[PATCH v3 0/2] Update ASUS WMI supported boards

[PATCH v3 0/2] Update ASUS WMI supported boards

[Denis Pauk]

Add support by WMI interface privided by Asus for B550/X570 boards: 
* PRIME X570-PRO,
* ROG CROSSHAIR VIII HERO
* ROG CROSSHAIR VIII DARK HERO
* ROG CROSSHAIR VIII FORMULA
* ROG STRIX X570-E GAMING
* ROG STRIX B550-E GAMING

Add support by WMI interface privided by Asus for X370/X470/
B450/X399 boards:
* ROG CROSSHAIR VI HERO,
* PRIME X399-A,
* PRIME X470-PRO,
* ROG CROSSHAIR VI EXTREME,
* ROG CROSSHAIR VI HERO (WI-FI AC),
* ROG CROSSHAIR VII HERO,
* ROG CROSSHAIR VII HERO (WI-FI),
* ROG STRIX B450-E GAMING,
* ROG STRIX B450-F GAMING,
* ROG STRIX B450-I GAMING,
* ROG STRIX X399-E GAMING,
* ROG STRIX X470-F GAMING,
* ROG STRIX X470-I GAMING,
* ROG ZENITH EXTREME,
* ROG ZENITH EXTREME ALPHA.

Could you please review?

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=204807
Signed-off-by: Denis Pauk <pauk.denis@gmail.com>
Signed-off-by: Ed Brindley <kernel@maidavale.org>
Signed-off-by: Eugene Shalygin <eugene.shalygin@gmail.com>

---
Changes in v3:
 - Use MODULE_DEVICE_TABLE for match devices.
 - asus_wmi_ec_sensors: Use get_unaligned_be32 instead incorrectly used 
   get_unaligned_le32.
 - Add documentaion for drivers.

Changes in v2:
 - asus_wmi_ec_sensors: Rename asus_wmi_sensors to asus_wmi_ec_sensors for 
   B550/X570 boards.
 - asus_wmi_ec_sensors: Use utf8s_to_utf16s/utf16s_to_utf8s instead handmade 
   fuctions.
 - asus_wmi_ec_sensors: Use post increment.
 - asus_wmi_ec_sensors: Use get_unaligned* for convert values.
 - asus_wmi_ec_sensors: Use PTR_ERR_OR_ZERO.
 - asus_wmi_ec_sensors: Specify per-board sensors in a declarative way 
   (by Eugene Shalygin).
 - asus_wmi_sensors: Add support for X370/X470/B450/X399 boards.
 
---

Denis Pauk (2):
  hwmon: (asus_wmi_ec_sensors) Support B550 Asus WMI.
  hwmon: (asus_wmi_sensors) Support X370 Asus WMI.

 Documentation/hwmon/asus_wmi_ec_sensors.rst |  35 ++
 Documentation/hwmon/asus_wmi_sensors.rst    |  62 ++
 MAINTAINERS                                 |   8 +
 drivers/hwmon/Kconfig                       |  22 +
 drivers/hwmon/Makefile                      |   2 +
 drivers/hwmon/asus_wmi_ec_sensors.c         | 659 ++++++++++++++++++++
 drivers/hwmon/asus_wmi_sensors.c            | 635 +++++++++++++++++++
 7 files changed, 1423 insertions(+)
 create mode 100644 Documentation/hwmon/asus_wmi_ec_sensors.rst
 create mode 100644 Documentation/hwmon/asus_wmi_sensors.rst
 create mode 100644 drivers/hwmon/asus_wmi_ec_sensors.c
 create mode 100644 drivers/hwmon/asus_wmi_sensors.c


base-commit: 39b483aa38995329326988cbc4077422bebc175a
-- 
2.33.0

[PATCH v3 1/2] hwmon: (asus_wmi_ec_sensors) Support B550 Asus WMI.

[Denis Pauk]

Linux HWMON sensors driver for ASUS motherboards to read
sensors from the embedded controller.

Many ASUS motherboards do not publish all the available
sensors via the Super I/O chip but the missing ones are
available through the embedded controller (EC) registers.

This driver implements reading those sensor data via the
WMI method BREC, which is known to be present in all ASUS
motherboards based on the AMD 500 series chipsets (and
probably is available in other models too). The driver
needs to know exact register addresses for the sensors and
thus support for each motherboard has to be added explicitly.

The EC registers do not provide critical values for the
sensors and as such they are not published to the HWMON.

Supported motherboards:
* PRIME X570-PRO
* ROG CROSSHAIR VIII HERO
* ROG CROSSHAIR VIII DARK HERO
* ROG CROSSHAIR VIII FORMULA
* ROG STRIX X570-E GAMING
* ROG STRIX B550-E GAMING

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=204807
Signed-off-by: Denis Pauk <pauk.denis@gmail.com>
Co-developed-by: Eugene Shalygin <eugene.shalygin@gmail.com>
Signed-off-by: Eugene Shalygin <eugene.shalygin@gmail.com>
Tested-by: Tor Vic <torvic9@mailbox.org>

---
Changes in v3:
 - Use MODULE_DEVICE_TABLE for match devices.
 - Use get_unaligned_be32 instead incorrectly used get_unaligned_le32.
 - Add documentaion for driver.

Changes in v2:
 - Use utf8s_to_utf16s/utf16s_to_utf8s instead handmade fuctions.
 - Use post increment.
 - Use get_unaligned* for convert values.
 - Use PTR_ERR_OR_ZERO.
 - Specify per-board sensors in a declarative way (by Eugene Shalygin).
---
 Documentation/hwmon/asus_wmi_ec_sensors.rst |  35 ++
 MAINTAINERS                                 |   7 +
 drivers/hwmon/Kconfig                       |  11 +
 drivers/hwmon/Makefile                      |   1 +
 drivers/hwmon/asus_wmi_ec_sensors.c         | 659 ++++++++++++++++++++
 5 files changed, 713 insertions(+)
 create mode 100644 Documentation/hwmon/asus_wmi_ec_sensors.rst
 create mode 100644 drivers/hwmon/asus_wmi_ec_sensors.c

diff --git a/Documentation/hwmon/asus_wmi_ec_sensors.rst b/Documentation/hwmon/asus_wmi_ec_sensors.rst
new file mode 100644
index 000000000000..e4f603804a82
--- /dev/null
+++ b/Documentation/hwmon/asus_wmi_ec_sensors.rst
@@ -0,0 +1,35 @@
+Kernel driver asus-wmi-ec-sensors
+=================================
+
+Supported boards:
+ * PRIME X570-PRO,
+ * Pro WS X570-ACE,
+ * ROG CROSSHAIR VIII DARK HERO,
+ * ROG CROSSHAIR VIII FORMULA,
+ * ROG CROSSHAIR VIII HERO,
+ * ROG STRIX B550-E GAMING,
+ * ROG STRIX X570-E GAMING.
+
+Authors:
+        Eugene Shalygin <eugene.shalygin@gmail.com>
+
+Description:
+------------
+ASUS mainboards publish hardware monitoring information via Super I/O
+chip and the ACPI embedded controller (EC) registers. Some of the sensors
+are only available via the EC.
+
+ASUS WMI interface provides a method (BREC) to read data from EC registers,
+which is utilized by this driver to publish those sensor readings to the
+HWMON system. The driver is aware of and reads the following sensors:
+
+1. Chipset (PCH) temperature
+2. CPU package temperature
+3. Motherboard temperature
+4. Readings from the T_Sensor header
+5. VRM temperature
+6. CPU_Opt fan RPM
+7. Chipset fan RPM
+8. Readings from the "Water flow meter" header (RPM)
+9. Readings from the "Water In" and "Water Out" temperature headers
+10. CPU current
diff --git a/MAINTAINERS b/MAINTAINERS
index cc5eaf4e65dc..05448435991d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2937,6 +2937,13 @@ W:	http://acpi4asus.sf.net
 F:	drivers/platform/x86/asus*.c
 F:	drivers/platform/x86/eeepc*.c
 
+ASUS WMI HARDWARE MONITOR DRIVER
+M:	Eugene Shalygin <eugene.shalygin@gmail.com>
+M:	Denis Pauk <pauk.denis@gmail.com>
+L:	linux-hwmon@vger.kernel.org
+S:	Maintained
+F:	drivers/hwmon/asus_wmi_ec_sensors.c
+
 ASUS WIRELESS RADIO CONTROL DRIVER
 M:	João Paulo Rechi Vita <jprvita@gmail.com>
 L:	platform-driver-x86@vger.kernel.org
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 7fde4c6e1e7f..430a438432a0 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -2215,6 +2215,17 @@ config SENSORS_ATK0110
 	  This driver can also be built as a module. If so, the module
 	  will be called asus_atk0110.
 
