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authorwdenk <wdenk>2004-10-28 00:09:35 +0000
committerwdenk <wdenk>2004-10-28 00:09:35 +0000
commit983fda8391fa0ccfd4e0fd0bfb5a5e662e07b222 (patch)
treeb39fd35e9f0bf906338bfce8f83eb7c8ff850428 /cpu/mpc8220/i2cCore.c
parente3c9b9f9287a17c2a20d9b1b77747bd209e8408b (diff)
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Patch by TsiChung Liew, 23 Sep 2004:
- add support for MPC8220 CPU - Add support for Alaska and Yukon boards
Diffstat (limited to 'cpu/mpc8220/i2cCore.c')
-rw-r--r--cpu/mpc8220/i2cCore.c627
1 files changed, 627 insertions, 0 deletions
diff --git a/cpu/mpc8220/i2cCore.c b/cpu/mpc8220/i2cCore.c
new file mode 100644
index 0000000..accf43c
--- /dev/null
+++ b/cpu/mpc8220/i2cCore.c
@@ -0,0 +1,627 @@
+/* I2cCore.c - MPC8220 PPC I2C Library */
+
+/* Copyright 2004 Freescale Semiconductor, Inc. */
+
+/*
+modification history
+--------------------
+01c,29jun04,tcl 1.3 removed CR. Added two bytes offset support.
+01b,19jan04,tcl 1.2 removed i2cMsDelay and sysDecGet. renamed i2cMsDelay
+ back to sysMsDelay
+01a,19jan04,tcl 1.1 created and seperated from i2c.c
+*/
+
+/*
+DESCRIPTION
+This file contain I2C low level handling library functions
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <vxWorks.h>
+#include <sysLib.h>
+#include <iosLib.h>
+#include <logLib.h>
+#include <tickLib.h>
+
+/* BSP Includes */
+#include "config.h"
+#include "mpc8220.h"
+#include "i2cCore.h"
+
+#ifdef DEBUG_I2CCORE
+int I2CCDbg = 0;
+#endif
+
+#define ABS(x) ((x < 0)? -x : x)
+
+char *I2CERR[16] = {
+ "Transfer in Progress\n", /* 0 */
+ "Transfer complete\n",
+ "Not Addressed\n", /* 2 */
+ "Addressed as a slave\n",
+ "Bus is Idle\n", /* 4 */
+ "Bus is busy\n",
+ "Arbitration Lost\n", /* 6 */
+ "Arbitration on Track\n",
+ "Slave receive, master writing to slave\n", /* 8 */
+ "Slave transmit, master reading from slave\n",
+ "Interrupt is pending\n", /* 10 */
+ "Interrupt complete\n",
+ "Acknowledge received\n", /* 12 */
+ "No acknowledge received\n",
+ "Unknown status\n", /* 14 */
+ "\n"
+};
+
+/******************************************************************************
+ *
+ * chk_status - Check I2C status bit
+ *
+ * RETURNS: OK, or ERROR if the bit encounter
+ *
+ */
+
+STATUS chk_status (PSI2C pi2c, UINT8 sta_bit, UINT8 truefalse)
+{
+ int i, status = 0;
+
+ for (i = 0; i < I2C_POLL_COUNT; i++) {
+ if ((pi2c->sr & sta_bit) == (truefalse ? sta_bit : 0))
+ return (OK);
+ }
+
+ I2CCDBG (L2, ("--- sr %x stabit %x truefalse %d\n",
+ pi2c->sr, sta_bit, truefalse, 0, 0, 0));
+
+ if (i == I2C_POLL_COUNT) {
+ switch (sta_bit) {
+ case I2C_STA_CF:
+ status = 0;
+ break;
+ case I2C_STA_AAS:
+ status = 2;
+ break;
+ case I2C_STA_BB:
+ status = 4;
+ break;
+ case I2C_STA_AL:
+ status = 6;
+ break;
+ case I2C_STA_SRW:
+ status = 8;
+ break;
+ case I2C_STA_IF:
+ status = 10;
+ break;
+ case I2C_STA_RXAK:
+ status = 12;
+ break;
+ default:
+ status = 14;
+ break;
+ }
+
+ if (!truefalse)
+ status++;
+
+ I2CCDBG (NO, ("--- status %d\n", status, 0, 0, 0, 0, 0));
