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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/i2c/algos/i2c-algo-ite.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/i2c/algos/i2c-algo-ite.c')
-rw-r--r--drivers/i2c/algos/i2c-algo-ite.c812
1 files changed, 812 insertions, 0 deletions
diff --git a/drivers/i2c/algos/i2c-algo-ite.c b/drivers/i2c/algos/i2c-algo-ite.c
new file mode 100644
index 000000000000..68e9e6832ca0
--- /dev/null
+++ b/drivers/i2c/algos/i2c-algo-ite.c
@@ -0,0 +1,812 @@
+/*
+ -------------------------------------------------------------------------
+ i2c-algo-ite.c i2c driver algorithms for ITE adapters
+
+ Hai-Pao Fan, MontaVista Software, Inc.
+ hpfan@mvista.com or source@mvista.com
+
+ Copyright 2000 MontaVista Software Inc.
+
+ ---------------------------------------------------------------------------
+ This file was highly leveraged from i2c-algo-pcf.c, which was created
+ by Simon G. Vogl and Hans Berglund:
+
+
+ Copyright (C) 1995-1997 Simon G. Vogl
+ 1998-2000 Hans Berglund
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+/* ------------------------------------------------------------------------- */
+
+/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and
+ Frodo Looijaard <frodol@dds.nl> ,and also from Martin Bailey
+ <mbailey@littlefeet-inc.com> */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <asm/uaccess.h>
+#include <linux/ioport.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+
+#include <linux/i2c.h>
+#include <linux/i2c-algo-ite.h>
+#include "i2c-algo-ite.h"
+
+#define PM_DSR IT8172_PCI_IO_BASE + IT_PM_DSR
+#define PM_IBSR IT8172_PCI_IO_BASE + IT_PM_DSR + 0x04
+#define GPIO_CCR IT8172_PCI_IO_BASE + IT_GPCCR
+
+#define DEB2(x) if (i2c_debug>=2) x
+#define DEB3(x) if (i2c_debug>=3) x /* print several statistical values*/
+#define DEF_TIMEOUT 16
+
+
+/* module parameters:
+ */
+static int i2c_debug;
+static int iic_test; /* see if the line-setting functions work */
+
+/* --- setting states on the bus with the right timing: --------------- */
+
+#define get_clock(adap) adap->getclock(adap->data)
+#define iic_outw(adap, reg, val) adap->setiic(adap->data, reg, val)
+#define iic_inw(adap, reg) adap->getiic(adap->data, reg)
+
+
+/* --- other auxiliary functions -------------------------------------- */
+
+static void iic_start(struct i2c_algo_iic_data *adap)
+{
+ iic_outw(adap,ITE_I2CHCR,ITE_CMD);
+}
+
+static void iic_stop(struct i2c_algo_iic_data *adap)
+{
+ iic_outw(adap,ITE_I2CHCR,0);
+ iic_outw(adap,ITE_I2CHSR,ITE_I2CHSR_TDI);
+}
+
+static void iic_reset(struct i2c_algo_iic_data *adap)
+{
+ iic_outw(adap, PM_IBSR, iic_inw(adap, PM_IBSR) | 0x80);
+}
+
+
+static int wait_for_bb(struct i2c_algo_iic_data *adap)
+{
+ int timeout = DEF_TIMEOUT;
+ short status;
+
+ status = iic_inw(adap, ITE_I2CHSR);
+#ifndef STUB_I2C
+ while (timeout-- && (status & ITE_I2CHSR_HB)) {
+ udelay(1000); /* How much is this? */
+ status = iic_inw(adap, ITE_I2CHSR);
+ }
+#endif
+ if (timeout<=0) {
+ printk(KERN_ERR "Timeout, host is busy\n");
+ iic_reset(adap);
+ }
+ return(timeout<=0);
+}
+
+/* After we issue a transaction on the IIC bus, this function
+ * is called. It puts this process to sleep until we get an interrupt from
+ * from the controller telling us that the transaction we requested in complete.
