linux/drivers/media/pci/mantis/mantis_i2c.c
Lars-Peter Clausen bf51a8c5e0 i2c: Ignore return value of i2c_del_adapter()
i2c_del_adapter() always returns 0. So all checks testing whether it will be
non zero will always evaluate to false and the conditional code is dead code.
This patch updates all callers of i2c_del_mux_adapter() to ignore the return
value and assume that it will always succeed (which it will). In a subsequent
patch the return type of i2c_del_adapter() will be made void.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Ben Hutchings <bhutchings@solarflare.com>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-04-02 07:06:03 +02:00

269 lines
6.6 KiB
C

/*
Mantis PCI bridge driver
Copyright (C) Manu Abraham (abraham.manu@gmail.com)
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.
*/
#include <asm/io.h>
#include <linux/ioport.h>
#include <linux/pci.h>
#include <linux/i2c.h>
#include "dmxdev.h"
#include "dvbdev.h"
#include "dvb_demux.h"
#include "dvb_frontend.h"
#include "dvb_net.h"
#include "mantis_common.h"
#include "mantis_reg.h"
#include "mantis_i2c.h"
#define TRIALS 10000
static int mantis_i2c_read(struct mantis_pci *mantis, const struct i2c_msg *msg)
{
u32 rxd, i, stat, trials;
dprintk(MANTIS_INFO, 0, " %s: Address=[0x%02x] <R>[ ",
__func__, msg->addr);
for (i = 0; i < msg->len; i++) {
rxd = (msg->addr << 25) | (1 << 24)
| MANTIS_I2C_RATE_3
| MANTIS_I2C_STOP
| MANTIS_I2C_PGMODE;
if (i == (msg->len - 1))
rxd &= ~MANTIS_I2C_STOP;
mmwrite(MANTIS_INT_I2CDONE, MANTIS_INT_STAT);
mmwrite(rxd, MANTIS_I2CDATA_CTL);
/* wait for xfer completion */
for (trials = 0; trials < TRIALS; trials++) {
stat = mmread(MANTIS_INT_STAT);
if (stat & MANTIS_INT_I2CDONE)
break;
}
dprintk(MANTIS_TMG, 0, "I2CDONE: trials=%d\n", trials);
/* wait for xfer completion */
for (trials = 0; trials < TRIALS; trials++) {
stat = mmread(MANTIS_INT_STAT);
if (stat & MANTIS_INT_I2CRACK)
break;
}
dprintk(MANTIS_TMG, 0, "I2CRACK: trials=%d\n", trials);
rxd = mmread(MANTIS_I2CDATA_CTL);
msg->buf[i] = (u8)((rxd >> 8) & 0xFF);
dprintk(MANTIS_INFO, 0, "%02x ", msg->buf[i]);
}
dprintk(MANTIS_INFO, 0, "]\n");
return 0;
}
static int mantis_i2c_write(struct mantis_pci *mantis, const struct i2c_msg *msg)
{
int i;
u32 txd = 0, stat, trials;
dprintk(MANTIS_INFO, 0, " %s: Address=[0x%02x] <W>[ ",
__func__, msg->addr);
for (i = 0; i < msg->len; i++) {
dprintk(MANTIS_INFO, 0, "%02x ", msg->buf[i]);
txd = (msg->addr << 25) | (msg->buf[i] << 8)
| MANTIS_I2C_RATE_3
| MANTIS_I2C_STOP
| MANTIS_I2C_PGMODE;
if (i == (msg->len - 1))
txd &= ~MANTIS_I2C_STOP;
mmwrite(MANTIS_INT_I2CDONE, MANTIS_INT_STAT);
mmwrite(txd, MANTIS_I2CDATA_CTL);
/* wait for xfer completion */
for (trials = 0; trials < TRIALS; trials++) {
stat = mmread(MANTIS_INT_STAT);
if (stat & MANTIS_INT_I2CDONE)
break;
}
dprintk(MANTIS_TMG, 0, "I2CDONE: trials=%d\n", trials);
/* wait for xfer completion */
for (trials = 0; trials < TRIALS; trials++) {
stat = mmread(MANTIS_INT_STAT);
if (stat & MANTIS_INT_I2CRACK)
break;
}
dprintk(MANTIS_TMG, 0, "I2CRACK: trials=%d\n", trials);
}
dprintk(MANTIS_INFO, 0, "]\n");
return 0;
}
static int mantis_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num)
