diff options
Diffstat (limited to 'drivers/media/dvb/b2c2/flexcop-i2c.c')
| -rw-r--r-- | drivers/media/dvb/b2c2/flexcop-i2c.c | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/drivers/media/dvb/b2c2/flexcop-i2c.c b/drivers/media/dvb/b2c2/flexcop-i2c.c new file mode 100644 index 000000000000..be4266d4ae91 --- /dev/null +++ b/drivers/media/dvb/b2c2/flexcop-i2c.c @@ -0,0 +1,210 @@ +/* + * 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; +} |