+config SENSORS_ASUS_WMI_EC
+	tristate "ASUS WMI B550/X570"
+	help
+	  If you say yes here you get support for the ACPI embedded controller
+	  hardware monitoring interface found in B550/X570 ASUS motherboards.
+	  This driver will provide readings of fans, voltages and temperatures
+	  through the system firmware.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called asus_wmi_sensors_ec.
+
 endif # ACPI
 
 endif # HWMON
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index baee6a8d4dd1..aae2ff5c7335 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_HWMON_VID)		+= hwmon-vid.o
 # APCI drivers
 obj-$(CONFIG_SENSORS_ACPI_POWER) += acpi_power_meter.o
 obj-$(CONFIG_SENSORS_ATK0110)	+= asus_atk0110.o
+obj-$(CONFIG_SENSORS_ASUS_WMI_EC)	+= asus_wmi_ec_sensors.o
 
 # Native drivers
 # asb100, then w83781d go first, as they can override other drivers' addresses.
diff --git a/drivers/hwmon/asus_wmi_ec_sensors.c b/drivers/hwmon/asus_wmi_ec_sensors.c
new file mode 100644
index 000000000000..98b36e0ab515
--- /dev/null
+++ b/drivers/hwmon/asus_wmi_ec_sensors.c
@@ -0,0 +1,659 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * HWMON driver for ASUS B550/X570 motherboards that publish sensor
+ * values via the embedded controller registers.
+ *
+ * Copyright (C) 2021 Eugene Shalygin <eugene.shalygin@gmail.com>
+ * Copyright (C) 2018-2019 Ed Brindley <kernel@maidavale.org>
+ *
+ * EC provides:
+ * Chipset temperature,
+ * CPU temperature,
+ * Motherboard temperature,
+ * T_Sensor temperature,
+ * VRM  temperature,
+ * Water In temperature,
+ * Water Out temperature,
+ * CPU Optional Fan RPM,
+ * Chipset Fan RPM,
+ * Water Flow Fan RPM,
+ * CPU current.
+ *
+ */
+#include <asm/unaligned.h>
+#include <linux/acpi.h>
+#include <linux/dmi.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/init.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/nls.h>
+#include <linux/platform_device.h>
+#include <linux/units.h>
+#include <linux/wmi.h>
+
+#define ASUSWMI_MONITORING_GUID		"466747A0-70EC-11DE-8A39-0800200C9A66"
+#define ASUSWMI_METHODID_BLOCK_READ_EC		0x42524543 /* BREC */
+
+#define ASUS_WMI_BLOCK_READ_REGISTERS_MAX 0x10 /* from the ASUS DSDT source */
+/* from the ASUS_WMI_BLOCK_READ_REGISTERS_MAX value */
+#define ASUS_WMI_MAX_BUF_LEN 0x80
+#define MAX_SENSOR_LABEL_LENGTH 0x10
+
+static u32 hwmon_attributes[] = {
+	[hwmon_chip] = HWMON_C_REGISTER_TZ,
+	[hwmon_temp] = HWMON_T_INPUT | HWMON_T_LABEL,
+	[hwmon_in] = HWMON_I_INPUT | HWMON_I_LABEL,
+	[hwmon_curr] = HWMON_C_INPUT | HWMON_C_LABEL,
+	[hwmon_fan] = HWMON_F_INPUT | HWMON_F_LABEL,
+};
+
+struct asus_wmi_ec_sensor_address {
+	u8 index;
+	u8 bank;
+	u8 size;
+};
+
+#define MAKE_SENSOR_ADDRESS(size_i, bank_i, index_i) \
+	{ .size = size_i,\
+	   .bank = bank_i,\
+	   .index = index_i}
+
+struct ec_sensor_info {
+	char label[MAX_SENSOR_LABEL_LENGTH];
+	enum hwmon_sensor_types type;
+	struct asus_wmi_ec_sensor_address addr;
+};
+
+#define EC_SENSOR(sensor_label, sensor_type, size, bank, index) \
+	{ .label = sensor_label,\
+	.type = sensor_type, \
+	.addr = MAKE_SENSOR_ADDRESS(size, bank, index) \
+	}
+
+enum known_ec_sensor {
+	SENSOR_TEMP_CHIPSET,
+	SENSOR_TEMP_CPU,
+	SENSOR_TEMP_MB,
+	SENSOR_TEMP_T_SENSOR,
+	SENSOR_TEMP_VRM,
+	SENSOR_FAN_CPU_OPT,
+	SENSOR_FAN_CHIPSET,
+	SENSOR_FAN_WATER_FLOW,
+	SENSOR_CURR_CPU,
+	SENSOR_TEMP_WATER_IN,
+	SENSOR_TEMP_WATER_OUT,
+	SENSOR_MAX
+};
+
+/*
+ * All the known sensors for ASUS EC controllers
+ */
+static const struct ec_sensor_info known_ec_sensors[] = {
+	[SENSOR_TEMP_CHIPSET] = EC_SENSOR("Chipset", hwmon_temp, 1, 0x00, 0x3a),
+	[SENSOR_TEMP_CPU] = EC_SENSOR("CPU", hwmon_temp, 1, 0x00, 0x3b),
+	[SENSOR_TEMP_MB] = EC_SENSOR("Motherboard", hwmon_temp, 1, 0x00, 0x3c),
+	[SENSOR_TEMP_T_SENSOR] = EC_SENSOR("T_Sensor", hwmon_temp, 1, 0x00, 0x3d),
+	[SENSOR_TEMP_VRM] = EC_SENSOR("VRM", hwmon_temp, 1, 0x00, 0x3e),
+	[SENSOR_FAN_CPU_OPT] = EC_SENSOR("CPU_Opt", hwmon_fan, 2, 0x00, 0xb0),
+	[SENSOR_FAN_CHIPSET] = EC_SENSOR("Chipset", hwmon_fan, 2, 0x00, 0xb4),
+	[SENSOR_FAN_WATER_FLOW] = EC_SENSOR("Water_Flow", hwmon_fan, 2, 0x00, 0xbc),
+	[SENSOR_CURR_CPU] = EC_SENSOR("CPU", hwmon_curr, 1, 0x00, 0xf4),
+	[SENSOR_TEMP_WATER_IN] = EC_SENSOR("Water_In", hwmon_temp, 1, 0x01, 0x00),
+	[SENSOR_TEMP_WATER_OUT] = EC_SENSOR("Water_Out", hwmon_temp, 1, 0x01, 0x01),
+};
+
+struct asus_wmi_data {
+	const enum known_ec_sensor known_board_sensors[SENSOR_MAX + 1];
+};
+
+/* boards with EC support */
+static struct asus_wmi_data sensors_board_PW_X570_P = {
+	.known_board_sensors = {
+		SENSOR_TEMP_CHIPSET, SENSOR_TEMP_CPU, SENSOR_TEMP_MB, SENSOR_TEMP_VRM,
+		SENSOR_FAN_CHIPSET,
+		SENSOR_MAX
+	},
+};
+
+static struct asus_wmi_data sensors_board_PW_X570_A = {
+	.known_board_sensors = {
+		SENSOR_TEMP_CHIPSET, SENSOR_TEMP_CPU, SENSOR_TEMP_MB, SENSOR_TEMP_VRM,
+		SENSOR_FAN_CHIPSET,
+		SENSOR_CURR_CPU,
+		SENSOR_MAX
+	},
+};
+
+static struct asus_wmi_data sensors_board_R_C8H = {
+	.known_board_sensors = {
+		SENSOR_TEMP_CHIPSET, SENSOR_TEMP_CPU, SENSOR_TEMP_MB,
+		SENSOR_TEMP_T_SENSOR, SENSOR_TEMP_VRM,
+		SENSOR_TEMP_WATER_IN, SENSOR_TEMP_WATER_OUT,
+		SENSOR_FAN_CPU_OPT, SENSOR_FAN_CHIPSET, SENSOR_FAN_WATER_FLOW,
+		SENSOR_CURR_CPU,
+		SENSOR_MAX
+	},
+};
+
+/* Same as Hero but without chipset fan */
+static struct asus_wmi_data sensors_board_R_C8DH = {
+	.known_board_sensors = {
+		SENSOR_TEMP_CHIPSET, SENSOR_TEMP_CPU, SENSOR_TEMP_MB,
+		SENSOR_TEMP_T_SENSOR, SENSOR_TEMP_VRM,
+		SENSOR_TEMP_WATER_IN, SENSOR_TEMP_WATER_OUT,
+		SENSOR_FAN_CPU_OPT, SENSOR_FAN_WATER_FLOW,
+		SENSOR_CURR_CPU,
+		SENSOR_MAX
+	},
+};
+
+/* Same as Hero but without water */
+static struct asus_wmi_data sensors_board_R_C8F = {
+	.known_board_sensors = {
+		SENSOR_TEMP_CHIPSET, SENSOR_TEMP_CPU, SENSOR_TEMP_MB,
+		SENSOR_TEMP_T_SENSOR, SENSOR_TEMP_VRM,
+		SENSOR_FAN_CPU_OPT, SENSOR_FAN_CHIPSET,
+		SENSOR_CURR_CPU,
+		SENSOR_MAX
+	},
+};
+
+static struct asus_wmi_data sensors_board_RS_B550_E_G = {
+	.known_board_sensors = {
+		SENSOR_TEMP_CHIPSET, SENSOR_TEMP_CPU, SENSOR_TEMP_MB,
+		SENSOR_TEMP_T_SENSOR, SENSOR_TEMP_VRM,
+		SENSOR_FAN_CPU_OPT,
+		SENSOR_CURR_CPU,
+		SENSOR_MAX
+	},
+};
+
+static struct asus_wmi_data sensors_board_RS_X570_E_G = {
+	.known_board_sensors = {
+		SENSOR_TEMP_CHIPSET, SENSOR_TEMP_CPU, SENSOR_TEMP_MB,
+		SENSOR_TEMP_T_SENSOR, SENSOR_TEMP_VRM,
+		SENSOR_FAN_CHIPSET,
+		SENSOR_CURR_CPU,
+		SENSOR_MAX
+	},
+};
+
+static struct asus_wmi_data *board_sensors;
+
+static int __init asus_wmi_dmi_matched(const struct dmi_system_id *d)
+{
+	board_sensors = d->driver_data;
+	return 0;
+}
+
+#define DMI_EXACT_MATCH_ASUS_BOARD_NAME(name, sensors) \
+	{ \
+		.callback = asus_wmi_dmi_matched, \
+		.matches = { \
+			DMI_EXACT_MATCH(DMI_BOARD_VENDOR, \
+					"ASUSTeK COMPUTER INC."), \
+			DMI_EXACT_MATCH(DMI_BOARD_NAME, name), \
+		}, \
+		.driver_data = sensors, \
+	}
+
+static const struct dmi_system_id asus_wmi_ec_dmi_table[] __initconst = {
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("PRIME X570-PRO", &sensors_board_PW_X570_P),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("Pro WS X570-ACE", &sensors_board_PW_X570_A),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG CROSSHAIR VIII DARK HERO", &sensors_board_R_C8DH),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG CROSSHAIR VIII FORMULA", &sensors_board_R_C8F),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG CROSSHAIR VIII HERO", &sensors_board_R_C8H),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG STRIX B550-E GAMING", &sensors_board_RS_B550_E_G),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG STRIX X570-E GAMING", &sensors_board_RS_X570_E_G),
+	{}
+};
+MODULE_DEVICE_TABLE(dmi, asus_wmi_ec_dmi_table);
+
+struct ec_sensor {
+	enum known_ec_sensor info_index;
+	u32 cached_value;
+};
+
+/**
+ * struct asus_wmi_ec_info - sensor info.
+ * @sensors: list of sensors.
+ * @read_arg: UTF-16 string to pass to BRxx() WMI function.
+ * @read_buffer: decoded output from WMI result.
+ * @nr_sensors: number of board EC sensors.
+ * @nr_registers: number of EC registers to read (sensor might span more than
+ *                         1 register).
+ * @last_updated: in jiffies.
+ */
+struct asus_wmi_ec_info {
+	struct ec_sensor sensors[SENSOR_MAX];
+	char read_arg[((ASUS_WMI_BLOCK_READ_REGISTERS_MAX * 4) + 1) * 2];
+	u8 read_buffer[ASUS_WMI_BLOCK_READ_REGISTERS_MAX];
+	unsigned int nr_sensors;
+	unsigned int nr_registers;
+	unsigned long last_updated;
+};
+
+struct asus_wmi_sensors {
+	/* lock access to instrnal cache */
+	struct mutex lock;
+	struct asus_wmi_ec_info ec;
+};
+
+static int asus_wmi_ec_fill_board_sensors(struct asus_wmi_ec_info *ec)
+{
+	const enum known_ec_sensor *bsi;
+	struct ec_sensor *s = ec->sensors;
+	int i;
+
+	if (!board_sensors)
+		return -ENODEV;
+
+	bsi = board_sensors->known_board_sensors;
+	ec->nr_sensors = 0;
+	ec->nr_registers = 0;
+
+	for (i = 0; i < SENSOR_MAX && bsi[i] != SENSOR_MAX; i++) {
+		s[i].info_index = bsi[i];
+		s[i].cached_value = 0;
+		ec->nr_sensors++;
+		ec->nr_registers += known_ec_sensors[bsi[i]].addr.size;
+	}
+
+	return 0;
+}
+
+/*
+ * The next four functions converts to/from BRxx string argument format
+ * The format of the string is as follows:
+ * The string consists of two-byte UTF-16 characters
+ * The value of the very first byte int the string is equal to the total length
+ * of the next string in bytes, thus excluding the first two-byte character
+ * The rest of the string encodes pairs of (bank, index) pairs, where both
+ * values are byte-long (0x00 to 0xFF)
+ * Numbers are encoded as UTF-16 hex values
+ */
+static void asus_wmi_ec_decode_reply_buffer(const u8 *inp, u8 *out)
+{
+	unsigned int len = ACPI_MIN(ASUS_WMI_MAX_BUF_LEN, inp[0] / 4);
