From a0a37862a4e1844793d39aca9ccb8fecbdcb8659 Mon Sep 17 00:00:00 2001 From: Mika Westerberg Date: Mon, 23 Apr 2018 14:16:03 +0300 Subject: [PATCH 1/3] ACPI / watchdog: Prefer iTCO_wdt on Lenovo Z50-70 WDAT table on Lenovo Z50-70 is using RTC SRAM (ports 0x70 and 0x71) to store state of the timer. This conflicts with Linux RTC driver (rtc-cmos.c) who fails to reserve those ports for itself preventing RTC from functioning. In addition the WDAT table seems not to be fully functional because it does not reset the system when the watchdog times out. On this system iTCO_wdt works just fine so we simply prefer to use it instead of WDAT. This makes RTC working again and also results working watchdog via iTCO_wdt. Reported-by: Peter Milley Link: https://bugzilla.kernel.org/show_bug.cgi?id=199033 Signed-off-by: Mika Westerberg Signed-off-by: Rafael J. Wysocki --- drivers/acpi/acpi_watchdog.c | 59 ++++++++++++++++++++++++++++++------ 1 file changed, 49 insertions(+), 10 deletions(-) diff --git a/drivers/acpi/acpi_watchdog.c b/drivers/acpi/acpi_watchdog.c index ebb626ffb5fa..4bde16fb97d8 100644 --- a/drivers/acpi/acpi_watchdog.c +++ b/drivers/acpi/acpi_watchdog.c @@ -12,23 +12,64 @@ #define pr_fmt(fmt) "ACPI: watchdog: " fmt #include +#include #include #include #include "internal.h" +static const struct dmi_system_id acpi_watchdog_skip[] = { + { + /* + * On Lenovo Z50-70 there are two issues with the WDAT + * table. First some of the instructions use RTC SRAM + * to store persistent information. This does not work well + * with Linux RTC driver. Second, more important thing is + * that the instructions do not actually reset the system. + * + * On this particular system iTCO_wdt seems to work just + * fine so we prefer that over WDAT for now. + * + * See also https://bugzilla.kernel.org/show_bug.cgi?id=199033. + */ + .ident = "Lenovo Z50-70", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), + DMI_MATCH(DMI_PRODUCT_NAME, "20354"), + DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo Z50-70"), + }, + }, + {} +}; + +static const struct acpi_table_wdat *acpi_watchdog_get_wdat(void) +{ + const struct acpi_table_wdat *wdat = NULL; + acpi_status status; + + if (acpi_disabled) + return NULL; + + if (dmi_check_system(acpi_watchdog_skip)) + return NULL; + + status = acpi_get_table(ACPI_SIG_WDAT, 0, + (struct acpi_table_header **)&wdat); + if (ACPI_FAILURE(status)) { + /* It is fine if there is no WDAT */ + return NULL; + } + + return wdat; +} + /** * Returns true if this system should prefer ACPI based watchdog instead of * the native one (which are typically the same hardware). */ bool acpi_has_watchdog(void) { - struct acpi_table_header hdr; - - if (acpi_disabled) - return false; - - return ACPI_SUCCESS(acpi_get_table_header(ACPI_SIG_WDAT, 0, &hdr)); + return !!acpi_watchdog_get_wdat(); } EXPORT_SYMBOL_GPL(acpi_has_watchdog); @@ -41,12 +82,10 @@ void __init acpi_watchdog_init(void) struct platform_device *pdev; struct resource *resources; size_t nresources = 0; - acpi_status status; int i; - status = acpi_get_table(ACPI_SIG_WDAT, 0, - (struct acpi_table_header **)&wdat); - if (ACPI_FAILURE(status)) { + wdat = acpi_watchdog_get_wdat(); + if (!wdat) { /* It is fine if there is no WDAT */ return; } From ac1e55b1fdb27c1b07a0a6fe519f1291ff1e7d40 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Mon, 23 Apr 2018 11:16:56 +0200 Subject: [PATCH 2/3] ACPI / button: make module loadable when booted in non-ACPI mode Modules such as nouveau.ko and i915.ko have a link time dependency on acpi_lid_open(), and due to its use of acpi_bus_register_driver(), the button.ko module that provides it is only loadable when booted in ACPI mode. However, the ACPI button driver can be built into the core kernel as well, in which case the dependency can always be satisfied, and the dependent modules can be loaded regardless of whether the system was booted in ACPI mode or not. So let's fix this asymmetry by making the ACPI button driver loadable as a module even if not booted in ACPI mode, so it can provide the acpi_lid_open() symbol in the same way as when built into