{
int ret = 0, i = 0, trials;
u32 stat, data, txd;
struct mantis_pci *mantis;
struct mantis_hwconfig *config;
mantis = i2c_get_adapdata(adapter);
BUG_ON(!mantis);
config = mantis->hwconfig;
BUG_ON(!config);
dprintk(MANTIS_DEBUG, 1, "Messages:%d", num);
mutex_lock(&mantis->i2c_lock);
while (i < num) {
/* Byte MODE */
if ((config->i2c_mode & MANTIS_BYTE_MODE) &&
((i + 1) < num) &&
(msgs[i].len < 2) &&
(msgs[i + 1].len < 2) &&
(msgs[i + 1].flags & I2C_M_RD)) {
dprintk(MANTIS_DEBUG, 0, " Byte MODE:\n");
/* Read operation */
txd = msgs[i].addr << 25 | (0x1 << 24)
| (msgs[i].buf[0] << 16)
| MANTIS_I2C_RATE_3;
mmwrite(txd, MANTIS_I2CDATA_CTL);
/* wait for xfer completion */
for (trials = 0; trials < TRIALS; trials++) {
stat = mmread(MANTIS_INT_STAT);
if (stat & MANTIS_INT_I2CDONE)
break;
}
/* check for xfer completion */
if (stat & MANTIS_INT_I2CDONE) {
/* check xfer was acknowledged */
if (stat & MANTIS_INT_I2CRACK) {
data = mmread(MANTIS_I2CDATA_CTL);
msgs[i + 1].buf[0] = (data >> 8) & 0xff;
dprintk(MANTIS_DEBUG, 0, " Byte <%d> RXD=0x%02x [%02x]\n", 0x0, data, msgs[i + 1].buf[0]);
} else {
/* I/O error */
dprintk(MANTIS_ERROR, 1, " I/O error, LINE:%d", __LINE__);
ret = -EIO;
break;
}
} else {
/* I/O error */
dprintk(MANTIS_ERROR, 1, " I/O error, LINE:%d", __LINE__);
ret = -EIO;
break;
}
i += 2; /* Write/Read operation in one go */
}
if (i < num) {
if (msgs[i].flags & I2C_M_RD)
ret = mantis_i2c_read(mantis, &msgs[i]);
else
ret = mantis_i2c_write(mantis, &msgs[i]);
i++;
if (ret < 0)
goto bail_out;
}
}
mutex_unlock(&mantis->i2c_lock);
return num;
bail_out:
mutex_unlock(&mantis->i2c_lock);
return ret;
}
static u32 mantis_i2c_func(struct i2c_adapter *adapter)
{
return I2C_FUNC_SMBUS_EMUL;
}
static struct i2c_algorithm mantis_algo = {
.master_xfer = mantis_i2c_xfer,
.functionality = mantis_i2c_func,
};
int mantis_i2c_init(struct mantis_pci *mantis)
{
u32 intstat, intmask;
struct i2c_adapter *i2c_adapter = &mantis->adapter;
struct pci_dev *pdev = mantis->pdev;
init_waitqueue_head(&mantis->i2c_wq);
mutex_init(&mantis->i2c_lock);
strncpy(i2c_adapter->name, "Mantis I2C", sizeof(i2c_adapter->name));
i2c_set_adapdata(i2c_adapter, mantis);
i2c_adapter->owner = THIS_MODULE;
i2c_adapter->algo = &mantis_algo;
i2c_adapter->algo_data = NULL;
i2c_adapter->timeout = 500;
i2c_adapter->retries = 3;
i2c_adapter->dev.parent = &pdev->dev;
mantis->i2c_rc = i2c_add_adapter(i2c_adapter);
if (mantis->i2c_rc < 0)
return mantis->i2c_rc;
dprintk(MANTIS_DEBUG, 1, "Initializing I2C ..");
intstat = mmread(MANTIS_INT_STAT);
intmask = mmread(MANTIS_INT_MASK);
mmwrite(intstat, MANTIS_INT_STAT);
dprintk(MANTIS_DEBUG, 1, "Disabling I2C interrupt");
intmask = mmread(MANTIS_INT_MASK);
mmwrite((intmask & ~MANTIS_INT_I2CDONE), MANTIS_INT_MASK);
return 0;
}
EXPORT_SYMBOL_GPL(mantis_i2c_init);
int mantis_i2c_exit(struct mantis_pci *mantis)
{
u32 intmask;
dprintk(MANTIS_DEBUG, 1, "Disabling I2C interrupt");
intmask = mmread(MANTIS_INT_MASK);
mmwrite((intmask & ~MANTIS_INT_I2CDONE), MANTIS_INT_MASK);
dprintk(MANTIS_DEBUG, 1, "Removing I2C adapter");
i2c_del_adapter(&mantis->adapter);
return 0;
}
EXPORT_SYMBOL_GPL(mantis_i2c_exit);