Do you have any comments on this, Mauro? Assuming that Mauro is OK with this change, (since he is the author of this driver) then yes - please resubmit the patch with some explanation within comments inline or within the commit message. Best regards, Mike Krufky On Mon, Sep 30, 2013 at 12:42 PM, Jiří Pinkava <j-pi@xxxxxxxxx> wrote: > Mike, > > unfortunately no documentation can be referenced except preliminary > version of > datasheet (1).This change is based on lucky guess and supported by lot of > testing on real hardware. > > This change add support for devices with Xtal frequency bellow 28.8MHz. > > From Nint are computed values of Ni and Si. For 28.8MHz crystal can > reach up to 12 / 3 (Ni / Si). Tuner supports crystals with frequencies > (1) 12, 16, 20, 20.48, 24, 27, 28.8, 32 MHz, but this kind of device is > rare to found. > Allowing Ni to go up to 15 instead of only 12 should be safe and for 15 > / 3 (Ni / Si) > we can compute limit for Nint = max(Ni) * 4 + max(Si) + 13 = 76. > > If This is sufficient and acceptable explanation I can add some sort of > documentation into patch and resend it (both patches, I can prove I'm > right :) > > (1) > http://rtl-sdr.com/wp-content/uploads/2013/04/R820T_datasheet-Non_R-20111130_unlocked.pdf > >> Jiří, >> >> Do you have any documentation that supports this value change? >> Changing this value affects the algorithm, and we'd be happier making >> this change if the patch included some better description and perhaps >> a reference explaining why the new value is correct. >> >> Regards, >> >> Mike Krufky >> >> On Sun, Sep 29, 2013 at 6:45 AM, Jiří Pinkava <j-pi@xxxxxxxxx> wrote: >>> >>> Use full range of VCO parameters, fixes tunning for some frequencies. >>> --- >>> drivers/media/tuners/r820t.c | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/drivers/media/tuners/r820t.c b/drivers/media/tuners/r820t.c >>> index 1c23666..e25c720 100644 >>> --- a/drivers/media/tuners/r820t.c >>> +++ b/drivers/media/tuners/r820t.c >>> @@ -637,7 +637,7 @@ static int r820t_set_pll(struct r820t_priv *priv, >>> enum v4l2_tuner_type type, >>> vco_fra = pll_ref * 129 / 128; >>> } >>> >>> - if (nint > 63) { >>> + if (nint > 76) { >>> tuner_info("No valid PLL values for %u kHz!\n", freq); >>> return -EINVAL; >>> } >>> -- >>> 1.8.3.2 >>> >>> > -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
