diff mbox series

[v4] platform/x86: thinkpad_acpi: Add Thinkpad Edge E531 fan support

Message ID 20240816141228.134529-1-kontakt@matthias-fetzer.de (mailing list archive)
State Accepted, archived
Headers show
Series [v4] platform/x86: thinkpad_acpi: Add Thinkpad Edge E531 fan support | expand

Commit Message

Matthias Fetzer Aug. 16, 2024, 2:12 p.m. UTC 
Fan control on the E531 is done using the ACPI methods FANG and
FANW. The correct parameters and register values were found by
analyzing EC firmware as well as DSDT. This has been tested on
my Thinkpad Edge E531 (6885CTO, BIOS HEET52WW 1.33).

Signed-off-by: Matthias Fetzer <kontakt@matthias-fetzer.de>
---

Changes in v4:
    - Remove unnecessary variable
Changes in v3:
    - Add missing newline
    - Remove redundant code
Changes in v2:
    - Fix typo in EC memory description
    - Split plausibilty check for better readability

 drivers/platform/x86/thinkpad_acpi.c | 143 ++++++++++++++++++++++++++-
 1 file changed, 142 insertions(+), 1 deletion(-)

Comments

Hans de Goede Aug. 19, 2024, 2:33 p.m. UTC | #1 
Hi,

On 8/16/24 4:12 PM, Matthias Fetzer wrote:
> Fan control on the E531 is done using the ACPI methods FANG and
> FANW. The correct parameters and register values were found by
> analyzing EC firmware as well as DSDT. This has been tested on
> my Thinkpad Edge E531 (6885CTO, BIOS HEET52WW 1.33).
> 
> Signed-off-by: Matthias Fetzer <kontakt@matthias-fetzer.de>

Thank you for your patch, I've applied this patch to my review-hans 
branch:
https://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86.git/log/?h=review-hans

Note it will show up in my review-hans branch once I've pushed my
local branch there, which might take a while.

Once I've run some tests on this branch the patches there will be
added to the platform-drivers-x86/for-next branch and eventually
will be included in the pdx86 pull-request to Linus for the next
merge-window.

