drivers/platform/x86/lenovo/thinkpad_acpi.c | 85 ++++++++++++++++++++- 1 file changed, 83 insertions(+), 2 deletions(-)
ThinkPad X1 Fold 16 Gen 1 firmware reports whether the keyboard is magnetically
attached (on the screen), but thinkpad-acpi does not expose this to userspace.
The state can be obtained via ACPI methods: GDST (get device state).
Add a read-only keyboard_attached_on_screen sysfs attribute, gated by
a DMI match. The state is read directly from the EC.
Cache the state and emit a sysfs notification on
TP_HKEY_EV_TABLET_CHANGED (0x60c0) when it changes. Initialize the cache during
hotkey setup and refresh it before the resume notification to keep the state
consistent across suspend and resume.
Signed-off-by: Pit Henrich <pithenrich2d@gmail.com>
---
This replaced the v1 patch in:
https://lore.kernel.org/all/20260314142236.74514-1-pithenrich2d@gmail.com/
Changes v1 -> v2:
* Use ACPI method instead of using the EC directly (thanks Mark).
---
drivers/platform/x86/lenovo/thinkpad_acpi.c | 85 ++++++++++++++++++++-
1 file changed, 83 insertions(+), 2 deletions(-)
diff --git a/drivers/platform/x86/lenovo/thinkpad_acpi.c b/drivers/platform/x86/lenovo/thinkpad_acpi.c
index 8982d92dfd97..b57ae7eb5548 100644
--- a/drivers/platform/x86/lenovo/thinkpad_acpi.c
+++ b/drivers/platform/x86/lenovo/thinkpad_acpi.c
@@ -218,8 +218,9 @@ enum tpacpi_hkey_event_t {
TP_HKEY_EV_LID_OPEN = 0x5002, /* laptop lid opened */
TP_HKEY_EV_TABLET_TABLET = 0x5009, /* tablet swivel up */
TP_HKEY_EV_TABLET_NOTEBOOK = 0x500a, /* tablet swivel down */
- TP_HKEY_EV_TABLET_CHANGED = 0x60c0, /* X1 Yoga (2016):
- * enter/leave tablet mode
+ TP_HKEY_EV_TABLET_CHANGED = 0x60c0, /* posture change event:
+ * X1 Yoga (2016): enter/leave tablet mode
+ * X1 Fold 16 Gen 1: keyboard attachment state changed
*/
TP_HKEY_EV_PEN_INSERTED = 0x500b, /* tablet pen inserted */
TP_HKEY_EV_PEN_REMOVED = 0x500c, /* tablet pen removed */
@@ -375,6 +376,7 @@ static struct {
u32 has_adaptive_kbd:1;
u32 kbd_lang:1;
u32 trackpoint_doubletap:1;
+ u32 has_keyboard_attached_on_screen:1;
struct quirk_entry *quirks;
} tp_features;
@@ -2928,6 +2930,63 @@ static void hotkey_tablet_mode_notify_change(void)
"hotkey_tablet_mode");
}
+static bool keyboard_attached_on_screen;
+static bool keyboard_attached_on_screen_initialized;
+
+static int x1_fold_keyboard_attached_on_screen_get(bool *attached)
+{
+ int state;
+
+ if (!tp_features.has_keyboard_attached_on_screen)
+ return -ENODEV;
+
+ if (!acpi_evalf(NULL, &state, "\\_SB.DEVD.GDST", "d"))
+ return -EIO;
+
+ *attached = state != 0;
+ return 0;
+}
+
+static ssize_t keyboard_attached_on_screen_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ bool attached;
+ int res;
+
+ res = x1_fold_keyboard_attached_on_screen_get(&attached);
+ if (res)
+ return res;
+
+ return sysfs_emit(buf, "%d\n", attached);
+}
+
+static DEVICE_ATTR_RO(keyboard_attached_on_screen);
+
+static void keyboard_attached_on_screen_notify_change(void)
+{
+ if (tp_features.has_keyboard_attached_on_screen)
+ sysfs_notify(&tpacpi_pdev->dev.kobj, NULL,
+ "keyboard_attached_on_screen");
+}
+
+static bool keyboard_attached_on_screen_update(void)
+{
+ bool attached;
+
+ if (x1_fold_keyboard_attached_on_screen_get(&attached))
+ return false;
+
+ if (keyboard_attached_on_screen_initialized &&
+ keyboard_attached_on_screen == attached)
+ return false;
+
+ keyboard_attached_on_screen = attached;
+ keyboard_attached_on_screen_initialized = true;
+
+ return true;
+}
+
/* sysfs wakeup reason (pollable) -------------------------------------- */
static ssize_t hotkey_wakeup_reason_show(struct device *dev,