+	char buffer[ASUS_WMI_MAX_BUF_LEN * 2];
+	const char *pos = buffer;
+	const u8 *data = inp + 2;
+	unsigned int i;
+
+	utf16s_to_utf8s((wchar_t *)data, len * 2,  UTF16_LITTLE_ENDIAN, buffer, len * 2);
+
+	for (i = 0; i < len; i++, pos += 2)
+		out[i] = (hex_to_bin(pos[0]) << 4) + hex_to_bin(pos[1]);
+}
+
+static void asus_wmi_ec_encode_registers(u16 *registers, u8 len, char *out)
+{
+	char buffer[ASUS_WMI_MAX_BUF_LEN * 2];
+	char *pos = buffer;
+	unsigned int i;
+	u8 byte;
+
+	*out++ = len * 8;
+	*out++ = 0;
+
+	for (i = 0; i < len; i++) {
+		byte = registers[i] >> 8;
+		*pos = hex_asc_hi(byte);
+		pos++;
+		*pos = hex_asc_lo(byte);
+		pos++;
+		byte = registers[i];
+		*pos = hex_asc_hi(byte);
+		pos++;
+		*pos = hex_asc_lo(byte);
+		pos++;
+	}
+
+	utf8s_to_utf16s(buffer, len * 4, UTF16_LITTLE_ENDIAN, (wchar_t *)out, len * 4);
+}
+
+static void asus_wmi_ec_make_block_read_query(struct asus_wmi_ec_info *ec)
+{
+	u16 registers[ASUS_WMI_BLOCK_READ_REGISTERS_MAX];
+	const struct ec_sensor_info *si;
+	int i, j, register_idx = 0;
+
+	/*
+	 * if we can get values for all the registers in a single query,
+	 * the query will not change from call to call
+	 */
+	if (ec->nr_registers <= ASUS_WMI_BLOCK_READ_REGISTERS_MAX &&
+	    ec->read_arg[0] > 0) {
+		/* no need to update */
+		return;
+	}
+
+	for (i = 0; i < ec->nr_sensors; i++) {
+		si = &known_ec_sensors[ec->sensors[i].info_index];
+		for (j = 0; j < si->addr.size;
+		     j++, register_idx++) {
+			registers[register_idx] = (si->addr.bank << 8) + si->addr.index + j;
+		}
+	}
+
+	asus_wmi_ec_encode_registers(registers, ec->nr_registers, ec->read_arg);
+}
+
+static int asus_wmi_ec_block_read(u32 method_id, char *query, u8 *out)
+{
+	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER,
+				      NULL };
+	struct acpi_buffer input;
+	union acpi_object *obj;
+	acpi_status status;
+
+	/* the first byte of the BRxx() argument string has to be the string size */
+	input.length = (acpi_size)query[0] + 2;
+	input.pointer = query;
+	status = wmi_evaluate_method(ASUSWMI_MONITORING_GUID, 0, method_id, &input,
+				     &output);
+	if (ACPI_FAILURE(status))
+		return -EIO;
+
+	obj = output.pointer;
+	if (!obj || obj->type != ACPI_TYPE_BUFFER) {
+		if (!obj)
+			acpi_os_free(output.pointer);
+
+		return -EIO;
+	}
+	asus_wmi_ec_decode_reply_buffer(obj->buffer.pointer, out);
+	acpi_os_free(output.pointer);
+	return 0;
+}
+
+static int asus_wmi_ec_update_ec_sensors(struct asus_wmi_ec_info *ec)
+{
+	const struct ec_sensor_info *si;
+	struct ec_sensor *s;
+
+	int status;
+	u8 i_sensor, read_reg_ct;
+
+	asus_wmi_ec_make_block_read_query(ec);
+	status = asus_wmi_ec_block_read(ASUSWMI_METHODID_BLOCK_READ_EC,
+					ec->read_arg,
+					ec->read_buffer);
+	if (status)
+		return status;
+
+	read_reg_ct = 0;
+	for (i_sensor = 0; i_sensor < ec->nr_sensors; i_sensor++) {
+		s = &ec->sensors[i_sensor];
+		si = &known_ec_sensors[s->info_index];
+
+		switch (si->addr.size) {
+		case 1:
+			s->cached_value = ec->read_buffer[read_reg_ct];
+			break;
+		case 2:
+			s->cached_value = get_unaligned_be16(&ec->read_buffer[read_reg_ct]);
+			break;
+		case 4:
+			s->cached_value = get_unaligned_be32(&ec->read_buffer[read_reg_ct]);
+			break;
+		default:
+			s->cached_value =  0;
+		}
+		read_reg_ct += si->addr.size;
+	}
+	return 0;
+}
+
+static int asus_wmi_ec_scale_sensor_value(u32 value, int data_type)
+{
+	switch (data_type) {
+	case hwmon_curr:
+	case hwmon_temp:
+	case hwmon_in:
+		return value * KILO;
+	default:
+		return value;
+	}
+}
+
+static int asus_wmi_ec_find_sensor_index(const struct asus_wmi_ec_info *ec,
+					 enum hwmon_sensor_types type, int channel)
+{
+	int i;
+
+	for (i = 0; i < ec->nr_sensors; i++) {
+		if (known_ec_sensors[ec->sensors[i].info_index].type == type) {
+			if (channel == 0)
+				return i;
+
+			channel--;
+		}
+	}
+	return -EINVAL;
+}
+
+static int asus_wmi_ec_get_cached_value_or_update(int sensor_index,
+						  struct asus_wmi_sensors *state,
+						  u32 *value)
+{
+	int ret;
+
+	if (time_after(jiffies, state->ec.last_updated + HZ)) {
+		ret = asus_wmi_ec_update_ec_sensors(&state->ec);
+		if (ret)
+			return ret;
+
+		state->ec.last_updated = jiffies;
+	}
+
+	*value = state->ec.sensors[sensor_index].cached_value;
+	return 0;
+}
+
+/*
+ * Now follow the functions that implement the hwmon interface
+ */
+
+static int asus_wmi_ec_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
+				  u32 attr, int channel, long *val)
+{
+	struct asus_wmi_sensors *sensor_data = dev_get_drvdata(dev);
+	int ret, sidx, info_index;
+	u32 value = 0;
+
+	sidx = asus_wmi_ec_find_sensor_index(&sensor_data->ec, type, channel);
+	if (sidx < 0)
+		return sidx;
+
+	mutex_lock(&sensor_data->lock);
+	ret = asus_wmi_ec_get_cached_value_or_update(sidx, sensor_data, &value);
+	mutex_unlock(&sensor_data->lock);
+	if (ret)
+		return ret;
+
+	info_index = sensor_data->ec.sensors[sidx].info_index;
+	*val = asus_wmi_ec_scale_sensor_value(value,
+					      known_ec_sensors[info_index].type);
+
+	return ret;
+}
+
+static int asus_wmi_ec_hwmon_read_string(struct device *dev,
+					 enum hwmon_sensor_types type, u32 attr,
+					 int channel, const char **str)
+{
+	struct asus_wmi_sensors *sensor_data = dev_get_drvdata(dev);
+	int sensor_index;
+
+	sensor_index = asus_wmi_ec_find_sensor_index(&sensor_data->ec, type, channel);
+	*str = known_ec_sensors[sensor_data->ec.sensors[sensor_index].info_index].label;
+
+	return 0;
+}
+
+static umode_t asus_wmi_ec_hwmon_is_visible(const void *drvdata,
+					    enum hwmon_sensor_types type, u32 attr,
+					    int channel)
+{
+	int index;
+	const struct asus_wmi_sensors *sensor_data = drvdata;
+
+	index = asus_wmi_ec_find_sensor_index(&sensor_data->ec, type, channel);
+
+	return index == 0xff ? 0 : 0444;
+}
+
+static int asus_wmi_hwmon_add_chan_info(struct hwmon_channel_info *asus_wmi_hwmon_chan,
+					struct device *dev, int num,
+					enum hwmon_sensor_types type, u32 config)
+{
+	u32 *cfg;
+
+	cfg = devm_kcalloc(dev, num + 1, sizeof(*cfg), GFP_KERNEL);
+	if (!cfg)
+		return -ENOMEM;
+
+	asus_wmi_hwmon_chan->type = type;
+	asus_wmi_hwmon_chan->config = cfg;
+	memset32(cfg, config, num);
+
+	return 0;
+}
+
+static const struct hwmon_ops asus_wmi_ec_hwmon_ops = {
+	.is_visible = asus_wmi_ec_hwmon_is_visible,
+	.read = asus_wmi_ec_hwmon_read,
+	.read_string = asus_wmi_ec_hwmon_read_string,
+};
+
+static struct hwmon_chip_info asus_wmi_ec_chip_info = {
+	.ops = &asus_wmi_ec_hwmon_ops,
+};
+
+static int asus_wmi_ec_configure_sensor_setup(struct platform_device *pdev,
+					      struct asus_wmi_sensors *sensor_data)
+{
+	struct hwmon_channel_info *asus_wmi_hwmon_chan;
+	const struct hwmon_channel_info **ptr_asus_wmi_ci;
+	int nr_count[hwmon_max] = { 0 }, nr_types = 0;
+	const struct hwmon_chip_info *chip_info;
+	struct device *dev = &pdev->dev;
+	const struct ec_sensor_info *si;
+	enum hwmon_sensor_types type;
+	struct device *hwdev;
+	int i, ret;
+
+	ret = asus_wmi_ec_fill_board_sensors(&sensor_data->ec);
+	if (ret)
+		return ret;
+
+	if (!sensor_data->ec.nr_sensors)
+		return -ENODEV;
+
+	for (i = 0; i < sensor_data->ec.nr_sensors; i++) {
+		si = &known_ec_sensors[sensor_data->ec.sensors[i].info_index];
+		if (!nr_count[si->type])
+			nr_types++;
+		nr_count[si->type]++;
+	}
+
+	if (nr_count[hwmon_temp]) {
+		nr_count[hwmon_chip]++;
+		nr_types++;
+	}
+
+	asus_wmi_hwmon_chan = devm_kcalloc(dev, nr_types,
+					   sizeof(*asus_wmi_hwmon_chan),
+					   GFP_KERNEL);
+	if (!asus_wmi_hwmon_chan)
+		return -ENOMEM;
+
+	ptr_asus_wmi_ci = devm_kcalloc(dev, nr_types + 1,
+				       sizeof(*ptr_asus_wmi_ci), GFP_KERNEL);
+	if (!ptr_asus_wmi_ci)
+		return -ENOMEM;
+
+	asus_wmi_ec_chip_info.info = ptr_asus_wmi_ci;
+	chip_info = &asus_wmi_ec_chip_info;
+
+	for (type = 0; type < hwmon_max; type++) {
+		if (!nr_count[type])
+			continue;
+
+		ret = asus_wmi_hwmon_add_chan_info(asus_wmi_hwmon_chan, dev,
+						   nr_count[type], type,
+						   hwmon_attributes[type]);
+		if (ret)
+			return ret;
+
+		*ptr_asus_wmi_ci++ = asus_wmi_hwmon_chan++;
+	}
+
+	dev_dbg(&pdev->dev, "board has %d EC sensors that span %d registers",
+		sensor_data->ec.nr_sensors,
+		sensor_data->ec.nr_registers);
+
+	hwdev = devm_hwmon_device_register_with_info(dev, KBUILD_MODNAME,
+						     sensor_data, chip_info, NULL);
+
+	return PTR_ERR_OR_ZERO(hwdev);
+}
+
+static int asus_wmi_probe(struct platform_device *pdev)
+{
+	struct asus_wmi_sensors *sensor_data;
+	struct device *dev = &pdev->dev;
+
+	sensor_data = devm_kzalloc(dev, sizeof(struct asus_wmi_sensors),
+				   GFP_KERNEL);
+	if (!sensor_data)
+		return -ENOMEM;
+
+	mutex_init(&sensor_data->lock);
+
+	platform_set_drvdata(pdev, sensor_data);
+
+	/* ec init */
+	return asus_wmi_ec_configure_sensor_setup(pdev,
+						  sensor_data);
+}
+
+static struct platform_driver asus_wmi_sensors_platform_driver = {
+	.driver = {
+		.name	= "asus-wmi-sensors",
+	},
+	.probe = asus_wmi_probe,
+};
+
+static struct platform_device *sensors_pdev;
+
+static int __init asus_wmi_init(void)
+{
+	if (!dmi_check_system(asus_wmi_ec_dmi_table))
+		return -ENODEV;
+
+	sensors_pdev = platform_create_bundle(&asus_wmi_sensors_platform_driver,
+					      asus_wmi_probe,
+					      NULL, 0,
+					      NULL, 0);
+
+	return PTR_ERR_OR_ZERO(sensors_pdev);
+}
+module_init(asus_wmi_init);
+
+static void __exit asus_wmi_exit(void)
+{
+	platform_device_unregister(sensors_pdev);
+	platform_driver_unregister(&asus_wmi_sensors_platform_driver);
+}
+module_exit(asus_wmi_exit);
+
+MODULE_AUTHOR("Ed Brindley <kernel@maidavale.org>");
+MODULE_AUTHOR("Eugene Shalygin <eugene.shalygin@gmail.com>");
+MODULE_DESCRIPTION("Asus WMI Sensors Driver");
+MODULE_LICENSE("GPL");
-- 
2.33.0

