All of lore.kernel.org
 help / color / mirror / Atom feed
From: Wolfram Sang <wsa@the-dreams.de>
To: Guenter Roeck <linux@roeck-us.net>
Cc: linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] eeprom: at24: Add support for large EEPROMs connected to SMBus adapters
Date: Wed, 4 Feb 2015 18:47:23 +0100	[thread overview]
Message-ID: <20150204174723.GB30930@katana> (raw)
In-Reply-To: <1423067017-27607-1-git-send-email-linux@roeck-us.net>

[-- Attachment #1: Type: text/plain, Size: 823 bytes --]


On Wed, Feb 04, 2015 at 08:23:37AM -0800, Guenter Roeck wrote:
> Large EEPROMS (24c32 and larger) require a two-byte data address
> instead of just a single byte. Implement support for such EEPROMs
> with SMBus commands.
> 
> Support has limitations (reads are not multi-master safe) and is slow,
> but it works. Practical use is for a system with 24c32 connected to
> Intel 82801I (ICH9).

Can't you simply use i2c-dev to access the EEPROM? In multi-master
environments, things can really go wrong, so I wouldn't like to add
something dangerous by default. Maybe with a module parameter named
"allow-multimaster-unsafe-access-to-large-eeproms-with-smbus" which is
default off. But I'd really prefer the i2c-dev solution. Hooking a 16bit
EEPROM to SMBus is daring, after all. SMBus is multi-master, too.


[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 819 bytes --]

  reply	other threads:[~2015-02-04 17:47 UTC|newest]

Thread overview: 38+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-02-04 16:23 [PATCH] eeprom: at24: Add support for large EEPROMs connected to SMBus adapters Guenter Roeck
2015-02-04 16:23 ` Guenter Roeck
2015-02-04 17:47 ` Wolfram Sang [this message]
2015-02-04 19:08   ` Guenter Roeck
2015-02-04 19:08     ` Guenter Roeck
2015-02-04 23:35     ` Wolfram Sang
2015-02-05  0:26       ` Guenter Roeck
2015-02-05  0:26         ` Guenter Roeck
2015-02-05 14:40         ` Wolfram Sang
2015-02-05 17:53           ` Guenter Roeck
2015-02-12  4:01             ` Guenter Roeck
2015-02-12  4:01               ` Guenter Roeck
2015-02-16 12:09               ` Wolfram Sang
2015-02-16 15:37                 ` Guenter Roeck
2015-03-17  4:20                 ` Guenter Roeck
2015-03-17  4:20                   ` Guenter Roeck
2015-03-18 13:27                   ` Wolfram Sang
2015-03-19  3:24                     ` Guenter Roeck
2015-03-19  8:16                       ` Wolfram Sang
2015-03-19  8:16                         ` Wolfram Sang
2015-03-19 13:30                         ` Guenter Roeck
2015-03-19 13:30                           ` Guenter Roeck
2015-03-19 17:43                         ` Guenter Roeck
2015-03-19 17:43                           ` Guenter Roeck
2015-03-19 21:39                           ` Wolfram Sang
2015-03-25 14:11                             ` Guenter Roeck
2015-03-25 16:15                               ` Wolfram Sang
2015-03-25 16:15                                 ` Wolfram Sang
2015-03-25 16:37                                 ` Guenter Roeck
2015-03-25 16:37                                   ` Guenter Roeck
2015-03-27  8:09                               ` Wolfram Sang
2015-03-27 12:51                                 ` Guenter Roeck
2015-03-27 13:01                                   ` Wolfram Sang
2015-03-27 13:14                                     ` Guenter Roeck
2015-03-27 15:27                                       ` Wolfram Sang
2015-03-27 15:42                                         ` Guenter Roeck
2015-03-27 15:42                                           ` Guenter Roeck
2015-02-04 20:33   ` Guenter Roeck

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=20150204174723.GB30930@katana \
    --to=wsa@the-dreams.de \
    --cc=linux-i2c@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux@roeck-us.net \
    /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.