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-rw-r--r--drivers/acpi/Makefile1
-rw-r--r--drivers/acpi/acpi_pnp.c3
-rw-r--r--drivers/acpi/scan.c143
-rw-r--r--drivers/acpi/sleep.c305
-rw-r--r--drivers/acpi/sleep.h16
-rw-r--r--drivers/acpi/x86/s2idle.c460
6 files changed, 598 insertions, 330 deletions
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 44e412506317..076894a3330f 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -54,6 +54,7 @@ acpi-y += property.o
acpi-$(CONFIG_X86) += acpi_cmos_rtc.o
acpi-$(CONFIG_X86) += x86/apple.o
acpi-$(CONFIG_X86) += x86/utils.o
+acpi-$(CONFIG_X86) += x86/s2idle.o
acpi-$(CONFIG_DEBUG_FS) += debugfs.o
acpi-y += acpi_lpat.o
acpi-$(CONFIG_ACPI_LPIT) += acpi_lpit.o
diff --git a/drivers/acpi/acpi_pnp.c b/drivers/acpi/acpi_pnp.c
index 4ed755a963aa..8f2dc176bb41 100644
--- a/drivers/acpi/acpi_pnp.c
+++ b/drivers/acpi/acpi_pnp.c
@@ -319,6 +319,9 @@ static bool matching_id(const char *idstr, const char *list_id)
{
int i;
+ if (strlen(idstr) != strlen(list_id))
+ return false;
+
if (memcmp(idstr, list_id, 3))
return false;
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index a1b226eb2ce2..80b668c80073 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -752,6 +752,7 @@ static bool acpi_info_matches_ids(struct acpi_device_info *info,
/* List of HIDs for which we ignore matching ACPI devices, when checking _DEP lists. */
static const char * const acpi_ignore_dep_ids[] = {
"PNP0D80", /* Windows-compatible System Power Management Controller */
+ "INT33BD", /* Intel Baytrail Mailbox Device */
NULL
};
@@ -1635,8 +1636,6 @@ void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
device_initialize(&device->dev);
dev_set_uevent_suppress(&device->dev, true);
acpi_init_coherency(device);
- /* Assume there are unmet deps until acpi_device_dep_initialize() runs */
- device->dep_unmet = 1;
}
void acpi_device_add_finalize(struct acpi_device *device)
@@ -1842,32 +1841,36 @@ static void acpi_scan_init_hotplug(struct acpi_device *adev)
}
}
-static void acpi_device_dep_initialize(struct acpi_device *adev)
+static u32 acpi_scan_check_dep(acpi_handle handle)
{
- struct acpi_dep_data *dep;
struct acpi_handle_list dep_devices;
acpi_status status;
+ u32 count;
int i;
- adev->dep_unmet = 0;
-
- if (!acpi_has_method(adev->handle, "_DEP"))
- return;
+ /*
+ * Check for _HID here to avoid deferring the enumeration of:
+ * 1. PCI devices.
+ * 2. ACPI nodes describing USB ports.
+ * Still, checking for _HID catches more then just these cases ...
+ */
+ if (!acpi_has_method(handle, "_DEP") || !acpi_has_method(handle, "_HID"))
+ return 0;
- status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
- &dep_devices);
+ status = acpi_evaluate_reference(handle, "_DEP", NULL, &dep_devices);
if (ACPI_FAILURE(status)) {
- dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
- return;
+ acpi_handle_debug(handle, "Failed to evaluate _DEP.\n");
+ return 0;
}
- for (i = 0; i < dep_devices.count; i++) {
+ for (count = 0, i = 0; i < dep_devices.count; i++) {
struct acpi_device_info *info;
- int skip;
+ struct acpi_dep_data *dep;
+ bool skip;
status = acpi_get_object_info(dep_devices.handles[i], &info);
if (ACPI_FAILURE(status)) {
- dev_dbg(&adev->dev, "Error reading _DEP device info\n");
+ acpi_handle_debug(handle, "Error reading _DEP device info\n");
continue;
}
@@ -1877,26 +1880,45 @@ static void acpi_device_dep_initialize(struct acpi_device *adev)
if (skip)
continue;
- dep = kzalloc(sizeof(struct acpi_dep_data), GFP_KERNEL);
+ dep = kzalloc(sizeof(*dep), GFP_KERNEL);
if (!dep)
- return;
+ continue;
+
+ count++;
dep->supplier = dep_devices.handles[i];
- dep->consumer = adev->handle;
- adev->dep_unmet++;
+ dep->consumer = handle;
mutex_lock(&acpi_dep_list_lock);
list_add_tail(&dep->node , &acpi_dep_list);
mutex_unlock(&acpi_dep_list_lock);
}
+
+ return count;
}
-static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
- void *not_used, void **return_value)
+static void acpi_scan_dep_init(struct acpi_device *adev)
+{
+ struct acpi_dep_data *dep;
+
+ mutex_lock(&acpi_dep_list_lock);
+
+ list_for_each_entry(dep, &acpi_dep_list, node) {
+ if (dep->consumer == adev->handle)
+ adev->dep_unmet++;
+ }
+
+ mutex_unlock(&acpi_dep_list_lock);
+}
+
+static bool acpi_bus_scan_second_pass;
+
+static acpi_status acpi_bus_check_add(acpi_handle handle, bool check_dep,
+ struct acpi_device **adev_p)
{
struct acpi_device *device = NULL;
- int type;
unsigned long long sta;
+ int type;
int result;
acpi_bus_get_device(handle, &device);
@@ -1912,20 +1934,42 @@ static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
return AE_OK;
}
+ if (type == ACPI_BUS_TYPE_DEVICE && check_dep) {
+ u32 count = acpi_scan_check_dep(handle);
+ /* Bail out if the number of recorded dependencies is not 0. */
+ if (count > 0) {
+ acpi_bus_scan_second_pass = true;
+ return AE_CTRL_DEPTH;
+ }
+ }
+
acpi_add_single_object(&device, handle, type, sta);
if (!device)
return AE_CTRL_DEPTH;
acpi_scan_init_hotplug(device);
- acpi_device_dep_initialize(device);
+ if (!check_dep)
+ acpi_scan_dep_init(device);
- out:
- if (!*return_value)
- *return_value = device;
+out:
+ if (!*adev_p)
+ *adev_p = device;
return AE_OK;
}
+static acpi_status acpi_bus_check_add_1(acpi_handle handle, u32 lvl_not_used,
+ void *not_used, void **ret_p)
+{
+ return acpi_bus_check_add(handle, true, (struct acpi_device **)ret_p);
+}
+
+static acpi_status acpi_bus_check_add_2(acpi_handle handle, u32 lvl_not_used,
+ void *not_used, void **ret_p)
+{
+ return acpi_bus_check_add(handle, false, (struct acpi_device **)ret_p);
+}
+
static void acpi_default_enumeration(struct acpi_device *device)
{
/*
@@ -1993,12 +2037,16 @@ static int acpi_scan_attach_handler(struct acpi_device *device)
return ret;
}
-static void acpi_bus_attach(struct acpi_device *device)
+static void acpi_bus_attach(struct acpi_device *device, bool first_pass)
{
struct acpi_device *child;
+ bool skip = !first_pass && device->flags.visited;
acpi_handle ejd;
int ret;
+ if (skip)
+ goto ok;
+
if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
register_dock_dependent_device(device, ejd);
@@ -2045,9 +2093,9 @@ static void acpi_bus_attach(struct acpi_device *device)
ok:
list_for_each_entry(child, &device->children, node)
- acpi_bus_attach(child);
+ acpi_bus_attach(child, first_pass);
- if (device->handler && device->handler->hotplug.notify_online)
+ if (!skip && device->handler && device->handler->hotplug.notify_online)
device->handler->hotplug.notify_online(device);
}
@@ -2065,7 +2113,8 @@ void acpi_walk_dep_device_list(acpi_handle handle)
adev->dep_unmet--;
if (!adev->dep_unmet)
- acpi_bus_attach(adev);
+ acpi_bus_attach(adev, true);
+
list_del(&dep->node);
kfree(dep);
}
@@ -2090,17 +2139,37 @@ EXPORT_SYMBOL_GPL(acpi_walk_dep_device_list);
*/
int acpi_bus_scan(acpi_handle handle)
{
- void *device = NULL;
+ struct acpi_device *device = NULL;
+
+ acpi_bus_scan_second_pass = false;
- if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
+ /* Pass 1: Avoid enumerating devices with missing dependencies. */
+
+ if (ACPI_SUCCESS(acpi_bus_check_add(handle, true, &device)))
acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
- acpi_bus_check_add, NULL, NULL, &device);
+ acpi_bus_check_add_1, NULL, NULL,
+ (void **)&device);
+
+ if (!device)
+ return -ENODEV;
- if (device) {
- acpi_bus_attach(device);
+ acpi_bus_attach(device, true);
+
+ if (!acpi_bus_scan_second_pass)
return 0;
- }
- return -ENODEV;
+
+ /* Pass 2: Enumerate all of the remaining devices. */
+
+ device = NULL;
+
+ if (ACPI_SUCCESS(acpi_bus_check_add(handle, false, &device)))
+ acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
+ acpi_bus_check_add_2, NULL, NULL,
+ (void **)&device);
+
+ acpi_bus_attach(device, false);
+
+ return 0;
}
EXPORT_SYMBOL(acpi_bus_scan);
diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c
index aff13bf4d947..09fd13757b65 100644
--- a/drivers/acpi/sleep.c
+++ b/drivers/acpi/sleep.c
@@ -92,10 +92,6 @@ bool acpi_sleep_state_supported(u8 sleep_state)
}
#ifdef CONFIG_ACPI_SLEEP
-static bool sleep_no_lps0 __read_mostly;
-module_param(sleep_no_lps0, bool, 0644);
-MODULE_PARM_DESC(sleep_no_lps0, "Do not use the special LPS0 device interface");
-
static u32 acpi_target_sleep_state = ACPI_STATE_S0;
u32 acpi_target_system_state(void)
@@ -165,7 +161,7 @@ static int __init init_nvs_nosave(const struct dmi_system_id *d)
return 0;
}
-static bool acpi_sleep_default_s3;
+bool acpi_sleep_default_s3;
static int __init init_default_s3(const struct dmi_system_id *d)
{
@@ -688,268 +684,13 @@ static const struct platform_suspend_ops acpi_suspend_ops_old = {
static bool s2idle_wakeup;
-/*
- * On platforms supporting the Low Power S0 Idle interface there is an ACPI
- * device object with the PNP0D80 compatible device ID (System Power Management
- * Controller) and a specific _DSM method under it. That method, if present,
- * can be used to indicate to the platform that the OS is transitioning into a
- * low-power state in which certain types of activity are not desirable or that
- * it is leaving such a state, which allows the platform to adjust its operation
- * mode accordingly.
- */
-static const struct acpi_device_id lps0_device_ids[] = {
- {"PNP0D80", },
- {"", },
-};
-
-#define ACPI_LPS0_DSM_UUID "c4eb40a0-6cd2-11e2-bcfd-0800200c9a66"
-
-#define ACPI_LPS0_GET_DEVICE_CONSTRAINTS 1
-#define ACPI_LPS0_SCREEN_OFF 3
-#define ACPI_LPS0_SCREEN_ON 4
-#define ACPI_LPS0_ENTRY 5
-#define ACPI_LPS0_EXIT 6
-
-static acpi_handle lps0_device_handle;
-static guid_t lps0_dsm_guid;
-static char lps0_dsm_func_mask;
-
-/* Device constraint entry structure */
-struct lpi_device_info {
- char *name;
- int enabled;
- union acpi_object *package;
-};
-
-/* Constraint package structure */
-struct lpi_device_constraint {
- int uid;
- int min_dstate;
- int function_states;
-};
-
-struct lpi_constraints {
- acpi_handle handle;
- int min_dstate;
-};
-
-static struct lpi_constraints *lpi_constraints_table;
-static int lpi_constraints_table_size;
-
-static void lpi_device_get_constraints(void)
-{
- union acpi_object *out_obj;
- int i;
-
- out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid,
- 1, ACPI_LPS0_GET_DEVICE_CONSTRAINTS,
- NULL, ACPI_TYPE_PACKAGE);
-
- acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n",
- out_obj ? "successful" : "failed");
-
- if (!out_obj)
- return;
-
- lpi_constraints_table = kcalloc(out_obj->package.count,
- sizeof(*lpi_constraints_table),
- GFP_KERNEL);
- if (!lpi_constraints_table)
- goto free_acpi_buffer;
-
- acpi_handle_debug(lps0_device_handle, "LPI: constraints list begin:\n");
-
- for (i = 0; i < out_obj->package.count; i++) {
- struct lpi_constraints *constraint;
- acpi_status status;
- union acpi_object *package = &out_obj->package.elements[i];
- struct lpi_device_info info = { };
- int package_count = 0, j;
-
- if (!package)
- continue;
-
- for (j = 0; j < package->package.count; ++j) {
- union acpi_object *element =
- &(package->package.elements[j]);
-
- switch (element->type) {
- case ACPI_TYPE_INTEGER:
- info.enabled = element->integer.value;
- break;
- case ACPI_TYPE_STRING:
- info.name = element->string.pointer;
- break;
- case ACPI_TYPE_PACKAGE:
- package_count = element->package.count;
- info.package = element->package.elements;
- break;
- }
- }
-
- if (!info.enabled || !info.package || !info.name)
- continue;
-
