On 2018-01-17 16:02, Antti Palosaari wrote:
>
>
> On 01/17/2018 11:52 PM, Brad Love wrote:
>> Some tuners produce inverted spectrum, but the si2168 is not
>> currently set up to accept it. This adds an optional parameter
>> to set the frontend up to receive inverted spectrum.
>>
>> Parameter is optional and only boards who enable inversion
>> will utilize this.
>>
>> Signed-off-by: Brad Love <brad@xxxxxxxxxxxxxxxx>
>> ---
>> Changes since v1:
>> - Embarassing build failure due to missing declaration.
>>
>> drivers/media/dvb-frontends/si2168.c | 3 +++
>> drivers/media/dvb-frontends/si2168.h | 3 +++
>> 2 files changed, 6 insertions(+)
>>
>> diff --git a/drivers/media/dvb-frontends/si2168.c
>> b/drivers/media/dvb-frontends/si2168.c
>> index c041e79..048b815 100644
>> --- a/drivers/media/dvb-frontends/si2168.c
>> +++ b/drivers/media/dvb-frontends/si2168.c
>> @@ -213,6 +213,7 @@ static int si2168_set_frontend(struct
>> dvb_frontend *fe)
>> struct i2c_client *client = fe->demodulator_priv;
>> struct si2168_dev *dev = i2c_get_clientdata(client);
>> struct dtv_frontend_properties *c = &fe->dtv_property_cache;
>> + struct si2168_config *config = client->dev.platform_data;
>
> hmmm, are you sure platform data pointer points is const? I usually
> tend to store all config information to device state. Then there is no
> need to care if pointer is valid or not anymore.
>
> And inversion happens when those wires are cross-connected
It just dawned on me that the platform_data is stack allocated and
therefore not safe to access outside of probe. I will fix this momentarily.
I was informed by one of our hardware guys that the two models in patch
2/2 are inverted spectrum, so I guess they have wires cross-connected. I
can verify this again to be sure.
>
>> int ret;
>> struct si2168_cmd cmd;
>> u8 bandwidth, delivery_system;
>> @@ -339,6 +340,8 @@ static int si2168_set_frontend(struct
>> dvb_frontend *fe)
>> memcpy(cmd.args, "\x14\x00\x0a\x10\x00\x00", 6);
>> cmd.args[4] = delivery_system | bandwidth;
>> + if (config->spectral_inversion)
>> + cmd.args[5] |= 1;
>> cmd.wlen = 6;
>> cmd.rlen = 4;
>> ret = si2168_cmd_execute(client, &cmd);
>> diff --git a/drivers/media/dvb-frontends/si2168.h
>> b/drivers/media/dvb-frontends/si2168.h
>> index f48f0fb..d519edd 100644
>> --- a/drivers/media/dvb-frontends/si2168.h
>> +++ b/drivers/media/dvb-frontends/si2168.h
>> @@ -46,6 +46,9 @@ struct si2168_config {
>> /* TS clock gapped */
>> bool ts_clock_gapped;
>> +
>> + /* Inverted spectrum */
>> + bool spectral_inversion;
>> };
>> #endif
>>
>
