// 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 <linux/wmi.h>

#include "nct6775.h"

enum sensor_access { access_direct, access_asuswmi };

static const char * const nct6775_sio_names[] __initconst = {
	"NCT6106D",
	"NCT6116D",
	"NCT6775F",
	"NCT6776D/F",
	"NCT6779D",
	"NCT6791D",
	"NCT6792D",
	"NCT6793D",
	"NCT6795D",
	"NCT6796D",
	"NCT6797D",
	"NCT6798D",
};

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_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_MONITORING_GUID		"466747A0-70EC-11DE-8A39-0800200C9A66"
#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

static int nct6775_asuswmi_evaluate_method(u32 method_id, u8 bank, u8 reg, u8 val, u32 *retval)
{
#if IS_ENABLED(CONFIG_ACPI_WMI)
	u32 args = bank | (reg << 8) | (val << 16);
	struct acpi_buffer input = { (acpi_size) sizeof(args), &args };
	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
	acpi_status status;
	union acpi_object *obj;
	u32 tmp = ASUSWMI_UNSUPPORTED_METHOD;

	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_INTEGER)
		tmp = obj->integer.value;

	if (retval)
		*retval = tmp;

	kfree(obj);

	if (tmp == ASUSWMI_UNSUPPORTED_METHOD)
		return -ENODEV;
	return 0;
#else
	return -EOPNOTSUPP;
#endif
}

static inline int nct6775_asuswmi_write(u8 bank, u8 reg, u8 val)
{
	return nct6775_asuswmi_evaluate_method(ASUSWMI_METHODID_WHWM, bank,
					      reg, val, NULL);
}

static inline int nct6775_asuswmi_read(u8 bank, u8 reg, u8 *val)
{
	u32 ret, tmp = 0;

	ret = nct6775_asuswmi_evaluate_method(ASUSWMI_METHODID_RHWM, bank,
					      reg, 0, &tmp);
	*val = tmp;
	return ret;
}

static int superio_wmi_inb(struct nct6775_sio_data *sio_data, int reg)
{
	int tmp = 0;

	nct6775_asuswmi_evaluate_method(ASUSWMI_METHODID_RSIO, sio_data->ld,
					reg, 0, &tmp);
	return tmp;
}

static void superio_wmi_outb(struct nct6775_sio_data *sio_data, int reg, int val)
{
	nct6775_asuswmi_evaluate_method(ASUSWMI_METHODID_WSIO, sio_data->ld,
					reg, val, NULL);
}

static void superio_wmi_select(struct nct6775_sio_data *sio_data, int ld)
{
	sio_data->ld = ld;
}

static int superio_wmi_enter(struct nct6775_sio_data *sio_data)
{
	return 0;
}

static void superio_wmi_exit(struct nct6775_sio_data *sio_data)
{
}

static void superio_outb(struct nct6775_sio_data *sio_data, int reg, int val)
{
	int ioreg = sio_data->sioreg;

	outb(reg, ioreg);
	outb(val, ioreg + 1);
}

static int superio_inb(struct nct6775_sio_data *sio_data, int reg)
{
	int ioreg = sio_data->sioreg;

	outb(reg, ioreg);
	return inb(ioreg + 1);
}

static void superio_select(struct nct6775_sio_data *sio_data, int ld)
{
	int ioreg = sio_data->sioreg;

	outb(SIO_REG_LDSEL, ioreg);
	outb(ld, ioreg + 1);
}

static int superio_enter(struct nct6775_sio_data *sio_data)
{
	int ioreg = sio_data->sioreg;

	/*
	 * Try to reserve <ioreg> and <ioreg + 1> for exclusive access.
	 */
	if (!request_muxed_region(ioreg, 2, DRVNAME))
		return -EBUSY;

	outb(0x87, ioreg);
	outb(0x87, ioreg);

	return 0;
}

static void superio_exit(struct nct6775_sio_data *sio_data)
{
	int ioreg = sio_data->sioreg;

	outb(0xaa, ioreg);
	outb(0x02, ioreg);
	outb(0x02, ioreg + 1);
	release_region(ioreg, 2);
}

static inline void nct6775_wmi_set_bank(struct nct6775_data *data, u16 reg)
{
	u8 bank = reg >> 8;

	data->bank = bank;
}

static int nct6775_wmi_reg_read(void *ctx, unsigned int reg, unsigned int *val)
{
	struct nct6775_data *data = ctx;
	int err, word_sized = nct6775_reg_is_word_sized(data, reg);
	u8 tmp = 0;
	u16 res;

	nct6775_wmi_set_bank(data, reg);

	err = nct6775_asuswmi_read(data->bank, reg & 0xff, &tmp);
	if (err)
		return err;

	res = tmp;
	if (word_sized) {
		err = nct6775_asuswmi_read(data->bank, (reg & 0xff) + 1, &tmp);
		if (err)
			return err;