+ */
+static int wait_for_pin(struct i2c_algo_iic_data *adap, short *status) {
+
+ int timeout = DEF_TIMEOUT;
+
+ timeout = wait_for_bb(adap);
+ if (timeout) {
+ DEB2(printk("Timeout waiting for host not busy\n");)
+ return -EIO;
+ }
+ timeout = DEF_TIMEOUT;
+
+ *status = iic_inw(adap, ITE_I2CHSR);
+#ifndef STUB_I2C
+ while (timeout-- && !(*status & ITE_I2CHSR_TDI)) {
+ adap->waitforpin();
+ *status = iic_inw(adap, ITE_I2CHSR);
+ }
+#endif
+ if (timeout <= 0)
+ return(-1);
+ else
+ return(0);
+}
+
+static int wait_for_fe(struct i2c_algo_iic_data *adap, short *status)
+{
+ int timeout = DEF_TIMEOUT;
+
+ *status = iic_inw(adap, ITE_I2CFSR);
+#ifndef STUB_I2C
+ while (timeout-- && (*status & ITE_I2CFSR_FE)) {
+ udelay(1000);
+ iic_inw(adap, ITE_I2CFSR);
+ }
+#endif
+ if (timeout <= 0)
+ return(-1);
+ else
+ return(0);
+}
+
+static int iic_init (struct i2c_algo_iic_data *adap)
+{
+ short i;
+
+ /* Clear bit 7 to set I2C to normal operation mode */
+ i=iic_inw(adap, PM_DSR)& 0xff7f;
+ iic_outw(adap, PM_DSR, i);
+
+ /* set IT_GPCCR port C bit 2&3 as function 2 */
+ i = iic_inw(adap, GPIO_CCR) & 0xfc0f;
+ iic_outw(adap,GPIO_CCR,i);
+
+ /* Clear slave address/sub-address */
+ iic_outw(adap,ITE_I2CSAR, 0);
+ iic_outw(adap,ITE_I2CSSAR, 0);
+
+ /* Set clock counter register */
+ iic_outw(adap,ITE_I2CCKCNT, get_clock(adap));
+
+ /* Set START/reSTART/STOP time registers */
+ iic_outw(adap,ITE_I2CSHDR, 0x0a);
+ iic_outw(adap,ITE_I2CRSUR, 0x0a);
+ iic_outw(adap,ITE_I2CPSUR, 0x0a);
+
+ /* Enable interrupts on completing the current transaction */
+ iic_outw(adap,ITE_I2CHCR, ITE_I2CHCR_IE | ITE_I2CHCR_HCE);
+
+ /* Clear transfer count */
+ iic_outw(adap,ITE_I2CFBCR, 0x0);
+
+ DEB2(printk("iic_init: Initialized IIC on ITE 0x%x\n",
+ iic_inw(adap, ITE_I2CHSR)));
+ return 0;
+}
+
+
+/*
+ * Sanity check for the adapter hardware - check the reaction of
+ * the bus lines only if it seems to be idle.
+ */
+static int test_bus(struct i2c_algo_iic_data *adap, char *name) {
+#if 0
+ int scl,sda;
+ sda=getsda(adap);
+ if (adap->getscl==NULL) {
+ printk("test_bus: Warning: Adapter can't read from clock line - skipping test.\n");
+ return 0;
+ }
+ scl=getscl(adap);
+ printk("test_bus: Adapter: %s scl: %d sda: %d -- testing...\n",
+ name,getscl(adap),getsda(adap));
+ if (!scl || !sda ) {
+ printk("test_bus: %s seems to be busy.\n",adap->name);
+ goto bailout;
+ }
+ sdalo(adap);
+ printk("test_bus:1 scl: %d sda: %d \n",getscl(adap),
+ getsda(adap));
+ if ( 0 != getsda(adap) ) {
+ printk("test_bus: %s SDA stuck high!\n",name);
+ sdahi(adap);
+ goto bailout;
+ }
+ if ( 0 == getscl(adap) ) {
+ printk("test_bus: %s SCL unexpected low while pulling SDA low!\n",
+ name);
+ goto bailout;
+ }
+ sdahi(adap);
+ printk("test_bus:2 scl: %d sda: %d \n",getscl(adap),
+ getsda(adap));
+ if ( 0 == getsda(adap) ) {
+ printk("test_bus: %s SDA stuck low!\n",name);
+ sdahi(adap);
+ goto bailout;
+ }
+ if ( 0 == getscl(adap) ) {
