Merge series "Extend regulator notification support" from Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>:

Extend regulator notification support

This series extends the regulator notification and error flag support.
Initial discussion on the topic can be found here:
https://lore.kernel.org/lkml/6046836e22b8252983f08d5621c35ececb97820d.camel@fi.rohmeurope.com/

In a nutshell - the series adds:

1. WARNING level events/error flags. (Patch 3)
  Current regulator 'ERROR' event notifications for over/under
  voltage, over current and over temperature are used to indicate
  condition where monitored entity is so badly "off" that it actually
  indicates a hardware error which can not be recovered. The most
  typical hanling for that is believed to be a (graceful)
  system-shutdown. Here we add set of 'WARNING' level flags to allow
  sending notifications to consumers before things are 'that badly off'
  so that consumer drivers can implement recovery-actions.
2. Device-tree properties for specifying limit values. (Patches 1, 5)
  Add limits for above mentioned 'ERROR' and 'WARNING' levels (which
  send notifications to consumers) and also for a 'PROTECTION' level
  (which will be used to immediately shut-down the regulator(s) W/O
  informing consumer drivers. Typically implemented by hardware).
  Property parsing is implemented in regulator core which then calls
  callback operations for limit setting from the IC drivers. A
  warning is emitted if protection is requested by device tree but the
  underlying IC does not support configuring requested protection.
3. Helpers which can be registered by IC. (Patch 4)
  Target is to avoid implementing IRQ handling and IRQ storm protection
  in each IC driver. (Many of the ICs implementin these IRQs do not allow
  masking or acking the IRQ but keep the IRQ asserted for the whole
  duration of problem keeping the processor in IRQ handling loop).
4. Emergency poweroff function (refactored out of the thermal_core to
  kernel/reboot.c) which is called if IC fires error IRQs but IC reading
  fails and given retry-count is exceeded. (Patches 2, 4)
  Please note that the mutex in the emergency shutdown was replaced by a
  simple atomic in order to allow call from any context.

The helper was attempted to be done so it could be used to implement
roughly same logic as is used in qcom-labibb regulator. This means
amongst other things a safety shut-down if IC registers are not readable.
Using these shut-down retry counters are optional. The idea is that the
helper could be also used by simpler ICs which do not provide status
register(s) which can be used to check if error is still active.

ICs which do not have such status register can simply omit the 'renable'
callback (and retry-counts etc) - and helper assumes the situation is Ok
and re-enables IRQ after given time period. If problem persists the
handler is ran again and another notification is sent - but at least the
delay allows processor to avoid IRQ loop.

Patch 7 takes this notification support in use at BD9576MUF.
Patch 8 is related to MFD change which is not really related to the RFC
here. It was added to this series in order to avoid potential conflicts.
Patch 9 adds a maintainers entry.

Changelog v10-RESEND:
   - rebased on v5.13-rc4
Changelog v10:
   - rebased on v5.13-rc2
   - Move rdev_*() print macros to the internal.h and use rdev_dbg()
     from irq_helpers.c
   - Export rdev_get_name() and move it from coupler.h to driver.h for
     others to use. (It was already in coupler.h but not exported -
     usage was limited and coupler.h does not sound like optimal place
     as rdev_name is not only used by coupled regulators)
   - Send all regulator notifications from irq_helpers.c at one OR'd
     event for the sake of simplicity. For BD9576 this does not matter
     as it has own IRQ for each event case. Header defining events says
     they may be OR'd.
   - Change WARN() at protection shutdown to pr_emerg as suggested by
     Petr.
Changelog v9:
   - rebases on v5.13-rc1
   - Update thermal documentation
   - Fix regulator notification event number
Changelog v8:
   - split shutdown API adding and thermal core taking it in use to
     own patches.
   - replace the spinlock with atomic when ensuring the emergency
     shutdown is only called once.
Changelog v7:
  general:
   - rebased on v5.12-rc7
   - new patch for refactoring the hw-failure reboot logic out of
     thermal_core.c for others to use.
  notification helpers:
   - fix regulator error_flags query
   - grammar/typos
   - do not BUG() but attempt to shut-down the system
   - use BITS_PER_TYPE()

Changelog v6:
  Add MAINTAINERS entry
  Changes to IRQ notifiers
   - move devm functions to drivers/regulator/devres.c
   - drop irq validity check
   - use devm_add_action_or_reset()
   - fix styling issues
   - fix kerneldocs

Changelog v5:
   - Fix the badly formatted pr_emerg() call.