+ I2CCDBG (NO, (I2CERR[status], 0, 0, 0, 0, 0, 0));
+ }
+
+ return (ERROR);
+}
+
+/******************************************************************************
+ *
+ * I2C Enable - Enable the I2C Controller
+ *
+ */
+STATUS i2c_enable (SI2C * pi2c, PI2CSET pi2cSet)
+{
+ int fdr = pi2cSet->bit_rate;
+ UINT8 adr = pi2cSet->i2c_adr;
+
+ I2CCDBG (L2, ("i2c_enable fdr %d adr %x\n", fdr, adr, 0, 0, 0, 0));
+
+ i2c_clear (pi2c); /* Clear FDR, ADR, SR and CR reg */
+
+ SetI2cFDR (pi2c, fdr); /* Frequency */
+ pi2c->adr = adr;
+
+ pi2c->cr = I2C_CTL_EN; /* Set Enable */
+
+ /*
+ The I2C bus should be in Idle state. If the bus is busy,
+ clear the STA bit in control register
+ */
+ if (chk_status (pi2c, I2C_STA_BB, 0) != OK) {
+ if ((pi2c->cr & I2C_CTL_STA) == I2C_CTL_STA)
+ pi2c->cr &= ~I2C_CTL_STA;
+
+ /* Check again if it is still busy, return error if found */
+ if (chk_status (pi2c, I2C_STA_BB, 1) == OK)
+ return ERROR;
+ }
+
+ return (OK);
+}
+
+/******************************************************************************
+ *
+ * I2C Disable - Disable the I2C Controller
+ *
+ */
+STATUS i2c_disable (PSI2C pi2c)
+{
+ i2c_clear (pi2c);
+
+ pi2c->cr &= I2C_CTL_EN; /* Disable I2c */
+
+ if ((pi2c->cr & I2C_CTL_STA) == I2C_CTL_STA)
+ pi2c->cr &= ~I2C_CTL_STA;
+
+ if (chk_status (pi2c, I2C_STA_BB, 0) != OK)
+ return ERROR;
+
+ return (OK);
+}
+
+/******************************************************************************
+ *
+ * I2C Clear - Clear the I2C Controller
+ *
+ */
+STATUS i2c_clear (PSI2C pi2c)
+{
+ pi2c->adr = 0;
+ pi2c->fdr = 0;
+ pi2c->cr = 0;
+ pi2c->sr = 0;
+
+ return (OK);
+}
+
+
+STATUS i2c_start (PSI2C pi2c, PI2CSET pi2cSet)
+{
+#ifdef TWOBYTES
+ UINT16 ByteOffset = pi2cSet->str_adr;
+#else
+ UINT8 ByteOffset = pi2cSet->str_adr;
+#endif
+#if 1
+ UINT8 tmp = 0;
+#endif
+ UINT8 Addr = pi2cSet->slv_adr;
+
+ pi2c->cr |= I2C_CTL_STA; /* Generate start signal */
+
+ if (chk_status (pi2c, I2C_STA_BB, 1) != OK)
+ return ERROR;
+
+ /* Write slave address */
+ if (i2c_writebyte (pi2c, &Addr) != OK) {
+ i2c_stop (pi2c); /* Disable I2c */
+ return ERROR;
+ }
+#ifdef TWOBYTES
+# if 0
+ /* Issue the offset to start */
+ if (i2c_write2byte (pi2c, &ByteOffset) != OK) {
+ i2c_stop (pi2c); /* Disable I2c */
+ return ERROR;
+ }
+#endif
+ tmp = (ByteOffset >> 8) & 0xff;
+ if (i2c_writebyte (pi2c, &tmp) != OK) {
+ i2c_stop (pi2c); /* Disable I2c */
+ return ERROR;
+ }
+ tmp = ByteOffset & 0xff;
+ if (i2c_writebyte (pi2c, &tmp) != OK) {
+ i2c_stop (pi2c); /* Disable I2c */
+ return ERROR;
+ }
+#else
+ if (i2c_writebyte (pi2c, &ByteOffset) != OK) {
+ i2c_stop (pi2c); /* Disable I2c */
+ return ERROR;
+ }
+#endif
+
+ return (OK);
+}
+
+STATUS i2c_stop (PSI2C pi2c)
+{
+ pi2c->cr &= ~I2C_CTL_STA; /* Generate stop signal */
+ if (chk_status (pi2c, I2C_STA_BB, 0) != OK)
+ return ERROR;
+
+ return (OK);
+}
+
+/******************************************************************************
+ *
+ * Read Len bytes to the location pointed to by *Data from the device
+ * with address Addr.