struct device_attribute *attr,
@@ -3032,6 +3091,7 @@ static struct attribute *hotkey_attributes[] = {
&dev_attr_hotkey_adaptive_all_mask.attr,
&dev_attr_hotkey_recommended_mask.attr,
&dev_attr_hotkey_tablet_mode.attr,
+ &dev_attr_keyboard_attached_on_screen.attr,
&dev_attr_hotkey_radio_sw.attr,
#ifdef CONFIG_THINKPAD_ACPI_HOTKEY_POLL
&dev_attr_hotkey_source_mask.attr,
@@ -3046,6 +3106,9 @@ static umode_t hotkey_attr_is_visible(struct kobject *kobj,
if (attr == &dev_attr_hotkey_tablet_mode.attr) {
if (!tp_features.hotkey_tablet)
return 0;
+ } else if (attr == &dev_attr_keyboard_attached_on_screen.attr) {
+ if (!tp_features.has_keyboard_attached_on_screen)
+ return 0;
} else if (attr == &dev_attr_hotkey_radio_sw.attr) {
if (!tp_features.hotkey_wlsw)
return 0;
@@ -3462,6 +3525,7 @@ static int __init hotkey_init(struct ibm_init_struct *iibm)
}
tabletsw_state = hotkey_init_tablet_mode();
+ keyboard_attached_on_screen_update();
/* Set up key map */
keymap_id = tpacpi_check_quirks(tpacpi_keymap_qtable,
@@ -3842,6 +3906,8 @@ static bool hotkey_notify_6xxx(const u32 hkey, bool *send_acpi_ev)
case TP_HKEY_EV_TABLET_CHANGED:
tpacpi_input_send_tabletsw();
hotkey_tablet_mode_notify_change();
+ if (keyboard_attached_on_screen_update())
+ keyboard_attached_on_screen_notify_change();
*send_acpi_ev = false;
return true;
@@ -3998,6 +4064,8 @@ static void hotkey_resume(void)
tpacpi_send_radiosw_update();
tpacpi_input_send_tabletsw();
hotkey_tablet_mode_notify_change();
+ keyboard_attached_on_screen_update();
+ keyboard_attached_on_screen_notify_change();
hotkey_wakeup_reason_notify_change();
hotkey_wakeup_hotunplug_complete_notify_change();
hotkey_poll_setup_safe(false);
@@ -4296,6 +4364,17 @@ static const struct dmi_system_id fwbug_list[] __initconst = {
{}
};
+static const struct dmi_system_id keyboard_attached_on_screen_list[] __initconst = {
+ {
+ .ident = "ThinkPad X1 Fold 16 Gen 1",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+ DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Fold 16 Gen 1"),
+ },
+ },
+ {}
+};
+
static const struct pci_device_id fwbug_cards_ids[] __initconst = {
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x24F3) },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x24FD) },
@@ -12230,6 +12309,8 @@ static int __init thinkpad_acpi_module_init(void)
dmi_id = dmi_first_match(fwbug_list);
if (dmi_id)
tp_features.quirks = dmi_id->driver_data;
+ tp_features.has_keyboard_attached_on_screen =
+ dmi_check_system(keyboard_attached_on_screen_list);
/* Device initialization */
tpacpi_pdev = platform_device_register_simple(TPACPI_DRVR_NAME, PLATFORM_DEVID_NONE,
--
2.43.0Hi Pit,
On Sun, Apr 19, 2026, at 6:27 AM, Pit Henrich wrote:
> ThinkPad X1 Fold 16 Gen 1 firmware reports whether the keyboard is magnetically
> attached (on the screen), but thinkpad-acpi does not expose this to userspace.
> The state can be obtained via ACPI methods: GDST (get device state).
>
> Add a read-only keyboard_attached_on_screen sysfs attribute, gated by
> a DMI match. The state is read directly from the EC.
>
> Cache the state and emit a sysfs notification on
> TP_HKEY_EV_TABLET_CHANGED (0x60c0) when it changes. Initialize the cache during
> hotkey setup and refresh it before the resume notification to keep the state
> consistent across suspend and resume.
>
> Signed-off-by: Pit Henrich <pithenrich2d@gmail.com>
> ---
> This replaced the v1 patch in:
> https://lore.kernel.org/all/20260314142236.74514-1-pithenrich2d@gmail.com/
>
> Changes v1 -> v2:
> * Use ACPI method instead of using the EC directly (thanks Mark).