		res = (res << 8) + tmp;
	}
	*val = res;
	return 0;
}

static int nct6775_wmi_reg_write(void *ctx, unsigned int reg, unsigned int value)
{
	struct nct6775_data *data = ctx;
	int res, word_sized = nct6775_reg_is_word_sized(data, reg);

	nct6775_wmi_set_bank(data, reg);

	if (word_sized) {
		res = nct6775_asuswmi_write(data->bank, reg & 0xff, value >> 8);
		if (res)
			return res;

		res = nct6775_asuswmi_write(data->bank, (reg & 0xff) + 1, value);
	} else {
		res = nct6775_asuswmi_write(data->bank, reg & 0xff, value);
	}

	return res;
}

/*
 * On older chips, only registers 0x50-0x5f are banked.
 * On more recent chips, all registers are banked.
 * Assume that is the case and set the bank number for each access.
 * Cache the bank number so it only needs to be set if it changes.
 */
static inline void nct6775_set_bank(struct nct6775_data *data, u16 reg)
{
	u8 bank = reg >> 8;

	if (data->bank != bank) {
		outb_p(NCT6775_REG_BANK, data->addr + ADDR_REG_OFFSET);
		outb_p(bank, data->addr + DATA_REG_OFFSET);
		data->bank = bank;
	}
}

static int nct6775_reg_read(void *ctx, unsigned int reg, unsigned int *val)
{
	struct nct6775_data *data = ctx;
	int word_sized = nct6775_reg_is_word_sized(data, reg);

	nct6775_set_bank(data, reg);
	outb_p(reg & 0xff, data->addr + ADDR_REG_OFFSET);
	*val = inb_p(data->addr + DATA_REG_OFFSET);
	if (word_sized) {
		outb_p((reg & 0xff) + 1,
		       data->addr + ADDR_REG_OFFSET);
		*val = (*val << 8) + inb_p(data->addr + DATA_REG_OFFSET);
	}
	return 0;
}

static int nct6775_reg_write(void *ctx, unsigned int reg, unsigned int value)
{
	struct nct6775_data *data = ctx;
	int word_sized = nct6775_reg_is_word_sized(data, reg);

	nct6775_set_bank(data, reg);
	outb_p(reg & 0xff, data->addr + ADDR_REG_OFFSET);
	if (word_sized) {
		outb_p(value >> 8, data->addr + DATA_REG_OFFSET);
		outb_p((reg & 0xff) + 1,
		       data->addr + ADDR_REG_OFFSET);
	}
	outb_p(value & 0xff, data->addr + DATA_REG_OFFSET);
	return 0;
}

static void nct6791_enable_io_mapping(struct nct6775_sio_data *sio_data)
{
	int val;

	val = sio_data->sio_inb(sio_data, NCT6791_REG_HM_IO_SPACE_LOCK_ENABLE);
	if (val & 0x10) {
		pr_info("Enabling hardware monitor logical device mappings.\n");
		sio_data->sio_outb(sio_data, NCT6791_REG_HM_IO_SPACE_LOCK_ENABLE,
			       val & ~0x10);
	}
}

static int __maybe_unused nct6775_suspend(struct device *dev)
{
	int err;
	u16 tmp;
	struct nct6775_data *data = nct6775_update_device(dev);

	if (IS_ERR(data))
		return PTR_ERR(data);

	mutex_lock(&data->update_lock);
	err = nct6775_read_value(data, data->REG_VBAT, &tmp);
	if (err)
		goto out;
	data->vbat = tmp;
	if (data->kind == nct6775) {
		err = nct6775_read_value(data, NCT6775_REG_FANDIV1, &tmp);
		if (err)
			goto out;
		data->fandiv1 = tmp;

		err = nct6775_read_value(data, NCT6775_REG_FANDIV2, &tmp);
		if (err)
			goto out;
		data->fandiv2 = tmp;
	}
out:
	mutex_unlock(&data->update_lock);

	return err;
}

static int __maybe_unused nct6775_resume(struct device *dev)
{
	struct nct6775_data *data = dev_get_drvdata(dev);
	struct nct6775_sio_data *sio_data = dev_get_platdata(dev);
	int i, j, err = 0;
	u8 reg;

	mutex_lock(&data->update_lock);
	data->bank = 0xff;		/* Force initial bank selection */

	err = sio_data->sio_enter(sio_data);
	if (err)
		goto abort;

	sio_data->sio_select(sio_data, NCT6775_LD_HWM);
	reg = sio_data->sio_inb(sio_data, SIO_REG_ENABLE);
	if (reg != data->sio_reg_enable)
		sio_data->sio_outb(sio_data, SIO_REG_ENABLE, data->sio_reg_enable);

	if (data->kind == nct6791 || data->kind == nct6792 ||
	    data->kind == nct6793 || data->kind == nct6795 ||
	    data->kind == nct6796 || data->kind == nct6797 ||
	    data->kind == nct6798)
		nct6791_enable_io_mapping(sio_data);

	sio_data->sio_exit(sio_data);

