Re: [RESEND PATCH v5 00/16] eeprom: at24: Add OF device ID table

From: Javier Martinez Canillas <javier@dowhile0.org>
To: Wolfram Sang <wsa@the-dreams.de>
Cc: "Linux Kernel" <linux-kernel@vger.kernel.org>,
	"Rob Herring" <robh@kernel.org>, "Florian Larysch" <fl@n621.de>,
	"David Lechner" <david@lechnology.com>,
	"Rob Herring" <robh+dt@kernel.org>,
	"Andy Shevchenko" <andy.shevchenko@gmail.com>,
	"Catalin Marinas" <catalin.marinas@arm.com>,
	"Sören Brinkmann" <soren.brinkmann@xilinx.com>,
	"Simon Horman" <horms@verge.net.au>,
	"Michal Simek" <michal.simek@xilinx.com>,
	"Dinh Nguyen" <dinguyen@kernel.org>,
	"Russell King" <linux@armlinux.org.uk>,
	"Will Deacon" <will.deacon@arm.com>,
	"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
	"Sekhar Nori" <nsekhar@ti.com>, "Scott Wood" <oss@buserror.net>,
	"Benjamin Herrenschmidt" <benh@kernel.crashing.org>,
	"Joachim Eastwood" <manabian@gmail.com>,
	"Mark Rutland" <mark.rutland@arm.com>,
	"linux-arm-kernel@lists.infradead.org"
	<linux-arm-kernel@lists.infradead.org>,
	"Masahiro Yamada" <yamada.masahiro@socionext.com>,
	"Michael Ellerman" <mpe@ellerman.id.au>,
	"Santosh Shilimkar" <ssantosh@kernel.org>,
	Linux-Renesas <linux-renesas-soc@vger.kernel.org>,
	"Paul Mackerras" <paulus@samba.org>,
	"Magnus Damm" <magnus.damm@gmail.com>,
	linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
	"Uwe Kleine-König" <kernel@pengutronix.de>,
	"Linux I2C" <linux-i2c@vger.kernel.org>
Subject: Re: [RESEND PATCH v5 00/16] eeprom: at24: Add OF device ID table
Date: Wed, 30 Aug 2017 18:19:02 +0200	[thread overview]
Message-ID: <CABxcv=nqbNsTs7D57VOt1-Tav_3i9U=XKn=BV=hPr1tG68eE2g@mail.gmail.com> (raw)
In-Reply-To: <20170829084831.hsdok3ksi7anxzuc@ninjato>

Hello Wolfram,

On Tue, Aug 29, 2017 at 10:48 AM, Wolfram Sang <wsa@the-dreams.de> wrote:
>
>> I don't have a DT based system at hand now, but I'll test it again and
>> let you know probably tomorrow.
>
> I will try again today, too. Thanks!
>

Ok, I had some time to do some tests again. I used an ARM Chromebook
(Exynos Peach Pi) that has an I2C touchpad (Atmel maXTouch).

Tested the following cases:

1) Driver without OF device ID table (only a I2C table with a
"maxtouch" entry) and DTS defining a device node with a
"atmel,maxtouch" compatible string. This is the case without any of
the patches in this series.

$ modinfo drivers/input/touchscreen/atmel_mxt_ts.ko | grep maxtouch
alias:          i2c:maxtouch

$ grep maxtouch /sys/devices/platform/soc/12e00000.i2c/i2c-8/8-004b/uevent
OF_COMPATIBLE_0=atmel,maxtouch
MODALIAS=i2c:maxtouch

2) Driver without OF device ID table (only a I2C table with a
"maxtouch" entry) and DTS defining a device node with a
"atmel,maxtouch", "generic,maxtouch" compatible string. This is the
case when platform maintainers merge the DTS patches without the
driver patch.

$ modinfo drivers/input/touchscreen/atmel_mxt_ts.ko | grep maxtouch
alias:          i2c:maxtouch

$ grep maxtouch /sys/devices/platform/soc/12e00000.i2c/i2c-8/8-004b/uevent
OF_COMPATIBLE_0=atmel,maxtouch
OF_COMPATIBLE_1=generic,maxtouch
MODALIAS=i2c:maxtouch

3) Driver with an OF device ID table (with a "generic,maxtouch" entry)
and DTS defining a device node with a "atmel,maxtouch" compatible
string. This is the case when the driver patch is merged without the
DTS patches.

$ modinfo drivers/input/touchscreen/atmel_mxt_ts.ko | grep maxtouch
alias:          of:N*T*Cgeneric,maxtouchC*
alias:          of:N*T*Cgeneric,maxtouch
alias:          i2c:maxtouch

$ grep maxtouch /sys/devices/platform/soc/12e00000.i2c/i2c-8/8-004b/uevent
OF_COMPATIBLE_0=atmel,maxtouch
MODALIAS=i2c:maxtouch

4) Driver with an OF device ID table (with a "generic,maxtouch" entry)
and DTS defining a device node with a "atmel,maxtouch",
"generic,maxtouch" compatible string. This is the case when both the
DTS and driver patches are merged.

$ modinfo drivers/input/touchscreen/atmel_mxt_ts.ko | grep maxtouch
alias:          of:N*T*Cgeneric,maxtouchC*
alias:          of:N*T*Cgeneric,maxtouch
alias:          i2c:maxtouch

$ grep maxtouch /sys/devices/platform/soc/12e00000.i2c/i2c-8/8-004b/uevent
OF_COMPATIBLE_0=atmel,maxtouch
OF_COMPATIBLE_1=generic,maxtouch
MODALIAS=i2c:maxtouch

For all cases module autoload, driver probe and evtest worked for me.

You said that (3) doesn't work but I don't understand why is failing
for you. Probably I'm missing something.

Best regards,
Javier