>
> ---
> drivers/platform/x86/lenovo/thinkpad_acpi.c | 85 ++++++++++++++++++++-
> 1 file changed, 83 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/platform/x86/lenovo/thinkpad_acpi.c
> b/drivers/platform/x86/lenovo/thinkpad_acpi.c
> index 8982d92dfd97..b57ae7eb5548 100644
> --- a/drivers/platform/x86/lenovo/thinkpad_acpi.c
> +++ b/drivers/platform/x86/lenovo/thinkpad_acpi.c
> @@ -218,8 +218,9 @@ enum tpacpi_hkey_event_t {
> TP_HKEY_EV_LID_OPEN = 0x5002, /* laptop lid opened */
> TP_HKEY_EV_TABLET_TABLET = 0x5009, /* tablet swivel up */
> TP_HKEY_EV_TABLET_NOTEBOOK = 0x500a, /* tablet swivel down */
> - TP_HKEY_EV_TABLET_CHANGED = 0x60c0, /* X1 Yoga (2016):
> - * enter/leave tablet mode
> + TP_HKEY_EV_TABLET_CHANGED = 0x60c0, /* posture change event:
> + * X1 Yoga (2016): enter/leave tablet mode
> + * X1 Fold 16 Gen 1: keyboard attachment state changed
> */
> TP_HKEY_EV_PEN_INSERTED = 0x500b, /* tablet pen inserted */
> TP_HKEY_EV_PEN_REMOVED = 0x500c, /* tablet pen removed */
> @@ -375,6 +376,7 @@ static struct {
> u32 has_adaptive_kbd:1;
> u32 kbd_lang:1;
> u32 trackpoint_doubletap:1;
> + u32 has_keyboard_attached_on_screen:1;
> struct quirk_entry *quirks;
> } tp_features;
>
> @@ -2928,6 +2930,63 @@ static void hotkey_tablet_mode_notify_change(void)
> "hotkey_tablet_mode");
> }
>
> +static bool keyboard_attached_on_screen;
> +static bool keyboard_attached_on_screen_initialized;
> +
> +static int x1_fold_keyboard_attached_on_screen_get(bool *attached)
> +{
> + int state;
> +
> + if (!tp_features.has_keyboard_attached_on_screen)
> + return -ENODEV;
> +
> + if (!acpi_evalf(NULL, &state, "\\_SB.DEVD.GDST", "d"))
> + return -EIO;
I wondered if this should be adding a devd_handle in the same way as hkey_handle etc? (up at the top of the file using define TPACPI_HANDLE
Then you would have
if (!acpi_evalf(devd_handle, &state, "GDST", "d"))
Not sure if this is needed or not - hopefully one of the experts on the mailing list knows.
> +
> + *attached = state != 0;
> + return 0;
> +}
> +
> +static ssize_t keyboard_attached_on_screen_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + bool attached;
> + int res;
> +
> + res = x1_fold_keyboard_attached_on_screen_get(&attached);
> + if (res)
> + return res;
> +
> + return sysfs_emit(buf, "%d\n", attached);
> +}
> +
> +static DEVICE_ATTR_RO(keyboard_attached_on_screen);
> +
> +static void keyboard_attached_on_screen_notify_change(void)
> +{
> + if (tp_features.has_keyboard_attached_on_screen)
> + sysfs_notify(&tpacpi_pdev->dev.kobj, NULL,
> + "keyboard_attached_on_screen");
> +}
> +
> +static bool keyboard_attached_on_screen_update(void)
> +{
> + bool attached;
> +
> + if (x1_fold_keyboard_attached_on_screen_get(&attached))
> + return false;
> +
> + if (keyboard_attached_on_screen_initialized &&
> + keyboard_attached_on_screen == attached)
> + return false;
> +
> + keyboard_attached_on_screen = attached;
> + keyboard_attached_on_screen_initialized = true;
> +
> + return true;
> +}
> +
> /* sysfs wakeup reason (pollable)
> -------------------------------------- */
> static ssize_t hotkey_wakeup_reason_show(struct device *dev,
> struct device_attribute *attr,
> @@ -3032,6 +3091,7 @@ static struct attribute *hotkey_attributes[] = {
> &dev_attr_hotkey_adaptive_all_mask.attr,
> &dev_attr_hotkey_recommended_mask.attr,
> &dev_attr_hotkey_tablet_mode.attr,
> + &dev_attr_keyboard_attached_on_screen.attr,
> &dev_attr_hotkey_radio_sw.attr,
> #ifdef CONFIG_THINKPAD_ACPI_HOTKEY_POLL
> &dev_attr_hotkey_source_mask.attr,
> @@ -3046,6 +3106,9 @@ static umode_t hotkey_attr_is_visible(struct
> kobject *kobj,
> if (attr == &dev_attr_hotkey_tablet_mode.attr) {
> if (!tp_features.hotkey_tablet)
> return 0;