+ */
+int i2c_readblock (SI2C * pi2c, PI2CSET pi2cSet, UINT8 * Data)
+{
+ int i = 0;
+ UINT8 Tmp;
+
+/* UINT8 ByteOffset = pi2cSet->str_adr; not used? */
+ UINT8 Addr = pi2cSet->slv_adr;
+ int Length = pi2cSet->xfer_size;
+
+ I2CCDBG (L1, ("i2c_readblock addr %x data 0x%08x len %d offset %d\n",
+ Addr, (int) Data, Length, ByteOffset, 0, 0));
+
+ if (pi2c->sr & I2C_STA_AL) { /* Check if Arbitration lost */
+ I2CCDBG (FN, ("Arbitration lost\n", 0, 0, 0, 0, 0, 0));
+ pi2c->sr &= ~I2C_STA_AL; /* Clear Arbitration status bit */
+ return ERROR;
+ }
+
+ pi2c->cr |= I2C_CTL_TX; /* Enable the I2c for TX, Ack */
+
+ if (i2c_start (pi2c, pi2cSet) == ERROR)
+ return ERROR;
+
+ pi2c->cr |= I2C_CTL_RSTA; /* Repeat Start */
+
+ Tmp = Addr | 1;
+
+ if (i2c_writebyte (pi2c, &Tmp) != OK) {
+ i2c_stop (pi2c); /* Disable I2c */
+ return ERROR;
+ }
+
+ if (((pi2c->sr & 0x07) == 0x07) || (pi2c->sr & 0x01))
+ return ERROR;
+
+ pi2c->cr &= ~I2C_CTL_TX; /* Set receive mode */
+
+ if (((pi2c->sr & 0x07) == 0x07) || (pi2c->sr & 0x01))
+ return ERROR;
+
+ /* Dummy Read */
+ if (i2c_readbyte (pi2c, &Tmp, &i) != OK) {
+ i2c_stop (pi2c); /* Disable I2c */
+ return ERROR;
+ }
+
+ i = 0;
+ while (Length) {
+ if (Length == 2)
+ pi2c->cr |= I2C_CTL_TXAK;
+
+ if (Length == 1)
+ pi2c->cr &= ~I2C_CTL_STA;
+
+ if (i2c_readbyte (pi2c, Data, &Length) != OK) {
+ return i2c_stop (pi2c);
+ }
+ i++;
+ Length--;
+ Data++;
+ }
+
+ if (i2c_stop (pi2c) == ERROR)
+ return ERROR;
+
+ return i;
+}
+
+STATUS i2c_writeblock (SI2C * pi2c, PI2CSET pi2cSet, UINT8 * Data)
+{
+ int Length = pi2cSet->xfer_size;
+
+#ifdef TWOBYTES
+ UINT16 ByteOffset = pi2cSet->str_adr;
+#else
+ UINT8 ByteOffset = pi2cSet->str_adr;
+#endif
+ int j, k;
+
+ I2CCDBG (L2, ("i2c_writeblock\n", 0, 0, 0, 0, 0, 0));
+
+ if (pi2c->sr & I2C_STA_AL) {
+ /* Check if arbitration lost */
+ I2CCDBG (L2, ("Arbitration lost\n", 0, 0, 0, 0, 0, 0));
+ pi2c->sr &= ~I2C_STA_AL; /* Clear the condition */
+ return ERROR;
+ }
+
+ pi2c->cr |= I2C_CTL_TX; /* Enable the I2c for TX, Ack */
+
+ /* Do the not even offset first */
+ if ((ByteOffset % 8) != 0) {
+ int remain;
+
