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From: Mark Brown <broonie@kernel.org>
To: "Gupta, Pekon" <pekon@ti.com>
Cc: "thomas.langer@lantiq.com" <thomas.langer@lantiq.com>,
	"linux-mtd@lists.infradead.org" <linux-mtd@lists.infradead.org>,
	"spi-devel-general@lists.sourceforge.net"
	<spi-devel-general@lists.sourceforge.net>,
	"Poddar, Sourav" <sourav.poddar@ti.com>,
	Trent Piepho <tpiepho@gmail.com>,
	yuhang wang <wangyuhang2014@gmail.com>
Subject: Re: support DUAL and QUAD[patch v1]
Date: Mon, 22 Jul 2013 10:33:42 +0100	[thread overview]
Message-ID: <20130722093342.GJ9858@sirena.org.uk> (raw)
In-Reply-To: <20980858CB6D3A4BAE95CA194937D5E73E9E967D@DBDE04.ent.ti.com>


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On Fri, Jul 19, 2013 at 07:34:45PM +0000, Gupta, Pekon wrote:

> > Maybe it would make more sense to have a spi-rx-width and spi-tx-width
> > than can be set to 1, 2, 4, etc. bits instead of a bunch of properties
> > that are mutually exclusive?  Sooner or later someone is going to want
> > 8 bits.

> Then it would not remain a serial interface (Serial Peripheral Interface),
> rather it would be more of parallel memory like interface.
> And you would not like to use SPI controller for it, instead you would use
> On-chip General Purpose External Interface controllers (like GPMC)
> because it gives you more options to tweak and configure.

It's still not beyoond the bounds of possibility, and of course some
bright spark might decide to use 3 wires.  Unless it's expensive to do
so in some way it seems better to keep the interface as generic as
possible even if we've no expectation that some of the flexibility will
be used.

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WARNING: multiple messages have this Message-ID (diff)
From: Mark Brown <broonie@kernel.org>
To: "Gupta, Pekon" <pekon@ti.com>
Cc: "thomas.langer@lantiq.com" <thomas.langer@lantiq.com>,
	"linux-mtd@lists.infradead.org" <linux-mtd@lists.infradead.org>,
	"spi-devel-general@lists.sourceforge.net"
	<spi-devel-general@lists.sourceforge.net>,
	"Poddar, Sourav" <sourav.poddar@ti.com>,
	Trent Piepho <tpiepho@gmail.com>,
	yuhang wang <wangyuhang2014@gmail.com>
Subject: Re: support DUAL and QUAD[patch v1]
Date: Mon, 22 Jul 2013 10:33:42 +0100	[thread overview]
Message-ID: <20130722093342.GJ9858@sirena.org.uk> (raw)
In-Reply-To: <20980858CB6D3A4BAE95CA194937D5E73E9E967D@DBDE04.ent.ti.com>

[-- Attachment #1: Type: text/plain, Size: 934 bytes --]

On Fri, Jul 19, 2013 at 07:34:45PM +0000, Gupta, Pekon wrote:

> > Maybe it would make more sense to have a spi-rx-width and spi-tx-width
> > than can be set to 1, 2, 4, etc. bits instead of a bunch of properties
> > that are mutually exclusive?  Sooner or later someone is going to want
> > 8 bits.

> Then it would not remain a serial interface (Serial Peripheral Interface),
> rather it would be more of parallel memory like interface.
> And you would not like to use SPI controller for it, instead you would use
> On-chip General Purpose External Interface controllers (like GPMC)
> because it gives you more options to tweak and configure.

It's still not beyoond the bounds of possibility, and of course some
bright spark might decide to use 3 wires.  Unless it's expensive to do
so in some way it seems better to keep the interface as generic as
possible even if we've no expectation that some of the flexibility will
be used.