Changelog v4:
   - rebased on v5.12-rc6
   - dropped RFC
   - fix external FET DT-binding.
   - improve prints for cases when expecting HW failure.
   - styling and typos

Changelog v3:
  Regulator core:
   - Fix dangling pointer access at regulator_irq_helper()
  stpmic1_regulator:
   - fix function prototype (compile error)
  bd9576-regulator:
   - Update over current limits to what was given in new data-sheet
     (REV00K)
   - Allow over-current monitoring without external FET. Set limits to
     values given in data-sheet (REV00K).

Changelog v2:
  Generic:
  - rebase on v5.12-rc2 + BD9576 series
  - Split devm variant of delayed wq to own series
  Regulator framework:
  - Provide non devm variant of IRQ notification helpers
  - shorten dt-property names as suggested by Rob
  - unconditionally call map_event in IRQ handling and require it to be
    populated
  BD9576 regulators:
  - change the FET resistance property to micro-ohms
  - fix voltage computation in OC limit setting

8 files changed, 66 insertions, 21 deletions

diff --git a/drivers/acpi/acpi_apd.c b/drivers/acpi/acpi_apd.c
index 0ec5b3f69112..6e02448d15d9 100644
--- a/drivers/acpi/acpi_apd.c
+++ b/drivers/acpi/acpi_apd.c
@@ -226,6 +226,7 @@ static const struct acpi_device_id acpi_apd_device_ids[] = {
 	{ "AMDI0010", APD_ADDR(wt_i2c_desc) },
 	{ "AMD0020", APD_ADDR(cz_uart_desc) },
 	{ "AMDI0020", APD_ADDR(cz_uart_desc) },
+	{ "AMDI0022", APD_ADDR(cz_uart_desc) },
 	{ "AMD0030", },
 	{ "AMD0040", APD_ADDR(fch_misc_desc)},
 	{ "HYGO0010", APD_ADDR(wt_i2c_desc) },
diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c
index 16c0fe8a72a7..d260bc1f3e6e 100644
--- a/drivers/acpi/device_pm.c
+++ b/drivers/acpi/device_pm.c
@@ -1313,6 +1313,7 @@ int acpi_dev_pm_attach(struct device *dev, bool power_on)
 		{"PNP0C0B", }, /* Generic ACPI fan */
 		{"INT3404", }, /* Fan */
 		{"INTC1044", }, /* Fan for Tiger Lake generation */
+		{"INTC1048", }, /* Fan for Alder Lake generation */
 		{}
 	};
 	struct acpi_device *adev = ACPI_COMPANION(dev);
diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
index b852cff80287..e21611c9a170 100644
--- a/drivers/acpi/internal.h
+++ b/drivers/acpi/internal.h
@@ -134,7 +134,7 @@ int acpi_power_init(void);
 void acpi_power_resources_list_free(struct list_head *list);
 int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
 				 struct list_head *list);
-int acpi_add_power_resource(acpi_handle handle);
+struct acpi_device *acpi_add_power_resource(acpi_handle handle);
 void acpi_power_add_remove_device(struct acpi_device *adev, bool add);
 int acpi_power_wakeup_list_init(struct list_head *list, int *system_level);
 int acpi_device_sleep_wake(struct acpi_device *dev,
@@ -142,6 +142,7 @@ int acpi_device_sleep_wake(struct acpi_device *dev,
 int acpi_power_get_inferred_state(struct acpi_device *device, int *state);
 int acpi_power_on_resources(struct acpi_device *device, int state);
 int acpi_power_transition(struct acpi_device *device, int state);
+void acpi_turn_off_unused_power_resources(bool init);
 
