CBusPtr b, int *psda, int timeout)
+{
+ Bool r;
+ int scl;
+
+ r = I2CRaiseSCL(b, 1, timeout);
+ b->I2CUDelay(b, b->HoldTime);
+
+ b->I2CGetBits(b, &scl, psda);
+
+ b->I2CPutBits(b, 0, 1);
+ b->I2CUDelay(b, b->HoldTime);
+
+ return r;
+}
+
+/* This is the default I2CPutByte function if not supplied by the driver.
+ *
+ * A single byte is sent to the device.
+ * The function returns FALSE if a timeout occurs, you should send
+ * a stop condition afterwards to reset the bus.
+ *
+ * A timeout occurs,
+ * if the slave pulls SCL to slow down the bus more than ByteTimeout usecs,
+ * or slows down the bus for more than BitTimeout usecs for each bit,
+ * or does not send an ACK bit (0) to acknowledge the transmission within
+ * AcknTimeout usecs, but a NACK (1) bit.
+ *
+ * AcknTimeout must be at least b->HoldTime, the other timeouts can be
+ * zero according to the comment on I2CRaiseSCL.
+ */
+
+static Bool
+I2CPutByte(I2CDevPtr d, I2CByte data)
+{
+ Bool r;
+ int i, scl, sda;
+ I2CBusPtr b = d->pI2CBus;
+
+ if (!I2CWriteBit(b, (data >> 7) & 1, d->ByteTimeout))
+ return FALSE;
+
+ for (i = 6; i >= 0; i--)
+ if (!I2CWriteBit(b, (data >> i) & 1, d->BitTimeout))
+ return FALSE;
+
+ b->I2CPutBits(b, 0, 1);
+ b->I2CUDelay(b, b->RiseFallTime);
+
+ r = I2CRaiseSCL(b, 1, b->HoldTime);
+
+ if (r) {
+ for (i = d->AcknTimeout; i > 0; i -= b->HoldTime) {
+ b->I2CUDelay(b, b->HoldTime);
+ b->I2CGetBits(b, &scl, &sda);
+ if (sda == 0)
+ break;
+ }
+
+ if (i <= 0) {
+ I2C_TIMEOUT(ErrorF("[I2CPutByte(<%s>, 0x%02x, %d, %d, %d) timeout]",
+ b->BusName, data, d->BitTimeout,
+ d->ByteTimeout, d->AcknTimeout));
+ r = FALSE;
+ }
+
+ I2C_TRACE(ErrorF("W%02x%c ", (int) data, sda ? '-' : '+'));
+ }
+
+ b->I2CPutBits(b, 0, 1);
+ b->I2CUDelay(b, b->HoldTime);
+
+ return r;
+}
+
+/* This is the default I2CGetByte function if not supplied by the driver.
+ *
+ * A single byte is read from the device.
+ * The function returns FALSE if a timeout occurs, you should send
+ * a stop condition afterwards to reset the bus.
+ *
+ * A timeout occurs,
+ * if the slave pulls SCL to slow down the bus more than ByteTimeout usecs,
+ * or slows down the bus for more than b->BitTimeout usecs for each bit.
+ *
+ * ByteTimeout must be at least b->HoldTime, the other timeouts can be
+ * zero according to the comment on I2CRaiseSCL.
+ *
+ * For the <last> byte in a sequence the acknowledge bit NACK (1),
+ * otherwise ACK (0) will be sent.