- constraint = &lpi_constraints_table[lpi_constraints_table_size];
-
- status = acpi_get_handle(NULL, info.name, &constraint->handle);
- if (ACPI_FAILURE(status))
- continue;
-
- acpi_handle_debug(lps0_device_handle,
- "index:%d Name:%s\n", i, info.name);
-
- constraint->min_dstate = -1;
-
- for (j = 0; j < package_count; ++j) {
- union acpi_object *info_obj = &info.package[j];
- union acpi_object *cnstr_pkg;
- union acpi_object *obj;
- struct lpi_device_constraint dev_info;
-
- switch (info_obj->type) {
- case ACPI_TYPE_INTEGER:
- /* version */
- break;
- case ACPI_TYPE_PACKAGE:
- if (info_obj->package.count < 2)
- break;
-
- cnstr_pkg = info_obj->package.elements;
- obj = &cnstr_pkg[0];
- dev_info.uid = obj->integer.value;
- obj = &cnstr_pkg[1];
- dev_info.min_dstate = obj->integer.value;
-
- acpi_handle_debug(lps0_device_handle,
- "uid:%d min_dstate:%s\n",
- dev_info.uid,
- acpi_power_state_string(dev_info.min_dstate));
-
- constraint->min_dstate = dev_info.min_dstate;
- break;
- }
- }
-
- if (constraint->min_dstate < 0) {
- acpi_handle_debug(lps0_device_handle,
- "Incomplete constraint defined\n");
- continue;
- }
-
- lpi_constraints_table_size++;
- }
-
- acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n");
-
-free_acpi_buffer:
- ACPI_FREE(out_obj);
-}
-
-static void lpi_check_constraints(void)
-{
- int i;
-
- for (i = 0; i < lpi_constraints_table_size; ++i) {
- acpi_handle handle = lpi_constraints_table[i].handle;
- struct acpi_device *adev;
-
- if (!handle || acpi_bus_get_device(handle, &adev))
- continue;
-
- acpi_handle_debug(handle,
- "LPI: required min power state:%s current power state:%s\n",
- acpi_power_state_string(lpi_constraints_table[i].min_dstate),
- acpi_power_state_string(adev->power.state));
-
- if (!adev->flags.power_manageable) {
- acpi_handle_info(handle, "LPI: Device not power manageable\n");
- lpi_constraints_table[i].handle = NULL;
- continue;
- }
-
- if (adev->power.state < lpi_constraints_table[i].min_dstate)
- acpi_handle_info(handle,
- "LPI: Constraint not met; min power state:%s current power state:%s\n",
- acpi_power_state_string(lpi_constraints_table[i].min_dstate),
- acpi_power_state_string(adev->power.state));
- }
-}
-
-static void acpi_sleep_run_lps0_dsm(unsigned int func)
-{
- union acpi_object *out_obj;
-
- if (!(lps0_dsm_func_mask & (1 << func)))
- return;
-
- out_obj = acpi_evaluate_dsm(lps0_device_handle, &lps0_dsm_guid, 1, func, NULL);
- ACPI_FREE(out_obj);
-
- acpi_handle_debug(lps0_device_handle, "_DSM function %u evaluation %s\n",
- func, out_obj ? "successful" : "failed");
-}
-
-static int lps0_device_attach(struct acpi_device *adev,
- const struct acpi_device_id *not_used)
-{
- union acpi_object *out_obj;
-
- if (lps0_device_handle)
- return 0;
-
- if (!(acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0))
- return 0;
-
- guid_parse(ACPI_LPS0_DSM_UUID, &lps0_dsm_guid);
- /* Check if the _DSM is present and as expected. */
- out_obj = acpi_evaluate_dsm(adev->handle, &lps0_dsm_guid, 1, 0, NULL);
- if (!out_obj || out_obj->type != ACPI_TYPE_BUFFER) {
- acpi_handle_debug(adev->handle,
- "_DSM function 0 evaluation failed\n");
- return 0;
- }
-
- lps0_dsm_func_mask = *(char *)out_obj->buffer.pointer;
-
- ACPI_FREE(out_obj);
-
- acpi_handle_debug(adev->handle, "_DSM function mask: 0x%x\n",
- lps0_dsm_func_mask);
-
- lps0_device_handle = adev->handle;
-
- lpi_device_get_constraints();
-
- /*
- * Use suspend-to-idle by default if the default suspend mode was not
- * set from the command line.
- */
- if (mem_sleep_default > PM_SUSPEND_MEM && !acpi_sleep_default_s3)
- mem_sleep_current = PM_SUSPEND_TO_IDLE;
-
- /*
- * Some LPS0 systems, like ASUS Zenbook UX430UNR/i7-8550U, require the
- * EC GPE to be enabled while suspended for certain wakeup devices to
- * work, so mark it as wakeup-capable.
