All of lore.kernel.org
 help / color / mirror / Atom feed
From: david@lechnology.com (David Lechner)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 1/3] ARM: DTS: da850: add node for spi0
Date: Fri, 15 Apr 2016 16:20:51 -0500	[thread overview]
Message-ID: <57115B33.90509@lechnology.com> (raw)
In-Reply-To: <31522.1460751389@turing-police.cc.vt.edu>

On 04/15/2016 03:16 PM, Valdis.Kletnieks at vt.edu wrote:
> On Fri, 15 Apr 2016 11:17:55 -0500, David Lechner said:
>
>> I omitted this on purpose. For my use case, I am using the SPI as
>> write-only,
>
> So your SPI accesses are fire-and-forget, and nothing ever comes back?

Yes.

> Seems a very dangerous way to design the use case, with no feedback if
> something suddenly goes pear-shaped...

You should tell Sitronix. This is how their display controllers work.

>
> Or do you have ways to verify the status via some method other than SPI?
>

Nope.



I'm working with LEGO MINDSTORMS EV3, a mass-produced robotics system. 
It is what it is. And I have a logic analyzer for when things go 
pear-shaped. ;-)

WARNING: multiple messages have this Message-ID (diff)
From: David Lechner <david-nq/r/kbU++upp/zk7JDF2g@public.gmane.org>
To: Valdis.Kletnieks-PjAqaU27lzQ@public.gmane.org
Cc: Sekhar Nori <nsekhar-l0cyMroinI0@public.gmane.org>,
	Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>,
	Pawel Moll <pawel.moll-5wv7dgnIgG8@public.gmane.org>,
	Mark Rutland <mark.rutland-5wv7dgnIgG8@public.gmane.org>,
	Ian Campbell
	<ijc+devicetree-KcIKpvwj1kUDXYZnReoRVg@public.gmane.org>,
	Kumar Gala <galak-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>,
	Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>,
	Kevin Hilman <khilman-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>,
	devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org,
	linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: Re: [PATCH 1/3] ARM: DTS: da850: add node for spi0
Date: Fri, 15 Apr 2016 16:20:51 -0500	[thread overview]
Message-ID: <57115B33.90509@lechnology.com> (raw)
In-Reply-To: <31522.1460751389-+bZmOdGhbsPr6rcHtW+onFJE71vCis6O@public.gmane.org>

On 04/15/2016 03:16 PM, Valdis.Kletnieks-PjAqaU27lzQ@public.gmane.org wrote:
> On Fri, 15 Apr 2016 11:17:55 -0500, David Lechner said:
>
>> I omitted this on purpose. For my use case, I am using the SPI as
>> write-only,
>
> So your SPI accesses are fire-and-forget, and nothing ever comes back?

Yes.

> Seems a very dangerous way to design the use case, with no feedback if
> something suddenly goes pear-shaped...

You should tell Sitronix. This is how their display controllers work.

>
> Or do you have ways to verify the status via some method other than SPI?
>

Nope.



I'm working with LEGO MINDSTORMS EV3, a mass-produced robotics system. 
It is what it is. And I have a logic analyzer for when things go 
pear-shaped. ;-)
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

WARNING: multiple messages have this Message-ID (diff)
From: David Lechner <david@lechnology.com>
To: Valdis.Kletnieks@vt.edu
Cc: Sekhar Nori <nsekhar@ti.com>, Rob Herring <robh+dt@kernel.org>,
	Pawel Moll <pawel.moll@arm.com>,
	Mark Rutland <mark.rutland@arm.com>,
	Ian Campbell <ijc+devicetree@hellion.org.uk>,
	Kumar Gala <galak@codeaurora.org>,
	Russell King <linux@arm.linux.org.uk>,
	Kevin Hilman <khilman@kernel.org>,
	devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/3] ARM: DTS: da850: add node for spi0
Date: Fri, 15 Apr 2016 16:20:51 -0500	[thread overview]
Message-ID: <57115B33.90509@lechnology.com> (raw)
In-Reply-To: <31522.1460751389@turing-police.cc.vt.edu>

On 04/15/2016 03:16 PM, Valdis.Kletnieks@vt.edu wrote:
> On Fri, 15 Apr 2016 11:17:55 -0500, David Lechner said:
>
>> I omitted this on purpose. For my use case, I am using the SPI as
>> write-only,
>
> So your SPI accesses are fire-and-forget, and nothing ever comes back?

Yes.

> Seems a very dangerous way to design the use case, with no feedback if
> something suddenly goes pear-shaped...

You should tell Sitronix. This is how their display controllers work.

>
> Or do you have ways to verify the status via some method other than SPI?
>

Nope.



I'm working with LEGO MINDSTORMS EV3, a mass-produced robotics system. 
It is what it is. And I have a logic analyzer for when things go 
pear-shaped. ;-)

  reply	other threads:[~2016-04-15 21:20 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-04-13 22:30 [PATCH 0/3] More small davinci device tree fixes David Lechner
2016-04-13 22:30 ` David Lechner
2016-04-13 22:30 ` [PATCH 1/3] ARM: DTS: da850: add node for spi0 David Lechner
2016-04-13 22:30   ` David Lechner
2016-04-15 10:24   ` Sekhar Nori
2016-04-15 10:24     ` Sekhar Nori
2016-04-15 10:24     ` Sekhar Nori
2016-04-15 16:17     ` David Lechner
2016-04-15 16:17       ` David Lechner
2016-04-15 20:16       ` Valdis.Kletnieks at vt.edu
2016-04-15 20:16         ` Valdis.Kletnieks
2016-04-15 20:16         ` Valdis.Kletnieks-PjAqaU27lzQ
2016-04-15 21:20         ` David Lechner [this message]
2016-04-15 21:20           ` David Lechner
2016-04-15 21:20           ` David Lechner
2016-04-18  5:55       ` Sekhar Nori
2016-04-18  5:55         ` Sekhar Nori
2016-04-18  5:55         ` Sekhar Nori
2016-04-13 22:30 ` [PATCH 2/3] ARM: DTS: da850: disable mdio and eth0 by default David Lechner
2016-04-13 22:30   ` David Lechner
2016-04-13 22:30   ` David Lechner
2016-04-15 10:25   ` Sekhar Nori
2016-04-15 10:25     ` Sekhar Nori
2016-04-15 10:25     ` Sekhar Nori
2016-04-13 22:30 ` [PATCH 3/3] ARM: DTS: da850: There are 101 interrupts David Lechner
2016-04-13 22:30   ` David Lechner
2016-04-15 10:26   ` Sekhar Nori
2016-04-15 10:26     ` Sekhar Nori
2016-04-15 10:26     ` Sekhar Nori
2016-04-14 22:20 ` [PATCH 0/3] More small davinci device tree fixes Kevin Hilman
2016-04-14 22:20   ` Kevin Hilman
2016-04-14 22:20   ` Kevin Hilman

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=57115B33.90509@lechnology.com \
    --to=david@lechnology.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.