+ */
+
+static Bool
+I2CGetByte(I2CDevPtr d, I2CByte * data, Bool last)
+{
+ int i, sda;
+ I2CBusPtr b = d->pI2CBus;
+
+ b->I2CPutBits(b, 0, 1);
+ b->I2CUDelay(b, b->RiseFallTime);
+
+ if (!I2CReadBit(b, &sda, d->ByteTimeout))
+ return FALSE;
+
+ *data = (sda > 0) << 7;
+
+ for (i = 6; i >= 0; i--)
+ if (!I2CReadBit(b, &sda, d->BitTimeout))
+ return FALSE;
+ else
+ *data |= (sda > 0) << i;
+
+ if (!I2CWriteBit(b, last ? 1 : 0, d->BitTimeout))
+ return FALSE;
+
+ I2C_TRACE(ErrorF("R%02x%c ", (int) *data, last ? '+' : '-'));
+
+ return TRUE;
+}
+
+/* This is the default I2CAddress function if not supplied by the driver.
+ *
+ * It creates the start condition, followed by the d->SlaveAddr.
+ * Higher level functions must call this routine rather than
+ * I2CStart/PutByte because a hardware I2C master may not be able
+ * to send a slave address without a start condition.
+ *
+ * The same timeouts apply as with I2CPutByte and additional a
+ * StartTimeout, similar to the ByteTimeout but for the start
+ * condition.
+ *
+ * In case of a timeout, the bus is left in a clean idle condition.
+ * I. e. you *must not* send a Stop. If this function succeeds, you *must*.
+ *
+ * The slave address format is 16 bit, with the legacy _8_bit_ slave address
+ * in the least significant byte. This is, the slave address must include the
+ * R/_W flag as least significant bit.
+ *
+ * The most significant byte of the address will be sent _after_ the LSB,
+ * but only if the LSB indicates:
+ * a) an 11 bit address, this is LSB = 1111 0xxx.
+ * b) a 'general call address', this is LSB = 0000 000x - see the I2C specs
+ * for more.
+ */
+
+static Bool
+I2CAddress(I2CDevPtr d, I2CSlaveAddr addr)
+{
+ if (I2CStart(d->pI2CBus, d->StartTimeout)) {
+ if (I2CPutByte(d, addr & 0xFF)) {
+ if ((addr & 0xF8) != 0xF0 && (addr & 0xFE) != 0x00)
+ return TRUE;
+
+ if (I2CPutByte(d, (addr >> 8) & 0xFF))
+ return TRUE;
+ }
+
+ I2CStop(d);
+ }
+
+ return FALSE;
+}
+
+/* These are the hardware independent I2C helper functions.
+ * ========================================================
+ */
+
+/* Function for probing. Just send the slave address
+ * and return true if the device responds. The slave address
+ * must have the lsb set to reflect a read (1) or write (0) access.
+ * Don't expect a read- or write-only device will respond otherwise.
+ */
+
+Bool
+xf86I2CProbeAddress(I2CBusPtr b, I2CSlaveAddr addr)
+{
+ int r;
+ I2CDevRec d;
+
+ d.DevName = "Probing";
+ d.BitTimeout = b->BitTimeout;
+ d.ByteTimeout = b->ByteTimeout;
+ d.AcknTimeout = b->AcknTimeout;
+ d.StartTimeout = b->StartTimeout;
+ d.SlaveAddr = addr;
+ d.pI2CBus = b;
+ d.NextDev = NULL;
+
+ r = b->I2CAddress(&d, addr);
+
+ if (r)
+ b->I2CStop(&d);
+
+ return r;
+}
+
+/* All functions below are related to devices and take the
+ * slave address and timeout values from an I2CDevRec. They
+ * return FALSE in case of an error (presumably a timeout).
+ */
+
+/* General purpose read and write function.
+ *
+ * 1st, if nWrite > 0
+ * Send a start condition
+ * Send the slave address (1 or 2 bytes) with write flag
+ * Write n bytes from WriteBuffer
+ * 2nd, if nRead > 0
+ * Send a start condition [again]
+ * Send the slave address (1 or 2 bytes) with read flag
+ * Read n bytes to ReadBuffer
+ * 3rd, if a Start condition has been successfully sent,
+ * Send a Stop condition.
+ *
+ * The functions exits immediately when an error occures,
+ * not proceeding any data left. However, step 3 will
+ * be executed anyway to leave the bus in clean idle state.
