[PATCH v2 0/2] Add ili9882t timing

[PATCH v2 0/2] Add ili9882t timing

[Cong Yang]

Add ili9882t dt-bindings and timing

Changes in v2:
- PATCH 1/2: fix ran make dt_binding_check warnings/errors.
- PATCH 1/2: remove oneOf,just enum.
- Link to v1: https://lore.kernel.org/all/20230602140948.2138668-1-yangcong5@huaqin.corp-partner.google.com/

Cong Yang (2):
  dt-bindings: input: touchscreen: Add ilitek 9882T touchscreen chip
  HID: i2c-hid: elan: Add ili9882t timing

 .../bindings/input/elan,ekth6915.yaml         | 23 ++++++++++++++++---
 drivers/hid/i2c-hid/i2c-hid-of-elan.c         | 20 ++++++++++++----
 2 files changed, 36 insertions(+), 7 deletions(-)

-- 
2.25.1

[PATCH v2 1/2] dt-bindings: input: touchscreen: Add ilitek 9882T touchscreen chip

[Cong Yang]

Add an ilitek touch screen chip ili9882t.

Signed-off-by: Cong Yang <yangcong5@huaqin.corp-partner.google.com>
---
 .../bindings/input/elan,ekth6915.yaml         | 23 ++++++++++++++++---
 1 file changed, 20 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
index 05e6f2df604c..f0e7ffdce605 100644
--- a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
+++ b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
@@ -15,11 +15,14 @@ description:
 
 properties:
   compatible:
-    items:
-      - const: elan,ekth6915
+    enum:
+      - elan,ekth6915
+      - ilitek,ili9882t
 
   reg:
-    const: 0x10
+    enum:
+      - 0x10
+      - 0x41
 
   interrupts:
     maxItems: 1
@@ -29,11 +32,13 @@ properties:
 
   vcc33-supply:
     description: The 3.3V supply to the touchscreen.
+                 If using ili9882t then this supply will not be needed.
 
   vccio-supply:
     description:
       The IO supply to the touchscreen. Need not be specified if this is the
       same as the 3.3V supply.
+      If using ili9882t, the IO supply is required.
 
 required:
   - compatible
@@ -41,6 +46,18 @@ required:
   - interrupts
   - vcc33-supply
 
+if:
+  properties:
+    compatible:
+      contains:
+        const: ilitek,ili9882t
+then:
+  required:
+    - compatible
+    - reg
+    - interrupts
+    - vccio-supply
+
 additionalProperties: false
 
 examples:
-- 
2.25.1

Re: [PATCH v2 1/2] dt-bindings: input: touchscreen: Add ilitek 9882T touchscreen chip

[Conor Dooley]

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Hey Cong Yang,

On Mon, Jun 05, 2023 at 02:05:23PM +0800, Cong Yang wrote:
> Add an ilitek touch screen chip ili9882t.

Could you add a comment here mentioning the relationship between these
chips?
On Mon, Jun 05, 2023 at 02:05:23PM +0800, Cong Yang wrote:

> Signed-off-by: Cong Yang <yangcong5@huaqin.corp-partner.google.com>
> ---
>  .../bindings/input/elan,ekth6915.yaml         | 23 ++++++++++++++++---
>  1 file changed, 20 insertions(+), 3 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> index 05e6f2df604c..f0e7ffdce605 100644
> --- a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> +++ b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> @@ -15,11 +15,14 @@ description:
>  
>  properties:
>    compatible:
> -    items:
> -      - const: elan,ekth6915
> +    enum:
> +      - elan,ekth6915
> +      - ilitek,ili9882t
>  
>    reg:
> -    const: 0x10
> +    enum:
> +      - 0x10
> +      - 0x41

Is 0x10 only valid for the elan,ekth6915 & 0x41 for the ilitek one?
If so, please add some enforcement of the values based on the
compatible.

>  
>    interrupts:
>      maxItems: 1
> @@ -29,11 +32,13 @@ properties:
>  


>    vcc33-supply:
>      description: The 3.3V supply to the touchscreen.
> +                 If using ili9882t then this supply will not be needed.
>  
>    vccio-supply:
>      description:
>        The IO supply to the touchscreen. Need not be specified if this is the
>        same as the 3.3V supply.
> +      If using ili9882t, the IO supply is required.

There's no need for these sort of comments, you can rely on the required
sections to describe these relationships.

Cheers,
Conor.

