-/* ------------------------------------------------------------------------- */
-/* i2c-algo-bit.c i2c driver algorithms for bit-shift adapters */
-/* ------------------------------------------------------------------------- */
-/* Copyright (C) 1995-2000 Simon G. Vogl
+/* -------------------------------------------------------------------------
+ * i2c-algo-bit.c i2c driver algorithms for bit-shift adapters
+ * -------------------------------------------------------------------------
+ * Copyright (C) 1995-2000 Simon G. Vogl
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
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. */
-/* ------------------------------------------------------------------------- */
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ * ------------------------------------------------------------------------- */
-/* With some changes from Frodo Looijaard <frodol@dds.nl>, Kyösti Mälkki
+/* With some changes from Frodo Looijaard <frodol@dds.nl>, Kyösti Mälkki
<kmalkki@cc.hut.fi> and Jean Delvare <khali@linux-fr.org> */
#include <linux/kernel.h>
/* ----- global defines ----------------------------------------------- */
-#define DEB(x) if (i2c_debug>=1) x;
-#define DEB2(x) if (i2c_debug>=2) x;
-#define DEBSTAT(x) if (i2c_debug>=3) x; /* print several statistical values*/
-#define DEBPROTO(x) if (i2c_debug>=9) { x; }
- /* debug the protocol by showing transferred bits */
+#ifdef DEBUG
+#define bit_dbg(level, dev, format, args...) \
+ do { \
+ if (i2c_debug >= level) \
+ dev_dbg(dev, format, ##args); \
+ } while (0)
+#else
+#define bit_dbg(level, dev, format, args...) \
+ do {} while (0)
+#endif /* DEBUG */
/* ----- global variables --------------------------------------------- */
-/* module parameters:
- */
-static int i2c_debug;
static int bit_test; /* see if the line-setting functions work */
+module_param(bit_test, bool, 0);
+MODULE_PARM_DESC(bit_test, "Test the lines of the bus to see if it is stuck");
+
+#ifdef DEBUG
+static int i2c_debug = 1;
+module_param(i2c_debug, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(i2c_debug,
+ "debug level - 0 off; 1 normal; 2 verbose; 3 very verbose");
+#endif
/* --- setting states on the bus with the right timing: --------------- */
-#define setsda(adap,val) adap->setsda(adap->data, val)
-#define setscl(adap,val) adap->setscl(adap->data, val)
-#define getsda(adap) adap->getsda(adap->data)
-#define getscl(adap) adap->getscl(adap->data)
+#define setsda(adap, val) adap->setsda(adap->data, val)
+#define setscl(adap, val) adap->setscl(adap->data, val)
+#define getsda(adap) adap->getsda(adap->data)
+#define getscl(adap) adap->getscl(adap->data)
static inline void sdalo(struct i2c_algo_bit_data *adap)
{
- setsda(adap,0);
- udelay(adap->udelay);
+ setsda(adap, 0);
+ udelay((adap->udelay + 1) / 2);
}
static inline void sdahi(struct i2c_algo_bit_data *adap)
{
- setsda(adap,1);
- udelay(adap->udelay);
+ setsda(adap, 1);
+ udelay((adap->udelay + 1) / 2);
}
static inline void scllo(struct i2c_algo_bit_data *adap)
{
- setscl(adap,0);
- udelay(adap->udelay);
+ setscl(adap, 0);
+ udelay(adap->udelay / 2);
}
/*
{
unsigned long start;
- setscl(adap,1);
+ setscl(adap, 1);
/* Not all adapters have scl sense line... */
if (!adap->getscl)
goto done;
- start=jiffies;
- while (! getscl(adap) ) {
- /* the hw knows how to read the clock line,
- * so we wait until it actually gets high.
- * This is safer as some chips may hold it low
- * while they are processing data internally.
- */
- if (time_after_eq(jiffies, start+adap->timeout)) {
+ start = jiffies;
+ while (!getscl(adap)) {
+ /* This hw knows how to read the clock line, so we wait
+ * until it actually gets high. This is safer as some
+ * chips may hold it low ("clock stretching") while they
+ * are processing data internally.
