On Fri, Aug 21, 2015 at 08:30:16AM +0000, Chen Bough wrote: > Hi Markus, > > > -----Original Message----- > > From: Markus Pargmann [mailto:[email protected]] > > Sent: Wednesday, August 19, 2015 1:55 PM > > To: Chen Haibo-B51421 > > Cc: [email protected]; [email protected]; [email protected]; > > [email protected]; [email protected]; [email protected]; > > [email protected]; [email protected]; [email protected]; > > [email protected]; [email protected]; [email protected]; > > [email protected]; [email protected]; > > [email protected]; [email protected]; [email protected]; > > [email protected]; [email protected]; > > [email protected]; [email protected]; [email protected]; > > [email protected]; [email protected]; > > [email protected]; [email protected] > > Subject: Re: [PATCH v2 2/5] Documentation: Detail permitted DT properties > > for the imx6ul_tsc > > > > Hi, > > > > On Tue, Jul 28, 2015 at 05:58:38PM +0800, Haibo Chen wrote: > > > Here we apply required documentation for the imx6ul touch screen > > > controller driver which describe available properties and how to use > > > them. > > > > > > Signed-off-by: Haibo Chen <[email protected]> > > > --- > > > .../bindings/input/touchscreen/imx6ul_tsc.txt | 36 > > ++++++++++++++++++++++ > > > 1 file changed, 36 insertions(+) > > > create mode 100644 > > > Documentation/devicetree/bindings/input/touchscreen/imx6ul_tsc.txt > > > > > > diff --git > > > a/Documentation/devicetree/bindings/input/touchscreen/imx6ul_tsc.txt > > > b/Documentation/devicetree/bindings/input/touchscreen/imx6ul_tsc.txt > > > new file mode 100644 > > > index 0000000..ac41c32 > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/input/touchscreen/imx6ul_tsc.t > > > +++ xt > > > @@ -0,0 +1,36 @@ > > > +* Freescale i.MX6UL Touch Controller > > > + > > > +Required properties: > > > +- compatible: must be "fsl,imx6ul-tsc". > > > +- reg: this touch controller address and the ADC2 address. > > > > This suggests that this driver is using a unit ADC2. Which also means > > that there are more than one ADC which are probably identical? > > > > Shouldn't these ADCs be properly described by their own device nodes > > instead of these two register ranges, two interrupts and two clocks? > > > > Is 'ADC2' usable without tsc? Then ADC1/ADC2 should perhaps get a proper > > IIO driver. > > For i.MX6UL, there are two ADC. ADC1 is a normal ADC, and ADC2 can only works > for > TSC, the channels of ADC2 are connected to TSC directly. TSC and ADC2 should > work > together as a touch screen controller.
But as I understand these are two different units. Wouldn't it be better
to abstract it that way in the DT?
Best regards,
Markus
>
> For ADC1, it share the driver vf610_adc.c (drivers/iio/adc/vf610_adc.c).
>
> Best Regards
>
> Haibo
>
> >
> > Unfortunately I don't have the reference manual to have a look how this
> > all works.
> >
> > Best regards,
> >
> > Markus
> >
> > > +- interrupts: the interrupt of this touch controller and ADC2.
> > > +- clocks: the root clock of touch controller and ADC2.
> > > +- clock-names; must be "tsc" and "adc".
> > > +- xnur-gpio: the X- gpio this controller connect to.
> > > + This xnur-gpio returns to high once the finger leave the touch
> > > +screen (The
> > > + last touch event the touch controller capture).
> > > +
> > > +Optional properties:
> > > +- measure-delay-time: the value of measure delay time.
> > > + Before X-axis or Y-axis measurement, the screen need some time
> > > +before
> > > + even potential distribution ready.
> > > + This value depends on the touch screen.
> > > +- pre-charge-time: the touch screen need some time to precharge.
> > > + This value depends on the touch screen.
> > > +
> > > +Example:
> > > + tsc: tsc@02040000 {
> > > + compatible = "fsl,imx6ul-tsc";
> > > + reg = <0x02040000 0x4000>, <0x0219c000 0x4000>;
> > > + interrupts = <GIC_SPI 3 IRQ_TYPE_LEVEL_HIGH>,
> > > + <GIC_SPI 101 IRQ_TYPE_LEVEL_HIGH>;
> > > + clocks = <&clks IMX6UL_CLK_IPG>,
> > > + <&clks IMX6UL_CLK_ADC2>;
> > > + clock-names = "tsc", "adc";
> > > + pinctrl-names = "default";
> > > + pinctrl-0 = <&pinctrl_tsc>;
> > > + xnur-gpio = <&gpio1 3 GPIO_ACTIVE_HIGH>;
> > > + measure-delay-time = <0xfff>;
> > > + pre-charge-time = <0xffff>;
> > > + status = "okay";
> > > + };
> > > --
> > > 1.9.1
> > >
> > >
> > >
> >
> > --
> > Pengutronix e.K. |
> > |
> > Industrial Linux Solutions | http://www.pengutronix.de/
> > |
> > Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0
> > |
> > Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555
> > |
--
Pengutronix e.K. | |
Industrial Linux Solutions | http://www.pengutronix.de/ |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
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