From c15f86856bec5bbf9a5ea909ce5ccc5b05744eb1 Mon Sep 17 00:00:00 2001
From: Hans de Goede <hdegoede@redhat.com>
Date: Sun, 21 Nov 2021 20:11:23 +0100
Subject: [PATCH] platform/x86: thinkpad_acpi: Accept ibm_init_struct.init() returning -ENODEV
Git-commit: c15f86856bec5bbf9a5ea909ce5ccc5b05744eb1
Patch-mainline: v5.17-rc1
References: bsc#1210050
Commit 79f960e29cfc ("platform/x86: thinkpad_acpi: Convert platform driver
to use dev_groups") accidentally modified tpacpi_kbdlang_init() causing it
to return -ENODEV instead of 0 on machines without kbdlang support
(which are most of them).
ibm_init() sees this -ENODEV as an error causing the entire module to not
load, not good.
Note that technically tpacpi_kbdlang_init() was already buggy before, it
should have returned 1 instead of 0 if the feature is not present.
Rather then fixing tpacpi_kbdlang_init() though, IMHO it is bettter to
just make ibm_init() treat -ENODEV as 1 to fix the issue; and then in
a followup commit also change all the existing "return 1"s from
ibm_init_struct.init() callbacks to "return -ENODEV" as -ENODEV clearly
states what it going on where as a magic return of "1" requires a deep
dive into the code to figure out what is going on.
This will also allow removing some extra ifs to translate -ENODEV to
return 1 in a couple of init() callbacks.
Fixes: 79f960e29cfc ("platform/x86: thinkpad_acpi: Convert platform driver to use dev_groups")
Cc: Len Baker <len.baker@gmx.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20211121191129.256713-2-hdegoede@redhat.com
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/platform/x86/thinkpad_acpi.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index 37aadc64d4e0..9e296b436bea 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -10685,8 +10685,8 @@ static int __init ibm_init(struct ibm_init_struct *iibm)
if (iibm->init) {
ret = iibm->init(iibm);
- if (ret > 0)
- return 0; /* probe failed */
+ if (ret > 0 || ret == -ENODEV)
+ return 0; /* subdriver functionality not available */
if (ret)
return ret;
--
2.35.3