[PATCH 2/3] arm: tegra: enable igb, stmpe, i2c chardev, spidev, lm95245, pwm leds

Marcel Ziswiler marcel at ziswiler.com
Mon Jun 9 15:16:13 PDT 2014


On 06/04/2014 01:17 PM, Mark Brown wrote:
> You're saying you're controlling it from userspace.  This is a
> particular detail of what you are doing in your system.  You happen to
> want to control the devices you are hanging off the system with
> userspace drivers but that's just what you're doing right now.

Sorry, I don't get it. Yes, spidev is to control stuff from user space 
just like i2c-dev however bad that might sound.

> No, that's in the controller node - the chip selects are described
> there.  The child node references a chip select number that the master
> has and describes what's connected to that chip select.

Well, unfortunately SPI without any chip select is just plain simply 
useless. It won't work.

> It's a perfectly fine way of controlling things from userspace if that's
> a sensible way of controlling devices but that does not mean you should
> describe it in the device tree in that fashion.

Only that without describing such a chip select in the device tree 
spidev won't ever work.

I don't see us reaching any consensus here therefore I retreat. I will 
re-submit the whole thing without spidev however sad having to see that 
useful feature being dropped.



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