[PATCH v2 3/6] platform/x86: huawei-wmi: Implement huawei wmi management
From: Ayman Bagabas
Date: Wed Sep 18 2019 - 20:56:11 EST
Huawei Matebook laptops come with a WMI management interface that can
control various aspects of the device. This interface is also found on
the old Matebook X released in 2017.
Use that to control the mic mute LED.
Signed-off-by: Ayman Bagabas <ayman.bagabas@xxxxxxxxx>
---
drivers/platform/x86/huawei-wmi.c | 217 +++++++++++++++++++++++++-----
1 file changed, 180 insertions(+), 37 deletions(-)
diff --git a/drivers/platform/x86/huawei-wmi.c b/drivers/platform/x86/huawei-wmi.c
index 97ff3d868765..904ef38944b6 100644
--- a/drivers/platform/x86/huawei-wmi.c
+++ b/drivers/platform/x86/huawei-wmi.c
@@ -11,18 +11,35 @@
#include <linux/input/sparse-keymap.h>
#include <linux/leds.h>
#include <linux/module.h>
+#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <linux/wmi.h>
/*
* Huawei WMI GUIDs
*/
+#define HWMI_METHOD_GUID "ABBC0F5B-8EA1-11D1-A000-C90629100000"
#define HWMI_EVENT_GUID "ABBC0F5C-8EA1-11D1-A000-C90629100000"
/* Legacy GUIDs */
#define WMI0_EXPENSIVE_GUID "39142400-C6A3-40fa-BADB-8A2652834100"
#define WMI0_EVENT_GUID "59142400-C6A3-40fa-BADB-8A2652834100"
+/* HWMI commands */
+
+enum {
+ BATTERY_THRESH_GET = 0x00001103, /* \GBTT */
+ BATTERY_THRESH_SET = 0x00001003, /* \SBTT */
+ FN_LOCK_GET = 0x00000604, /* \GFRS */
+ FN_LOCK_SET = 0x00000704, /* \SFRS */
+ MICMUTE_LED_SET = 0x00000b04, /* \SMLS */
+};
+
+union hwmi_arg {
+ u64 cmd;
+ u8 args[8];
+};
+
struct quirk_entry {
bool battery_reset;
bool ec_micmute;
@@ -41,8 +58,8 @@ struct huawei_wmi {
struct input_dev *idev[2];
struct led_classdev cdev;
struct platform_device *pdev;
- acpi_handle handle;
- char *acpi_method;
+
+ struct mutex wmi_lock;
};
struct huawei_wmi *huawei_wmi;
@@ -116,52 +133,168 @@ static const struct dmi_system_id huawei_quirks[] = {
{ }
};
+/* Utils */
+
+static int huawei_wmi_call(struct acpi_buffer *in, struct acpi_buffer *out)
+{
+ acpi_status status;
+
+ mutex_lock(&huawei_wmi->wmi_lock);
+ status = wmi_evaluate_method(HWMI_METHOD_GUID, 0, 1, in, out);
+ mutex_unlock(&huawei_wmi->wmi_lock);
+ if (ACPI_FAILURE(status)) {
+ dev_err(&huawei_wmi->pdev->dev, "Failed to evaluate wmi method\n");
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+/* HWMI takes a 64 bit input and returns either a package with 2 buffers, one of
+ * 4 bytes and the other of 256 bytes, or one buffer of size 0x104 (260) bytes.
+ * The first 4 bytes are ignored, we ignore the first 4 bytes buffer if we got a
+ * package, or skip the first 4 if a buffer of 0x104 is used. The first byte of
+ * the remaining 0x100 sized buffer has the return status of every call. In case
+ * the return status is non-zero, we return -ENODEV but still copy the returned
+ * buffer to the given buffer parameter (buf).
+ */
+static int huawei_wmi_cmd(u64 arg, u8 *buf, size_t buflen)
+{
+ struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
+ struct acpi_buffer in;
+ union acpi_object *obj;
+ size_t len;
+ int err, i;
+
+ in.length = sizeof(arg);
+ in.pointer = &arg;
+
+ /* Some models require calling HWMI twice to execute a command. We evaluate
+ * HWMI and if we get a non-zero return status we evaluate it again.
+ */
+ for (i = 0; i < 2; i++) {
+ err = huawei_wmi_call(&in, &out);
+ if (err)
+ goto fail_cmd;
+
+ obj = out.pointer;
+ if (!obj) {
+ err = -EIO;
+ goto fail_cmd;
+ }
+
+ switch (obj->type) {
+ /* Models that implement both "legacy" and HWMI tend to return a 0x104
+ * sized buffer instead of a package of 0x4 and 0x100 buffers.
+ */
+ case ACPI_TYPE_BUFFER:
+ if (obj->buffer.length == 0x104) {
+ // Skip the first 4 bytes.
+ obj->buffer.pointer += 4;
+ len = 0x100;
+ } else {
+ dev_err(&huawei_wmi->pdev->dev, "Bad buffer length, got %d\n", obj->buffer.length);
+ err = -EIO;
+ goto fail_cmd;
+ }
+
+ break;
+ /* HWMI returns a package with 2 buffer elements, one of 4 bytes and the
+ * other is 256 bytes.
