static int
usbvision_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num)
{
struct i2c_msg *pmsg;
struct usb_usbvision *usbvision;
int i, ret;
unsigned char addr = 0;
usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
for (i = 0; i < num; i++) {
pmsg = &msgs[i];
ret = usb_find_address(i2c_adap, pmsg, i2c_adap->retries, &addr);
if (ret != 0) {
PDEBUG(DBG_I2C, "got NAK from device, message #%d", i);
return (ret < 0) ? ret : -EREMOTEIO;
}
if (pmsg->flags & I2C_M_RD) {
/* */
ret = (usbvision_i2c_read(usbvision, addr, pmsg->buf, pmsg->len));
if (ret < pmsg->len)
return (ret < 0) ? ret : -EREMOTEIO;
} else {
/* */
ret = (usbvision_i2c_write(usbvision, addr, pmsg->buf, pmsg->len));
if (ret < pmsg->len)
return (ret < 0) ? ret : -EREMOTEIO;
}
}
return num;
}
static inline int try_read_address(struct i2c_adapter *i2c_adap,
unsigned char addr, int retries)
{
struct usb_usbvision *usbvision;
int i, ret = -1;
char buf[4];
usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
for (i = 0; i <= retries; i++) {
ret = (usbvision_i2c_read(usbvision, addr, buf, 1));
if (ret == 1)
break; /* success! */
udelay(5);
if (i == retries) /* no success */
break;
udelay(10);
}
if (i) {
PDEBUG(DBG_I2C,"Needed %d retries for address %#2x", i, addr);
PDEBUG(DBG_I2C,"Maybe there's no device at this address");
}
return ret;
}