hwmon: (nct6775) Split core and platform driver

This splits the nct6775 driver into an interface-independent core and
a separate platform driver that wraps inb/outb port I/O (or asuswmi
methods) around that core.

Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Tested-by: Renze Nicolai <renze@rnplus.nl>
Link: https://lore.kernel.org/r/20220427010154.29749-7-zev@bewilderbeest.net
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

MAINTAINERS

@@ -13537,12 +13537,14 @@ M:	Samuel Mendoza-Jonas <sam@mendozajonas.com>
 S:	Maintained
 F:	net/ncsi/
 
-NCT6775 HARDWARE MONITOR DRIVER
+NCT6775 HARDWARE MONITOR DRIVER - CORE & PLATFORM DRIVER
 M:	Guenter Roeck <linux@roeck-us.net>
 L:	linux-hwmon@vger.kernel.org
 S:	Maintained
 F:	Documentation/hwmon/nct6775.rst
-F:	drivers/hwmon/nct6775.c
+F:	drivers/hwmon/nct6775-core.c
+F:	drivers/hwmon/nct6775-platform.c
+F:	drivers/hwmon/nct6775.h
 
 NETDEVSIM
 M:	Jakub Kicinski <kuba@kernel.org>

drivers/hwmon/Kconfig

@@ -1462,11 +1462,23 @@ config SENSORS_NCT6683
 	  This driver can also be built as a module. If so, the module
 	  will be called nct6683.
 
+config SENSORS_NCT6775_CORE
+	tristate
+	select REGMAP
+	help
+	  This module contains common code shared by the platform and
+	  i2c versions of the nct6775 driver; it is not useful on its
+	  own.
+
+	  If built as a module, the module will be called
+	  nct6775-core.
+
 config SENSORS_NCT6775
-	tristate "Nuvoton NCT6775F and compatibles"
+	tristate "Platform driver for Nuvoton NCT6775F and compatibles"
 	depends on !PPC
 	depends on ACPI_WMI || ACPI_WMI=n
 	select HWMON_VID
+	select SENSORS_NCT6775_CORE
 	help
 	  If you say yes here you get support for the hardware monitoring
 	  functionality of the Nuvoton NCT6106D, NCT6775F, NCT6776F, NCT6779D,

drivers/hwmon/Makefile

@@ -154,6 +154,8 @@ obj-$(CONFIG_SENSORS_MLXREG_FAN) += mlxreg-fan.o
 obj-$(CONFIG_SENSORS_MENF21BMC_HWMON) += menf21bmc_hwmon.o
 obj-$(CONFIG_SENSORS_MR75203)	+= mr75203.o
 obj-$(CONFIG_SENSORS_NCT6683)	+= nct6683.o
+obj-$(CONFIG_SENSORS_NCT6775_CORE) += nct6775-core.o
+nct6775-objs			:= nct6775-platform.o
 obj-$(CONFIG_SENSORS_NCT6775)	+= nct6775.o
 obj-$(CONFIG_SENSORS_NCT7802)	+= nct7802.o
 obj-$(CONFIG_SENSORS_NCT7904)	+= nct7904.o

