path: root/drivers/hwmon/nct6775-platform.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * nct6775 - Platform driver for the hardware monitoring
 *	     functionality of Nuvoton NCT677x Super-I/O chips
 *
 * Copyright (C) 2012  Guenter Roeck <linux@roeck-us.net>
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/acpi.h>
#include <linux/dmi.h>
#include <linux/hwmon-sysfs.h>
#include <linux/hwmon-vid.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>

#include "nct6775.h"

enum sensor_access { access_direct, access_asuswmi };

static const char * const nct6775_sio_names[] __initconst = {
	[nct6106] = "NCT6106D",
	[nct6116] = "NCT6116D",
	[nct6775] = "NCT6775F",
	[nct6776] = "NCT6776D/F",
	[nct6779] = "NCT6779D",
	[nct6791] = "NCT6791D",
	[nct6792] = "NCT6792D",
	[nct6793] = "NCT6793D",
	[nct6795] = "NCT6795D",
	[nct6796] = "NCT6796D",
	[nct6797] = "NCT6797D",
	[nct6798] = "NCT6798D",
	[nct6799] = "NCT6796D-S/NCT6799D-R",
};

static unsigned short force_id;
module_param(force_id, ushort, 0);
MODULE_PARM_DESC(force_id, "Override the detected device ID");

static unsigned short fan_debounce;
module_param(fan_debounce, ushort, 0);
MODULE_PARM_DESC(fan_debounce, "Enable debouncing for fan RPM signal");

#define DRVNAME "nct6775"

#define NCT6775_PORT_CHIPID	0x58

/*
 * ISA constants
 */

#define IOREGION_ALIGNMENT	(~7)
#define IOREGION_OFFSET		5
#define IOREGION_LENGTH		2
#define ADDR_REG_OFFSET		0
#define DATA_REG_OFFSET		1

/*
 * Super-I/O constants and functions
 */

#define NCT6775_LD_ACPI		0x0a
#define NCT6775_LD_HWM		0x0b
#define NCT6775_LD_VID		0x0d
#define NCT6775_LD_12		0x12

#define SIO_REG_LDSEL		0x07	/* Logical device select */
#define SIO_REG_DEVID		0x20	/* Device ID (2 bytes) */
#define SIO_REG_ENABLE		0x30	/* Logical device enable */
#define SIO_REG_ADDR		0x60	/* Logical device address (2 bytes) */

#define SIO_NCT6106_ID		0xc450
#define SIO_NCT6116_ID		0xd280
#define SIO_NCT6775_ID		0xb470
#define SIO_NCT6776_ID		0xc330
#define SIO_NCT6779_ID		0xc560
#define SIO_NCT6791_ID		0xc800
#define SIO_NCT6792_ID		0xc910
#define SIO_NCT6793_ID		0xd120
#define SIO_NCT6795_ID		0xd350
#define SIO_NCT6796_ID		0xd420
#define SIO_NCT6797_ID		0xd450
#define SIO_NCT6798_ID		0xd428
#define SIO_NCT6799_ID		0xd800
#define SIO_ID_MASK		0xFFF8

/*
 * Control registers
 */
#define NCT6775_REG_CR_FAN_DEBOUNCE	0xf0

struct nct6775_sio_data {
	int sioreg;
	int ld;
	enum kinds kind;
	enum sensor_access access;

	/* superio_() callbacks  */
	void (*sio_outb)(struct nct6775_sio_data *sio_data, int reg, int val);
	int (*sio_inb)(struct nct6775_sio_data *sio_data, int reg);
	void (*sio_select)(struct nct6775_sio_data *sio_data, int ld);
	int (*sio_enter)(struct nct6775_sio_data *sio_data);
	void (*sio_exit)(struct nct6775_sio_data *sio_data);
};

#define ASUSWMI_METHOD			"WMBD"
#define ASUSWMI_METHODID_RSIO		0x5253494F
#define ASUSWMI_METHODID_WSIO		0x5753494F
#define ASUSWMI_METHODID_RHWM		0x5248574D
#define ASUSWMI_METHODID_WHWM		0x5748574D
#define ASUSWMI_UNSUPPORTED_METHOD	0xFFFFFFFE
#define ASUSWMI_DEVICE_HID		"PNP0C14"
#define ASUSWMI_DEVICE_UID		"ASUSWMI"
#define ASUSMSI_DEVICE_UID		"AsusMbSwInterface"

#if IS_ENABLED(CONFIG_ACPI)
/*
 * ASUS boards have only one device with WMI "WMBD" method and have provided
 * access to only one SuperIO chip at 0x0290.
 */
static struct acpi_device *asus_acpi_dev;
#endif

static int nct6775_asuswmi_evaluate_method(u32 method_id, u8 bank, u8 reg, u8 val, u32 *retval)
{
#if IS_ENABLED(CONFIG_ACPI)
	acpi_handle handle = acpi_device_handle(asus_acpi_dev);
	u32 args = bank | (reg << 8) | (val << 16);
	struct acpi_object_list input;
	union acpi_object params[3];
	unsigned long long result;
	acpi_status status;

	params[0].type = ACPI_TYPE_INTEGER;
	params[0].integer.value = 0;
	params[1].type = ACPI_TYPE_INTEGER;
	params[1].integer.value = method_id;
	params[2].type = ACPI_TYPE_BUFFER;
	params[2].buffer.length = sizeof(args);
	params[2].buffer.pointer = (void *)&args;
	input.count = 3;
	input.pointer = params;

	status = acpi_evaluate_integer(handle, ASUSWMI_METHOD, &input, &result);
	if (ACPI_FAILURE(status))
		retur