[PATCH v3 4/7] ACPI / osi: Fix default _OSI(Darwin) support

From: Lv Zheng
Date: Tue May 03 2016 - 04:48:52 EST


From: Chen Yu <yu.c.chen@xxxxxxxxx>

The following commit always reports positive value when Apple hardware
queries _OSI("Darwin"):
Commit: 7bc5a2bad0b8d9d1ac9f7b8b33150e4ddf197334
Subject: ACPI: Support _OSI("Darwin") correctly
However since this implementation places the judgement in runtime, it
breaks acpi_osi=!Darwin and cannot return unsupported for _OSI("WinXXX")
invoked before invoking _OSI("Darwin").

This patch fixes the issues by reverting the wrong support and implementing
the default behavior of _OSI("Darwin")/_OSI("WinXXX") on Apple hardware via
DMI matching.

Fixes: 7bc5a2bad0b8 ("ACPI: Support _OSI("Darwin") correctly")
Cc: <stable@xxxxxxxxxxxxxxx> # 3.18+
Link: https://bugzilla.kernel.org/show_bug.cgi?id=92111
Reported-and-tested-by: Lukas Wunner <lukas@xxxxxxxxx>
Signed-off-by: Chen Yu <yu.c.chen@xxxxxxxxx>
Signed-off-by: Lv Zheng <lv.zheng@xxxxxxxxx>
---
drivers/acpi/blacklist.c | 23 ++++++++++++++++++
drivers/acpi/osl.c | 58 ++++++++++++++++++++++++++++++++++++++++------
include/linux/acpi.h | 1 +
3 files changed, 75 insertions(+), 7 deletions(-)

diff --git a/drivers/acpi/blacklist.c b/drivers/acpi/blacklist.c
index 96809cd..45390a9 100644
--- a/drivers/acpi/blacklist.c
+++ b/drivers/acpi/blacklist.c
@@ -133,6 +133,11 @@ int __init acpi_blacklisted(void)
return blacklisted;
}
#ifdef CONFIG_DMI
+static int __init dmi_enable_osi_darwin(const struct dmi_system_id *d)
+{
+ acpi_dmi_osi_darwin(1, d); /* enable */
+ return 0;
+}
static int __init dmi_enable_osi_linux(const struct dmi_system_id *d)
{
acpi_dmi_osi_linux(1, d); /* enable */
@@ -331,6 +336,24 @@ static struct dmi_system_id acpi_osi_dmi_table[] __initdata = {
},
},

+ /*
+ * Enable _OSI("Darwin") for all apple platforms.
+ */
+ {
+ .callback = dmi_enable_osi_darwin,
+ .ident = "Apple hardware",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+ },
+ },
+ {
+ .callback = dmi_enable_osi_darwin,
+ .ident = "Apple hardware",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Computer, Inc."),
+ },
+ },
+
#ifdef CONFIG_ACPI_REV_OVERRIDE_POSSIBLE
/*
* DELL XPS 13 (2015) switches sound between HDA and I2S
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index fbedea7..5dd2a79 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -135,6 +135,9 @@ static struct acpi_osi_config {
unsigned int linux_enable:1;
unsigned int linux_dmi:1;
unsigned int linux_cmdline:1;
+ unsigned int darwin_enable:1;
+ unsigned int darwin_dmi:1;
+ unsigned int darwin_cmdline:1;
u8 default_disabling;
} osi_config = {0, 0, 0, 0};

@@ -150,13 +153,12 @@ static u32 acpi_osi_handler(acpi_string interface, u32 supported)
}

if (!strcmp("Darwin", interface)) {
- /*
- * Apple firmware will behave poorly if it receives positive
- * answers to "Darwin" and any other OS. Respond positively
- * to Darwin and then disable all other vendor strings.
- */
- acpi_update_interfaces(ACPI_DISABLE_ALL_VENDOR_STRINGS);
- supported = ACPI_UINT32_MAX;
+
+ printk_once(KERN_NOTICE PREFIX
+ "BIOS _OSI(Darwin) query %s%s\n",
+ osi_config.darwin_enable ? "honored" : "ignored",
+ osi_config.darwin_cmdline ? " via cmdline" :
+ osi_config.darwin_dmi ? " via DMI" : "");
}

return supported;
@@ -1509,6 +1511,44 @@ void __init acpi_osi_setup(char *str)
}
}

+static void __init set_osi_darwin(unsigned int enable)
+{
+ if (osi_config.darwin_enable != enable)
+ osi_config.darwin_enable = enable;
+
+ if (enable) {
+ acpi_osi_setup("!");
+ acpi_osi_setup("Darwin");
+ } else {
+ acpi_osi_setup("!!");
+ acpi_osi_setup("!Darwin");
+ }
+}
+
+static void __init acpi_cmdline_osi_darwin(unsigned int enable)
+{
+ /* cmdline set the default and override DMI */
+ osi_config.darwin_cmdline = 1;
+ osi_config.darwin_dmi = 0;
+ set_osi_darwin(enable);
+
+ return;
+}
+
+void __init acpi_dmi_osi_darwin(int enable, const struct dmi_system_id *d)
+{
+ printk(KERN_NOTICE PREFIX "DMI detected: %s\n", d->ident);
+
+ if (enable == -1)
+ return;
+
+ /* DMI knows that this box asks OSI(Darwin) */
+ osi_config.darwin_dmi = 1;
+ set_osi_darwin(enable);
+
+ return;
+}
+
static void __init set_osi_linux(unsigned int enable)
{
if (osi_config.linux_enable != enable)
@@ -1596,6 +1636,10 @@ static int __init osi_setup(char *str)
acpi_cmdline_osi_linux(1);
else if (str && !strcmp("!Linux", str))
acpi_cmdline_osi_linux(0);
+ else if (str && !strcmp("Darwin", str))
+ acpi_cmdline_osi_darwin(1);
+ else if (str && !strcmp("!Darwin", str))
+ acpi_cmdline_osi_darwin(0);
else
acpi_osi_setup(str);

diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index be5d206..8fd3a82 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -354,6 +354,7 @@ extern char acpi_video_backlight_string[];
extern long acpi_is_video_device(acpi_handle handle);
extern int acpi_blacklisted(void);
extern void acpi_dmi_osi_linux(int enable, const struct dmi_system_id *d);
+extern void acpi_dmi_osi_darwin(int enable, const struct dmi_system_id *d);
extern void acpi_osi_setup(char *str);
extern bool acpi_osi_is_win8(void);

--
1.7.10