> + } else if (attr == &dev_attr_keyboard_attached_on_screen.attr) {
> + if (!tp_features.has_keyboard_attached_on_screen)
> + return 0;
> } else if (attr == &dev_attr_hotkey_radio_sw.attr) {
> if (!tp_features.hotkey_wlsw)
> return 0;
> @@ -3462,6 +3525,7 @@ static int __init hotkey_init(struct
> ibm_init_struct *iibm)
> }
>
> tabletsw_state = hotkey_init_tablet_mode();
> + keyboard_attached_on_screen_update();
>
> /* Set up key map */
> keymap_id = tpacpi_check_quirks(tpacpi_keymap_qtable,
> @@ -3842,6 +3906,8 @@ static bool hotkey_notify_6xxx(const u32 hkey,
> bool *send_acpi_ev)
> case TP_HKEY_EV_TABLET_CHANGED:
> tpacpi_input_send_tabletsw();
> hotkey_tablet_mode_notify_change();
> + if (keyboard_attached_on_screen_update())
> + keyboard_attached_on_screen_notify_change();
> *send_acpi_ev = false;
> return true;
>
> @@ -3998,6 +4064,8 @@ static void hotkey_resume(void)
> tpacpi_send_radiosw_update();
> tpacpi_input_send_tabletsw();
> hotkey_tablet_mode_notify_change();
> + keyboard_attached_on_screen_update();
> + keyboard_attached_on_screen_notify_change();
> hotkey_wakeup_reason_notify_change();
> hotkey_wakeup_hotunplug_complete_notify_change();
> hotkey_poll_setup_safe(false);
> @@ -4296,6 +4364,17 @@ static const struct dmi_system_id fwbug_list[]
> __initconst = {
> {}
> };
>
> +static const struct dmi_system_id keyboard_attached_on_screen_list[]
> __initconst = {
> + {
> + .ident = "ThinkPad X1 Fold 16 Gen 1",
> + .matches = {
> + DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
> + DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Fold 16 Gen 1"),
> + },
Should there also be a matches for the X1 Fold Gen 1 (13" model)?
I think doing the DMI match on the product family is OK, but just a note that everywhere else uses the board ID. e.g: DMI_MATCH(DMI_BOARD_NAME, "21ES")
I think this way works too, but it's different and I haven't had confirmation from the FW team if it could be different across different SKUs (I'll see if I can find out).
If you do want to use board names:
- X1 Fold 16 G1 has "21ES' and "21ET"
- X1 Fold G1 has "20RK" and "20RL"
> + },
> + {}
> +};
> +
> static const struct pci_device_id fwbug_cards_ids[] __initconst = {
> { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x24F3) },
> { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x24FD) },
> @@ -12230,6 +12309,8 @@ static int __init
> thinkpad_acpi_module_init(void)
> dmi_id = dmi_first_match(fwbug_list);
> if (dmi_id)
> tp_features.quirks = dmi_id->driver_data;
> + tp_features.has_keyboard_attached_on_screen =
> + dmi_check_system(keyboard_attached_on_screen_list);
>
> /* Device initialization */
> tpacpi_pdev = platform_device_register_simple(TPACPI_DRVR_NAME,
> PLATFORM_DEVID_NONE,
> --
> 2.43.0
Thanks
Mark
Hi,
On 9-Jun-26 03:19, Mark Pearson wrote:
> Hi Pit,
>
> On Sun, Apr 19, 2026, at 6:27 AM, Pit Henrich wrote:
>> ThinkPad X1 Fold 16 Gen 1 firmware reports whether the keyboard is magnetically
>> attached (on the screen), but thinkpad-acpi does not expose this to userspace.
>> The state can be obtained via ACPI methods: GDST (get device state).
>>
>> Add a read-only keyboard_attached_on_screen sysfs attribute, gated by
>> a DMI match. The state is read directly from the EC.
>>
>> Cache the state and emit a sysfs notification on
>> TP_HKEY_EV_TABLET_CHANGED (0x60c0) when it changes. Initialize the cache during
>> hotkey setup and refresh it before the resume notification to keep the state
>> consistent across suspend and resume.
>>
>> Signed-off-by: Pit Henrich <pithenrich2d@gmail.com>
>> ---
>> This replaced the v1 patch in:
>> https://lore.kernel.org/all/20260314142236.74514-1-pithenrich2d@gmail.com/
>>
>> Changes v1 -> v2:
>> * Use ACPI method instead of using the EC directly (thanks Mark).
