hwmon: (it87) Add support for IT8689E

Add support for the ITE IT8689E Super I/O chip. The IT8689E supports
newer autopwm, 12mV ADC, 16-bit fans, six fans, six PWM channels,
PWM frequency 2, six temperature inputs, AVCC3, temperature offset,
and fan on/off control.

Give it8689 its own GPIO configuration block in it87_find() rather
than sharing the it8620/it8628 block. The shared block reads
IT87_SIO_PINX2_REG and either marks IN3 as internal AVCC or skips
IN9. Because it8689 declares FEAT_AVCC3, IN9 is already marked as
always-internal before the GPIO block is reached; applying the PINX2
check would either create duplicate AVCC labels on IN3 and IN9 or
incorrectly skip IN9.

Also update Documentation/hwmon/it87.rst and drivers/hwmon/Kconfig to
document the newly supported chip.

Signed-off-by: Markus Hoffmann <markus@thehoffs.at>
Link: https://lore.kernel.org/r/20260322103301.18112-1-markus@thehoffs.at
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

3 files changed, 82 insertions, 9 deletions

diff --git a/Documentation/hwmon/it87.rst b/Documentation/hwmon/it87.rst
index 5cef4f265000..fc1c90b023ae 100644
--- a/Documentation/hwmon/it87.rst
+++ b/Documentation/hwmon/it87.rst
@@ -25,6 +25,14 @@ Supported chips:
 
     Datasheet: Not publicly available
 
+  * IT8689E
+
+    Prefix: 'it8689'
+
+    Addresses scanned: from Super I/O config space (8 I/O ports)
+
+    Datasheet: Not publicly available
+
   * IT8705F
 
     Prefix: 'it87'
@@ -228,9 +236,9 @@ Description
 -----------
 
 This driver implements support for the IT8603E, IT8620E, IT8623E, IT8628E,
-IT8705F, IT8712F, IT8716F, IT8718F, IT8720F, IT8721F, IT8726F, IT8728F, IT8732F,
-IT8758E, IT8771E, IT8772E, IT8781F, IT8782F, IT8783E/F, IT8786E, IT8790E,
-IT8792E/IT8795E, IT87952E and SiS950 chips.
+IT8689E, IT8705F, IT8712F, IT8716F, IT8718F, IT8720F, IT8721F, IT8726F,
+IT8728F, IT8732F, IT8758E, IT8771E, IT8772E, IT8781F, IT8782F, IT8783E/F,
+IT8786E, IT8790E, IT8792E/IT8795E, IT87952E and SiS950 chips.
 
 These chips are 'Super I/O chips', supporting floppy disks, infrared ports,
 joysticks and other miscellaneous stuff. For hardware monitoring, they
@@ -274,6 +282,9 @@ of the fan is not supported (value 0 of pwmX_enable).
 The IT8620E and IT8628E are custom designs, hardware monitoring part is similar
 to IT8728F. It only supports 16-bit fan mode. Both chips support up to 6 fans.
 
+The IT8689E supports newer autopwm, 12mV ADC, 16-bit fans, six fans, six PWM
+channels, PWM frequency 2, six temperature inputs, and AVCC3 (in9).
+
 The IT8790E, IT8792E/IT8795E and IT87952E support up to 3 fans. 16-bit fan
 mode is always enabled.
 
@@ -301,12 +312,15 @@ of 0.016 volt.  IT8603E, IT8721F/IT8758E and IT8728F can measure between 0 and
 2.8 volts with a resolution of 0.0109 volt.  The battery voltage in8 does not
 have limit registers.
 
-On the IT8603E, IT8620E, IT8628E, IT8721F/IT8758E, IT8732F, IT8781F, IT8782F,
-and IT8783E/F, some voltage inputs are internal and scaled inside the chip:
+On the IT8603E, IT8620E, IT8628E, IT8689E, IT8721F/IT8758E, IT8732F, IT8781F,
+IT8782F, and IT8783E/F, some voltage inputs are internal and scaled inside the
+chip:
+
 * in3 (optional)
 * in7 (optional for IT8781F, IT8782F, and IT8783E/F)
 * in8 (always)
-* in9 (relevant for IT8603E only)
+* in9 (IT8603E, IT8622E, and IT8689E: always AVCC3; others: optional)
+
 The driver handles this transparently so user-space doesn't have to care.
 
 The VID lines (IT8712F/IT8716F/IT8718F/IT8720F) encode the core voltage value:
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 8af80e17d25e..9d49cfd4ef3d 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -909,8 +909,8 @@ config SENSORS_IT87
 	  If you say yes here you get support for ITE IT8705F, IT8712F, IT8716F,
 	  IT8718F, IT8720F, IT8721F, IT8726F, IT8728F, IT8732F, IT8758E,
 	  IT8771E, IT8772E, IT8781F, IT8782F, IT8783E/F, IT8786E, IT8790E,
-	  IT8603E, IT8620E, IT8623E, and IT8628E sensor chips, and the SiS950
-	  clone.
+	  IT8603E, IT8620E, IT8623E, IT8628E, and IT8689E sensor chips, and
+	  the SiS950 clone.
 
