On 20/07/15 18:47, Adam Lee wrote: > Hello, here is some more context from the TPS65950's TRM [1]. > > Quoting from section 15.3.1.2.1 VUSB3V1 section: > > "VUSB3V1 is also used to bias analog multiplexers on the four MCPC > pins between the carkit and the MADC (supplied by VINTANA2)." > > > And from section 15.4.11. MADC Monitoring Using MCPC: > > "Four MCPC pins can be selected as analog conversion input pins by > setting the CARKIT_ANA_CTRL[3] SEL_MADC_MCPC bit." > > My patch addresses both (set the register, and enable 3v1). And yes it > has been tested on Gumstix Overo COMs (OMAP3 + TPS65950). > > Hope to hear from IIO maintainers! I dug the patch out of the archives. Looks clear enough to me. Could you resend the patch with linux-iio cc'd? I will want an Ack from Sebastian. Thanks, Jonathan > > [1] http://www.droid-developers.org/images/2/21/Tps65950_TRM.pdf > > On Fri, Jul 17, 2015 at 2:42 AM, Peter Meerwald <pmeerw@xxxxxxxxxx> wrote: >> Hello, >> >> adding linux-iio... >> >>> To get a chance of this patch being considered for inclusion, you >>> should send this to the maintainers of the phy and iio framework. >>> There is a high chance, that none of them will see your mail. >>> >>> On Thu, Jul 16, 2015 at 03:20:27PM -0700, Adam YH Lee wrote: >>>> MADC[3:6] reads incorrect values without these two following changes: >>> >>> uhm MADC[3:6] are externally available analog inputs. Your >>> change will result in them being tied to the USB module. >> >> change regarding TWL4030_USB_SEL_MADC_MCPC is necessary at >> least for some hardware revisions to get proper ADC values >> >>>> - enable the 3v1 bias regulator for ADC[3:6] >>> >>> The regulator is not required for correct MADC functionality, but >>> for correct USB measureing. The regulator should not be requested >>> by the madc module, but by the usb module, which is connected to >>> the madc. >> >> in my experience, the MADC exhibits several strange things, I wouldn't be >> surprised that this bias is somehow necessary for operation even if it is >> not what the spec says -- has this been tested? >> >>>> - configure ADC[3:6] lines as input, not as USB >>> >>> I don't think that should be done for all boards. >>> >>>> [...] >>> >>> -- Sebastian >>> >> >> -- >> >> Peter Meerwald >> +43-664-2444418 (mobile) > -- > To unsubscribe from this list: send the line "unsubscribe linux-iio" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
