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Diffstat (limited to 'drivers/hwmon/hp-wmi-sensors.c')
-rw-r--r--drivers/hwmon/hp-wmi-sensors.c149
1 files changed, 118 insertions, 31 deletions
diff --git a/drivers/hwmon/hp-wmi-sensors.c b/drivers/hwmon/hp-wmi-sensors.c
index 17ae62f88bbf..03c684ba83bd 100644
--- a/drivers/hwmon/hp-wmi-sensors.c
+++ b/drivers/hwmon/hp-wmi-sensors.c
@@ -17,6 +17,8 @@
* Available: https://github.com/linuxhw/ACPI
* [4] P. Rohár, "bmfdec - Decompile binary MOF file (BMF) from WMI buffer",
* 2017. [Online]. Available: https://github.com/pali/bmfdec
+ * [5] Microsoft Corporation, "Driver-Defined WMI Data Items", 2017. [Online].
+ * Available: https://learn.microsoft.com/en-us/windows-hardware/drivers/kernel/driver-defined-wmi-data-items
*/
#include <linux/acpi.h>
@@ -24,6 +26,7 @@
#include <linux/hwmon.h>
#include <linux/jiffies.h>
#include <linux/mutex.h>
+#include <linux/nls.h>
#include <linux/units.h>
#include <linux/wmi.h>
@@ -395,6 +398,50 @@ struct hp_wmi_sensors {
struct mutex lock; /* Lock polling WMI and driver state changes. */
};
+static bool is_raw_wmi_string(const u8 *pointer, u32 length)
+{
+ const u16 *ptr;
+ u16 len;
+
+ /* WMI strings are length-prefixed UTF-16 [5]. */
+ if (length <= sizeof(*ptr))
+ return false;
+
+ length -= sizeof(*ptr);
+ ptr = (const u16 *)pointer;
+ len = *ptr;
+
+ return len <= length && !(len & 1);
+}
+
+static char *convert_raw_wmi_string(const u8 *buf)
+{
+ const wchar_t *src;
+ unsigned int cps;
+ unsigned int len;
+ char *dst;
+ int i;
+
+ src = (const wchar_t *)buf;
+
+ /* Count UTF-16 code points. Exclude trailing null padding. */
+ cps = *src / sizeof(*src);
+ while (cps && !src[cps])
+ cps--;
+
+ /* Each code point becomes up to 3 UTF-8 characters. */
+ len = min(cps * 3, HP_WMI_MAX_STR_SIZE - 1);
+
+ dst = kmalloc((len + 1) * sizeof(*dst), GFP_KERNEL);
+ if (!dst)
+ return NULL;
+
+ i = utf16s_to_utf8s(++src, cps, UTF16_LITTLE_ENDIAN, dst, len);
+ dst[i] = '\0';
+
+ return dst;
+}
+
/* hp_wmi_strdup - devm_kstrdup, but length-limited */
static char *hp_wmi_strdup(struct device *dev, const char *src)
{
@@ -412,6 +459,23 @@ static char *hp_wmi_strdup(struct device *dev, const char *src)
return dst;
}
+/* hp_wmi_wstrdup - hp_wmi_strdup, but for a raw WMI string */
+static char *hp_wmi_wstrdup(struct device *dev, const u8 *buf)
+{
+ char *src;
+ char *dst;
+
+ src = convert_raw_wmi_string(buf);
+ if (!src)
+ return NULL;
+
+ dst = hp_wmi_strdup(dev, strim(src)); /* Note: Copy is trimmed. */
+
+ kfree(src);
+
+ return dst;
+}
+
/*
* hp_wmi_get_wobj - poll WMI for a WMI object instance
* @guid: WMI object GUID
@@ -462,8 +526,14 @@ static int check_wobj(const union acpi_object *wobj,
for (prop = 0; prop <= last_prop; prop++) {
type = elements[prop].type;
valid_type = property_map[prop];
- if (type != valid_type)
+ if (type != valid_type) {
+ if (type == ACPI_TYPE_BUFFER &&
+ valid_type == ACPI_TYPE_STRING &&
+ is_raw_wmi_string(elements[prop].buffer.pointer,
+ elements[prop].buffer.length))
+ continue;
return -EINVAL;
+ }
}
return 0;
@@ -480,7 +550,9 @@ static int extract_acpi_value(struct device *dev,
break;
case ACPI_TYPE_STRING:
- *out_string = hp_wmi_strdup(dev, strim(element->string.pointer));
+ *out_string = element->type == ACPI_TYPE_BUFFER ?
+ hp_wmi_wstrdup(dev, element->buffer.pointer) :
+ hp_wmi_strdup(dev, strim(element->string.pointer));
if (!*out_string)
return -ENOMEM;
break;
@@ -861,7 +933,9 @@ update_numeric_sensor_from_wobj(struct device *dev,
{
const union acpi_object *elements;
const union acpi_object *element;
- const char *string;
+ const char *new_string;
+ char *trimmed;
+ char *string;
bool is_new;
int offset;
u8 size;
@@ -885,11 +959,21 @@ update_numeric_sensor_from_wobj(struct device *dev,
offset = is_new ? size - 1 : -2;
element = &elements[HP_WMI_PROPERTY_CURRENT_STATE + offset];
- string = strim(element->string.pointer);
-
- if (strcmp(string, nsensor->current_state)) {
- devm_kfree(dev, nsensor->current_state);
- nsensor->current_state = hp_wmi_strdup(dev, string);
+ string = element->type == ACPI_TYPE_BUFFER ?