>>
>> ---
>> drivers/platform/x86/lenovo/thinkpad_acpi.c | 85 ++++++++++++++++++++-
>> 1 file changed, 83 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/platform/x86/lenovo/thinkpad_acpi.c
>> b/drivers/platform/x86/lenovo/thinkpad_acpi.c
>> index 8982d92dfd97..b57ae7eb5548 100644
>> --- a/drivers/platform/x86/lenovo/thinkpad_acpi.c
>> +++ b/drivers/platform/x86/lenovo/thinkpad_acpi.c
>> @@ -218,8 +218,9 @@ enum tpacpi_hkey_event_t {
>> TP_HKEY_EV_LID_OPEN = 0x5002, /* laptop lid opened */
>> TP_HKEY_EV_TABLET_TABLET = 0x5009, /* tablet swivel up */
>> TP_HKEY_EV_TABLET_NOTEBOOK = 0x500a, /* tablet swivel down */
>> - TP_HKEY_EV_TABLET_CHANGED = 0x60c0, /* X1 Yoga (2016):
>> - * enter/leave tablet mode
>> + TP_HKEY_EV_TABLET_CHANGED = 0x60c0, /* posture change event:
>> + * X1 Yoga (2016): enter/leave tablet mode
>> + * X1 Fold 16 Gen 1: keyboard attachment state changed
>> */
>> TP_HKEY_EV_PEN_INSERTED = 0x500b, /* tablet pen inserted */
>> TP_HKEY_EV_PEN_REMOVED = 0x500c, /* tablet pen removed */
>> @@ -375,6 +376,7 @@ static struct {
>> u32 has_adaptive_kbd:1;
>> u32 kbd_lang:1;
>> u32 trackpoint_doubletap:1;
>> + u32 has_keyboard_attached_on_screen:1;
>> struct quirk_entry *quirks;
>> } tp_features;
>>
>> @@ -2928,6 +2930,63 @@ static void hotkey_tablet_mode_notify_change(void)
>> "hotkey_tablet_mode");
>> }
>>
>> +static bool keyboard_attached_on_screen;
>> +static bool keyboard_attached_on_screen_initialized;
>> +
>> +static int x1_fold_keyboard_attached_on_screen_get(bool *attached)
>> +{
>> + int state;
>> +
>> + if (!tp_features.has_keyboard_attached_on_screen)
>> + return -ENODEV;
>> +
>> + if (!acpi_evalf(NULL, &state, "\\_SB.DEVD.GDST", "d"))
>> + return -EIO;
>
> I wondered if this should be adding a devd_handle in the same way as hkey_handle etc? (up at the top of the file using define TPACPI_HANDLE
>
> Then you would have
> if (!acpi_evalf(devd_handle, &state, "GDST", "d"))
>
> Not sure if this is needed or not - hopefully one of the experts on the mailing list knows.
I don't think using a cached ACPI handle for the parent node
of the method is necessary in this case.
Using the cached handles is mostly an optimization for
handles which are used a lot.
Regards,
Hans
>
>> +
>> + *attached = state != 0;
>> + return 0;
>> +}
>> +
>> +static ssize_t keyboard_attached_on_screen_show(struct device *dev,
>> + struct device_attribute *attr,
>> + char *buf)
>> +{
>> + bool attached;
>> + int res;
>> +
>> + res = x1_fold_keyboard_attached_on_screen_get(&attached);
>> + if (res)
>> + return res;
>> +
>> + return sysfs_emit(buf, "%d\n", attached);
>> +}
>> +
>> +static DEVICE_ATTR_RO(keyboard_attached_on_screen);
>> +
>> +static void keyboard_attached_on_screen_notify_change(void)
>> +{
>> + if (tp_features.has_keyboard_attached_on_screen)
>> + sysfs_notify(&tpacpi_pdev->dev.kobj, NULL,
>> + "keyboard_attached_on_screen");
>> +}
>> +
>> +static bool keyboard_attached_on_screen_update(void)
>> +{
>> + bool attached;
>> +
>> + if (x1_fold_keyboard_attached_on_screen_get(&attached))
>> + return false;
>> +
>> + if (keyboard_attached_on_screen_initialized &&
>> + keyboard_attached_on_screen == attached)
>> + return false;
>> +
>> + keyboard_attached_on_screen = attached;
>> + keyboard_attached_on_screen_initialized = true;
>> +
>> + return true;
>> +}
>> +
>> /* sysfs wakeup reason (pollable)
>> -------------------------------------- */
>> static ssize_t hotkey_wakeup_reason_show(struct device *dev,
>> struct device_attribute *attr,
>> @@ -3032,6 +3091,7 @@ static struct attribute *hotkey_attributes[] = {
>> &dev_attr_hotkey_adaptive_all_mask.attr,
>> &dev_attr_hotkey_recommended_mask.attr,
>> &dev_attr_hotkey_tablet_mode.attr,
>> + &dev_attr_keyboard_attached_on_screen.attr,
>> &dev_attr_hotkey_radio_sw.attr,
>> #ifdef CONFIG_THINKPAD_ACPI_HOTKEY_POLL
>> &dev_attr_hotkey_source_mask.attr,
>> @@ -3046,6 +3106,9 @@ static umode_t hotkey_attr_is_visible(struct
>> kobject *kobj,
>> if (attr == &dev_attr_hotkey_tablet_mode.attr) {
>> if (!tp_features.hotkey_tablet)
>> return 0;
>> + } else if (attr == &dev_attr_keyboard_attached_on_screen.attr) {
>> + if (!tp_features.has_keyboard_attached_on_screen)
>> + return 0;
>> } else if (attr == &dev_attr_hotkey_radio_sw.attr) {
>> if (!tp_features.hotkey_wlsw)
>> return 0;
>> @@ -3462,6 +3525,7 @@ static int __init hotkey_init(struct
>> ibm_init_struct *iibm)
>> }
>>
>> tabletsw_state = hotkey_init_tablet_mode();
>> + keyboard_attached_on_screen_update();
>>
>> /* Set up key map */
>> keymap_id = tpacpi_check_quirks(tpacpi_keymap_qtable,
>> @@ -3842,6 +3906,8 @@ static bool hotkey_notify_6xxx(const u32 hkey,
>> bool *send_acpi_ev)
>> case TP_HKEY_EV_TABLET_CHANGED:
>> tpacpi_input_send_tabletsw();
>> hotkey_tablet_mode_notify_change();
>> + if (keyboard_attached_on_screen_update())
>> + keyboard_attached_on_screen_notify_change();
>> *send_acpi_ev = false;
>> return true;
>>
>> @@ -3998,6 +4064,8 @@ static void hotkey_resume(void)
>> tpacpi_send_radiosw_update();
>> tpacpi_input_send_tabletsw();
>> hotkey_tablet_mode_notify_change();
>> + keyboard_attached_on_screen_update();
>> + keyboard_attached_on_screen_notify_change();
>> hotkey_wakeup_reason_notify_change();
>> hotkey_wakeup_hotunplug_complete_notify_change();
>> hotkey_poll_setup_safe(false);
>> @@ -4296,6 +4364,17 @@ static const struct dmi_system_id fwbug_list[]
>> __initconst = {
>> {}
>> };
>>
>> +static const struct dmi_system_id keyboard_attached_on_screen_list[]
>> __initconst = {
>> + {
>> + .ident = "ThinkPad X1 Fold 16 Gen 1",
>> + .matches = {
>> + DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
>> + DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Fold 16 Gen 1"),
>> + },
>
> Should there also be a matches for the X1 Fold Gen 1 (13" model)?
>
> I think doing the DMI match on the product family is OK, but just a note that everywhere else uses the board ID. e.g: DMI_MATCH(DMI_BOARD_NAME, "21ES")
> I think this way works too, but it's different and I haven't had confirmation from the FW team if it could be different across different SKUs (I'll see if I can find out).
>
> If you do want to use board names:
> - X1 Fold 16 G1 has "21ES' and "21ET"
> - X1 Fold G1 has "20RK" and "20RL"
>
>> + },
>> + {}
>> +};
>> +
>> static const struct pci_device_id fwbug_cards_ids[] __initconst = {
>> { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x24F3) },
>> { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x24FD) },
>> @@ -12230,6 +12309,8 @@ static int __init
>> thinkpad_acpi_module_init(void)
>> dmi_id = dmi_first_match(fwbug_list);
>> if (dmi_id)
>> tp_features.quirks = dmi_id->driver_data;
>> + tp_features.has_keyboard_attached_on_screen =
>> + dmi_check_system(keyboard_attached_on_screen_list);
>>
>> /* Device initialization */
>> tpacpi_pdev = platform_device_register_simple(TPACPI_DRVR_NAME,
>> PLATFORM_DEVID_NONE,
>> --
>> 2.43.0
>
> Thanks
> Mark
Hi,
On 19-Apr-26 12:27 PM, Pit Henrich wrote:
> ThinkPad X1 Fold 16 Gen 1 firmware reports whether the keyboard is magnetically
> attached (on the screen), but thinkpad-acpi does not expose this to userspace.
> The state can be obtained via ACPI methods: GDST (get device state).
>
> Add a read-only keyboard_attached_on_screen sysfs attribute, gated by
> a DMI match. The state is read directly from the EC.
>
> Cache the state and emit a sysfs notification on
> TP_HKEY_EV_TABLET_CHANGED (0x60c0) when it changes. Initialize the cache during
> hotkey setup and refresh it before the resume notification to keep the state
> consistent across suspend and resume.
>
> Signed-off-by: Pit Henrich <pithenrich2d@gmail.com>
> ---
> This replaced the v1 patch in:
> https://lore.kernel.org/all/20260314142236.74514-1-pithenrich2d@gmail.com/
>
> Changes v1 -> v2:
> * Use ACPI method instead of using the EC directly (thanks Mark).
Thank you for your patch. It seems that this information is also exposed
via WMI and a WMI driver exposing the same information is also being
worked on:
https://patchwork.kernel.org/project/platform-driver-x86/patch/20260527122701.242907-1-carvsdriver@gmail.com/
+Cc Dave Carey (author of that driver) and Armin (WMI maintainer)
Since doing this in thinkpad_acpi requires adding a DMI match and
directly calling an APCI method which name may change I believe that
the WMI approach may be better. There we can rely on only the Fold exposing
the WMI GUID for this functionality.
Dave, I see that your "[PATCH v5] platform/x86/lenovo: Add Yoga Book 9 keyboard
dock detection driver" patch also uses a DMI match, is that necessary ?
