295 строки
6.1 KiB
C
295 строки
6.1 KiB
C
/*
|
|
* STK1160 driver
|
|
*
|
|
* Copyright (C) 2012 Ezequiel Garcia
|
|
* <elezegarcia--a.t--gmail.com>
|
|
*
|
|
* Based on Easycap driver by R.M. Thomas
|
|
* Copyright (C) 2010 R.M. Thomas
|
|
* <rmthomas--a.t--sciolus.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.
|
|
*
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/usb.h>
|
|
#include <linux/i2c.h>
|
|
|
|
#include "stk1160.h"
|
|
#include "stk1160-reg.h"
|
|
|
|
static unsigned int i2c_debug;
|
|
module_param(i2c_debug, int, 0644);
|
|
MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
|
|
|
|
#define dprintk_i2c(fmt, args...) \
|
|
do { \
|
|
if (i2c_debug) \
|
|
printk(KERN_DEBUG fmt, ##args); \
|
|
} while (0)
|
|
|
|
static int stk1160_i2c_busy_wait(struct stk1160 *dev, u8 wait_bit_mask)
|
|
{
|
|
unsigned long end;
|
|
u8 flag;
|
|
|
|
/* Wait until read/write finish bit is set */
|
|
end = jiffies + msecs_to_jiffies(STK1160_I2C_TIMEOUT);
|
|
while (time_is_after_jiffies(end)) {
|
|
|
|
stk1160_read_reg(dev, STK1160_SICTL+1, &flag);
|
|
/* read/write done? */
|
|
if (flag & wait_bit_mask)
|
|
goto done;
|
|
|
|
usleep_range(10 * USEC_PER_MSEC, 20 * USEC_PER_MSEC);
|
|
}
|
|
|
|
return -ETIMEDOUT;
|
|
|
|
done:
|
|
return 0;
|
|
}
|
|
|
|
static int stk1160_i2c_write_reg(struct stk1160 *dev, u8 addr,
|
|
u8 reg, u8 value)
|
|
{
|
|
int rc;
|
|
|
|
/* Set serial device address */
|
|
rc = stk1160_write_reg(dev, STK1160_SICTL_SDA, addr);
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
/* Set i2c device register sub-address */
|
|
rc = stk1160_write_reg(dev, STK1160_SBUSW_WA, reg);
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
/* Set i2c device register value */
|
|
rc = stk1160_write_reg(dev, STK1160_SBUSW_WD, value);
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
/* Start write now */
|
|
rc = stk1160_write_reg(dev, STK1160_SICTL, 0x01);
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
rc = stk1160_i2c_busy_wait(dev, 0x04);
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int stk1160_i2c_read_reg(struct stk1160 *dev, u8 addr,
|
|
u8 reg, u8 *value)
|
|
{
|
|
int rc;
|
|
|
|
/* Set serial device address */
|
|
rc = stk1160_write_reg(dev, STK1160_SICTL_SDA, addr);
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
/* Set i2c device register sub-address */
|
|
rc = stk1160_write_reg(dev, STK1160_SBUSR_RA, reg);
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
/* Start read now */
|
|
rc = stk1160_write_reg(dev, STK1160_SICTL, 0x20);
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
rc = stk1160_i2c_busy_wait(dev, 0x01);
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
rc = stk1160_read_reg(dev, STK1160_SBUSR_RD, value);
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* stk1160_i2c_check_for_device()
|
|
* check if there is a i2c_device at the supplied address
|
|
*/
|
|
static int stk1160_i2c_check_for_device(struct stk1160 *dev,
|
|
unsigned char addr)
|
|
{
|
|
int rc;
|
|
|
|
/* Set serial device address */
|
|
rc = stk1160_write_reg(dev, STK1160_SICTL_SDA, addr);
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
/* Set device sub-address, we'll chip version reg */
|
|
rc = stk1160_write_reg(dev, STK1160_SBUSR_RA, 0x00);
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
/* Start read now */
|
|
rc = stk1160_write_reg(dev, STK1160_SICTL, 0x20);
