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Diffstat (limited to 'drivers/i2c/algos/i2c-algo-pcf.c')
-rw-r--r--drivers/i2c/algos/i2c-algo-pcf.c135
1 files changed, 31 insertions, 104 deletions
diff --git a/drivers/i2c/algos/i2c-algo-pcf.c b/drivers/i2c/algos/i2c-algo-pcf.c
index 5c2379522aa9..a87ecea7f510 100644
--- a/drivers/i2c/algos/i2c-algo-pcf.c
+++ b/drivers/i2c/algos/i2c-algo-pcf.c
@@ -1,24 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/*
* 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., 51 Franklin Street, Fifth Floor, Boston,
- * MA 02110-1301 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>
@@ -30,24 +16,15 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/delay.h>
-#include <linux/init.h>
#include <linux/errno.h>
#include <linux/i2c.h>
#include <linux/i2c-algo-pcf.h>
+#include <linux/string_choices.h>
#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 DEF_TIMEOUT 16
-/*
- * module parameters:
- */
-static int i2c_debug;
-
/* setting states on the bus with the right timing: */
#define set_pcf(adap, ctl, val) adap->setpcf(adap->data, ctl, val)
@@ -61,27 +38,21 @@ static int i2c_debug;
static void i2c_start(struct i2c_algo_pcf_data *adap)
{
- DEBPROTO(printk(KERN_DEBUG "S "));
set_pcf(adap, 1, I2C_PCF_START);
}
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)
{
- DEBPROTO(printk("P\n"));
set_pcf(adap, 1, I2C_PCF_STOP);
}
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.
* This resets the PCF8584; since we've lost the bus, no
@@ -102,9 +73,6 @@ static void handle_lab(struct i2c_algo_pcf_data *adap, const int *status)
if (adap->lab_mdelay)
mdelay(adap->lab_mdelay);
- DEB2(printk(KERN_INFO
- "i2c-algo-pcf.o: reset LAB condition (CSR 0x%02x)\n",
- get_pcf(adap, 1)));
}
static int wait_for_bb(struct i2c_algo_pcf_data *adap)
@@ -161,56 +129,48 @@ static int wait_for_pin(struct i2c_algo_pcf_data *adap, int *status)
*
* vdovikin: added detect code for PCF8584
*/
-static int pcf_init_8584 (struct i2c_algo_pcf_data *adap)
+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)));
-
/* 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
*/
- 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));
+ temp = get_pcf(adap, 1);
+ if ((temp & 0x7f) != 0)
return -ENXIO; /* definitely not PCF8584 */
- }
/* 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)) {
- DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't set S0 (0x%02x).\n", temp));
+ temp = i2c_inb(adap);
+ if (temp != get_own(adap))
return -ENXIO;
- }
/* 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) {
- DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't select S2 (0x%02x).\n", temp));
+ temp = get_pcf(adap, 1);
+ if ((temp & 0x7f) != I2C_PCF_ES1)
return -ENXIO;
- }
/* 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)) {
- DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't set S2 (0x%02x).\n", temp));
+ temp = i2c_inb(adap);
+ if ((temp & 0x1f) != get_clock(adap))
return -ENXIO;
- }
/* 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 */
- if ((temp = get_pcf(adap, 1)) != (I2C_PCF_PIN | I2C_PCF_BB)) {
- DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't select S1` (0x%02x).\n", temp));
+ temp = get_pcf(adap, 1);
+ if (temp != (I2C_PCF_PIN | I2C_PCF_BB))
return -ENXIO;
- }
printk(KERN_DEBUG "i2c-algo-pcf.o: detected and initialized PCF8584.\n");
@@ -223,9 +183,7 @@ static int pcf_sendbytes(struct i2c_adapter *i2c_adap, const char *buf,
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));
+ for (wrcount = 0; wrcount < count; ++wrcount) {
