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Commit 0c168ceb authored by Roel Kluin's avatar Roel Kluin Committed by Jean Delvare
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i2c-algo-pcf: Style cleanups 

cleanup whitespace, fix comments and remove the unused STUB_I2C.
Signed-off-by: default avatarRoel Kluin <roel.kluin@gmail.com>
Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
Acked-by: default avatarEric Brower <ebrower@gmail.com>
parent 781b8a2a
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Showing with 115 additions and 135 deletions
drivers/i2c/algos/i2c-algo-pcf.c
View file @ 0c168ceb
/* ------------------------------------------------------------------------- */
/* i2c-algo-pcf.c i2c driver algorithms for PCF8584 adapters */
/* ------------------------------------------------------------------------- */
/* 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> */
/* Partially rewriten by Oleg I. Vdovikin <vdovikin@jscc.ru> to handle multiple
messages, proper stop/repstart signaling during receive,
added detect code */
/*
* i2c-algo-pcf.c i2c driver algorithms for PCF8584 adapters
*
* 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>
*
* Partially rewriten by Oleg I. Vdovikin <vdovikin@jscc.ru> to handle multiple
* messages, proper stop/repstart signaling during receive, added detect code
*/
#include <linux/kernel.h>
#include <linux/module.h>
......@@ -38,17 +37,18 @@
#include "i2c-algo-pcf.h"
#define DEB2(x) if (i2c_debug>=2) x
#define DEB3(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 */
#define DEB2(x) if (i2c_debug >= 2) x
#define DEB3(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 */
#define DEF_TIMEOUT 16
/* module parameters:
/*
* module parameters:
*/
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 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_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 "));
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 "));
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"));
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
"i2c-algo-pcf.o: lost arbitration (CSR 0x%02x)\n",
*status));
/* Cleanup from LAB -- reset and enable ESO.
*status));
/*
* Cleanup from LAB -- reset and enable ESO.
* This resets the PCF8584; since we've lost the bus, no
* further attempts should be made by callers to clean up
* (no i2c_stop() etc.)
*/
set_pcf(adap, 1, I2C_PCF_PIN);
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
* work properly until the next START is seen.
* 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)));
}
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 status;
status = get_pcf(adap, 1);
#ifndef STUB_I2C
while (timeout-- && !(status & I2C_PCF_BB)) {
udelay(100); /* wait for 100 us */
status = get_pcf(adap, 1);
}
#endif
if (timeout <= 0) {
if (timeout <= 0)
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;
*status = get_pcf(adap, 1);
#ifndef STUB_I2C
while (timeout-- && (*status & I2C_PCF_PIN)) {
adap->waitforpin(adap->data);
*status = get_pcf(adap, 1);
}
if (*status & I2C_PCF_LAB) {
handle_lab(adap, status);
return(-EINTR);
return -EINTR;
}
#endif
if (timeout <= 0)
return(-1);
return -1;
else
return(0);
return 0;
}
/*
/*
* This should perform the 'PCF8584 initialization sequence' as described
* in the Philips IC12 data book (1995, Aug 29).
* 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;
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 */
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)) {
DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't select S0 (0x%02x).\n", temp));
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));
/* check it's really written */
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;
}
/* S1=0xA0, next byte in S2 */
/* S1=0xA0, next byte in S2 */
set_pcf(adap, 1, I2C_PCF_PIN | I2C_PCF_ES1);
/* check to see S2 now selected */
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;
}
/* load clock register S2 */
/* load clock register S2 */
i2c_outb(adap, get_clock(adap));
/* check it's really written, the only 5 lowest bits does matter */
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;
}
/* Enable serial interface, idle, S0 selected */
/* Enable serial interface, idle, S0 selected */
