diff options
Diffstat (limited to 'drivers/media/dvb-frontends/drx39xyj')
| -rw-r--r-- | drivers/media/dvb-frontends/drx39xyj/drxj.c | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/drivers/media/dvb-frontends/drx39xyj/drxj.c b/drivers/media/dvb-frontends/drx39xyj/drxj.c index 7022a69f56bd..ca807b1fc67c 100644 --- a/drivers/media/dvb-frontends/drx39xyj/drxj.c +++ b/drivers/media/dvb-frontends/drx39xyj/drxj.c @@ -9352,6 +9352,83 @@ rw_error: /*============================================================================*/ /** + * \fn int get_sig_strength() + * \brief Retrieve signal strength for VSB and QAM. + * \param demod Pointer to demod instance + * \param u16-t Pointer to signal strength data; range 0, .. , 100. + * \return int. + * \retval 0 sig_strength contains valid data. + * \retval -EINVAL sig_strength is NULL. + * \retval -EIO Erroneous data, sig_strength contains invalid data. + */ +#define DRXJ_AGC_TOP 0x2800 +#define DRXJ_AGC_SNS 0x1600 +#define DRXJ_RFAGC_MAX 0x3fff +#define DRXJ_RFAGC_MIN 0x800 + +static int get_sig_strength(struct drx_demod_instance *demod, u16 *sig_strength) +{ + struct i2c_device_addr *dev_addr = demod->my_i2c_dev_addr; + int rc; + u16 rf_gain = 0; + u16 if_gain = 0; + u16 if_agc_sns = 0; + u16 if_agc_top = 0; + u16 rf_agc_max = 0; + u16 rf_agc_min = 0; + + rc = drxj_dap_read_reg16(dev_addr, IQM_AF_AGC_IF__A, &if_gain, 0); + if (rc != 0) { + pr_err("error %d\n", rc); + goto rw_error; + } + if_gain &= IQM_AF_AGC_IF__M; + rc = drxj_dap_read_reg16(dev_addr, IQM_AF_AGC_RF__A, &rf_gain, 0); + if (rc != 0) { + pr_err("error %d\n", rc); + goto rw_error; + } + rf_gain &= IQM_AF_AGC_RF__M; + + if_agc_sns = DRXJ_AGC_SNS; + if_agc_top = DRXJ_AGC_TOP; + rf_agc_max = DRXJ_RFAGC_MAX; + rf_agc_min = DRXJ_RFAGC_MIN; + + if (if_gain > if_agc_top) { + if (rf_gain > rf_agc_max) + *sig_strength = 100; + else if (rf_gain > rf_agc_min) { + if (rf_agc_max == rf_agc_min) { + pr_err("error: rf_agc_max == rf_agc_min\n"); + return -EIO; + } + *sig_strength = + 75 + 25 * (rf_gain - rf_agc_min) / (rf_agc_max - + rf_agc_min); + } else + *sig_strength = 75; + } else if (if_gain > if_agc_sns) { + if (if_agc_top == if_agc_sns) { + pr_err("error: if_agc_top == if_agc_sns\n"); + return -EIO; + } + *sig_strength = + 20 + 55 * (if_gain - if_agc_sns) / (if_agc_top - if_agc_sns); + } else { + if (!if_agc_sns) { + pr_err("error: if_agc_sns is zero!\n"); + return -EIO; + } + *sig_strength = (20 * if_gain / if_agc_sns); + } + + return 0; + rw_error: + return -EIO; +} + +/** * \fn int ctrl_get_qam_sig_quality() * \brief Retreive QAM signal quality from device. * \param devmod Pointer to demodulator instance. |