+ if (Length > 8) {
+ remain = 8 - (ByteOffset % 8);
+ Length -= remain;
+
+ pi2cSet->str_adr = ByteOffset;
+
+ if (i2c_start (pi2c, pi2cSet) == ERROR)
+ return ERROR;
+
+ for (j = ByteOffset; j < remain; j++) {
+ if (i2c_writebyte (pi2c, Data++) != OK)
+ return ERROR;
+ }
+
+ if (i2c_stop (pi2c) == ERROR)
+ return ERROR;
+
+ sysMsDelay (32);
+
+ /* Update the new ByteOffset */
+ ByteOffset += remain;
+ }
+ }
+
+ for (j = ByteOffset, k = 0; j < (Length + ByteOffset); j++) {
+ if ((j % 8) == 0) {
+ pi2cSet->str_adr = j;
+ if (i2c_start (pi2c, pi2cSet) == ERROR)
+ return ERROR;
+ }
+
+ k++;
+
+ if (i2c_writebyte (pi2c, Data++) != OK)
+ return ERROR;
+
+ if ((j == (Length - 1)) || ((k % 8) == 0)) {
+ if (i2c_stop (pi2c) == ERROR)
+ return ERROR;
+
+ sysMsDelay (50);
+ }
+
+ }
+
+ return k;
+}
+
+STATUS i2c_readbyte (SI2C * pi2c, UINT8 * readb, int *index)
+{
+ pi2c->sr &= ~I2C_STA_IF; /* Clear Interrupt Bit */
+ *readb = pi2c->dr; /* Read a byte */
+
+ /*
+ Set I2C_CTRL_TXAK will cause Transfer pending and
+ set I2C_CTRL_STA will cause Interrupt pending
+ */
+ if (*index != 2) {
+ if (chk_status (pi2c, I2C_STA_CF, 1) != OK) /* Transfer not complete? */
+ return ERROR;
+ }
+
+ if (*index != 1) {
+ if (chk_status (pi2c, I2C_STA_IF, 1) != OK)
+ return ERROR;
+ }
+
+ return (OK);
+}
+
+
+STATUS i2c_writebyte (SI2C * pi2c, UINT8 * writeb)
+{
+ pi2c->sr &= ~I2C_STA_IF; /* Clear Interrupt */
+ pi2c->dr = *writeb; /* Write a byte */
+
+ if (chk_status (pi2c, I2C_STA_CF, 1) != OK) /* Transfer not complete? */
+ return ERROR;
+
+ if (chk_status (pi2c, I2C_STA_IF, 1) != OK)
+ return ERROR;
+
+ return OK;
+}
+
+STATUS i2c_write2byte (SI2C * pi2c, UINT16 * writeb)
+{
+ UINT8 data;
+
+ data = (UINT8) ((*writeb >> 8) & 0xff);
+ if (i2c_writebyte (pi2c, &data) != OK)
+ return ERROR;
+ data = (UINT8) (*writeb & 0xff);
+ if (i2c_writebyte (pi2c, &data) != OK)
+ return ERROR;
+ return OK;
+}
+
+/* FDR table base on 33Mhz - more detail please refer to Odini2c_dividers.xls
+FDR FDR scl sda scl2tap2
+510 432 tap tap tap tap scl_per sda_hold I2C Freq 0 1 2 3 4 5
+000 000 9 3 4 1 28 Clocks 9 Clocks 1190 KHz 0 0 0 0 0 0