+ printk("test_bus: %s SCL unexpected low while SDA high!\n",
+ adap->name);
+ goto bailout;
+ }
+ scllo(adap);
+ printk("test_bus:3 scl: %d sda: %d \n",getscl(adap),
+ getsda(adap));
+ if ( 0 != getscl(adap) ) {
+
+ sclhi(adap);
+ goto bailout;
+ }
+ if ( 0 == getsda(adap) ) {
+ printk("test_bus: %s SDA unexpected low while pulling SCL low!\n",
+ name);
+ goto bailout;
+ }
+ sclhi(adap);
+ printk("test_bus:4 scl: %d sda: %d \n",getscl(adap),
+ getsda(adap));
+ if ( 0 == getscl(adap) ) {
+ printk("test_bus: %s SCL stuck low!\n",name);
+ sclhi(adap);
+ goto bailout;
+ }
+ if ( 0 == getsda(adap) ) {
+ printk("test_bus: %s SDA unexpected low while SCL high!\n",
+ name);
+ goto bailout;
+ }
+ printk("test_bus: %s passed test.\n",name);
+ return 0;
+bailout:
+ sdahi(adap);
+ sclhi(adap);
+ return -ENODEV;
+#endif
+ return (0);
+}
+
+/* ----- Utility functions
+ */
+
+
+/* Verify the device we want to talk to on the IIC bus really exists. */
+static inline int try_address(struct i2c_algo_iic_data *adap,
+ unsigned int addr, int retries)
+{
+ int i, ret = -1;
+ short status;
+
+ for (i=0;i<retries;i++) {
+ iic_outw(adap, ITE_I2CSAR, addr);
+ iic_start(adap);
+ if (wait_for_pin(adap, &status) == 0) {
+ if ((status & ITE_I2CHSR_DNE) == 0) {
+ iic_stop(adap);
+ iic_outw(adap, ITE_I2CFCR, ITE_I2CFCR_FLUSH);
+ ret=1;
+ break; /* success! */
+ }
+ }
+ iic_stop(adap);
+ udelay(adap->udelay);
+ }
+ DEB2(if (i) printk("try_address: needed %d retries for 0x%x\n",i,
+ addr));
+ return ret;
+}
+
+
+static int iic_sendbytes(struct i2c_adapter *i2c_adap,const char *buf,
+ int count)
+{
+ struct i2c_algo_iic_data *adap = i2c_adap->algo_data;
+ int wrcount=0, timeout;
+ short status;
+ int loops, remainder, i, j;
+ union {
+ char byte[2];
+ unsigned short word;
+ } tmp;
+
+ iic_outw(adap, ITE_I2CSSAR, (unsigned short)buf[wrcount++]);
+ count--;
+ if (count == 0)
+ return -EIO;
+
+ loops = count / 32; /* 32-byte FIFO */
+ remainder = count % 32;
+
+ if(loops) {
+ for(i=0; i<loops; i++) {
+
+ iic_outw(adap, ITE_I2CFBCR, 32);
+ for(j=0; j<32/2; j++) {
+ tmp.byte[1] = buf[wrcount++];
+ tmp.byte[0] = buf[wrcount++];
+ iic_outw(adap, ITE_I2CFDR, tmp.word);
+ }
+
+ /* status FIFO overrun */
+ iic_inw(adap, ITE_I2CFSR);
+ iic_inw(adap, ITE_I2CFBCR);
+
+ iic_outw(adap, ITE_I2CHCR, ITE_WRITE); /* Issue WRITE command */
+
+ /* Wait for transmission to complete */
+ timeout = wait_for_pin(adap, &status);
+ if(timeout) {
+ iic_stop(adap);
+ printk("iic_sendbytes: %s write timeout.\n", i2c_adap->name);
+ return -EREMOTEIO; /* got a better one ?? */
+ }
+ if (status & ITE_I2CHSR_DB) {
+ iic_stop(adap);
+ printk("iic_sendbytes: %s write error - no ack.\n", i2c_adap->name);
+ return -EREMOTEIO; /* got a better one ?? */
+ }
+ }
+ }
+ if(remainder) {
+ iic_outw(adap, ITE_I2CFBCR, remainder);
+ for(i=0; i<remainder/2; i++) {
+ tmp.byte[1] = buf[wrcount++];
+ tmp.byte[0] = buf[wrcount++];
+ iic_outw(adap, ITE_I2CFDR, tmp.word);
+ }
