# \[PATCH v4 0/4\] Add support for the Cypress cyttsp5 - From: Alistair Francis \ - Date: 2021-12-22 12:46:14 - List: linux-arm-kernel - Page: https://ratatoskr.run/linux-arm-kernel/2021/12/1616657 - Thread: https://ratatoskr.run/linux-devicetree/2021/12/1616657/t.md ```text 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 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ```