On Mon, 10 Oct 2016, Jacek Anaszewski wrote: > On 10/10/2016 03:24 PM, Alexander Kurz wrote: > > > > > > On Mon, 10 Oct 2016, Jacek Anaszewski wrote: > > > > > Hi Alexander, > > > > > It should write value << 3 to the register 52. > > > > > > > > > > According to the documentation [0] LEDKP0, LEDKP1 and LEDKP2 > > > > > are driven by bits 9,10 and 11 respectively. The calculations > > > > > don't seem to be in line with that. Could you point what I > > > > > am missing? > > LEDKP0, LEDKP1 and LEDKP2 controlles the led current setting, but ... > > > > > > > > > > > > [0] http://www.nxp.com/files/analog/doc/data_sheet/MC13892.pdf > > > > > > > > The numbering mentioned in the DT documentation is used as offset > > > > for the device specific struct mc13xxx_led_devtype.led_min > > > > > if (of_property_read_u32(child, "reg", &tmp)) > > > > > continue; > > > > > pdata->led[i].id = leds->devtype->led_min + tmp; > > > > e.g. MC13892_LED_KP = MC13892_LED_MD + 2 > > > > > > > > Hope this clarifies your question, > > > > > > Thanks but not entirely - what with the second part of question related > > > to the register layout? > > The LED brightness is controlled via the duty cycle bits allowing > > 64 brightness values, setting bits/registers like > > LED | reg | bits > > -----+-----+------ > > main | 0 | 3..8 > > aux | 0 | 15..20 > > kp | 1 | 3..8 > > red | 2 | 3..8 > > green| 2 | 15..20 > > blue | 3 | 3..8 So, I have probably introduced some confusion by using "LED Control #reg" as "reg" from Table 163-166. > So it doesn't seem to reflect what is shown in the Table 164. > on the site 148 of the document I mentioned in the previous > message. Could you please give a reference to the documentation > you're using? Exactly the same datasheet. Again, brightness controlling bits with verbatim Register numbering LED | Register | LED Control | bits -----+----------+-------------+----- main | 51 | 0 | 3..8 aux | 51 | 0 | 15..20 kp | 52 | 1 | 3..8 red | 53 | 2 | 3..8 green| 53 | 2 | 15..20 blue | 54 | 3 | 3..8 Cheers, Alexander > > -- > Best regards, > Jacek Anaszewski > -- To unsubscribe from this list: send the line "unsubscribe linux-leds" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