+000 001 9 3 4 2 44 Clocks 11 Clocks 758 KHz 0 0 1 0 0 0
+000 010 9 3 6 4 80 Clocks 17 Clocks 417 KHz 0 0 0 1 0 0
+000 011 9 3 6 8 144 Clocks 25 Clocks 231 KHz 0 0 1 1 0 0
+000 100 9 3 14 16 288 Clocks 49 Clocks 116 KHz 0 0 0 0 1 0
+000 101 9 3 30 32 576 Clocks 97 Clocks 58 KHz 0 0 1 0 1 0
+000 110 9 3 62 64 1152 Clocks 193 Clocks 29 KHz 0 0 0 1 1 0
+000 111 9 3 126 128 2304 Clocks 385 Clocks 14 KHz 0 0 1 1 1 0
+001 000 10 3 4 1 30 Clocks 9 Clocks 1111 KHz1 0 0 0 0 0
+001 001 10 3 4 2 48 Clocks 11 Clocks 694 KHz 1 0 1 0 0 0
+001 010 10 3 6 4 88 Clocks 17 Clocks 379 KHz 1 0 0 1 0 0
+001 011 10 3 6 8 160 Clocks 25 Clocks 208 KHz 1 0 1 1 0 0
+001 100 10 3 14 16 320 Clocks 49 Clocks 104 KHz 1 0 0 0 1 0
+001 101 10 3 30 32 640 Clocks 97 Clocks 52 KHz 1 0 1 0 1 0
+001 110 10 3 62 64 1280 Clocks 193 Clocks 26 KHz 1 0 0 1 1 0
+001 111 10 3 126 128 2560 Clocks 385 Clocks 13 KHz 1 0 1 1 1 0
+010 000 12 4 4 1 34 Clocks 10 Clocks 980 KHz 0 1 0 0 0 0
+010 001 12 4 4 2 56 Clocks 13 Clocks 595 KHz 0 1 1 0 0 0
+010 010 12 4 6 4 104 Clocks 21 Clocks 321 KHz 0 1 0 1 0 0
+010 011 12 4 6 8 192 Clocks 33 Clocks 174 KHz 0 1 1 1 0 0
+010 100 12 4 14 16 384 Clocks 65 Clocks 87 KHz 0 1 0 0 1 0
+010 101 12 4 30 32 768 Clocks 129 Clocks 43 KHz 0 1 1 0 1 0
+010 110 12 4 62 64 1536 Clocks 257 Clocks 22 KHz 0 1 0 1 1 0
+010 111 12 4 126 128 3072 Clocks 513 Clocks 11 KHz 0 1 1 1 1 0
+011 000 15 4 4 1 40 Clocks 10 Clocks 833 KHz 1 1 0 0 0 0
+011 001 15 4 4 2 68 Clocks 13 Clocks 490 KHz 1 1 1 0 0 0
+011 010 15 4 6 4 128 Clocks 21 Clocks 260 KHz 1 1 0 1 0 0
+011 011 15 4 6 8 240 Clocks 33 Clocks 139 KHz 1 1 1 1 0 0
+011 100 15 4 14 16 480 Clocks 65 Clocks 69 KHz 1 1 0 0 1 0
+011 101 15 4 30 32 960 Clocks 129 Clocks 35 KHz 1 1 1 0 1 0
+011 110 15 4 62 64 1920 Clocks 257 Clocks 17 KHz 1 1 0 1 1 0
+011 111 15 4 126 128 3840 Clocks 513 Clocks 9 KHz 1 1 1 1 1 0
+100 000 5 1 4 1 20 Clocks 7 Clocks 1667 KHz 0 0 0 0 0 1
+100 001 5 1 4 2 28 Clocks 7 Clocks 1190 KHz 0 0 1 0 0 1
+100 010 5 1 6 4 48 Clocks 9 Clocks 694 KHz 0 0 0 1 0 1
+100 011 5 1 6 8 80 Clocks 9 Clocks 417 KHz 0 0 1 1 0 1