Regards,

Hans



> ---
> 
> Changes in v4:
>     - Remove unnecessary variable
> Changes in v3:
>     - Add missing newline
>     - Remove redundant code
> Changes in v2:
>     - Fix typo in EC memory description
>     - Split plausibilty check for better readability
> 
>  drivers/platform/x86/thinkpad_acpi.c | 143 ++++++++++++++++++++++++++-
>  1 file changed, 142 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
> index 397b409064c9..96c58bc59018 100644
> --- a/drivers/platform/x86/thinkpad_acpi.c
> +++ b/drivers/platform/x86/thinkpad_acpi.c
> @@ -7751,6 +7751,28 @@ static struct ibm_struct volume_driver_data = {
>   * 	EC 0x2f (HFSP) might be available *for reading*, but do not use
>   * 	it for writing.
>   *
> + * TPACPI_FAN_RD_ACPI_FANG:
> + * 	ACPI FANG method: returns fan control register
> + *
> + *	Takes one parameter which is 0x8100 plus the offset to EC memory
> + *	address 0xf500 and returns the byte at this address.
> + *
> + *	0xf500:
> + *		When the value is less than 9 automatic mode is enabled
> + *	0xf502:
> + *		Contains the current fan speed from 0-100%
> + *	0xf506:
> + *		Bit 7 has to be set in order to enable manual control by
> + *		writing a value >= 9 to 0xf500
> + *
> + * TPACPI_FAN_WR_ACPI_FANW:
> + * 	ACPI FANG method: sets fan control registers
> + *
> + * 	Takes 0x8100 plus the offset to EC memory address 0xf500 and the
> + * 	value to be written there as parameters.
> + *
> + *	see TPACPI_FAN_RD_ACPI_FANG
> + *
>   * TPACPI_FAN_WR_TPEC:
>   * 	ThinkPad EC register 0x2f (HFSP): fan control loop mode
>   * 	Supported on almost all ThinkPads
> @@ -7884,6 +7906,7 @@ enum {					/* Fan control constants */
>  enum fan_status_access_mode {
>  	TPACPI_FAN_NONE = 0,		/* No fan status or control */
>  	TPACPI_FAN_RD_ACPI_GFAN,	/* Use ACPI GFAN */
> +	TPACPI_FAN_RD_ACPI_FANG,	/* Use ACPI FANG */
>  	TPACPI_FAN_RD_TPEC,		/* Use ACPI EC regs 0x2f, 0x84-0x85 */
>  	TPACPI_FAN_RD_TPEC_NS,		/* Use non-standard ACPI EC regs (eg: L13 Yoga gen2 etc.) */
>  };
> @@ -7891,6 +7914,7 @@ enum fan_status_access_mode {
>  enum fan_control_access_mode {
>  	TPACPI_FAN_WR_NONE = 0,		/* No fan control */
>  	TPACPI_FAN_WR_ACPI_SFAN,	/* Use ACPI SFAN */
> +	TPACPI_FAN_WR_ACPI_FANW,	/* Use ACPI FANW */
>  	TPACPI_FAN_WR_TPEC,		/* Use ACPI EC reg 0x2f */
>  	TPACPI_FAN_WR_ACPI_FANS,	/* Use ACPI FANS and EC reg 0x2f */
>  };
> @@ -7924,9 +7948,13 @@ TPACPI_HANDLE(fans, ec, "FANS");	/* X31, X40, X41 */
>  TPACPI_HANDLE(gfan, ec, "GFAN",	/* 570 */
>  	   "\\FSPD",		/* 600e/x, 770e, 770x */
>  	   );			/* all others */
> +TPACPI_HANDLE(fang, ec, "FANG",	/* E531 */
> +	   );			/* all others */
>  TPACPI_HANDLE(sfan, ec, "SFAN",	/* 570 */
>  	   "JFNS",		/* 770x-JL */
>  	   );			/* all others */
> +TPACPI_HANDLE(fanw, ec, "FANW",	/* E531 */
> +	   );			/* all others */
>  
>  /*
>   * Unitialized HFSP quirk: ACPI DSDT and EC fail to initialize the
> @@ -8033,6 +8061,23 @@ static int fan_get_status(u8 *status)
>  
>  		break;
>  	}
> +	case TPACPI_FAN_RD_ACPI_FANG: {
> +		/* E531 */
> +		int mode, speed;
> +
> +		if (unlikely(!acpi_evalf(fang_handle, &mode, NULL, "dd", 0x8100)))
> +			return -EIO;
> +		if (unlikely(!acpi_evalf(fang_handle, &speed, NULL, "dd", 0x8102)))
> +			return -EIO;
> +
> +		if (likely(status)) {
> +			*status = speed * 7 / 100;
> +			if (mode < 9)
> +				*status |= TP_EC_FAN_AUTO;
> +		}
> +
> +		break;
> +	}
>  	case TPACPI_FAN_RD_TPEC:
>  		/* all except 570, 600e/x, 770e, 770x */
>  		if (unlikely(!acpi_ec_read(fan_status_offset, &s)))
> @@ -8147,6 +8192,17 @@ static int fan2_get_speed(unsigned int *speed)
>  		if (speed)
>  			*speed = lo ? FAN_RPM_CAL_CONST / lo : 0;
>  		break;
> +	case TPACPI_FAN_RD_ACPI_FANG: {
> +		/* E531 */
> +		int speed_tmp;
> +
> +		if (unlikely(!acpi_evalf(fang_handle, &speed_tmp, NULL, "dd", 0x8102)))
> +			return -EIO;
> +
> +		if (likely(speed))
> +			*speed =  speed_tmp * 65535 / 100;
> +		break;
> +	}
>  
>  	default:
>  		return -ENXIO;
> @@ -8206,6 +8262,32 @@ static int fan_set_level(int level)
>  			tp_features.fan_ctrl_status_undef = 0;
>  		break;
>  
> +	case TPACPI_FAN_WR_ACPI_FANW:
> +		if (!(level & TP_EC_FAN_AUTO) && (level < 0 || level > 7))
> +			return -EINVAL;
> +		if (level & TP_EC_FAN_FULLSPEED)
