From 3de93e6ed2df6521e3f68fb45eec0bb4fe1bb218 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Fri, 8 Jul 2022 21:42:12 -0700 Subject: [PATCH] Input: goodix - call acpi_device_fix_up_power() in some cases On ACPI boards, when we cannot get the GPIOs to do a reset ourselves if necessary, call acpi_device_fix_up_power() to force the ACPI _PS0 method to run. On some devices without proper GPIO descriptions this will reset the touchscreen for us and this may be necessary for us to be able to communicate to the touchscreen at all. Specifically on an Aya Neo Next this change will cause the _PS0() ACPI function to call INIT() which does: Method (INIT, 0, Serialized) { TP_I = 0x00A50000 TP_R = 0x00A50000 Sleep (0x0A) TP_I = 0x00E50000 Sleep (One) TP_R = 0x00E50000 Sleep (0x06) TP_I = 0x00A50000 Sleep (0x3C) TP_I = 0x00041800 } On older kernels the ACPI core assumed a power-on was necessary by itself and would run _PS0 before our probe function runs, which can be seen from the GPIO pin ctrl registers in /sys/kernel/debug/gpio which match the above hex values with older kernels. With newer kernels before this change the GPIO pin ctrl registers do not match, indicating INIT() has not run and probing the touchscreen fails. This change makes Linux run _PS0() again fixing the touchscreen not working on the Aya Neo Next. Reported-and-tested-by: Maya Matuszczyk Signed-off-by: Hans de Goede Link: https://lore.kernel.org/r/20220618210233.208027-1-hdegoede@redhat.com Signed-off-by: Dmitry Torokhov --- drivers/input/touchscreen/goodix.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/input/touchscreen/goodix.c b/drivers/input/touchscreen/goodix.c index 3ad9870db1081..aa45a9fee6a01 100644 --- a/drivers/input/touchscreen/goodix.c +++ b/drivers/input/touchscreen/goodix.c @@ -900,6 +900,11 @@ static int goodix_add_acpi_gpio_mappings(struct goodix_ts_data *ts) } else { dev_warn(dev, "Unexpected ACPI resources: gpio_count %d, gpio_int_idx %d\n", ts->gpio_count, ts->gpio_int_idx); + /* + * On some devices _PS0 does a reset for us and + * sometimes this is necessary for things to work. + */ + acpi_device_fix_up_power(ACPI_COMPANION(dev)); return -EINVAL; } -- 2.39.5