Re: [PATCH 3/3] Input: applespi: Add trace_event module param for early tracing.

[Life is hard, and then you die]

  Hi Dmitry,

On Wed, Feb 17, 2021 at 12:26:18PM -0800, Dmitry Torokhov wrote:
> 
> On Wed, Feb 17, 2021 at 11:07:18AM -0800, Ronald Tschalär wrote:
> > The problem is that tracing can't be set via sysfs until the module is
> > loaded, at which point the keyboard and trackpad initialization commands
> > have already been run and hence tracing can't be used to debug problems
> > here.
> > 
> > Adding this param allows tracing to be enabled for messages sent and
> > received during module probing. It takes comma-separated list of events,
> > e.g.
> > 
> >   trace_event=applespi_tp_ini_cmd,applespi_bad_crc
> 
> You can unbind and rebind a device to a driver via sysfs as many times
> as needed (see bind and unbind driver sysfs attributes), so I believe

Hmm, I'm going to have to play with that a bit, but one place it still
won't help I think is something we ran into in practise: init was
failing during boot, but was successfull later on.


  Cheers,

  Ronald