hollalinux
/
linux-sg2042
mirror of https://github.com/sophgo/linux-riscv.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

i2c-algo-pcf: Style cleanups 

cleanup whitespace, fix comments and remove the unused STUB_I2C.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Eric Brower <ebrower@gmail.com>
This commit is contained in:
Roel Kluin 2009-03-28 21:34:42 +01:00 committed by Jean Delvare
parent 781b8a2a31
commit 0c168ceb9e
1 changed files with 117 additions and 137 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

254
drivers/i2c/algos/i2c-algo-pcf.c
View File

@ -1,31 +1,30 @@
/* ------------------------------------------------------------------------- */ /*
/* i2c-algo-pcf.c i2c driver algorithms for PCF8584 adapters */ * i2c-algo-pcf.c i2c driver algorithms for PCF8584 adapters
/* ------------------------------------------------------------------------- */ *
/* Copyright (C) 1995-1997 Simon G. Vogl * Copyright (C) 1995-1997 Simon G. Vogl
1998-2000 Hans Berglund * 1998-2000 Hans Berglund
*
This program is free software; you can redistribute it and/or modify * 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 * it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or * the Free Software Foundation; either version 2 of the License, or
(at your option) any later version. * (at your option) any later version.
*
This program is distributed in the hope that it will be useful, * This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of * but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details. * GNU General Public License for more details.
*
You should have received a copy of the GNU General Public License * You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software * 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 Kyösti Mälkki <kmalkki@cc.hut.fi> and
/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and * Frodo Looijaard <frodol@dds.nl>, and also from Martin Bailey
Frodo Looijaard <frodol@dds.nl> ,and also from Martin Bailey * <mbailey@littlefeet-inc.com>
<mbailey@littlefeet-inc.com> */ *
* Partially rewriten by Oleg I. Vdovikin <vdovikin@jscc.ru> to handle multiple
/* Partially rewriten by Oleg I. Vdovikin <vdovikin@jscc.ru> to handle multiple * messages, proper stop/repstart signaling during receive, added detect code
messages, proper stop/repstart signaling during receive, */
added detect code */
#include <linux/kernel.h> #include <linux/kernel.h>
#include <linux/module.h> #include <linux/module.h>
@ -38,17 +37,18 @@
#include "i2c-algo-pcf.h" #include "i2c-algo-pcf.h"
#define DEB2(x) if (i2c_debug>=2) x #define DEB2(x) if (i2c_debug >= 2) x
#define DEB3(x) if (i2c_debug>=3) x /* print several statistical values*/ #define DEB3(x) if (i2c_debug >= 3) x /* print several statistical values */
#define DEBPROTO(x) if (i2c_debug>=9) x; #define DEBPROTO(x) if (i2c_debug >= 9) x;
/* debug the protocol by showing transferred bits */ /* debug the protocol by showing transferred bits */
#define DEF_TIMEOUT 16 #define DEF_TIMEOUT 16
/* module parameters: /*
* module parameters:
*/ */
static int i2c_debug; static int i2c_debug;
/* --- setting states on the bus with the right timing: --------------- */ /* setting states on the bus with the right timing: */
#define set_pcf(adap, ctl, val) adap->setpcf(adap->data, ctl, val) #define set_pcf(adap, ctl, val) adap->setpcf(adap->data, ctl, val)
#define get_pcf(adap, ctl) adap->getpcf(adap->data, ctl) #define get_pcf(adap, ctl) adap->getpcf(adap->data, ctl)
@ -57,22 +57,21 @@ static int i2c_debug;
#define i2c_outb(adap, val) adap->setpcf(adap->data, 0, val) #define i2c_outb(adap, val) adap->setpcf(adap->data, 0, val)
#define i2c_inb(adap) adap->getpcf(adap->data, 0) #define i2c_inb(adap) adap->getpcf(adap->data, 0)