 /* --------------------------------------------------------------------------
                               Device Power Management
diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index 958aaac869e8..23d9a09d7060 100644
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -686,6 +686,13 @@ int nfit_spa_type(struct acpi_nfit_system_address *spa)
 	return -1;
 }
 
+static size_t sizeof_spa(struct acpi_nfit_system_address *spa)
+{
+	if (spa->flags & ACPI_NFIT_LOCATION_COOKIE_VALID)
+		return sizeof(*spa);
+	return sizeof(*spa) - 8;
+}
+
 static bool add_spa(struct acpi_nfit_desc *acpi_desc,
 		struct nfit_table_prev *prev,
 		struct acpi_nfit_system_address *spa)
@@ -693,22 +700,22 @@ static bool add_spa(struct acpi_nfit_desc *acpi_desc,
 	struct device *dev = acpi_desc->dev;
 	struct nfit_spa *nfit_spa;
 
-	if (spa->header.length != sizeof(*spa))
+	if (spa->header.length != sizeof_spa(spa))
 		return false;
 
 	list_for_each_entry(nfit_spa, &prev->spas, list) {
-		if (memcmp(nfit_spa->spa, spa, sizeof(*spa)) == 0) {
+		if (memcmp(nfit_spa->spa, spa, sizeof_spa(spa)) == 0) {
 			list_move_tail(&nfit_spa->list, &acpi_desc->spas);
 			return true;
 		}
 	}
 
-	nfit_spa = devm_kzalloc(dev, sizeof(*nfit_spa) + sizeof(*spa),
+	nfit_spa = devm_kzalloc(dev, sizeof(*nfit_spa) + sizeof_spa(spa),
 			GFP_KERNEL);
 	if (!nfit_spa)
 		return false;
 	INIT_LIST_HEAD(&nfit_spa->list);
-	memcpy(nfit_spa->spa, spa, sizeof(*spa));
+	memcpy(nfit_spa->spa, spa, sizeof_spa(spa));
 	list_add_tail(&nfit_spa->list, &acpi_desc->spas);
 	dev_dbg(dev, "spa index: %d type: %s\n",
 			spa->range_index,
diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c
index 32974b575e46..97c9a94a1a30 100644
--- a/drivers/acpi/power.c
+++ b/drivers/acpi/power.c
@@ -52,6 +52,7 @@ struct acpi_power_resource {
 	u32 system_level;
 	u32 order;
 	unsigned int ref_count;
+	unsigned int users;
 	bool wakeup_enabled;
 	struct mutex resource_lock;
 	struct list_head dependents;
@@ -147,6 +148,7 @@ int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
 
 	for (i = start; i < package->package.count; i++) {
 		union acpi_object *element = &package->package.elements[i];
+		struct acpi_device *rdev;
 		acpi_handle rhandle;
 
 		if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
@@ -163,13 +165,16 @@ int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
 		if (acpi_power_resource_is_dup(package, start, i))
 			continue;
 
-		err = acpi_add_power_resource(rhandle);
-		if (err)
+		rdev = acpi_add_power_resource(rhandle);
+		if (!rdev) {
+			err = -ENODEV;
 			break;
-
+		}
 		err = acpi_power_resources_list_add(rhandle, list);
 		if (err)
 			break;
+
+		to_power_resource(rdev)->users++;
 	}
 	if (err)
 		acpi_power_resources_list_free(list);
@@ -907,7 +912,7 @@ static void acpi_power_add_resource_to_list(struct acpi_power_resource *resource
 	mutex_unlock(&power_resource_list_lock);
 }
 
-int acpi_add_power_resource(acpi_handle handle)
+struct acpi_device *acpi_add_power_resource(acpi_handle handle)
 {
 	struct acpi_power_resource *resource;
 	struct acpi_device *device = NULL;
@@ -918,11 +923,11 @@ int acpi_add_power_resource(acpi_handle handle)
 
 	acpi_bus_get_device(handle, &device);
 	if (device)
-		return 0;
+		return device;
 
 	resource = kzalloc(sizeof(*resource), GFP_KERNEL);
 	if (!resource)
-		return -ENOMEM;
+		return NULL;
 
 	device = &resource->device;
 	acpi_init_device_object(device, handle, ACPI_BUS_TYPE_POWER);
@@ -959,11 +964,11 @@ int acpi_add_power_resource(acpi_handle handle)
 
 	acpi_power_add_resource_to_list(resource);
 	acpi_device_add_finalize(device);
-	return 0;
+	return device;
 
  err:
 	acpi_release_power_resource(&device->dev);
-	return result;
+	return NULL;
 }
 