	/* Restore limits */
	for (i = 0; i < data->in_num; i++) {
		if (!(data->have_in & BIT(i)))
			continue;

		err = nct6775_write_value(data, data->REG_IN_MINMAX[0][i], data->in[i][1]);
		if (err)
			goto abort;
		err = nct6775_write_value(data, data->REG_IN_MINMAX[1][i], data->in[i][2]);
		if (err)
			goto abort;
	}

	for (i = 0; i < ARRAY_SIZE(data->fan_min); i++) {
		if (!(data->has_fan_min & BIT(i)))
			continue;

		err = nct6775_write_value(data, data->REG_FAN_MIN[i], data->fan_min[i]);
		if (err)
			goto abort;
	}

	for (i = 0; i < NUM_TEMP; i++) {
		if (!(data->have_temp & BIT(i)))
			continue;

		for (j = 1; j < ARRAY_SIZE(data->reg_temp); j++)
			if (data->reg_temp[j][i]) {
				err = nct6775_write_temp(data, data->reg_temp[j][i],
							 data->temp[j][i]);
				if (err)
					goto abort;
			}
	}

	/* Restore other settings */
	err = nct6775_write_value(data, data->REG_VBAT, data->vbat);
	if (err)
		goto abort;
	if (data->kind == nct6775) {
		err = nct6775_write_value(data, NCT6775_REG_FANDIV1, data->fandiv1);
		if (err)
			goto abort;
		err = nct6775_write_value(data, NCT6775_REG_FANDIV2, data->fandiv2);
	}

abort:
	/* Force re-reading all values */
	data->valid = false;
	mutex_unlock(&data->update_lock);

	return err;
}

static SIMPLE_DEV_PM_OPS(nct6775_dev_pm_ops, nct6775_suspend, nct6775_resume);

static void
nct6775_check_fan_inputs(struct nct6775_data *data, struct nct6775_sio_data *sio_data)
{
	bool fan3pin = false, fan4pin = false, fan4min = false;
	bool fan5pin = false, fan6pin = false, fan7pin = false;
	bool pwm3pin = false, pwm4pin = false, pwm5pin = false;
	bool pwm6pin = false, pwm7pin = false;

	/* Store SIO_REG_ENABLE for use during resume */
	sio_data->sio_select(sio_data, NCT6775_LD_HWM);
	data->sio_reg_enable = sio_data->sio_inb(sio_data, SIO_REG_ENABLE);

	/* fan4 and fan5 share some pins with the GPIO and serial flash */
	if (data->kind == nct6775) {
		int cr2c = sio_data->sio_inb(sio_data, 0x2c);

		fan3pin = cr2c & BIT(6);
		pwm3pin = cr2c & BIT(7);

		/* On NCT6775, fan4 shares pins with the fdc interface */
		fan4pin = !(sio_data->sio_inb(sio_data, 0x2A) & 0x80);
	} else if (data->kind == nct6776) {
		bool gpok = sio_data->sio_inb(sio_data, 0x27) & 0x80;
		const char *board_vendor, *board_name;

		board_vendor = dmi_get_system_info(DMI_BOARD_VENDOR);
		board_name = dmi_get_system_info(DMI_BOARD_NAME);

		if (board_name && board_vendor &&
		    !strcmp(board_vendor, "ASRock")) {
			/*
			 * Auxiliary fan monitoring is not enabled on ASRock
			 * Z77 Pro4-M if booted in UEFI Ultra-FastBoot mode.
			 * Observed with BIOS version 2.00.
			 */
			if (!strcmp(board_name, "Z77 Pro4-M")) {
				if ((data->sio_reg_enable & 0xe0) != 0xe0) {
					data->sio_reg_enable |= 0xe0;
					sio_data->sio_outb(sio_data, SIO_REG_ENABLE,
						     data->sio_reg_enable);
				}
			}
		}

		if (data->sio_reg_enable & 0x80)
			fan3pin = gpok;
		else
			fan3pin = !(sio_data->sio_inb(sio_data, 0x24) & 0x40);

		if (data->sio_reg_enable & 0x40)
			fan4pin = gpok;
		else
			fan4pin = sio_data->sio_inb(sio_data, 0x1C) & 0x01;

		if (data->sio_reg_enable & 0x20)
			fan5pin = gpok;
		else
			fan5pin = sio_data->sio_inb(sio_data, 0x1C) & 0x02;

		fan4min = fan4pin;
		pwm3pin = fan3pin;
	} else if (data->kind == nct6106) {
		int cr24 = sio_data->sio_inb(sio_data, 0x24);

		fan3pin = !(cr24 & 0x80);
		pwm3pin = cr24 & 0x08;
	} else if (data->kind == nct6116) {
		int cr1a = sio_data->sio_inb(sio_data, 0x1a);
		int cr1b = sio_data->sio_inb(sio_data, 0x1b);
		int cr24 = sio_data->sio_inb(sio_data, 0x24);
		int cr2a = sio_data->sio_inb(sio_data, 0x2a);
		int cr2b = sio_data->sio_inb(sio_data, 0x2b);
		int cr2f = sio_data->sio_inb(sio_data, 0x2f);

