[media] dvb-core, tda18271c2dd: define get_if_frequency() callback

Tuners in general convert a high frequency carrier into an Intermediate
Frequency (IF).

Digital tuners like tda18271, xc3028, etc. generally allow changing the IF
frequency, although they generally have recommented settings for the IF.
Analog tuners, have a fixed IF frequency, that depends on the physical
characteristics of some analog components.

For digital tuners, it makes sense to have ways to configure IF,
via the tuner's configuration structure, like what's done inside the
tda18271-fe maps.

The demods need to know what IF is used by the tuner, as it will need
to convert internally from IF into baseband. Currently, the bridge driver
needs to fill a per-demod configuration struct for it, or pass it via
a dvb_attach parameter.

The tda18271 datasheet recommends to use different IF's for different
delivery system types and for different bandwidths.

The DRX-K demod also needs to know the IF frequency in order to work,
just like all other demods. However, as it accepts different delivery
systems (DVB-C and DVB-T), the IF may change if the standard and/or
bandwidth is changed.

So, the usual procedure of passing it via a config struct doesn't work.

One might try to code it as two separate IF frequencies, or even as a
table in function of the delivery system and the bandwidth, but this
will be messy.

So, it is better and simpler to just add a new callback for it and
require the tuners that can be used with MFE frontends like drx-k
to implement a new callback to return the used IF.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: Antti Palosaari <crope@iki.fi>

diff --git a/drivers/media/dvb/dvb-core/dvb_frontend.h b/drivers/media/dvb/dvb-core/dvb_frontend.h
index 5590eb6eb4082a8967e6821c3fff64d1332655c6..67bbfa728016f72ef600bd683d84ef422930362e 100644 (file)
--- a/drivers/media/dvb/dvb-core/dvb_frontend.h
+++ b/drivers/media/dvb/dvb-core/dvb_frontend.h
@@ -209,6 +209,7 @@ struct dvb_tuner_ops {
 
        int (*get_frequency)(struct dvb_frontend *fe, u32 *frequency);
        int (*get_bandwidth)(struct dvb_frontend *fe, u32 *bandwidth);
+       int (*get_if_frequency)(struct dvb_frontend *fe, u32 *frequency);
 
 #define TUNER_STATUS_LOCKED 1
 #define TUNER_STATUS_STEREO 2

diff --git a/drivers/media/dvb/frontends/drxk_hard.c b/drivers/media/dvb/frontends/drxk_hard.c
index 41b083820dae96ff726b1cca505ba7a8415bb85c..f6431ef827dc1f86e6b4748ae08c5edb141919ff 100644 (file)
--- a/drivers/media/dvb/frontends/drxk_hard.c
+++ b/drivers/media/dvb/frontends/drxk_hard.c
@@ -6211,6 +6211,14 @@ static int drxk_set_parameters(struct dvb_frontend *fe,
        u32 IF;
 
        dprintk(1, "\n");
+
+       if (!fe->ops.tuner_ops.get_if_frequency) {
+               printk(KERN_ERR
+                      "drxk: Error: get_if_frequency() not defined at tuner. Can't work without it!\n");
+               return -EINVAL;
+       }
+
+
        if (fe->ops.i2c_gate_ctrl)
                fe->ops.i2c_gate_ctrl(fe, 1);
        if (fe->ops.tuner_ops.set_params)
@@ -6218,7 +6226,7 @@ static int drxk_set_parameters(struct dvb_frontend *fe,
        if (fe->ops.i2c_gate_ctrl)
                fe->ops.i2c_gate_ctrl(fe, 0);
        state->param = *p;
-       fe->ops.tuner_ops.get_frequency(fe, &IF);
+       fe->ops.tuner_ops.get_if_frequency(fe, &IF);
        Start(state, 0, IF);
 
        /* printk(KERN_DEBUG "drxk: %s IF=%d done\n", __func__, IF); */

diff --git a/drivers/media/dvb/frontends/tda18271c2dd.c b/drivers/media/dvb/frontends/tda18271c2dd.c
index 0384e8da4f5ea9ec66c83058031b1d1e52dffe8a..1b1bf200c55c4b1c65dea314d5abcffcf89e7027 100644 (file)
--- a/drivers/media/dvb/frontends/tda18271c2dd.c
+++ b/drivers/media/dvb/frontends/tda18271c2dd.c
@@ -1195,7 +1195,7 @@ static int GetSignalStrength(s32 *pSignalStrength, u32 RFAgc, u32 IFAgc)
 }
 #endif
 
-static int get_frequency(struct dvb_frontend *fe, u32 *frequency)
+static int get_if_frequency(struct dvb_frontend *fe, u32 *frequency)
 {
        struct tda_state *state = fe->tuner_priv;
 
@@ -1222,7 +1222,7 @@ static struct dvb_tuner_ops tuner_ops = {
        .sleep             = sleep,
        .set_params        = set_params,
        .release           = release,
-       .get_frequency     = get_frequency,
+       .get_if_frequency  = get_if_frequency,
        .get_bandwidth     = get_bandwidth,
 };