+ */
+ case ACPI_TYPE_PACKAGE:
+ if (obj->package.count != 2) {
+ dev_err(&huawei_wmi->pdev->dev, "Bad package count, got %d\n", obj->package.count);
+ err = -EIO;
+ goto fail_cmd;
+ }
+
+ obj = &obj->package.elements[1];
+ if (obj->type != ACPI_TYPE_BUFFER) {
+ dev_err(&huawei_wmi->pdev->dev, "Bad package element type, got %d\n", obj->type);
+ err = -EIO;
+ goto fail_cmd;
+ }
+ len = obj->buffer.length;
+
+ break;
+ /* Shouldn't get here! */
+ default:
+ dev_err(&huawei_wmi->pdev->dev, "Unexpected obj type, got: %d\n", obj->type);
+ err = -EIO;
+ goto fail_cmd;
+ }
+
+ if (!*obj->buffer.pointer)
+ break;
+ }
+
+ err = (*obj->buffer.pointer) ? -ENODEV : 0;
+
+ if (buf) {
+ len = min(buflen, len);
+ memcpy(buf, obj->buffer.pointer, len);
+ }
+
+fail_cmd:
+ kfree(out.pointer);
+ return err;
+}
+
+/* LEDs */
+
static int huawei_wmi_micmute_led_set(struct led_classdev *led_cdev,
enum led_brightness brightness)
{
- struct huawei_wmi *huawei = dev_get_drvdata(led_cdev->dev->parent);
- acpi_status status;
- union acpi_object args[3];
- struct acpi_object_list arg_list = {
- .pointer = args,
- .count = ARRAY_SIZE(args),
- };
-
- args[0].type = args[1].type = args[2].type = ACPI_TYPE_INTEGER;
- args[1].integer.value = 0x04;
-
- if (strcmp(huawei->acpi_method, "SPIN") == 0) {
- args[0].integer.value = 0;
- args[2].integer.value = brightness ? 1 : 0;
- } else if (strcmp(huawei->acpi_method, "WPIN") == 0) {
- args[0].integer.value = 1;
- args[2].integer.value = brightness ? 0 : 1;
+ /* This is a workaround until the "legacy" interface is implemented. */
+ if (quirks && quirks->ec_micmute) {
+ char *acpi_method;
+ acpi_handle handle;
+ acpi_status status;
+ union acpi_object args[3];
+ struct acpi_object_list arg_list = {
+ .pointer = args,
+ .count = ARRAY_SIZE(args),
+ };
+
+ handle = ec_get_handle();
+ if (!handle)
+ return -ENODEV;
+
+ args[0].type = args[1].type = args[2].type = ACPI_TYPE_INTEGER;
+ args[1].integer.value = 0x04;
+
+ if (acpi_has_method(handle, "SPIN")) {
+ acpi_method = "SPIN";
+ args[0].integer.value = 0;
+ args[2].integer.value = brightness ? 1 : 0;
+ } else if (acpi_has_method(handle, "WPIN")) {
+ acpi_method = "WPIN";
+ args[0].integer.value = 1;
+ args[2].integer.value = brightness ? 0 : 1;
+ } else {
+ return -ENODEV;
+ }
+
+ status = acpi_evaluate_object(handle, acpi_method, &arg_list, NULL);
+ if (ACPI_FAILURE(status))
+ return -ENODEV;
+
+ return 0;
} else {
- return -EINVAL;
- }
+ union hwmi_arg arg;
- status = acpi_evaluate_object(huawei->handle, huawei->acpi_method, &arg_list, NULL);
- if (ACPI_FAILURE(status))
- return -ENXIO;
+ arg.cmd = MICMUTE_LED_SET;
+ arg.args[2] = brightness;
- return 0;
+ return huawei_wmi_cmd(arg.cmd, NULL, NULL);
+ }
}
static void huawei_wmi_leds_setup(struct device *dev)
{
struct huawei_wmi *huawei = dev_get_drvdata(dev);
- huawei->handle = ec_get_handle();
- if (!huawei->handle)
- return;
-
- if (acpi_has_method(huawei->handle, "SPIN"))
- huawei->acpi_method = "SPIN";
- else if (acpi_has_method(huawei->handle, "WPIN"))
- huawei->acpi_method = "WPIN";
- else
- return;
-
huawei->cdev.name = "platform::micmute";
huawei->cdev.max_brightness = 1;
huawei->cdev.brightness_set_blocking = &huawei_wmi_micmute_led_set;
@@ -264,6 +397,7 @@ static void huawei_wmi_input_exit(struct device *dev, const char *guid)
static const struct wmi_device_id huawei_wmi_events_id_table[] = {
{ .guid_string = WMI0_EVENT_GUID },
+ { .guid_string = HWMI_EVENT_GUID },
{ }
};
@@ -290,7 +424,12 @@ static int huawei_wmi_probe(struct platform_device *pdev)
guid++;
}
- huawei_wmi_leds_setup(&pdev->dev);
+ if (wmi_has_guid(HWMI_METHOD_GUID)) {
+ mutex_init(&huawei_wmi->wmi_lock);
+
+ huawei_wmi_leds_setup(&pdev->dev);
+ }
+
return 0;
}
@@ -305,6 +444,9 @@ static int huawei_wmi_remove(struct platform_device *pdev)
guid++;
}
+ if (wmi_has_guid(HWMI_METHOD_GUID)) {
+ }
+
return 0;
}
@@ -358,6 +500,7 @@ static __exit void huawei_wmi_exit(void)
module_init(huawei_wmi_init);
module_exit(huawei_wmi_exit);
+MODULE_ALIAS("wmi:"HWMI_METHOD_GUID);
MODULE_DEVICE_TABLE(wmi, huawei_wmi_events_id_table);
MODULE_AUTHOR("Ayman Bagabas <ayman.bagabas@xxxxxxxxx>");
MODULE_DESCRIPTION("Huawei WMI laptop extras driver");
--
2.21.0