+ */
+ if (time_after_eq(jiffies, start + adap->timeout))
return -ETIMEDOUT;
- }
cond_resched();
}
- DEBSTAT(printk(KERN_DEBUG "needed %ld jiffies\n", jiffies-start));
+#ifdef DEBUG
+ if (jiffies != start && i2c_debug >= 3)
+ pr_debug("i2c-algo-bit: needed %ld jiffies for SCL to go "
+ "high\n", jiffies - start);
+#endif
done:
udelay(adap->udelay);
return 0;
-}
+}
/* --- other auxiliary functions -------------------------------------- */
-static void i2c_start(struct i2c_algo_bit_data *adap)
+static void i2c_start(struct i2c_algo_bit_data *adap)
{
/* assert: scl, sda are high */
- DEBPROTO(printk("S "));
- sdalo(adap);
+ setsda(adap, 0);
+ udelay(adap->udelay);
scllo(adap);
}
-static void i2c_repstart(struct i2c_algo_bit_data *adap)
+static void i2c_repstart(struct i2c_algo_bit_data *adap)
{
- /* scl, sda may not be high */
- DEBPROTO(printk(" Sr "));
- setsda(adap,1);
+ /* assert: scl is low */
+ sdahi(adap);
sclhi(adap);
-
- sdalo(adap);
+ setsda(adap, 0);
+ udelay(adap->udelay);
scllo(adap);
}
-static void i2c_stop(struct i2c_algo_bit_data *adap)
+static void i2c_stop(struct i2c_algo_bit_data *adap)
{
- DEBPROTO(printk("P\n"));
/* assert: scl is low */
sdalo(adap);
- sclhi(adap);
- sdahi(adap);
+ sclhi(adap);
+ setsda(adap, 1);
+ udelay(adap->udelay);
}
-/* send a byte without start cond., look for arbitration,
+/* send a byte without start cond., look for arbitration,
check ackn. from slave */
/* returns:
* 1 if the device acknowledged
* 0 if the device did not ack
* -ETIMEDOUT if an error occurred (while raising the scl line)
*/
-static int i2c_outb(struct i2c_adapter *i2c_adap, char c)
+static int i2c_outb(struct i2c_adapter *i2c_adap, unsigned char c)
{
int i;
int sb;
struct i2c_algo_bit_data *adap = i2c_adap->algo_data;
/* assert: scl is low */
- for ( i=7 ; i>=0 ; i-- ) {
- sb = c & ( 1 << i );
- setsda(adap,sb);
- udelay(adap->udelay);
- DEBPROTO(printk(KERN_DEBUG "%d",sb!=0));
- if (sclhi(adap)<0) { /* timed out */
- sdahi(adap); /* we don't want to block the net */
- DEB2(printk(KERN_DEBUG " i2c_outb: 0x%02x, timeout at bit #%d\n", c&0xff, i));
+ for (i = 7; i >= 0; i--) {
+ sb = (c >> i) & 1;
+ setsda(adap, sb);
+ udelay((adap->udelay + 1) / 2);
+ if (sclhi(adap) < 0) { /* timed out */
+ bit_dbg(1, &i2c_adap->dev, "i2c_outb: 0x%02x, "
+ "timeout at bit #%d\n", (int)c, i);
return -ETIMEDOUT;
- };
- /* do arbitration here:
- * if ( sb && ! getsda(adap) ) -> ouch! Get out of here.
+ }
+ /* FIXME do arbitration here:
+ * if (sb && !getsda(adap)) -> ouch! Get out of here.
+ *
+ * Report a unique code, so higher level code can retry
+ * the whole (combined) message and *NOT* issue STOP.
