diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c index 1682f8b454a2..a52cb28c40d8 100644 --- a/drivers/acpi/bus.c +++ b/drivers/acpi/bus.c @@ -282,9 +282,9 @@ bool osc_pc_lpi_support_confirmed; EXPORT_SYMBOL_GPL(osc_pc_lpi_support_confirmed); static u8 sb_uuid_str[] = "0811B06E-4A27-44F9-8D60-3CBBC22E7B48"; -static void acpi_bus_osc_support(void) +static void acpi_bus_osc_negotiate_platform_control(void) { - u32 capbuf[2]; + u32 capbuf[2], *capbuf_ret; struct acpi_osc_context context = { .uuid_str = sb_uuid_str, .rev = 1, @@ -321,17 +321,36 @@ static void acpi_bus_osc_support(void) capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_APEI_SUPPORT; if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle))) return; - if (ACPI_SUCCESS(acpi_run_osc(handle, &context))) { - u32 *capbuf_ret = context.ret.pointer; - 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; - } + + if (ACPI_FAILURE(acpi_run_osc(handle, &context))) + return; + + capbuf_ret = context.ret.pointer; + if (context.ret.length <= OSC_SUPPORT_DWORD) { kfree(context.ret.pointer); + return; } - /* do we need to check other returned cap? Sounds no */ + + /* + * 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; + 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; + } + + kfree(context.ret.pointer); } /* -------------------------------------------------------------------------- @@ -1168,7 +1187,7 @@ static int __init acpi_bus_init(void) * _OSC method may exist in module level code, * so it must be run after ACPI_FULL_INITIALIZATION */ - acpi_bus_osc_support(); + acpi_bus_osc_negotiate_platform_control(); /* * _PDC control method may load dynamic SSDT tables,