drivers/hwmon/nct6775.h

@@ -0,0 +1,252 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef __HWMON_NCT6775_H__
+#define __HWMON_NCT6775_H__
+
+#include <linux/types.h>
+
+enum kinds { nct6106, nct6116, nct6775, nct6776, nct6779, nct6791, nct6792,
+	     nct6793, nct6795, nct6796, nct6797, nct6798 };
+enum pwm_enable { off, manual, thermal_cruise, speed_cruise, sf3, sf4 };
+
+#define NUM_TEMP	10	/* Max number of temp attribute sets w/ limits*/
+#define NUM_TEMP_FIXED	6	/* Max number of fixed temp attribute sets */
+#define NUM_TSI_TEMP	8	/* Max number of TSI temp register pairs */
+
+#define NUM_REG_ALARM	7	/* Max number of alarm registers */
+#define NUM_REG_BEEP	5	/* Max number of beep registers */
+
+#define NUM_FAN		7
+
+struct nct6775_data {
+	int addr;	/* IO base of hw monitor block */
+	int sioreg;	/* SIO register address */
+	enum kinds kind;
+	const char *name;
+
+	const struct attribute_group *groups[7];
+	u8 num_groups;
+
+	u16 reg_temp[5][NUM_TEMP]; /* 0=temp, 1=temp_over, 2=temp_hyst,
+				    * 3=temp_crit, 4=temp_lcrit
+				    */
+	u8 temp_src[NUM_TEMP];
+	u16 reg_temp_config[NUM_TEMP];
+	const char * const *temp_label;
+	u32 temp_mask;
+	u32 virt_temp_mask;
+
+	u16 REG_CONFIG;
+	u16 REG_VBAT;
+	u16 REG_DIODE;
+	u8 DIODE_MASK;
+
+	const s8 *ALARM_BITS;
+	const s8 *BEEP_BITS;
+
+	const u16 *REG_VIN;
+	const u16 *REG_IN_MINMAX[2];
+
+	const u16 *REG_TARGET;
+	const u16 *REG_FAN;
+	const u16 *REG_FAN_MODE;
+	const u16 *REG_FAN_MIN;
+	const u16 *REG_FAN_PULSES;
+	const u16 *FAN_PULSE_SHIFT;
+	const u16 *REG_FAN_TIME[3];
+
+	const u16 *REG_TOLERANCE_H;
+
+	const u8 *REG_PWM_MODE;
+	const u8 *PWM_MODE_MASK;
+
+	const u16 *REG_PWM[7];	/* [0]=pwm, [1]=pwm_start, [2]=pwm_floor,
+				 * [3]=pwm_max, [4]=pwm_step,
+				 * [5]=weight_duty_step, [6]=weight_duty_base
+				 */
+	const u16 *REG_PWM_READ;
+
+	const u16 *REG_CRITICAL_PWM_ENABLE;
+	u8 CRITICAL_PWM_ENABLE_MASK;
+	const u16 *REG_CRITICAL_PWM;
+
+	const u16 *REG_AUTO_TEMP;
+	const u16 *REG_AUTO_PWM;
+
+	const u16 *REG_CRITICAL_TEMP;
+	const u16 *REG_CRITICAL_TEMP_TOLERANCE;
+
+	const u16 *REG_TEMP_SOURCE;	/* temp register sources */
+	const u16 *REG_TEMP_SEL;
+	const u16 *REG_WEIGHT_TEMP_SEL;
+	const u16 *REG_WEIGHT_TEMP[3];	/* 0=base, 1=tolerance, 2=step */
+
+	const u16 *REG_TEMP_OFFSET;
+
+	const u16 *REG_ALARM;
+	const u16 *REG_BEEP;
+
+	const u16 *REG_TSI_TEMP;
+
+	unsigned int (*fan_from_reg)(u16 reg, unsigned int divreg);
+	unsigned int (*fan_from_reg_min)(u16 reg, unsigned int divreg);
+
+	struct mutex update_lock;
+	bool valid;		/* true if following fields are valid */
+	unsigned long last_updated;	/* In jiffies */
+
+	/* Register values */
+	u8 bank;		/* current register bank */
+	u8 in_num;		/* number of in inputs we have */
+	u8 in[15][3];		/* [0]=in, [1]=in_max, [2]=in_min */
+	unsigned int rpm[NUM_FAN];
+	u16 fan_min[NUM_FAN];
+	u8 fan_pulses[NUM_FAN];
+	u8 fan_div[NUM_FAN];
+	u8 has_pwm;
+	u8 has_fan;		/* some fan inputs can be disabled */
+	u8 has_fan_min;		/* some fans don't have min register */
+	bool has_fan_div;
+
+	u8 num_temp_alarms;	/* 2, 3, or 6 */
+	u8 num_temp_beeps;	/* 2, 3, or 6 */
+	u8 temp_fixed_num;	/* 3 or 6 */
+	u8 temp_type[NUM_TEMP_FIXED];
+	s8 temp_offset[NUM_TEMP_FIXED];
+	s16 temp[5][NUM_TEMP]; /* 0=temp, 1=temp_over, 2=temp_hyst,
+				* 3=temp_crit, 4=temp_lcrit
+				*/
+	s16 tsi_temp[NUM_TSI_TEMP];
+	u64 alarms;
+	u64 beeps;
+
+	u8 pwm_num;	/* number of pwm */
+	u8 pwm_mode[NUM_FAN];	/* 0->DC variable voltage,
+				 * 1->PWM variable duty cycle
