[PATCH 18/26] ACPI: thinkpad-acpi: add tablet-mode reporting

Len Brown
2008-02-21T09:29:16Z

From: Henrique de Moraes Holschuh <hmh@hmh.eng.br>

A quick study of the 0x5009/0x500A HKEY event on the X61t DSDT revealed the
existence of the EC HTAB register (EC 0x0f, bit 7), and a compare with the
X41t DSDT shows that HKEY.MHKG can be used to verify if the ThinkPad is
tablet-capable (MHKG present), and in tablet mode (bit 3 of MHKG return is
set).

Add an attribute to report this information, "hotkey_tablet_mode". This
attribute has poll()/select() support, and can be used along with EV_SW
SW_TABLET_MODE to hook userspace to tablet events.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Len Brown <len.brown@intel.com>
---
Documentation/laptops/thinkpad-acpi.txt | 7 +++
drivers/misc/thinkpad_acpi.c | 79 ++++++++++++++++++++++++++----
2 files changed, 75 insertions(+), 11 deletions(-)

diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt
index 606af16..76cb428 100644
--- a/Documentation/laptops/thinkpad-acpi.txt
+++ b/Documentation/laptops/thinkpad-acpi.txt
@@ -313,6 +313,13 @@ sysfs notes:

This attribute has poll()/select() support.

+ hotkey_tablet_mode:
+ If the ThinkPad has tablet capabilities, this attribute
+ will read 0 if the ThinkPad is in normal mode, and
+ 1 if the ThinkPad is in tablet mode.
+
+ This attribute has poll()/select() support.
+
hotkey_report_mode:
Returns the state of the procfs ACPI event report mode
filter for hot keys. If it is set to 1 (the default),
diff --git a/drivers/misc/thinkpad_acpi.c b/drivers/misc/thinkpad_acpi.c
index c119cf2..bb269d0 100644
--- a/drivers/misc/thinkpad_acpi.c
+++ b/drivers/misc/thinkpad_acpi.c
@@ -221,6 +221,7 @@ static struct {
u32 hotkey:1;
u32 hotkey_mask:1;
u32 hotkey_wlsw:1;
+ u32 hotkey_tablet:1;
u32 light:1;
u32 light_status:1;
u32 bright_16levels:1;
@@ -1060,6 +1061,9 @@ static struct attribute_set *hotkey_dev_attributes;
#define HOTKEY_CONFIG_CRITICAL_END
#endif /* CONFIG_THINKPAD_ACPI_HOTKEY_POLL */

+/* HKEY.MHKG() return bits */
+#define TP_HOTKEY_TABLET_MASK (1 << 3)
+
static int hotkey_get_wlsw(int *status)
{
if (!acpi_evalf(hkey_handle, status, "WLSW", "d"))
@@ -1067,6 +1071,16 @@ static int hotkey_get_wlsw(int *status)
return 0;
}

+static int hotkey_get_tablet_mode(int *status)
+{
+ int s;
+
+ if (!acpi_evalf(hkey_handle, &s, "MHKG", "d"))
+ return -EIO;
+
+ return ((s & TP_HOTKEY_TABLET_MASK) != 0);
+}
+
/*
* Call with hotkey_mutex held
*/
@@ -1172,15 +1186,20 @@ static void tpacpi_input_send_radiosw(void)
}
}

-static void tpacpi_input_send_tabletsw(unsigned int state)
+static void tpacpi_input_send_tabletsw(void)
{
- mutex_lock(&tpacpi_inputdev_send_mutex);
+ int state;

- input_report_switch(tpacpi_inputdev,
- SW_TABLET_MODE, !!state);
- input_sync(tpacpi_inputdev);
+ if (tp_features.hotkey_tablet &&
+ !hotkey_get_tablet_mode(&state)) {
+ mutex_lock(&tpacpi_inputdev_send_mutex);

- mutex_unlock(&tpacpi_inputdev_send_mutex);
+ input_report_switch(tpacpi_inputdev,
+ SW_TABLET_MODE, !!state);
+ input_sync(tpacpi_inputdev);
+
+ mutex_unlock(&tpacpi_inputdev_send_mutex);
+ }
}

static void tpacpi_input_send_key(unsigned int scancode)
@@ -1691,6 +1710,29 @@ static void hotkey_radio_sw_notify_change(void)
"hotkey_radio_sw");
}