+ */
+
+static Bool
+I2CWriteRead(I2CDevPtr d,
+ I2CByte * WriteBuffer, int nWrite, I2CByte * ReadBuffer, int nRead)
+{
+ Bool r = TRUE;
+ I2CBusPtr b = d->pI2CBus;
+ int s = 0;
+
+ if (r && nWrite > 0) {
+ r = b->I2CAddress(d, d->SlaveAddr & ~1);
+ if (r) {
+ for (; nWrite > 0; WriteBuffer++, nWrite--)
+ if (!(r = b->I2CPutByte(d, *WriteBuffer)))
+ break;
+ s++;
+ }
+ }
+
+ if (r && nRead > 0) {
+ r = b->I2CAddress(d, d->SlaveAddr | 1);
+ if (r) {
+ for (; nRead > 0; ReadBuffer++, nRead--)
+ if (!(r = b->I2CGetByte(d, ReadBuffer, nRead == 1)))
+ break;
+ s++;
+ }
+ }
+
+ if (s)
+ b->I2CStop(d);
+
+ return r;
+}
+
+/* wrapper - for compatibility and convinience */
+
+Bool
+xf86I2CWriteRead(I2CDevPtr d,
+ I2CByte * WriteBuffer, int nWrite,
+ I2CByte * ReadBuffer, int nRead)
+{
+ I2CBusPtr b = d->pI2CBus;
+
+ return b->I2CWriteRead(d, WriteBuffer, nWrite, ReadBuffer, nRead);
+}
+
+/* Read a byte, the only readable register of a device.
+ */
+
+Bool
+xf86I2CReadStatus(I2CDevPtr d, I2CByte * pbyte)
+{
+ return xf86I2CWriteRead(d, NULL, 0, pbyte, 1);
+}
+
+/* Read a byte from one of the registers determined by its sub-address.
+ */
+
+Bool
+xf86I2CReadByte(I2CDevPtr d, I2CByte subaddr, I2CByte * pbyte)
+{
+ return xf86I2CWriteRead(d, &subaddr, 1, pbyte, 1);
+}
+
+/* Read bytes from subsequent registers determined by the
+ * sub-address of the first register.
+ */
+
+Bool
+xf86I2CReadBytes(I2CDevPtr d, I2CByte subaddr, I2CByte * pbyte, int n)
+{
+ return xf86I2CWriteRead(d, &subaddr, 1, pbyte, n);
+}
+
+/* Read a word (high byte, then low byte) from one of the registers
+ * determined by its sub-address.
+ */
+
+Bool
+xf86I2CReadWord(I2CDevPtr d, I2CByte subaddr, unsigned short *pword)
+{
+ I2CByte rb[2];
+
+ if (!xf86I2CWriteRead(d, &subaddr, 1, rb, 2))
+ return FALSE;
+
+ *pword = (rb[0] << 8) | rb[1];
+
+ return TRUE;
+}
+
+/* Write a byte to one of the registers determined by its sub-address.
+ */
+
+Bool
+xf86I2CWriteByte(I2CDevPtr d, I2CByte subaddr, I2CByte byte)
+{
+ I2CByte wb[2];
+
+ wb[0] = subaddr;
+ wb[1] = byte;
+
+ return xf86I2CWriteRead(d, wb, 2, NULL, 0);
+}
+
+/* Write bytes to subsequent registers determined by the
+ * sub-address of the first register.
+ */
+
+Bool
+xf86I2CWriteBytes(I2CDevPtr d, I2CByte subaddr,
+ I2CByte * WriteBuffer, int nWrite)
+{
+ I2CBusPtr b = d->pI2CBus;
+ Bool r = TRUE;
+
+ if (nWrite > 0) {
+ r = b->I2CAddress(d, d->SlaveAddr & ~1);
+ if (r) {
+ if ((r = b->I2CPutByte(d, subaddr)))
+ for (; nWrite > 0; WriteBuffer++, nWrite--)
+ if (!(r = b->I2CPutByte(d, *WriteBuffer)))
+ break;
+
+ b->I2CStop(d);
+ }
+ }
+
+ return r;
+}
+
+/* Write a word (high byte, then low byte) to one of the registers
+ * determined by its sub-address.
