/*
* This file is part of linux driver the digital TV devices equipped with B2C2 FlexcopII(b)/III
*
* flexcop-i2c.c - flexcop internal 2Wire bus (I2C) and dvb i2c initialization
*
* see flexcop.c for copyright information.
*/
#include "flexcop.h"
#define FC_MAX_I2C_RETRIES 100000
static int flexcop_i2c_operation(struct flexcop_device *fc, flexcop_ibi_value *r100)
{
int i;
flexcop_ibi_value r;
r100->tw_sm_c_100.working_start = 1;
deb_i2c("r100 before: %08x\n",r100->raw);
fc->write_ibi_reg(fc, tw_sm_c_100, ibi_zero);
fc->write_ibi_reg(fc, tw_sm_c_100, *r100); /* initiating i2c operation */
for (i = 0; i < FC_MAX_I2C_RETRIES; i++) {
r = fc->read_ibi_reg(fc, tw_sm_c_100);
if (!r.tw_sm_c_100.no_base_addr_ack_error) {
if (r.tw_sm_c_100.st_done) { /* && !r.tw_sm_c_100.working_start */
*r100 = r;
deb_i2c("i2c success\n");
return 0;
}
} else {
deb_i2c("suffering from an i2c ack_error\n");
return -EREMOTEIO;
}
}
deb_i2c("tried %d times i2c operation, never finished or too many ack errors.\n",i);
return -EREMOTEIO;
}
static int flexcop_i2c_read4(struct flexcop_device *fc, flexcop_ibi_value r100, u8 *buf)
{
flexcop_ibi_value r104;
int len = r100.tw_sm_c_100.total_bytes, /* remember total_bytes is buflen-1 */
ret;
if ((ret = flexcop_i2c_operation(fc,&r100)) != 0) {
/* The Cablestar needs a different kind of i2c-transfer (does not
* support "Repeat Start"):
* wait for the ACK failure,
* and do a subsequent read with the Bit 30 enabled
*/
r100.tw_sm_c_100.no_base_addr_ack_error = 1;
if ((ret = flexcop_i2c_operation(fc,&r100)) != 0) {
deb_i2c("no_base_addr read failed. %d\n",ret);
return ret;
}
}
buf[0] = r100.tw_sm_c_100.data1_reg;
if (len > 0) {
r104 = fc->read_ibi_reg(fc,tw_sm_c_104);
deb_i2c("read: r100: %08x, r104: %08x\n",r100.raw,r104.raw);
/* there is at least one more byte, otherwise we wouldn't be here */
buf[1] = r104.tw_sm_c_104.data2_reg;
if (len > 1) buf[2] = r104.tw_sm_c_104.data3_reg;
if (len > 2) buf[3] = r104.tw_sm_c_104.data4_reg;
}
return 0;
}
static int flexcop_i2c_write4(struct flexcop_device *fc, flexcop_ibi_value r100, u8 *buf)
{
flexcop_ibi_value r104;
int len = r100.tw_sm_c_100.total_bytes; /* remember total_bytes is buflen-1 */
r104.raw = 0;
/* there is at least one byte, otherwise we wouldn't be here */
r100.tw_sm_c_100.data1_reg = buf[0];
r104.tw_sm_c_104.data2_reg = len > 0 ? buf[1] : 0;
r104.tw_sm_c_104.data3_reg = len > 1 ? buf[2] : 0;
r104.tw_sm_c_104.data4_reg = len > 2 ? buf[3] : 0;
deb_i2c("write: r100: %08x, r104: %08x\n",r100.raw,r104.raw);
/* write the additional i2c data before doing the actual i2c operation */
fc->write_ibi_reg(fc,tw_sm_c_104,r104);
return flexcop_i2c_operation(fc,&r100);
}
int flexcop_i2c_request(struct flexcop_device *fc, flexcop_access_op_t op,
flexcop_i2c_port_t port, u8 chipaddr, u8 addr, u8 *buf, u16 len)
{
int ret;
u16 bytes_to_transfer;
flexcop_ibi_value r100;
deb_i2c("op = %d\n",op);
r100.raw = 0;
r100.tw_sm_c_100.chipaddr = chipaddr;
r100.tw_sm_c_100.twoWS_rw = op;
r100.tw_sm_c_100.twoWS_port_reg = port;
while (len != 0) {
bytes_to_transfer = len > 4 ? 4 : len;
r100.tw_sm_c_100.total_bytes = bytes_to_transfer - 1;
r100.tw_sm_c_100.baseaddr = addr;
if (op == FC_READ)
ret = flexcop_i2c_read4(fc, r100, buf);
else
ret = flexcop_i2c_write4(fc,r100, buf);
if (ret < 0)
return ret;
buf += bytes_to_transfer;
addr += bytes_to_transfer;
len -= bytes_to_transfer;
};
return 0;
}
/* exported for PCI i2c */
EXPORT_SYMBOL(flexcop_i2c_request);
/* master xfer callback for demodulator */
static int flexcop_master_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num)
{
struct flexcop_device *fc = i2c_get_adapdata(i2c_adap);
int i, ret = 0;
if (down_interruptible(&fc->i2c_sem))
return -ERESTARTSYS;
/* reading */
if (num == 2 &&
msgs[0].flags == 0 &&
msgs[1].flags == I2C_M_RD &&
msgs[0].buf != NULL &&
msgs[1].buf != NULL) {
ret = fc->i2c_request(fc, FC_READ, FC_I2C_PORT_DEMOD, msgs[0].addr, msgs[0].buf[0], msgs[1].buf, msgs[1].len);
} else for (i = 0; i < num; i++) { /* writing command */
if (msgs[i].flags != 0 || msgs[i].buf == NULL || msgs[i].len < 2) {
ret = -EINVAL;
break;
}
ret = fc->i2c_request(fc, FC_WRITE, FC_I2C_PORT_DEMOD, msgs[i].addr, msgs[i].buf[0], &msgs[i].buf[1], msgs[i].len - 1);
}
if (ret < 0)
err("i2c master_xfer failed");
else
ret = num;
up(&fc->i2c_sem);
return ret;
}
static u32 flexcop_i2c_func(struct i2c_adapter *adapter)
{
return I2C_FUNC_I2C;
}
static struct i2c_algorithm flexcop_algo = {
.name = "FlexCop I2C algorithm",
.id = I2C_ALGO_BIT,
.master_xfer = flexcop_master_xfer,
.functionality = flexcop_i2c_func,
};
int flexcop_i2c_init(struct flexcop_device *fc)
{
int ret;
sema_init(&fc->i2c_sem,1);
memset(&fc->i2c_adap, 0, sizeof(struct i2c_adapter));
strncpy(fc->i2c_adap.name, "B2C2 FlexCop device",I2C_NAME_SIZE);
i2c_set_adapdata(&fc->i2c_adap,fc);
fc->i2c_adap.class = I2C_CLASS_TV_DIGITAL;
fc->i2c_adap.algo = &flexcop_algo;
fc->i2c_adap.algo_data = NULL;
fc->i2c_adap.id = I2C_ALGO_BIT;
if ((ret = i2c_add_adapter(&fc->i2c_adap)) < 0)
return ret;
fc->init_state |= FC_STATE_I2C_INIT;
return 0;
}
void flexcop_i2c_exit(struct flexcop_device *fc)
{
if (fc->init_state & FC_STATE_I2C_INIT)
i2c_del_adapter(&fc->i2c_adap);
fc->init_state &= ~FC_STATE_I2C_INIT;
}
