Input: goodix - add support for controlling the IRQ pin through ACPI methods

Some Apollo Lake (x86, UEFI + ACPI) devices only list the reset GPIO
in their _CRS table and the bit-banging of the IRQ line necessary to
wake-up the controller from suspend can be done by calling 2 Goodix
custom / specific ACPI methods.

This commit adds support for controlling the IRQ line in this matter,
allowing us to properly suspend the touchscreen controller on such
devices.

BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1786317
BugLink: https://github.com/nexus511/gpd-ubuntu-packages/issues/10
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=199207
Reviewed-by: Bastien Nocera <hadess@hadess.net>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20200307121505.3707-6-hdegoede@redhat.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

diff --git a/drivers/input/touchscreen/goodix.c b/drivers/input/touchscreen/goodix.c
index 37862f7..8e31b4b 100644 (file)
--- a/drivers/input/touchscreen/goodix.c
+++ b/drivers/input/touchscreen/goodix.c
@@ -35,6 +35,7 @@ enum goodix_irq_pin_access_method {
        IRQ_PIN_ACCESS_NONE,
        IRQ_PIN_ACCESS_GPIO,
        IRQ_PIN_ACCESS_ACPI_GPIO,
+       IRQ_PIN_ACCESS_ACPI_METHOD,
 };
 
 struct goodix_chip_data {
@@ -532,6 +533,9 @@ static int goodix_send_cfg(struct goodix_ts_data *ts,
 static int goodix_irq_direction_output(struct goodix_ts_data *ts,
                                       int value)
 {
+       struct device *dev = &ts->client->dev;
+       acpi_status status;
+
        switch (ts->irq_pin_access_method) {
        case IRQ_PIN_ACCESS_NONE:
                dev_err(&ts->client->dev,
@@ -546,6 +550,10 @@ static int goodix_irq_direction_output(struct goodix_ts_data *ts,
                 * as active-low, use output_raw to avoid the value inversion.
                 */
                return gpiod_direction_output_raw(ts->gpiod_int, value);
+       case IRQ_PIN_ACCESS_ACPI_METHOD:
+               status = acpi_execute_simple_method(ACPI_HANDLE(dev),
+                                                   "INTO", value);
+               return ACPI_SUCCESS(status) ? 0 : -EIO;
        }
 
        return -EINVAL; /* Never reached */
@@ -553,6 +561,9 @@ static int goodix_irq_direction_output(struct goodix_ts_data *ts,
 
 static int goodix_irq_direction_input(struct goodix_ts_data *ts)
 {
+       struct device *dev = &ts->client->dev;
+       acpi_status status;
+
        switch (ts->irq_pin_access_method) {
        case IRQ_PIN_ACCESS_NONE:
                dev_err(&ts->client->dev,
@@ -562,6 +573,10 @@ static int goodix_irq_direction_input(struct goodix_ts_data *ts)
        case IRQ_PIN_ACCESS_GPIO:
        case IRQ_PIN_ACCESS_ACPI_GPIO:
                return gpiod_direction_input(ts->gpiod_int);
+       case IRQ_PIN_ACCESS_ACPI_METHOD:
+               status = acpi_evaluate_object(ACPI_HANDLE(dev), "INTI",
+                                             NULL, NULL);
+               return ACPI_SUCCESS(status) ? 0 : -EIO;
        }
 
        return -EINVAL; /* Never reached */
@@ -656,6 +671,11 @@ static const struct acpi_gpio_mapping acpi_goodix_int_last_gpios[] = {
        { },
 };
 
+static const struct acpi_gpio_mapping acpi_goodix_reset_only_gpios[] = {
+       { GOODIX_GPIO_RST_NAME "-gpios", &first_gpio, 1 },
+       { },
+};
+
 static int goodix_resource(struct acpi_resource *ares, void *data)
 {
        struct goodix_ts_data *ts = data;
@@ -713,6 +733,12 @@ static int goodix_add_acpi_gpio_mappings(struct goodix_ts_data *ts)
        } else if (ts->gpio_count == 2 && ts->gpio_int_idx == 1) {
                ts->irq_pin_access_method = IRQ_PIN_ACCESS_ACPI_GPIO;
                gpio_mapping = acpi_goodix_int_last_gpios;
+       } else if (ts->gpio_count == 1 && ts->gpio_int_idx == -1 &&
+                  acpi_has_method(ACPI_HANDLE(dev), "INTI") &&
+                  acpi_has_method(ACPI_HANDLE(dev), "INTO")) {
+               dev_info(dev, "Using ACPI INTI and INTO methods for IRQ pin access\n");
+               ts->irq_pin_access_method = IRQ_PIN_ACCESS_ACPI_METHOD;
+               gpio_mapping = acpi_goodix_reset_only_gpios;
        } else if (is_byt() && ts->gpio_count == 2 && ts->gpio_int_idx == -1) {
                dev_info(dev, "No ACPI GpioInt resource, assuming that the GPIO order is reset, int\n");
                ts->irq_pin_access_method = IRQ_PIN_ACCESS_ACPI_GPIO;
@@ -809,6 +835,10 @@ retry_get_irq_gpio:
                if (!ts->gpiod_int || !ts->gpiod_rst)
                        ts->irq_pin_access_method = IRQ_PIN_ACCESS_NONE;
                break;
+       case IRQ_PIN_ACCESS_ACPI_METHOD:
+               if (!ts->gpiod_rst)
+                       ts->irq_pin_access_method = IRQ_PIN_ACCESS_NONE;
+               break;
        default:
                if (ts->gpiod_int && ts->gpiod_rst) {
                        ts->reset_controller_at_probe = true;