+100 100 5 1 14 16 160 Clocks 17 Clocks 208 KHz 0 0 0 0 1 1
+100 101 5 1 30 32 320 Clocks 33 Clocks 104 KHz 0 0 1 0 1 1
+100 110 5 1 62 64 640 Clocks 65 Clocks 52 KHz 0 0 0 1 1 1
+100 111 5 1 126 128 1280 Clocks 129 Clocks 26 KHz 0 0 1 1 1 1
+101 000 6 1 4 1 22 Clocks 7 Clocks 1515 KHz 1 0 0 0 0 1
+101 001 6 1 4 2 32 Clocks 7 Clocks 1042 KHz 1 0 1 0 0 1
+101 010 6 1 6 4 56 Clocks 9 Clocks 595 KHz 1 0 0 1 0 1
+101 011 6 1 6 8 96 Clocks 9 Clocks 347 KHz 1 0 1 1 0 1
+101 100 6 1 14 16 192 Clocks 17 Clocks 174 KHz 1 0 0 0 1 1
+101 101 6 1 30 32 384 Clocks 33 Clocks 87 KHz 1 0 1 0 1 1
+101 110 6 1 62 64 768 Clocks 65 Clocks 43 KHz 1 0 0 1 1 1
+101 111 6 1 126 128 1536 Clocks 129 Clocks 22 KHz 1 0 1 1 1 1
+110 000 7 2 4 1 24 Clocks 8 Clocks 1389 KHz 0 1 0 0 0 1
+110 001 7 2 4 2 36 Clocks 9 Clocks 926 KHz 0 1 1 0 0 1
+110 010 7 2 6 4 64 Clocks 13 Clocks 521 KHz 0 1 0 1 0 1
+110 011 7 2 6 8 112 Clocks 17 Clocks 298 KHz 0 1 1 1 0 1
+110 100 7 2 14 16 224 Clocks 33 Clocks 149 KHz 0 1 0 0 1 1
+110 101 7 2 30 32 448 Clocks 65 Clocks 74 KHz 0 1 1 0 1 1
+110 110 7 2 62 64 896 Clocks 129 Clocks 37 KHz 0 1 0 1 1 1
+110 111 7 2 126 128 1792 Clocks 257 Clocks 19 KHz 0 1 1 1 1 1
+111 000 8 2 4 1 26 Clocks 8 Clocks 1282 KHz 1 1 0 0 0 1
+111 001 8 2 4 2 40 Clocks 9 Clocks 833 KHz 1 1 1 0 0 1
+111 010 8 2 6 4 72 Clocks 13 Clocks 463 KHz 1 1 0 1 0 1
+111 011 8 2 6 8 128 Clocks 17 Clocks 260 KHz 1 1 1 1 0 1
+111 100 8 2 14 16 256 Clocks 33 Clocks 130 KHz 1 1 0 0 1 1
+111 101 8 2 30 32 512 Clocks 65 Clocks 65 KHz 1 1 1 0 1 1
+111 110 8 2 62 64 1024 Clocks 129 Clocks 33 KHz 1 1 0 1 1 1
+111 111 8 2 126 128 2048 Clocks 257 Clocks 16 KHz 1 1 1 1 1 1
+*/
+STATUS SetI2cFDR (PSI2C pi2cRegs, int bitrate)
+{
+/* Constants */
+ const UINT8 div_hold[8][3] = { {9, 3}, {10, 3},
+ {12, 4}, {15, 4},
+ {5, 1}, {6, 1},
+ {7, 2}, {8, 2}
+ };
+
+ const UINT8 scl_tap[8][2] = { {4, 1}, {4, 2},
+ {6, 4}, {6, 8},
+ {14, 16}, {30, 32},
+ {62, 64}, {126, 128}
+ };
+
+ UINT8 mfdr_bits;
+
+ int i = 0;
+ int j = 0;
+
+ int Diff, min;
+ int WhichFreq, iRec, jRec;
+ int SCL_Period;
+ int SCL_Hold;
+ int I2C_Freq;
+
+ I2CCDBG (L2, ("Entering getBitRate: bitrate %d pi2cRegs 0x%08x\n",
