From: Armin Wolf Date: Tue, 29 Jul 2025 06:20:38 +0000 (+0200) Subject: ACPI: EC: Relax sanity check of the ECDT ID string X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=963e22c084c2b6097e1e635d29c6336881f67708;p=users%2Fjedix%2Flinux-maple.git ACPI: EC: Relax sanity check of the ECDT ID string It turns out that the ECDT table inside the ThinkBook 14 G7 IML contains a valid EC description but an invalid ID string ("_SB.PC00.LPCB.EC0"). Ignoring this ECDT based on the invalid ID string prevents the kernel from detecting the built-in touchpad, so relax the sanity check of the ID string and only reject ECDTs with empty ID strings. Reported-by: Ilya K Fixes: 7a0d59f6a913 ("ACPI: EC: Ignore ECDT tables with an invalid ID string") Signed-off-by: Armin Wolf Tested-by: Ilya K Link: https://patch.msgid.link/20250729062038.303734-1-W_Armin@gmx.de Cc: 6.16+ # 6.16+ Signed-off-by: Rafael J. Wysocki --- diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c index 75c7db8b156a2..7855bbf752b1e 100644 --- a/drivers/acpi/ec.c +++ b/drivers/acpi/ec.c @@ -2033,7 +2033,7 @@ void __init acpi_ec_ecdt_probe(void) goto out; } - if (!strstarts(ecdt_ptr->id, "\\")) { + if (!strlen(ecdt_ptr->id)) { /* * The ECDT table on some MSI notebooks contains invalid data, together * with an empty ID string (""). @@ -2042,9 +2042,13 @@ void __init acpi_ec_ecdt_probe(void) * a "fully qualified reference to the (...) embedded controller device", * so this string always has to start with a backslash. * - * By verifying this we can avoid such faulty ECDT tables in a safe way. + * However some ThinkBook machines have a ECDT table with a valid EC + * description but an invalid ID string ("_SB.PC00.LPCB.EC0"). + * + * Because of this we only check if the ID string is empty in order to + * avoid the obvious cases. */ - pr_err(FW_BUG "Ignoring ECDT due to invalid ID string \"%s\"\n", ecdt_ptr->id); + pr_err(FW_BUG "Ignoring ECDT due to empty ID string\n"); goto out; }