+ */
+
+Bool
+xf86I2CWriteWord(I2CDevPtr d, I2CByte subaddr, unsigned short word)
+{
+ I2CByte wb[3];
+
+ wb[0] = subaddr;
+ wb[1] = word >> 8;
+ wb[2] = word & 0xFF;
+
+ return xf86I2CWriteRead(d, wb, 3, NULL, 0);
+}
+
+/* Write a vector of bytes to not adjacent registers. This vector is,
+ * 1st byte sub-address, 2nd byte value, 3rd byte sub-address asf.
+ * This function is intended to initialize devices. Note this function
+ * exits immediately when an error occurs, some registers may
+ * remain uninitialized.
+ */
+
+Bool
+xf86I2CWriteVec(I2CDevPtr d, I2CByte * vec, int nValues)
+{
+ I2CBusPtr b = d->pI2CBus;
+ Bool r = TRUE;
+ int s = 0;
+
+ if (nValues > 0) {
+ for (; nValues > 0; nValues--, vec += 2) {
+ if (!(r = b->I2CAddress(d, d->SlaveAddr & ~1)))
+ break;
+
+ s++;
+
+ if (!(r = b->I2CPutByte(d, vec[0])))
+ break;
+
+ if (!(r = b->I2CPutByte(d, vec[1])))
+ break;
+ }
+
+ if (s > 0)
+ b->I2CStop(d);
+ }
+
+ return r;
+}
+
+/* Administrative functions.
+ * =========================
+ */
+
+/* Allocates an I2CDevRec for you and initializes with propper defaults
+ * you may modify before calling xf86I2CDevInit. Your I2CDevRec must
+ * contain at least a SlaveAddr, and a pI2CBus pointer to the bus this
+ * device shall be linked to.
+ *
+ * See function I2CAddress for the slave address format. Always set
+ * the least significant bit, indicating a read or write access, to zero.
+ */
+
+I2CDevPtr
+xf86CreateI2CDevRec(void)
+{
+ return calloc(1, sizeof(I2CDevRec));
+}
+
+/* Unlink an I2C device. If you got the I2CDevRec from xf86CreateI2CDevRec
+ * you should set <unalloc> to free it.
+ */
+
+void
+xf86DestroyI2CDevRec(I2CDevPtr d, Bool unalloc)
+{
+ if (d) {
+ I2CDevPtr *p;
+
+ /* Remove this from the list of active I2C devices. */
+
+ for (p = &d->pI2CBus->FirstDev; *p != NULL; p = &(*p)->NextDev)
+ if (*p == d) {
+ *p = (*p)->NextDev;
+ break;
+ }
+
+ xf86DrvMsg(d->pI2CBus->scrnIndex, X_INFO,
+ "I2C device \"%s:%s\" removed.\n",
+ d->pI2CBus->BusName, d->DevName);
+
+ if (unalloc)
+ free(d);
+ }
+}
+
+/* I2C transmissions are related to an I2CDevRec you must link to a
+ * previously registered bus (see xf86I2CBusInit) before attempting
+ * to read and write data. You may call xf86I2CProbeAddress first to
+ * see if the device in question is present on this bus.
+ *
+ * xf86I2CDevInit will not allocate an I2CBusRec for you, instead you
+ * may enter a pointer to a statically allocated I2CDevRec or the (modified)
+ * result of xf86CreateI2CDevRec.
+ *
+ * If you don't specify timeouts for the device (n <= 0), it will inherit
+ * the bus-wide defaults. The function returns TRUE on success.