*/
- setscl(adap, 0 );
- udelay(adap->udelay);
+ scllo(adap);
}
sdahi(adap);
- if (sclhi(adap)<0){ /* timeout */
- DEB2(printk(KERN_DEBUG " i2c_outb: 0x%02x, timeout at ack\n", c&0xff));
- return -ETIMEDOUT;
- };
- /* read ack: SDA should be pulled down by slave */
- ack=getsda(adap); /* ack: sda is pulled low ->success. */
- DEB2(printk(KERN_DEBUG " i2c_outb: 0x%02x , getsda() = %d\n", c & 0xff, ack));
-
- DEBPROTO( printk(KERN_DEBUG "[%2.2x]",c&0xff) );
- DEBPROTO(if (0==ack){ printk(KERN_DEBUG " A ");} else printk(KERN_DEBUG " NA ") );
+ if (sclhi(adap) < 0) { /* timeout */
+ bit_dbg(1, &i2c_adap->dev, "i2c_outb: 0x%02x, "
+ "timeout at ack\n", (int)c);
+ return -ETIMEDOUT;
+ }
+
+ /* read ack: SDA should be pulled down by slave, or it may
+ * NAK (usually to report problems with the data we wrote).
+ */
+ ack = !getsda(adap); /* ack: sda is pulled low -> success */
+ bit_dbg(2, &i2c_adap->dev, "i2c_outb: 0x%02x %s\n", (int)c,
+ ack ? "A" : "NA");
+
scllo(adap);
- return 0==ack; /* return 1 if device acked */
+ return ack;
/* assert: scl is low (sda undef) */
}
-static int i2c_inb(struct i2c_adapter *i2c_adap)
+static int i2c_inb(struct i2c_adapter *i2c_adap)
{
/* read byte via i2c port, without start/stop sequence */
/* acknowledge is sent in i2c_read. */
int i;
- unsigned char indata=0;
+ unsigned char indata = 0;
struct i2c_algo_bit_data *adap = i2c_adap->algo_data;
/* assert: scl is low */
sdahi(adap);
- for (i=0;i<8;i++) {
- if (sclhi(adap)<0) { /* timeout */
- DEB2(printk(KERN_DEBUG " i2c_inb: timeout at bit #%d\n", 7-i));
+ for (i = 0; i < 8; i++) {
+ if (sclhi(adap) < 0) { /* timeout */
+ bit_dbg(1, &i2c_adap->dev, "i2c_inb: timeout at bit "
+ "#%d\n", 7 - i);
return -ETIMEDOUT;
- };
+ }
indata *= 2;
- if ( getsda(adap) )
+ if (getsda(adap))
indata |= 0x01;
- scllo(adap);
+ setscl(adap, 0);
+ udelay(i == 7 ? adap->udelay / 2 : adap->udelay);
}
/* assert: scl is low */
- DEB2(printk(KERN_DEBUG "i2c_inb: 0x%02x\n", indata & 0xff));
-
- DEBPROTO(printk(KERN_DEBUG " 0x%02x", indata & 0xff));
- return (int) (indata & 0xff);
+ return indata;
}
/*
* 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_bit_data *adap, char* name) {
- int scl,sda;
-
- if (adap->getscl==NULL)
- printk(KERN_INFO "i2c-algo-bit.o: Testing SDA only, "
- "SCL is not readable.\n");
-
- sda=getsda(adap);
- scl=(adap->getscl==NULL?1:getscl(adap));
- printk(KERN_DEBUG "i2c-algo-bit.o: (0) scl=%d, sda=%d\n",scl,sda);
- if (!scl || !sda ) {
- printk(KERN_WARNING "i2c-algo-bit.o: %s seems to be busy.\n", name);
+static int test_bus(struct i2c_algo_bit_data *adap, char *name)
+{
+ int scl, sda;
+
+ if (adap->getscl == NULL)
+ pr_info("%s: Testing SDA only, SCL is not readable\n", name);
+
+ sda = getsda(adap);
+ scl = (adap->getscl == NULL) ? 1 : getscl(adap);
+ if (!scl || !sda) {
+ printk(KERN_WARNING "%s: bus seems to be busy\n", name);
goto bailout;
}
sdalo(adap);
- sda=getsda(adap);
- scl=(adap->getscl==NULL?1:getscl(adap));