+
+ /* status FIFO overrun */
+ iic_inw(adap, ITE_I2CFSR);
+ iic_inw(adap, ITE_I2CFBCR);
+
+ iic_outw(adap, ITE_I2CHCR, ITE_WRITE); /* Issue WRITE command */
+
+ timeout = wait_for_pin(adap, &status);
+ if(timeout) {
+ iic_stop(adap);
+ printk("iic_sendbytes: %s write timeout.\n", i2c_adap->name);
+ return -EREMOTEIO; /* got a better one ?? */
+ }
+#ifndef STUB_I2C
+ if (status & ITE_I2CHSR_DB) {
+ iic_stop(adap);
+ printk("iic_sendbytes: %s write error - no ack.\n", i2c_adap->name);
+ return -EREMOTEIO; /* got a better one ?? */
+ }
+#endif
+ }
+ iic_stop(adap);
+ return wrcount;
+}
+
+
+static int iic_readbytes(struct i2c_adapter *i2c_adap, char *buf, int count,
+ int sread)
+{
+ int rdcount=0, i, timeout;
+ short status;
+ struct i2c_algo_iic_data *adap = i2c_adap->algo_data;
+ int loops, remainder, j;
+ union {
+ char byte[2];
+ unsigned short word;
+ } tmp;
+
+ loops = count / 32; /* 32-byte FIFO */
+ remainder = count % 32;
+
+ if(loops) {
+ for(i=0; i<loops; i++) {
+ iic_outw(adap, ITE_I2CFBCR, 32);
+ if (sread)
+ iic_outw(adap, ITE_I2CHCR, ITE_SREAD);
+ else
+ iic_outw(adap, ITE_I2CHCR, ITE_READ); /* Issue READ command */
+
+ timeout = wait_for_pin(adap, &status);
+ if(timeout) {
+ iic_stop(adap);
+ printk("iic_readbytes: %s read timeout.\n", i2c_adap->name);
+ return (-1);
+ }
+#ifndef STUB_I2C
+ if (status & ITE_I2CHSR_DB) {
+ iic_stop(adap);
+ printk("iic_readbytes: %s read error - no ack.\n", i2c_adap->name);
+ return (-1);
+ }
+#endif
+
+ timeout = wait_for_fe(adap, &status);
+ if(timeout) {
+ iic_stop(adap);
+ printk("iic_readbytes: %s FIFO is empty\n", i2c_adap->name);
+ return (-1);
+ }
+
+ for(j=0; j<32/2; j++) {
+ tmp.word = iic_inw(adap, ITE_I2CFDR);
+ buf[rdcount++] = tmp.byte[1];
+ buf[rdcount++] = tmp.byte[0];
+ }
+
+ /* status FIFO underrun */
+ iic_inw(adap, ITE_I2CFSR);
+
+ }
+ }
+
+
+ if(remainder) {
+ remainder=(remainder+1)/2 * 2;
+ iic_outw(adap, ITE_I2CFBCR, remainder);
+ if (sread)
+ iic_outw(adap, ITE_I2CHCR, ITE_SREAD);
+ else
+ iic_outw(adap, ITE_I2CHCR, ITE_READ); /* Issue READ command */
+
+ timeout = wait_for_pin(adap, &status);
+ if(timeout) {
+ iic_stop(adap);
+ printk("iic_readbytes: %s read timeout.\n", i2c_adap->name);
+ return (-1);
+ }
+#ifndef STUB_I2C
+ if (status & ITE_I2CHSR_DB) {
+ iic_stop(adap);
+ printk("iic_readbytes: %s read error - no ack.\n", i2c_adap->name);
+ return (-1);
+ }
+#endif
+ timeout = wait_for_fe(adap, &status);
+ if(timeout) {
+ iic_stop(adap);
+ printk("iic_readbytes: %s FIFO is empty\n", i2c_adap->name);
+ return (-1);
+ }
+
+ for(i=0; i<(remainder+1)/2; i++) {
+ tmp.word = iic_inw(adap, ITE_I2CFDR);
+ buf[rdcount++] = tmp.byte[1];
+ buf[rdcount++] = tmp.byte[0];
+ }
+
+ /* status FIFO underrun */
+ iic_inw(adap, ITE_I2CFSR);
+
+ }
+
+ iic_stop(adap);
+ return rdcount;
+}
+
+
+/* This function implements combined transactions. Combined
+ * transactions consist of combinations of reading and writing blocks of data.