If we need the DMI match because the GUID is not unique enough, then we might
just as well add this functionality here as this patch is doing ...
I do wonder since this seems to emit TP_HKEY_EV_TABLET_CHANGED thinkpad_acpi
events if the existing thinkpad_acpi support does not already provide working
SW_TABLET_MODE input ?
If it does then also having the WMI driver emit SW_TABLET_MODE events seems
to be undesirable duplicate functionality.
Regards,
Hans
>
> ---
> drivers/platform/x86/lenovo/thinkpad_acpi.c | 85 ++++++++++++++++++++-
> 1 file changed, 83 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/platform/x86/lenovo/thinkpad_acpi.c b/drivers/platform/x86/lenovo/thinkpad_acpi.c
> index 8982d92dfd97..b57ae7eb5548 100644
> --- a/drivers/platform/x86/lenovo/thinkpad_acpi.c
> +++ b/drivers/platform/x86/lenovo/thinkpad_acpi.c
> @@ -218,8 +218,9 @@ enum tpacpi_hkey_event_t {
> TP_HKEY_EV_LID_OPEN = 0x5002, /* laptop lid opened */
> TP_HKEY_EV_TABLET_TABLET = 0x5009, /* tablet swivel up */
> TP_HKEY_EV_TABLET_NOTEBOOK = 0x500a, /* tablet swivel down */
> - TP_HKEY_EV_TABLET_CHANGED = 0x60c0, /* X1 Yoga (2016):
> - * enter/leave tablet mode
> + TP_HKEY_EV_TABLET_CHANGED = 0x60c0, /* posture change event:
> + * X1 Yoga (2016): enter/leave tablet mode
> + * X1 Fold 16 Gen 1: keyboard attachment state changed
> */
> TP_HKEY_EV_PEN_INSERTED = 0x500b, /* tablet pen inserted */
> TP_HKEY_EV_PEN_REMOVED = 0x500c, /* tablet pen removed */
> @@ -375,6 +376,7 @@ static struct {
> u32 has_adaptive_kbd:1;
> u32 kbd_lang:1;
> u32 trackpoint_doubletap:1;
> + u32 has_keyboard_attached_on_screen:1;
> struct quirk_entry *quirks;
> } tp_features;
>
> @@ -2928,6 +2930,63 @@ static void hotkey_tablet_mode_notify_change(void)
> "hotkey_tablet_mode");
> }
>
> +static bool keyboard_attached_on_screen;
> +static bool keyboard_attached_on_screen_initialized;
> +
> +static int x1_fold_keyboard_attached_on_screen_get(bool *attached)
> +{
> + int state;
> +
> + if (!tp_features.has_keyboard_attached_on_screen)
> + return -ENODEV;
> +
> + if (!acpi_evalf(NULL, &state, "\\_SB.DEVD.GDST", "d"))
> + return -EIO;
> +
> + *attached = state != 0;
> + return 0;
> +}
> +
> +static ssize_t keyboard_attached_on_screen_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + bool attached;
> + int res;
> +
> + res = x1_fold_keyboard_attached_on_screen_get(&attached);
> + if (res)
> + return res;
> +
> + return sysfs_emit(buf, "%d\n", attached);
> +}
> +
> +static DEVICE_ATTR_RO(keyboard_attached_on_screen);
> +
> +static void keyboard_attached_on_screen_notify_change(void)
> +{
> + if (tp_features.has_keyboard_attached_on_screen)
> + sysfs_notify(&tpacpi_pdev->dev.kobj, NULL,
> + "keyboard_attached_on_screen");
> +}
> +
> +static bool keyboard_attached_on_screen_update(void)
> +{
> + bool attached;
> +
> + if (x1_fold_keyboard_attached_on_screen_get(&attached))
> + return false;
> +
> + if (keyboard_attached_on_screen_initialized &&
> + keyboard_attached_on_screen == attached)
> + return false;
> +
> + keyboard_attached_on_screen = attached;
> + keyboard_attached_on_screen_initialized = true;
> +
> + return true;
> +}
> +
> /* sysfs wakeup reason (pollable) -------------------------------------- */
> static ssize_t hotkey_wakeup_reason_show(struct device *dev,
> struct device_attribute *attr,
> @@ -3032,6 +3091,7 @@ static struct attribute *hotkey_attributes[] = {
> &dev_attr_hotkey_adaptive_all_mask.attr,
> &dev_attr_hotkey_recommended_mask.attr,
> &dev_attr_hotkey_tablet_mode.attr,
> + &dev_attr_keyboard_attached_on_screen.attr,
> &dev_attr_hotkey_radio_sw.attr,
> #ifdef CONFIG_THINKPAD_ACPI_HOTKEY_POLL
> &dev_attr_hotkey_source_mask.attr,
> @@ -3046,6 +3106,9 @@ static umode_t hotkey_attr_is_visible(struct kobject *kobj,
> if (attr == &dev_attr_hotkey_tablet_mode.attr) {
> if (!tp_features.hotkey_tablet)
> return 0;
> + } else if (attr == &dev_attr_keyboard_attached_on_screen.attr) {
> + if (!tp_features.has_keyboard_attached_on_screen)
> + return 0;
> } else if (attr == &dev_attr_hotkey_radio_sw.attr) {