i2c_outb(adap, buf[wrcount]);
timeout = wait_for_pin(adap, &status);
if (timeout) {
@@ -260,7 +218,8 @@ static int pcf_readbytes(struct i2c_adapter *i2c_adap, char *buf,
/* increment number of bytes to read by one -- read dummy byte */
for (i = 0; i <= count; i++) {
- if ((wfp = wait_for_pin(adap, &status))) {
+ wfp = wait_for_pin(adap, &status);
+ if (wfp) {
if (wfp == -EINTR)
return -EINTR; /* arbitration lost */
@@ -294,20 +253,14 @@ static int pcf_readbytes(struct i2c_adapter *i2c_adap, char *buf,
}
-static int pcf_doAddress(struct i2c_algo_pcf_data *adap,
+static void pcf_send_address(struct i2c_algo_pcf_data *adap,
struct i2c_msg *msg)
{
- unsigned short flags = msg->flags;
- unsigned char addr;
+ unsigned char addr = i2c_8bit_addr_from_msg(msg);
- addr = msg->addr << 1;
- if (flags & I2C_M_RD)
- addr |= 1;
- if (flags & I2C_M_REV_DIR_ADDR)
+ if (msg->flags & I2C_M_REV_DIR_ADDR)
addr ^= 1;
i2c_outb(adap, addr);
-
- return 0;
}
static int pcf_xfer(struct i2c_adapter *i2c_adap,
@@ -317,7 +270,7 @@ static int pcf_xfer(struct i2c_adapter *i2c_adap,
struct i2c_algo_pcf_data *adap = i2c_adap->algo_data;
struct i2c_msg *pmsg;
int i;
- int ret=0, timeout, status;
+ int timeout, status;
if (adap->xfer_begin)
adap->xfer_begin(adap->data);
@@ -325,20 +278,15 @@ static int pcf_xfer(struct i2c_adapter *i2c_adap,
/* Check for bus busy */
timeout = wait_for_bb(adap);
if (timeout) {
- DEB2(printk(KERN_ERR "i2c-algo-pcf.o: "
- "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);)
+ for (i = 0; i < num; i++) {
+ int ret;
- ret = pcf_doAddress(adap, pmsg);
+ pmsg = &msgs[i];
+ pcf_send_address(adap, pmsg);
/* Send START */
if (i == 0)
@@ -353,8 +301,6 @@ static int pcf_xfer(struct i2c_adapter *i2c_adap,
goto out;
}
i2c_stop(adap);
- DEB2(printk(KERN_ERR "i2c-algo-pcf.o: Timeout waiting "
- "for PIN(1) in pcf_xfer\n");)
i = -EREMOTEIO;
goto out;
}
@@ -362,35 +308,21 @@ static int pcf_xfer(struct i2c_adapter *i2c_adap,
/* Check LRB (last rcvd bit - slave ack) */
if (status & I2C_PCF_LRB) {
i2c_stop(adap);
- DEB2(printk(KERN_ERR "i2c-algo-pcf.o: No LRB(1) in pcf_xfer\n");)
i = -EREMOTEIO;
goto out;
}
- 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);)
if (pmsg->flags & I2C_M_RD) {
ret = pcf_readbytes(i2c_adap, pmsg->buf, pmsg->len,
(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 {
ret = pcf_sendbytes(i2c_adap, pmsg->buf, pmsg->len,
(i + 1 == num));
-
- if (ret != pmsg->len) {
- DEB2(printk(KERN_DEBUG "i2c-algo-pcf.o: fail: "
- "only wrote %d bytes.\n",ret));
- } else {
- DEB2(printk(KERN_DEBUG "i2c-algo-pcf.o: wrote %d bytes.\n",ret));
- }
}
+
+ if (ret < 0)
+ goto out;
}
out:
@@ -407,8 +339,8 @@ static u32 pcf_func(struct i2c_adapter *adap)
/* exported algorithm data: */
static const struct i2c_algorithm pcf_algo = {
- .master_xfer = pcf_xfer,
- .functionality = pcf_func,
+ .xfer = pcf_xfer,
+ .functionality = pcf_func,
};
/*
@@ -419,12 +351,11 @@ int i2c_pcf_add_bus(struct i2c_adapter *adap)
struct i2c_algo_pcf_data *pcf_adap = adap->algo_data;
int rval;
- DEB2(dev_dbg(&adap->dev, "hw routines registered.\n"));
-
/* register new adapter to i2c module... */
adap->algo = &pcf_algo;
- if ((rval = pcf_init_8584(pcf_adap)))
+ rval = pcf_init_8584(pcf_adap);
+ if (rval)
return rval;
rval = i2c_add_adapter(adap);
@@ -436,7 +367,3 @@ EXPORT_SYMBOL(i2c_pcf_add_bus);
MODULE_AUTHOR("Hans Berglund <hb@spacetec.no>");
MODULE_DESCRIPTION("I2C-Bus PCF8584 algorithm");
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");
generated by cgit (git 2.34.1) at 2025-12-25 03:17:02 +0000