[PATCH 1/2] ARM: dts: sun5i: Add touchscreen node to reference-design-tablet.dtsi

Thu Nov 17 10:52:38 PST 2016

Hi,

On 17-11-16 19:35, Maxime Ripard wrote:
> Hi Hans,
>
> On Tue, Nov 15, 2016 at 11:12:35AM +0100, Hans de Goede wrote:
>> Hi,
>>
>> On 14-11-16 21:08, Maxime Ripard wrote:
>>> Hi,
>>>
>>> On Sun, Nov 13, 2016 at 08:22:02PM +0100, Hans de Goede wrote:
>>>> Just like on sun8i all sun5i tablets use the same interrupt and power
>>>> gpios for their touchscreens. I've checked all known a13 fex files and
>>>> only the UTOO P66 uses a different gpio for the interrupt.
>>>>
>>>> Add a touchscreen node to sun5i-reference-design-tablet.dtsi, which
>>>> fills in the necessary gpios to avoid duplication in the tablet dts files,
>>>> just like we do in sun8i-reference-design-tablet.dtsi.
>>>>
>>>> This will make future patches adding touchscreen nodes to a13 tablets
>>>> simpler.
>>>>
>>>> Signed-off-by: Hans de Goede <hdegoede at redhat.com>
>>>> ---
>>>>  arch/arm/boot/dts/sun5i-a13-utoo-p66.dts           | 38 ++++++++--------------
>>>>  .../boot/dts/sun5i-reference-design-tablet.dtsi    | 25 ++++++++++++++
>>>>  2 files changed, 39 insertions(+), 24 deletions(-)
>>>>
>>>> diff --git a/arch/arm/boot/dts/sun5i-a13-utoo-p66.dts b/arch/arm/boot/dts/sun5i-a13-utoo-p66.dts
>>>> index a8b0bcc..3d7ff10 100644
>>>> --- a/arch/arm/boot/dts/sun5i-a13-utoo-p66.dts
>>>> +++ b/arch/arm/boot/dts/sun5i-a13-utoo-p66.dts
>>>> @@ -83,22 +83,6 @@
>>>>  	allwinner,pins = "PG3";
>>>>  };
>>>>
>>>> -&i2c1 {
>>>> -	icn8318: touchscreen at 40 {
>>>> -		compatible = "chipone,icn8318";
>>>> -		reg = <0x40>;
>>>> -		interrupt-parent = <&pio>;
>>>> -		interrupts = <6 9 IRQ_TYPE_EDGE_FALLING>; /* EINT9 (PG9) */
>>>> -		pinctrl-names = "default";
>>>> -		pinctrl-0 = <&ts_wake_pin_p66>;
>>>> -		wake-gpios = <&pio 1 3 GPIO_ACTIVE_HIGH>; /* PB3 */
>>>> -		touchscreen-size-x = <800>;
>>>> -		touchscreen-size-y = <480>;
>>>> -		touchscreen-inverted-x;
>>>> -		touchscreen-swapped-x-y;
>>>> -	};
>>>> -};
>>>> -
>>>>  &mmc2 {
>>>>  	pinctrl-names = "default";
>>>>  	pinctrl-0 = <&mmc2_pins_a>;
>>>> @@ -121,20 +105,26 @@
>>>>  		allwinner,drive = <SUN4I_PINCTRL_10_MA>;
>>>>  		allwinner,pull = <SUN4I_PINCTRL_PULL_UP>;
>>>>  	};
>>>> -
>>>> -	ts_wake_pin_p66: ts_wake_pin at 0 {
>>>> -		allwinner,pins = "PB3";
>>>> -		allwinner,function = "gpio_out";
>>>> -		allwinner,drive = <SUN4I_PINCTRL_10_MA>;
>>>> -		allwinner,pull = <SUN4I_PINCTRL_NO_PULL>;
>>>> -	};
>>>> -
>>>>  };
>>>>
>>>>  &reg_usb0_vbus {
>>>>  	gpio = <&pio 1 4 GPIO_ACTIVE_HIGH>; /* PB4 */
>>>>  };
>>>>
>>>> +&touchscreen {
>>>> +	compatible = "chipone,icn8318";
>>>> +	reg = <0x40>;
>>>> +	/* The P66 uses a different EINT then the reference design */
>>>> +	interrupts = <6 9 IRQ_TYPE_EDGE_FALLING>; /* EINT9 (PG9) */
>>>> +	/* The icn8318 binding expects wake-gpios instead of power-gpios */
>>>> +	wake-gpios = <&pio 1 3 GPIO_ACTIVE_HIGH>; /* PB3 */
>>>> +	touchscreen-size-x = <800>;
>>>> +	touchscreen-size-y = <480>;
>>>> +	touchscreen-inverted-x;
>>>> +	touchscreen-swapped-x-y;
