diff options
Diffstat (limited to 'drivers/media/dvb/pt1/va1j5jf8007t.c')
| -rw-r--r-- | drivers/media/dvb/pt1/va1j5jf8007t.c | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/drivers/media/dvb/pt1/va1j5jf8007t.c b/drivers/media/dvb/pt1/va1j5jf8007t.c index 71117f4ca7e6..fe897343f4f8 100644 --- a/drivers/media/dvb/pt1/va1j5jf8007t.c +++ b/drivers/media/dvb/pt1/va1j5jf8007t.c @@ -46,6 +46,52 @@ struct va1j5jf8007t_state { enum va1j5jf8007t_tune_state tune_state; }; +static int va1j5jf8007t_read_snr(struct dvb_frontend *fe, u16 *snr) +{ + struct va1j5jf8007t_state *state; + u8 addr; + int i; + u8 write_buf[1], read_buf[1]; + struct i2c_msg msgs[2]; + s32 word, x, y; + + state = fe->demodulator_priv; + addr = state->config->demod_address; + + word = 0; + for (i = 0; i < 3; i++) { + write_buf[0] = 0x8b + i; + + msgs[0].addr = addr; + msgs[0].flags = 0; + msgs[0].len = sizeof(write_buf); + msgs[0].buf = write_buf; + + msgs[1].addr = addr; + msgs[1].flags = I2C_M_RD; + msgs[1].len = sizeof(read_buf); + msgs[1].buf = read_buf; + + if (i2c_transfer(state->adap, msgs, 2) != 2) + return -EREMOTEIO; + + word <<= 8; + word |= read_buf[0]; + } + + if (!word) + return -EIO; + + x = 10 * (intlog10(0x540000 * 100 / word) - (2 << 24)); + y = (24ll << 46) / 1000000; + y = ((s64)y * x >> 30) - (16ll << 40) / 10000; + y = ((s64)y * x >> 29) + (398ll << 35) / 10000; + y = ((s64)y * x >> 30) + (5491ll << 29) / 10000; + y = ((s64)y * x >> 30) + (30965ll << 23) / 10000; + *snr = y >> 15; + return 0; +} + static int va1j5jf8007t_get_frontend_algo(struct dvb_frontend *fe) { return DVBFE_ALGO_HW; @@ -393,6 +439,7 @@ static struct dvb_frontend_ops va1j5jf8007t_ops = { FE_CAN_GUARD_INTERVAL_AUTO | FE_CAN_HIERARCHY_AUTO, }, + .read_snr = va1j5jf8007t_read_snr, .get_frontend_algo = va1j5jf8007t_get_frontend_algo, .read_status = va1j5jf8007t_read_status, .tune = va1j5jf8007t_tune, |