Re: [PATCH v7 0/4] Add support for the Cypress cyttsp5

[Alistair Francis]

On Wed, Apr 20, 2022 at 10:25 PM Alistair Francis <alistair23@xxxxxxxxx> wrote:
>
> On Wed, Mar 23, 2022 at 10:00 PM Alistair Francis
> <alistair@xxxxxxxxxxxxx> wrote:
> >
> > This patch series builds on top of [1] and adds support for the cyttsp5
> > touchscreen controller for the reMarkable 2.
> >
> > I first tried to add an I2C HID device. Although the cyttsp5 has some HID
> > looking aspects it is not HID compatible. Just in trying to probe the device
> > I found:
> >  - The HID descriptor has extra padding
> >  - The HID descriptor sets the high bytes of the descriptor length
> >  - The HID descriptor has extra unrecognised tags
> >  - The HID reset command doesn't appear to work
> >
> > I don't think there is a way to use the I2C HID framework with the cyttsp5.
> > For anyone interested you can see the work here [2]. In that branch though I
> > can only obtain a HID descriptor, nothing else works without more core
> > changes.
> >
> > So instead I rebased the series from [1]. Converted to the new yaml DTS
> > documentation, added regulator support and fixed a x/y miscalculation bug.
>
> The DT bindings have been reviewed, any comments on the driver
> implementation? It has been tested on a few different devices

Any comments? It would be great to try and get this in 5.19

Alistair

>
> Alistair
>
> >
> > 1: https://lwn.net/ml/linux-kernel/20180703094309.18514-1-mylene.josserand@xxxxxxxxxxx/
> > 2: https://github.com/alistair23/linux/commits/rM2-mainline-cyttsp5-hid
> >
> > v7:
> >  - Fix device tree warnings
> > v6:
> >  - Use reg for the button properties
> > v5:
> >  - Address review comments from v4
> >
> > Alistair Francis (4):
> >   Input: Add driver for Cypress Generation 5 touchscreen
> >   dt-bindings: input: Add Cypress TT2100 touchscreen controller
> >   ARM: imx_v6_v7_defconfig: Enable the cyttsp5 touchscreen
> >   ARM: dts: imx7d-remarkable2: Enable the cyttsp5
> >
> >  .../input/touchscreen/cypress,tt21000.yaml    | 101 ++
> >  arch/arm/boot/dts/imx7d-remarkable2.dts       | 100 ++
> >  arch/arm/configs/imx_v6_v7_defconfig          |   1 +
> >  drivers/input/touchscreen/Kconfig             |  16 +
> >  drivers/input/touchscreen/Makefile            |   1 +
> >  drivers/input/touchscreen/cyttsp5.c           | 902 ++++++++++++++++++
> >  6 files changed, 1121 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/input/touchscreen/cypress,tt21000.yaml
> >  create mode 100644 drivers/input/touchscreen/cyttsp5.c
> >
> > --
> > 2.35.1
> >