>>>> +	status = "okay";
>>>> +};
>>>> +
>>>>  &uart1 {
>>>>  	/* The P66 uses the uart pins as gpios */
>>>>  	status = "disabled";
>>>> diff --git a/arch/arm/boot/dts/sun5i-reference-design-tablet.dtsi b/arch/arm/boot/dts/sun5i-reference-design-tablet.dtsi
>>>> index 20cc940..7af488a 100644
>>>> --- a/arch/arm/boot/dts/sun5i-reference-design-tablet.dtsi
>>>> +++ b/arch/arm/boot/dts/sun5i-reference-design-tablet.dtsi
>>>> @@ -41,6 +41,7 @@
>>>>   */
>>>>  #include "sunxi-reference-design-tablet.dtsi"
>>>>
>>>> +#include <dt-bindings/interrupt-controller/irq.h>
>>>>  #include <dt-bindings/pwm/pwm.h>
>>>>
>>>>  / {
>>>> @@ -84,6 +85,23 @@
>>>>  };
>>>>
>>>>  &i2c1 {
>>>> +	/*
>>>> +	 * The gsl1680 is rated at 400KHz and it will not work reliable at
>>>> +	 * 100KHz, this has been confirmed on multiple different q8 tablets.
>>>> +	 * All other devices on this bus are also rated for 400KHz.
>>>> +	 */
>>>> +	clock-frequency = <400000>;
>>>> +
>>>> +	touchscreen: touchscreen {
>>>> +		interrupt-parent = <&pio>;
>>>> +		interrupts = <6 11 IRQ_TYPE_EDGE_FALLING>; /* EINT11 (PG11) */
>>>> +		pinctrl-names = "default";
>>>> +		pinctrl-0 = <&ts_power_pin>;
>>>> +		power-gpios = <&pio 1 3 GPIO_ACTIVE_HIGH>; /* PB3 */
>>>> +		/* Tablet dts must provide reg and compatible */
>>>> +		status = "disabled";
>>>> +	};
>>>> +
>>>>  	pcf8563: rtc at 51 {
>>>>  		compatible = "nxp,pcf8563";
>>>>  		reg = <0x51>;
>>>> @@ -125,6 +143,13 @@
>>>>  		allwinner,pull = <SUN4I_PINCTRL_PULL_UP>;
>>>>  	};
>>>>
>>>> +	ts_power_pin: ts_power_pin {
>>>> +		allwinner,pins = "PB3";
>>>> +		allwinner,function = "gpio_out";
>>>> +		allwinner,drive = <SUN4I_PINCTRL_10_MA>;
>>>> +		allwinner,pull = <SUN4I_PINCTRL_NO_PULL>;
>>>> +	};
>>>> +
>>>
>>> For the next release, we'll switch to the generic pin mux properties
>>> ("pins" and "function"), and we actually implemented the fact that the
>>> drive and pull properties are optional, so you can drop them both.
>>>
>>> You'll need next + http://lists.infradead.org/pipermail/linux-arm-kernel/2016-November/467123.html
>>
>> Ok, before I send a v2 first a question about this, for the touchscreen
>> case I actually need:
>>
>> 		allwinner,drive = <SUN4I_PINCTRL_10_MA>;
>> 		allwinner,pull = <SUN4I_PINCTRL_NO_PULL>;
>>
>> Because otherwise when the touchscreen controller is powered by a separate
>> regulator and that regulator is off, then it may draw just enough current
>> from its enable pin to be sort-of listening to the i2c bus and mess up
>> that bus.
>>
>> So is this the default, or do we get the power-on default when not
>> specifying these? If it is the power-on default then we do need to
>> specify these, because AFAICT the power-on drive strength typically
>> is 20 mA.
>
> Leaving them out will keep whatever state has been programmed. Putting
> them in the DT will force them to whatever value has been set.

Thanks for the answer, in the mean time I've send a v2 which leaves
them in using the new names (which according to your answer seems to
be the right thing to do).

Regards,

Hans