[media] fc0012 ver. 0.6: introduction of get_rf_strength function

Changes compared to version 0.5 of driver (sent 6 May):
- Initial implementation of get_rf_strength function.

Signed-off-by: Hans-Frieder Vogt <hfvogt@gmx.net>
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 71 insertions, 1 deletions

diff --git a/drivers/media/common/tuners/fc0012.c b/drivers/media/common/tuners/fc0012.c
index cd58f90d7d13..308135abd54c 100644
--- a/drivers/media/common/tuners/fc0012.c
+++ b/drivers/media/common/tuners/fc0012.c
@@ -343,6 +343,74 @@ static int fc0012_get_bandwidth(struct dvb_frontend *fe, u32 *bandwidth)
         return 0;
 }
 
+#define INPUT_ADC_LEVEL -8
+
+static int fc0012_get_rf_strength(struct dvb_frontend *fe, u16 *strength)
+{
+        struct fc0012_priv *priv = fe->tuner_priv;
+        int ret;
+        unsigned char tmp;
+        int int_temp, lna_gain, int_lna, tot_agc_gain, power;
+        const int fc0012_lna_gain_table[] = {
+                /* low gain */
+                -63, -58, -99, -73,
+                -63, -65, -54, -60,
+                /* middle gain */
+                 71,  70,  68,  67,
+                 65,  63,  61,  58,
+                /* high gain */
+                197, 191, 188, 186,
+                184, 182, 181, 179,
+        };
+
+        if (fe->ops.i2c_gate_ctrl)
+                fe->ops.i2c_gate_ctrl(fe, 1); /* open I2C-gate */
+
+        ret = fc0012_writereg(priv, 0x12, 0x00);
+        if (ret)
+                goto err;
+
+        ret = fc0012_readreg(priv, 0x12, &tmp);
+        if (ret)
+                goto err;
+        int_temp = tmp;
+
+        ret = fc0012_readreg(priv, 0x13, &tmp);
+        if (ret)
+                goto err;
+        lna_gain = tmp & 0x1f;
+
+        if (fe->ops.i2c_gate_ctrl)
+                fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */
+
+        if (lna_gain < ARRAY_SIZE(fc0012_lna_gain_table)) {
+                int_lna = fc0012_lna_gain_table[lna_gain];
+                tot_agc_gain = (abs((int_temp >> 5) - 7) - 2 +
+                                (int_temp & 0x1f)) * 2;
+                power = INPUT_ADC_LEVEL - tot_agc_gain - int_lna / 10;
+
+                if (power >= 45)
+                        *strength = 255;        /* 100% */
+                else if (power < -95)
+                        *strength = 0;
+                else
+                        *strength = (power + 95) * 255 / 140;
+
+                *strength |= *strength << 8;
+        } else {
+                ret = -1;
+        }
+
+        goto exit;
+
+err:
+        if (fe->ops.i2c_gate_ctrl)
+                fe->ops.i2c_gate_ctrl(fe, 0); /* close I2C-gate */
+exit:
+        if (ret)
+                warn("%s: failed: %d", __func__, ret);
+        return ret;
+}
 
 static const struct dvb_tuner_ops fc0012_tuner_ops = {
         .info = {
@@ -363,6 +431,8 @@ static const struct dvb_tuner_ops fc0012_tuner_ops = {
         .get_frequency  = fc0012_get_frequency,
         .get_if_frequency = fc0012_get_if_frequency,
         .get_bandwidth  = fc0012_get_bandwidth,
+
+        .get_rf_strength = fc0012_get_rf_strength,
 };
 
 struct dvb_frontend *fc0012_attach(struct dvb_frontend *fe,
@@ -394,4 +464,4 @@ EXPORT_SYMBOL(fc0012_attach);
 MODULE_DESCRIPTION("Fitipower FC0012 silicon tuner driver");
 MODULE_AUTHOR("Hans-Frieder Vogt <hfvogt@gmx.net>");
 MODULE_LICENSE("GPL");
-MODULE_VERSION("0.5");
+MODULE_VERSION("0.6");