>  
>  required:
>    - compatible
> @@ -41,6 +46,18 @@ required:
>    - interrupts
>    - vcc33-supply
>  
> +if:
> +  properties:
> +    compatible:
> +      contains:
> +        const: ilitek,ili9882t
> +then:
> +  required:
> +    - compatible
> +    - reg
> +    - interrupts
> +    - vccio-supply
> +
>  additionalProperties: false
>  
>  examples:
> -- 
> 2.25.1

[-- Attachment #2: signature.asc --]
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Re: [PATCH v2 1/2] dt-bindings: input: touchscreen: Add ilitek 9882T touchscreen chip

[cong yang]

Hi,Conor,

On Mon, Jun 5, 2023 at 6:20 PM Conor Dooley <conor@kernel.org> wrote:
>
> Hey Cong Yang,
>
> On Mon, Jun 05, 2023 at 02:05:23PM +0800, Cong Yang wrote:
> > Add an ilitek touch screen chip ili9882t.
>
> Could you add a comment here mentioning the relationship between these
> chips?

Okay, I will add in V3 version.

> On Mon, Jun 05, 2023 at 02:05:23PM +0800, Cong Yang wrote:
>
> > Signed-off-by: Cong Yang <yangcong5@huaqin.corp-partner.google.com>
> > ---
> >  .../bindings/input/elan,ekth6915.yaml         | 23 ++++++++++++++++---
> >  1 file changed, 20 insertions(+), 3 deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> > index 05e6f2df604c..f0e7ffdce605 100644
> > --- a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> > +++ b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> > @@ -15,11 +15,14 @@ description:
> >
> >  properties:
> >    compatible:
> > -    items:
> > -      - const: elan,ekth6915
> > +    enum:
> > +      - elan,ekth6915
> > +      - ilitek,ili9882t
> >
> >    reg:
> > -    const: 0x10
> > +    enum:
> > +      - 0x10
> > +      - 0x41
>
> Is 0x10 only valid for the elan,ekth6915 & 0x41 for the ilitek one?
> If so, please add some enforcement of the values based on the
> compatible.

I don't think 0x10 is the only address for ekth6915,(nor is 0x41 the
only address for ili9882t). It depends on the hardware design.

>
> >
> >    interrupts:
> >      maxItems: 1
> > @@ -29,11 +32,13 @@ properties:
> >
>
>
> >    vcc33-supply:
> >      description: The 3.3V supply to the touchscreen.
> > +                 If using ili9882t then this supply will not be needed.
> >
> >    vccio-supply:
> >      description:
> >        The IO supply to the touchscreen. Need not be specified if this is the
> >        same as the 3.3V supply.
> > +      If using ili9882t, the IO supply is required.
>
> There's no need for these sort of comments, you can rely on the required
> sections to describe these relationships.

Got it ,thanks.


>
> Cheers,
> Conor.
>
> >
> >  required:
> >    - compatible
> > @@ -41,6 +46,18 @@ required:
> >    - interrupts
> >    - vcc33-supply
> >
> > +if:
> > +  properties:
> > +    compatible:
> > +      contains:
> > +        const: ilitek,ili9882t
> > +then:
> > +  required:
> > +    - compatible
> > +    - reg
> > +    - interrupts
> > +    - vccio-supply
> > +
> >  additionalProperties: false
> >
> >  examples:
> > --
> > 2.25.1

Re: [PATCH v2 1/2] dt-bindings: input: touchscreen: Add ilitek 9882T touchscreen chip

[Dmitry Torokhov]

On Tue, Jun 06, 2023 at 10:06:05AM +0800, cong yang wrote:
> Hi,Conor,
> 
> On Mon, Jun 5, 2023 at 6:20 PM Conor Dooley <conor@kernel.org> wrote:
> >
> > Hey Cong Yang,
> >
> > On Mon, Jun 05, 2023 at 02:05:23PM +0800, Cong Yang wrote:
> > > Add an ilitek touch screen chip ili9882t.
> >
> > Could you add a comment here mentioning the relationship between these
> > chips?
> 
> Okay, I will add in V3 version.
> 
> > On Mon, Jun 05, 2023 at 02:05:23PM +0800, Cong Yang wrote:
> >
> > > Signed-off-by: Cong Yang <yangcong5@huaqin.corp-partner.google.com>
> > > ---
> > >  .../bindings/input/elan,ekth6915.yaml         | 23 ++++++++++++++++---
> > >  1 file changed, 20 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> > > index 05e6f2df604c..f0e7ffdce605 100644
> > > --- a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> > > +++ b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> > > @@ -15,11 +15,14 @@ description:
> > >
> > >  properties:
> > >    compatible:
> > > -    items:
> > > -      - const: elan,ekth6915
> > > +    enum:
> > > +      - elan,ekth6915
> > > +      - ilitek,ili9882t
> > >
> > >    reg:
> > > -    const: 0x10
> > > +    enum:
> > > +      - 0x10
> > > +      - 0x41
> >
> > Is 0x10 only valid for the elan,ekth6915 & 0x41 for the ilitek one?
> > If so, please add some enforcement of the values based on the
> > compatible.
> 
> I don't think 0x10 is the only address for ekth6915,(nor is 0x41 the
> only address for ili9882t). It depends on the hardware design.