[PATCH v3 2/2] hwmon: (asus_wmi_sensors) Support X370 Asus WMI.

[Denis Pauk]

Provides a Linux kernel module "asus_wmi_sensors" that provides sensor
readouts via ASUS' WMI interface present in the UEFI of
X370/X470/B450/X399 Ryzen motherboards.

Supported motherboards:
* ROG CROSSHAIR VI HERO,
* PRIME X399-A,
* PRIME X470-PRO,
* ROG CROSSHAIR VI EXTREME,
* ROG CROSSHAIR VI HERO (WI-FI AC),
* ROG CROSSHAIR VII HERO,
* ROG CROSSHAIR VII HERO (WI-FI),
* ROG STRIX B450-E GAMING,
* ROG STRIX B450-F GAMING,
* ROG STRIX B450-I GAMING,
* ROG STRIX X399-E GAMING,
* ROG STRIX X470-F GAMING,
* ROG STRIX X470-I GAMING,
* ROG ZENITH EXTREME,
* ROG ZENITH EXTREME ALPHA.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=204807
Signed-off-by: Denis Pauk <pauk.denis@gmail.com>
Co-developed-by: Ed Brindley <kernel@maidavale.org>
Signed-off-by: Ed Brindley <kernel@maidavale.org>

---
Changes in v3:
- Use MODULE_DEVICE_TABLE for match devices.
- Add documentaion for driver.

Changes in v2:
- Add module for boards with support of WMI interface returned sensor name and
  value of sensor..
---
 Documentation/hwmon/asus_wmi_sensors.rst |  62 +++
 MAINTAINERS                              |   1 +
 drivers/hwmon/Kconfig                    |  11 +
 drivers/hwmon/Makefile                   |   1 +
 drivers/hwmon/asus_wmi_sensors.c         | 635 +++++++++++++++++++++++
 5 files changed, 710 insertions(+)
 create mode 100644 Documentation/hwmon/asus_wmi_sensors.rst
 create mode 100644 drivers/hwmon/asus_wmi_sensors.c

