[PATCH 5.16 099/285] platform/x86: hp-wmi: Fix SW_TABLET_MODE detection method

Greg Kroah-Hartman
2022-04-12T07:45:53Z

From: Jorge Lopez <jorge.lopez2@hp.com>

[ Upstream commit 520ee4ea1cc60251a6e3c911cf0336278aa52634 ]

The purpose of this patch is to introduce a fix and removal of the
current hack when determining tablet mode status.

Determining the tablet mode status requires reading Byte 0 bit 2 as
reported by HPWMI_HARDWARE_QUERY. The investigation identified the
failure was rooted in two areas: HPWMI_HARDWARE_QUERY failure (0x05)
and reading Byte 0, bit 2 only to determine the table mode status.
HPWMI_HARDWARE_QUERY WMI failure also rendered the dock state value
invalid.

The latest changes use SMBIOS Type 3 (chassis type) and WMI Command
0x40 (device_mode_status) information to determine if the device is
in tablet mode or not.

hp_wmi_hw_state function was split into two functions;
hp_wmi_get_dock_state and hp_wmi_get_tablet_mode. The new functions
separate how dock_state and tablet_mode is handled in a cleaner
manner.

All changes were validated on a HP ZBook Workstation notebook,
HP EliteBook x360, and HP EliteBook 850 G8.

Signed-off-by: Jorge Lopez <jorge.lopez2@hp.com>
Link: https://lore.kernel.org/r/20220310210853.28367-3-jorge.lopez2@hp.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/platform/x86/hp-wmi.c | 71 +++++++++++++++++++++++++----------
1 file changed, 52 insertions(+), 19 deletions(-)

diff --git a/drivers/platform/x86/hp-wmi.c b/drivers/platform/x86/hp-wmi.c
index 48a46466f086..f822ef6eb93c 100644
--- a/drivers/platform/x86/hp-wmi.c
+++ b/drivers/platform/x86/hp-wmi.c
@@ -35,10 +35,6 @@ MODULE_LICENSE("GPL");
MODULE_ALIAS("wmi:95F24279-4D7B-4334-9387-ACCDC67EF61C");
MODULE_ALIAS("wmi:5FB7F034-2C63-45e9-BE91-3D44E2C707E4");

-static int enable_tablet_mode_sw = -1;
-module_param(enable_tablet_mode_sw, int, 0444);
-MODULE_PARM_DESC(enable_tablet_mode_sw, "Enable SW_TABLET_MODE reporting (-1=auto, 0=no, 1=yes)");
-
#define HPWMI_EVENT_GUID "95F24279-4D7B-4334-9387-ACCDC67EF61C"
#define HPWMI_BIOS_GUID "5FB7F034-2C63-45e9-BE91-3D44E2C707E4"
#define HP_OMEN_EC_THERMAL_PROFILE_OFFSET 0x95
@@ -107,6 +103,7 @@ enum hp_wmi_commandtype {
HPWMI_FEATURE2_QUERY = 0x0d,
HPWMI_WIRELESS2_QUERY = 0x1b,
HPWMI_POSTCODEERROR_QUERY = 0x2a,
+ HPWMI_SYSTEM_DEVICE_MODE = 0x40,
HPWMI_THERMAL_PROFILE_QUERY = 0x4c,
};

@@ -217,6 +214,19 @@ struct rfkill2_device {
static int rfkill2_count;
static struct rfkill2_device rfkill2[HPWMI_MAX_RFKILL2_DEVICES];

+/*
+ * Chassis Types values were obtained from SMBIOS reference
+ * specification version 3.00. A complete list of system enclosures
+ * and chassis types is available on Table 17.
+ */
+static const char * const tablet_chassis_types[] = {
+ "30", /* Tablet*/
+ "31", /* Convertible */
+ "32" /* Detachable */
+};
+
+#define DEVICE_MODE_TABLET 0x06
+
/* map output size to the corresponding WMI method id */
static inline int encode_outsize_for_pvsz(int outsize)
{
@@ -345,14 +355,39 @@ static int hp_wmi_read_int(int query)
return val;
}

-static int hp_wmi_hw_state(int mask)
+static int hp_wmi_get_dock_state(void)
{
int state = hp_wmi_read_int(HPWMI_HARDWARE_QUERY);

if (state < 0)
return state;