+ convert_raw_wmi_string(element->buffer.pointer) :
+ element->string.pointer;
+
+ if (string) {
+ trimmed = strim(string);
+ if (strcmp(trimmed, nsensor->current_state)) {
+ new_string = hp_wmi_strdup(dev, trimmed);
+ if (new_string) {
+ devm_kfree(dev, nsensor->current_state);
+ nsensor->current_state = new_string;
+ }
+ }
+ if (element->type == ACPI_TYPE_BUFFER)
+ kfree(string);
}
/* Old variant: -2 (not -1) because it lacks the Size property. */
@@ -996,11 +1080,15 @@ static int check_event_wobj(const union acpi_object *wobj)
HP_WMI_EVENT_PROPERTY_STATUS);
}
-static int populate_event_from_wobj(struct hp_wmi_event *event,
+static int populate_event_from_wobj(struct device *dev,
+ struct hp_wmi_event *event,
union acpi_object *wobj)
{
int prop = HP_WMI_EVENT_PROPERTY_NAME;
union acpi_object *element;
+ acpi_object_type type;
+ char *string;
+ u32 value;
int err;
err = check_event_wobj(wobj);
@@ -1009,20 +1097,24 @@ static int populate_event_from_wobj(struct hp_wmi_event *event,
element = wobj->package.elements;
- /* Extracted strings are NOT device-managed copies. */
-
for (; prop <= HP_WMI_EVENT_PROPERTY_CATEGORY; prop++, element++) {
+ type = hp_wmi_event_property_map[prop];
+
+ err = extract_acpi_value(dev, element, type, &value, &string);
+ if (err)
+ return err;
+
switch (prop) {
case HP_WMI_EVENT_PROPERTY_NAME:
- event->name = strim(element->string.pointer);
+ event->name = string;
break;
case HP_WMI_EVENT_PROPERTY_DESCRIPTION:
- event->description = strim(element->string.pointer);
+ event->description = string;
break;
case HP_WMI_EVENT_PROPERTY_CATEGORY:
- event->category = element->integer.value;
+ event->category = value;
break;
default:
@@ -1105,7 +1197,7 @@ static int hp_wmi_update_info(struct hp_wmi_sensors *state,
if (time_after(jiffies, info->last_updated + HZ)) {
mutex_lock(&state->lock);
- wobj = hp_wmi_get_wobj(HP_WMI_NUMERIC_SENSOR_GUID, instance);
+ wobj = wmidev_block_query(state->wdev, instance);
if (!wobj) {
ret = -EIO;
goto out_unlock;
@@ -1505,15 +1597,13 @@ static void hp_wmi_devm_notify_remove(void *ignored)
}
/* hp_wmi_notify - WMI event notification handler */
-static void hp_wmi_notify(u32 value, void *context)
+static void hp_wmi_notify(union acpi_object *wobj, void *context)
{
struct hp_wmi_info *temp_info[HP_WMI_MAX_INSTANCES] = {};
- struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
struct hp_wmi_sensors *state = context;
struct device *dev = &state->wdev->dev;
+ struct hp_wmi_event event = {};
struct hp_wmi_info *fan_info;
- struct hp_wmi_event event;
- union acpi_object *wobj;
acpi_status err;
int event_type;
u8 count;
@@ -1538,18 +1628,15 @@ static void hp_wmi_notify(u32 value, void *context)
* HPBIOS_BIOSEvent instance.
*/
- mutex_lock(&state->lock);
-
- err = wmi_get_event_data(value, &out);
- if (ACPI_FAILURE(err))
- goto out_unlock;
+ if (!wobj)
+ return;
- wobj = out.pointer;
+ mutex_lock(&state->lock);
- err = populate_event_from_wobj(&event, wobj);
+ err = populate_event_from_wobj(dev, &event, wobj);
if (err) {
dev_warn(dev, "Bad event data (ACPI type %d)\n", wobj->type);
- goto out_free_wobj;
+ goto out_free;
}
event_type = classify_event(event.name, event.category);
@@ -1574,10 +1661,10 @@ static void hp_wmi_notify(u32 value, void *context)
break;
}
-out_free_wobj:
- kfree(wobj);
+out_free:
+ devm_kfree(dev, event.name);
+ devm_kfree(dev, event.description);
-out_unlock:
mutex_unlock(&state->lock);
}
@@ -1658,7 +1745,7 @@ static int init_numeric_sensors(struct hp_wmi_sensors *state,
return -ENOMEM;
for (i = 0, info = info_arr; i < icount; i++, info++) {
- wobj = hp_wmi_get_wobj(HP_WMI_NUMERIC_SENSOR_GUID, i);
+ wobj = wmidev_block_query(state->wdev, i);
if (!wobj)
return -EIO;
generated by cgit (git 2.34.1) at 2025-12-24 21:46:57 +0000