From aa2fef6f40e6ccc22e932b36898f260f0e5a021a Mon Sep 17 00:00:00 2001
From: Mark Pearson <markpearson@lenovo.com>
Date: Mon, 2 May 2022 15:12:00 -0400
Subject: [PATCH] platform/x86: thinkpad_acpi: Correct dual fan probe
Git-commit: aa2fef6f40e6ccc22e932b36898f260f0e5a021a
Patch-mainline: v5.18-rc7
References: bsc#1210050

There was an issue with the dual fan probe whereby the probe was
failing as it assuming that second_fan support was not available.

Corrected the logic so the probe works correctly. Cleaned up so
quirks only used if 2nd fan not detected.

Tested on X1 Carbon 10 (2 fans), X1 Carbon 9 (2 fans) and T490 (1 fan)

Signed-off-by: Mark Pearson <markpearson@lenovo.com>
Link: https://lore.kernel.org/r/20220502191200.63470-1-markpearson@lenovo.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/platform/x86/thinkpad_acpi.c | 23 +++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index 8180d7789f56..e6cb4a14cdd4 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -8880,24 +8880,27 @@ static int __init fan_init(struct ibm_init_struct *iibm)
 			fan_status_access_mode = TPACPI_FAN_RD_TPEC;
 			if (quirks & TPACPI_FAN_Q1)
 				fan_quirk1_setup();
-			if (quirks & TPACPI_FAN_2FAN) {
-				tp_features.second_fan = 1;
-				pr_info("secondary fan support enabled\n");
-			}
-			if (quirks & TPACPI_FAN_2CTL) {
-				tp_features.second_fan = 1;
-				tp_features.second_fan_ctl = 1;
-				pr_info("secondary fan control enabled\n");
-			}
 			/* Try and probe the 2nd fan */
+			tp_features.second_fan = 1; /* needed for get_speed to work */
 			res = fan2_get_speed(&speed);
 			if (res >= 0) {
 				/* It responded - so let's assume it's there */
 				tp_features.second_fan = 1;
 				tp_features.second_fan_ctl = 1;
 				pr_info("secondary fan control detected & enabled\n");
+			} else {
+				/* Fan not auto-detected */
+				tp_features.second_fan = 0;
+				if (quirks & TPACPI_FAN_2FAN) {
+					tp_features.second_fan = 1;
+					pr_info("secondary fan support enabled\n");
+				}
+				if (quirks & TPACPI_FAN_2CTL) {
+					tp_features.second_fan = 1;
+					tp_features.second_fan_ctl = 1;
+					pr_info("secondary fan control enabled\n");
+				}
 			}
-
 		} else {
 			pr_err("ThinkPad ACPI EC access misbehaving, fan status and control unavailable\n");
 			return -ENODEV;
-- 
2.35.3