Robert: OK, I have a overlay bug for you. I have a SPI0 application, where I don't want to use the CS0 output from the peripheral, but would rather bit bang the chip select line CS0 on the same pin as a GPIO. I have three SPI devices sharing the SPI bus, so I need to have three chip select lines, that are all GPIO lines, but the first one is P9.17. (The BBB does not pin out peripheral CS1 line, so you need to do something like this, anytime you have more than two SPI slaves.)
On kernel 3.14, all I had to do was comment out the appropriate lines regarding P9.17 in the "BB-SPIDEV0-00A0.dts" and the SPI interface would not claim the CS line, and I could then claim it as a GPIO and everything worked fine. Under kernel 4.1, doing the same edit to the file and creating a ".dtbo", even though I only reference the three core bus lines (clock, DI and DO) in the ".dts" the spi driver still claims all four lines, including the CS0, and I have a conflict on P9.17, so my GPIO ".dtbo" won't load, and things go downhill from there. The problem pin is P9.17, aka pin95, offset 0x17c. Debian Image 2015-06-17 uname -a= Linux BBB2 4.1.0-rc8-bone9 #1 Wed Jun 17 00:05:43 UTC 2015 armv7l --- Graham == -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