Only a handful of controllers allow switching between addresses, and
if they do they typically have a "main" and an "alternate" one, and not
something completely customizable. I do not believe Elan offers ways to
program different address, do they?

Thanks.

-- 
Dmitry

Re: [PATCH v2 1/2] dt-bindings: input: touchscreen: Add ilitek 9882T touchscreen chip

[Rob Herring]

On Tue, Jun 06, 2023 at 10:06:05AM +0800, cong yang wrote:
> Hi,Conor,
> 
> On Mon, Jun 5, 2023 at 6:20 PM Conor Dooley <conor@kernel.org> wrote:
> >
> > Hey Cong Yang,
> >
> > On Mon, Jun 05, 2023 at 02:05:23PM +0800, Cong Yang wrote:
> > > Add an ilitek touch screen chip ili9882t.
> >
> > Could you add a comment here mentioning the relationship between these
> > chips?
> 
> Okay, I will add in V3 version.
> 
> > On Mon, Jun 05, 2023 at 02:05:23PM +0800, Cong Yang wrote:
> >
> > > Signed-off-by: Cong Yang <yangcong5@huaqin.corp-partner.google.com>
> > > ---
> > >  .../bindings/input/elan,ekth6915.yaml         | 23 ++++++++++++++++---
> > >  1 file changed, 20 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> > > index 05e6f2df604c..f0e7ffdce605 100644
> > > --- a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> > > +++ b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> > > @@ -15,11 +15,14 @@ description:
> > >
> > >  properties:
> > >    compatible:
> > > -    items:
> > > -      - const: elan,ekth6915
> > > +    enum:
> > > +      - elan,ekth6915
> > > +      - ilitek,ili9882t
> > >
> > >    reg:
> > > -    const: 0x10
> > > +    enum:
> > > +      - 0x10
> > > +      - 0x41
> >
> > Is 0x10 only valid for the elan,ekth6915 & 0x41 for the ilitek one?
> > If so, please add some enforcement of the values based on the
> > compatible.
> 
> I don't think 0x10 is the only address for ekth6915,(nor is 0x41 the
> only address for ili9882t). It depends on the hardware design.

I'd just drop the values as we don't typically enforce 'reg' values.

Rob

Re: [PATCH v2 1/2] dt-bindings: input: touchscreen: Add ilitek 9882T touchscreen chip

[Krzysztof Kozlowski]

On 05/06/2023 08:05, Cong Yang wrote:
> Add an ilitek touch screen chip ili9882t.
> 
> Signed-off-by: Cong Yang <yangcong5@huaqin.corp-partner.google.com>
> ---
>  .../bindings/input/elan,ekth6915.yaml         | 23 ++++++++++++++++---
>  1 file changed, 20 insertions(+), 3 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> index 05e6f2df604c..f0e7ffdce605 100644
> --- a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> +++ b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> @@ -15,11 +15,14 @@ description:
>  
>  properties:
>    compatible:
> -    items:
> -      - const: elan,ekth6915
> +    enum:
> +      - elan,ekth6915
> +      - ilitek,ili9882t
>  
>    reg:
> -    const: 0x10
> +    enum:
> +      - 0x10
> +      - 0x41
>  
>    interrupts:
>      maxItems: 1
> @@ -29,11 +32,13 @@ properties:
>  
>    vcc33-supply:
>      description: The 3.3V supply to the touchscreen.
> +                 If using ili9882t then this supply will not be needed.

What does it mean "will not be needed"? Describe the hardware, not your
drivers.

I don't think you tested your DTS. Submit DTS users, because I do not
believe you are testing your patches. You already got such comment and I
don't see much of improvements here.

>  
>    vccio-supply:
>      description:
>        The IO supply to the touchscreen. Need not be specified if this is the
>        same as the 3.3V supply.
> +      If using ili9882t, the IO supply is required.

