Re: [RFC PATCH] mfd: pm8x41: Naive function devices registration

From: "Ivan T. Ivanov" <iivanov@mm-sol.com>
To: Rob Herring <robherring2@gmail.com>
Cc: Courtney Cavin <courtney.cavin@sonymobile.com>,
	Josh Cartwright <joshc@codeaurora.org>,
	Samuel Ortiz <sameo@linux.intel.com>,
	Lee Jones <lee.jones@linaro.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	linux-arm-msm <linux-arm-msm@vger.kernel.org>
Subject: Re: [RFC PATCH] mfd: pm8x41: Naive function devices registration
Date: Fri, 25 Apr 2014 16:29:01 +0300	[thread overview]
Message-ID: <1398432541.4724.243.camel@iivanov-dev> (raw)
In-Reply-To: <CAL_JsqJMs1ULgLMAia6ojz+i3b=7W6hxyqSTMATo96i0cS2n0g@mail.gmail.com>

On Fri, 2014-04-25 at 08:00 -0500, Rob Herring wrote:
> On Fri, Apr 25, 2014 at 7:32 AM, Ivan T. Ivanov <iivanov@mm-sol.com> wrote:
> > From: "Ivan T. Ivanov" <iivanov@mm-sol.com>
> >
> > Currently functions that exist in both the controller at the
> > same address offset can not be specified with the same names.
> >
> > Adding Unique Slave ID device address to prefix function
> > device names fixes this.
> >
> > Function devices are SPMI devices, so register them on
> > SPMI bus.
> >
> > Signed-off-by: Ivan T. Ivanov <iivanov@mm-sol.com>
> > ---
> >  drivers/mfd/pm8x41.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++++----
> 
> No, this should be fixed in the core, not the driver.

I think that at core level they are no issues. 
There is no name clashes with "top level" devices.

spmi@...{
	...
	child@0 {
	        compatible = "qcom,pm8941";
	        reg = <0x0 SPMI_USID>;

	        #address-cells = <1>;
	        #size-cells = <0>;

	        revid@100 {
	                compatible = "qcom,qpnp-revid";
	                reg = <0x100>;
	        };
	};

	child@4 {
	        compatible = "qcom,pm8841";
	        reg = <0x4 SPMI_USID>;

	        #address-cells = <1>;
	        #size-cells = <0>;

	        revid@100 {
	                compatible = "qcom,qpnp-revid";
	                reg = <0x100>;
	        };
	};
};

I don't have experience with SPMI devices, but it looks
like address partitioning is specific to this "PMIC"
controllers.

Regards,
Ivan

> 
> Rob