From mboxrd@z Thu Jan  1 00:00:00 1970
From: paul.liu@linaro.org (Ying-Chun Liu (PaulLiu))
Date: Thu, 01 Mar 2012 17:19:47 +0800
Subject: [PATCH v4 1/2] mfd: Add anatop mfd driver
In-Reply-To: <20120221111705.GV5387@sortiz-mobl>
References: <1324980994-18462-1-git-send-email-paul.liu@linaro.org>
 <1328734286-30091-1-git-send-email-paul.liu@linaro.org>
 <20120221111705.GV5387@sortiz-mobl>
Message-ID: <4F4F3F33.4000608@linaro.org>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

(2012?02?21? 19:17), Samuel Ortiz wrote:
> Hi Paul,
> 
> I didn't get patch #2, so I don't get to see how the read/write functions ar
> eused for example.
> 

Hi Samuel,

Sorry for late reply.
I've sent out v5 today.

>> +	ioreg = ioremap(ofaddr, ofsize);
>> +	if (!ioreg)
>> +		return -EINVAL;
>> +	drvdata = devm_kzalloc(dev, sizeof(struct anatop), GFP_KERNEL);
>> +	if (!drvdata)
>> +		return -EINVAL;
>> +	drvdata->ioreg = ioreg;
>> +	drvdata->read = anatop_read;
>> +	drvdata->write = anatop_write;
>> +	platform_set_drvdata(pdev, drvdata);
>> +	of_platform_bus_probe(np, of_anatop_regulator_match, dev);
>> +	return ret;
>> +}
> So it seems that your driver here does nothing but extending your device tree
> definition. Correct me if I'm wrong, aren't you trying to fix a broken device
> tree definition here ?
> 

The driver here ioremap the addresses for anatop chip in i.MX6Q SoC. The
addresses are shared by several regulators. Also thermal drivers are
also in the same range.

Here are examples of the anatop description in dts file

   anatop at 020c8000 {
           compatible = "fsl,imx6q-anatop";
           reg = <0x020c8000 0x1000>;
           interrupts = <0 49 0x04 0 54 0x04 0 127 0x04>;
           #address-cells = <1>;
           #size-cells = <1>;
           reg_vddpu: regulator-vddpu at 140 {
                   compatible = "fsl,anatop-regulator";
                   regulator-name = "vddpu";
                   regulator-min-microvolt = <725000>;
                   regulator-max-microvolt = <1300000>;
                   regulator-always-on;
                   reg = <0x140 1>;
                   vol-bit-shift = <9>;
                   vol-bit-size = <5>;
                   min-bit-val = <1>;
                   min-voltage = <725000>;
                   max-voltage = <1300000>;
           };
           reg_vddcore: regulator-vddcore at 140 {
                   compatible = "fsl,anatop-regulator";
                   regulator-name = "vddcore";
                   regulator-min-microvolt = <725000>;
                   regulator-max-microvolt = <1300000>;
                   regulator-always-on;
                   reg = <0x140 1>;
                   vol-bit-shift = <0>;
                   vol-bit-size = <5>;
                   min-bit-val = <1>;
                   min-voltage = <725000>;
                   max-voltage = <1300000>;
           };
           ...

So both reg_vddpu and reg_vddcore are using the same address.

Yours Sincerely,
Paul