Commit e5c85221 authored by Guenter Roeck's avatar Guenter Roeck
Browse files

hwmon: (nct6775) Improve fan detection 



Recent chips support multiple pins for fan speed inputs and fan control
outputs. Examine all of them to determine supported fan controls.

Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent cc66b303

drivers/hwmon/nct6775.c

+37 −8
Original line number Diff line number Diff line
@@ -105,6 +105,7 @@ MODULE_PARM_DESC(fan_debounce, "Enable debouncing for fan RPM signal"); 
#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) */
@@ -3392,6 +3393,8 @@ nct6775_check_fan_inputs(struct nct6775_data *data) 
		pwm5pin = false;

		pwm6pin = false;

	} else {	/* NCT6779D, NCT6791D, NCT6792D, or NCT6793D */

		int regval_1b, regval_2a, regval_eb;



		regval = superio_inb(sioreg, 0x1c);



		fan3pin = !(regval & BIT(5));
@@ -3402,17 +3405,43 @@ nct6775_check_fan_inputs(struct nct6775_data *data) 
		pwm4pin = !(regval & BIT(1));

		pwm5pin = !(regval & BIT(2));



		fan4min = fan4pin;



		if (data->kind == nct6791 || data->kind == nct6792 ||

		    data->kind == nct6793) {

		regval = superio_inb(sioreg, 0x2d);

			fan6pin = (regval & BIT(1));

			pwm6pin = (regval & BIT(0));

		} else {	/* NCT6779D */

		switch (data->kind) {

		case nct6791:

		case nct6792:

			fan6pin = regval & BIT(1);

			pwm6pin = regval & BIT(0);

			break;

		case nct6793:

			regval_1b = superio_inb(sioreg, 0x1b);

			regval_2a = superio_inb(sioreg, 0x2a);



			if (!pwm5pin)

				pwm5pin = regval & BIT(7);

			fan6pin = regval & BIT(1);

			pwm6pin = regval & BIT(0);

			if (!fan5pin)

				fan5pin = regval_1b & BIT(5);



			superio_select(sioreg, NCT6775_LD_12);

			regval_eb = superio_inb(sioreg, 0xeb);

			if (!fan5pin)

				fan5pin = regval_eb & BIT(5);

			if (!pwm5pin)

				pwm5pin = (regval_eb & BIT(4)) &&

					   !(regval_2a & BIT(0));

			if (!fan6pin)

				fan6pin = regval_eb & BIT(3);

			if (!pwm6pin)

				pwm6pin = regval_eb & BIT(2);

			break;

		default:	/* NCT6779D */

			fan6pin = false;

			pwm6pin = false;

			break;

		}



		fan4min = fan4pin;

	}



	/* fan 1 and 2 (0x03) are always present */