> +			return -EINVAL;
> +
> +		if (level & TP_EC_FAN_AUTO) {
> +			if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8106, 0x05)) {
> +				return -EIO;
> +			}
> +			if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8100, 0x00)) {
> +				return -EIO;
> +			}
> +		} else {
> +			if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8106, 0x45)) {
> +				return -EIO;
> +			}
> +			if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8100, 0xff)) {
> +				return -EIO;
> +			}
> +			if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8102, level * 100 / 7)) {
> +				return -EIO;
> +			}
> +		}
> +		break;
> +
>  	default:
>  		return -ENXIO;
>  	}
> @@ -8284,6 +8366,19 @@ static int fan_set_enable(void)
>  			rc = 0;
>  		break;
>  
> +	case TPACPI_FAN_WR_ACPI_FANW:
> +		if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8106, 0x05)) {
> +			rc = -EIO;
> +			break;
> +		}
> +		if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8100, 0x00)) {
> +			rc = -EIO;
> +			break;
> +		}
> +
> +		rc = 0;
> +		break;
> +
>  	default:
>  		rc = -ENXIO;
>  	}
> @@ -8326,6 +8421,22 @@ static int fan_set_disable(void)
>  			fan_control_desired_level = 0;
>  		break;
>  
> +	case TPACPI_FAN_WR_ACPI_FANW:
> +		if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8106, 0x45)) {
> +			rc = -EIO;
> +			break;
> +		}
> +		if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8100, 0xff)) {
> +			rc = -EIO;
> +			break;
> +		}
> +		if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8102, 0x00)) {
> +			rc = -EIO;
> +			break;
> +		}
> +		rc = 0;
> +		break;
> +
>  	default:
>  		rc = -ENXIO;
>  	}
> @@ -8359,6 +8470,23 @@ static int fan_set_speed(int speed)
>  			rc = -EINVAL;
>  		break;
>  
> +	case TPACPI_FAN_WR_ACPI_FANW:
> +		if (speed >= 0 && speed <= 65535) {
> +			if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8106, 0x45)) {
> +				rc = -EIO;
> +				break;
> +			}
> +			if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8100, 0xff)) {
> +				rc = -EIO;
> +				break;
> +			}
> +			if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd",
> +					0x8102, speed * 100 / 65535))
> +				rc = -EIO;
> +		} else
> +			rc = -EINVAL;
> +		break;
> +
>  	default:
>  		rc = -ENXIO;
>  	}
> @@ -8701,6 +8829,10 @@ static int __init fan_init(struct ibm_init_struct *iibm)
>  		TPACPI_ACPIHANDLE_INIT(gfan);
>  		TPACPI_ACPIHANDLE_INIT(sfan);
>  	}
> +	if (tpacpi_is_lenovo()) {
> +		TPACPI_ACPIHANDLE_INIT(fang);
> +		TPACPI_ACPIHANDLE_INIT(fanw);
> +	}
>  
>  	quirks = tpacpi_check_quirks(fan_quirk_table,
>  				     ARRAY_SIZE(fan_quirk_table));
> @@ -8720,6 +8852,9 @@ static int __init fan_init(struct ibm_init_struct *iibm)
>  	if (gfan_handle) {
>  		/* 570, 600e/x, 770e, 770x */
>  		fan_status_access_mode = TPACPI_FAN_RD_ACPI_GFAN;
> +	} else if (fang_handle) {
> +		/* E531 */
> +		fan_status_access_mode = TPACPI_FAN_RD_ACPI_FANG;
>  	} else {
>  		/* all other ThinkPads: note that even old-style
>  		 * ThinkPad ECs supports the fan control register */
> @@ -8766,6 +8901,11 @@ static int __init fan_init(struct ibm_init_struct *iibm)
>  		fan_control_access_mode = TPACPI_FAN_WR_ACPI_SFAN;
>  		fan_control_commands |=
>  		    TPACPI_FAN_CMD_LEVEL | TPACPI_FAN_CMD_ENABLE;
> +	} else if (fanw_handle) {
> +		/* E531 */
> +		fan_control_access_mode = TPACPI_FAN_WR_ACPI_FANW;
> +		fan_control_commands |=
> +		    TPACPI_FAN_CMD_LEVEL | TPACPI_FAN_CMD_SPEED | TPACPI_FAN_CMD_ENABLE;
>  	} else {
>  		if (!gfan_handle) {
>  			/* gfan without sfan means no fan control */
> @@ -8917,6 +9057,7 @@ static int fan_read(struct seq_file *m)
>  
>  	case TPACPI_FAN_RD_TPEC_NS:
>  	case TPACPI_FAN_RD_TPEC:
> +	case TPACPI_FAN_RD_ACPI_FANG:
>  		/* all except 570, 600e/x, 770e, 770x */
>  		rc = fan_get_status_safe(&status);
>  		if (rc)
> @@ -8937,7 +9078,7 @@ static int fan_read(struct seq_file *m)
>  			 * No other levels settings available
>  			 */
>  			seq_printf(m, "level:\t\t%s\n", status & FAN_NS_CTRL ? "unknown" : "auto");
> -		} else {
> +		} else if (fan_status_access_mode == TPACPI_FAN_RD_TPEC) {
>  			if (status & TP_EC_FAN_FULLSPEED)
>  				/* Disengaged mode takes precedence */
>  				seq_printf(m, "level:\t\tdisengaged\n");
diff mbox series