		fan3pin = !(cr2b & 0x10);
		fan4pin = (cr2b & 0x80) ||			// pin 1(2)
			(!(cr2f & 0x10) && (cr1a & 0x04));	// pin 65(66)
		fan5pin = (cr2b & 0x80) ||			// pin 126(127)
			(!(cr1b & 0x03) && (cr2a & 0x02));	// pin 94(96)

		pwm3pin = fan3pin && (cr24 & 0x08);
		pwm4pin = fan4pin;
		pwm5pin = fan5pin;
	} else {
		/*
		 * NCT6779D, NCT6791D, NCT6792D, NCT6793D, NCT6795D, NCT6796D,
		 * NCT6797D, NCT6798D
		 */
		int cr1a = sio_data->sio_inb(sio_data, 0x1a);
		int cr1b = sio_data->sio_inb(sio_data, 0x1b);
		int cr1c = sio_data->sio_inb(sio_data, 0x1c);
		int cr1d = sio_data->sio_inb(sio_data, 0x1d);
		int cr2a = sio_data->sio_inb(sio_data, 0x2a);
		int cr2b = sio_data->sio_inb(sio_data, 0x2b);
		int cr2d = sio_data->sio_inb(sio_data, 0x2d);
		int cr2f = sio_data->sio_inb(sio_data, 0x2f);
		bool dsw_en = cr2f & BIT(3);
		bool ddr4_en = cr2f & BIT(4);
		int cre0;
		int creb;
		int cred;

		sio_data->sio_select(sio_data, NCT6775_LD_12);
		cre0 = sio_data->sio_inb(sio_data, 0xe0);
		creb = sio_data->sio_inb(sio_data, 0xeb);
		cred = sio_data->sio_inb(sio_data, 0xed);

		fan3pin = !(cr1c & BIT(5));
		fan4pin = !(cr1c & BIT(6));
		fan5pin = !(cr1c & BIT(7));

		pwm3pin = !(cr1c & BIT(0));
		pwm4pin = !(cr1c & BIT(1));
		pwm5pin = !(cr1c & BIT(2));

		switch (data->kind) {
		case nct6791:
			fan6pin = cr2d & BIT(1);
			pwm6pin = cr2d & BIT(0);
			break;
		case nct6792:
			fan6pin = !dsw_en && (cr2d & BIT(1));
			pwm6pin = !dsw_en && (cr2d & BIT(0));
			break;
		case nct6793:
			fan5pin |= cr1b & BIT(5);
			fan5pin |= creb & BIT(5);

			fan6pin = !dsw_en && (cr2d & BIT(1));
			fan6pin |= creb & BIT(3);

			pwm5pin |= cr2d & BIT(7);
			pwm5pin |= (creb & BIT(4)) && !(cr2a & BIT(0));

			pwm6pin = !dsw_en && (cr2d & BIT(0));
			pwm6pin |= creb & BIT(2);
			break;
		case nct6795:
			fan5pin |= cr1b & BIT(5);
			fan5pin |= creb & BIT(5);

			fan6pin = (cr2a & BIT(4)) &&
					(!dsw_en || (cred & BIT(4)));
			fan6pin |= creb & BIT(3);

			pwm5pin |= cr2d & BIT(7);
			pwm5pin |= (creb & BIT(4)) && !(cr2a & BIT(0));

			pwm6pin = (cr2a & BIT(3)) && (cred & BIT(2));
			pwm6pin |= creb & BIT(2);
			break;
		case nct6796:
			fan5pin |= cr1b & BIT(5);
			fan5pin |= (cre0 & BIT(3)) && !(cr1b & BIT(0));
			fan5pin |= creb & BIT(5);

			fan6pin = (cr2a & BIT(4)) &&
					(!dsw_en || (cred & BIT(4)));
			fan6pin |= creb & BIT(3);

			fan7pin = !(cr2b & BIT(2));

			pwm5pin |= cr2d & BIT(7);
			pwm5pin |= (cre0 & BIT(4)) && !(cr1b & BIT(0));
			pwm5pin |= (creb & BIT(4)) && !(cr2a & BIT(0));

			pwm6pin = (cr2a & BIT(3)) && (cred & BIT(2));
			pwm6pin |= creb & BIT(2);

			pwm7pin = !(cr1d & (BIT(2) | BIT(3)));
			break;
		case nct6797:
			fan5pin |= !ddr4_en && (cr1b & BIT(5));
			fan5pin |= creb & BIT(5);

			fan6pin = cr2a & BIT(4);
			fan6pin |= creb & BIT(3);

			fan7pin = cr1a & BIT(1);

			pwm5pin |= (creb & BIT(4)) && !(cr2a & BIT(0));
			pwm5pin |= !ddr4_en && (cr2d & BIT(7));

			pwm6pin = creb & BIT(2);
			pwm6pin |= cred & BIT(2);