/* --- other auxiliary functions -------------------------------------- */ /* other auxiliary functions */
static void i2c_start(struct i2c_algo_pcf_data *adap) static void i2c_start(struct i2c_algo_pcf_data *adap)
{ {
DEBPROTO(printk("S ")); DEBPROTO(printk("S "));
set_pcf(adap, 1, I2C_PCF_START); set_pcf(adap, 1, I2C_PCF_START);
} }
static void i2c_repstart(struct i2c_algo_pcf_data *adap) static void i2c_repstart(struct i2c_algo_pcf_data *adap)
{ {
DEBPROTO(printk(" Sr ")); DEBPROTO(printk(" Sr "));
set_pcf(adap, 1, I2C_PCF_REPSTART); set_pcf(adap, 1, I2C_PCF_REPSTART);
} }
static void i2c_stop(struct i2c_algo_pcf_data *adap)
static void i2c_stop(struct i2c_algo_pcf_data *adap)
{ {
DEBPROTO(printk("P\n")); DEBPROTO(printk("P\n"));
set_pcf(adap, 1, I2C_PCF_STOP); set_pcf(adap, 1, I2C_PCF_STOP);
@ -82,17 +81,17 @@ static void handle_lab(struct i2c_algo_pcf_data *adap, const int *status)
{ {
DEB2(printk(KERN_INFO DEB2(printk(KERN_INFO
"i2c-algo-pcf.o: lost arbitration (CSR 0x%02x)\n", "i2c-algo-pcf.o: lost arbitration (CSR 0x%02x)\n",
*status)); *status));
/*
/* Cleanup from LAB -- reset and enable ESO. * Cleanup from LAB -- reset and enable ESO.
* This resets the PCF8584; since we've lost the bus, no * This resets the PCF8584; since we've lost the bus, no
* further attempts should be made by callers to clean up * further attempts should be made by callers to clean up
* (no i2c_stop() etc.) * (no i2c_stop() etc.)
*/ */
set_pcf(adap, 1, I2C_PCF_PIN); set_pcf(adap, 1, I2C_PCF_PIN);
set_pcf(adap, 1, I2C_PCF_ESO); set_pcf(adap, 1, I2C_PCF_ESO);
/*
/* We pause for a time period sufficient for any running * We pause for a time period sufficient for any running
* I2C transaction to complete -- the arbitration logic won't * I2C transaction to complete -- the arbitration logic won't
* work properly until the next START is seen. * work properly until the next START is seen.
* It is assumed the bus driver or client has set a proper value. * It is assumed the bus driver or client has set a proper value.
@ -108,48 +107,48 @@ static void handle_lab(struct i2c_algo_pcf_data *adap, const int *status)
get_pcf(adap, 1))); get_pcf(adap, 1)));
} }
static int wait_for_bb(struct i2c_algo_pcf_data *adap) { static int wait_for_bb(struct i2c_algo_pcf_data *adap)
{
int timeout = DEF_TIMEOUT; int timeout = DEF_TIMEOUT;
int status; int status;
status = get_pcf(adap, 1); status = get_pcf(adap, 1);
#ifndef STUB_I2C
while (timeout-- && !(status & I2C_PCF_BB)) { while (timeout-- && !(status & I2C_PCF_BB)) {
udelay(100); /* wait for 100 us */ udelay(100); /* wait for 100 us */
status = get_pcf(adap, 1); status = get_pcf(adap, 1);
} }
#endif
if (timeout <= 0) { if (timeout <= 0)
printk(KERN_ERR "Timeout waiting for Bus Busy\n"); printk(KERN_ERR "Timeout waiting for Bus Busy\n");
}
return timeout <= 0;
return (timeout<=0);
} }
static int wait_for_pin(struct i2c_algo_pcf_data *adap, int *status)
static int wait_for_pin(struct i2c_algo_pcf_data *adap, int *status) { {
int timeout = DEF_TIMEOUT; int timeout = DEF_TIMEOUT;
*status = get_pcf(adap, 1); *status = get_pcf(adap, 1);
#ifndef STUB_I2C
while (timeout-- && (*status & I2C_PCF_PIN)) { while (timeout-- && (*status & I2C_PCF_PIN)) {
adap->waitforpin(adap->data); adap->waitforpin(adap->data);
*status = get_pcf(adap, 1); *status = get_pcf(adap, 1);
} }
if (*status & I2C_PCF_LAB) { if (*status & I2C_PCF_LAB) {
handle_lab(adap, status); handle_lab(adap, status);
return(-EINTR); return -EINTR;
} }
#endif
if (timeout <= 0) if (timeout <= 0)
return(-1); return -1;
else else
return(0); return 0;
} }
/* /*
* This should perform the 'PCF8584 initialization sequence' as described * This should perform the 'PCF8584 initialization sequence' as described
* in the Philips IC12 data book (1995, Aug 29). * in the Philips IC12 data book (1995, Aug 29).