set_pcf(adap, 1, I2C_PCF_IDLE);
/* 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));
return -ENXIO;
}
printk(KERN_DEBUG "i2c-algo-pcf.o: detected and initialized PCF8584.\n");
return 0;
}
/* ----- Utility functions
*/
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;
int wrcount, status, timeout;
for (wrcount=0; wrcount<count; ++wrcount) {
DEB2(dev_dbg(&i2c_adap->dev, "i2c_write: writing %2.2X\n",
buf[wrcount]&0xff));
buf[wrcount] & 0xff));
i2c_outb(adap, buf[wrcount]);
timeout = wait_for_pin(adap, &status);
if (timeout) {
if (timeout == -EINTR) {
/* arbitration lost */
return -EINTR;
}
if (timeout == -EINTR)
return -EINTR; /* arbitration lost */
i2c_stop(adap);
dev_err(&i2c_adap->dev, "i2c_write: error - timeout.\n");
return -EREMOTEIO; /* got a better one ?? */
}
#ifndef STUB_I2C
if (status & I2C_PCF_LRB) {
i2c_stop(adap);
dev_err(&i2c_adap->dev, "i2c_write: error - no ack.\n");
return -EREMOTEIO; /* got a better one ?? */
}
#endif
}
if (last) {
if (last)
i2c_stop(adap);
}
else {
else
i2c_repstart(adap);
}
return (wrcount);
return wrcount;
}
static int pcf_readbytes(struct i2c_adapter *i2c_adap, char *buf,
int count, int last)
int count, int last)
{
int i, status;
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++) {
if ((wfp = wait_for_pin(adap, &status))) {
if (wfp == -EINTR) {
/* arbitration lost */
return -EINTR;
}
if (wfp == -EINTR)
return -EINTR; /* arbitration lost */
i2c_stop(adap);
dev_err(&i2c_adap->dev, "pcf_readbytes timed out.\n");
return (-1);
return -1;
}
#ifndef STUB_I2C
if ((status & I2C_PCF_LRB) && (i != count)) {
i2c_stop(adap);
dev_err(&i2c_adap->dev, "i2c_read: i2c_inb, No ack.\n");
return (-1);
return -1;
}
#endif
if (i == count - 1) {
set_pcf(adap, 1, I2C_PCF_ESO);
} else
if (i == count) {
if (last) {
} else if (i == count) {
if (last)
i2c_stop(adap);
} else {
else
i2c_repstart(adap);
}
};
}
if (i) {
if (i)
buf[i - 1] = i2c_inb(adap);
} else {
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,
struct i2c_msg *msgs,
struct i2c_msg *msgs,
int num)
{
struct i2c_algo_pcf_data *adap = i2c_adap->algo_data;
struct i2c_msg *pmsg;
int i;
int ret=0, timeout, status;
if (adap->xfer_begin)
adap->xfer_begin(adap->data);
......@@ -338,25 +324,24 @@ static int pcf_xfer(struct i2c_adapter *i2c_adap,
timeout = wait_for_bb(adap);
if (timeout) {
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;
goto out;
}
for (i = 0;ret >= 0 && i < num; i++) {
pmsg = &msgs[i];
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->len, pmsg->addr, i + 1, num);)
pmsg->len, pmsg->addr, i + 1, num);)
ret = pcf_doAddress(adap, pmsg);
/* Send START */
if (i == 0) {
i2c_start(adap);
}
if (i == 0)
i2c_start(adap);
/* Wait for PIN (pending interrupt NOT) */
timeout = wait_for_pin(adap, &status);
if (timeout) {
......@@ -371,8 +356,7 @@ static int pcf_xfer(struct i2c_adapter *i2c_adap,
i = -EREMOTEIO;
goto out;
}
#ifndef STUB_I2C
/* Check LRB (last rcvd bit - slave ack) */
if (status & I2C_PCF_LRB) {
i2c_stop(adap);
......@@ -380,27 +364,24 @@ static int pcf_xfer(struct i2c_adapter *i2c_adap,
i = -EREMOTEIO;
goto out;
}
#endif
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);)
/* Read */
if (pmsg->flags & I2C_M_RD) {
/* read bytes into buffer*/
ret = pcf_readbytes(i2c_adap, pmsg->buf, pmsg->len,
(i + 1 == num));
(i + 1 == num));
if (ret != pmsg->len) {
DEB2(printk(KERN_DEBUG "i2c-algo-pcf.o: fail: "
"only read %d bytes.\n",ret));
} else {
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,
(i + 1 == num));
(i + 1 == num));
if (ret != pmsg->len) {
DEB2(printk(KERN_DEBUG "i2c-algo-pcf.o: fail: "
"only wrote %d bytes.\n",ret));
......@@ -413,24 +394,23 @@ static int pcf_xfer(struct i2c_adapter *i2c_adap,
out:
if (adap->xfer_end)
adap->xfer_end(adap->data);
return (i);
return i;
}
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;
}
/* -----exported algorithm data: ------------------------------------- */
/* exported algorithm data: */
static const struct i2c_algorithm pcf_algo = {
.master_xfer = pcf_xfer,
.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)
{
......@@ -458,4 +438,4 @@ MODULE_LICENSE("GPL");
module_param(i2c_debug, int, S_IRUGO | S_IWUSR);
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");
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