			pwm7pin = cr1d & BIT(4);
			break;
		case nct6798:
			fan6pin = !(cr1b & BIT(0)) && (cre0 & BIT(3));
			fan6pin |= cr2a & BIT(4);
			fan6pin |= creb & BIT(5);

			fan7pin = cr1b & BIT(5);
			fan7pin |= !(cr2b & BIT(2));
			fan7pin |= creb & BIT(3);

			pwm6pin = !(cr1b & BIT(0)) && (cre0 & BIT(4));
			pwm6pin |= !(cred & BIT(2)) && (cr2a & BIT(3));
			pwm6pin |= (creb & BIT(4)) && !(cr2a & BIT(0));

			pwm7pin = !(cr1d & (BIT(2) | BIT(3)));
			pwm7pin |= cr2d & BIT(7);
			pwm7pin |= creb & BIT(2);
			break;
		default:	/* NCT6779D */
			break;
		}

		fan4min = fan4pin;
	}

	/* fan 1 and 2 (0x03) are always present */
	data->has_fan = 0x03 | (fan3pin << 2) | (fan4pin << 3) |
		(fan5pin << 4) | (fan6pin << 5) | (fan7pin << 6);
	data->has_fan_min = 0x03 | (fan3pin << 2) | (fan4min << 3) |
		(fan5pin << 4) | (fan6pin << 5) | (fan7pin << 6);
	data->has_pwm = 0x03 | (pwm3pin << 2) | (pwm4pin << 3) |
		(pwm5pin << 4) | (pwm6pin << 5) | (pwm7pin << 6);
}

static ssize_t
cpu0_vid_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct nct6775_data *data = dev_get_drvdata(dev);

	return sprintf(buf, "%d\n", vid_from_reg(data->vid, data->vrm));
}

static DEVICE_ATTR_RO(cpu0_vid);

/* Case open detection */

static const u8 NCT6775_REG_CR_CASEOPEN_CLR[] = { 0xe6, 0xee };
static const u8 NCT6775_CR_CASEOPEN_CLR_MASK[] = { 0x20, 0x01 };

static ssize_t
clear_caseopen(struct device *dev, struct device_attribute *attr,
	       const char *buf, size_t count)
{
	struct nct6775_data *data = dev_get_drvdata(dev);
	struct nct6775_sio_data *sio_data = data->driver_data;
	int nr = to_sensor_dev_attr(attr)->index - INTRUSION_ALARM_BASE;
	unsigned long val;
	u8 reg;
	int ret;

	if (kstrtoul(buf, 10, &val) || val != 0)
		return -EINVAL;

	mutex_lock(&data->update_lock);

	/*
	 * Use CR registers to clear caseopen status.
	 * The CR registers are the same for all chips, and not all chips
	 * support clearing the caseopen status through "regular" registers.
	 */
	ret = sio_data->sio_enter(sio_data);
	if (ret) {
		count = ret;
		goto error;
	}

	sio_data->sio_select(sio_data, NCT6775_LD_ACPI);
	reg = sio_data->sio_inb(sio_data, NCT6775_REG_CR_CASEOPEN_CLR[nr]);
	reg |= NCT6775_CR_CASEOPEN_CLR_MASK[nr];
	sio_data->sio_outb(sio_data, NCT6775_REG_CR_CASEOPEN_CLR[nr], reg);
	reg &= ~NCT6775_CR_CASEOPEN_CLR_MASK[nr];
	sio_data->sio_outb(sio_data, NCT6775_REG_CR_CASEOPEN_CLR[nr], reg);
	sio_data->sio_exit(sio_data);

	data->valid = false;	/* Force cache refresh */
error:
	mutex_unlock(&data->update_lock);
	return count;
}

static SENSOR_DEVICE_ATTR(intrusion0_alarm, 0644, nct6775_show_alarm,
			  clear_caseopen, INTRUSION_ALARM_BASE);
static SENSOR_DEVICE_ATTR(intrusion1_alarm, 0644, nct6775_show_alarm,
			  clear_caseopen, INTRUSION_ALARM_BASE + 1);
static SENSOR_DEVICE_ATTR(intrusion0_beep, 0644, nct6775_show_beep,
			  nct6775_store_beep, INTRUSION_ALARM_BASE);
static SENSOR_DEVICE_ATTR(intrusion1_beep, 0644, nct6775_show_beep,
			  nct6775_store_beep, INTRUSION_ALARM_BASE + 1);
static SENSOR_DEVICE_ATTR(beep_enable, 0644, nct6775_show_beep,
			  nct6775_store_beep, BEEP_ENABLE_BASE);

static umode_t nct6775_other_is_visible(struct kobject *kobj,
					struct attribute *attr, int index)
{
	struct device *dev = kobj_to_dev(kobj);
	struct nct6775_data *data = dev_get_drvdata(dev);

	if (index == 0 && !data->have_vid)
		return 0;

	if (index == 1 || index == 2) {
		if (data->ALARM_BITS[INTRUSION_ALARM_BASE + index - 1] < 0)
			return 0;
	}

