- 根目录:
- drivers
- media
- pci
- cx23885
- cx23885-i2c.c
/*
* Driver for the Conexant CX23885 PCIe bridge
*
* Copyright (c) 2006 Steven Toth <stoth@linuxtv.org>
*
* 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 <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <asm/io.h>
#include "cx23885.h"
#include <media/v4l2-common.h>
static unsigned int i2c_debug;
module_param(i2c_debug, int, 0644);
MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
static unsigned int i2c_scan;
module_param(i2c_scan, int, 0444);
MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time");
#define dprintk(level, fmt, arg...)\
do { if (i2c_debug >= level)\
printk(KERN_DEBUG "%s/0: " fmt, dev->name, ## arg);\
} while (0)
#define I2C_WAIT_DELAY 32
#define I2C_WAIT_RETRY 64
#define I2C_EXTEND (1 << 3)
#define I2C_NOSTOP (1 << 4)
static inline int i2c_slave_did_ack(struct i2c_adapter *i2c_adap)
{
struct cx23885_i2c *bus = i2c_adap->algo_data;
struct cx23885_dev *dev = bus->dev;
return cx_read(bus->reg_stat) & 0x01;
}
static inline int i2c_is_busy(struct i2c_adapter *i2c_adap)
{
struct cx23885_i2c *bus = i2c_adap->algo_data;
struct cx23885_dev *dev = bus->dev;
return cx_read(bus->reg_stat) & 0x02 ? 1 : 0;
}
static int i2c_wait_done(struct i2c_adapter *i2c_adap)
{
int count;
for (count = 0; count < I2C_WAIT_RETRY; count++) {
if (!i2c_is_busy(i2c_adap))
break;
udelay(I2C_WAIT_DELAY);
}
if (I2C_WAIT_RETRY == count)
return 0;
return 1;
}
static int i2c_sendbytes(struct i2c_adapter *i2c_adap,
const struct i2c_msg *msg, int joined_rlen)
{
struct cx23885_i2c *bus = i2c_adap->algo_data;
struct cx23885_dev *dev = bus->dev;
u32 wdata, addr, ctrl;
int retval, cnt;
if (joined_rlen)
dprintk(1, "%s(msg->wlen=%d, nextmsg->rlen=%d)\n", __func__,
msg->len, joined_rlen);
else
dprintk(1, "%s(msg->len=%d)\n", __func__, msg->len);
/* Deal with i2c probe functions with zero payload */
if (msg->len == 0) {
cx_write(bus->reg_addr, msg->addr << 25);
cx_write(bus->reg_ctrl, bus->i2c_period | (1 << 2));
if (!i2c_wait_done(i2c_adap))
return -EIO;
if (!i2c_slave_did_ack(i2c_adap))
return -ENXIO;
dprintk(1, "%s() returns 0\n", __func__);
return 0;
}
/* dev, reg + first byte */
addr = (msg->addr << 25) | msg->buf[0];
wdata = msg->buf[0];
ctrl = bus->i2c_period | (1 << 12) | (1 << 2);
if (msg->len > 1)
ctrl |= I2C_NOSTOP | I2C_EXTEND;
else if (joined_rlen)
ctrl |= I2C_NOSTOP;
cx_write(bus->reg_addr, addr);
cx_write(bus->reg_wdata, wdata);
cx_write(bus->reg_ctrl, ctrl);
if (!i2c_wait_done(i2c_adap))
goto eio;
if (i2c_debug) {
printk(" <W %02x %02x", msg->addr << 1, msg->buf[0]);
if (!(ctrl & I2C_NOSTOP))
printk(" >\n");
}
for (cnt = 1; cnt < msg->len; cnt++) {
/* following bytes */
wdata = msg->buf[cnt];
ctrl = bus->i2c_period | (1 << 12) | (1 << 2);
if (cnt < msg->len - 1)
ctrl |= I2C_NOSTOP | I2C_EXTEND;