+ */
+
+Bool
+xf86I2CDevInit(I2CDevPtr d)
+{
+ I2CBusPtr b;
+
+ if (d == NULL ||
+ (b = d->pI2CBus) == NULL ||
+ (d->SlaveAddr & 1) || xf86I2CFindDev(b, d->SlaveAddr) != NULL)
+ return FALSE;
+
+ if (d->BitTimeout <= 0)
+ d->BitTimeout = b->BitTimeout;
+ if (d->ByteTimeout <= 0)
+ d->ByteTimeout = b->ByteTimeout;
+ if (d->AcknTimeout <= 0)
+ d->AcknTimeout = b->AcknTimeout;
+ if (d->StartTimeout <= 0)
+ d->StartTimeout = b->StartTimeout;
+
+ d->NextDev = b->FirstDev;
+ b->FirstDev = d;
+
+ xf86DrvMsg(b->scrnIndex, X_INFO,
+ "I2C device \"%s:%s\" registered at address 0x%02X.\n",
+ b->BusName, d->DevName, d->SlaveAddr);
+
+ return TRUE;
+}
+
+I2CDevPtr
+xf86I2CFindDev(I2CBusPtr b, I2CSlaveAddr addr)
+{
+ I2CDevPtr d;
+
+ if (b) {
+ for (d = b->FirstDev; d != NULL; d = d->NextDev)
+ if (d->SlaveAddr == addr)
+ return d;
+ }
+
+ return NULL;
+}
+
+static I2CBusPtr I2CBusList;
+
+/* Allocates an I2CBusRec for you and initializes with propper defaults
+ * you may modify before calling xf86I2CBusInit. Your I2CBusRec must
+ * contain at least a BusName, a scrnIndex (or -1), and a complete set
+ * of either high or low level I2C function pointers. You may pass
+ * bus-wide timeouts, otherwise inplausible values will be replaced
+ * with safe defaults.
+ */
+
+I2CBusPtr
+xf86CreateI2CBusRec(void)
+{
+ I2CBusPtr b;
+
+ b = (I2CBusPtr) calloc(1, sizeof(I2CBusRec));
+
+ if (b != NULL) {
+ b->scrnIndex = -1;
+ b->HoldTime = 5; /* 100 kHz bus */
+ b->BitTimeout = 5;
+ b->ByteTimeout = 5;
+ b->AcknTimeout = 5;
+ b->StartTimeout = 5;
+ b->RiseFallTime = RISEFALLTIME;
+ }
+
+ return b;
+}
+
+/* Unregister an I2C bus. If you got the I2CBusRec from xf86CreateI2CBusRec
+ * you should set <unalloc> to free it. If you set <devs_too>, the function
+ * xf86DestroyI2CDevRec will be called for all devices linked to the bus
+ * first, passing down the <unalloc> option.
+ */
+
+void
+xf86DestroyI2CBusRec(I2CBusPtr b, Bool unalloc, Bool devs_too)
+{
+ if (b) {
+ I2CBusPtr *p;
+
+ /* Remove this from the list of active I2C buses */
+
+ for (p = &I2CBusList; *p != NULL; p = &(*p)->NextBus)
+ if (*p == b) {
+ *p = (*p)->NextBus;
+ break;
+ }
+
+ if (b->FirstDev != NULL) {
+ if (devs_too) {
+ I2CDevPtr d;
+
+ while ((d = b->FirstDev) != NULL) {
+ b->FirstDev = d->NextDev;
+ xf86DestroyI2CDevRec(d, unalloc);
+ }
+ }
+ else {
+ if (unalloc) {
+ xf86Msg(X_ERROR,
+ "i2c bug: Attempt to remove I2C bus \"%s\", "
+ "but device list is not empty.\n", b->BusName);
+ return;
+ }
+ }
+ }
+
+ xf86DrvMsg(b->scrnIndex, X_INFO, "I2C bus \"%s\" removed.\n",
+ b->BusName);
+
+ if (unalloc)
+ free(b);
+ }
+}
+
+/* I2C masters have to register themselves using this function.