* There should be a 30 clock cycle wait after reset, I assume this * There should be a 30 clock cycle wait after reset, I assume this
@ -164,18 +163,21 @@ static int pcf_init_8584 (struct i2c_algo_pcf_data *adap)
{ {
unsigned char temp; unsigned char temp;
DEB3(printk(KERN_DEBUG "i2c-algo-pcf.o: PCF state 0x%02x\n", get_pcf(adap, 1))); DEB3(printk(KERN_DEBUG "i2c-algo-pcf.o: PCF state 0x%02x\n",
get_pcf(adap, 1)));
/* S1=0x80: S0 selected, serial interface off */ /* S1=0x80: S0 selected, serial interface off */
set_pcf(adap, 1, I2C_PCF_PIN); set_pcf(adap, 1, I2C_PCF_PIN);
/* check to see S1 now used as R/W ctrl - /*
PCF8584 does that when ESO is zero */ * check to see S1 now used as R/W ctrl -
* PCF8584 does that when ESO is zero
*/
if (((temp = get_pcf(adap, 1)) & 0x7f) != (0)) { if (((temp = get_pcf(adap, 1)) & 0x7f) != (0)) {
DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't select S0 (0x%02x).\n", temp)); DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't select S0 (0x%02x).\n", temp));
return -ENXIO; /* definetly not PCF8584 */ return -ENXIO; /* definetly not PCF8584 */
} }
/* load own address in S0, effective address is (own << 1) */ /* load own address in S0, effective address is (own << 1) */
i2c_outb(adap, get_own(adap)); i2c_outb(adap, get_own(adap));
/* check it's really written */ /* check it's really written */
if ((temp = i2c_inb(adap)) != get_own(adap)) { if ((temp = i2c_inb(adap)) != get_own(adap)) {
@ -183,7 +185,7 @@ static int pcf_init_8584 (struct i2c_algo_pcf_data *adap)
return -ENXIO; return -ENXIO;
} }
/* S1=0xA0, next byte in S2 */ /* S1=0xA0, next byte in S2 */
set_pcf(adap, 1, I2C_PCF_PIN | I2C_PCF_ES1); set_pcf(adap, 1, I2C_PCF_PIN | I2C_PCF_ES1);
/* check to see S2 now selected */ /* check to see S2 now selected */
if (((temp = get_pcf(adap, 1)) & 0x7f) != I2C_PCF_ES1) { if (((temp = get_pcf(adap, 1)) & 0x7f) != I2C_PCF_ES1) {
@ -191,7 +193,7 @@ static int pcf_init_8584 (struct i2c_algo_pcf_data *adap)
return -ENXIO; return -ENXIO;
} }
/* load clock register S2 */ /* load clock register S2 */
i2c_outb(adap, get_clock(adap)); i2c_outb(adap, get_clock(adap));
/* check it's really written, the only 5 lowest bits does matter */ /* check it's really written, the only 5 lowest bits does matter */
if (((temp = i2c_inb(adap)) & 0x1f) != get_clock(adap)) { if (((temp = i2c_inb(adap)) & 0x1f) != get_clock(adap)) {
@ -199,7 +201,7 @@ static int pcf_init_8584 (struct i2c_algo_pcf_data *adap)
return -ENXIO; return -ENXIO;
} }
/* Enable serial interface, idle, S0 selected */ /* Enable serial interface, idle, S0 selected */
set_pcf(adap, 1, I2C_PCF_IDLE); set_pcf(adap, 1, I2C_PCF_IDLE);
/* check to see PCF is really idled and we can access status register */ /* check to see PCF is really idled and we can access status register */
