Merge branches 'acpi-apei', 'acpi-pmic', 'acpi-video' and 'acpi-dptf'

* acpi-apei:
  arm64: acpi: Make apei_claim_sea() synchronise with APEI's irq work
  ACPI: APEI: Kick the memory_failure() queue for synchronous errors
  mm/memory-failure: Add memory_failure_queue_kick()

* acpi-pmic:
  ACPI / PMIC: Add i2c address for thermal control

* acpi-video:
  ACPI: video: Use native backlight on Acer TravelMate 5735Z

* acpi-dptf:
  ACPI: DPTF: Add battery participant driver
  ACPI: DPTF: Additional sysfs attributes for power participant driver

Author: rafaeljw

Documentation/ABI/testing/sysfs-platform-dptf

@@ -27,14 +27,68 @@ KernelVersion:	v4.10
 Contact:	linux-acpi@vger.kernel.org
 Description:
 		(RO) Display the platform power source
-		0x00 = DC
-		0x01 = AC
-		0x02 = USB
-		0x03 = Wireless Charger
+		bits[3:0] Current power source
+			0x00 = DC
+			0x01 = AC
+			0x02 = USB
+			0x03 = Wireless Charger
+		bits[7:4] Power source sequence number
 
 What:		/sys/bus/platform/devices/INT3407:00/dptf_power/battery_steady_power
 Date:		Jul, 2016
 KernelVersion:	v4.10
 Contact:	linux-acpi@vger.kernel.org
 Description:
 		(RO) The maximum sustained power for battery in milliwatts.
+
+What:		/sys/bus/platform/devices/INT3407:00/dptf_power/rest_of_platform_power_mw
+Date:		June, 2020
+KernelVersion:	v5.8
+Contact:	linux-acpi@vger.kernel.org
+Description:
+		(RO) Shows the rest (outside of SoC) of worst-case platform power.
+
+What:		/sys/bus/platform/devices/INT3407:00/dptf_power/prochot_confirm
+Date:		June, 2020
+KernelVersion:	v5.8
+Contact:	linux-acpi@vger.kernel.org
+Description:
+		(WO) Confirm embedded controller about a prochot notification.
+
+What:		/sys/bus/platform/devices/INT3532:00/dptf_battery/max_platform_power_mw
+Date:		June, 2020
+KernelVersion:	v5.8
+Contact:	linux-acpi@vger.kernel.org
+Description:
+		(RO) The maximum platform power that can be supported by the battery in milli watts.
+
+What:		/sys/bus/platform/devices/INT3532:00/dptf_battery/max_steady_state_power_mw
+Date:		June, 2020
+KernelVersion:	v5.8
+Contact:	linux-acpi@vger.kernel.org
+Description:
+		(RO) The maximum sustained power for battery in milli watts.
+
+What:		/sys/bus/platform/devices/INT3532:00/dptf_battery/high_freq_impedance_mohm
+Date:		June, 2020
+KernelVersion:	v5.8
+Contact:	linux-acpi@vger.kernel.org
+Description:
+		(RO) The high frequency impedance value that can be obtained from battery
+		fuel gauge in milli Ohms.
+
+What:		/sys/bus/platform/devices/INT3532:00/dptf_battery/no_load_voltage_mv
+Date:		June, 2020
+KernelVersion:	v5.8
+Contact:	linux-acpi@vger.kernel.org
+Description:
+		(RO) The no-load voltage that can be obtained from battery fuel gauge in
+		milli volts.
+
+What:		/sys/bus/platform/devices/INT3532:00/dptf_battery/current_discharge_capbility_ma
+Date:		June, 2020
+KernelVersion:	v5.8
+Contact:	linux-acpi@vger.kernel.org
+Description:
+		(RO) The battery discharge current capability obtained from battery fuel gauge in
+		milli Amps.

arch/arm64/kernel/acpi.c

@@ -19,6 +19,7 @@
 #include <linux/init.h>
 #include <linux/irq.h>
 #include <linux/irqdomain.h>
+#include <linux/irq_work.h>
 #include <linux/memblock.h>
 #include <linux/of_fdt.h>
 #include <linux/smp.h>
@@ -269,13 +270,20 @@ pgprot_t __acpi_get_mem_attribute(phys_addr_t addr)
 int apei_claim_sea(struct pt_regs *regs)
 {
 	int err = -ENOENT;
+	bool return_to_irqs_enabled;
 	unsigned long current_flags;
 
 	if (!IS_ENABLED(CONFIG_ACPI_APEI_GHES))
 		return err;
 
 	current_flags = local_daif_save_flags();
 