+ * It will not allocate an I2CBusRec for you, instead you may enter
+ * a pointer to a statically allocated I2CBusRec or the (modified)
+ * result of xf86CreateI2CBusRec. Returns TRUE on success.
+ *
+ * At this point there won't be any traffic on the I2C bus.
+ */
+
+Bool
+xf86I2CBusInit(I2CBusPtr b)
+{
+ /* I2C buses must be identified by a unique scrnIndex
+ * and name. If scrnIndex is unspecified (a negative value),
+ * then the name must be unique throughout the server.
+ */
+
+ if (b->BusName == NULL || xf86I2CFindBus(b->scrnIndex, b->BusName) != NULL)
+ return FALSE;
+
+ /* If the high level functions are not
+ * supplied, use the generic functions.
+ * In this case we need the low-level
+ * function.
+ */
+ if (b->I2CWriteRead == NULL) {
+ b->I2CWriteRead = I2CWriteRead;
+
+ if (b->I2CPutBits == NULL || b->I2CGetBits == NULL) {
+ if (b->I2CPutByte == NULL ||
+ b->I2CGetByte == NULL ||
+ b->I2CAddress == NULL ||
+ b->I2CStart == NULL || b->I2CStop == NULL)
+ return FALSE;
+ }
+ else {
+ b->I2CPutByte = I2CPutByte;
+ b->I2CGetByte = I2CGetByte;
+ b->I2CAddress = I2CAddress;
+ b->I2CStop = I2CStop;
+ b->I2CStart = I2CStart;
+ }
+ }
+
+ if (b->I2CUDelay == NULL)
+ b->I2CUDelay = I2CUDelay;
+
+ if (b->HoldTime < 2)
+ b->HoldTime = 5;
+ if (b->BitTimeout <= 0)
+ b->BitTimeout = b->HoldTime;
+ if (b->ByteTimeout <= 0)
+ b->ByteTimeout = b->HoldTime;
+ if (b->AcknTimeout <= 0)
+ b->AcknTimeout = b->HoldTime;
+ if (b->StartTimeout <= 0)
+ b->StartTimeout = b->HoldTime;
+
+ /* Put new bus on list. */
+
+ b->NextBus = I2CBusList;
+ I2CBusList = b;
+
+ xf86DrvMsg(b->scrnIndex, X_INFO, "I2C bus \"%s\" initialized.\n",
+ b->BusName);
+
+ return TRUE;
+}
+
+I2CBusPtr
+xf86I2CFindBus(int scrnIndex, char *name)
+{
+ I2CBusPtr p;
+
+ if (name != NULL)
+ for (p = I2CBusList; p != NULL; p = p->NextBus)
+ if (scrnIndex < 0 || p->scrnIndex == scrnIndex)
+ if (!strcmp(p->BusName, name))
+ return p;
+
+ return NULL;
+}
+
+/*
+ * Return an array of I2CBusPtr's related to a screen. The caller is
+ * responsible for freeing the array.
+ */
+int
+xf86I2CGetScreenBuses(int scrnIndex, I2CBusPtr ** pppI2CBus)
+{
+ I2CBusPtr pI2CBus;
+ int n = 0;
+
+ if (pppI2CBus)
+ *pppI2CBus = NULL;
+
+ for (pI2CBus = I2CBusList; pI2CBus; pI2CBus = pI2CBus->NextBus) {
+ if ((pI2CBus->scrnIndex >= 0) && (pI2CBus->scrnIndex != scrnIndex))
+ continue;
+
+ n++;
+
+ if (!pppI2CBus)
+ continue;
+
+ *pppI2CBus = xnfrealloc(*pppI2CBus, n * sizeof(I2CBusPtr));
+ (*pppI2CBus)[n - 1] = pI2CBus;
+ }
+
+ return n;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-11 12:27:54 +0000