Patch

diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index 397b409064c9..96c58bc59018 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -7751,6 +7751,28 @@  static struct ibm_struct volume_driver_data = {
  * 	EC 0x2f (HFSP) might be available *for reading*, but do not use
  * 	it for writing.
  *
+ * TPACPI_FAN_RD_ACPI_FANG:
+ * 	ACPI FANG method: returns fan control register
+ *
+ *	Takes one parameter which is 0x8100 plus the offset to EC memory
+ *	address 0xf500 and returns the byte at this address.
+ *
+ *	0xf500:
+ *		When the value is less than 9 automatic mode is enabled
+ *	0xf502:
+ *		Contains the current fan speed from 0-100%
+ *	0xf506:
+ *		Bit 7 has to be set in order to enable manual control by
+ *		writing a value >= 9 to 0xf500
+ *
+ * TPACPI_FAN_WR_ACPI_FANW:
+ * 	ACPI FANG method: sets fan control registers
+ *
+ * 	Takes 0x8100 plus the offset to EC memory address 0xf500 and the
+ * 	value to be written there as parameters.
+ *
+ *	see TPACPI_FAN_RD_ACPI_FANG
+ *
  * TPACPI_FAN_WR_TPEC:
  * 	ThinkPad EC register 0x2f (HFSP): fan control loop mode
  * 	Supported on almost all ThinkPads
@@ -7884,6 +7906,7 @@  enum {					/* Fan control constants */
 enum fan_status_access_mode {
 	TPACPI_FAN_NONE = 0,		/* No fan status or control */
 	TPACPI_FAN_RD_ACPI_GFAN,	/* Use ACPI GFAN */
+	TPACPI_FAN_RD_ACPI_FANG,	/* Use ACPI FANG */
 	TPACPI_FAN_RD_TPEC,		/* Use ACPI EC regs 0x2f, 0x84-0x85 */
 	TPACPI_FAN_RD_TPEC_NS,		/* Use non-standard ACPI EC regs (eg: L13 Yoga gen2 etc.) */
 };
@@ -7891,6 +7914,7 @@  enum fan_status_access_mode {
 enum fan_control_access_mode {
 	TPACPI_FAN_WR_NONE = 0,		/* No fan control */
 	TPACPI_FAN_WR_ACPI_SFAN,	/* Use ACPI SFAN */
+	TPACPI_FAN_WR_ACPI_FANW,	/* Use ACPI FANW */
 	TPACPI_FAN_WR_TPEC,		/* Use ACPI EC reg 0x2f */
 	TPACPI_FAN_WR_ACPI_FANS,	/* Use ACPI FANS and EC reg 0x2f */
 };
@@ -7924,9 +7948,13 @@  TPACPI_HANDLE(fans, ec, "FANS");	/* X31, X40, X41 */
 TPACPI_HANDLE(gfan, ec, "GFAN",	/* 570 */
 	   "\\FSPD",		/* 600e/x, 770e, 770x */
 	   );			/* all others */
+TPACPI_HANDLE(fang, ec, "FANG",	/* E531 */
+	   );			/* all others */
 TPACPI_HANDLE(sfan, ec, "SFAN",	/* 570 */
 	   "JFNS",		/* 770x-JL */
 	   );			/* all others */
+TPACPI_HANDLE(fanw, ec, "FANW",	/* E531 */
+	   );			/* all others */
 
