From: s.nawrocki@samsung•com (Sylwester Nawrocki)
To: linux-arm-kernel@lists•infradead.org
Subject: [RFC PATCH 5/7] ARM: davinci: i2c: add OF support
Date: Tue, 24 Jan 2012 10:51:50 +0100 [thread overview]
Message-ID: <4F1E7F36.50505@samsung.com> (raw)
In-Reply-To: <4F1E5B44.4090200@denx.de>
Hello Heiko,
On 01/24/2012 08:18 AM, Heiko Schocher wrote:
>> On 01/23/2012 09:56 AM, Heiko Schocher wrote:
>>> add of support for the davinci i2c driver.
>>>
>>> Signed-off-by: Heiko Schocher<hs@denx•de>
>>> Cc: davinci-linux-open-source at linux.davincidsp.com
>>> Cc: linux-arm-kernel at lists.infradead.org
>>> Cc: devicetree-discuss at lists.ozlabs.org
>>> Cc: linux-i2c at vger.kernel.org
>>> Cc: Ben Dooks<ben-linux@fluff•org>
>>> Cc: Wolfram Sang<w.sang@pengutronix•de>
>>> Cc: Grant Likely<grant.likely@secretlab•ca>
>>> Cc: Sekhar Nori<nsekhar@ti•com>
>>> Cc: Wolfgang Denk<wd@denx•de>
>>> ---
>>> .../devicetree/bindings/arm/davinci/i2c.txt | 39 ++++++++++++++++++
>>> drivers/i2c/busses/i2c-davinci.c | 43 ++++++++++++++++++++
>>> 2 files changed, 82 insertions(+), 0 deletions(-)
>>> create mode 100644 Documentation/devicetree/bindings/arm/davinci/i2c.txt
>>>
>>> diff --git a/Documentation/devicetree/bindings/arm/davinci/i2c.txt b/Documentation/devicetree/bindings/arm/davinci/i2c.txt
>>> new file mode 100644
>>> index 0000000..94ec670
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/arm/davinci/i2c.txt
>>> @@ -0,0 +1,39 @@
>>> +* Texas Instruments Davinci I2C
>>> +
>>> +This file provides information, what the device node for the
>>> +davinci i2c interface contain.
>>> +
>>> +Required properties:
>>> +- compatible: "ti,davinci-i2c";
>>> +- reg : Offset and length of the register set for the device
>>> +- id: id of the controller
>>
>> I was wondering whether we're supposed to use "cell-index" property name
>> for such a device instance index? or doesn't it really matter and "id" is
>> fine? Such an IP instance index seems quite common so I thought it could
>> be easier to follow to use standard name.
>
> I just copied the "name" from "struct davinci_nand_pdata" ... it is
> used in the davinci_nand driver as chipselect ... maybe it is better
> I rename this to "chipselect" ?
>From what I can see the 'id' property is used to determine I2C adapter
number. In that case 'id' seems more correct than "chipselect". Are you
sure there is a chip select functionality in I2C controller ?
It seems that your id is just an index of I2C controller in hardware.
I would personally just use cell-index for that, but I'm not a dt expert,
someone nay correct me.
For instance, this is how "cell-index" semantics is described in case
of MPC5200 Programmable Serial Controllers (from Documentation/devicetree/
bindings/powerpc/fsl/mpc5200.txt):
"fsl,mpc5200-psc nodes
---------------------
The PSCs should include a cell-index which is the index of the PSC in
hardware. cell-index is used to determine which shared SoC registers to
use when setting up PSC clocking. cell-index number starts at '0'. ie:
PSC1 has 'cell-index = <0>'
PSC4 has 'cell-index = <3>'"
Moreover you seem to overwrite platform device name and id,
if (!of_property_read_u32(pdev->dev.of_node, "id",
+ &prop)) {
+ pdev->id = prop;
+ pdev->dev.init_name = kzalloc(20, GFP_KERNEL);
+ sprintf((char *)pdev->dev.init_name,
+ "i2c_davinci.%d", pdev->id);
I'm not sure if it is a good practice. If you want to pre-define platform
device name (likely for the clock API to work), it might be more appropriate
to use OF_DEV_AUXDATA in the machine code, until there are clock bindings
available.
Then you would just use your 'id'/'cell-index' property to set an I2C adapter
number.
--
Regards,
Sylwester
next prev parent reply other threads:[~2012-01-24 9:51 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-01-23 8:56 [RFC PATCH 0/7] ARM: davinci: add support for the am1808 based enbw_cmc board Heiko Schocher
2012-01-23 8:56 ` [RFC PATCH 1/7] ARM: davinci, intc: Add OF support for TI interrupt controller Heiko Schocher
2012-02-02 4:54 ` Grant Likely
2012-02-06 6:36 ` Heiko Schocher
2012-02-14 7:15 ` Heiko Schocher
2012-01-23 8:56 ` [RFC PATCH 2/7 v2] ARM: davinci: configure davinci aemif chipselects through OF Heiko Schocher
2012-01-23 8:56 ` [RFC PATCH 3/7] ARM: davinci: mux: add OF support Heiko Schocher
2012-01-23 8:56 ` [RFC PATCH 4/7] ARM: davinci: net: davinci_emac: " Heiko Schocher
2012-01-23 19:20 ` Anatoly Sivov
2012-01-24 6:14 ` Heiko Schocher
2012-01-30 20:22 ` Grant Likely
2012-01-31 11:27 ` Heiko Schocher
2012-02-02 0:19 ` Grant Likely
2012-01-23 8:56 ` [RFC PATCH 5/7] ARM: davinci: i2c: " Heiko Schocher
2012-01-23 20:35 ` Sylwester Nawrocki
2012-01-24 7:18 ` Heiko Schocher
2012-01-24 9:51 ` Sylwester Nawrocki [this message]
2012-01-30 20:13 ` Grant Likely
2012-01-31 7:31 ` Heiko Schocher
2012-02-05 20:44 ` Sylwester Nawrocki
2012-01-30 20:04 ` Grant Likely
2012-01-31 7:14 ` Heiko Schocher
2012-02-13 23:37 ` Ben Dooks
2012-02-14 7:16 ` Heiko Schocher
2012-01-23 8:56 ` [RFC PATCH 6/7] ARM: mtd: nand: davinci: add OF support for davinci nand controller Heiko Schocher
2012-01-23 23:59 ` Scott Wood
2012-01-24 7:23 ` Heiko Schocher
2012-01-24 19:45 ` Scott Wood
2012-01-25 7:09 ` Heiko Schocher
2012-01-26 20:33 ` Scott Wood
2012-01-27 6:40 ` Heiko Schocher
2012-01-27 17:02 ` Scott Wood
2012-01-23 8:56 ` [RFC PATCH 7/7] ARM: davinci: add support for the am1808 based enbw_cmc board Heiko Schocher
2012-01-30 20:32 ` Grant Likely
2012-01-31 13:04 ` Heiko Schocher
2012-02-01 10:20 ` Sergei Shtylyov
2012-02-02 0:17 ` Grant Likely
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=4F1E7F36.50505@samsung.com \
--to=s.nawrocki@samsung$(echo .)com \
--cc=linux-arm-kernel@lists$(echo .)infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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