diff --git a/Documentation/hwmon/asus_wmi_sensors.rst b/Documentation/hwmon/asus_wmi_sensors.rst
new file mode 100644
index 000000000000..9526239df163
--- /dev/null
+++ b/Documentation/hwmon/asus_wmi_sensors.rst
@@ -0,0 +1,62 @@
+Kernel driver asus-wmi-sensors
+=================================
+
+Supported boards:
+ * PRIME X399-A,
+ * PRIME X470-PRO,
+ * ROG CROSSHAIR VI EXTREME,
+ * ROG CROSSHAIR VI HERO,
+ * ROG CROSSHAIR VI HERO (WI-FI AC),
+ * ROG CROSSHAIR VII HERO,
+ * ROG CROSSHAIR VII HERO (WI-FI),
+ * ROG STRIX B450-E GAMING,
+ * ROG STRIX B450-F GAMING,
+ * ROG STRIX B450-I GAMING,
+ * ROG STRIX X399-E GAMING,
+ * ROG STRIX X470-F GAMING,
+ * ROG STRIX X470-I GAMING,
+ * ROG ZENITH EXTREME,
+ * ROG ZENITH EXTREME ALPHA.
+
+Authors:
+        Ed Brindley <kernel@maidavale.org>
+
+Description:
+------------
+ASUS mainboards publish hardware monitoring information via WMI interface.
+
+ASUS WMI interface provides a methods to get list of sensors and values of
+such, which is utilized by this driver to publish those sensor readings to the
+HWMON system. The driver is aware of and reads the following sensors:
+ * CPU Core Voltage,
+ * CPU SOC Voltage,
+ * DRAM Voltage,
+ * VDDP Voltage,
+ * 1.8V PLL Voltage,
+ * +12V Voltage,
+ * +5V Voltage,
+ * 3VSB Voltage,
+ * VBAT Voltage,
+ * AVCC3 Voltage,
+ * SB 1.05V Voltage,
+ * CPU Core Voltage,
+ * CPU SOC Voltage,
+ * DRAM Voltage,
+ * CPU Fan RPM,
+ * Chassis Fan 1 RPM,
+ * Chassis Fan 2 RPM,
+ * Chassis Fan 3 RPM,
+ * HAMP Fan RPM,
+ * Water Pump RPM,
+ * CPU OPT RPM,
+ * Water Flow RPM,
+ * AIO Pump RPM,
+ * CPU Temperature,
+ * CPU Socket Temperature,
+ * Motherboard Temperature,
+ * Chipset Temperature,
+ * Tsensor 1 Temperature,
+ * CPU VRM Temperature,
+ * Water In,
+ * Water Out,
+ * CPU VRM Output Current.
diff --git a/MAINTAINERS b/MAINTAINERS
index 05448435991d..46036c184330 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2943,6 +2943,7 @@ M:	Denis Pauk <pauk.denis@gmail.com>
 L:	linux-hwmon@vger.kernel.org
 S:	Maintained
 F:	drivers/hwmon/asus_wmi_ec_sensors.c
+F:	drivers/hwmon/asus_wmi_sensors.c
 
 ASUS WIRELESS RADIO CONTROL DRIVER
 M:	João Paulo Rechi Vita <jprvita@gmail.com>
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 430a438432a0..461328c4b00a 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -2215,6 +2215,17 @@ config SENSORS_ATK0110
 	  This driver can also be built as a module. If so, the module
 	  will be called asus_atk0110.
 
+config SENSORS_ASUS_WMI
+	tristate "ASUS WMI X370/X470/B450/X399"
+	help
+	  If you say yes here you get support for the ACPI hardware monitoring
+	  interface found in X370/X470/B450/X399 ASUS motherboards. This driver
+	  will provide readings of fans, voltages and temperatures through the system
+	  firmware.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called asus_wmi_sensors.
+
 config SENSORS_ASUS_WMI_EC
 	tristate "ASUS WMI B550/X570"
 	help
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index aae2ff5c7335..656a6191a0f8 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_HWMON_VID)		+= hwmon-vid.o
 # APCI drivers
 obj-$(CONFIG_SENSORS_ACPI_POWER) += acpi_power_meter.o
 obj-$(CONFIG_SENSORS_ATK0110)	+= asus_atk0110.o
+obj-$(CONFIG_SENSORS_ASUS_WMI)	+= asus_wmi_sensors.o
 obj-$(CONFIG_SENSORS_ASUS_WMI_EC)	+= asus_wmi_ec_sensors.o
 
