diff mbox

[v2,2/5] Documentation: Detail permitted DT properties for the imx6ul_tsc

Message ID 1438077521-12857-3-git-send-email-haibo.chen@freescale.com (mailing list archive)
State New, archived
Headers show

Commit Message

Haibo Chen July 28, 2015, 9:58 a.m. UTC 
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 <haibo.chen@freescale.com>
---
 .../bindings/input/touchscreen/imx6ul_tsc.txt      | 36 ++++++++++++++++++++++
 1 file changed, 36 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/input/touchscreen/imx6ul_tsc.txt

Comments

Markus Pargmann Aug. 19, 2015, 5:54 a.m. UTC | #1 
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 <haibo.chen@freescale.com>
> ---
>  .../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.txt
> @@ -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.

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
> 
> 
>
Markus Pargmann Aug. 21, 2015, 9:27 a.m. UTC | #2 
On Fri, Aug 21, 2015 at 08:30:16AM +0000, Chen Bough wrote:
> Hi Markus,
> 
> > -----Original Message-----
> > From: Markus Pargmann [mailto:mpa@pengutronix.de]
> > Sent: Wednesday, August 19, 2015 1:55 PM
> > To: Chen Haibo-B51421
> > Cc: robh+dt@kernel.org; pawel.moll@arm.com; mark.rutland@arm.com;
> > ijc+devicetree@hellion.org.uk; galak@codeaurora.org; shawnguo@kernel.org;
> > kernel@pengutronix.de; linux@arm.linux.org.uk; dmitry.torokhov@gmail.com;
> > devicetree@vger.kernel.org; sbranden@broadcom.com; arnd@arndb.de;
> > mchehab@osg.samsung.com; christian.gmeiner@gmail.com;
> > scott.liu@emc.com.tw; linux-kernel@vger.kernel.org; hdegoede@redhat.com;
> > jonathar@broadcom.com; benjamin.tissoires@redhat.com;
> > hans.verkuil@cisco.com; hadess@hadess.net; linux-input@vger.kernel.org;
> > geert@linux-m68k.org; sebastien.szymanski@armadeus.com;
> > mamlinav@gmail.com; linux-arm-kernel@lists.infradead.org
> > 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 <haibo.chen@freescale.com>
> > > ---
> > >  .../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
> > |
diff mbox

Patch

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.txt
@@ -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.
+- 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";
+	};