	if (index == 3 || index == 4) {
		if (data->BEEP_BITS[INTRUSION_ALARM_BASE + index - 3] < 0)
			return 0;
	}

	return nct6775_attr_mode(data, attr);
}

/*
 * nct6775_other_is_visible uses the index into the following array
 * to determine if attributes should be created or not.
 * Any change in order or content must be matched.
 */
static struct attribute *nct6775_attributes_other[] = {
	&dev_attr_cpu0_vid.attr,				/* 0 */
	&sensor_dev_attr_intrusion0_alarm.dev_attr.attr,	/* 1 */
	&sensor_dev_attr_intrusion1_alarm.dev_attr.attr,	/* 2 */
	&sensor_dev_attr_intrusion0_beep.dev_attr.attr,		/* 3 */
	&sensor_dev_attr_intrusion1_beep.dev_attr.attr,		/* 4 */
	&sensor_dev_attr_beep_enable.dev_attr.attr,		/* 5 */

	NULL
};

static const struct attribute_group nct6775_group_other = {
	.attrs = nct6775_attributes_other,
	.is_visible = nct6775_other_is_visible,
};

static int nct6775_platform_probe_init(struct nct6775_data *data)
{
	int err;
	u8 cr2a;
	struct nct6775_sio_data *sio_data = data->driver_data;

	err = sio_data->sio_enter(sio_data);
	if (err)
		return err;

	cr2a = sio_data->sio_inb(sio_data, 0x2a);
	switch (data->kind) {
	case nct6775:
		data->have_vid = (cr2a & 0x40);
		break;
	case nct6776:
		data->have_vid = (cr2a & 0x60) == 0x40;
		break;
	case nct6106:
	case nct6116:
	case nct6779:
	case nct6791:
	case nct6792:
	case nct6793:
	case nct6795:
	case nct6796:
	case nct6797:
	case nct6798:
		break;
	}

	/*
	 * Read VID value
	 * We can get the VID input values directly at logical device D 0xe3.
	 */
	if (data->have_vid) {
		sio_data->sio_select(sio_data, NCT6775_LD_VID);
		data->vid = sio_data->sio_inb(sio_data, 0xe3);
		data->vrm = vid_which_vrm();
	}

	if (fan_debounce) {
		u8 tmp;

		sio_data->sio_select(sio_data, NCT6775_LD_HWM);
		tmp = sio_data->sio_inb(sio_data,
				    NCT6775_REG_CR_FAN_DEBOUNCE);
		switch (data->kind) {
		case nct6106:
		case nct6116:
			tmp |= 0xe0;
			break;
		case nct6775:
			tmp |= 0x1e;
			break;
		case nct6776:
		case nct6779:
			tmp |= 0x3e;
			break;
		case nct6791:
		case nct6792:
		case nct6793:
		case nct6795:
		case nct6796:
		case nct6797:
		case nct6798:
			tmp |= 0x7e;
			break;
		}
		sio_data->sio_outb(sio_data, NCT6775_REG_CR_FAN_DEBOUNCE,
			     tmp);
		pr_info("Enabled fan debounce for chip %s\n", data->name);
	}

	nct6775_check_fan_inputs(data, sio_data);

	sio_data->sio_exit(sio_data);

	return nct6775_add_attr_group(data, &nct6775_group_other);
}

static const struct regmap_config nct6775_regmap_config = {
	.reg_bits = 16,
	.val_bits = 16,
	.reg_read = nct6775_reg_read,
	.reg_write = nct6775_reg_write,
};

static const struct regmap_config nct6775_wmi_regmap_config = {
	.reg_bits = 16,
	.val_bits = 16,
	.reg_read = nct6775_wmi_reg_read,
	.reg_write = nct6775_wmi_reg_write,
};

static int nct6775_platform_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct nct6775_sio_data *sio_data = dev_get_platdata(dev);
	struct nct6775_data *data;
	struct resource *res;
	const struct regmap_config *regmapcfg;

	if (sio_data->access == access_direct) {
		res = platform_get_resource(pdev, IORESOURCE_IO, 0);
		if (!devm_request_region(&pdev->dev, res->start, IOREGION_LENGTH, DRVNAME))
			return -EBUSY;
	}

	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	data->kind = sio_data->kind;
	data->sioreg = sio_data->sioreg;

	if (sio_data->access == access_direct) {
		data->addr = res->start;
		regmapcfg = &nct6775_regmap_config;
	} else {
		regmapcfg = &nct6775_wmi_regmap_config;
	}

	platform_set_drvdata(pdev, data);

	data->driver_data = sio_data;
	data->driver_init = nct6775_platform_probe_init;

	return nct6775_probe(&pdev->dev, data, regmapcfg);
}

static struct platform_driver nct6775_driver = {
	.driver = {
		.name	= DRVNAME,
		.pm	= &nct6775_dev_pm_ops,
	},
	.probe		= nct6775_platform_probe,
};