 # Native drivers
diff --git a/drivers/hwmon/asus_wmi_sensors.c b/drivers/hwmon/asus_wmi_sensors.c
new file mode 100644
index 000000000000..ac6a9955e886
--- /dev/null
+++ b/drivers/hwmon/asus_wmi_sensors.c
@@ -0,0 +1,635 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * HWMON driver for ASUS motherboards that provides sensor readouts via WMI
+ * interface present in the UEFI of the X370/X470/B450/X399 Ryzen motherboards.
+ *
+ * Copyright (C) 2018-2019 Ed Brindley <kernel@maidavale.org>
+ *
+ * WMI interface provides:
+ * CPU Core Voltage,
+ * CPU SOC Voltage,
+ * DRAM Voltage,
+ * VDDP Voltage,
+ * 1.8V PLL Voltage,
+ * +12V Voltage,
+ * +5V Voltage,
+ * 3VSB Voltage,
+ * VBAT Voltage,
+ * AVCC3 Voltage,
+ * SB 1.05V Voltage,
+ * CPU Core Voltage,
+ * CPU SOC Voltage,
+ * DRAM Voltage,
+ * CPU Fan RPM,
+ * Chassis Fan 1 RPM,
+ * Chassis Fan 2 RPM,
+ * Chassis Fan 3 RPM,
+ * HAMP Fan RPM,
+ * Water Pump RPM,
+ * CPU OPT RPM,
+ * Water Flow RPM,
+ * AIO Pump RPM,
+ * CPU Temperature,
+ * CPU Socket Temperature,
+ * Motherboard Temperature,
+ * Chipset Temperature,
+ * Tsensor 1 Temperature,
+ * CPU VRM Temperature,
+ * Water In,
+ * Water Out,
+ * CPU VRM Output Current.
+ *
+ */
+#include <linux/acpi.h>
+#include <linux/dmi.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/init.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/units.h>
+#include <linux/wmi.h>
+
+#define ASUSWMI_MONITORING_GUID		"466747A0-70EC-11DE-8A39-0800200C9A66"
+#define ASUSWMI_METHODID_GET_VALUE	0x52574543
+#define ASUSWMI_METHODID_UPDATE_BUFFER	0x51574543
+#define ASUSWMI_METHODID_GET_INFO	0x50574543
+#define ASUSWMI_METHODID_GET_NUMBER		0x50574572
+#define ASUSWMI_METHODID_GET_VERSION		0x50574574
+
+#define ASUS_WMI_MAX_STR_SIZE	32
+
+#define DMI_EXACT_MATCH_ASUS_BOARD_NAME(name) \
+	{ \
+		.matches = { \
+			DMI_EXACT_MATCH(DMI_BOARD_VENDOR, \
+					"ASUSTeK COMPUTER INC."), \
+			DMI_EXACT_MATCH(DMI_BOARD_NAME, name), \
+		}, \
+	}
+
+static const struct dmi_system_id asus_wmi_dmi_table[] __initconst = {
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("PRIME X399-A"),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("PRIME X470-PRO"),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG CROSSHAIR VI EXTREME"),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG CROSSHAIR VI HERO"),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG CROSSHAIR VI HERO (WI-FI AC)"),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG CROSSHAIR VII HERO"),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG CROSSHAIR VII HERO (WI-FI)"),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG STRIX B450-E GAMING"),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG STRIX B450-F GAMING"),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG STRIX B450-I GAMING"),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG STRIX X399-E GAMING"),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG STRIX X470-F GAMING"),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG STRIX X470-I GAMING"),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG ZENITH EXTREME"),
+	DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG ZENITH EXTREME ALPHA"),
+	{}
+};
+MODULE_DEVICE_TABLE(dmi, asus_wmi_dmi_table);
+
+enum asus_wmi_sensor_class {
+	VOLTAGE = 0x0,
+	TEMPERATURE_C = 0x1,
+	FAN_RPM = 0x2,
+	CURRENT = 0x3,
+	WATER_FLOW = 0x4,
+};
+
+enum asus_wmi_location {
+	CPU = 0x0,
+	CPU_SOC = 0x1,
+	DRAM = 0x2,
+	MOTHERBOARD = 0x3,
+	CHIPSET = 0x4,
+	AUX = 0x5,
+	VRM = 0x6,
+	COOLER = 0x7
+};
+
+enum asus_wmi_type {
+	SIGNED_INT = 0x0,
+	UNSIGNED_INT = 0x1,
+	SCALED = 0x3,
+};
+
+enum asus_wmi_source {
+	SIO = 0x1,
+	EC = 0x2
+};
+
+static enum hwmon_sensor_types asus_data_types[] = {
+	[VOLTAGE] = hwmon_in,
+	[TEMPERATURE_C] = hwmon_temp,
+	[FAN_RPM] = hwmon_fan,
+	[CURRENT] = hwmon_curr,
+	[WATER_FLOW] = hwmon_fan,
+};
+
+static u32 hwmon_attributes[] = {
+	[hwmon_chip] = HWMON_C_REGISTER_TZ,
+	[hwmon_temp] = HWMON_T_INPUT | HWMON_T_LABEL,
+	[hwmon_in] = HWMON_I_INPUT | HWMON_I_LABEL,
+	[hwmon_curr] = HWMON_C_INPUT | HWMON_C_LABEL,
+	[hwmon_fan] = HWMON_F_INPUT | HWMON_F_LABEL,
+};
+
+/**
+ * struct asus_wmi_sensor_info - sensor info.
+ * @id: sensor id.
+ * @data_type: sensor class e.g. voltage, temp etc.
+ * @location: sensor location.
+ * @name: sensor name.
+ * @source: sensor source.
+ * @type: sensor type signed, unsigned etc.
+ * @cached_value: cached sensor value.
+ */
+struct asus_wmi_sensor_info {
+	u32 id;
+	int data_type;
+	int location;
+	char name[ASUS_WMI_MAX_STR_SIZE];
+	int source;
+	int type;
+	u32 cached_value;
+};
+
+struct asus_wmi_wmi_info {
+	u8 buffer;
+	unsigned long source_last_updated[3];	/* in jiffies */
+	int sensor_count;
+
+	const struct asus_wmi_sensor_info **info[hwmon_max];
+	struct asus_wmi_sensor_info **info_by_id;
+};
+
+struct asus_wmi_sensors {
+	/* lock access to instrnal cache */
+	struct mutex lock;
+	struct asus_wmi_wmi_info wmi;
+};
+
+/*
+ * Universal method for calling WMI method
+ */
+static int asus_wmi_call_method(u32 method_id, u32 *args, struct acpi_buffer *output)
+{
+	struct acpi_buffer input = {(acpi_size) sizeof(*args), args };
+	acpi_status status;
+
+	status = wmi_evaluate_method(ASUSWMI_MONITORING_GUID, 0, method_id, &input, output);
+	if (ACPI_FAILURE(status))
+		return -EIO;
+
+	return 0;
+}
+
+/*
+ * Gets the version of the ASUS sensors interface implemented
+ */
+static int asus_wmi_get_version(u32 *version)
+{
+	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+	u32 args[] = {0, 0, 0};
+	union acpi_object *obj;
+	int err;
+
+	err = asus_wmi_call_method(ASUSWMI_METHODID_GET_VERSION, args, &output);
+	if (err)
+		return err;
+
+	obj = output.pointer;
+	if (!obj || obj->type != ACPI_TYPE_INTEGER)
+		return -EIO;
+
+	*version = obj->integer.value;
+
+	return 0;
+}
+
+/*
+ * Gets the number of sensor items
+ */
+static int asus_wmi_get_item_count(u32 *count)
+{
+	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+	u32 args[] = {0, 0, 0};
+	union acpi_object *obj;
+	int err;
+
+	err = asus_wmi_call_method(ASUSWMI_METHODID_GET_NUMBER, args, &output);
+	if (err)
+		return err;
+
+	obj = output.pointer;
+	if (!obj || obj->type != ACPI_TYPE_INTEGER)
+		return -EIO;
+
+	*count = obj->integer.value;
+
+	return 0;
+}
+
+static int asus_wmi_hwmon_add_chan_info(struct hwmon_channel_info *asus_wmi_hwmon_chan,
+					struct device *dev, int num,
+					enum hwmon_sensor_types type, u32 config)
+{
+	u32 *cfg;
+
+	cfg = devm_kcalloc(dev, num + 1, sizeof(*cfg), GFP_KERNEL);
+	if (!cfg)
+		return -ENOMEM;
+
+	asus_wmi_hwmon_chan->type = type;
+	asus_wmi_hwmon_chan->config = cfg;
+	memset32(cfg, config, num);
+
+	return 0;
+}
+
+/*
+ * For a given sensor item returns details e.g. type (voltage/temperature/fan speed etc), bank etc
+ */
+static int asus_wmi_sensor_info(int index, struct asus_wmi_sensor_info *s)
+{
+	union acpi_object name_obj, data_type_obj, location_obj, source_obj, type_obj;
+	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+	u32 args[] = {index, 0};
+	union acpi_object *obj;
+	int err;
+
+	err = asus_wmi_call_method(ASUSWMI_METHODID_GET_INFO, args, &output);
+	if (err)
+		return err;
+
+	s->id = index;
+
+	obj = output.pointer;
+	if (!obj || obj->type != ACPI_TYPE_PACKAGE)
+		return -EIO;
+
+	if (obj->package.count != 5)
+		return 1;
+
+	name_obj = obj->package.elements[0];
+
+	if (name_obj.type != ACPI_TYPE_STRING)
+		return 1;
+
+	strncpy(s->name, name_obj.string.pointer, sizeof(s->name) - 1);
+
+	data_type_obj = obj->package.elements[1];
+
+	if (data_type_obj.type != ACPI_TYPE_INTEGER)
+		return 1;
+
+	s->data_type = data_type_obj.integer.value;
+
+	location_obj = obj->package.elements[2];
+
+	if (location_obj.type != ACPI_TYPE_INTEGER)
+		return 1;
+
+	s->location = location_obj.integer.value;
+
+	source_obj = obj->package.elements[3];
+
+	if (source_obj.type != ACPI_TYPE_INTEGER)
+		return 1;
+
+	s->source = source_obj.integer.value;
+
+	type_obj = obj->package.elements[4];
+
+	if (type_obj.type != ACPI_TYPE_INTEGER)
+		return 1;
+
+	s->type = type_obj.integer.value;
+
+	return 0;
+}
+
+static int asus_wmi_update_buffer(u8 source)
+{
+	u32 args[] = {source, 0};
+	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+
+	return asus_wmi_call_method(ASUSWMI_METHODID_UPDATE_BUFFER, args, &output);
+}
+
+static int asus_wmi_get_sensor_value(u8 index, u32 *value)
+{
+	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+	u32 args[] = {index, 0};
+	union acpi_object *obj;
+	int err;
+
+	err = asus_wmi_call_method(ASUSWMI_METHODID_GET_VALUE, args, &output);
+	if (err)
+		return err;
+
+	obj = output.pointer;
+	if (!obj || obj->type != ACPI_TYPE_INTEGER)
+		return -EIO;
+
+	*value = obj->integer.value;
+
+	return 0;
+}
+
+static void asus_wmi_update_values_for_source(u8 source, struct asus_wmi_sensors *sensor_data)
+{
+	int ret = 0;
+	int value = 0;
+	int i;
+	struct asus_wmi_sensor_info *sensor;
+
+	for (i = 0; i < sensor_data->wmi.sensor_count; i++) {
+		sensor = sensor_data->wmi.info_by_id[i];
+		if (sensor && sensor->source == source) {
+			ret = asus_wmi_get_sensor_value(sensor->id, &value);
+			if (!ret)
+				sensor->cached_value = value;
+		}
+	}
+}
+
+static int asus_wmi_scale_sensor_value(u32 value, int data_type)
+{
+	/* FAN_RPM and WATER_FLOW don't need scaling */
+	switch (data_type) {
+	case VOLTAGE:
+		return DIV_ROUND_CLOSEST(value, 1000);
+	case TEMPERATURE_C:
+		return value * 1000;
+	case CURRENT:
+		return value * 1000;
+	}
+	return value;
+}
+
+static int asus_wmi_get_cached_value_or_update(const struct asus_wmi_sensor_info *sensor,
+					       struct asus_wmi_sensors *sensor_data,
+					       u32 *value)
+{
+	int ret;
+
+	if (time_after(jiffies, sensor_data->wmi.source_last_updated[sensor->source] + HZ)) {
+		ret = asus_wmi_update_buffer(sensor->source);
+		if (ret)
+			return -EIO;
+
+		sensor_data->wmi.buffer = sensor->source;
+
+		asus_wmi_update_values_for_source(sensor->source, sensor_data);
+		sensor_data->wmi.source_last_updated[sensor->source] = jiffies;
+	}
+
+	*value = sensor->cached_value;
+	return 0;
+}
+
+/*
+ * Now follow the functions that implement the hwmon interface
+ */
+
+static int asus_wmi_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
+			       u32 attr, int channel, long *val)
+{
+	int ret;
+	u32 value = 0;
+	const struct asus_wmi_sensor_info *sensor;
+
+	struct asus_wmi_sensors *sensor_data = dev_get_drvdata(dev);
+
+	sensor = *(sensor_data->wmi.info[type] + channel);
+
+	mutex_lock(&sensor_data->lock);
+	ret = asus_wmi_get_cached_value_or_update(sensor, sensor_data, &value);
+	mutex_unlock(&sensor_data->lock);
+	if (!ret)
+		*val = asus_wmi_scale_sensor_value(value, sensor->data_type);
+
+	return ret;
+}
+
+static int asus_wmi_hwmon_read_string(struct device *dev,
+				      enum hwmon_sensor_types type, u32 attr,
+				      int channel, const char **str)
+{
+	const struct asus_wmi_sensor_info *sensor;
+	struct asus_wmi_sensors *sensor_data = dev_get_drvdata(dev);
+
+	sensor = *(sensor_data->wmi.info[type] + channel);
+	*str = sensor->name;
+
+	return 0;
+}
+
+static umode_t asus_wmi_hwmon_is_visible(const void *drvdata,
+					 enum hwmon_sensor_types type, u32 attr,
+					 int channel)
+{
+	const struct asus_wmi_sensor_info *sensor;
+	const struct asus_wmi_sensors *sensor_data = drvdata;
+
+	sensor = *(sensor_data->wmi.info[type] + channel);
+	if (sensor && sensor->name)
+		return 0444;
+
+	return 0;
+}
+
+static const struct hwmon_ops asus_wmi_hwmon_ops = {
+	.is_visible = asus_wmi_hwmon_is_visible,
+	.read = asus_wmi_hwmon_read,
+	.read_string = asus_wmi_hwmon_read_string,
+};
+
+static struct hwmon_chip_info asus_wmi_chip_info = {
+	.ops = &asus_wmi_hwmon_ops,
+	.info = NULL,
+};
+
+static int asus_wmi_configure_sensor_setup(struct platform_device *pdev,
+					   struct asus_wmi_sensors *sensor_data)
+{
+	int err;
+	int i, idx;
+	int nr_count[hwmon_max] = {0}, nr_types = 0;
+	struct device *hwdev;
+	struct device *dev = &pdev->dev;
+	struct hwmon_channel_info *asus_wmi_hwmon_chan;
+	struct asus_wmi_sensor_info *temp_sensor;
+	enum hwmon_sensor_types type;
+	const struct hwmon_channel_info **ptr_asus_wmi_ci;
+	const struct hwmon_chip_info *chip_info;
+
+	sensor_data->wmi.buffer = -1;
+	temp_sensor = devm_kcalloc(dev, 1, sizeof(*temp_sensor), GFP_KERNEL);
+	if (!temp_sensor)
+		return -ENOMEM;
+
+	for (i = 0; i < sensor_data->wmi.sensor_count; i++) {
+		err = asus_wmi_sensor_info(i, temp_sensor);
+		if (err)
+			return -EINVAL;
+
+		switch (temp_sensor->data_type) {
+		case TEMPERATURE_C:
+		case VOLTAGE:
+		case CURRENT:
+		case FAN_RPM:
+		case WATER_FLOW:
+			type = asus_data_types[temp_sensor->data_type];
+			if (!nr_count[type])
+				nr_types++;
+			nr_count[type]++;
+			break;
+		}
+	}
+
+	if (nr_count[hwmon_temp])
+		nr_count[hwmon_chip]++, nr_types++;
+
+	asus_wmi_hwmon_chan = devm_kcalloc(dev, nr_types,
+					   sizeof(*asus_wmi_hwmon_chan),
+					   GFP_KERNEL);
+	if (!asus_wmi_hwmon_chan)
+		return -ENOMEM;
+
+	ptr_asus_wmi_ci = devm_kcalloc(dev, nr_types + 1,
+				       sizeof(*ptr_asus_wmi_ci), GFP_KERNEL);
+	if (!ptr_asus_wmi_ci)
+		return -ENOMEM;
+
+	asus_wmi_chip_info.info = ptr_asus_wmi_ci;
+	chip_info = &asus_wmi_chip_info;
+
+	sensor_data->wmi.info_by_id = devm_kcalloc(dev, sensor_data->wmi.sensor_count,
+						   sizeof(*sensor_data->wmi.info_by_id),
+						   GFP_KERNEL);
+
+	if (!sensor_data->wmi.info_by_id)
+		return -ENOMEM;
+
+	for (type = 0; type < hwmon_max; type++) {
+		if (!nr_count[type])
+			continue;
+
+		asus_wmi_hwmon_add_chan_info(asus_wmi_hwmon_chan, dev,
+					     nr_count[type], type,
+					     hwmon_attributes[type]);
+		*ptr_asus_wmi_ci++ = asus_wmi_hwmon_chan++;
+
+		sensor_data->wmi.info[type] = devm_kcalloc(dev,
+							   nr_count[type],
+							   sizeof(*sensor_data->wmi.info),
+							   GFP_KERNEL);
+		if (!sensor_data->wmi.info[type])
+			return -ENOMEM;
+	}
+
+	for (i = sensor_data->wmi.sensor_count - 1; i >= 0 ; i--) {
+		temp_sensor = devm_kzalloc(dev, sizeof(*temp_sensor), GFP_KERNEL);
+		if (!temp_sensor)
+			return -ENOMEM;
+
+		err = asus_wmi_sensor_info(i, temp_sensor);
+		if (err)
+			continue;
+
+		switch (temp_sensor->data_type) {
+		case TEMPERATURE_C:
+		case VOLTAGE:
+		case CURRENT:
+		case FAN_RPM:
+		case WATER_FLOW:
+			type = asus_data_types[temp_sensor->data_type];
+			idx = --nr_count[type];
+			*(sensor_data->wmi.info[type] + idx) = temp_sensor;
+			sensor_data->wmi.info_by_id[i] = temp_sensor;
+			break;
+		}
+	}
+
+	dev_dbg(&pdev->dev, "board has %d sensors",
+		sensor_data->wmi.sensor_count);
+
+	hwdev = devm_hwmon_device_register_with_info(dev, KBUILD_MODNAME,
+						     sensor_data, chip_info, NULL);
+
+	return PTR_ERR_OR_ZERO(hwdev);
+}
+
+static int asus_wmi_probe(struct platform_device *pdev)
+{
+	struct asus_wmi_sensors *sensor_data;
+	struct device *dev = &pdev->dev;
+	u32 version = 0;
+
+	sensor_data = devm_kzalloc(dev, sizeof(struct asus_wmi_sensors),
+				   GFP_KERNEL);
+	if (!sensor_data)
+		return -ENOMEM;
+
+	if (!wmi_has_guid(ASUSWMI_MONITORING_GUID))
+		return -ENODEV;
+
+	if (asus_wmi_get_version(&version))
+		return -ENODEV;
+
+	if (asus_wmi_get_item_count(&sensor_data->wmi.sensor_count))
+		return -ENODEV;
+
+	if (sensor_data->wmi.sensor_count  <= 0 || version < 2) {
+		dev_info(dev, "version: %u with %d sensors is unsupported\n",
+			 version, sensor_data->wmi.sensor_count);
+
+		return -ENODEV;
+	}
+
+	mutex_init(&sensor_data->lock);
+
+	platform_set_drvdata(pdev, sensor_data);
+
+	return asus_wmi_configure_sensor_setup(pdev,
+					       sensor_data);
+}
+
+static struct platform_driver asus_wmi_sensors_platform_driver = {
+	.driver = {
+		.name	= "asus-wmi-sensors",
+	},
+	.probe = asus_wmi_probe,
+};
+
+static struct platform_device *sensors_pdev;
+
+static int __init asus_wmi_init(void)
+{
+	if (!dmi_check_system(asus_wmi_dmi_table))
+		return -ENODEV;
+
+	sensors_pdev = platform_create_bundle(&asus_wmi_sensors_platform_driver,
+					      asus_wmi_probe,
+					      NULL, 0,
+					      NULL, 0);
+
+	return PTR_ERR_OR_ZERO(sensors_pdev);
+}
+module_init(asus_wmi_init);
+
+static void __exit asus_wmi_exit(void)
+{
+	platform_device_unregister(sensors_pdev);
+	platform_driver_unregister(&asus_wmi_sensors_platform_driver);
+}
+module_exit(asus_wmi_exit);
+
+MODULE_AUTHOR("Ed Brindley <kernel@maidavale.org>");
+MODULE_DESCRIPTION("Asus WMI Sensors Driver");
+MODULE_LICENSE("GPL");
-- 
2.33.0

