Re: [PATCH v9 4/7] staging: fpga manager: add sysfs interface document

[Pavel Machek <pavel@denx.de>]

On Fri 2015-07-24 07:39:15, atull wrote:
> On Fri, 24 Jul 2015, Pavel Machek wrote:
> 
> Hi Pavel,
> 
> Thanks for your your feedback in cleaning up these docs.
> 
> > Hi!
> > 
> > > +What:		/sys/class/fpga_manager/<fpga>/state
> > > +Date:		July 2015
> > > +KernelVersion:	4.2
> > > +Contact:	Alan Tull <atull@opensource.altera.com>
> > > +Description:	Read fpga manager state as a string.
> > 
> > fpga->FPGA.
> 
> Yep
> 
> > 
> > > +		Valid states may vary by manufacturer; superset is:
> > > +		* unknown		= can't determine state
> > > +		* power off		= FPGA power is off
> > > +		* power up		= FPGA reports power is up
> > > +		* reset			= FPGA held in reset state
> > > +		* firmware request	= firmware class request in progress
> > > +		* firmware request error = firmware request failed
> > > +		* write init		= FPGA being prepared for programming
> > > +		* write init error	= Error while preparing FPGA for
> > > +					  programming
> > > +		* write			= FPGA ready to receive image data
> > > +		* write error		= Error while programming
> > > +		* write complete	= Doing post programming steps
> > > +		* write complete error	= Error while doing post programming
> > > +		* operating		= FPGA is programmed and operating
> > 
> 
> If I can make my intent clear, maybe we can figure out what will be most
> useful here.  
> 
> The intent is to provide enough detail that if something goes wrong with
> the FPGA programming (something that the driver can't take care of) then 
> userspace can know that.  Such as if the firmware request fails, that 
> could be due to not being able to find the firmware file.
> 
> > This will need some more details. "firmware request" is hardly a
> > hardware state, does it belong here? 
> 
> This is a superset of FPGA states and fpga manager driver states as the
> fpga manager driver is walking through the steps to get the FPGA into
> a known operating state.  So it's a sequence, though some steps may get
> skipped. If there is an error, then userspace can know what step failed.
> 
> Maybe this should be separated into fpga_state for hardware state and
> fpga_mgr_status (to report what step of progress the fpga manager driver
> is at during programming).  I want this to be useful and still not be 
> device (FPGA) specific.
> 
> > Is power off or on while firmware
> > is being requested? 
> 
> On.  It's a sequence.

Aha. Ok, so maybe noting that states normally go in the sequence (with
exception of various errors) would be enough?

Thanks,
									Pavel
-- 
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