the kernel. Signed-off-by: Ard Biesheuvel [ rjw: Minor adjustments of comments, whitespace and names. ] Signed-off-by: Rafael J. Wysocki --- drivers/acpi/button.c | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c index e1eee7a60fad..f1cc4f9d31cd 100644 --- a/drivers/acpi/button.c +++ b/drivers/acpi/button.c @@ -635,4 +635,26 @@ module_param_call(lid_init_state, NULL, 0644); MODULE_PARM_DESC(lid_init_state, "Behavior for reporting LID initial state"); -module_acpi_driver(acpi_button_driver); +static int acpi_button_register_driver(struct acpi_driver *driver) +{ + /* + * Modules such as nouveau.ko and i915.ko have a link time dependency + * on acpi_lid_open(), and would therefore not be loadable on ACPI + * capable kernels booted in non-ACPI mode if the return value of + * acpi_bus_register_driver() is returned from here with ACPI disabled + * when this driver is built as a module. + */ + if (acpi_disabled) + return 0; + + return acpi_bus_register_driver(driver); +} + +static void acpi_button_unregister_driver(struct acpi_driver *driver) +{ + if (!acpi_disabled) + acpi_bus_unregister_driver(driver); +} + +module_driver(acpi_button_driver, acpi_button_register_driver, + acpi_button_unregister_driver); From 53fa1f6e8a5958da698a31edf366ffe90596b490 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Tue, 17 Apr 2018 18:23:50 +0200 Subject: [PATCH 3/3] ACPI / video: Only default only_lcd to true on Win8-ready _desktops_ Commit 5928c281524f (ACPI / video: Default lcd_only to true on Win8-ready and newer machines) made only_lcd default to true on all machines where acpi_osi_is_win8() returns true, including laptops. The purpose of this is to avoid the bogus / non-working acpi backlight interface which many newer BIOS-es define on desktop machines. But this is causing a regression on some laptops, specifically on the Dell XPS 13 2013 model, which does not have the LCD flag set for its fully functional ACPI backlight interface. Rather then DMI quirking our way out of this, this commits changes the logic for setting only_lcd to true, to only do this on machines with a desktop (or server) dmi chassis-type. Note that we cannot simply only check the chassis-type and not register the backlight interface based on that as there are some laptops and tablets which have their chassis-type set to "3" aka desktop. Hopefully the combination of checking the LCD flag, but only on devices with a desktop(ish) chassis-type will avoid the needs for DMI quirks for this, or at least limit the amount of DMI quirks which we need to a minimum. Fixes: 5928c281524f (ACPI / video: Default lcd_only to true on Win8-ready and newer machines) Reported-and-tested-by: James Hogan Signed-off-by: Hans de Goede Cc: 4.15+ # 4.15+ Signed-off-by: Rafael J. Wysocki --- drivers/acpi/acpi_video.c | 27 +++++++++++++++++++++++++-- 1 file changed, 25 insertions(+), 2 deletions(-) diff --git a/drivers/acpi/acpi_video.c b/drivers/acpi/acpi_video.c index 76fb96966f7b..2f2e737be0f8 100644 --- a/drivers/acpi/acpi_video.c +++ b/drivers/acpi/acpi_video.c @@ -2123,6 +2123,25 @@ static int __init intel_opregion_present(void) return opregion; } +static bool dmi_is_desktop(void) +{ + const char *chassis_type; + + chassis_type = dmi_get_system_info(DMI_CHASSIS_TYPE); + if (!chassis_type) + return false; + + if (!strcmp(chassis_type, "3") || /* 3: Desktop */ + !strcmp(chassis_type, "4") || /* 4: Low Profile Desktop */ + !strcmp(chassis_type, "5") || /* 5: Pizza Box */ + !strcmp(chassis_type, "6") || /* 6: Mini Tower */ + !strcmp(chassis_type, "7") || /* 7: Tower */ + !strcmp(chassis_type, "11")) /* 11: Main Server Chassis */ + return true; + + return false; +} + int acpi_video_register(void) { int ret = 0; @@ -2143,8 +2162,12 @@ int acpi_video_register(void) * win8 ready (where we also prefer the native backlight driver, so * normally the acpi_video code should not register there anyways). */ - if (only_lcd == -1) - only_lcd = acpi_osi_is_win8(); + if (only_lcd == -1) { + if (dmi_is_desktop() && acpi_osi_is_win8()) + only_lcd = true; + else + only_lcd = false; + } dmi_check_system(video_dmi_table);