else if (joined_rlen)
ctrl |= I2C_NOSTOP;
cx_write(bus->reg_addr, addr);
cx_write(bus->reg_wdata, wdata);
cx_write(bus->reg_ctrl, ctrl);
if (!i2c_wait_done(i2c_adap))
goto eio;
if (i2c_debug) {
dprintk(1, " %02x", msg->buf[cnt]);
if (!(ctrl & I2C_NOSTOP))
dprintk(1, " >\n");
}
}
return msg->len;
eio:
retval = -EIO;
if (i2c_debug)
printk(KERN_ERR " ERR: %d\n", retval);
return retval;
}
static int i2c_readbytes(struct i2c_adapter *i2c_adap,
const struct i2c_msg *msg, int joined)
{
struct cx23885_i2c *bus = i2c_adap->algo_data;
struct cx23885_dev *dev = bus->dev;
u32 ctrl, cnt;
int retval;
if (i2c_debug && !joined)
dprintk(1, "%s(msg->len=%d)\n", __func__, msg->len);
/* Deal with i2c probe functions with zero payload */
if (msg->len == 0) {
cx_write(bus->reg_addr, msg->addr << 25);
cx_write(bus->reg_ctrl, bus->i2c_period | (1 << 2) | 1);
if (!i2c_wait_done(i2c_adap))
return -EIO;
if (!i2c_slave_did_ack(i2c_adap))
return -ENXIO;
dprintk(1, "%s() returns 0\n", __func__);
return 0;
}
if (i2c_debug) {
if (joined)
dprintk(1, " R");
else
dprintk(1, " <R %02x", (msg->addr << 1) + 1);
}
for (cnt = 0; cnt < msg->len; cnt++) {
ctrl = bus->i2c_period | (1 << 12) | (1 << 2) | 1;
if (cnt < msg->len - 1)
ctrl |= I2C_NOSTOP | I2C_EXTEND;
cx_write(bus->reg_addr, msg->addr << 25);
cx_write(bus->reg_ctrl, ctrl);
if (!i2c_wait_done(i2c_adap))
goto eio;
msg->buf[cnt] = cx_read(bus->reg_rdata) & 0xff;
if (i2c_debug) {
dprintk(1, " %02x", msg->buf[cnt]);
if (!(ctrl & I2C_NOSTOP))
dprintk(1, " >\n");
}
}
return msg->len;
eio:
retval = -EIO;
if (i2c_debug)
printk(KERN_ERR " ERR: %d\n", retval);
return retval;
}
static int i2c_xfer(struct i2c_adapter *i2c_adap,
struct i2c_msg *msgs, int num)
{
struct cx23885_i2c *bus = i2c_adap->algo_data;
struct cx23885_dev *dev = bus->dev;
int i, retval = 0;
dprintk(1, "%s(num = %d)\n", __func__, num);
for (i = 0 ; i < num; i++) {
dprintk(1, "%s(num = %d) addr = 0x%02x len = 0x%x\n",
__func__, num, msgs[i].addr, msgs[i].len);
if (msgs[i].flags & I2C_M_RD) {
/* read */
retval = i2c_readbytes(i2c_adap, &msgs[i], 0);
} else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&
msgs[i].addr == msgs[i + 1].addr) {
/* write then read from same address */
retval = i2c_sendbytes(i2c_adap, &msgs[i],
msgs[i + 1].len);
if (retval < 0)
goto err;
i++;
retval = i2c_readbytes(i2c_adap, &msgs[i], 1);
} else {
/* write */
retval = i2c_sendbytes(i2c_adap, &msgs[i], 0);
}
if (retval < 0)
goto err;
}
return num;
err:
return retval;
}
static u32 cx23885_functionality(struct i2c_adapter *adap)
{
return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
}
static struct i2c_algorithm cx23885_i2c_algo_template = {
.master_xfer = i2c_xfer,
.functionality = cx23885_functionality,
};
/* ----------------------------------------------------------------------- */
static struct i2c_adapter cx23885_i2c_adap_template = {