+ * Each transfer (i.e. a read or a write) is separated by a repeated start
+ * condition.
+ */
+#if 0
+static int iic_combined_transaction(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
+{
+ int i;
+ struct i2c_msg *pmsg;
+ int ret;
+
+ DEB2(printk("Beginning combined transaction\n"));
+
+ for(i=0; i<(num-1); i++) {
+ pmsg = &msgs[i];
+ if(pmsg->flags & I2C_M_RD) {
+ DEB2(printk(" This one is a read\n"));
+ ret = iic_readbytes(i2c_adap, pmsg->buf, pmsg->len, IIC_COMBINED_XFER);
+ }
+ else if(!(pmsg->flags & I2C_M_RD)) {
+ DEB2(printk("This one is a write\n"));
+ ret = iic_sendbytes(i2c_adap, pmsg->buf, pmsg->len, IIC_COMBINED_XFER);
+ }
+ }
+ /* Last read or write segment needs to be terminated with a stop */
+ pmsg = &msgs[i];
+
+ if(pmsg->flags & I2C_M_RD) {
+ DEB2(printk("Doing the last read\n"));
+ ret = iic_readbytes(i2c_adap, pmsg->buf, pmsg->len, IIC_SINGLE_XFER);
+ }
+ else if(!(pmsg->flags & I2C_M_RD)) {
+ DEB2(printk("Doing the last write\n"));
+ ret = iic_sendbytes(i2c_adap, pmsg->buf, pmsg->len, IIC_SINGLE_XFER);
+ }
+
+ return ret;
+}
+#endif
+
+
+/* Whenever we initiate a transaction, the first byte clocked
+ * onto the bus after the start condition is the address (7 bit) of the
+ * device we want to talk to. This function manipulates the address specified
+ * so that it makes sense to the hardware when written to the IIC peripheral.
+ *
+ * Note: 10 bit addresses are not supported in this driver, although they are
+ * supported by the hardware. This functionality needs to be implemented.
+ */
+static inline int iic_doAddress(struct i2c_algo_iic_data *adap,
+ struct i2c_msg *msg, int retries)
+{
+ unsigned short flags = msg->flags;
+ unsigned int addr;
+ int ret;
+
+/* Ten bit addresses not supported right now */
+ if ( (flags & I2C_M_TEN) ) {
+#if 0
+ addr = 0xf0 | (( msg->addr >> 7) & 0x03);
+ DEB2(printk("addr0: %d\n",addr));
+ ret = try_address(adap, addr, retries);
+ if (ret!=1) {
+ printk("iic_doAddress: died at extended address code.\n");
+ return -EREMOTEIO;
+ }
+ iic_outw(adap,msg->addr & 0x7f);
+ if (ret != 1) {
+ printk("iic_doAddress: died at 2nd address code.\n");
+ return -EREMOTEIO;
+ }
+ if ( flags & I2C_M_RD ) {
+ i2c_repstart(adap);
+ addr |= 0x01;
+ ret = try_address(adap, addr, retries);
+ if (ret!=1) {
+ printk("iic_doAddress: died at extended address code.\n");
+ return -EREMOTEIO;
+ }
+ }
+#endif
+ } else {
+
+ addr = ( msg->addr << 1 );
+
+#if 0
+ if (flags & I2C_M_RD )
+ addr |= 1;
+ if (flags & I2C_M_REV_DIR_ADDR )
+ addr ^= 1;
+#endif
+
+ if (iic_inw(adap, ITE_I2CSAR) != addr) {
+ iic_outw(adap, ITE_I2CSAR, addr);
+ ret = try_address(adap, addr, retries);
+ if (ret!=1) {
+ printk("iic_doAddress: died at address code.\n");
+ return -EREMOTEIO;
+ }
+ }
+
+ }
+
+ return 0;
+}
+
+
+/* Description: Prepares the controller for a transaction (clearing status
+ * registers, data buffers, etc), and then calls either iic_readbytes or
+ * iic_sendbytes to do the actual transaction.