Don't repeat constraints in free form text.
>  
>  required:
>    - compatible
> @@ -41,6 +46,18 @@ required:
>    - interrupts
>    - vcc33-supply
>  
> +if:

Keep it in allOf. Will save you one indentation later.

> +  properties:
> +    compatible:
> +      contains:
> +        const: ilitek,ili9882t
> +then:
> +  required:
> +    - compatible
> +    - reg
> +    - interrupts

Don't duplicate.

> +    - vccio-supply


Best regards,
Krzysztof

Re: [PATCH v2 1/2] dt-bindings: input: touchscreen: Add ilitek 9882T touchscreen chip

[cong yang]

Hi,Krzysztof

On Mon, Jun 5, 2023 at 6:34 PM Krzysztof Kozlowski
<krzysztof.kozlowski@linaro.org> wrote:
>
> On 05/06/2023 08:05, Cong Yang wrote:
> > Add an ilitek touch screen chip ili9882t.
> >
> > Signed-off-by: Cong Yang <yangcong5@huaqin.corp-partner.google.com>
> > ---
> >  .../bindings/input/elan,ekth6915.yaml         | 23 ++++++++++++++++---
> >  1 file changed, 20 insertions(+), 3 deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> > index 05e6f2df604c..f0e7ffdce605 100644
> > --- a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> > +++ b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> > @@ -15,11 +15,14 @@ description:
> >
> >  properties:
> >    compatible:
> > -    items:
> > -      - const: elan,ekth6915
> > +    enum:
> > +      - elan,ekth6915
> > +      - ilitek,ili9882t
> >
> >    reg:
> > -    const: 0x10
> > +    enum:
> > +      - 0x10
> > +      - 0x41
> >
> >    interrupts:
> >      maxItems: 1
> > @@ -29,11 +32,13 @@ properties:
> >
> >    vcc33-supply:
> >      description: The 3.3V supply to the touchscreen.
> > +                 If using ili9882t then this supply will not be needed.
>
> What does it mean "will not be needed"? Describe the hardware, not your
> drivers.
>
> I don't think you tested your DTS. Submit DTS users, because I do not
> believe you are testing your patches. You already got such comment and I
> don't see much of improvements here.

I ran make dt_binding_check in the codebase root directory before
sending the V2 Patch, and there were no errors or warnings (the V1
version run reported some errors). Is there some other way to test DTS
?

>
> >
> >    vccio-supply:
> >      description:
> >        The IO supply to the touchscreen. Need not be specified if this is the
> >        same as the 3.3V supply.
> > +      If using ili9882t, the IO supply is required.
>
> Don't repeat constraints in free form text.

Got it.thanks.

> >
> >  required:
> >    - compatible
> > @@ -41,6 +46,18 @@ required:
> >    - interrupts
> >    - vcc33-supply
> >
> > +if:
>
> Keep it in allOf. Will save you one indentation later.

Got it.thanks.

>
> > +  properties:
> > +    compatible:
> > +      contains:
> > +        const: ilitek,ili9882t
> > +then:
> > +  required:
> > +    - compatible
> > +    - reg
> > +    - interrupts
>
> Don't duplicate.

Got it.thanks.

>
> > +    - vccio-supply
>
>
> Best regards,
> Krzysztof
>

Re: [PATCH v2 1/2] dt-bindings: input: touchscreen: Add ilitek 9882T touchscreen chip

[Krzysztof Kozlowski]

On 06/06/2023 04:18, cong yang wrote:
> Hi,Krzysztof
> 
> On Mon, Jun 5, 2023 at 6:34 PM Krzysztof Kozlowski
> <krzysztof.kozlowski@linaro.org> wrote:
>>
>> On 05/06/2023 08:05, Cong Yang wrote:
>>> Add an ilitek touch screen chip ili9882t.
>>>
>>> Signed-off-by: Cong Yang <yangcong5@huaqin.corp-partner.google.com>
>>> ---
>>>  .../bindings/input/elan,ekth6915.yaml         | 23 ++++++++++++++++---
>>>  1 file changed, 20 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
>>> index 05e6f2df604c..f0e7ffdce605 100644
>>> --- a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
>>> +++ b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
>>> @@ -15,11 +15,14 @@ description:
>>>
>>>  properties:
>>>    compatible:
>>> -    items:
>>> -      - const: elan,ekth6915
>>> +    enum:
>>> +      - elan,ekth6915
>>> +      - ilitek,ili9882t
>>>
>>>    reg:
>>> -    const: 0x10
>>> +    enum:
>>> +      - 0x10
>>> +      - 0x41
>>>
>>>    interrupts:
>>>      maxItems: 1
>>> @@ -29,11 +32,13 @@ properties:
>>>
>>>    vcc33-supply:
>>>      description: The 3.3V supply to the touchscreen.
>>> +                 If using ili9882t then this supply will not be needed.
>>
>> What does it mean "will not be needed"? Describe the hardware, not your
>> drivers.
>>
>> I don't think you tested your DTS. Submit DTS users, because I do not
>> believe you are testing your patches. You already got such comment and I
>> don't see much of improvements here.
> 
> I ran make dt_binding_check in the codebase root directory before
> sending the V2 Patch, and there were no errors or warnings (the V1
> version run reported some errors). Is there some other way to test DTS
> ?