 /*
  * Unitialized HFSP quirk: ACPI DSDT and EC fail to initialize the
@@ -8033,6 +8061,23 @@  static int fan_get_status(u8 *status)
 
 		break;
 	}
+	case TPACPI_FAN_RD_ACPI_FANG: {
+		/* E531 */
+		int mode, speed;
+
+		if (unlikely(!acpi_evalf(fang_handle, &mode, NULL, "dd", 0x8100)))
+			return -EIO;
+		if (unlikely(!acpi_evalf(fang_handle, &speed, NULL, "dd", 0x8102)))
+			return -EIO;
+
+		if (likely(status)) {
+			*status = speed * 7 / 100;
+			if (mode < 9)
+				*status |= TP_EC_FAN_AUTO;
+		}
+
+		break;
+	}
 	case TPACPI_FAN_RD_TPEC:
 		/* all except 570, 600e/x, 770e, 770x */
 		if (unlikely(!acpi_ec_read(fan_status_offset, &s)))
@@ -8147,6 +8192,17 @@  static int fan2_get_speed(unsigned int *speed)
 		if (speed)
 			*speed = lo ? FAN_RPM_CAL_CONST / lo : 0;
 		break;
+	case TPACPI_FAN_RD_ACPI_FANG: {
+		/* E531 */
+		int speed_tmp;
+
+		if (unlikely(!acpi_evalf(fang_handle, &speed_tmp, NULL, "dd", 0x8102)))
+			return -EIO;
+
+		if (likely(speed))
+			*speed =  speed_tmp * 65535 / 100;
+		break;
+	}
 
 	default:
 		return -ENXIO;
@@ -8206,6 +8262,32 @@  static int fan_set_level(int level)
 			tp_features.fan_ctrl_status_undef = 0;
 		break;
 
+	case TPACPI_FAN_WR_ACPI_FANW:
+		if (!(level & TP_EC_FAN_AUTO) && (level < 0 || level > 7))
+			return -EINVAL;
+		if (level & TP_EC_FAN_FULLSPEED)
+			return -EINVAL;
+
+		if (level & TP_EC_FAN_AUTO) {
+			if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8106, 0x05)) {
+				return -EIO;
+			}
+			if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8100, 0x00)) {
+				return -EIO;
+			}
+		} else {
+			if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8106, 0x45)) {
+				return -EIO;
+			}
+			if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8100, 0xff)) {
+				return -EIO;
+			}
+			if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8102, level * 100 / 7)) {
+				return -EIO;
+			}
+		}
+		break;
+
 	default:
 		return -ENXIO;
 	}
@@ -8284,6 +8366,19 @@  static int fan_set_enable(void)
 			rc = 0;
 		break;
 
+	case TPACPI_FAN_WR_ACPI_FANW:
+		if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8106, 0x05)) {
+			rc = -EIO;
+			break;
+		}
+		if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8100, 0x00)) {
+			rc = -EIO;
+			break;
+		}
+
+		rc = 0;
+		break;
+
 	default:
 		rc = -ENXIO;
 	}
@@ -8326,6 +8421,22 @@  static int fan_set_disable(void)
 			fan_control_desired_level = 0;
 		break;
 
