diff options
Diffstat (limited to 'drivers/media/tuners/si2157.c')
| -rw-r--r-- | drivers/media/tuners/si2157.c | 40 |
1 files changed, 39 insertions, 1 deletions
diff --git a/drivers/media/tuners/si2157.c b/drivers/media/tuners/si2157.c index 94db66107b98..6b452565dedb 100644 --- a/drivers/media/tuners/si2157.c +++ b/drivers/media/tuners/si2157.c @@ -726,6 +726,42 @@ static int si2157_get_if_frequency(struct dvb_frontend *fe, u32 *frequency) return 0; } +static int si2157_get_rf_strength(struct dvb_frontend *fe, u16 *rssi) +{ + struct i2c_client *client = fe->tuner_priv; + struct dtv_frontend_properties *c = &fe->dtv_property_cache; + struct si2157_cmd cmd; + int ret; + int strength; + + dev_dbg(&client->dev, "\n"); + + memcpy(cmd.args, "\x42\x00", 2); + cmd.wlen = 2; + cmd.rlen = 12; + ret = si2157_cmd_execute(client, &cmd); + if (ret) + goto err; + + c->strength.stat[0].scale = FE_SCALE_DECIBEL; + c->strength.stat[0].svalue = (s8)cmd.args[3] * 1000; + + /* normalize values based on Silicon Labs reference + * add 100, then anything > 80 is 100% signal + */ + strength = (s8)cmd.args[3] + 100; + strength = clamp_val(strength, 0, 80); + *rssi = (u16)(strength * 0xffff / 80); + + dev_dbg(&client->dev, "strength=%d rssi=%u\n", + (s8)cmd.args[3], *rssi); + + return 0; +err: + dev_dbg(&client->dev, "failed=%d\n", ret); + return ret; +} + static const struct dvb_tuner_ops si2157_ops = { .info = { .name = "Silicon Labs Si2141/Si2146/2147/2148/2157/2158", @@ -739,7 +775,9 @@ static const struct dvb_tuner_ops si2157_ops = { .set_analog_params = si2157_set_analog_params, .get_frequency = si2157_get_frequency, .get_bandwidth = si2157_get_bandwidth, - .get_if_frequency = si2157_get_if_frequency, + .get_if_frequency = si2157_get_if_frequency, + + .get_rf_strength = si2157_get_rf_strength, }; static void si2157_stat_work(struct work_struct *work) |