> if (!tp_features.hotkey_wlsw)
> return 0;
> @@ -3462,6 +3525,7 @@ static int __init hotkey_init(struct ibm_init_struct *iibm)
> }
>
> tabletsw_state = hotkey_init_tablet_mode();
> + keyboard_attached_on_screen_update();
>
> /* Set up key map */
> keymap_id = tpacpi_check_quirks(tpacpi_keymap_qtable,
> @@ -3842,6 +3906,8 @@ static bool hotkey_notify_6xxx(const u32 hkey, bool *send_acpi_ev)
> case TP_HKEY_EV_TABLET_CHANGED:
> tpacpi_input_send_tabletsw();
> hotkey_tablet_mode_notify_change();
> + if (keyboard_attached_on_screen_update())
> + keyboard_attached_on_screen_notify_change();
> *send_acpi_ev = false;
> return true;
>
> @@ -3998,6 +4064,8 @@ static void hotkey_resume(void)
> tpacpi_send_radiosw_update();
> tpacpi_input_send_tabletsw();
> hotkey_tablet_mode_notify_change();
> + keyboard_attached_on_screen_update();
> + keyboard_attached_on_screen_notify_change();
> hotkey_wakeup_reason_notify_change();
> hotkey_wakeup_hotunplug_complete_notify_change();
> hotkey_poll_setup_safe(false);
> @@ -4296,6 +4364,17 @@ static const struct dmi_system_id fwbug_list[] __initconst = {
> {}
> };
>
> +static const struct dmi_system_id keyboard_attached_on_screen_list[] __initconst = {
> + {
> + .ident = "ThinkPad X1 Fold 16 Gen 1",
> + .matches = {
> + DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
> + DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Fold 16 Gen 1"),
> + },
> + },
> + {}
> +};
> +
> static const struct pci_device_id fwbug_cards_ids[] __initconst = {
> { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x24F3) },
> { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x24FD) },
> @@ -12230,6 +12309,8 @@ static int __init thinkpad_acpi_module_init(void)
> dmi_id = dmi_first_match(fwbug_list);
> if (dmi_id)
> tp_features.quirks = dmi_id->driver_data;
> + tp_features.has_keyboard_attached_on_screen =
> + dmi_check_system(keyboard_attached_on_screen_list);
>
> /* Device initialization */
> tpacpi_pdev = platform_device_register_simple(TPACPI_DRVR_NAME, PLATFORM_DEVID_NONE,
Hi, On 8-Jun-26 11:09, Hans de Goede wrote: > Hi, > > On 19-Apr-26 12:27 PM, Pit Henrich wrote: >> ThinkPad X1 Fold 16 Gen 1 firmware reports whether the keyboard is magnetically >> attached (on the screen), but thinkpad-acpi does not expose this to userspace. >> The state can be obtained via ACPI methods: GDST (get device state). >> >> Add a read-only keyboard_attached_on_screen sysfs attribute, gated by >> a DMI match. The state is read directly from the EC. >> >> Cache the state and emit a sysfs notification on >> TP_HKEY_EV_TABLET_CHANGED (0x60c0) when it changes. Initialize the cache during >> hotkey setup and refresh it before the resume notification to keep the state >> consistent across suspend and resume. >> >> Signed-off-by: Pit Henrich <pithenrich2d@gmail.com> >> --- >> This replaced the v1 patch in: >> https://lore.kernel.org/all/20260314142236.74514-1-pithenrich2d@gmail.com/ >> >> Changes v1 -> v2: >> * Use ACPI method instead of using the EC directly (thanks Mark). > > Thank you for your patch. It seems that this information is also exposed > via WMI and a WMI driver exposing the same information is also being > worked on: > > https://patchwork.kernel.org/project/platform-driver-x86/patch/20260527122701.242907-1-carvsdriver@gmail.com/ > > +Cc Dave Carey (author of that driver) and Armin (WMI maintainer) Ok, I should have looked closer, this patch is for a "ThinkPad X1 Fold 16 Gen 1" and the driver I linked above is for a "Yoga Book 9" so I was mistaken that these drivers are duplicate, we will need both. Sorry, my bad. Note not a full review, but before we can move forward with this driver, you are going to need to document the new sysfs attribute under: Documentation/admin-guide/laptops/thinkpad-acpi.rst Please add a new "X1 Fold keyboard attachmen" section directly after the "Hardware damage detection capability" section (or iow just above the "Multiple Commands, Module Parameters" section). Regards, Hans
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