- printk(KERN_DEBUG "i2c-algo-bit.o: (1) scl=%d, sda=%d\n",scl,sda);
- if ( 0 != sda ) {
- printk(KERN_WARNING "i2c-algo-bit.o: SDA stuck high!\n");
+ sda = getsda(adap);
+ scl = (adap->getscl == NULL) ? 1 : getscl(adap);
+ if (sda) {
+ printk(KERN_WARNING "%s: SDA stuck high!\n", name);
goto bailout;
}
- if ( 0 == scl ) {
- printk(KERN_WARNING "i2c-algo-bit.o: SCL unexpected low "
- "while pulling SDA low!\n");
+ if (!scl) {
+ printk(KERN_WARNING "%s: SCL unexpected low "
+ "while pulling SDA low!\n", name);
goto bailout;
- }
+ }
sdahi(adap);
- sda=getsda(adap);
- scl=(adap->getscl==NULL?1:getscl(adap));
- printk(KERN_DEBUG "i2c-algo-bit.o: (2) scl=%d, sda=%d\n",scl,sda);
- if ( 0 == sda ) {
- printk(KERN_WARNING "i2c-algo-bit.o: SDA stuck low!\n");
+ sda = getsda(adap);
+ scl = (adap->getscl == NULL) ? 1 : getscl(adap);
+ if (!sda) {
+ printk(KERN_WARNING "%s: SDA stuck low!\n", name);
goto bailout;
}
- if ( 0 == scl ) {
- printk(KERN_WARNING "i2c-algo-bit.o: SCL unexpected low "
- "while pulling SDA high!\n");
+ if (!scl) {
+ printk(KERN_WARNING "%s: SCL unexpected low "
+ "while pulling SDA high!\n", name);
goto bailout;
}
scllo(adap);
- sda=getsda(adap);
- scl=(adap->getscl==NULL?0:getscl(adap));
- printk(KERN_DEBUG "i2c-algo-bit.o: (3) scl=%d, sda=%d\n",scl,sda);
- if ( 0 != scl ) {
- printk(KERN_WARNING "i2c-algo-bit.o: SCL stuck high!\n");
+ sda = getsda(adap);
+ scl = (adap->getscl == NULL) ? 0 : getscl(adap);
+ if (scl) {
+ printk(KERN_WARNING "%s: SCL stuck high!\n", name);
goto bailout;
}
- if ( 0 == sda ) {
- printk(KERN_WARNING "i2c-algo-bit.o: SDA unexpected low "
- "while pulling SCL low!\n");
+ if (!sda) {
+ printk(KERN_WARNING "%s: SDA unexpected low "
+ "while pulling SCL low!\n", name);
goto bailout;
}
-
+
sclhi(adap);
- sda=getsda(adap);
- scl=(adap->getscl==NULL?1:getscl(adap));
- printk(KERN_DEBUG "i2c-algo-bit.o: (4) scl=%d, sda=%d\n",scl,sda);
- if ( 0 == scl ) {
- printk(KERN_WARNING "i2c-algo-bit.o: SCL stuck low!\n");
+ sda = getsda(adap);
+ scl = (adap->getscl == NULL) ? 1 : getscl(adap);
+ if (!scl) {
+ printk(KERN_WARNING "%s: SCL stuck low!\n", name);
goto bailout;
}
- if ( 0 == sda ) {
- printk(KERN_WARNING "i2c-algo-bit.o: SDA unexpected low "
- "while pulling SCL high!\n");
+ if (!sda) {
+ printk(KERN_WARNING "%s: SDA unexpected low "
+ "while pulling SCL high!\n", name);
goto bailout;
}
- printk(KERN_INFO "i2c-algo-bit.o: %s passed test.\n",name);
+ pr_info("%s: Test OK\n", name);
return 0;
bailout:
sdahi(adap);
unsigned char addr, int retries)
{
struct i2c_algo_bit_data *adap = i2c_adap->algo_data;
- int i,ret = -1;
- for (i=0;i<=retries;i++) {
- ret = i2c_outb(i2c_adap,addr);
+ int i, ret = -1;
+
+ for (i = 0; i <= retries; i++) {
+ ret = i2c_outb(i2c_adap, addr);
if (ret == 1 || i == retries)
break;
+ bit_dbg(3, &i2c_adap->dev, "emitting stop condition\n");
i2c_stop(adap);
- udelay(5/*adap->udelay*/);
- i2c_start(adap);
udelay(adap->udelay);
+ yield();
+ bit_dbg(3, &i2c_adap->dev, "emitting start condition\n");