- */
- acpi_ec_mark_gpe_for_wake();
-
- return 0;
-}
-
-static struct acpi_scan_handler lps0_handler = {
- .ids = lps0_device_ids,
- .attach = lps0_device_attach,
-};
-
-static int acpi_s2idle_begin(void)
+int acpi_s2idle_begin(void)
{
acpi_scan_lock_acquire();
return 0;
}
-static int acpi_s2idle_prepare(void)
+int acpi_s2idle_prepare(void)
{
if (acpi_sci_irq_valid()) {
enable_irq_wake(acpi_sci_irq);
@@ -966,21 +707,7 @@ static int acpi_s2idle_prepare(void)
return 0;
}
-static int acpi_s2idle_prepare_late(void)
-{
- if (!lps0_device_handle || sleep_no_lps0)
- return 0;
-
- if (pm_debug_messages_on)
- lpi_check_constraints();
-
- acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_OFF);
- acpi_sleep_run_lps0_dsm(ACPI_LPS0_ENTRY);
-
- return 0;
-}
-
-static bool acpi_s2idle_wake(void)
+bool acpi_s2idle_wake(void)
{
if (!acpi_sci_irq_valid())
return pm_wakeup_pending();
@@ -1046,16 +773,7 @@ static bool acpi_s2idle_wake(void)
return false;
}
-static void acpi_s2idle_restore_early(void)
-{
- if (!lps0_device_handle || sleep_no_lps0)
- return;
-
- acpi_sleep_run_lps0_dsm(ACPI_LPS0_EXIT);
- acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_ON);
-}
-
-static void acpi_s2idle_restore(void)
+void acpi_s2idle_restore(void)
{
/*
* Drain pending events before restoring the working-state configuration
@@ -1077,7 +795,7 @@ static void acpi_s2idle_restore(void)
}
}
-static void acpi_s2idle_end(void)
+void acpi_s2idle_end(void)
{
acpi_scan_lock_release();
}
@@ -1085,13 +803,16 @@ static void acpi_s2idle_end(void)
static const struct platform_s2idle_ops acpi_s2idle_ops = {
.begin = acpi_s2idle_begin,
.prepare = acpi_s2idle_prepare,
- .prepare_late = acpi_s2idle_prepare_late,
.wake = acpi_s2idle_wake,
- .restore_early = acpi_s2idle_restore_early,
.restore = acpi_s2idle_restore,
.end = acpi_s2idle_end,
};
+void __weak acpi_s2idle_setup(void)
+{
+ s2idle_set_ops(&acpi_s2idle_ops);
+}
+
static void acpi_sleep_suspend_setup(void)
{
int i;
@@ -1103,13 +824,11 @@ static void acpi_sleep_suspend_setup(void)
suspend_set_ops(old_suspend_ordering ?
&acpi_suspend_ops_old : &acpi_suspend_ops);
- acpi_scan_add_handler(&lps0_handler);
- s2idle_set_ops(&acpi_s2idle_ops);
+ acpi_s2idle_setup();
}
#else /* !CONFIG_SUSPEND */
#define s2idle_wakeup (false)
-#define lps0_device_handle (NULL)
static inline void acpi_sleep_suspend_setup(void) {}
#endif /* !CONFIG_SUSPEND */
diff --git a/drivers/acpi/sleep.h b/drivers/acpi/sleep.h
index 3d90480ce1b1..1856f76ac83f 100644
--- a/drivers/acpi/sleep.h
+++ b/drivers/acpi/sleep.h
@@ -15,3 +15,19 @@ static inline acpi_status acpi_set_waking_vector(u32 wakeup_address)
return acpi_set_firmware_waking_vector(
(acpi_physical_address)wakeup_address, 0);
}
+
+extern int acpi_s2idle_begin(void);
+extern int acpi_s2idle_prepare(void);
+extern int acpi_s2idle_prepare_late(void);
+extern bool acpi_s2idle_wake(void);
+extern void acpi_s2idle_restore_early(void);
+extern void acpi_s2idle_restore(void);
+extern void acpi_s2idle_end(void);
+
+extern void acpi_s2idle_setup(void);
+
+#ifdef CONFIG_ACPI_SLEEP
+extern bool acpi_sleep_default_s3;
+#else
+#define acpi_sleep_default_s3 (1)
+#endif
diff --git a/drivers/acpi/x86/s2idle.c b/drivers/acpi/x86/s2idle.c
new file mode 100644
index 000000000000..25fea34b544c
--- /dev/null
+++ b/drivers/acpi/x86/s2idle.c
@@ -0,0 +1,460 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Architecture-specific ACPI-based support for suspend-to-idle.
+ *
+ * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ * Author: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
+ * Author: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
+ *
+ * On platforms supporting the Low Power S0 Idle interface there is an ACPI
+ * device object with the PNP0D80 compatible device ID (System Power Management
+ * Controller) and a specific _DSM method under it. That method, if present,
+ * can be used to indicate to the platform that the OS is transitioning into a
+ * low-power state in which certain types of activity are not desirable or that
+ * it is leaving such a state, which allows the platform to adjust its operation
+ * mode accordingly.
