[PATCH 5/5] platform/x86: intel-vbtn: Fix probe failure on devices with only switches

From: Hans de Goede
Date: Sat May 02 2020 - 14:30:13 EST


On some devices the INT33D6 vbtn device is only used to report
tablet-mode / docked status (switches) and there are no vbtn managed
buttons.

On these devices there is no VBDL object.

Move the VBDL check to a intel_vbtn_has_buttons() helper and only exit
from intel_vbtn_probe() with -ENODEV when there are both no buttons and
no switches. Also only report the buttons being present to userspace if
the has_buttons check has succeeded.

Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
drivers/platform/x86/intel-vbtn.c | 21 +++++++++++++++++----
1 file changed, 17 insertions(+), 4 deletions(-)

diff --git a/drivers/platform/x86/intel-vbtn.c b/drivers/platform/x86/intel-vbtn.c
index 4921fc15dc6c..4efc70b693a7 100644
--- a/drivers/platform/x86/intel-vbtn.c
+++ b/drivers/platform/x86/intel-vbtn.c
@@ -55,6 +55,7 @@ static const struct key_entry intel_vbtn_switchmap[] = {
struct intel_vbtn_priv {
struct key_entry keymap[KEYMAP_LEN];
struct input_dev *input_dev;
+ bool has_buttons;
bool has_switches;
bool wakeup_mode;
};
@@ -64,7 +65,7 @@ static int intel_vbtn_input_setup(struct platform_device *device)
struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
int ret, keymap_len = 0;

- if (true) {
+ if (priv->has_buttons) {
memcpy(&priv->keymap[keymap_len], intel_vbtn_keymap,
ARRAY_SIZE(intel_vbtn_keymap) *
sizeof(struct key_entry));
@@ -155,6 +156,14 @@ static void detect_tablet_mode(struct platform_device *device)
input_report_switch(priv->input_dev, SW_DOCK, m);
}

+static bool intel_vbtn_has_buttons(acpi_handle handle)
+{
+ acpi_status status;
+
+ status = acpi_evaluate_object(handle, "VBDL", NULL, NULL);
+ return ACPI_SUCCESS(status);
+}
+
static bool intel_vbtn_has_switches(acpi_handle handle)
{
const char *chassis_type = dmi_get_system_info(DMI_CHASSIS_TYPE);
@@ -181,12 +190,15 @@ static bool intel_vbtn_has_switches(acpi_handle handle)
static int intel_vbtn_probe(struct platform_device *device)
{
acpi_handle handle = ACPI_HANDLE(&device->dev);
+ bool has_buttons, has_switches;
struct intel_vbtn_priv *priv;
acpi_status status;
int err;

- status = acpi_evaluate_object(handle, "VBDL", NULL, NULL);
- if (ACPI_FAILURE(status)) {
+ has_buttons = intel_vbtn_has_buttons(handle);
+ has_switches = intel_vbtn_has_switches(handle);
+
+ if (!has_buttons && !has_switches) {
dev_warn(&device->dev, "failed to read Intel Virtual Button driver\n");
return -ENODEV;
}
@@ -196,7 +208,8 @@ static int intel_vbtn_probe(struct platform_device *device)
return -ENOMEM;
dev_set_drvdata(&device->dev, priv);

- priv->has_switches = intel_vbtn_has_switches(handle);
+ priv->has_buttons = has_buttons;
+ priv->has_switches = has_switches;

err = intel_vbtn_input_setup(device);
if (err) {
--
2.26.0