+ i2c_start(adap);
}
- DEB2(if (i)
- printk(KERN_DEBUG "i2c-algo-bit.o: Used %d tries to %s client at 0x%02x : %s\n",
- i+1, addr & 1 ? "read" : "write", addr>>1,
- ret==1 ? "success" : ret==0 ? "no ack" : "failed, timeout?" )
- );
+ if (i && ret)
+ bit_dbg(1, &i2c_adap->dev, "Used %d tries to %s client at "
+ "0x%02x: %s\n", i + 1,
+ addr & 1 ? "read from" : "write to", addr >> 1,
+ ret == 1 ? "success" : "failed, timeout?");
return ret;
}
static int sendbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg)
{
- char c;
- const char *temp = msg->buf;
+ const unsigned char *temp = msg->buf;
int count = msg->len;
- unsigned short nak_ok = msg->flags & I2C_M_IGNORE_NAK;
+ unsigned short nak_ok = msg->flags & I2C_M_IGNORE_NAK;
int retval;
- int wrcount=0;
+ int wrcount = 0;
while (count > 0) {
- c = *temp;
- DEB2(dev_dbg(&i2c_adap->dev, "sendbytes: writing %2.2X\n", c&0xff));
- retval = i2c_outb(i2c_adap,c);
- if ((retval>0) || (nak_ok && (retval==0))) { /* ok or ignored NAK */
- count--;
+ retval = i2c_outb(i2c_adap, *temp);
+
+ /* OK/ACK; or ignored NAK */
+ if ((retval > 0) || (nak_ok && (retval == 0))) {
+ count--;
temp++;
wrcount++;
- } else { /* arbitration or no acknowledge */
- dev_err(&i2c_adap->dev, "sendbytes: error - bailout.\n");
- return (retval<0)? retval : -EFAULT;
- /* got a better one ?? */
+
+ /* A slave NAKing the master means the slave didn't like
+ * something about the data it saw. For example, maybe
+ * the SMBus PEC was wrong.
+ */
+ } else if (retval == 0) {
+ dev_err(&i2c_adap->dev, "sendbytes: NAK bailout.\n");
+ return -EIO;
+
+ /* Timeout; or (someday) lost arbitration
+ *
+ * FIXME Lost ARB implies retrying the transaction from
+ * the first message, after the "winning" master issues
+ * its STOP. As a rule, upper layer code has no reason
+ * to know or care about this ... it is *NOT* an error.
+ */
+ } else {
+ dev_err(&i2c_adap->dev, "sendbytes: error %d\n",
+ retval);
+ return retval;
}
}
return wrcount;
}
+static int acknak(struct i2c_adapter *i2c_adap, int is_ack)
+{
+ struct i2c_algo_bit_data *adap = i2c_adap->algo_data;
+
+ /* assert: sda is high */
+ if (is_ack) /* send ack */
+ setsda(adap, 0);
+ udelay((adap->udelay + 1) / 2);
+ if (sclhi(adap) < 0) { /* timeout */
+ dev_err(&i2c_adap->dev, "readbytes: ack/nak timeout\n");
+ return -ETIMEDOUT;
+ }
+ scllo(adap);
+ return 0;
+}
+
static int readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg)
{
int inval;
- int rdcount=0; /* counts bytes read */
- struct i2c_algo_bit_data *adap = i2c_adap->algo_data;
- char *temp = msg->buf;
+ int rdcount = 0; /* counts bytes read */
+ unsigned char *temp = msg->buf;
int count = msg->len;
+ const unsigned flags = msg->flags;
while (count > 0) {
inval = i2c_inb(i2c_adap);
- if (inval>=0) {
+ if (inval >= 0) {
*temp = inval;
rdcount++;
} else { /* read timed out */
- printk(KERN_ERR "i2c-algo-bit.o: readbytes: i2c_inb timed out.\n");
break;
}
temp++;
count--;
- if (msg->flags & I2C_M_NO_RD_ACK)