/* nct6775_find() looks for a '627 in the Super-I/O config space */
static int __init nct6775_find(int sioaddr, struct nct6775_sio_data *sio_data)
{
	u16 val;
	int err;
	int addr;

	sio_data->access = access_direct;
	sio_data->sioreg = sioaddr;

	err = sio_data->sio_enter(sio_data);
	if (err)
		return err;

	val = (sio_data->sio_inb(sio_data, SIO_REG_DEVID) << 8) |
		sio_data->sio_inb(sio_data, SIO_REG_DEVID + 1);
	if (force_id && val != 0xffff)
		val = force_id;

	switch (val & SIO_ID_MASK) {
	case SIO_NCT6106_ID:
		sio_data->kind = nct6106;
		break;
	case SIO_NCT6116_ID:
		sio_data->kind = nct6116;
		break;
	case SIO_NCT6775_ID:
		sio_data->kind = nct6775;
		break;
	case SIO_NCT6776_ID:
		sio_data->kind = nct6776;
		break;
	case SIO_NCT6779_ID:
		sio_data->kind = nct6779;
		break;
	case SIO_NCT6791_ID:
		sio_data->kind = nct6791;
		break;
	case SIO_NCT6792_ID:
		sio_data->kind = nct6792;
		break;
	case SIO_NCT6793_ID:
		sio_data->kind = nct6793;
		break;
	case SIO_NCT6795_ID:
		sio_data->kind = nct6795;
		break;
	case SIO_NCT6796_ID:
		sio_data->kind = nct6796;
		break;
	case SIO_NCT6797_ID:
		sio_data->kind = nct6797;
		break;
	case SIO_NCT6798_ID:
		sio_data->kind = nct6798;
		break;
	default:
		if (val != 0xffff)
			pr_debug("unsupported chip ID: 0x%04x\n", val);
		sio_data->sio_exit(sio_data);
		return -ENODEV;
	}

	/* We have a known chip, find the HWM I/O address */
	sio_data->sio_select(sio_data, NCT6775_LD_HWM);
	val = (sio_data->sio_inb(sio_data, SIO_REG_ADDR) << 8)
	    | sio_data->sio_inb(sio_data, SIO_REG_ADDR + 1);
	addr = val & IOREGION_ALIGNMENT;
	if (addr == 0) {
		pr_err("Refusing to enable a Super-I/O device with a base I/O port 0\n");
		sio_data->sio_exit(sio_data);
		return -ENODEV;
	}

	/* Activate logical device if needed */
	val = sio_data->sio_inb(sio_data, SIO_REG_ENABLE);
	if (!(val & 0x01)) {
		pr_warn("Forcibly enabling Super-I/O. Sensor is probably unusable.\n");
		sio_data->sio_outb(sio_data, SIO_REG_ENABLE, val | 0x01);
	}

	if (sio_data->kind == nct6791 || sio_data->kind == nct6792 ||
	    sio_data->kind == nct6793 || sio_data->kind == nct6795 ||
	    sio_data->kind == nct6796 || sio_data->kind == nct6797 ||
	    sio_data->kind == nct6798)
		nct6791_enable_io_mapping(sio_data);

	sio_data->sio_exit(sio_data);
	pr_info("Found %s or compatible chip at %#x:%#x\n",
		nct6775_sio_names[sio_data->kind], sioaddr, addr);

	return addr;
}

/*
 * when Super-I/O functions move to a separate file, the Super-I/O
 * bus will manage the lifetime of the device and this module will only keep
 * track of the nct6775 driver. But since we use platform_device_alloc(), we
 * must keep track of the device
 */
static struct platform_device *pdev[2];

static const char * const asus_wmi_boards[] = {
	"PRO H410T",
	"ProArt X570-CREATOR WIFI",
	"Pro B550M-C",
	"Pro WS X570-ACE",
	"PRIME B360-PLUS",
	"PRIME B460-PLUS",
	"PRIME B550-PLUS",
	"PRIME B550M-A",
	"PRIME B550M-A (WI-FI)",
	"PRIME H410M-R",
	"PRIME X570-P",
	"PRIME X570-PRO",
	"ROG CROSSHAIR VIII DARK HERO",
	"ROG CROSSHAIR VIII FORMULA",
	"ROG CROSSHAIR VIII HERO",
	"ROG CROSSHAIR VIII IMPACT",
	"ROG STRIX B550-A GAMING",
	"ROG STRIX B550-E GAMING",
	"ROG STRIX B550-F GAMING",
	"ROG STRIX B550-F GAMING (WI-FI)",
	"ROG STRIX B550-F GAMING WIFI II",
	"ROG STRIX B550-I GAMING",
	"ROG STRIX B550-XE GAMING (WI-FI)",
	"ROG STRIX X570-E GAMING",
	"ROG STRIX X570-E GAMING WIFI II",
	"ROG STRIX X570-F GAMING",
	"ROG STRIX X570-I GAMING",
	"ROG STRIX Z390-E GAMING",
	"ROG STRIX Z390-F GAMING",
	"ROG STRIX Z390-H GAMING",
	"ROG STRIX Z390-I GAMING",
	"ROG STRIX Z490-A GAMING",
	"ROG STRIX Z490-E GAMING",
	"ROG STRIX Z490-F GAMING",
	"ROG STRIX Z490-G GAMING",
	"ROG STRIX Z490-G GAMING (WI-FI)",
	"ROG STRIX Z490-H GAMING",
	"ROG STRIX Z490-I GAMING",
	"TUF GAMING B550M-PLUS",
	"TUF GAMING B550M-PLUS (WI-FI)",
	"TUF GAMING B550-PLUS",
	"TUF GAMING B550-PRO",
	"TUF GAMING X570-PLUS",
	"TUF GAMING X570-PLUS (WI-FI)",
	"TUF GAMING X570-PRO (WI-FI)",
	"TUF GAMING Z490-PLUS",
	"TUF GAMING Z490-PLUS (WI-FI)",
};