@ -207,57 +209,47 @@ static int pcf_init_8584 (struct i2c_algo_pcf_data *adap)
DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't select S1` (0x%02x).\n", temp)); DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't select S1` (0x%02x).\n", temp));
return -ENXIO; return -ENXIO;
} }
printk(KERN_DEBUG "i2c-algo-pcf.o: detected and initialized PCF8584.\n"); printk(KERN_DEBUG "i2c-algo-pcf.o: detected and initialized PCF8584.\n");
return 0; return 0;
} }
/* ----- Utility functions
*/
static int pcf_sendbytes(struct i2c_adapter *i2c_adap, const char *buf, static int pcf_sendbytes(struct i2c_adapter *i2c_adap, const char *buf,
int count, int last) int count, int last)
{ {
struct i2c_algo_pcf_data *adap = i2c_adap->algo_data; struct i2c_algo_pcf_data *adap = i2c_adap->algo_data;
int wrcount, status, timeout; int wrcount, status, timeout;
for (wrcount=0; wrcount<count; ++wrcount) { for (wrcount=0; wrcount<count; ++wrcount) {
DEB2(dev_dbg(&i2c_adap->dev, "i2c_write: writing %2.2X\n", DEB2(dev_dbg(&i2c_adap->dev, "i2c_write: writing %2.2X\n",
buf[wrcount]&0xff)); buf[wrcount] & 0xff));
i2c_outb(adap, buf[wrcount]); i2c_outb(adap, buf[wrcount]);
timeout = wait_for_pin(adap, &status); timeout = wait_for_pin(adap, &status);
if (timeout) { if (timeout) {
if (timeout == -EINTR) { if (timeout == -EINTR)
/* arbitration lost */ return -EINTR; /* arbitration lost */
return -EINTR;
}
i2c_stop(adap); i2c_stop(adap);
dev_err(&i2c_adap->dev, "i2c_write: error - timeout.\n"); dev_err(&i2c_adap->dev, "i2c_write: error - timeout.\n");
return -EREMOTEIO; /* got a better one ?? */ return -EREMOTEIO; /* got a better one ?? */
} }
#ifndef STUB_I2C
if (status & I2C_PCF_LRB) { if (status & I2C_PCF_LRB) {
i2c_stop(adap); i2c_stop(adap);
dev_err(&i2c_adap->dev, "i2c_write: error - no ack.\n"); dev_err(&i2c_adap->dev, "i2c_write: error - no ack.\n");
return -EREMOTEIO; /* got a better one ?? */ return -EREMOTEIO; /* got a better one ?? */
} }
#endif
} }
if (last) { if (last)
i2c_stop(adap); i2c_stop(adap);
} else
else {
i2c_repstart(adap); i2c_repstart(adap);
}
return (wrcount); return wrcount;
} }
static int pcf_readbytes(struct i2c_adapter *i2c_adap, char *buf, static int pcf_readbytes(struct i2c_adapter *i2c_adap, char *buf,
int count, int last) int count, int last)
{ {
int i, status; int i, status;
struct i2c_algo_pcf_data *adap = i2c_adap->algo_data; struct i2c_algo_pcf_data *adap = i2c_adap->algo_data;
@ -267,42 +259,36 @@ static int pcf_readbytes(struct i2c_adapter *i2c_adap, char *buf,
for (i = 0; i <= count; i++) { for (i = 0; i <= count; i++) {
if ((wfp = wait_for_pin(adap, &status))) { if ((wfp = wait_for_pin(adap, &status))) {
if (wfp == -EINTR) { if (wfp == -EINTR)
/* arbitration lost */ return -EINTR; /* arbitration lost */
return -EINTR;
}
i2c_stop(adap); i2c_stop(adap);