+ *
+ * still to be done: Before we issue a transaction, we should
+ * verify that the bus is not busy or in some unknown state.
+ */
+static int iic_xfer(struct i2c_adapter *i2c_adap,
+ struct i2c_msg *msgs,
+ int num)
+{
+ struct i2c_algo_iic_data *adap = i2c_adap->algo_data;
+ struct i2c_msg *pmsg;
+ int i = 0;
+ int ret, timeout;
+
+ pmsg = &msgs[i];
+
+ if(!pmsg->len) {
+ DEB2(printk("iic_xfer: read/write length is 0\n");)
+ return -EIO;
+ }
+ if(!(pmsg->flags & I2C_M_RD) && (!(pmsg->len)%2) ) {
+ DEB2(printk("iic_xfer: write buffer length is not odd\n");)
+ return -EIO;
+ }
+
+ /* Wait for any pending transfers to complete */
+ timeout = wait_for_bb(adap);
+ if (timeout) {
+ DEB2(printk("iic_xfer: Timeout waiting for host not busy\n");)
+ return -EIO;
+ }
+
+ /* Flush FIFO */
+ iic_outw(adap, ITE_I2CFCR, ITE_I2CFCR_FLUSH);
+
+ /* Load address */
+ ret = iic_doAddress(adap, pmsg, i2c_adap->retries);
+ if (ret)
+ return -EIO;
+
+#if 0
+ /* Combined transaction (read and write) */
+ if(num > 1) {
+ DEB2(printk("iic_xfer: Call combined transaction\n"));
+ ret = iic_combined_transaction(i2c_adap, msgs, num);
+ }
+#endif
+
+ DEB3(printk("iic_xfer: Msg %d, addr=0x%x, flags=0x%x, len=%d\n",
+ i, msgs[i].addr, msgs[i].flags, msgs[i].len);)
+
+ if(pmsg->flags & I2C_M_RD) /* Read */
+ ret = iic_readbytes(i2c_adap, pmsg->buf, pmsg->len, 0);
+ else { /* Write */
+ udelay(1000);
+ ret = iic_sendbytes(i2c_adap, pmsg->buf, pmsg->len);
+ }
+
+ if (ret != pmsg->len)
+ DEB3(printk("iic_xfer: error or fail on read/write %d bytes.\n",ret));
+ else
+ DEB3(printk("iic_xfer: read/write %d bytes.\n",ret));
+
+ return ret;
+}
+
+
+/* Implements device specific ioctls. Higher level ioctls can
+ * be found in i2c-core.c and are typical of any i2c controller (specifying
+ * slave address, timeouts, etc). These ioctls take advantage of any hardware
+ * features built into the controller for which this algorithm-adapter set
+ * was written. These ioctls allow you to take control of the data and clock
+ * lines and set the either high or low,
+ * similar to a GPIO pin.
