x86/init: Add i8042 state to the platform data

Add i8042 state to the platform data to help i8042 driver make decision
whether to probe for i8042 or not. We recognize 3 states: platform/subarch
ca not possible have i8042 (as is the case with Inrel MID platform),
firmware (such as ACPI) reports that i8042 is absent from the device,
or i8042 may be present and the driver should probe for it.

The intent is to allow i8042 driver abort initialization on x86 if PNP data
(absence of both keyboard and mouse PNP devices) agrees with firmware data.

It will also allow us to remove i8042_detect later.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Tested-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Marcos Paulo de Souza <marcos.souza.org@gmail.com>
Cc: linux-input@vger.kernel.org
Link: http://lkml.kernel.org/r/1481317061-31486-2-git-send-email-dmitry.torokhov@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h
index 6ba79317844138672dfe7de27254425e20630b5b..c4d09c797cf7cd1821317a89c6dbff63c289713b 100644 (file)
--- a/arch/x86/include/asm/x86_init.h
+++ b/arch/x86/include/asm/x86_init.h
@@ -164,9 +164,26 @@ struct x86_legacy_devices {
        int pnpbios;
 };
 
+/**
+ * enum x86_legacy_i8042_state - i8042 keyboard controller state
+ * @X86_LEGACY_I8042_PLATFORM_ABSENT: the controller is always absent on
+ *     given platform/subarch.
+ * @X86_LEGACY_I8042_FIRMWARE_ABSENT: firmware reports that the controller
+ *     is absent.
+ * @X86_LEGACY_i8042_EXPECTED_PRESENT: the controller is likely to be
+ *     present, the i8042 driver should probe for controller existence.
+ */
+enum x86_legacy_i8042_state {
+       X86_LEGACY_I8042_PLATFORM_ABSENT,
+       X86_LEGACY_I8042_FIRMWARE_ABSENT,
+       X86_LEGACY_I8042_EXPECTED_PRESENT,
+};
+
 /**
  * struct x86_legacy_features - legacy x86 features
  *
+ * @i8042: indicated if we expect the device to have i8042 controller
+ *     present.
  * @rtc: this device has a CMOS real-time clock present
  * @reserve_bios_regions: boot code will search for the EBDA address and the
  *     start of the 640k - 1M BIOS region.  If false, the platform must
@@ -175,6 +192,7 @@ struct x86_legacy_devices {
  *     documentation for further details.
  */
 struct x86_legacy_features {
+       enum x86_legacy_i8042_state i8042;
        int rtc;
        int reserve_bios_regions;
        struct x86_legacy_devices devices;

diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 6f65b0eed384c6b276d26b44aeb0c535d6b9db3e..64422f850e95e2da7991ded073041f5df5b4dfae 100644 (file)
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -930,6 +930,13 @@ static int __init acpi_parse_fadt(struct acpi_table_header *table)
                x86_platform.legacy.devices.pnpbios = 0;
        }
 
+       if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&
+           !(acpi_gbl_FADT.boot_flags & ACPI_FADT_8042) &&
+           x86_platform.legacy.i8042 != X86_LEGACY_I8042_PLATFORM_ABSENT) {
+               pr_debug("ACPI: i8042 controller is absent\n");
+               x86_platform.legacy.i8042 = X86_LEGACY_I8042_FIRMWARE_ABSENT;
+       }
+
        if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_CMOS_RTC) {
                pr_debug("ACPI: not registering RTC platform device\n");
                x86_platform.legacy.rtc = 0;

diff --git a/arch/x86/kernel/platform-quirks.c b/arch/x86/kernel/platform-quirks.c
index 24a50301f1504a3560066e25ea9fa0ddc0d8fdaa..91271122f0dfb947e1b1b68cddeb505053fd9425 100644 (file)
--- a/arch/x86/kernel/platform-quirks.c
+++ b/arch/x86/kernel/platform-quirks.c
@@ -6,6 +6,7 @@
 
 void __init x86_early_init_platform_quirks(void)
 {
+       x86_platform.legacy.i8042 = X86_LEGACY_I8042_EXPECTED_PRESENT;
        x86_platform.legacy.rtc = 1;
        x86_platform.legacy.reserve_bios_regions = 0;
        x86_platform.legacy.devices.pnpbios = 1;
@@ -16,10 +17,14 @@ void __init x86_early_init_platform_quirks(void)
                break;
        case X86_SUBARCH_XEN:
        case X86_SUBARCH_LGUEST:
+               x86_platform.legacy.devices.pnpbios = 0;
+               x86_platform.legacy.rtc = 0;
+               break;
        case X86_SUBARCH_INTEL_MID:
        case X86_SUBARCH_CE4100:
                x86_platform.legacy.devices.pnpbios = 0;
                x86_platform.legacy.rtc = 0;
+               x86_platform.legacy.i8042 = X86_LEGACY_I8042_PLATFORM_ABSENT;
                break;
        }