Re: [PATCH v3] platform/x86: inspur-wmi: Add platform profile support

From: Armin Wolf
Date: Wed Oct 18 2023 - 08:24:02 EST


Am 18.10.23 um 10:00 schrieb Ai Chao:

Add support for Inspur platforms to used the platform profile feature.

This will allow users to determine and control the platform modes
between low-power, balanced and performance modes.

change for v3
- Remove input device
- Using the platform profile interface

change for v2
- Remove Event GUID, remove inspur_wmi_notify and inspur_wmi_notify.
- Add more explanation.

Please move the changelog out of the commit message, see
https://lore.kernel.org/lkml/20231007081230.3555681-1-andriy.shevchenko@xxxxxxxxxxxxxxx
for an example.

Signed-off-by: Ai Chao <aichao@xxxxxxxxxx>
---
drivers/platform/x86/Kconfig | 10 ++
drivers/platform/x86/Makefile | 3 +
drivers/platform/x86/inspur-wmi.c | 215 ++++++++++++++++++++++++++++++
3 files changed, 228 insertions(+)
create mode 100644 drivers/platform/x86/inspur-wmi.c

diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index 2a1070543391..d7bd27c53751 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -988,6 +988,16 @@ config TOUCHSCREEN_DMI
the OS-image for the device. This option supplies the missing info.
Enable this for x86 tablets with Silead or Chipone touchscreens.

+config INSPUR_WMI
+ tristate "Inspur WMI platform profile driver"
+ depends on ACPI_WMI

Please select the platform profile subsystem with "select ACPI_PLATFORM_PROFILE".

+ help
+ This will allow users to determine and control the platform modes
+ between low-power, balanced and performance modes.
+
+ To compile this driver as a module, choose M here: the module
+ will be called inspur-wmi.
+
source "drivers/platform/x86/x86-android-tablets/Kconfig"

config FW_ATTR_CLASS
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index b457de5abf7d..9285c252757e 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -98,6 +98,9 @@ obj-$(CONFIG_TOSHIBA_WMI) += toshiba-wmi.o
# before toshiba_acpi initializes
obj-$(CONFIG_ACPI_TOSHIBA) += toshiba_acpi.o

+# Inspur
+obj-$(CONFIG_INSPUR_WMI) += inspur-wmi.o
+
# Laptop drivers
obj-$(CONFIG_ACPI_CMPC) += classmate-laptop.o
obj-$(CONFIG_COMPAL_LAPTOP) += compal-laptop.o
diff --git a/drivers/platform/x86/inspur-wmi.c b/drivers/platform/x86/inspur-wmi.c
new file mode 100644
index 000000000000..d0c5ae2e3fcb
--- /dev/null
+++ b/drivers/platform/x86/inspur-wmi.c
@@ -0,0 +1,215 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Inspur WMI power mode
+ *
+ * Copyright (C) 2018 Ai Chao <aichao@xxxxxxxxxx>
+ */
+
+#include <linux/acpi.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/platform_profile.h>
+#include <linux/wmi.h>
+
+#define WMI_INSPUR_POWERMODE_BIOS_GUID "596C31E3-332D-43C9-AEE9-585493284F5D"
+
+enum inspur_wmi_method_ids {
+ INSPUR_WMI_GET_POWERMODE = 0x02,
+ INSPUR_WMI_SET_POWERMODE = 0x03,
+};
+
+/**
+ * Power Mode:
+ * 0x0: Balance Mode
+ * 0x1: Performance Mode
+ * 0x2: Power Saver Mode
+ */
+enum inspur_tmp_profile {
+ INSPUR_TMP_PROFILE_BALANCE = 0,
+ INSPUR_TMP_PROFILE_PERFORMANCE = 1,
+ INSPUR_TMP_PROFILE_POWERSAVE = 2,
+};
+
+struct inspur_wmi_priv {
+ struct wmi_device *wdev;
+ struct platform_profile_handler handler;
+};
+
+static int inspur_wmi_perform_query(struct wmi_device *wdev,
+ enum inspur_wmi_method_ids query_id,
+ void *buffer, size_t insize,
+ size_t outsize)
+{
+ struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+ struct acpi_buffer input = { insize, buffer};
+ union acpi_object *obj;
+ acpi_status status;
+ int ret = 0;
+
+ status = wmidev_evaluate_method(wdev, 0, query_id, &input, &output);
+ if (ACPI_FAILURE(status)) {
+ dev_err(&wdev->dev, "EC Powermode control failed: %s\n",
+ acpi_format_exception(status));
+ return -EIO;
+ }
+
+ obj = output.pointer;
+ if (!obj)
+ return -EINVAL;
+
+ if (obj->type != ACPI_TYPE_BUFFER ||
+ obj->buffer.length != outsize) {
+ ret = -EINVAL;
+ goto out_free;
+ }
+
+ memcpy(buffer, obj->buffer.pointer, obj->buffer.length);
+
+out_free:
+ kfree(obj);
+ return ret;
+}
+
+/**
+ * Set Power Mode to EC RAM. If Power Mode value greater than 0x3,
+ * return error
+ * Method ID: 0x3
+ * Arg: 4 Bytes
+ * Byte [0]: Power Mode:
+ * 0x0: Balance Mode
+ * 0x1: Performance Mode
+ * 0x2: Power Saver Mode
+ * Return Value: 4 Bytes
+ * Byte [0]: Return Code
+ * 0x0: No Error
+ * 0x1: Error
+ */
+static int inspur_platform_profile_set(struct platform_profile_handler *pprof,
+ enum platform_profile_option profile)
+{
+ struct inspur_wmi_priv *priv = container_of(pprof, struct inspur_wmi_priv,
+ handler);
+ u8 ret_code[4] = {0, 0, 0, 0};
+ int ret;
+
+ switch (profile) {
+ case PLATFORM_PROFILE_BALANCED:
+ ret_code[0] = INSPUR_TMP_PROFILE_BALANCE;
+ break;
+ case PLATFORM_PROFILE_PERFORMANCE:
+ ret_code[0] = INSPUR_TMP_PROFILE_PERFORMANCE;
+ break;
+ case PLATFORM_PROFILE_LOW_POWER:
+ ret_code[0] = INSPUR_TMP_PROFILE_POWERSAVE;
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ ret = inspur_wmi_perform_query(priv->wdev, INSPUR_WMI_SET_POWERMODE,
+ ret_code, sizeof(ret_code),
+ sizeof(ret_code));
+
+ if (ret < 0)
+ return ret;
+ else if (ret_code[0])
+ return -EBADRQC;