dev_err(&i2c_adap->dev, "pcf_readbytes timed out.\n"); dev_err(&i2c_adap->dev, "pcf_readbytes timed out.\n");
return (-1); return -1;
} }
#ifndef STUB_I2C
if ((status & I2C_PCF_LRB) && (i != count)) { if ((status & I2C_PCF_LRB) && (i != count)) {
i2c_stop(adap); i2c_stop(adap);
dev_err(&i2c_adap->dev, "i2c_read: i2c_inb, No ack.\n"); dev_err(&i2c_adap->dev, "i2c_read: i2c_inb, No ack.\n");
return (-1); return -1;
} }
#endif
if (i == count - 1) { if (i == count - 1) {
set_pcf(adap, 1, I2C_PCF_ESO); set_pcf(adap, 1, I2C_PCF_ESO);
} else } else if (i == count) {
if (i == count) { if (last)
if (last) {
i2c_stop(adap); i2c_stop(adap);
} else { else
i2c_repstart(adap); i2c_repstart(adap);
}
};
if (i) {
buf[i - 1] = i2c_inb(adap);
} else {
i2c_inb(adap); /* dummy read */
} }
if (i)
buf[i - 1] = i2c_inb(adap);
else
i2c_inb(adap); /* dummy read */
} }
return (i - 1); return i - 1;
} }
@ -323,14 +309,14 @@ static int pcf_doAddress(struct i2c_algo_pcf_data *adap,
} }
static int pcf_xfer(struct i2c_adapter *i2c_adap, static int pcf_xfer(struct i2c_adapter *i2c_adap,
struct i2c_msg *msgs, struct i2c_msg *msgs,
int num) int num)
{ {
struct i2c_algo_pcf_data *adap = i2c_adap->algo_data; struct i2c_algo_pcf_data *adap = i2c_adap->algo_data;
struct i2c_msg *pmsg; struct i2c_msg *pmsg;
int i; int i;
int ret=0, timeout, status; int ret=0, timeout, status;
if (adap->xfer_begin) if (adap->xfer_begin)
adap->xfer_begin(adap->data); adap->xfer_begin(adap->data);
@ -338,25 +324,24 @@ static int pcf_xfer(struct i2c_adapter *i2c_adap,
timeout = wait_for_bb(adap); timeout = wait_for_bb(adap);
if (timeout) { if (timeout) {
DEB2(printk(KERN_ERR "i2c-algo-pcf.o: " DEB2(printk(KERN_ERR "i2c-algo-pcf.o: "
"Timeout waiting for BB in pcf_xfer\n");) "Timeout waiting for BB in pcf_xfer\n");)
i = -EIO; i = -EIO;
goto out; goto out;
} }
for (i = 0;ret >= 0 && i < num; i++) { for (i = 0;ret >= 0 && i < num; i++) {
pmsg = &msgs[i]; pmsg = &msgs[i];
DEB2(printk(KERN_DEBUG "i2c-algo-pcf.o: Doing %s %d bytes to 0x%02x - %d of %d messages\n", DEB2(printk(KERN_DEBUG "i2c-algo-pcf.o: Doing %s %d bytes to 0x%02x - %d of %d messages\n",
pmsg->flags & I2C_M_RD ? "read" : "write", pmsg->flags & I2C_M_RD ? "read" : "write",
pmsg->len, pmsg->addr, i + 1, num);) pmsg->len, pmsg->addr, i + 1, num);)
ret = pcf_doAddress(adap, pmsg); ret = pcf_doAddress(adap, pmsg);
/* Send START */ /* Send START */
if (i == 0) { if (i == 0)
i2c_start(adap); i2c_start(adap);
}
/* Wait for PIN (pending interrupt NOT) */ /* Wait for PIN (pending interrupt NOT) */
timeout = wait_for_pin(adap, &status); timeout = wait_for_pin(adap, &status);
if (timeout) { if (timeout) {
@ -371,8 +356,7 @@ static int pcf_xfer(struct i2c_adapter *i2c_adap,
i = -EREMOTEIO; i = -EREMOTEIO;
goto out; goto out;
} }
#ifndef STUB_I2C