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
rc = stk1160_i2c_busy_wait(dev, 0x01);
|
|
if (rc < 0)
|
|
return -ENODEV;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* stk1160_i2c_xfer()
|
|
* the main i2c transfer function
|
|
*/
|
|
static int stk1160_i2c_xfer(struct i2c_adapter *i2c_adap,
|
|
struct i2c_msg msgs[], int num)
|
|
{
|
|
struct stk1160 *dev = i2c_adap->algo_data;
|
|
int addr, rc, i;
|
|
|
|
for (i = 0; i < num; i++) {
|
|
addr = msgs[i].addr << 1;
|
|
dprintk_i2c("%s: addr=%x", __func__, addr);
|
|
|
|
if (!msgs[i].len) {
|
|
/* no len: check only for device presence */
|
|
rc = stk1160_i2c_check_for_device(dev, addr);
|
|
if (rc < 0) {
|
|
dprintk_i2c(" no device\n");
|
|
return rc;
|
|
}
|
|
|
|
} else if (msgs[i].flags & I2C_M_RD) {
|
|
/* read request without preceding register selection */
|
|
dprintk_i2c(" subaddr not selected");
|
|
rc = -EOPNOTSUPP;
|
|
goto err;
|
|
|
|
} else if (i + 1 < num && msgs[i].len <= 2 &&
|
|
(msgs[i + 1].flags & I2C_M_RD) &&
|
|
msgs[i].addr == msgs[i + 1].addr) {
|
|
|
|
if (msgs[i].len != 1 || msgs[i + 1].len != 1) {
|
|
dprintk_i2c(" len not supported");
|
|
rc = -EOPNOTSUPP;
|
|
goto err;
|
|
}
|
|
|
|
dprintk_i2c(" subaddr=%x", msgs[i].buf[0]);
|
|
|
|
rc = stk1160_i2c_read_reg(dev, addr, msgs[i].buf[0],
|
|
msgs[i + 1].buf);
|
|
|
|
dprintk_i2c(" read=%x", *msgs[i + 1].buf);
|
|
|
|
/* consumed two msgs, so we skip one of them */
|
|
i++;
|
|
|
|
} else {
|
|
if (msgs[i].len != 2) {
|
|
dprintk_i2c(" len not supported");
|
|
rc = -EOPNOTSUPP;
|
|
goto err;
|
|
}
|
|
|
|
dprintk_i2c(" subaddr=%x write=%x",
|
|
msgs[i].buf[0], msgs[i].buf[1]);
|
|
|
|
rc = stk1160_i2c_write_reg(dev, addr, msgs[i].buf[0],
|
|
msgs[i].buf[1]);
|
|
}
|
|
|
|
if (rc < 0)
|
|
goto err;
|
|
dprintk_i2c(" OK\n");
|
|
}
|
|
|
|
return num;
|
|
err:
|
|
dprintk_i2c(" ERROR: %d\n", rc);
|
|
return num;
|
|
}
|
|
|
|
/*
|
|
* functionality(), what da heck is this?
|
|
*/
|
|
static u32 functionality(struct i2c_adapter *adap)
|
|
{
|
|
return I2C_FUNC_SMBUS_EMUL;
|
|
}
|
|
|
|
static struct i2c_algorithm algo = {
|
|
.master_xfer = stk1160_i2c_xfer,
|
|
.functionality = functionality,
|
|
};
|
|
|
|
static struct i2c_adapter adap_template = {
|
|
.owner = THIS_MODULE,
|
|
.name = "stk1160",
|
|
.algo = &algo,
|
|
};
|
|
|
|
static struct i2c_client client_template = {
|
|
.name = "stk1160 internal",
|
|
};
|
|
|
|
/*
|
|
* stk1160_i2c_register()
|
|
* register i2c bus
|
|
*/
|
|
int stk1160_i2c_register(struct stk1160 *dev)
|
|
{
|
|
int rc;
|
|
|
|
dev->i2c_adap = adap_template;
|
|
dev->i2c_adap.dev.parent = dev->dev;
|
|
strcpy(dev->i2c_adap.name, "stk1160");
|
|
dev->i2c_adap.algo_data = dev;
|
|
|
|
i2c_set_adapdata(&dev->i2c_adap, &dev->v4l2_dev);
|
|
|
|
rc = i2c_add_adapter(&dev->i2c_adap);
|
|
if (rc < 0) {
|
|
stk1160_err("cannot add i2c adapter (%d)\n", rc);
|
|
return rc;
|
|
}
|
|
|
|
dev->i2c_client = client_template;
|
|
dev->i2c_client.adapter = &dev->i2c_adap;
|
|
|
|
/* Set i2c clock divider device address */
|
|
stk1160_write_reg(dev, STK1160_SICTL_CD, 0x0f);
|
|
|
|
/* ??? */
|
|
stk1160_write_reg(dev, STK1160_ASIC + 3, 0x00);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* stk1160_i2c_unregister()
|
|
* unregister i2c_bus
|
|
*/
|
|
int stk1160_i2c_unregister(struct stk1160 *dev)
|
|
{
|
|
i2c_del_adapter(&dev->i2c_adap);
|
|
return 0;
|
|
}
|