static int __init sensors_nct6775_platform_init(void)
{
	int i, err;
	bool found = false;
	int address;
	struct resource res;
	struct nct6775_sio_data sio_data;
	int sioaddr[2] = { 0x2e, 0x4e };
	enum sensor_access access = access_direct;
	const char *board_vendor, *board_name;
	u8 tmp;

	err = platform_driver_register(&nct6775_driver);
	if (err)
		return err;

	board_vendor = dmi_get_system_info(DMI_BOARD_VENDOR);
	board_name = dmi_get_system_info(DMI_BOARD_NAME);

	if (board_name && board_vendor &&
	    !strcmp(board_vendor, "ASUSTeK COMPUTER INC.")) {
		err = match_string(asus_wmi_boards, ARRAY_SIZE(asus_wmi_boards),
				   board_name);
		if (err >= 0) {
			/* if reading chip id via WMI succeeds, use WMI */
			if (!nct6775_asuswmi_read(0, NCT6775_PORT_CHIPID, &tmp) && tmp) {
				pr_info("Using Asus WMI to access %#x chip.\n", tmp);
				access = access_asuswmi;
			} else {
				pr_err("Can't read ChipID by Asus WMI.\n");
			}
		}
	}

	/*
	 * initialize sio_data->kind and sio_data->sioreg.
	 *
	 * when Super-I/O functions move to a separate file, the Super-I/O
	 * driver will probe 0x2e and 0x4e and auto-detect the presence of a
	 * nct6775 hardware monitor, and call probe()
	 */
	for (i = 0; i < ARRAY_SIZE(pdev); i++) {
		sio_data.sio_outb = superio_outb;
		sio_data.sio_inb = superio_inb;
		sio_data.sio_select = superio_select;
		sio_data.sio_enter = superio_enter;
		sio_data.sio_exit = superio_exit;

		address = nct6775_find(sioaddr[i], &sio_data);
		if (address <= 0)
			continue;

		found = true;

		sio_data.access = access;

		if (access == access_asuswmi) {
			sio_data.sio_outb = superio_wmi_outb;
			sio_data.sio_inb = superio_wmi_inb;
			sio_data.sio_select = superio_wmi_select;
			sio_data.sio_enter = superio_wmi_enter;
			sio_data.sio_exit = superio_wmi_exit;
		}

		pdev[i] = platform_device_alloc(DRVNAME, address);
		if (!pdev[i]) {
			err = -ENOMEM;
			goto exit_device_unregister;
		}

		err = platform_device_add_data(pdev[i], &sio_data,
					       sizeof(struct nct6775_sio_data));
		if (err)
			goto exit_device_put;

		if (sio_data.access == access_direct) {
			memset(&res, 0, sizeof(res));
			res.name = DRVNAME;
			res.start = address + IOREGION_OFFSET;
			res.end = address + IOREGION_OFFSET + IOREGION_LENGTH - 1;
			res.flags = IORESOURCE_IO;

			err = acpi_check_resource_conflict(&res);
			if (err) {
				platform_device_put(pdev[i]);
				pdev[i] = NULL;
				continue;
			}

			err = platform_device_add_resources(pdev[i], &res, 1);
			if (err)
				goto exit_device_put;
		}

		/* platform_device_add calls probe() */
		err = platform_device_add(pdev[i]);
		if (err)
			goto exit_device_put;
	}
	if (!found) {
		err = -ENODEV;
		goto exit_unregister;
	}

	return 0;

exit_device_put:
	platform_device_put(pdev[i]);
exit_device_unregister:
	while (--i >= 0) {
		if (pdev[i])
			platform_device_unregister(pdev[i]);
	}
exit_unregister:
	platform_driver_unregister(&nct6775_driver);
	return err;
}

static void __exit sensors_nct6775_platform_exit(void)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(pdev); i++) {
		if (pdev[i])
			platform_device_unregister(pdev[i]);
	}
	platform_driver_unregister(&nct6775_driver);
}

MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
MODULE_DESCRIPTION("Platform driver for NCT6775F and compatible chips");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS(HWMON_NCT6775);

module_init(sensors_nct6775_platform_init);
module_exit(sensors_nct6775_platform_exit);