swh:1:snp:173f8deb0c56c557784b4fd217e7608ac6197844
Tip revision: 6221f222c0ebf1acdf7abcf927178f40e1a65e2a authored by Linus Torvalds on 06 April 2011, 01:30:43 UTC
Linux 2.6.39-rc2
Linux 2.6.39-rc2
Tip revision: 6221f22
flexcop-i2c.c
/*
* Linux driver for 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) {
*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_i2c_adapter *i2c,
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;
/* work-around to have CableStar2 and SkyStar2 rev 2.7 work
* correctly:
*
* the ITD1000 is behind an i2c-gate which closes automatically
* after an i2c-transaction the STV0297 needs 2 consecutive reads
* one with no_base_addr = 0 and one with 1
*
* those two work-arounds are conflictin: we check for the card
* type, it is set when probing the ITD1000 */
if (i2c->fc->dev_type == FC_SKY_REV27)
r100.tw_sm_c_100.no_base_addr_ack_error = i2c->no_base_addr;
ret = flexcop_i2c_operation(i2c->fc, &r100);
if (ret != 0) {
deb_i2c("Retrying operation\n");
r100.tw_sm_c_100.no_base_addr_ack_error = i2c->no_base_addr;
ret = flexcop_i2c_operation(i2c->fc, &r100);
}
if (ret != 0) {
deb_i2c("read failed. %d\n", ret);
return ret;
}
buf[0] = r100.tw_sm_c_100.data1_reg;
if (len > 0) {
r104 = i2c->fc->read_ibi_reg(i2c->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_i2c_adapter *i2c,
flexcop_access_op_t op, u8 chipaddr, u8 addr, u8 *buf, u16 len)
{
int ret;
#ifdef DUMP_I2C_MESSAGES
int i;
#endif
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 = i2c->port;
#ifdef DUMP_I2C_MESSAGES
printk(KERN_DEBUG "%d ", i2c->port);
if (op == FC_READ)
printk("rd(");
else
printk("wr(");
printk("%02x): %02x ", chipaddr, addr);
#endif
/* in that case addr is the only value ->
* we write it twice as baseaddr and val0
* BBTI is doing it like that for ISL6421 at least */
if (i2c->no_base_addr && len == 0 && op == FC_WRITE) {
buf = &addr;
len = 1;
}
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(i2c, r100, buf);
else
ret = flexcop_i2c_write4(i2c->fc, r100, buf);
#ifdef DUMP_I2C_MESSAGES
for (i = 0; i < bytes_to_transfer; i++)
printk("%02x ", buf[i]);
#endif
if (ret < 0)
return ret;
buf += bytes_to_transfer;
addr += bytes_to_transfer;
len -= bytes_to_transfer;
}
#ifdef DUMP_I2C_MESSAGES
printk("\n");
#endif
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_i2c_adapter *i2c = i2c_get_adapdata(i2c_adap);
int i, ret = 0;
/* Some drivers use 1 byte or 0 byte reads as probes, which this
* driver doesn't support. These probes will always fail, so this
* hack makes them always succeed. If one knew how, it would of
* course be better to actually do the read. */
if (num == 1 && msgs[0].flags == I2C_M_RD && msgs[0].len <= 1)
return 1;