+				 */
+	enum pwm_enable pwm_enable[NUM_FAN];
+			/* 0->off
+			 * 1->manual
+			 * 2->thermal cruise mode (also called SmartFan I)
+			 * 3->fan speed cruise mode
+			 * 4->SmartFan III
+			 * 5->enhanced variable thermal cruise (SmartFan IV)
+			 */
+	u8 pwm[7][NUM_FAN];	/* [0]=pwm, [1]=pwm_start, [2]=pwm_floor,
+				 * [3]=pwm_max, [4]=pwm_step,
+				 * [5]=weight_duty_step, [6]=weight_duty_base
+				 */
+
+	u8 target_temp[NUM_FAN];
+	u8 target_temp_mask;
+	u32 target_speed[NUM_FAN];
+	u32 target_speed_tolerance[NUM_FAN];
+	u8 speed_tolerance_limit;
+
+	u8 temp_tolerance[2][NUM_FAN];
+	u8 tolerance_mask;
+
+	u8 fan_time[3][NUM_FAN]; /* 0 = stop_time, 1 = step_up, 2 = step_down */
+
+	/* Automatic fan speed control registers */
+	int auto_pwm_num;
+	u8 auto_pwm[NUM_FAN][7];
+	u8 auto_temp[NUM_FAN][7];
+	u8 pwm_temp_sel[NUM_FAN];
+	u8 pwm_weight_temp_sel[NUM_FAN];
+	u8 weight_temp[3][NUM_FAN];	/* 0->temp_step, 1->temp_step_tol,
+					 * 2->temp_base
+					 */
+
+	u8 vid;
+	u8 vrm;
+
+	bool have_vid;
+
+	u16 have_temp;
+	u16 have_temp_fixed;
+	u16 have_tsi_temp;
+	u16 have_in;
+
+	/* Remember extra register values over suspend/resume */
+	u8 vbat;
+	u8 fandiv1;
+	u8 fandiv2;
+	u8 sio_reg_enable;
+
+	struct regmap *regmap;
+	bool read_only;
+
+	/* driver-specific (platform, i2c) initialization hook and data */
+	int (*driver_init)(struct nct6775_data *data);
+	void *driver_data;
+};
+
+static inline int nct6775_read_value(struct nct6775_data *data, u16 reg, u16 *value)
+{
+	unsigned int tmp;
+	int ret = regmap_read(data->regmap, reg, &tmp);
+
+	if (!ret)
+		*value = tmp;
+	return ret;
+}
+
+static inline int nct6775_write_value(struct nct6775_data *data, u16 reg, u16 value)
+{
+	return regmap_write(data->regmap, reg, value);
+}
+
+bool nct6775_reg_is_word_sized(struct nct6775_data *data, u16 reg);
+int nct6775_probe(struct device *dev, struct nct6775_data *data,
+		  const struct regmap_config *regmapcfg);
+
+ssize_t nct6775_show_alarm(struct device *dev, struct device_attribute *attr, char *buf);
+ssize_t nct6775_show_beep(struct device *dev, struct device_attribute *attr, char *buf);
+ssize_t nct6775_store_beep(struct device *dev, struct device_attribute *attr, const char *buf,
+			   size_t count);
+
+static inline int nct6775_write_temp(struct nct6775_data *data, u16 reg, u16 value)
+{
+	if (!nct6775_reg_is_word_sized(data, reg))
+		value >>= 8;
+	return nct6775_write_value(data, reg, value);
+}
+
+static inline umode_t nct6775_attr_mode(struct nct6775_data *data, struct attribute *attr)
+{
+	return data->read_only ? (attr->mode & ~0222) : attr->mode;
+}
+
+static inline int
+nct6775_add_attr_group(struct nct6775_data *data, const struct attribute_group *group)
+{
+	/* Need to leave a NULL terminator at the end of data->groups */
+	if (data->num_groups == ARRAY_SIZE(data->groups) - 1)
+		return -ENOBUFS;
+
+	data->groups[data->num_groups++] = group;
+	return 0;
+}
+
+#define NCT6775_REG_BANK	0x4E
+#define NCT6775_REG_CONFIG	0x40
+
+#define NCT6775_REG_FANDIV1		0x506
+#define NCT6775_REG_FANDIV2		0x507
+
+#define NCT6791_REG_HM_IO_SPACE_LOCK_ENABLE	0x28
+
+#define FAN_ALARM_BASE		16
+#define TEMP_ALARM_BASE		24
+#define INTRUSION_ALARM_BASE	30
+#define BEEP_ENABLE_BASE	15
+
+/*
+ * Not currently used:
+ * REG_MAN_ID has the value 0x5ca3 for all supported chips.
+ * REG_CHIP_ID == 0x88/0xa1/0xc1 depending on chip model.
+ * REG_MAN_ID is at port 0x4f
+ * REG_CHIP_ID is at port 0x58
+ */
+
+#endif /* __HWMON_NCT6775_H__ */