Re: [PATCH v10 1/4] Input: Add driver for Cypress Generation 5 touchscreen

[James Hilliard <james.hilliard1@gmail.com>]

On Wed, Oct 26, 2022 at 6:05 AM Alistair Francis <alistair@alistair23.me> wrote:
>
> This is the basic driver for the Cypress TrueTouch Gen5 touchscreen
> controllers. This driver supports only the I2C bus but it uses regmap
> so SPI support could be added later.
> The touchscreen can retrieve some defined zone that are handled as
> buttons (according to the hardware). That is why it handles
> button and multitouch events.
>
> Reviewed-by: Maxime Ripard <maxime.ripard@bootlin.com>
> Signed-off-by: Mylène Josserand <mylene.josserand@bootlin.com>
> Signed-off-by: Alistair Francis <alistair@alistair23.me>
> Tested-by: Andreas Kemnade <andreas@kemnade.info> # Kobo Clara HD
> Tested-by: Peter Geis <pgwipeout@gmail.com>
> ---
>  drivers/input/touchscreen/Kconfig   |  16 +
>  drivers/input/touchscreen/Makefile  |   1 +
>  drivers/input/touchscreen/cyttsp5.c | 902 ++++++++++++++++++++++++++++
>  3 files changed, 919 insertions(+)
>  create mode 100644 drivers/input/touchscreen/cyttsp5.c
>
> +
> +static int cyttsp5_hid_output_bl_launch_app(struct cyttsp5 *ts)
> +{
> +       int rc;
> +       u8 cmd[HID_OUTPUT_BL_LAUNCH_APP];
> +       u16 crc;
> +
> +       put_unaligned_le16(HID_OUTPUT_BL_LAUNCH_APP_SIZE, cmd);
> +       cmd[2] = HID_BL_OUTPUT_REPORT_ID;
> +       cmd[3] = 0x0; /* Reserved */
> +       cmd[4] = HID_OUTPUT_BL_SOP;
> +       cmd[5] = HID_OUTPUT_BL_LAUNCH_APP;
> +       put_unaligned_le16(0x00, &cmd[6]);
> +       crc = crc_itu_t(0xFFFF, &cmd[4], 4);
> +       put_unaligned_le16(crc, &cmd[8]);
> +       cmd[10] = HID_OUTPUT_BL_EOP;
> +
> +       rc = cyttsp5_write(ts, HID_OUTPUT_REG, cmd,
> +                          HID_OUTPUT_BL_LAUNCH_APP_SIZE);
> +       if (rc) {
> +               dev_err(ts->dev, "Failed to write command %d", rc);
> +               return rc;
> +       }
> +
> +       rc = wait_for_completion_interruptible_timeout(&ts->cmd_done,
> +                                               msecs_to_jiffies(CY_HID_OUTPUT_TIMEOUT_MS));
> +       if (rc <= 0) {
> +               dev_err(ts->dev, "HID output cmd execution timed out\n");
> +               rc = -ETIMEDOUT;
> +               return rc;
> +       }

I've been seeing this timeout error somewhat randomly on a Variscite i.MX6
QUAD/DUAL VAR-SOM-MX6 Custom Board based device at startup:

[    2.234089] cyttsp5 2-0024: HID output cmd execution timed out
[    2.239957] cyttsp5 2-0024: Error on launch app r=-110
[    2.245150] cyttsp5 2-0024: Fail initial startup r=-110
[    2.257502] cyttsp5: probe of 2-0024 failed with error -110

When it doesn't error I just see this:

[    2.061176] input: cyttsp5 as
/devices/platform/soc/2100000.bus/21a8000.i2c/i2c-2/2-0024/input/input0

I'm not sure if this is a driver issue or potentially a device tree issue, the
upstream kernel device tree node looks like this:

touchscreen@24 {
    compatible = "cypress,tt21000";
    reg = <0x24>;
    interrupt-parent = <&gpio3>;
    interrupts = <7 IRQ_TYPE_EDGE_FALLING>;
    reset-gpios = <&gpio5 13 GPIO_ACTIVE_LOW>;
    vdd-supply = <&reg_3p3v>;
    touchscreen-size-x = <880>;
    touchscreen-size-y = <1280>;
};

Full device tree here:
https://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux.git/tree/arch/arm/boot/dts/nxp/imx/imx6q-var-mx6customboard.dts?h=for-next

The original vendor device tree node for the downstream kernel looked like this:
tsc@0x24 {
    compatible = "cy,cyttsp5_i2c_adapter";
    reg = <0x24>;
    interrupts = <0x07 0x02>;
    interrupt-parent = <0x07>;
    cy,adapter_id = "cyttsp5_i2c_adapter";

    cy,core {
        cy,name = "cyttsp5_core";

        cy,irq_gpio = <71>;
        cy,rst_gpio = <141>;
        cy,hid_desc_register = <0x01>;
        /* CY_CORE_FLAG_RESTORE_PARAMETERS */
        cy,flags = <4>;
        /* CY_CORE_EWG_NONE */
        cy,easy_wakeup_gesture = <0>;
        cy,btn_keys-tag = <0>;

        cy,mt {
            cy,name = "cyttsp5_mt";

            cy,inp_dev_name = "cyttsp5_mt";
            /* CY_MT_FLAG_NONE */
            cy,flags = <0x00>;
            cy,abs =
                /* ABS_MT_POSITION_X, CY_ABS_MIN_X, CY_ABS_MAX_X, 0, 0 */
                <0x35 0 880 0 0
                /* ABS_MT_POSITION_Y, CY_ABS_MIN_Y, CY_ABS_MAX_Y, 0, 0 */
                0x36 0 1280 0 0
                /* ABS_MT_PRESSURE, CY_ABS_MIN_P, CY_ABS_MAX_P, 0, 0 */
                0x3a 0 255 0 0
                /* CY_IGNORE_VALUE, CY_ABS_MIN_W, CY_ABS_MAX_W, 0, 0 */
                0xffff 0 255 0 0
                /* ABS_MT_TRACKING_ID, CY_ABS_MIN_T, CY_ABS_MAX_T, 0, 0 */
                0x39 0 15 0 0
                /* ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0 */
                0x30 0 255 0 0
                /* ABS_MT_TOUCH_MINOR, 0, 255, 0, 0 */
                0x31 0 255 0 0
                /* ABS_MT_ORIENTATION, -127, 127, 0, 0 */
                0x34 0xffffff81 127 0 0
                /* ABS_MT_TOOL_TYPE, 0, MT_TOOL_MAX, 0, 0 */
                0x37 0 1 0 0
                /* ABS_MT_DISTANCE, 0, 255, 0, 0 */
                0x3b 0 255 0 0>;
        };
    };
};