[PATCH v2 3/7] hwmon: (nct6683) Enable fan control on ASRock B850 Steel Legend WiFi

[Johan Dahlin <jdahlin@gmail.com>]

The NCT6686D on the ASRock B850 Steel Legend WiFi (customer ID 0x164a)
uses the same fan mode register and configuration phase as the NCT6687D-R
on MSI boards.

Enable fan control for channels 0 to 7 on this board.

Tested with pwm6_enable set to 1: pwm6 written as 255, 120 and 60 gives
803, 577 and 342 RPM on fan6. Writing 2 returns the fan to the BIOS
curve, and so does unloading the driver.

Signed-off-by: Johan Dahlin <jdahlin@gmail.com>
---
 Documentation/hwmon/nct6683.rst | 4 ++++
 drivers/hwmon/nct6683.c         | 3 +++
 2 files changed, 7 insertions(+)

diff --git a/Documentation/hwmon/nct6683.rst b/Documentation/hwmon/nct6683.rst
index 4c137eda6583..026515c35243 100644
--- a/Documentation/hwmon/nct6683.rst
+++ b/Documentation/hwmon/nct6683.rst
@@ -57,6 +57,10 @@ Fan control is supported on MSI boards with an NCT6687D-R (customer ID
 pwm16 control the system fan headers that are present. pwmN controls the
 fan reported by fanN_input.
 
+It is also supported on the ASRock B850 Steel Legend WiFi (NCT6686D,
+customer ID 0x164a), where pwm1 to pwm6 control the fan headers reported
+by fan1 to fan6.
+
 pwmN_enable selects the fan control mode:
 
   * 1: manual mode, the duty cycle is set with pwmN
diff --git a/drivers/hwmon/nct6683.c b/drivers/hwmon/nct6683.c
index d43dcf90048b..29fbf438c04c 100644
--- a/drivers/hwmon/nct6683.c
+++ b/drivers/hwmon/nct6683.c
@@ -1539,6 +1539,9 @@ nct6683_setup_fans(struct nct6683_data *data)
 				data->have_curve |= BIT(i);
 		}
 	}
+
+	if (data->customer_id == NCT6683_CUSTOMER_ID_ASROCK8)
+		data->have_fan_ctrl = data->have_pwm & GENMASK(7, 0);
 }
 
 /*
-- 
2.53.0