[PATCH] platform/x86: dell-wmi: Recognise or support new switches

From: Troy Rollo
Date: Sat Sep 18 2021 - 03:35:13 EST


Adds support for:

- Dell Inspiron 2in1 tablet mode switch notifications. These are
delivered by a type 0x0011 message with code 0xe070, followed by a
flag (1 for laptop mode, 0 for tablet mode).

- Recognising (but not otherwise processing) the Dell Ultra Performance
mode request switch. This is delivered by a type 0x0012 message with
code 0x000d, followed by a parameter that is either 1 or 2. It is
not clear what (if anything) should be done with this notification, so
it is ignored.

Signed-off-by: Troy Rollo <linux2021@xxxxxxxxxxxxxxx>
---
drivers/platform/x86/dell/dell-wmi-base.c | 76 ++++++++++++++++++++---
1 file changed, 66 insertions(+), 10 deletions(-)

diff --git a/drivers/platform/x86/dell/dell-wmi-base.c b/drivers/platform/x86/dell/dell-wmi-base.c
index 089c125e18f7..e07d3ba85a3f 100644
--- a/drivers/platform/x86/dell/dell-wmi-base.c
+++ b/drivers/platform/x86/dell/dell-wmi-base.c
@@ -40,6 +40,7 @@ static bool wmi_requires_smbios_request;

struct dell_wmi_priv {
struct input_dev *input_dev;
+ struct input_dev *tabletswitch_dev;
u32 interface_version;
};

@@ -309,6 +310,9 @@ static const struct key_entry dell_wmi_keymap_type_0010[] = {
* Keymap for WMI events of type 0x0011
*/
static const struct key_entry dell_wmi_keymap_type_0011[] = {
+ /* Reflex keyboard switch on 2n1 devices */
+ { KE_IGNORE, 0xe070, { KEY_RESERVED } },
+
/* Battery unplugged */
{ KE_IGNORE, 0xfff0, { KEY_RESERVED } },

@@ -340,21 +344,55 @@ static const struct key_entry dell_wmi_keymap_type_0011[] = {
* They are events with extended data
*/
static const struct key_entry dell_wmi_keymap_type_0012[] = {
+ /* Ultra-performance mode switch request */
+ { KE_IGNORE, 0x000d, { KEY_RESERVED } },
+
/* Fn-lock button pressed */
{ KE_IGNORE, 0xe035, { KEY_RESERVED } },
};

-static void dell_wmi_process_key(struct wmi_device *wdev, int type, int code)
+static void dell_wmi_switch_event(struct input_dev **subdev,
+ const char *devname,
+ int switchid,
+ int value)
+{
+ if (!*subdev) {
+ struct input_dev *dev = input_allocate_device();
+
+ if (!dev) {
+ pr_warn("could not allocate device for %s\n", devname);
+ return;
+ }
+ __set_bit(EV_SW, (dev)->evbit);
+ __set_bit(switchid, (dev)->swbit);
+
+ (dev)->name = devname;
+ (dev)->id.bustype = BUS_HOST;
+ if (input_register_device(dev)) {
+ input_free_device(dev);
+ pr_warn("could not register device for %s\n", devname);
+ return;
+ }
+ *subdev = dev;
+ }
+
+ input_report_switch(*subdev, switchid, value);
+ input_sync(*subdev);
+}
+
+static int dell_wmi_process_key(struct wmi_device *wdev, int type, int code, u16 *buffer, int remaining)
{
struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
const struct key_entry *key;
+ int used = 0;
+ int value = 1;

key = sparse_keymap_entry_from_scancode(priv->input_dev,
(type << 16) | code);
if (!key) {
pr_info("Unknown key with type 0x%04x and code 0x%04x pressed\n",
type, code);
- return;
+ return 0;
}

pr_debug("Key with type 0x%04x and code 0x%04x pressed\n", type, code);
@@ -363,16 +401,27 @@ static void dell_wmi_process_key(struct wmi_device *wdev, int type, int code)
if ((key->keycode == KEY_BRIGHTNESSUP ||
key->keycode == KEY_BRIGHTNESSDOWN) &&
acpi_video_handles_brightness_key_presses())
- return;
+ return 0;

if (type == 0x0000 && code == 0xe025 && !wmi_requires_smbios_request)
- return;
+ return 0;

- if (key->keycode == KEY_KBDILLUMTOGGLE)
+ if (key->keycode == KEY_KBDILLUMTOGGLE) {
dell_laptop_call_notifier(
DELL_LAPTOP_KBD_BACKLIGHT_BRIGHTNESS_CHANGED, NULL);
+ } else if (type == 0x0011 && code == 0xe070 && remaining > 0) {
+ dell_wmi_switch_event(&priv->tabletswitch_dev,
+ "Dell tablet mode switch",
+ SW_TABLET_MODE, !buffer[0]);
+ return 1;
+ } else if (type == 0x0012 && code == 0x000d && remaining > 0) {
+ value = (buffer[2] == 2);
+ used = 1;
+ }

- sparse_keymap_report_entry(priv->input_dev, key, 1, true);
+ sparse_keymap_report_entry(priv->input_dev, key, value, true);
+
+ return used;
}

static void dell_wmi_notify(struct wmi_device *wdev,
@@ -430,21 +479,26 @@ static void dell_wmi_notify(struct wmi_device *wdev,
case 0x0000: /* One key pressed or event occurred */
if (len > 2)
dell_wmi_process_key(wdev, buffer_entry[1],
- buffer_entry[2]);
+ buffer_entry[2],
+ buffer_entry + 3,
+ len - 3);
/* Extended data is currently ignored */
break;
case 0x0010: /* Sequence of keys pressed */
case 0x0011: /* Sequence of events occurred */
for (i = 2; i < len; ++i)
- dell_wmi_process_key(wdev, buffer_entry[1],
- buffer_entry[i]);
+ i += dell_wmi_process_key(wdev, buffer_entry[1],
+ buffer_entry[i],
+ buffer_entry + i,
+ len - i - 1);
break;
case 0x0012:
if ((len > 4) && dell_privacy_process_event(buffer_entry[1], buffer_entry[3],
buffer_entry[4]))
/* dell_privacy_process_event has handled the event */;
else if (len > 2)
- dell_wmi_process_key(wdev, buffer_entry[1], buffer_entry[2]);
+ dell_wmi_process_key(wdev, buffer_entry[1], buffer_entry[2],
+ buffer_entry + 3, len - 3);
break;
default: /* Unknown event */
pr_info("Unknown WMI event type 0x%x\n",
@@ -661,6 +715,8 @@ static void dell_wmi_input_destroy(struct wmi_device *wdev)
struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev);

input_unregister_device(priv->input_dev);
+ if (priv->tabletswitch_dev)
+ input_unregister_device(priv->tabletswitch_dev);
}

/*
--
2.30.2