https://www.linaro.org/blog/tips-and-tricks-for-validating-devicetree-sources-with-the-devicetree-schema/


Best regards,
Krzysztof

Re: [PATCH v2 1/2] dt-bindings: input: touchscreen: Add ilitek 9882T touchscreen chip

[Dmitry Torokhov]

On Mon, Jun 05, 2023 at 12:34:54PM +0200, Krzysztof Kozlowski wrote:
> On 05/06/2023 08:05, Cong Yang wrote:
> > Add an ilitek touch screen chip ili9882t.
> > 
> > Signed-off-by: Cong Yang <yangcong5@huaqin.corp-partner.google.com>
> > ---
> >  .../bindings/input/elan,ekth6915.yaml         | 23 ++++++++++++++++---
> >  1 file changed, 20 insertions(+), 3 deletions(-)
> > 
> > diff --git a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> > index 05e6f2df604c..f0e7ffdce605 100644
> > --- a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> > +++ b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> > @@ -15,11 +15,14 @@ description:
> >  
> >  properties:
> >    compatible:
> > -    items:
> > -      - const: elan,ekth6915
> > +    enum:
> > +      - elan,ekth6915
> > +      - ilitek,ili9882t
> >  
> >    reg:
> > -    const: 0x10
> > +    enum:
> > +      - 0x10
> > +      - 0x41
> >  
> >    interrupts:
> >      maxItems: 1
> > @@ -29,11 +32,13 @@ properties:
> >  
> >    vcc33-supply:
> >      description: The 3.3V supply to the touchscreen.
> > +                 If using ili9882t then this supply will not be needed.
> 
> What does it mean "will not be needed"? Describe the hardware, not your
> drivers.

I do not think it makes sense to merge Ilitek and Elan into a single
binding. The only thing that they have in common is that we are trying
to reuse drivers/hid/i2c-hid/i2c-hid-of-elan.c to handle reset timings
(which is also questionable IMO).

Maybe if we had a single unified binding for HID-over-I2C touchscreens
then combining would make more sense, at least to me...

Thanks.

-- 
Dmitry

Re: [PATCH v2 1/2] dt-bindings: input: touchscreen: Add ilitek 9882T touchscreen chip

[cong yang]

Hi,Dmitry

On Wed, Jun 7, 2023 at 2:51 AM Dmitry Torokhov
<dmitry.torokhov@gmail.com> wrote:
>
> On Mon, Jun 05, 2023 at 12:34:54PM +0200, Krzysztof Kozlowski wrote:
> > On 05/06/2023 08:05, Cong Yang wrote:
> > > Add an ilitek touch screen chip ili9882t.
> > >
> > > Signed-off-by: Cong Yang <yangcong5@huaqin.corp-partner.google.com>
> > > ---
> > >  .../bindings/input/elan,ekth6915.yaml         | 23 ++++++++++++++++---
> > >  1 file changed, 20 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> > > index 05e6f2df604c..f0e7ffdce605 100644
> > > --- a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> > > +++ b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml
> > > @@ -15,11 +15,14 @@ description:
> > >
> > >  properties:
> > >    compatible:
> > > -    items:
> > > -      - const: elan,ekth6915
> > > +    enum:
> > > +      - elan,ekth6915
> > > +      - ilitek,ili9882t
> > >
> > >    reg:
> > > -    const: 0x10
> > > +    enum:
> > > +      - 0x10
> > > +      - 0x41
> > >
> > >    interrupts:
> > >      maxItems: 1
> > > @@ -29,11 +32,13 @@ properties:
> > >
> > >    vcc33-supply:
> > >      description: The 3.3V supply to the touchscreen.
> > > +                 If using ili9882t then this supply will not be needed.
> >
> > What does it mean "will not be needed"? Describe the hardware, not your
> > drivers.
>
> I do not think it makes sense to merge Ilitek and Elan into a single
> binding. The only thing that they have in common is that we are trying
> to reuse drivers/hid/i2c-hid/i2c-hid-of-elan.c to handle reset timings
> (which is also questionable IMO).
>
> Maybe if we had a single unified binding for HID-over-I2C touchscreens
> then combining would make more sense, at least to me...
>

Okay, thanks for the suggestion, I will add an ilitek binding.