+	/* current_flags isn't useful here as daif doesn't tell us about pNMI */
+	return_to_irqs_enabled = !irqs_disabled_flags(arch_local_save_flags());
+
+	if (regs)
+		return_to_irqs_enabled = interrupts_enabled(regs);
+
 	/*
 	 * SEA can interrupt SError, mask it and describe this as an NMI so
 	 * that APEI defers the handling.
@@ -284,6 +292,23 @@ int apei_claim_sea(struct pt_regs *regs)
 	nmi_enter();
 	err = ghes_notify_sea();
 	nmi_exit();
+
+	/*
+	 * APEI NMI-like notifications are deferred to irq_work. Unless
+	 * we interrupted irqs-masked code, we can do that now.
+	 */
+	if (!err) {
+		if (return_to_irqs_enabled) {
+			local_daif_restore(DAIF_PROCCTX_NOIRQ);
+			__irq_enter();
+			irq_work_run();
+			__irq_exit();
+		} else {
+			pr_warn_ratelimited("APEI work queued but not completed");
+			err = -EINPROGRESS;
+		}
+	}
+
 	local_daif_restore(current_flags);
 
 	return err;

arch/arm64/mm/fault.c

@@ -635,11 +635,13 @@ static int do_sea(unsigned long addr, unsigned int esr, struct pt_regs *regs)
 
 	inf = esr_to_fault_info(esr);
 
-	/*
-	 * Return value ignored as we rely on signal merging.
-	 * Future patches will make this more robust.
-	 */
-	apei_claim_sea(regs);
+	if (user_mode(regs) && apei_claim_sea(regs) == 0) {
+		/*
+		 * APEI claimed this as a firmware-first notification.
+		 * Some processing deferred to task_work before ret_to_user().
+		 */
+		return 0;
+	}
 
 	if (esr & ESR_ELx_FnV)
 		siaddr = NULL;

drivers/acpi/apei/ghes.c

@@ -40,6 +40,7 @@
 #include <linux/sched/clock.h>
 #include <linux/uuid.h>
 #include <linux/ras.h>
+#include <linux/task_work.h>
 
 #include <acpi/actbl1.h>
 #include <acpi/ghes.h>
@@ -414,23 +415,46 @@ static void ghes_clear_estatus(struct ghes *ghes,
 		ghes_ack_error(ghes->generic_v2);
 }
 
-static void ghes_handle_memory_failure(struct acpi_hest_generic_data *gdata, int sev)
+/*
+ * Called as task_work before returning to user-space.
+ * Ensure any queued work has been done before we return to the context that
+ * triggered the notification.
+ */
+static void ghes_kick_task_work(struct callback_head *head)
+{
+	struct acpi_hest_generic_status *estatus;
+	struct ghes_estatus_node *estatus_node;
+	u32 node_len;
+
+	estatus_node = container_of(head, struct ghes_estatus_node, task_work);
+	if (IS_ENABLED(CONFIG_ACPI_APEI_MEMORY_FAILURE))
+		memory_failure_queue_kick(estatus_node->task_work_cpu);
+
+	estatus = GHES_ESTATUS_FROM_NODE(estatus_node);
+	node_len = GHES_ESTATUS_NODE_LEN(cper_estatus_len(estatus));
+	gen_pool_free(ghes_estatus_pool, (unsigned long)estatus_node, node_len);
+}
+
+static bool ghes_handle_memory_failure(struct acpi_hest_generic_data *gdata,
+				       int sev)
 {
-#ifdef CONFIG_ACPI_APEI_MEMORY_FAILURE
 	unsigned long pfn;
 	int flags = -1;
 	int sec_sev = ghes_severity(gdata->error_severity);
 	struct cper_sec_mem_err *mem_err = acpi_hest_get_payload(gdata);
 
+	if (!IS_ENABLED(CONFIG_ACPI_APEI_MEMORY_FAILURE))
+		return false;
+
 	if (!(mem_err->validation_bits & CPER_MEM_VALID_PA))
-		return;
+		return false;
 
 	pfn = mem_err->physical_addr >> PAGE_SHIFT;
 	if (!pfn_valid(pfn)) {
 		pr_warn_ratelimited(FW_WARN GHES_PFX
 		"Invalid address in generic error data: %#llx\n",
 		mem_err->physical_addr);
-		return;
+		return false;
 	}
 