+ */
+
+#include <linux/acpi.h>
+#include <linux/device.h>
+#include <linux/suspend.h>
+
+#include "../sleep.h"
+
+#ifdef CONFIG_SUSPEND
+
+static bool sleep_no_lps0 __read_mostly;
+module_param(sleep_no_lps0, bool, 0644);
+MODULE_PARM_DESC(sleep_no_lps0, "Do not use the special LPS0 device interface");
+
+static const struct acpi_device_id lps0_device_ids[] = {
+ {"PNP0D80", },
+ {"", },
+};
+
+#define ACPI_LPS0_DSM_UUID "c4eb40a0-6cd2-11e2-bcfd-0800200c9a66"
+
+#define ACPI_LPS0_GET_DEVICE_CONSTRAINTS 1
+#define ACPI_LPS0_SCREEN_OFF 3
+#define ACPI_LPS0_SCREEN_ON 4
+#define ACPI_LPS0_ENTRY 5
+#define ACPI_LPS0_EXIT 6
+
+/* AMD */
+#define ACPI_LPS0_DSM_UUID_AMD "e3f32452-febc-43ce-9039-932122d37721"
+#define ACPI_LPS0_SCREEN_OFF_AMD 4
+#define ACPI_LPS0_SCREEN_ON_AMD 5
+
+static acpi_handle lps0_device_handle;
+static guid_t lps0_dsm_guid;
+static char lps0_dsm_func_mask;
+
+/* Device constraint entry structure */
+struct lpi_device_info {
+ char *name;
+ int enabled;
+ union acpi_object *package;
+};
+
+/* Constraint package structure */
+struct lpi_device_constraint {
+ int uid;
+ int min_dstate;
+ int function_states;
+};
+
+struct lpi_constraints {
+ acpi_handle handle;
+ int min_dstate;
+};
+
+/* AMD */
+/* Device constraint entry structure */
+struct lpi_device_info_amd {
+ int revision;
+ int count;
+ union acpi_object *package;
+};
+
+/* Constraint package structure */
+struct lpi_device_constraint_amd {
+ char *name;
+ int enabled;
+ int function_states;
+ int min_dstate;
+};
+
+static struct lpi_constraints *lpi_constraints_table;
+static int lpi_constraints_table_size;
+static int rev_id;
+
+static void lpi_device_get_constraints_amd(void)
+{
+ union acpi_object *out_obj;
+ int i, j, k;
+
+ out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid,
+ 1, ACPI_LPS0_GET_DEVICE_CONSTRAINTS,
+ NULL, ACPI_TYPE_PACKAGE);
+
+ if (!out_obj)
+ return;
+
+ acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n",
+ out_obj ? "successful" : "failed");
+
+ for (i = 0; i < out_obj->package.count; i++) {
+ union acpi_object *package = &out_obj->package.elements[i];
+ struct lpi_device_info_amd info = { };
+
+ if (package->type == ACPI_TYPE_INTEGER) {
+ switch (i) {
+ case 0:
+ info.revision = package->integer.value;
+ break;
+ case 1:
+ info.count = package->integer.value;
+ break;
+ }
+ } else if (package->type == ACPI_TYPE_PACKAGE) {
+ lpi_constraints_table = kcalloc(package->package.count,
+ sizeof(*lpi_constraints_table),
+ GFP_KERNEL);
+
+ if (!lpi_constraints_table)
+ goto free_acpi_buffer;
+
+ acpi_handle_debug(lps0_device_handle,
+ "LPI: constraints list begin:\n");
+
+ for (j = 0; j < package->package.count; ++j) {
+ union acpi_object *info_obj = &package->package.elements[j];
+ struct lpi_device_constraint_amd dev_info = {};
+ struct lpi_constraints *list;
+ acpi_status status;
+
+ for (k = 0; k < info_obj->package.count; ++k) {
+ union acpi_object *obj = &info_obj->package.elements[k];
+ union acpi_object *obj_new;
+
+ list = &lpi_constraints_table[lpi_constraints_table_size];
+ list->min_dstate = -1;
+
+ obj_new = &obj[k];
+ switch (k) {
+ case 0:
+ dev_info.enabled = obj->integer.value;
+ break;
+ case 1:
+ dev_info.name = obj->string.pointer;
+ break;
+ case 2:
+ dev_info.function_states = obj->integer.value;
+ break;
+ case 3:
+ dev_info.min_dstate = obj->integer.value;
+ break;
+ }
+
+ if (!dev_info.enabled || !dev_info.name ||
+ !dev_info.min_dstate)
+ continue;
+
+ status = acpi_get_handle(NULL, dev_info.name,
+ &list->handle);
+ if (ACPI_FAILURE(status))
+ continue;
+
+ acpi_handle_debug(lps0_device_handle,
+ "Name:%s\n", dev_info.name);