> Thanks.
>
> --
> Dmitry

[PATCH v2 2/2] HID: i2c-hid: elan: Add ili9882t timing

[Cong Yang]

The ili9882t is a TDDI IC (Touch with Display Driver). The datasheet
specifies there should be 60ms between touch SDA sleep and panel RESX.
Doug's series[1] allows panels and touchscreens to power on/off together,
so we can add the 65 ms delay in i2c_hid_core_suspend before panel_unprepare.

[1]: https: //lore.kernel.org/all/20230523193017.4109557-1-dianders@chromium.org/

Signed-off-by: Cong Yang <yangcong5@huaqin.corp-partner.google.com>
---
 drivers/hid/i2c-hid/i2c-hid-of-elan.c | 20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/drivers/hid/i2c-hid/i2c-hid-of-elan.c b/drivers/hid/i2c-hid/i2c-hid-of-elan.c
index 76ddc8be1cbb..411d7ea2725d 100644
--- a/drivers/hid/i2c-hid/i2c-hid-of-elan.c
+++ b/drivers/hid/i2c-hid/i2c-hid-of-elan.c
@@ -18,7 +18,8 @@
 #include "i2c-hid.h"
 
 struct elan_i2c_hid_chip_data {
-	unsigned int post_gpio_reset_delay_ms;
+	unsigned int post_gpio_reset_on_delay_ms;
+	unsigned int post_gpio_reset_off_delay_ms;
 	unsigned int post_power_delay_ms;
 	u16 hid_descriptor_address;
 };
@@ -52,8 +53,8 @@ static int elan_i2c_hid_power_up(struct i2chid_ops *ops)
 		msleep(ihid_elan->chip_data->post_power_delay_ms);
 
 	gpiod_set_value_cansleep(ihid_elan->reset_gpio, 0);
-	if (ihid_elan->chip_data->post_gpio_reset_delay_ms)
-		msleep(ihid_elan->chip_data->post_gpio_reset_delay_ms);
+	if (ihid_elan->chip_data->post_gpio_reset_on_delay_ms)
+		msleep(ihid_elan->chip_data->post_gpio_reset_on_delay_ms);
 
 	return 0;
 }
@@ -64,6 +65,9 @@ static void elan_i2c_hid_power_down(struct i2chid_ops *ops)
 		container_of(ops, struct i2c_hid_of_elan, ops);
 
 	gpiod_set_value_cansleep(ihid_elan->reset_gpio, 1);
+	if (ihid_elan->chip_data->post_gpio_reset_off_delay_ms)
+		msleep(ihid_elan->chip_data->post_gpio_reset_off_delay_ms);
+
 	regulator_disable(ihid_elan->vccio);
 	regulator_disable(ihid_elan->vcc33);
 }
@@ -101,12 +105,20 @@ static int i2c_hid_of_elan_probe(struct i2c_client *client)
 
 static const struct elan_i2c_hid_chip_data elan_ekth6915_chip_data = {
 	.post_power_delay_ms = 1,
-	.post_gpio_reset_delay_ms = 300,
+	.post_gpio_reset_on_delay_ms = 300,
+	.hid_descriptor_address = 0x0001,
+};
+
+static const struct elan_i2c_hid_chip_data ilitek_ili9882t_chip_data = {
+	.post_power_delay_ms = 1,
+	.post_gpio_reset_on_delay_ms = 200,
+	.post_gpio_reset_off_delay_ms = 65,
 	.hid_descriptor_address = 0x0001,
 };
 
 static const struct of_device_id elan_i2c_hid_of_match[] = {
 	{ .compatible = "elan,ekth6915", .data = &elan_ekth6915_chip_data },
+	{ .compatible = "ilitek,ili9882t", .data = &ilitek_ili9882t_chip_data },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, elan_i2c_hid_of_match);
-- 
2.25.1