platform/x86: intel-vbtn: Fix probe failure on devices with only switches

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@redhat.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

diff --git a/drivers/platform/x86/intel-vbtn.c b/drivers/platform/x86/intel-vbtn.c
index 4921fc15dc6c7fe441ec88e97477d2ec967cf171..4efc70b693a75179e64c70c3886468e22143c2d5 100644 (file)
--- 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) {