diff options
| -rw-r--r-- | Documentation/acpi/acpi-lid.txt | 16 | ||||
| -rw-r--r-- | drivers/acpi/button.c | 9 |
2 files changed, 21 insertions, 4 deletions
diff --git a/Documentation/acpi/acpi-lid.txt b/Documentation/acpi/acpi-lid.txt index 22cb3091f297..effe7af3a5af 100644 --- a/Documentation/acpi/acpi-lid.txt +++ b/Documentation/acpi/acpi-lid.txt @@ -59,20 +59,28 @@ button driver uses the following 3 modes in order not to trigger issues. If the userspace hasn't been prepared to ignore the unreliable "opened" events and the unreliable initial state notification, Linux users can use the following kernel parameters to handle the possible issues: -A. button.lid_init_state=open: +A. button.lid_init_state=method: + When this option is specified, the ACPI button driver reports the + initial lid state using the returning value of the _LID control method + and whether the "opened"/"closed" events are paired fully relies on the + firmware implementation. + This option can be used to fix some platforms where the returning value + of the _LID control method is reliable but the initial lid state + notification is missing. + This option is the default behavior during the period the userspace + isn't ready to handle the buggy AML tables. +B. button.lid_init_state=open: When this option is specified, the ACPI button driver always reports the initial lid state as "opened" and whether the "opened"/"closed" events are paired fully relies on the firmware implementation. This may fix some platforms where the returning value of the _LID control method is not reliable and the initial lid state notification is missing. - This option is the default behavior during the period the userspace - isn't ready to handle the buggy AML tables. If the userspace has been prepared to ignore the unreliable "opened" events and the unreliable initial state notification, Linux users should always use the following kernel parameter: -B. button.lid_init_state=ignore: +C. button.lid_init_state=ignore: When this option is specified, the ACPI button driver never reports the initial lid state and there is a compensation mechanism implemented to ensure that the reliable "closed" notifications can always be delievered diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c index 668137e4a069..6d5a8c1d3132 100644 --- a/drivers/acpi/button.c +++ b/drivers/acpi/button.c @@ -57,6 +57,7 @@ #define ACPI_BUTTON_LID_INIT_IGNORE 0x00 #define ACPI_BUTTON_LID_INIT_OPEN 0x01 +#define ACPI_BUTTON_LID_INIT_METHOD 0x02 #define _COMPONENT ACPI_BUTTON_COMPONENT ACPI_MODULE_NAME("button"); @@ -376,6 +377,9 @@ static void acpi_lid_initialize_state(struct acpi_device *device) case ACPI_BUTTON_LID_INIT_OPEN: (void)acpi_lid_notify_state(device, 1); break; + case ACPI_BUTTON_LID_INIT_METHOD: + (void)acpi_lid_update_state(device); + break; case ACPI_BUTTON_LID_INIT_IGNORE: default: break; @@ -559,6 +563,9 @@ static int param_set_lid_init_state(const char *val, struct kernel_param *kp) if (!strncmp(val, "open", sizeof("open") - 1)) { lid_init_state = ACPI_BUTTON_LID_INIT_OPEN; pr_info("Notify initial lid state as open\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"); } 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"); @@ -572,6 +579,8 @@ static int param_get_lid_init_state(char *buffer, struct kernel_param *kp) switch (lid_init_state) { case ACPI_BUTTON_LID_INIT_OPEN: return sprintf(buffer, "open"); + case ACPI_BUTTON_LID_INIT_METHOD: + return sprintf(buffer, "method"); case ACPI_BUTTON_LID_INIT_IGNORE: return sprintf(buffer, "ignore"); default: |