.name = "cx23885",
.owner = THIS_MODULE,
.algo = &cx23885_i2c_algo_template,
};
static struct i2c_client cx23885_i2c_client_template = {
.name = "cx23885 internal",
};
static char *i2c_devs[128] = {
[0x10 >> 1] = "tda10048",
[0x12 >> 1] = "dib7000pc",
[0x1c >> 1] = "lgdt3303",
[0x86 >> 1] = "tda9887",
[0x32 >> 1] = "cx24227",
[0x88 >> 1] = "cx25837",
[0x84 >> 1] = "tda8295",
[0x98 >> 1] = "flatiron",
[0xa0 >> 1] = "eeprom",
[0xc0 >> 1] = "tuner/mt2131/tda8275",
[0xc2 >> 1] = "tuner/mt2131/tda8275/xc5000/xc3028",
[0xc8 >> 1] = "tuner/xc3028L",
};
static void do_i2c_scan(char *name, struct i2c_client *c)
{
unsigned char buf;
int i, rc;
for (i = 0; i < 128; i++) {
c->addr = i;
rc = i2c_master_recv(c, &buf, 0);
if (rc < 0)
continue;
printk(KERN_INFO "%s: i2c scan: found device @ 0x%x [%s]\n",
name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
}
}
/* init + register i2c adapter */
int cx23885_i2c_register(struct cx23885_i2c *bus)
{
struct cx23885_dev *dev = bus->dev;
dprintk(1, "%s(bus = %d)\n", __func__, bus->nr);
bus->i2c_adap = cx23885_i2c_adap_template;
bus->i2c_client = cx23885_i2c_client_template;
bus->i2c_adap.dev.parent = &dev->pci->dev;
strlcpy(bus->i2c_adap.name, bus->dev->name,
sizeof(bus->i2c_adap.name));
bus->i2c_adap.algo_data = bus;
i2c_set_adapdata(&bus->i2c_adap, &dev->v4l2_dev);
i2c_add_adapter(&bus->i2c_adap);
bus->i2c_client.adapter = &bus->i2c_adap;
if (0 == bus->i2c_rc) {
dprintk(1, "%s: i2c bus %d registered\n", dev->name, bus->nr);
if (i2c_scan) {
printk(KERN_INFO "%s: scan bus %d:\n",
dev->name, bus->nr);
do_i2c_scan(dev->name, &bus->i2c_client);
}
} else
printk(KERN_WARNING "%s: i2c bus %d register FAILED\n",
dev->name, bus->nr);
/* Instantiate the IR receiver device, if present */
if (0 == bus->i2c_rc) {
struct i2c_board_info info;
const unsigned short addr_list[] = {
0x6b, I2C_CLIENT_END
};
memset(&info, 0, sizeof(struct i2c_board_info));
strlcpy(info.type, "ir_video", I2C_NAME_SIZE);
/* Use quick read command for probe, some IR chips don't
* support writes */
i2c_new_probed_device(&bus->i2c_adap, &info, addr_list,
i2c_probe_func_quick_read);
}
return bus->i2c_rc;
}
int cx23885_i2c_unregister(struct cx23885_i2c *bus)
{
i2c_del_adapter(&bus->i2c_adap);
return 0;
}
void cx23885_av_clk(struct cx23885_dev *dev, int enable)
{
/* write 0 to bus 2 addr 0x144 via i2x_xfer() */
char buffer[3];
struct i2c_msg msg;
dprintk(1, "%s(enabled = %d)\n", __func__, enable);
/* Register 0x144 */
buffer[0] = 0x01;
buffer[1] = 0x44;
if (enable == 1)
buffer[2] = 0x05;
else
buffer[2] = 0x00;
msg.addr = 0x44;
msg.flags = I2C_M_TEN;
msg.len = 3;
msg.buf = buffer;
i2c_xfer(&dev->i2c_bus[2].i2c_adap, &msg, 1);
}
/* ----------------------------------------------------------------------- */
/*
* Local variables:
* c-basic-offset: 8
* End:
*/