 	  This driver can also be built as a module. If so, the module
 	  will be called it87.
diff --git a/drivers/hwmon/it87.c b/drivers/hwmon/it87.c
index 5cfb98a0512f..5fd310662ee4 100644
--- a/drivers/hwmon/it87.c
+++ b/drivers/hwmon/it87.c
@@ -16,6 +16,7 @@
  *            IT8622E  Super I/O chip w/LPC interface
  *            IT8623E  Super I/O chip w/LPC interface
  *            IT8628E  Super I/O chip w/LPC interface
+ *            IT8689E  Super I/O chip w/LPC interface
  *            IT8705F  Super I/O chip w/LPC interface
  *            IT8712F  Super I/O chip w/LPC interface
  *            IT8716F  Super I/O chip w/LPC interface
@@ -64,7 +65,7 @@
 
 enum chips { it87, it8712, it8716, it8718, it8720, it8721, it8728, it8732,
 	     it8771, it8772, it8781, it8782, it8783, it8786, it8790,
-	     it8792, it8603, it8620, it8622, it8628, it87952 };
+	     it8792, it8603, it8620, it8622, it8628, it8689, it87952 };
 
 static struct platform_device *it87_pdev[2];
 
@@ -162,6 +163,7 @@ static inline void superio_exit(int ioreg, bool noexit)
 #define IT8622E_DEVID 0x8622
 #define IT8623E_DEVID 0x8623
 #define IT8628E_DEVID 0x8628
+#define IT8689E_DEVID 0x8689
 #define IT87952E_DEVID 0x8695
 
 /* Logical device 4 (Environmental Monitor) registers */
@@ -502,6 +504,15 @@ static const struct it87_devices it87_devices[] = {
 		  | FEAT_SIX_TEMP | FEAT_VIN3_5V | FEAT_FANCTL_ONOFF,
 		.peci_mask = 0x07,
 	},
+	[it8689] = {
+		.name = "it8689",
+		.model = "IT8689E",
+		.features = FEAT_NEWER_AUTOPWM | FEAT_12MV_ADC | FEAT_16BIT_FANS
+		  | FEAT_TEMP_OFFSET | FEAT_SIX_FANS | FEAT_IN7_INTERNAL
+		  | FEAT_SIX_PWM | FEAT_PWM_FREQ2 | FEAT_SIX_TEMP | FEAT_AVCC3
+		  | FEAT_FANCTL_ONOFF,
+		.smbus_bitmap = BIT(1) | BIT(2),
+	},
 	[it87952] = {
 		.name = "it87952",
 		.model = "IT87952E",
@@ -2785,6 +2796,9 @@ static int __init it87_find(int sioaddr, unsigned short *address,
 	case IT8628E_DEVID:
 		sio_data->type = it8628;
 		break;
+	case IT8689E_DEVID:
+		sio_data->type = it8689;
+		break;
 	case IT87952E_DEVID:
 		sio_data->type = it87952;
 		break;
@@ -3002,6 +3016,51 @@ static int __init it87_find(int sioaddr, unsigned short *address,
 
 		sio_data->beep_pin = superio_inb(sioaddr,
 						 IT87_SIO_BEEP_PIN_REG) & 0x3f;
+	} else if (sio_data->type == it8689) {
+		int reg;
+
+		superio_select(sioaddr, GPIO);
+
+		/* Check for pwm5 */
+		reg = superio_inb(sioaddr, IT87_SIO_GPIO1_REG);
+		if (reg & BIT(6))
+			sio_data->skip_pwm |= BIT(4);
+
+		/* Check for fan4, fan5 */
+		reg = superio_inb(sioaddr, IT87_SIO_GPIO2_REG);
+		if (!(reg & BIT(5)))
+			sio_data->skip_fan |= BIT(3);
+		if (!(reg & BIT(4)))
+			sio_data->skip_fan |= BIT(4);
+
+		/* Check for pwm3, fan3 */
+		reg = superio_inb(sioaddr, IT87_SIO_GPIO3_REG);
+		if (reg & BIT(6))
+			sio_data->skip_pwm |= BIT(2);
+		if (reg & BIT(7))
+			sio_data->skip_fan |= BIT(2);
+
+		/* Check for pwm4 */
+		reg = superio_inb(sioaddr, IT87_SIO_GPIO4_REG);
+		if (reg & BIT(2))
+			sio_data->skip_pwm |= BIT(3);
+
+		/* Check for pwm2, fan2 */
+		reg = superio_inb(sioaddr, IT87_SIO_GPIO5_REG);
+		if (reg & BIT(1))
+			sio_data->skip_pwm |= BIT(1);
+		if (reg & BIT(2))
+			sio_data->skip_fan |= BIT(1);
+		/* Check for pwm6, fan6 */
+		if (!(reg & BIT(7))) {
+			sio_data->skip_pwm |= BIT(5);
+			sio_data->skip_fan |= BIT(5);
+		}
+
+		/* in9 (AVCC3) is always internal, no PINX2 check needed */
+
+		sio_data->beep_pin = superio_inb(sioaddr,
+						 IT87_SIO_BEEP_PIN_REG) & 0x3f;
 	} else if (sio_data->type == it8622) {
 		int reg;