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 836 bytes --]

  reply	other threads:[~2013-07-22  9:33 UTC|newest]

Thread overview: 40+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-07-10  8:34 SPI: support DUAL and QUAD[patch v1] yuhang wang
2013-07-10  8:34 ` yuhang wang
     [not found] ` <CAHSAbzP0Nc1ahf_ra6yDuMvV998_+EGcUOGDv5ifKaagYf+NOg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-07-16  8:08   ` Gupta, Pekon
2013-07-16  8:08     ` Gupta, Pekon
     [not found]     ` <20980858CB6D3A4BAE95CA194937D5E73E9E84D2-yXqyApvAXouIQmiDNMet8wC/G2K4zDHf@public.gmane.org>
2013-07-16  8:59       ` yuhang wang
2013-07-16  8:59         ` yuhang wang
     [not found]         ` <CAHSAbzMDOWo5oBqUHqMxybuDwUjFbczYwN+85gH+rxZ9z8u2Pw-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-07-16  9:11           ` Gupta, Pekon
2013-07-16  9:11             ` Gupta, Pekon
     [not found]             ` <20980858CB6D3A4BAE95CA194937D5E73E9E851E-yXqyApvAXouIQmiDNMet8wC/G2K4zDHf@public.gmane.org>
2013-07-16 10:12               ` thomas.langer-th3ZBGNqt+7QT0dZR+AlfA
2013-07-16 10:12                 ` thomas.langer
     [not found]                 ` <593AEF6C47F46446852B067021A273D6D93B49E1-6yu8tajIPx7U45ihrnOXy0EOCMrvLtNR@public.gmane.org>
2013-07-16 11:20                   ` Gupta, Pekon
2013-07-16 11:20                     ` Gupta, Pekon
     [not found]                     ` <20980858CB6D3A4BAE95CA194937D5E73E9E85D0-yXqyApvAXouIQmiDNMet8wC/G2K4zDHf@public.gmane.org>
2013-07-16 11:59                       ` yuhang wang
2013-07-16 11:59                         ` yuhang wang
2013-07-16 12:18                       ` thomas.langer-th3ZBGNqt+7QT0dZR+AlfA
2013-07-16 12:18                         ` thomas.langer
2013-07-18  1:58                       ` yuhang wang
2013-07-18  1:58                         ` yuhang wang
     [not found]                         ` <CAHSAbzP5jqHwCm0qhu=DiNzpP0swqWHsQ0=MnF+EKaSN22E5hg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-07-18  2:25                           ` Trent Piepho
2013-07-18  2:25                             ` Trent Piepho
     [not found]                             ` <CA+7tXihoZZhpoyvxj58c+Zi-Zy631kK5s-kDoSxPKq=ej0qyvA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-07-19  2:24                               ` yuhang wang
2013-07-19  2:24                                 ` yuhang wang
2013-07-19 19:34                               ` Gupta, Pekon
2013-07-19 19:34                                 ` Gupta, Pekon
2013-07-22  9:33                                 ` Mark Brown [this message]
2013-07-22  9:33                                   ` Mark Brown
     [not found]                                   ` <20130722093342.GJ9858-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
2013-07-22  9:56                                     ` Gupta, Pekon
2013-07-22  9:56                                       ` Gupta, Pekon
2013-07-22 10:32                                       ` Huang Shijie
2013-07-22 10:32                                         ` Huang Shijie
     [not found]                                         ` <51ED0A57.4060105-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
2013-07-22 11:21                                           ` thomas.langer-th3ZBGNqt+7QT0dZR+AlfA
2013-07-22 11:21                                             ` thomas.langer
2013-07-22 12:55                                             ` Gupta, Pekon
2013-07-22 12:55                                               ` Gupta, Pekon
     [not found]                                               ` <20980858CB6D3A4BAE95CA194937D5E73E9ECAFC-yXqyApvAXouIQmiDNMet8wC/G2K4zDHf@public.gmane.org>
2013-07-23  2:24                                                 ` Huang Shijie
2013-07-23  2:24                                                   ` Huang Shijie
     [not found]                                       ` <20980858CB6D3A4BAE95CA194937D5E73E9EC9B1-yXqyApvAXouIQmiDNMet8wC/G2K4zDHf@public.gmane.org>
2013-07-27 11:35                                         ` yuhang wang
2013-07-27 11:35                                           ` yuhang wang
2013-07-16  9:29         ` Mark Brown
2013-07-16  9:29           ` Mark Brown

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