+/* sysfs hotkey tablet mode (pollable) --------------------------------- */
+static ssize_t hotkey_tablet_mode_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ int res, s;
+ res = hotkey_get_tablet_mode(&s);
+ if (res < 0)
+ return res;
+
+ return snprintf(buf, PAGE_SIZE, "%d\n", !!s);
+}
+
+static struct device_attribute dev_attr_hotkey_tablet_mode =
+ __ATTR(hotkey_tablet_mode, S_IRUGO, hotkey_tablet_mode_show, NULL);
+
+static void hotkey_tablet_mode_notify_change(void)
+{
+ if (tp_features.hotkey_tablet)
+ sysfs_notify(&tpacpi_pdev->dev.kobj, NULL,
+ "hotkey_tablet_mode");
+}
+
/* sysfs hotkey report_mode -------------------------------------------- */
static ssize_t hotkey_report_mode_show(struct device *dev,
struct device_attribute *attr,
@@ -1903,7 +1945,7 @@ static int __init hotkey_init(struct ibm_init_struct *iibm)
str_supported(tp_features.hotkey));

if (tp_features.hotkey) {
- hotkey_dev_attributes = create_attr_set(12, NULL);
+ hotkey_dev_attributes = create_attr_set(13, NULL);
if (!hotkey_dev_attributes)
return -ENOMEM;
res = add_many_to_attr_set(hotkey_dev_attributes,
@@ -1982,6 +2024,18 @@ static int __init hotkey_init(struct ibm_init_struct *iibm)
&dev_attr_hotkey_radio_sw.attr);
}

+ /* For X41t, X60t, X61t Tablets... */
+ if (!res && acpi_evalf(hkey_handle, &status, "MHKG", "qd")) {
+ tp_features.hotkey_tablet = 1;
+ printk(TPACPI_INFO
+ "possible tablet mode switch found; "
+ "ThinkPad in %s mode\n",
+ (status & TP_HOTKEY_TABLET_MASK)?
+ "tablet" : "laptop");
+ res = add_to_attr_set(hotkey_dev_attributes,
+ &dev_attr_hotkey_tablet_mode.attr);
+ }
+
if (!res)
res = register_attr_set_with_sysfs(
hotkey_dev_attributes,
@@ -2031,7 +2085,7 @@ static int __init hotkey_init(struct ibm_init_struct *iibm)
set_bit(EV_SW, tpacpi_inputdev->evbit);
set_bit(SW_RADIO, tpacpi_inputdev->swbit);
}
- if (thinkpad_id.vendor == PCI_VENDOR_ID_LENOVO) {
+ if (tp_features.hotkey_tablet) {
set_bit(EV_SW, tpacpi_inputdev->evbit);
set_bit(SW_TABLET_MODE, tpacpi_inputdev->swbit);
}
@@ -2057,6 +2111,7 @@ static int __init hotkey_init(struct ibm_init_struct *iibm)

hotkey_poll_setup_safe(1);
tpacpi_input_send_radiosw();
+ tpacpi_input_send_tabletsw();
}

return (tp_features.hotkey)? 0 : 1;
@@ -2187,9 +2242,10 @@ static void hotkey_notify(struct ibm_struct *ibm, u32 event)
case 0x500b: /* X61t: tablet pen inserted into bay */
case 0x500c: /* X61t: tablet pen removed from bay */
break;
- case 0x5009: /* X61t: swivel up (tablet mode) */
- case 0x500a: /* X61t: swivel down (normal mode) */
- tpacpi_input_send_tabletsw((hkey == 0x5009));
+ case 0x5009: /* X41t-X61t: swivel up (tablet mode) */
+ case 0x500a: /* X41t-X61t: swivel down (normal mode) */
+ tpacpi_input_send_tabletsw();
+ hotkey_tablet_mode_notify_change();
send_acpi_ev = 0;
break;
case 0x5001:
@@ -2250,6 +2306,7 @@ static void hotkey_resume(void)
"from firmware\n");
tpacpi_input_send_radiosw();
hotkey_radio_sw_notify_change();
+ hotkey_tablet_mode_notify_change();
hotkey_wakeup_reason_notify_change();
hotkey_wakeup_hotunplug_complete_notify_change();
hotkey_poll_setup_safe(0);
--
1.5.4.2