That "else" is pointless due to the early return. Please move the ret_code[0] check
out of the else clause, like this:

if (ret < 0)
return ret;

if (ret_code[0])
return -EBADRQC;

+
+ return 0;
+}
+
+/**
+ * Get Power Mode from EC RAM, If Power Mode value greater than 0x3,
+ * return error
+ * Method ID: 0x2
+ * Return Value: 4 Bytes
+ * Byte [0]: Return Code
+ * 0x0: No Error
+ * 0x1: Error
+ * Byte [1]: Power Mode
+ * 0x0: Balance Mode
+ * 0x1: Performance Mode
+ * 0x2: Power Saver Mode
+ */
+static int inspur_platform_profile_get(struct platform_profile_handler *pprof,
+ enum platform_profile_option *profile)
+{
+ struct inspur_wmi_priv *priv = container_of(pprof, struct inspur_wmi_priv,
+ handler);
+ u8 ret_code[4] = {0, 0, 0, 0};
+ int ret;
+
+ ret = inspur_wmi_perform_query(priv->wdev, INSPUR_WMI_GET_POWERMODE,
+ &ret_code, sizeof(ret_code),
+ sizeof(ret_code));
+ if (ret < 0)
+ return ret;
+ else if (ret_code[0])
+ return -EBADRQC;

Same as above.

+
+ switch (ret_code[1]) {
+ case INSPUR_TMP_PROFILE_BALANCE:
+ *profile = PLATFORM_PROFILE_BALANCED;
+ break;
+ case INSPUR_TMP_PROFILE_PERFORMANCE:
+ *profile = PLATFORM_PROFILE_PERFORMANCE;
+ break;
+ case INSPUR_TMP_PROFILE_POWERSAVE:
+ *profile = PLATFORM_PROFILE_LOW_POWER;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int inspur_wmi_probe(struct wmi_device *wdev, const void *context)
+{
+ struct inspur_wmi_priv *priv;
+
+ priv = devm_kzalloc(&wdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->wdev = wdev;
+ dev_set_drvdata(&wdev->dev, priv);
+
+ priv->handler.profile_get = inspur_platform_profile_get;
+ priv->handler.profile_set = inspur_platform_profile_set;
+
+ set_bit(PLATFORM_PROFILE_LOW_POWER, priv->handler.choices);
+ set_bit(PLATFORM_PROFILE_BALANCED, priv->handler.choices);
+ set_bit(PLATFORM_PROFILE_PERFORMANCE, priv->handler.choices);
+
+ platform_profile_register(&priv->handler);
+ return 0;

I said that the surface platform profile driver was a good example _except_ for this
minor issue. Please return the result of platform_profile_register(), see
https://lore.kernel.org/lkml/20231014235449.288702-1-W_Armin@xxxxxx for an explanation.

Other than that and the remaining issues above, the driver looks good to me.

Armin Wolf

+}
+
+static void inspur_wmi_remove(struct wmi_device *wdev)
+{
+ platform_profile_remove();
+}
+
+static const struct wmi_device_id inspur_wmi_id_table[] = {
+ { .guid_string = WMI_INSPUR_POWERMODE_BIOS_GUID },
+ { }
+};
+
+MODULE_DEVICE_TABLE(wmi, inspur_wmi_id_table);
+
+static struct wmi_driver inspur_wmi_driver = {
+ .driver = {
+ .name = "inspur-wmi",
+ .probe_type = PROBE_PREFER_ASYNCHRONOUS,
+ },
+ .id_table = inspur_wmi_id_table,
+ .probe = inspur_wmi_probe,
+ .remove = inspur_wmi_remove,
+};
+
+module_wmi_driver(inspur_wmi_driver);
+
+MODULE_AUTHOR("Ai Chao <aichao@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Inspur WMI hotkeys");
+MODULE_LICENSE("GPL");