+ bitrate, (int) pi2cRegs, 0, 0, 0, 0));
+
+ if (bitrate < 0) {
+ I2CCDBG (NO, ("Invalid bitrate\n", 0, 0, 0, 0, 0, 0));
+ return ERROR;
+ }
+
+ /* Initialize */
+ mfdr_bits = 0;
+ min = 0x7fffffff;
+ WhichFreq = iRec = jRec = 0;
+
+ for (i = 0; i < 8; i++) {
+ for (j = 0; j < 8; j++) {
+ /* SCL Period = 2 * (scl2tap + [(SCL_Tap - 1) * tap2tap] + 2)
+ * SCL Hold = scl2tap + ((SDA_Tap - 1) * tap2tap) + 3
+ * Bit Rate (I2C Freq) = System Freq / SCL Period
+ */
+ SCL_Period =
+ 2 * (scl_tap[i][0] +
+ ((div_hold[j][0] - 1) * scl_tap[i][1]) +
+ 2);
+
+ /* Now get the I2C Freq */
+ I2C_Freq = DEV_CLOCK_FREQ / SCL_Period;
+
+ /* Take equal or slower */
+ if (I2C_Freq > bitrate)
+ continue;
+
+ /* Take the differences */
+ Diff = I2C_Freq - bitrate;
+
+ Diff = ABS (Diff);
+
+ /* Find the closer value */
+ if (Diff < min) {
+ min = Diff;
+ WhichFreq = I2C_Freq;
+ iRec = i;
+ jRec = j;
+ }
+
+ I2CCDBG (L2,
+ ("--- (%d,%d) I2C_Freq %d minDiff %d min %d\n",
+ i, j, I2C_Freq, Diff, min, 0));
+ }
+ }
+
+ SCL_Period =
+ 2 * (scl_tap[iRec][0] +
+ ((div_hold[jRec][0] - 1) * scl_tap[iRec][1]) + 2);
+
+ I2CCDBG (L2, ("\nmin %d WhichFreq %d iRec %d jRec %d\n",
+ min, WhichFreq, iRec, jRec, 0, 0));
+ I2CCDBG (L2, ("--- scl2tap %d SCL_Tap %d tap2tap %d\n",
+ scl_tap[iRec][0], div_hold[jRec][0], scl_tap[iRec][1],
+ 0, 0, 0));
+
+ /* This may no require */
+ SCL_Hold =
+ scl_tap[iRec][0] +
+ ((div_hold[jRec][1] - 1) * scl_tap[iRec][1]) + 3;
+ I2CCDBG (L2,
+ ("--- SCL_Period %d SCL_Hold %d\n", SCL_Period, SCL_Hold, 0,
+ 0, 0, 0));
+
+ I2CCDBG (L2, ("--- mfdr_bits %x\n", mfdr_bits, 0, 0, 0, 0, 0));
+
+ /* FDR 4,3,2 */
+ if ((iRec & 1) == 1)
+ mfdr_bits |= 0x04; /* FDR 2 */
+ if ((iRec & 2) == 2)
+ mfdr_bits |= 0x08; /* FDR 3 */
+ if ((iRec & 4) == 4)
+ mfdr_bits |= 0x10; /* FDR 4 */
+ /* FDR 5,1,0 */
+ if ((jRec & 1) == 1)
+ mfdr_bits |= 0x01; /* FDR 0 */
+ if ((jRec & 2) == 2)
+ mfdr_bits |= 0x02; /* FDR 1 */
+ if ((jRec & 4) == 4)
+ mfdr_bits |= 0x20; /* FDR 5 */
+
+ I2CCDBG (L2, ("--- mfdr_bits %x\n", mfdr_bits, 0, 0, 0, 0, 0));
+
+ pi2cRegs->fdr = mfdr_bits;
+
+ return OK;
+}