Re: [PATCH v3 2/2] hwmon: (asus_wmi_sensors) Support X370 Asus WMI.

[Thomas Weißschuh]

Hi,

for WMI drivers the list platform-driver-x86@vger.kernel.org should probably be
on CC too.
Also all other WMI drivers, even for hwmon stuff are located in
drivers/platform/x86 so it may be better to put it there, too.

One comment inline.

On 2021-10-10T12:52+0300, Denis Pauk wrote:
> +static struct platform_driver asus_wmi_sensors_platform_driver = {
> +	.driver = {
> +		.name	= "asus-wmi-sensors",
> +	},
> +	.probe = asus_wmi_probe,
> +};
> +
> +static struct platform_device *sensors_pdev;
> +
> +static int __init asus_wmi_init(void)
> +{
> +	if (!dmi_check_system(asus_wmi_dmi_table))
> +		return -ENODEV;
> +
> +	sensors_pdev = platform_create_bundle(&asus_wmi_sensors_platform_driver,
> +					      asus_wmi_probe,
> +					      NULL, 0,
> +					      NULL, 0);
> +
> +	return PTR_ERR_OR_ZERO(sensors_pdev);
> +}
> +module_init(asus_wmi_init);
> +
> +static void __exit asus_wmi_exit(void)
> +{
> +	platform_device_unregister(sensors_pdev);
> +	platform_driver_unregister(&asus_wmi_sensors_platform_driver);
> +}
> +module_exit(asus_wmi_exit);

This should bind to the WMI bus instead of being a platform device.
See drivers/platform/x86/gigabyte-wmi.c

(Some goes also for the other driver)

Thomas

Re: [PATCH v3 2/2] hwmon: (asus_wmi_sensors) Support X370 Asus WMI.

[Guenter Roeck]

On 10/10/21 3:20 AM, Thomas Weißschuh wrote:
> Hi,
> 
> for WMI drivers the list platform-driver-x86@vger.kernel.org should probably be
> on CC too.
> Also all other WMI drivers, even for hwmon stuff are located in
> drivers/platform/x86 so it may be better to put it there, too.
> 

Not really. If any of those other drivers are pure hwmon drivers, they
should reside in drivers/hwmon instead. And, yes, that really includes
the gigabyte-wmi driver. We don't have arbitrary drivers in drivers/pci
either just because they are drivers for pci devices.

Guenter

> One comment inline.
> 
> On 2021-10-10T12:52+0300, Denis Pauk wrote:
>> +static struct platform_driver asus_wmi_sensors_platform_driver = {
>> +	.driver = {
>> +		.name	= "asus-wmi-sensors",
>> +	},
>> +	.probe = asus_wmi_probe,
>> +};
>> +
>> +static struct platform_device *sensors_pdev;
>> +
>> +static int __init asus_wmi_init(void)
>> +{
>> +	if (!dmi_check_system(asus_wmi_dmi_table))
>> +		return -ENODEV;
>> +
>> +	sensors_pdev = platform_create_bundle(&asus_wmi_sensors_platform_driver,
>> +					      asus_wmi_probe,
>> +					      NULL, 0,
>> +					      NULL, 0);
>> +
>> +	return PTR_ERR_OR_ZERO(sensors_pdev);
>> +}
>> +module_init(asus_wmi_init);
>> +
>> +static void __exit asus_wmi_exit(void)
>> +{
>> +	platform_device_unregister(sensors_pdev);
>> +	platform_driver_unregister(&asus_wmi_sensors_platform_driver);
>> +}
>> +module_exit(asus_wmi_exit);
> 
> This should bind to the WMI bus instead of being a platform device.
> See drivers/platform/x86/gigabyte-wmi.c
> 
> (Some goes also for the other driver)
> 
> Thomas
> 

Re: [PATCH v3 0/2] Update ASUS WMI supported boards

[Pali Rohár]

On Sunday 10 October 2021 12:52:13 Denis Pauk wrote:
> Add support by WMI interface privided by Asus for B550/X570 boards: 
...
> Add support by WMI interface privided by Asus for X370/X470/
> B450/X399 boards:
...
> BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=204807

Hello! Could you provide (at least into bug tracker) MOF definitions of
WMI functions? If there are are any issues with driver, definitions of
API, functions and buffers could help.

Re: [PATCH v3 2/2] hwmon: (asus_wmi_sensors) Support X370 Asus WMI.

[Thomas Weißschuh]

On 2021-10-10T06:38-0700, Guenter Roeck wrote:
> On 10/10/21 3:20 AM, Thomas Weißschuh wrote:
> > Hi,
> > 
> > for WMI drivers the list platform-driver-x86@vger.kernel.org should probably be
> > on CC too.
> > Also all other WMI drivers, even for hwmon stuff are located in
> > drivers/platform/x86 so it may be better to put it there, too.
> > 
> 
> Not really. If any of those other drivers are pure hwmon drivers, they
> should reside in drivers/hwmon instead. And, yes, that really includes
> the gigabyte-wmi driver. We don't have arbitrary drivers in drivers/pci
> either just because they are drivers for pci devices.