+
+ list->min_dstate = dev_info.min_dstate;
+
+ if (list->min_dstate < 0) {
+ acpi_handle_debug(lps0_device_handle,
+ "Incomplete constraint defined\n");
+ continue;
+ }
+ }
+ lpi_constraints_table_size++;
+ }
+ }
+ }
+
+ acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n");
+
+free_acpi_buffer:
+ ACPI_FREE(out_obj);
+}
+
+static void lpi_device_get_constraints(void)
+{
+ union acpi_object *out_obj;
+ int i;
+
+ out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid,
+ 1, ACPI_LPS0_GET_DEVICE_CONSTRAINTS,
+ NULL, ACPI_TYPE_PACKAGE);
+
+ acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n",
+ out_obj ? "successful" : "failed");
+
+ if (!out_obj)
+ return;
+
+ lpi_constraints_table = kcalloc(out_obj->package.count,
+ sizeof(*lpi_constraints_table),
+ GFP_KERNEL);
+ if (!lpi_constraints_table)
+ goto free_acpi_buffer;
+
+ acpi_handle_debug(lps0_device_handle, "LPI: constraints list begin:\n");
+
+ for (i = 0; i < out_obj->package.count; i++) {
+ struct lpi_constraints *constraint;
+ acpi_status status;
+ union acpi_object *package = &out_obj->package.elements[i];
+ struct lpi_device_info info = { };
+ int package_count = 0, j;
+
+ if (!package)
+ continue;
+
+ for (j = 0; j < package->package.count; ++j) {
+ union acpi_object *element =
+ &(package->package.elements[j]);
+
+ switch (element->type) {
+ case ACPI_TYPE_INTEGER:
+ info.enabled = element->integer.value;
+ break;
+ case ACPI_TYPE_STRING:
+ info.name = element->string.pointer;
+ break;
+ case ACPI_TYPE_PACKAGE:
+ package_count = element->package.count;
+ info.package = element->package.elements;
+ break;
+ }
+ }
+
+ if (!info.enabled || !info.package || !info.name)
+ continue;
+
+ constraint = &lpi_constraints_table[lpi_constraints_table_size];
+
+ status = acpi_get_handle(NULL, info.name, &constraint->handle);
+ if (ACPI_FAILURE(status))
+ continue;
+
+ acpi_handle_debug(lps0_device_handle,
+ "index:%d Name:%s\n", i, info.name);
+
+ constraint->min_dstate = -1;
+
+ for (j = 0; j < package_count; ++j) {
+ union acpi_object *info_obj = &info.package[j];
+ union acpi_object *cnstr_pkg;
+ union acpi_object *obj;
+ struct lpi_device_constraint dev_info;
+
+ switch (info_obj->type) {
+ case ACPI_TYPE_INTEGER:
+ /* version */
+ break;
+ case ACPI_TYPE_PACKAGE:
+ if (info_obj->package.count < 2)
+ break;
+
+ cnstr_pkg = info_obj->package.elements;
+ obj = &cnstr_pkg[0];
+ dev_info.uid = obj->integer.value;
+ obj = &cnstr_pkg[1];
+ dev_info.min_dstate = obj->integer.value;
+
+ acpi_handle_debug(lps0_device_handle,
+ "uid:%d min_dstate:%s\n",
+ dev_info.uid,
+ acpi_power_state_string(dev_info.min_dstate));
+
+ constraint->min_dstate = dev_info.min_dstate;
+ break;
+ }
+ }
+
+ if (constraint->min_dstate < 0) {
+ acpi_handle_debug(lps0_device_handle,
+ "Incomplete constraint defined\n");
+ continue;
+ }
+
+ lpi_constraints_table_size++;
+ }
+
+ acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n");
+
+free_acpi_buffer:
+ ACPI_FREE(out_obj);
+}
+
+static void lpi_check_constraints(void)
+{
+ int i;
+
+ for (i = 0; i < lpi_constraints_table_size; ++i) {
+ acpi_handle handle = lpi_constraints_table[i].handle;
+ struct acpi_device *adev;
+
+ if (!handle || acpi_bus_get_device(handle, &adev))
+ continue;
+
+ acpi_handle_debug(handle,
+ "LPI: required min power state:%s current power state:%s\n",
+ acpi_power_state_string(lpi_constraints_table[i].min_dstate),
+ acpi_power_state_string(adev->power.state));
+
+ if (!adev->flags.power_manageable) {
+ acpi_handle_info(handle, "LPI: Device not power manageable\n");
+ lpi_constraints_table[i].handle = NULL;
+ continue;
+ }
+
