RE: [PATCH] OMAP3: MMC: Add mux for pins

From: "Pandita, Vikram" <vikram.pandita@ti.com>
To: Kevin Hilman <khilman@deeprootsystems.com>,
	"Hunter, Jon" <jon-hunter@ti.com>
Cc: Tony Lindgren <tony@atomide.com>,
	Hugo Vincent <hugo.vincent@gmail.com>,
	"linux-omap@vger.kernel.org" <linux-omap@vger.kernel.org>,
	"Chikkature Rajashekar, Madhusudhan" <madhu.cr@ti.com>
Subject: RE: [PATCH] OMAP3: MMC: Add mux for pins
Date: Thu, 18 Jun 2009 04:55:55 +0530	[thread overview]
Message-ID: <FCCFB4CDC6E5564B9182F639FC35608702F53D18E7@dbde02.ent.ti.com> (raw)
In-Reply-To: <87zlc6v56x.fsf@deeprootsystems.com>

>-----Original Message-----
>From: Kevin Hilman [mailto:khilman@deeprootsystems.com]
>Sent: Wednesday, June 17, 2009 5:58 PM
>To: Hunter, Jon
>Cc: Pandita, Vikram; Tony Lindgren; Hugo Vincent; linux-omap@vger.kernel.org; Chikkature Rajashekar,
>Madhusudhan
>Subject: Re: [PATCH] OMAP3: MMC: Add mux for pins
>
>Jon Hunter <jon-hunter@ti.com> writes:
>
>> Kevin Hilman wrote:
>>> "Pandita, Vikram" <vikram.pandita@ti.com> writes:
>>>
>>>>> -----Original Message-----
>>>>> From: Kevin Hilman [mailto:khilman@deeprootsystems.com]
>>>>>
>>>>>>> If some pins are always needed, and don't have alternative pinouts, then
>>>>>>> the common pins could be muxed in devices.c.
>>>>>> This is the algo we can use for MMC pin muxing in that case:
>>>>>>
>>>>>> MMC1: No pin has mux clash
>>>>>> 	Mux all 10 pins in devices.c
>>>>> Is this common across 34xx and 35xx?
>>>> Yes this is common.
>>>> Both are same OMAP3 marketed differently.
>>>
>>> Yes, but they are in different packages, so I was curious if the pin
>>> muxing is identical across the different packages.
>>
>> The ball/pad numbers may change due to the package, but the registers
>> used to configure the pin muxing and the pin muxing options will not
>> change. So from a software standpoint it is the same.
>>
>> The OMAP3530 is available in 3 packages, namely CBB, CBC and CUS
>> according to the data manual [1]. The OMAP3430 is only available in
>> the CBB package.
>>
>> What this means is that the name "N28_3430_MMC1_CLK", which associates
>> ball N28 with signal MMC1_CLK, is appliable to the OMAP3430 and
>> OMAP3530 CBB package, but not applicable to the OMAP3530 CBC and CUS
>> packages
>> as this ball number does not exist on these packages. This is simply a
>> difference in naming of the balls between the packages but does not
>> impact the pin muxing options.

So looks like I should keep the MMC mux under cpu_is_omap3430()
And not include 3530 as CBC and CUS may not be valid cases for this mux.

>
>OK, good.  Thanks for the clarification.
>
>Tony and I were thinking a few weeks back that we should drop the ball
>names from these mux options anyways as they don't really add any
>value, and seem to add more confusion.  Sounds like it's the right
>thing to do in this context.
>
>Kevin
>
>
>