if (mutex_lock_interruptible(&i2c->fc->i2c_mutex))
return -ERESTARTSYS;
for (i = 0; i < num; i++) {
/* reading */
if (i+1 < num && (msgs[i+1].flags == I2C_M_RD)) {
ret = i2c->fc->i2c_request(i2c, FC_READ, msgs[i].addr,
msgs[i].buf[0], msgs[i+1].buf,
msgs[i+1].len);
i++; /* skip the following message */
} else /* writing */
ret = i2c->fc->i2c_request(i2c, FC_WRITE, msgs[i].addr,
msgs[i].buf[0], &msgs[i].buf[1],
msgs[i].len - 1);
if (ret < 0) {
deb_i2c("i2c master_xfer failed");
break;
}
}
mutex_unlock(&i2c->fc->i2c_mutex);
if (ret == 0)
ret = num;
return ret;
}
static u32 flexcop_i2c_func(struct i2c_adapter *adapter)
{
return I2C_FUNC_I2C;
}
static struct i2c_algorithm flexcop_algo = {
.master_xfer = flexcop_master_xfer,
.functionality = flexcop_i2c_func,
};
int flexcop_i2c_init(struct flexcop_device *fc)
{
int ret;
mutex_init(&fc->i2c_mutex);
fc->fc_i2c_adap[0].fc = fc;
fc->fc_i2c_adap[1].fc = fc;
fc->fc_i2c_adap[2].fc = fc;
fc->fc_i2c_adap[0].port = FC_I2C_PORT_DEMOD;
fc->fc_i2c_adap[1].port = FC_I2C_PORT_EEPROM;
fc->fc_i2c_adap[2].port = FC_I2C_PORT_TUNER;
strlcpy(fc->fc_i2c_adap[0].i2c_adap.name, "B2C2 FlexCop I2C to demod",
sizeof(fc->fc_i2c_adap[0].i2c_adap.name));
strlcpy(fc->fc_i2c_adap[1].i2c_adap.name, "B2C2 FlexCop I2C to eeprom",
sizeof(fc->fc_i2c_adap[1].i2c_adap.name));
strlcpy(fc->fc_i2c_adap[2].i2c_adap.name, "B2C2 FlexCop I2C to tuner",
sizeof(fc->fc_i2c_adap[2].i2c_adap.name));
i2c_set_adapdata(&fc->fc_i2c_adap[0].i2c_adap, &fc->fc_i2c_adap[0]);
i2c_set_adapdata(&fc->fc_i2c_adap[1].i2c_adap, &fc->fc_i2c_adap[1]);
i2c_set_adapdata(&fc->fc_i2c_adap[2].i2c_adap, &fc->fc_i2c_adap[2]);
fc->fc_i2c_adap[0].i2c_adap.algo =
fc->fc_i2c_adap[1].i2c_adap.algo =
fc->fc_i2c_adap[2].i2c_adap.algo = &flexcop_algo;
fc->fc_i2c_adap[0].i2c_adap.algo_data =
fc->fc_i2c_adap[1].i2c_adap.algo_data =
fc->fc_i2c_adap[2].i2c_adap.algo_data = NULL;
fc->fc_i2c_adap[0].i2c_adap.dev.parent =
fc->fc_i2c_adap[1].i2c_adap.dev.parent =
fc->fc_i2c_adap[2].i2c_adap.dev.parent = fc->dev;
ret = i2c_add_adapter(&fc->fc_i2c_adap[0].i2c_adap);
if (ret < 0)
return ret;
ret = i2c_add_adapter(&fc->fc_i2c_adap[1].i2c_adap);
if (ret < 0)
goto adap_1_failed;
ret = i2c_add_adapter(&fc->fc_i2c_adap[2].i2c_adap);
if (ret < 0)
goto adap_2_failed;
fc->init_state |= FC_STATE_I2C_INIT;
return 0;
adap_2_failed:
i2c_del_adapter(&fc->fc_i2c_adap[1].i2c_adap);
adap_1_failed:
i2c_del_adapter(&fc->fc_i2c_adap[0].i2c_adap);
return ret;
}
void flexcop_i2c_exit(struct flexcop_device *fc)
{
if (fc->init_state & FC_STATE_I2C_INIT) {
i2c_del_adapter(&fc->fc_i2c_adap[2].i2c_adap);
i2c_del_adapter(&fc->fc_i2c_adap[1].i2c_adap);
i2c_del_adapter(&fc->fc_i2c_adap[0].i2c_adap);
}
fc->init_state &= ~FC_STATE_I2C_INIT;
}