Fair enough.
I suppose it would be too much churn to move gigabyte-wmi to
hwmon now though, correct?

Having the platform-driver-x86 on Cc would still be useful as they can provide
guidance about using the ACPI/WMI/platform APIs.

For example by using the WMI bus as mentioned in my other mail would allow
to completely remove the manually maintained DMI list and instead directly bind
to the WMI GUID for any device that supports this GUID.
(This is possible as this WMI API seems to be self-describing, so all
specific parameters can be discovered by the driver)

Thomas

Re: [PATCH v3 2/2] hwmon: (asus_wmi_sensors) Support X370 Asus WMI.

[Guenter Roeck]

On 10/10/21 7:10 AM, Thomas Weißschuh wrote:
> On 2021-10-10T06:38-0700, Guenter Roeck wrote:
>> On 10/10/21 3:20 AM, Thomas Weißschuh wrote:
>>> Hi,
>>>
>>> for WMI drivers the list platform-driver-x86@vger.kernel.org should probably be
>>> on CC too.
>>> Also all other WMI drivers, even for hwmon stuff are located in
>>> drivers/platform/x86 so it may be better to put it there, too.
>>>
>>
>> Not really. If any of those other drivers are pure hwmon drivers, they
>> should reside in drivers/hwmon instead. And, yes, that really includes
>> the gigabyte-wmi driver. We don't have arbitrary drivers in drivers/pci
>> either just because they are drivers for pci devices.
> 
> Fair enough.
> I suppose it would be too much churn to move gigabyte-wmi to
> hwmon now though, correct?
> 

Is it ? I don't recall the reason why it was added to drivers/platform/x86
in the first place. I see other single-use wmi drivers in that directory
as well (eg xiaomi-wmi, which should be in input). Is there some unwritten
rule stating that all wmi drivers shall reside in drivers/platform/x86,
no matter what subsystem they touch ?

> Having the platform-driver-x86 on Cc would still be useful as they can provide
> guidance about using the ACPI/WMI/platform APIs.
> 

Sure, but that is unrelated to the driver location, and the opposite argument
can be made as well (that drivers implementing subsystem code should be reviewed
by subsystem maintainers). That is a much stronger argument in my opinion.

Guenter

> For example by using the WMI bus as mentioned in my other mail would allow
> to completely remove the manually maintained DMI list and instead directly bind
> to the WMI GUID for any device that supports this GUID.
> (This is possible as this WMI API seems to be self-describing, so all
> specific parameters can be discovered by the driver)
> 
> Thomas
> 

Re: [PATCH v3 2/2] hwmon: (asus_wmi_sensors) Support X370 Asus WMI.

[Thomas Weißschuh]

On 2021-10-10T07:56-0700, Guenter Roeck wrote:
> On 10/10/21 7:10 AM, Thomas Weißschuh wrote:
> > On 2021-10-10T06:38-0700, Guenter Roeck wrote:
> > > On 10/10/21 3:20 AM, Thomas Weißschuh wrote:
> > > > Hi,
> > > > 
> > > > for WMI drivers the list platform-driver-x86@vger.kernel.org should probably be
> > > > on CC too.
> > > > Also all other WMI drivers, even for hwmon stuff are located in
> > > > drivers/platform/x86 so it may be better to put it there, too.
> > > > 
> > > 
> > > Not really. If any of those other drivers are pure hwmon drivers, they
> > > should reside in drivers/hwmon instead. And, yes, that really includes
> > > the gigabyte-wmi driver. We don't have arbitrary drivers in drivers/pci
> > > either just because they are drivers for pci devices.
> > 
> > Fair enough.
> > I suppose it would be too much churn to move gigabyte-wmi to
> > hwmon now though, correct?
> > 
> 
> Is it ? I don't recall the reason why it was added to drivers/platform/x86
> in the first place. I see other single-use wmi drivers in that directory
> as well (eg xiaomi-wmi, which should be in input). Is there some unwritten
> rule stating that all wmi drivers shall reside in drivers/platform/x86,
> no matter what subsystem they touch ?

There was no specific reason. I saw all the other WMI drivers in
drivers/platform/x86 and added mine there and sent it to the recipients as
reported by get_maintainer.pl.

You mentioned that it could move to hwmon but Hans said there are other
single-use wmi drivers in drivers/platform/x86 so I left it as is.

If you want me to move it, I'd be happy to do so.

In any case I think it would make sense to have some sort of written and
well-known policy about this, though.

> > Having the platform-driver-x86 on Cc would still be useful as they can provide
> > guidance about using the ACPI/WMI/platform APIs.
> > 
> 
> Sure, but that is unrelated to the driver location, and the opposite argument
> can be made as well (that drivers implementing subsystem code should be reviewed
> by subsystem maintainers). That is a much stronger argument in my opinion.
> 
> Guenter

Absolutely. I wanted to make two different points in my mail:

1) Maybe the driver should be moved into drivers/platform/x86 as the other
(single-use) WMI drivers are living there.
I don't know about any rule demanding that but was mentioning this so it stays
consistent.

2) The patch should *also* be reviewed by pdx86 as it is using their
infrastructure.
This was not meant to replace any of the hwmon involvement.

For example when I submitted gigabyte-wmi to pdx86 the maintainers they told
me to also solicit feedback from you as the hwmon maintainer.
And in the end both the hwmon parts (thank you!) and the wmi parts
(platform-device vs WMI bus, same as here) were much better than in the
first version.

> > For example by using the WMI bus as mentioned in my other mail would allow
> > to completely remove the manually maintained DMI list and instead directly bind
> > to the WMI GUID for any device that supports this GUID.
> > (This is possible as this WMI API seems to be self-describing, so all
> > specific parameters can be discovered by the driver)

Thomas

Re: [PATCH v3 2/2] hwmon: (asus_wmi_sensors) Support X370 Asus WMI.

[Guenter Roeck]

On 10/10/21 8:28 AM, Thomas Weißschuh wrote:
> On 2021-10-10T07:56-0700, Guenter Roeck wrote:
>> On 10/10/21 7:10 AM, Thomas Weißschuh wrote:
>>> On 2021-10-10T06:38-0700, Guenter Roeck wrote:
>>>> On 10/10/21 3:20 AM, Thomas Weißschuh wrote:
>>>>> Hi,
>>>>>
>>>>> for WMI drivers the list platform-driver-x86@vger.kernel.org should probably be
>>>>> on CC too.
>>>>> Also all other WMI drivers, even for hwmon stuff are located in
>>>>> drivers/platform/x86 so it may be better to put it there, too.
>>>>>
>>>>
>>>> Not really. If any of those other drivers are pure hwmon drivers, they
>>>> should reside in drivers/hwmon instead. And, yes, that really includes
>>>> the gigabyte-wmi driver. We don't have arbitrary drivers in drivers/pci
>>>> either just because they are drivers for pci devices.
>>>
>>> Fair enough.
>>> I suppose it would be too much churn to move gigabyte-wmi to
>>> hwmon now though, correct?
>>>
>>
>> Is it ? I don't recall the reason why it was added to drivers/platform/x86
>> in the first place. I see other single-use wmi drivers in that directory
>> as well (eg xiaomi-wmi, which should be in input). Is there some unwritten
>> rule stating that all wmi drivers shall reside in drivers/platform/x86,
>> no matter what subsystem they touch ?
> 
> There was no specific reason. I saw all the other WMI drivers in
> drivers/platform/x86 and added mine there and sent it to the recipients as
> reported by get_maintainer.pl.
> 

Sorry, that is not a valid reason or argument for me.

> You mentioned that it could move to hwmon but Hans said there are other
> single-use wmi drivers in drivers/platform/x86 so I left it as is.
> 
> If you want me to move it, I'd be happy to do so.
> 

At this point this is out of my control.

> In any case I think it would make sense to have some sort of written and
> well-known policy about this, though.
> 
Absolutely agree. Historically single-use drivers resided in subsystem directories,
and for multi-use drivers it was handled on a case-by-case basis. If that is being
changed (meaning subsystem driver control/maintenance/review is taken away from
subsystem maintainers), it should for sure be documented.

>>> Having the platform-driver-x86 on Cc would still be useful as they can provide
>>> guidance about using the ACPI/WMI/platform APIs.
>>>
>>
>> Sure, but that is unrelated to the driver location, and the opposite argument
>> can be made as well (that drivers implementing subsystem code should be reviewed
>> by subsystem maintainers). That is a much stronger argument in my opinion.
>>
>> Guenter
> 
> Absolutely. I wanted to make two different points in my mail:
> 
> 1) Maybe the driver should be moved into drivers/platform/x86 as the other
> (single-use) WMI drivers are living there.

Doing something wrong is neither a reason nor an argument to keep doing it.

> I don't know about any rule demanding that but was mentioning this so it stays
> consistent.
> 
> 2) The patch should *also* be reviewed by pdx86 as it is using their
> infrastructure.
> This was not meant to replace any of the hwmon involvement.
> 
> For example when I submitted gigabyte-wmi to pdx86 the maintainers they told
> me to also solicit feedback from you as the hwmon maintainer.
> And in the end both the hwmon parts (thank you!) and the wmi parts
> (platform-device vs WMI bus, same as here) were much better than in the
> first version.
> 

Sure. Unfortunately that is not always the case. Many drivers registering
with hwmon were never reviewed by a hwmon maintainer, and some of those make
me shiver when I look at them. Since v5.12, get_maintainer.pl lists hwmon
maintainers as reviewers if a driver makes a hwmon API call, so hopefully
that will help a bit.

Guenter

>>> For example by using the WMI bus as mentioned in my other mail would allow
>>> to completely remove the manually maintained DMI list and instead directly bind
>>> to the WMI GUID for any device that supports this GUID.
>>> (This is possible as this WMI API seems to be self-describing, so all
>>> specific parameters can be discovered by the driver)
> 
> Thomas
>