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Revert "ACPI: Pass the same capabilities to the _OSC regardless of the query flag"

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commit 2ca8e62852 upstream.

Revert commit 159d8c274f ("ACPI: Pass the same capabilities to the
_OSC regardless of the query flag") which caused legitimate usage
scenarios (when the platform firmware does not want the OS to control
certain platform features controlled by the system bus scope _OSC) to
break and was misguided by some misleading language in the _OSC
definition in the ACPI specification (in particular, Section 6.2.11.1.3
"Sequence of _OSC Calls" that contradicts other perts of the _OSC
definition).

Link: https://lore.kernel.org/linux-acpi/CAJZ5v0iStA0JmO0H3z+VgQsVuQONVjKPpw0F5HKfiq=Gb6B5yw@mail.gmail.com
Reported-by: Mario Limonciello <Mario.Limonciello@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mario Limonciello <mario.limonciello@amd.com>
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Rafael J. Wysocki
2022-03-16 13:37:44 +01:00
committed by Greg Kroah-Hartman
parent b6094744e2
commit 2e2eb55823
1 changed files with 19 additions and 8 deletions
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drivers/acpi/bus.c
+19 -8
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@@ -332,21 +332,32 @@ static void acpi_bus_osc_negotiate_platform_control(void)
if (ACPI_FAILURE(acpi_run_osc(handle, &context)))
return;
kfree(context.ret.pointer);
capbuf_ret = context.ret.pointer;
if (context.ret.length <= OSC_SUPPORT_DWORD) {
kfree(context.ret.pointer);
return;
}
/* Now run _OSC again with query flag clear */
/*
* Now run _OSC again with query flag clear and with the caps
* supported by both the OS and the platform.
*/
capbuf[OSC_QUERY_DWORD] = 0;
capbuf[OSC_SUPPORT_DWORD] = capbuf_ret[OSC_SUPPORT_DWORD];
kfree(context.ret.pointer);
if (ACPI_FAILURE(acpi_run_osc(handle, &context)))
return;
capbuf_ret = context.ret.pointer;
osc_sb_apei_support_acked =
capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_APEI_SUPPORT;
osc_pc_lpi_support_confirmed =
capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_PCLPI_SUPPORT;
osc_sb_native_usb4_support_confirmed =
capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_NATIVE_USB4_SUPPORT;
if (context.ret.length > OSC_SUPPORT_DWORD) {
osc_sb_apei_support_acked =
capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_APEI_SUPPORT;
osc_pc_lpi_support_confirmed =
capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_PCLPI_SUPPORT;
osc_sb_native_usb4_support_confirmed =
capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_NATIVE_USB4_SUPPORT;
}
kfree(context.ret.pointer);
}