- continue;
-
- if ( count > 0 ) { /* send ack */
- sdalo(adap);
- DEBPROTO(printk(" Am "));
- } else {
- sdahi(adap); /* neg. ack on last byte */
- DEBPROTO(printk(" NAm "));
- }
- if (sclhi(adap)<0) { /* timeout */
- sdahi(adap);
- printk(KERN_ERR "i2c-algo-bit.o: readbytes: Timeout at ack\n");
- return -ETIMEDOUT;
- };
- scllo(adap);
- sdahi(adap);
-
/* Some SMBus transactions require that we receive the
transaction length as the first read byte. */
- if (rdcount == 1 && (msg->flags & I2C_M_RECV_LEN)) {
+ if (rdcount == 1 && (flags & I2C_M_RECV_LEN)) {
if (inval <= 0 || inval > I2C_SMBUS_BLOCK_MAX) {
- printk(KERN_ERR "i2c-algo-bit: readbytes: "
- "invalid block length (%d)\n", inval);
+ if (!(flags & I2C_M_NO_RD_ACK))
+ acknak(i2c_adap, 0);
+ dev_err(&i2c_adap->dev, "readbytes: invalid "
+ "block length (%d)\n", inval);
return -EREMOTEIO;
}
/* The original count value accounts for the extra
count += inval;
msg->len += inval;
}
+
+ bit_dbg(2, &i2c_adap->dev, "readbytes: 0x%02x %s\n",
+ inval,
+ (flags & I2C_M_NO_RD_ACK)
+ ? "(no ack/nak)"
+ : (count ? "A" : "NA"));
+
+ if (!(flags & I2C_M_NO_RD_ACK)) {
+ inval = acknak(i2c_adap, count);
+ if (inval < 0)
+ return inval;
+ }
}
return rdcount;
}
* returns:
* 0 everything went okay, the chip ack'ed, or IGNORE_NAK flag was set
* -x an error occurred (like: -EREMOTEIO if the device did not answer, or
- * -ETIMEDOUT, for example if the lines are stuck...)
+ * -ETIMEDOUT, for example if the lines are stuck...)
*/
static int bit_doAddress(struct i2c_adapter *i2c_adap, struct i2c_msg *msg)
{
int ret, retries;
retries = nak_ok ? 0 : i2c_adap->retries;
-
- if ( (flags & I2C_M_TEN) ) {
+
+ if (flags & I2C_M_TEN) {
/* a ten bit address */
- addr = 0xf0 | (( msg->addr >> 7) & 0x03);
- DEB2(printk(KERN_DEBUG "addr0: %d\n",addr));
+ addr = 0xf0 | ((msg->addr >> 7) & 0x03);
+ bit_dbg(2, &i2c_adap->dev, "addr0: %d\n", addr);
/* try extended address code...*/
ret = try_address(i2c_adap, addr, retries);
if ((ret != 1) && !nak_ok) {
- printk(KERN_ERR "died at extended address code.\n");
+ dev_err(&i2c_adap->dev,
+ "died at extended address code\n");
return -EREMOTEIO;
}
/* the remaining 8 bit address */
- ret = i2c_outb(i2c_adap,msg->addr & 0x7f);
+ ret = i2c_outb(i2c_adap, msg->addr & 0x7f);
if ((ret != 1) && !nak_ok) {
/* the chip did not ack / xmission error occurred */
- printk(KERN_ERR "died at 2nd address code.\n");
+ dev_err(&i2c_adap->dev, "died at 2nd address code\n");
return -EREMOTEIO;
}
- if ( flags & I2C_M_RD ) {
+ if (flags & I2C_M_RD) {
+ bit_dbg(3, &i2c_adap->dev, "emitting repeated "
+ "start condition\n");
i2c_repstart(adap);
/* okay, now switch into reading mode */
addr |= 0x01;
ret = try_address(i2c_adap, addr, retries);
- if ((ret!=1) && !nak_ok) {
- printk(KERN_ERR "died at extended address code.\n");
+ if ((ret != 1) && !nak_ok) {
+ dev_err(&i2c_adap->dev,
+ "died at repeated address code\n");
return -EREMOTEIO;
}
}
} else { /* normal 7bit address */