+ */
+static int algo_control(struct i2c_adapter *adapter,
+ unsigned int cmd, unsigned long arg)
+{
+
+ struct i2c_algo_iic_data *adap = adapter->algo_data;
+ struct i2c_iic_msg s_msg;
+ char *buf;
+ int ret;
+
+ if (cmd == I2C_SREAD) {
+ if(copy_from_user(&s_msg, (struct i2c_iic_msg *)arg,
+ sizeof(struct i2c_iic_msg)))
+ return -EFAULT;
+ buf = kmalloc(s_msg.len, GFP_KERNEL);
+ if (buf== NULL)
+ return -ENOMEM;
+
+ /* Flush FIFO */
+ iic_outw(adap, ITE_I2CFCR, ITE_I2CFCR_FLUSH);
+
+ /* Load address */
+ iic_outw(adap, ITE_I2CSAR,s_msg.addr<<1);
+ iic_outw(adap, ITE_I2CSSAR,s_msg.waddr & 0xff);
+
+ ret = iic_readbytes(adapter, buf, s_msg.len, 1);
+ if (ret>=0) {
+ if(copy_to_user( s_msg.buf, buf, s_msg.len) )
+ ret = -EFAULT;
+ }
+ kfree(buf);
+ }
+ return 0;
+}
+
+
+static u32 iic_func(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR |
+ I2C_FUNC_PROTOCOL_MANGLING;
+}
+
+/* -----exported algorithm data: ------------------------------------- */
+
+static struct i2c_algorithm iic_algo = {
+ .name = "ITE IIC algorithm",
+ .id = I2C_ALGO_IIC,
+ .master_xfer = iic_xfer,
+ .algo_control = algo_control, /* ioctl */
+ .functionality = iic_func,
+};
+
+
+/*
+ * registering functions to load algorithms at runtime
+ */
+int i2c_iic_add_bus(struct i2c_adapter *adap)
+{
+ struct i2c_algo_iic_data *iic_adap = adap->algo_data;
+
+ if (iic_test) {
+ int ret = test_bus(iic_adap, adap->name);
+ if (ret<0)
+ return -ENODEV;
+ }
+
+ DEB2(printk("i2c-algo-ite: hw routines for %s registered.\n",
+ adap->name));
+
+ /* register new adapter to i2c module... */
+
+ adap->id |= iic_algo.id;
+ adap->algo = &iic_algo;
+
+ adap->timeout = 100; /* default values, should */
+ adap->retries = 3; /* be replaced by defines */
+ adap->flags = 0;
+
+ i2c_add_adapter(adap);
+ iic_init(iic_adap);
+
+ return 0;
+}
+
+
+int i2c_iic_del_bus(struct i2c_adapter *adap)
+{
+ int res;
+ if ((res = i2c_del_adapter(adap)) < 0)
+ return res;
+ DEB2(printk("i2c-algo-ite: adapter unregistered: %s\n",adap->name));
+
+ return 0;
+}
+
+
+int __init i2c_algo_iic_init (void)
+{
+ printk(KERN_INFO "ITE iic (i2c) algorithm module\n");
+ return 0;
+}
+
+
+void i2c_algo_iic_exit(void)
+{
+ return;
+}
+
+
+EXPORT_SYMBOL(i2c_iic_add_bus);
+EXPORT_SYMBOL(i2c_iic_del_bus);
+
+/* The MODULE_* macros resolve to nothing if MODULES is not defined
+ * when this file is compiled.
+ */
+MODULE_AUTHOR("MontaVista Software <www.mvista.com>");
+MODULE_DESCRIPTION("ITE iic algorithm");
+MODULE_LICENSE("GPL");
+
+module_param(iic_test, bool, 0);
+module_param(i2c_debug, int, S_IRUGO | S_IWUSR);
+
+MODULE_PARM_DESC(iic_test, "Test if the I2C bus is available");
+MODULE_PARM_DESC(i2c_debug,
+ "debug level - 0 off; 1 normal; 2,3 more verbose; 9 iic-protocol");
+
+
+/* This function resolves to init_module (the function invoked when a module
+ * is loaded via insmod) when this file is compiled with MODULES defined.
+ * Otherwise (i.e. if you want this driver statically linked to the kernel),
+ * a pointer to this function is stored in a table and called
+ * during the initialization of the kernel (in do_basic_setup in /init/main.c)
+ *
+ * All this functionality is complements of the macros defined in linux/init.h
+ */
+module_init(i2c_algo_iic_init);
+
+
+/* If MODULES is defined when this file is compiled, then this function will
+ * resolved to cleanup_module.
+ */
+module_exit(i2c_algo_iic_exit);