linux-i2c.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Sam Hansen <hansens@google.com>
To: linux-i2c@vger.kernel.org
Cc: Sam Hansen <hansens@google.com>,
	wsa@the-dreams.de, corbet@lwn.net, linux-doc@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH v3 2/3] Documentation/i2c: sync docs with current state of i2c-tools
Date: Fri, 13 Apr 2018 10:42:56 -0700	[thread overview]
Message-ID: <20180413174257.139182-2-hansens@google.com> (raw)
In-Reply-To: <20180413174257.139182-1-hansens@google.com>

Currently, Documentation/i2c/dev-interface describes the use of
i2c_smbus_* helper routines as static inlined functions provided by
linux/i2c-dev.h.  Work has been done to refactor the linux/i2c-dev.h file
in the i2c-tools project out into its own library.  As a result, these
docs have become stale.

This patch corrects the discrepancy and directs the reader to the
i2c-tools project for more information.

Signed-off-by: Sam Hansen <hansens@google.com>
---
No changes from v2.

 Documentation/i2c/dev-interface | 16 +++++-----------
 1 file changed, 5 insertions(+), 11 deletions(-)

diff --git a/Documentation/i2c/dev-interface b/Documentation/i2c/dev-interface
index c8737d502791..f92ee1f59914 100644
--- a/Documentation/i2c/dev-interface
+++ b/Documentation/i2c/dev-interface
@@ -23,11 +23,6 @@ First, you need to include these two headers:
   #include <linux/i2c-dev.h>
   #include <i2c/smbus.h>
 
-(Please note that there are two files named "i2c-dev.h" out there. One is
-distributed with the Linux kernel and the other one is included in the
-source tree of i2c-tools. They used to be different in content but since 2012
-they're identical. You should use "linux/i2c-dev.h").
-
 Now, you have to decide which adapter you want to access. You should
 inspect /sys/class/i2c-dev/ or run "i2cdetect -l" to decide this.
 Adapter numbers are assigned somewhat dynamically, so you can not
@@ -140,8 +135,8 @@ ioctl(file, I2C_RDWR, struct i2c_rdwr_ioctl_data *msgset)
   set in each message, overriding the values set with the above ioctl's.
 
 ioctl(file, I2C_SMBUS, struct i2c_smbus_ioctl_data *args)
-  Not meant to be called  directly; instead, use the access functions
-  below.
+  If possible, use the provided i2c_smbus_* methods described below instead
+  of issuing direct ioctls.
 
 You can do plain i2c transactions by using read(2) and write(2) calls.
 You do not need to pass the address byte; instead, set it through
@@ -166,10 +161,9 @@ what happened. The 'write' transactions return 0 on success; the
 returns the number of values read. The block buffers need not be longer
 than 32 bytes.
 
-The above functions are all inline functions, that resolve to calls to
-the i2c_smbus_access function, that on its turn calls a specific ioctl
-with the data in a specific format. Read the source code if you
-want to know what happens behind the screens.
+The above functions are made available by linking against the libi2c library,
+which is provided by the i2c-tools project.  See:
+https://git.kernel.org/pub/scm/utils/i2c-tools/i2c-tools.git/.
 
 
 Implementation details
-- 
2.17.0.484.g0c8726318c-goog

  reply	other threads:[~2018-04-13 17:42 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-04-13 17:42 [PATCH v3 1/3] Documentation/i2c: whitespace cleanup Sam Hansen
2018-04-13 17:42 ` Sam Hansen [this message]
2018-04-18  8:09   ` [PATCH v3 2/3] Documentation/i2c: sync docs with current state of i2c-tools Wolfram Sang
2018-04-18  8:21   ` Wolfram Sang
2018-04-18 18:17     ` Sam Hansen
2018-04-13 17:42 ` [PATCH v3 3/3] Documentation/i2c: adopt kernel commenting style in examples Sam Hansen
2018-04-18  8:10   ` Wolfram Sang
2018-04-18  8:08 ` [PATCH v3 1/3] Documentation/i2c: whitespace cleanup Wolfram Sang

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=20180413174257.139182-2-hansens@google.com \
    --to=hansens@google.com \
    --cc=corbet@lwn.net \
    --cc=linux-doc@vger.kernel.org \
    --cc=linux-i2c@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=wsa@the-dreams.de \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).