On Fri, Jul 30, 2010 at 8:02 AM, Jon Smirl <jonsmirl@xxxxxxxxx> wrote: > On Fri, Jul 30, 2010 at 7:54 AM, Maxim Levitsky <maximlevitsky@xxxxxxxxx> wrote: >> On Fri, 2010-07-30 at 07:51 -0400, Jon Smirl wrote: >>> On Fri, Jul 30, 2010 at 7:36 AM, Maxim Levitsky <maximlevitsky@xxxxxxxxx> wrote: >>> > On Thu, 2010-07-29 at 23:46 -0400, Andy Walls wrote: >>> >> On Thu, 2010-07-29 at 22:39 -0400, Jon Smirl wrote: >>> >> > On Thu, Jul 29, 2010 at 10:17 PM, Maxim Levitsky >>> >> > <maximlevitsky@xxxxxxxxx> wrote: >>> >> > > note that error_adjustment module option is added. >>> >> > > This allows to reduce input samples by a percent. >>> >> > > This makes input on my system more correct. >>> >> > > >>> >> > > Default is 4% as it works best here. >>> >> > > >>> >> > > Note that only normal input is adjusted. I don't know >>> >> > > what adjustments to apply to fan tachometer input. >>> >> > > Maybe it is accurate already. >>> >> > >>> >> > Do you have the manual for the ENE chip in English? or do you read Chinese? >>> >> >>> >> The datasheet for a similar chip, the KB3700, is out there in English, >>> >> but it doesn't have CIR. >>> >> >>> >> You might find these links mildly interesting: >>> >> >>> >> http://www.coreboot.org/Embedded_controller >>> >> http://wiki.laptop.org/go/Embedded_controller >>> >> http://lists.laptop.org/pipermail/openec/2008-July/000108.html >>> > >>> > Nope, I have read that. >>> >> >>> >> Regards, >>> >> Andy >>> >> >>> >> > Maybe you can figure out why the readings are off by 4%. I suspect >>> >> > that someone has set a clock divider wrong when programming the chip. >>> >> > For example setting the divider for a 25Mhz clock when the clock is >>> >> > actually 26Mhz would cause the error you are seeing. Or they just made >>> >> > a mistake in computing the divisor. It is probably a bug in the BIOS >>> >> > of your laptop. If that's the case you could add a quirk in the >>> >> > system boot code to fix the register setting. >>> > >>> > I figured out how windows driver compensates for the offset, and do the >>> > same in my driver. I think the problem is solved. >>> > >>> >>> Should that be a <= or >= instead of !=? >>> + if (pll_freq != 1000) >> >> This is how its done in windows driver. > > That doesn't mean it is bug free. > > Experimenting with changing the PLL frequency register may correct the > error. Try taking 96% of pll_freq and write it back into these > register. This would be easy to fix with a manual. The root problem is > almost certainly a bug in the way the PLLs were programmed. > > I don't like putting in fudge factors like the 4% correction. What > happens if a later version of the hardware has fixed firmware? I > normal user is never going to figure out that they need to change the > fudge factor. > > + pll_freq = (ene_hw_read_reg(dev, ENE_PLLFRH) << 4) + > + (ene_hw_read_reg(dev, ENE_PLLFRL) >> 2); I can understand the shift of the high bits, but that shift of the low bits is unlikely. A manual would tell us if it is right. > + > > >>> >>> Programming the PLL wrong would cause the 4% error. >>> >>> hw_revision = ene_hw_read_reg(dev, ENE_HW_VERSION); >>> old_ver = ene_hw_read_reg(dev, ENE_HW_VER_OLD); >>> >>> + pll_freq = (ene_hw_read_reg(dev, ENE_PLLFRH) << 4) + >>> + (ene_hw_read_reg(dev, ENE_PLLFRL) >> 2); >>> + >>> + if (pll_freq != 1000) >>> + dev->rx_period_adjust = 4; >>> + else >>> + dev->rx_period_adjust = 2; >>> + >>> + >>> + ene_printk(KERN_NOTICE, "PLL freq = %d\n", pll_freq); >>> + >>> if (hw_revision == 0xFF) { >>> >>> >>> >>> > >>> > Best regards, >>> > Maxim Levitsky >>> > >>> > >>> >>> >>> >> >> >> > > > > -- > Jon Smirl > jonsmirl@xxxxxxxxx > -- Jon Smirl jonsmirl@xxxxxxxxx -- 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