 	/* iff following two events can be handled properly by now */
@@ -440,9 +464,12 @@ static void ghes_handle_memory_failure(struct acpi_hest_generic_data *gdata, int
 	if (sev == GHES_SEV_RECOVERABLE && sec_sev == GHES_SEV_RECOVERABLE)
 		flags = 0;
 
-	if (flags != -1)
+	if (flags != -1) {
 		memory_failure_queue(pfn, flags);
-#endif
+		return true;
+	}
+
+	return false;
 }
 
 /*
@@ -490,14 +517,15 @@ static void ghes_handle_aer(struct acpi_hest_generic_data *gdata)
 #endif
 }
 
-static void ghes_do_proc(struct ghes *ghes,
+static bool ghes_do_proc(struct ghes *ghes,
 			 const struct acpi_hest_generic_status *estatus)
 {
 	int sev, sec_sev;
 	struct acpi_hest_generic_data *gdata;
 	guid_t *sec_type;
 	const guid_t *fru_id = &guid_null;
 	char *fru_text = "";
+	bool queued = false;
 
 	sev = ghes_severity(estatus->error_severity);
 	apei_estatus_for_each_section(estatus, gdata) {
@@ -515,7 +543,7 @@ static void ghes_do_proc(struct ghes *ghes,
 			ghes_edac_report_mem_error(sev, mem_err);
 
 			arch_apei_report_mem_error(sev, mem_err);
-			ghes_handle_memory_failure(gdata, sev);
+			queued = ghes_handle_memory_failure(gdata, sev);
 		}
 		else if (guid_equal(sec_type, &CPER_SEC_PCIE)) {
 			ghes_handle_aer(gdata);
@@ -532,6 +560,8 @@ static void ghes_do_proc(struct ghes *ghes,
 					       gdata->error_data_length);
 		}
 	}
+
+	return queued;
 }
 
 static void __ghes_print_estatus(const char *pfx,
@@ -827,7 +857,9 @@ static void ghes_proc_in_irq(struct irq_work *irq_work)
 	struct ghes_estatus_node *estatus_node;
 	struct acpi_hest_generic *generic;
 	struct acpi_hest_generic_status *estatus;
+	bool task_work_pending;
 	u32 len, node_len;
+	int ret;
 
 	llnode = llist_del_all(&ghes_estatus_llist);
 	/*
@@ -842,14 +874,26 @@ static void ghes_proc_in_irq(struct irq_work *irq_work)
 		estatus = GHES_ESTATUS_FROM_NODE(estatus_node);
 		len = cper_estatus_len(estatus);
 		node_len = GHES_ESTATUS_NODE_LEN(len);
-		ghes_do_proc(estatus_node->ghes, estatus);
+		task_work_pending = ghes_do_proc(estatus_node->ghes, estatus);
 		if (!ghes_estatus_cached(estatus)) {
 			generic = estatus_node->generic;
 			if (ghes_print_estatus(NULL, generic, estatus))
 				ghes_estatus_cache_add(generic, estatus);
 		}
-		gen_pool_free(ghes_estatus_pool, (unsigned long)estatus_node,
-			      node_len);
+
+		if (task_work_pending && current->mm != &init_mm) {
+			estatus_node->task_work.func = ghes_kick_task_work;
+			estatus_node->task_work_cpu = smp_processor_id();
+			ret = task_work_add(current, &estatus_node->task_work,
+					    true);
+			if (ret)
+				estatus_node->task_work.func = NULL;
+		}
+
+		if (!estatus_node->task_work.func)
+			gen_pool_free(ghes_estatus_pool,
+				      (unsigned long)estatus_node, node_len);
+
 		llnode = next;
 	}
 }
@@ -909,6 +953,7 @@ static int ghes_in_nmi_queue_one_entry(struct ghes *ghes,
 
 	estatus_node->ghes = ghes;
 	estatus_node->generic = ghes->generic;
+	estatus_node->task_work.func = NULL;
 	estatus = GHES_ESTATUS_FROM_NODE(estatus_node);
 
 	if (__ghes_read_estatus(estatus, buf_paddr, fixmap_idx, len)) {