[PATCH RFC 04/11] media: vidtv: fix frequency tuning logic

Mauro Carvalho Chehab
2020-09-14T09:04:12Z

Right now, there are some issues at the tuning logic:

1) the config struct is not copied at the tuner driver.
so, it won't use any frequency table at all;
2) the code that checks for frequency shifts is called
at set_params. So, lock_status will never be zeroed;
3) the signal strength will also report a strong
signal, even if not tuned;
4) the logic is not excluding non-set frequencies.

Fix those issues.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
---
.../media/test-drivers/vidtv/vidtv_tuner.c | 22 ++++++++++++++-----
1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/drivers/media/test-drivers/vidtv/vidtv_tuner.c b/drivers/media/test-drivers/vidtv/vidtv_tuner.c
index 39e848ae5836..0f397fe12989 100644
--- a/drivers/media/test-drivers/vidtv/vidtv_tuner.c
+++ b/drivers/media/test-drivers/vidtv/vidtv_tuner.c
@@ -120,7 +120,7 @@ vidtv_tuner_get_dev(struct dvb_frontend *fe)
return i2c_get_clientdata(fe->tuner_priv);
}

-static s32 vidtv_tuner_check_frequency_shift(struct dvb_frontend *fe)
+static int vidtv_tuner_check_frequency_shift(struct dvb_frontend *fe)
{
struct vidtv_tuner_dev *tuner_dev = vidtv_tuner_get_dev(fe);
struct dtv_frontend_properties *c = &fe->dtv_property_cache;
@@ -156,6 +156,8 @@ static s32 vidtv_tuner_check_frequency_shift(struct dvb_frontend *fe)
}

for (i = 0; i < array_sz; i++) {
+ if (!valid_freqs[i])
+ break;
shift = abs(c->frequency - valid_freqs[i]);

if (!shift)
@@ -177,6 +179,7 @@ static int
vidtv_tuner_get_signal_strength(struct dvb_frontend *fe, u16 *strength)
{
struct dtv_frontend_properties *c = &fe->dtv_property_cache;
+ struct vidtv_tuner_dev *tuner_dev = vidtv_tuner_get_dev(fe);
const struct vidtv_tuner_cnr_to_qual_s *cnr2qual = NULL;
struct device *dev = fe->dvb->device;
u32 array_size = 0;
@@ -184,6 +187,10 @@ vidtv_tuner_get_signal_strength(struct dvb_frontend *fe, u16 *strength)
u32 i;

shift = vidtv_tuner_check_frequency_shift(fe);
+ if (shift < 0) {
+ tuner_dev->hw_state.lock_status = 0;
+ return 0;
+ }

switch (c->delivery_system) {
case SYS_DVBT:
@@ -224,10 +231,6 @@ vidtv_tuner_get_signal_strength(struct dvb_frontend *fe, u16 *strength)
*strength = cnr2qual[i].cnr_good;
return 0;
}
- if (shift < 0) { /* Channel not tuned */
- *strength = 0;
- return 0;
- }
/*
* Channel tuned at wrong frequency. Simulate that the
* Carrier S/N ratio is not too good.
@@ -288,6 +291,7 @@ static int vidtv_tuner_set_params(struct dvb_frontend *fe)
struct vidtv_tuner_dev *tuner_dev = vidtv_tuner_get_dev(fe);
struct vidtv_tuner_config config = tuner_dev->config;
struct dtv_frontend_properties *c = &fe->dtv_property_cache;
+ s32 shift;

u32 min_freq = fe->ops.tuner_ops.info.frequency_min_hz;
u32 max_freq = fe->ops.tuner_ops.info.frequency_max_hz;
@@ -305,6 +309,13 @@ static int vidtv_tuner_set_params(struct dvb_frontend *fe)
tuner_dev->hw_state.lock_status = TUNER_STATUS_LOCKED;

msleep_interruptible(config.mock_tune_delay_msec);
+
+ shift = vidtv_tuner_check_frequency_shift(fe);
+ if (shift < 0) {
+ tuner_dev->hw_state.lock_status = 0;
+ return shift;
+ }
+
return 0;
}

@@ -395,6 +406,7 @@ static int vidtv_tuner_i2c_probe(struct i2c_client *client,
&vidtv_tuner_ops,
sizeof(struct dvb_tuner_ops));

+ memcpy(&tuner_dev->config, config, sizeof(tuner_dev->config));
fe->tuner_priv = client;

return 0;
--
2.26.2