+	case TPACPI_FAN_WR_ACPI_FANW:
+		if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8106, 0x45)) {
+			rc = -EIO;
+			break;
+		}
+		if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8100, 0xff)) {
+			rc = -EIO;
+			break;
+		}
+		if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8102, 0x00)) {
+			rc = -EIO;
+			break;
+		}
+		rc = 0;
+		break;
+
 	default:
 		rc = -ENXIO;
 	}
@@ -8359,6 +8470,23 @@  static int fan_set_speed(int speed)
 			rc = -EINVAL;
 		break;
 
+	case TPACPI_FAN_WR_ACPI_FANW:
+		if (speed >= 0 && speed <= 65535) {
+			if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8106, 0x45)) {
+				rc = -EIO;
+				break;
+			}
+			if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd", 0x8100, 0xff)) {
+				rc = -EIO;
+				break;
+			}
+			if (!acpi_evalf(fanw_handle, NULL, NULL, "vdd",
+					0x8102, speed * 100 / 65535))
+				rc = -EIO;
+		} else
+			rc = -EINVAL;
+		break;
+
 	default:
 		rc = -ENXIO;
 	}
@@ -8701,6 +8829,10 @@  static int __init fan_init(struct ibm_init_struct *iibm)
 		TPACPI_ACPIHANDLE_INIT(gfan);
 		TPACPI_ACPIHANDLE_INIT(sfan);
 	}
+	if (tpacpi_is_lenovo()) {
+		TPACPI_ACPIHANDLE_INIT(fang);
+		TPACPI_ACPIHANDLE_INIT(fanw);
+	}
 
 	quirks = tpacpi_check_quirks(fan_quirk_table,
 				     ARRAY_SIZE(fan_quirk_table));
@@ -8720,6 +8852,9 @@  static int __init fan_init(struct ibm_init_struct *iibm)
 	if (gfan_handle) {
 		/* 570, 600e/x, 770e, 770x */
 		fan_status_access_mode = TPACPI_FAN_RD_ACPI_GFAN;
+	} else if (fang_handle) {
+		/* E531 */
+		fan_status_access_mode = TPACPI_FAN_RD_ACPI_FANG;
 	} else {
 		/* all other ThinkPads: note that even old-style
 		 * ThinkPad ECs supports the fan control register */
@@ -8766,6 +8901,11 @@  static int __init fan_init(struct ibm_init_struct *iibm)
 		fan_control_access_mode = TPACPI_FAN_WR_ACPI_SFAN;
 		fan_control_commands |=
 		    TPACPI_FAN_CMD_LEVEL | TPACPI_FAN_CMD_ENABLE;
+	} else if (fanw_handle) {
+		/* E531 */
+		fan_control_access_mode = TPACPI_FAN_WR_ACPI_FANW;
+		fan_control_commands |=
+		    TPACPI_FAN_CMD_LEVEL | TPACPI_FAN_CMD_SPEED | TPACPI_FAN_CMD_ENABLE;
 	} else {
 		if (!gfan_handle) {
 			/* gfan without sfan means no fan control */
@@ -8917,6 +9057,7 @@  static int fan_read(struct seq_file *m)
 
 	case TPACPI_FAN_RD_TPEC_NS:
 	case TPACPI_FAN_RD_TPEC:
+	case TPACPI_FAN_RD_ACPI_FANG:
 		/* all except 570, 600e/x, 770e, 770x */
 		rc = fan_get_status_safe(&status);
 		if (rc)
@@ -8937,7 +9078,7 @@  static int fan_read(struct seq_file *m)
 			 * No other levels settings available
 			 */
 			seq_printf(m, "level:\t\t%s\n", status & FAN_NS_CTRL ? "unknown" : "auto");
-		} else {
+		} else if (fan_status_access_mode == TPACPI_FAN_RD_TPEC) {
 			if (status & TP_EC_FAN_FULLSPEED)
 				/* Disengaged mode takes precedence */
 				seq_printf(m, "level:\t\tdisengaged\n");