Both nouveau and i915, the only 2 kernel space lid notification listeners, invoke acpi_lid_open() API to obtain _LID returning value instead of using the notified value. So kernel graphics drivers are only interested in _LID return value, hence this patch makes this logic explicit in button driver.
However the preference may because kernel graphics drivers do not want to receive non-bios notifications. Thus this patch also adds a global variable to allow button driver to stop notifying non-bios notifications. This is a no-op cleanup as the default behaviors are kept unchanged, but may: 1. improve button.lid_init_state=method by introducing a possibility to allow kernel graphics driver to reduce redundant _LID evaluations, and 2. improve button.lid_init_state=open/method by introducing a possibility to stop notifying faked non bios events. Cc: Benjamin Tissoires <[email protected]> Cc: Peter Hutterer <[email protected]> Signed-off-by: Lv Zheng <[email protected]> --- drivers/acpi/button.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) Index: linux-acpica/drivers/acpi/button.c =================================================================== --- linux-acpica.orig/drivers/acpi/button.c +++ linux-acpica/drivers/acpi/button.c @@ -119,6 +119,7 @@ static u8 lid_init_state = ACPI_BUTTON_L static unsigned long lid_report_interval __read_mostly = 500; module_param(lid_report_interval, ulong, 0644); MODULE_PARM_DESC(lid_report_interval, "Interval (ms) between lid key events"); +static bool lid_notify_non_bios_events = true; /* -------------------------------------------------------------------------- FS Interface (/proc) @@ -224,7 +225,17 @@ static void acpi_lid_notify_state(struct if (state) pm_wakeup_hard_event(&device->dev); - acpi_lid_notifier_call(device, state); + if (is_bios_event || lid_notify_non_bios_events) { + /* + * The kernel drivers are only interested in the _LID + * return value. But there are cases "state" is not a _LID + * return value, so correct it before notifying. + */ + if (!is_bios_event && + lid_init_state != ACPI_BUTTON_LID_INIT_METHOD) + state = acpi_lid_evaluate_state(device); + acpi_lid_notifier_call(device, state); + } } static int acpi_button_state_seq_show(struct seq_file *seq, void *offset) @@ -573,13 +584,13 @@ static int param_set_lid_init_state(cons if (!strncmp(val, "open", sizeof("open") - 1)) { lid_init_state = ACPI_BUTTON_LID_INIT_OPEN; - pr_info("Notify initial lid state as open\n"); + pr_info("Report initial lid state as open to input layer\n"); } else if (!strncmp(val, "method", sizeof("method") - 1)) { lid_init_state = ACPI_BUTTON_LID_INIT_METHOD; - pr_info("Notify initial lid state with _LID return value\n"); + pr_info("Report initial lid state with _LID return value to input layer\n"); } else if (!strncmp(val, "ignore", sizeof("ignore") - 1)) { lid_init_state = ACPI_BUTTON_LID_INIT_IGNORE; - pr_info("Do not notify initial lid state\n"); + pr_info("Do not report initial lid state to input layer\n"); } else result = -EINVAL; return result;