 #ifdef CONFIG_ACPI_SLEEP
@@ -995,8 +1000,40 @@ void acpi_resume_power_resources(void)
 
 	mutex_unlock(&power_resource_list_lock);
 }
+#endif
+
+static void acpi_power_turn_off_if_unused(struct acpi_power_resource *resource,
+				       bool init)
+{
+	if (resource->ref_count > 0)
+		return;
+
+	if (init) {
+		if (resource->users > 0)
+			return;
+	} else {
+		int result, state;
+
+		result = acpi_power_get_state(resource->device.handle, &state);
+		if (result || state == ACPI_POWER_RESOURCE_STATE_OFF)
+			return;
+	}
+
+	dev_info(&resource->device.dev, "Turning OFF\n");
+	__acpi_power_off(resource);
+}
 
-void acpi_turn_off_unused_power_resources(void)
+/**
+ * acpi_turn_off_unused_power_resources - Turn off power resources not in use.
+ * @init: Control switch.
+ *
+ * If @ainit is set, unconditionally turn off all of the ACPI power resources
+ * without any users.
+ *
+ * Otherwise, turn off all ACPI power resources without active references (that
+ * is, the ones that should be "off" at the moment) that are "on".
+ */
+void acpi_turn_off_unused_power_resources(bool init)
 {
 	struct acpi_power_resource *resource;
 
@@ -1005,14 +1042,10 @@ void acpi_turn_off_unused_power_resources(void)
 	list_for_each_entry_reverse(resource, &acpi_power_resource_list, list_node) {
 		mutex_lock(&resource->resource_lock);
 
-		if (!resource->ref_count) {
-			dev_info(&resource->device.dev, "Turning OFF\n");
-			__acpi_power_off(resource);
-		}
+		acpi_power_turn_off_if_unused(resource, init);
 
 		mutex_unlock(&resource->resource_lock);
 	}
 
 	mutex_unlock(&power_resource_list_lock);
 }
-#endif
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index a22778e880c2..e10d38ac7cf2 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -700,6 +700,7 @@ int acpi_device_add(struct acpi_device *device,
 
 		result = acpi_device_set_name(device, acpi_device_bus_id);
 		if (result) {
+			kfree_const(acpi_device_bus_id->bus_id);
 			kfree(acpi_device_bus_id);
 			goto err_unlock;
 		}
@@ -2359,6 +2360,8 @@ int __init acpi_scan_init(void)
 		}
 	}
 
+	acpi_turn_off_unused_power_resources(true);
+
 	acpi_scan_initialized = true;
 
  out:
diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c
index 09fd13757b65..df386571da98 100644
--- a/drivers/acpi/sleep.c
+++ b/drivers/acpi/sleep.c
@@ -504,7 +504,7 @@ static void acpi_pm_start(u32 acpi_state)
  */
 static void acpi_pm_end(void)
 {
-	acpi_turn_off_unused_power_resources();
+	acpi_turn_off_unused_power_resources(false);
 	acpi_scan_lock_release();
 	/*
 	 * This is necessary in case acpi_pm_finish() is not called during a
diff --git a/drivers/acpi/sleep.h b/drivers/acpi/sleep.h
index 1856f76ac83f..7fe41ee489d6 100644
--- a/drivers/acpi/sleep.h
+++ b/drivers/acpi/sleep.h
@@ -8,7 +8,6 @@ extern struct list_head acpi_wakeup_device_list;
 extern struct mutex acpi_device_lock;
 
 extern void acpi_resume_power_resources(void);
-extern void acpi_turn_off_unused_power_resources(void);
 
 static inline acpi_status acpi_set_waking_vector(u32 wakeup_address)
 {