Messages in this thread | | | Date | Wed, 13 May 2015 12:16:25 +0200 | From | Maxime Ripard <> | Subject | Re: [PATCH] spi: Add option to bind spidev to all chipselects |
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Hi,
On Wed, May 13, 2015 at 09:34:41AM -0000, Michal Suchanek wrote: > Bypass the check if CS is in use for spidev devices if CONFIG_SPIDEV_SHADOW is > set. Rename spidev devices to avoid sysfs conflict. > > This allows dynamically loading SPI device overlays or communicating > with SPI devices configured by a kernel driver from userspace. > > Signed-off-by: Michal Suchanek <hramrach@gmail.com>
Output from checkpatch: total: 2 errors, 4 warnings, 4 checks, 157 lines checked
...
I told you a few times already to run checkpatch before sending your patches, apparently you make a point at ignoring me. Fine.
That being said, I'm not sure this is the right approach, or at least, it doesn't solve anything. If SPIDEV_SHADOW is not set, you will still have the same issue with addition of new devices on previously unused chip selects, and where we have an spidev device now.
What I think we should do is, when a new device is created, we just lookup the modalias of the spi_device associated to it.
If that modalias is "spidev", then unregister the spidev device, register the new device, you're done. If not, return an error.
On the SPIDEV_SHADOW stuff itself, I'm not sure this is such a good idea. There's a good chance it will break the driver by doing stuff behind its back, possibly in a way that will harm the whole kernel, and it's something we usually try to avoid.
Maxime
-- Maxime Ripard, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com [unhandled content-type:application/pgp-signature] | |