/* Check LRB (last rcvd bit - slave ack) */ /* Check LRB (last rcvd bit - slave ack) */
if (status & I2C_PCF_LRB) { if (status & I2C_PCF_LRB) {
i2c_stop(adap); i2c_stop(adap);
@ -380,27 +364,24 @@ static int pcf_xfer(struct i2c_adapter *i2c_adap,
i = -EREMOTEIO; i = -EREMOTEIO;
goto out; goto out;
} }
#endif
DEB3(printk(KERN_DEBUG "i2c-algo-pcf.o: Msg %d, addr=0x%x, flags=0x%x, len=%d\n", DEB3(printk(KERN_DEBUG "i2c-algo-pcf.o: Msg %d, addr=0x%x, flags=0x%x, len=%d\n",
i, msgs[i].addr, msgs[i].flags, msgs[i].len);) i, msgs[i].addr, msgs[i].flags, msgs[i].len);)
/* Read */
if (pmsg->flags & I2C_M_RD) { if (pmsg->flags & I2C_M_RD) {
/* read bytes into buffer*/
ret = pcf_readbytes(i2c_adap, pmsg->buf, pmsg->len, ret = pcf_readbytes(i2c_adap, pmsg->buf, pmsg->len,
(i + 1 == num)); (i + 1 == num));
if (ret != pmsg->len) { if (ret != pmsg->len) {
DEB2(printk(KERN_DEBUG "i2c-algo-pcf.o: fail: " DEB2(printk(KERN_DEBUG "i2c-algo-pcf.o: fail: "
"only read %d bytes.\n",ret)); "only read %d bytes.\n",ret));
} else { } else {
DEB2(printk(KERN_DEBUG "i2c-algo-pcf.o: read %d bytes.\n",ret)); DEB2(printk(KERN_DEBUG "i2c-algo-pcf.o: read %d bytes.\n",ret));
} }
} else { /* Write */ } else {
ret = pcf_sendbytes(i2c_adap, pmsg->buf, pmsg->len, ret = pcf_sendbytes(i2c_adap, pmsg->buf, pmsg->len,
(i + 1 == num)); (i + 1 == num));
if (ret != pmsg->len) { if (ret != pmsg->len) {
DEB2(printk(KERN_DEBUG "i2c-algo-pcf.o: fail: " DEB2(printk(KERN_DEBUG "i2c-algo-pcf.o: fail: "
"only wrote %d bytes.\n",ret)); "only wrote %d bytes.\n",ret));
@ -413,24 +394,23 @@ static int pcf_xfer(struct i2c_adapter *i2c_adap,
out: out:
if (adap->xfer_end) if (adap->xfer_end)
adap->xfer_end(adap->data); adap->xfer_end(adap->data);
return (i); return i;
} }
static u32 pcf_func(struct i2c_adapter *adap) static u32 pcf_func(struct i2c_adapter *adap)
{ {
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
I2C_FUNC_PROTOCOL_MANGLING; I2C_FUNC_PROTOCOL_MANGLING;
} }
/* -----exported algorithm data: ------------------------------------- */ /* exported algorithm data: */
static const struct i2c_algorithm pcf_algo = { static const struct i2c_algorithm pcf_algo = {
.master_xfer = pcf_xfer, .master_xfer = pcf_xfer,
.functionality = pcf_func, .functionality = pcf_func,
}; };
/* /*
* registering functions to load algorithms at runtime * registering functions to load algorithms at runtime
*/ */
int i2c_pcf_add_bus(struct i2c_adapter *adap) int i2c_pcf_add_bus(struct i2c_adapter *adap)
{ {
@ -458,4 +438,4 @@ MODULE_LICENSE("GPL");
module_param(i2c_debug, int, S_IRUGO | S_IWUSR); module_param(i2c_debug, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(i2c_debug, MODULE_PARM_DESC(i2c_debug,
"debug level - 0 off; 1 normal; 2,3 more verbose; 9 pcf-protocol"); "debug level - 0 off; 1 normal; 2,3 more verbose; 9 pcf-protocol");