- return !!(state & mask);
+ return !!(state & HPWMI_DOCK_MASK);
+}
+
+static int hp_wmi_get_tablet_mode(void)
+{
+ char system_device_mode[4] = { 0 };
+ const char *chassis_type;
+ bool tablet_found;
+ int ret;
+
+ chassis_type = dmi_get_system_info(DMI_CHASSIS_TYPE);
+ if (!chassis_type)
+ return -ENODEV;
+
+ tablet_found = match_string(tablet_chassis_types,
+ ARRAY_SIZE(tablet_chassis_types),
+ chassis_type) >= 0;
+ if (!tablet_found)
+ return -ENODEV;
+
+ ret = hp_wmi_perform_query(HPWMI_SYSTEM_DEVICE_MODE, HPWMI_READ,
+ system_device_mode, 0, sizeof(system_device_mode));
+ if (ret < 0)
+ return ret;
+
+ return system_device_mode[0] == DEVICE_MODE_TABLET;
}

static int omen_thermal_profile_set(int mode)
@@ -568,7 +603,7 @@ static ssize_t als_show(struct device *dev, struct device_attribute *attr,
static ssize_t dock_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
- int value = hp_wmi_hw_state(HPWMI_DOCK_MASK);
+ int value = hp_wmi_get_dock_state();
if (value < 0)
return value;
return sprintf(buf, "%d\n", value);
@@ -577,7 +612,7 @@ static ssize_t dock_show(struct device *dev, struct device_attribute *attr,
static ssize_t tablet_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
- int value = hp_wmi_hw_state(HPWMI_TABLET_MASK);
+ int value = hp_wmi_get_tablet_mode();
if (value < 0)
return value;
return sprintf(buf, "%d\n", value);
@@ -699,10 +734,10 @@ static void hp_wmi_notify(u32 value, void *context)
case HPWMI_DOCK_EVENT:
if (test_bit(SW_DOCK, hp_wmi_input_dev->swbit))
input_report_switch(hp_wmi_input_dev, SW_DOCK,
- hp_wmi_hw_state(HPWMI_DOCK_MASK));
+ hp_wmi_get_dock_state());
if (test_bit(SW_TABLET_MODE, hp_wmi_input_dev->swbit))
input_report_switch(hp_wmi_input_dev, SW_TABLET_MODE,
- hp_wmi_hw_state(HPWMI_TABLET_MASK));
+ hp_wmi_get_tablet_mode());
input_sync(hp_wmi_input_dev);
break;
case HPWMI_PARK_HDD:
@@ -780,19 +815,17 @@ static int __init hp_wmi_input_setup(void)
__set_bit(EV_SW, hp_wmi_input_dev->evbit);

/* Dock */
- val = hp_wmi_hw_state(HPWMI_DOCK_MASK);
+ val = hp_wmi_get_dock_state();
if (!(val < 0)) {
__set_bit(SW_DOCK, hp_wmi_input_dev->swbit);
input_report_switch(hp_wmi_input_dev, SW_DOCK, val);
}

/* Tablet mode */
- if (enable_tablet_mode_sw > 0) {
- val = hp_wmi_hw_state(HPWMI_TABLET_MASK);
- if (val >= 0) {
- __set_bit(SW_TABLET_MODE, hp_wmi_input_dev->swbit);
- input_report_switch(hp_wmi_input_dev, SW_TABLET_MODE, val);
- }
+ val = hp_wmi_get_tablet_mode();
+ if (!(val < 0)) {
+ __set_bit(SW_TABLET_MODE, hp_wmi_input_dev->swbit);
+ input_report_switch(hp_wmi_input_dev, SW_TABLET_MODE, val);
}

err = sparse_keymap_setup(hp_wmi_input_dev, hp_wmi_keymap, NULL);
@@ -1227,10 +1260,10 @@ static int hp_wmi_resume_handler(struct device *device)
if (hp_wmi_input_dev) {
if (test_bit(SW_DOCK, hp_wmi_input_dev->swbit))
input_report_switch(hp_wmi_input_dev, SW_DOCK,
- hp_wmi_hw_state(HPWMI_DOCK_MASK));
+ hp_wmi_get_dock_state());
if (test_bit(SW_TABLET_MODE, hp_wmi_input_dev->swbit))
input_report_switch(hp_wmi_input_dev, SW_TABLET_MODE,
- hp_wmi_hw_state(HPWMI_TABLET_MASK));
+ hp_wmi_get_tablet_mode());
input_sync(hp_wmi_input_dev);
}

--
2.35.1