+ if (adev->power.state < lpi_constraints_table[i].min_dstate)
+ acpi_handle_info(handle,
+ "LPI: Constraint not met; min power state:%s current power state:%s\n",
+ acpi_power_state_string(lpi_constraints_table[i].min_dstate),
+ acpi_power_state_string(adev->power.state));
+ }
+}
+
+static void acpi_sleep_run_lps0_dsm(unsigned int func)
+{
+ union acpi_object *out_obj;
+
+ if (!(lps0_dsm_func_mask & (1 << func)))
+ return;
+
+ out_obj = acpi_evaluate_dsm(lps0_device_handle, &lps0_dsm_guid, rev_id, func, NULL);
+ ACPI_FREE(out_obj);
+
+ acpi_handle_debug(lps0_device_handle, "_DSM function %u evaluation %s\n",
+ func, out_obj ? "successful" : "failed");
+}
+
+static bool acpi_s2idle_vendor_amd(void)
+{
+ return boot_cpu_data.x86_vendor == X86_VENDOR_AMD;
+}
+
+static int lps0_device_attach(struct acpi_device *adev,
+ const struct acpi_device_id *not_used)
+{
+ union acpi_object *out_obj;
+
+ if (lps0_device_handle)
+ return 0;
+
+ if (!(acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0))
+ return 0;
+
+ if (acpi_s2idle_vendor_amd()) {
+ guid_parse(ACPI_LPS0_DSM_UUID_AMD, &lps0_dsm_guid);
+ out_obj = acpi_evaluate_dsm(adev->handle, &lps0_dsm_guid, 0, 0, NULL);
+ rev_id = 0;
+ } else {
+ guid_parse(ACPI_LPS0_DSM_UUID, &lps0_dsm_guid);
+ out_obj = acpi_evaluate_dsm(adev->handle, &lps0_dsm_guid, 1, 0, NULL);
+ rev_id = 1;
+ }
+
+ /* Check if the _DSM is present and as expected. */
+ if (!out_obj || out_obj->type != ACPI_TYPE_BUFFER) {
+ acpi_handle_debug(adev->handle,
+ "_DSM function 0 evaluation failed\n");
+ return 0;
+ }
+
+ lps0_dsm_func_mask = *(char *)out_obj->buffer.pointer;
+
+ ACPI_FREE(out_obj);
+
+ acpi_handle_debug(adev->handle, "_DSM function mask: 0x%x\n",
+ lps0_dsm_func_mask);
+
+ lps0_device_handle = adev->handle;
+
+ if (acpi_s2idle_vendor_amd())
+ lpi_device_get_constraints_amd();
+ else
+ lpi_device_get_constraints();
+
+ /*
+ * Use suspend-to-idle by default if the default suspend mode was not
+ * set from the command line.
+ */
+ if (mem_sleep_default > PM_SUSPEND_MEM && !acpi_sleep_default_s3)
+ mem_sleep_current = PM_SUSPEND_TO_IDLE;
+
+ /*
+ * Some LPS0 systems, like ASUS Zenbook UX430UNR/i7-8550U, require the
+ * EC GPE to be enabled while suspended for certain wakeup devices to
+ * work, so mark it as wakeup-capable.
+ */
+ acpi_ec_mark_gpe_for_wake();
+
+ return 0;
+}
+
+static struct acpi_scan_handler lps0_handler = {
+ .ids = lps0_device_ids,
+ .attach = lps0_device_attach,
+};
+
+int acpi_s2idle_prepare_late(void)
+{
+ if (!lps0_device_handle || sleep_no_lps0)
+ return 0;
+
+ if (pm_debug_messages_on)
+ lpi_check_constraints();
+
+ if (acpi_s2idle_vendor_amd()) {
+ acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_OFF_AMD);
+ } else {
+ acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_OFF);
+ acpi_sleep_run_lps0_dsm(ACPI_LPS0_ENTRY);
+ }
+
+ return 0;
+}
+
+void acpi_s2idle_restore_early(void)
+{
+ if (!lps0_device_handle || sleep_no_lps0)
+ return;
+
+ if (acpi_s2idle_vendor_amd()) {
+ acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_ON_AMD);
+ } else {
+ acpi_sleep_run_lps0_dsm(ACPI_LPS0_EXIT);
+ acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_ON);
+ }
+}
+
+static const struct platform_s2idle_ops acpi_s2idle_ops_lps0 = {
+ .begin = acpi_s2idle_begin,
+ .prepare = acpi_s2idle_prepare,
+ .prepare_late = acpi_s2idle_prepare_late,
+ .wake = acpi_s2idle_wake,
+ .restore_early = acpi_s2idle_restore_early,
+ .restore = acpi_s2idle_restore,
+ .end = acpi_s2idle_end,
+};
+
+void acpi_s2idle_setup(void)
+{
+ acpi_scan_add_handler(&lps0_handler);
+ s2idle_set_ops(&acpi_s2idle_ops_lps0);
+}
+
+#endif /* CONFIG_SUSPEND */