From: mjg59@srcf.ucam.org (Matthew Garrett)
To: linux-arm-kernel@lists.infradead.org
Subject: ACPI
Date: Tue, 26 Nov 2013 14:45:32 +0000 [thread overview]
Message-ID: <20131126144532.GA10641@srcf.ucam.org> (raw)
In-Reply-To: <CACRpkdY+6dzs8MpKKtW-3kzsLkZjsit9SeN20k_33TAtVf3NEA@mail.gmail.com>
On Tue, Nov 26, 2013 at 01:43:40PM +0100, Linus Walleij wrote:
> On Mon, Nov 25, 2013 at 4:41 PM, Matthew Garrett <mjg59@srcf.ucam.org> wrote:
>
> > In the past ACPI implementations handled GPIO by providing
> > methods that accessed hardware registers directly. I've seen DSDTs that
> > implement i2c entirely in ASL.
>
> Is that common?
No, thankfully.
> Since i2c is a slow bus, can be 100kHz or so, how does that
> avoid locking the entire CPU while e.g. waiting for transactions on
> the external bus to complete?
Check status register, interruptible sleep, repeat until done.
> I have a feeling we should not recommend ARM implementers
> to go and do things like this.
Oh, absolutely.
--
Matthew Garrett | mjg59 at srcf.ucam.org
prev parent reply other threads:[~2013-11-26 14:45 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-11-18 18:42 ACPI Jon Masters
[not found] ` < CACRpkdY+6dzs8MpKKtW-3kzsLkZjsit9SeN20k_33TAtVf3NEA@mail.gmail.com>
[not found] ` < CACxGe6t_9hUXL_1PHRU=2DYOYfCqZykd7gYRCshZn0XsVoCdRw@mail.gmail.com>
[not found] ` < 20131126183344.GA16074@srcf.ucam.org>
[not found] ` < CACRpkdbNxxNK0GM28H_nDLu6EpbQ-EYAdEeTp5fnXW5mkEPkgw@mail.gmail.com>
[not found] ` < CACxGe6uHuWPh7d9NaVuPRBWq0Fh1BmDV190KEN4C4uaq4KjS8g@mail.gmail.com>
[not found] ` < CACRpkdaCXJzWXoesjD3Jqpm4XMHLQp3SsHcsDG3veUS+xarqHQ@mail.gmail.com>
[not found] ` < CACxGe6vUKzow7QpeX2mU7CiZQzY8aZ+p0jd8Vk0+dqz0B=D0Ew@mail.gmail.com>
2013-11-19 18:15 ` ACPI Arnd Bergmann
2013-11-21 20:03 ` ACPI Mark Brown
2013-11-22 0:29 ` ACPI Arnd Bergmann
2013-11-22 4:05 ` ACPI Jon Masters
2013-11-22 20:31 ` ACPI Arnd Bergmann
2013-11-22 20:59 ` ACPI Jon Masters
2013-11-22 21:37 ` ACPI Jon Masters
2013-11-23 9:11 ` ACPI Arnd Bergmann
2013-11-23 18:39 ` ACPI Jason Gunthorpe
2013-11-23 23:03 ` ACPI Matthew Garrett
2013-11-24 3:52 ` ACPI Jon Masters
2013-11-24 3:56 ` ACPI Matthew Garrett
2013-11-24 23:21 ` ACPI Jon Masters
2013-11-24 23:40 ` ACPI Matthew Garrett
2013-11-22 13:19 ` ACPI Mark Brown
2013-11-19 18:28 ` ACPI Måns Rullgård
2013-11-21 16:56 ` ACPI Matthew Garrett
2013-11-24 17:14 ` ACPI Linus Walleij
2013-11-25 0:42 ` ACPI Grant Likely
2013-11-25 1:28 ` ACPI Matthew Garrett
2013-11-25 11:07 ` ACPI Linus Walleij
2013-11-25 11:33 ` ACPI Grant Likely
2013-11-25 15:41 ` ACPI Matthew Garrett
2013-11-26 12:43 ` ACPI Linus Walleij
2013-11-26 12:55 ` ACPI Grant Likely
2013-11-26 13:43 ` ACPI Jürgen Beisert
2013-11-27 12:25 ` ACPI Grant Likely
2013-11-28 13:16 ` ACPI Linus Walleij
2013-11-26 18:33 ` ACPI Matthew Garrett
2013-11-26 23:11 ` ACPI Matt Sealey
2013-11-26 23:32 ` ACPI Matthew Garrett
2013-11-27 11:00 ` ACPI Catalin Marinas
2013-11-27 22:12 ` ACPI Nicolas Pitre
2013-11-27 20:21 ` ACPI Matt Sealey
2013-11-28 6:21 ` ACPI Jon Masters
2013-11-28 18:26 ` ACPI Stefano Stabellini
2013-11-28 18:48 ` ACPI Matthew Garrett
2013-11-28 18:51 ` ACPI Stefano Stabellini
2013-11-27 14:16 ` ACPI Grant Likely
2013-11-27 22:17 ` ACPI Matt Sealey
2013-11-28 13:50 ` ACPI Leif Lindholm
2013-11-28 15:43 ` ACPI Grant Likely
2013-11-27 12:41 ` ACPI Grant Likely
2013-11-26 14:45 ` Matthew Garrett [this message]
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