[PATCH v4 0/4] Add support for the Cypress cyttsp5
Alistair Francis
alistair at alistair23.me
Wed Dec 22 04:45:59 PST 2021
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.
1: https://lwn.net/ml/linux-kernel/20180703094309.18514-1-mylene.josserand@bootlin.com/
2: https://github.com/alistair23/linux/commits/rM2-mainline-cyttsp5-hid
Alistair Francis (2):
ARM: imx_v6_v7_defconfig: Enable the cyttsp5 touchscreen
ARM: dts: imx7d-remarkable2: Enable the cyttsp5
Mylène Josserand (2):
Input: Add driver for Cypress Generation 5 touchscreen
dt-bindings: input: Add Cypress TT2100 touchscreen controller
.../input/touchscreen/cypress,tt21000.yaml | 92 ++
arch/arm/boot/dts/imx7d-remarkable2.dts | 89 ++
arch/arm/configs/imx_v6_v7_defconfig | 1 +
drivers/input/touchscreen/Kconfig | 14 +
drivers/input/touchscreen/Makefile | 1 +
drivers/input/touchscreen/cyttsp5.c | 922 ++++++++++++++++++
6 files changed, 1119 insertions(+)
create mode 100644 Documentation/devicetree/bindings/input/touchscreen/cypress,tt21000.yaml
create mode 100644 drivers/input/touchscreen/cyttsp5.c
--
2.31.1
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