- addr = ( msg->addr << 1 );
- if (flags & I2C_M_RD )
+ addr = msg->addr << 1;
+ if (flags & I2C_M_RD)
addr |= 1;
- if (flags & I2C_M_REV_DIR_ADDR )
+ if (flags & I2C_M_REV_DIR_ADDR)
addr ^= 1;
ret = try_address(i2c_adap, addr, retries);
- if ((ret!=1) && !nak_ok)
+ if ((ret != 1) && !nak_ok)
return -EREMOTEIO;
}
{
struct i2c_msg *pmsg;
struct i2c_algo_bit_data *adap = i2c_adap->algo_data;
-
- int i,ret;
+ int i, ret;
unsigned short nak_ok;
+ bit_dbg(3, &i2c_adap->dev, "emitting start condition\n");
i2c_start(adap);
- for (i=0;i<num;i++) {
+ for (i = 0; i < num; i++) {
pmsg = &msgs[i];
- nak_ok = pmsg->flags & I2C_M_IGNORE_NAK;
+ nak_ok = pmsg->flags & I2C_M_IGNORE_NAK;
if (!(pmsg->flags & I2C_M_NOSTART)) {
if (i) {
+ bit_dbg(3, &i2c_adap->dev, "emitting "
+ "repeated start condition\n");
i2c_repstart(adap);
}
ret = bit_doAddress(i2c_adap, pmsg);
if ((ret != 0) && !nak_ok) {
- DEB2(printk(KERN_DEBUG "i2c-algo-bit.o: NAK from device addr %2.2x msg #%d\n"
- ,msgs[i].addr,i));
+ bit_dbg(1, &i2c_adap->dev, "NAK from "
+ "device addr 0x%02x msg #%d\n",
+ msgs[i].addr, i);
goto bailout;
}
}
- if (pmsg->flags & I2C_M_RD ) {
+ if (pmsg->flags & I2C_M_RD) {
/* read bytes into buffer*/
ret = readbytes(i2c_adap, pmsg);
- DEB2(printk(KERN_DEBUG "i2c-algo-bit.o: read %d bytes.\n",ret));
+ if (ret >= 1)
+ bit_dbg(2, &i2c_adap->dev, "read %d byte%s\n",
+ ret, ret == 1 ? "" : "s");
if (ret < pmsg->len) {
if (ret >= 0)
ret = -EREMOTEIO;
} else {
/* write bytes from buffer */
ret = sendbytes(i2c_adap, pmsg);
- DEB2(printk(KERN_DEBUG "i2c-algo-bit.o: wrote %d bytes.\n",ret));
+ if (ret >= 1)
+ bit_dbg(2, &i2c_adap->dev, "wrote %d byte%s\n",
+ ret, ret == 1 ? "" : "s");
if (ret < pmsg->len) {
if (ret >= 0)
ret = -EREMOTEIO;
ret = i;
bailout:
+ bit_dbg(3, &i2c_adap->dev, "emitting stop condition\n");
i2c_stop(adap);
return ret;
}
static u32 bit_func(struct i2c_adapter *adap)
{
- return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
I2C_FUNC_SMBUS_READ_BLOCK_DATA |
I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
I2C_FUNC_10BIT_ADDR | I2C_FUNC_PROTOCOL_MANGLING;
.functionality = bit_func,
};
-/*
- * registering functions to load algorithms at runtime
+/*
+ * registering functions to load algorithms at runtime
*/
static int i2c_bit_prepare_bus(struct i2c_adapter *adap)
{
if (bit_test) {
int ret = test_bus(bit_adap, adap->name);
- if (ret<0)
+ if (ret < 0)
return -ENODEV;
}
- DEB2(dev_dbg(&adap->dev, "hw routines registered.\n"));
-
/* register new adapter to i2c module... */
adap->algo = &i2c_bit_algo;
MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>");
MODULE_DESCRIPTION("I2C-Bus bit-banging algorithm");
MODULE_LICENSE("GPL");
-
-module_param(bit_test, bool, 0);
-module_param(i2c_debug, int, S_IRUGO | S_IWUSR);
-
-MODULE_PARM_DESC(bit_test, "Test the lines of the bus to see if it is stuck");
-MODULE_PARM_DESC(i2c_debug,
- "debug level - 0 off; 1 normal; 2,3 more verbose; 9 bit-protocol");
git.openpandora.org / pandora-kernel.git / blobdiff