linux-kernel - Re: [PATCH] regulator: ti-abb: Add support for interleaved LDO registers

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20140121215624.GC17314@sirena.org.uk>
Date:	Tue, 21 Jan 2014 21:56:24 +0000
From:	Mark Brown <broonie@...nel.org>
To:	Nishanth Menon <nm@...com>
Cc:	devicetree@...r.kernel.org, linux-doc@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH] regulator: ti-abb: Add support for interleaved LDO
 registers

On Tue, Jan 21, 2014 at 02:06:25PM -0600, Nishanth Menon wrote:

> Without this change, on DRA7 I get:
> [    0.579500] abb_mpu: 1060 <--> 1210 mV
> [    0.580321] abb_ivahd: 1055 <--> 1250 mV
> [    0.580583] ti_abb 4ae07e20.regulator-abb-dspeve: can't request
> region for resource [mem 0x4ae07e20-0x4ae07e2f]
> [    0.580610] ti_abb: probe of 4ae07e20.regulator-abb-dspeve failed
> with error -16
> [    0.581216] abb_gpu: 1090 <--> 1280 mV

OK, that's not to do with nocache, that's to do with duplicate
request_mem_region() calls.  Of course the trick here is that if the
other thing that requests the memory region doesn't do it then we have a
problem.  

I really can't help thinking that a system controller node as the parent
is going to make things happier for devices that share this register
bank.  I guess it might be possible to also do it with single register
memory regions but I'd not be surprised if that wasn't possible and it
doesn't seem as idiomatic.

Download attachment "signature.asc" of type "application/pgp-signature" (837 bytes)