Merge tag 'driver-core-5.10-rc1' of...

Merge tag 'driver-core-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the "big" set of driver core patches for 5.10-rc1

  They include a lot of different things, all related to the driver core
  and/or some driver logic:

   - sysfs common write functions to make it easier to audit sysfs
     attributes

   - device connection cleanups and fixes

   - devm helpers for a few functions

   - NOIO allocations for when devices are being removed

   - minor cleanups and fixes

  All have been in linux-next for a while with no reported issues"

* tag 'driver-core-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (31 commits)
  regmap: debugfs: use semicolons rather than commas to separate statements
  platform/x86: intel_pmc_core: do not create a static struct device
  drivers core: node: Use a more typical macro definition style for ACCESS_ATTR
  drivers core: Use sysfs_emit for shared_cpu_map_show and shared_cpu_list_show
  mm: and drivers core: Convert hugetlb_report_node_meminfo to sysfs_emit
  drivers core: Miscellaneous changes for sysfs_emit
  drivers core: Reindent a couple uses around sysfs_emit
  drivers core: Remove strcat uses around sysfs_emit and neaten
  drivers core: Use sysfs_emit and sysfs_emit_at for show(device *...) functions
  sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs output
  dyndbg: use keyword, arg varnames for query term pairs
  driver core: force NOIO allocations during unplug
  platform_device: switch to simpler IDA interface
  driver core: platform: Document return type of more functions
  Revert "driver core: Annotate dev_err_probe() with __must_check"
  Revert "test_firmware: Test platform fw loading on non-EFI systems"
  iio: adc: xilinx-xadc: use devm_krealloc()
  hwmon: pmbus: use more devres helpers
  devres: provide devm_krealloc()
  syscore: Use pm_pr_dbg() for syscore_{suspend,resume}()
  ...

Documentation/driver-api/device_connection.rst

-==================
-Device connections
-==================
-
-Introduction
-------------
-
-Devices often have connections to other devices that are outside of the direct
-child/parent relationship. A serial or network communication controller, which
-could be a PCI device, may need to be able to get a reference to its PHY
-component, which could be attached for example to the I2C bus. Some device
-drivers need to be able to control the clocks or the GPIOs for their devices,
-and so on.
-
-Device connections are generic descriptions of any type of connection between
-two separate devices.
-
-Device connections alone do not create a dependency between the two devices.
-They are only descriptions which are not tied to either of the devices directly.
-A dependency between the two devices exists only if one of the two endpoint
-devices requests a reference to the other. The descriptions themselves can be
-defined in firmware (not yet supported) or they can be built-in.
-
-Usage
------
-
-Device connections should exist before device ``->probe`` callback is called for
-either endpoint device in the description. If the connections are defined in
-firmware, this is not a problem. It should be considered if the connection
-descriptions are "built-in", and need to be added separately.
-
-The connection description consists of the names of the two devices with the
-connection, i.e. the endpoints, and unique identifier for the connection which
-is needed if there are multiple connections between the two devices.
-
-After a description exists, the devices in it can request reference to the other
-endpoint device, or they can request the description itself.
-
-API
----
-
-.. kernel-doc:: drivers/base/devcon.c
-   :functions: device_connection_find_match device_connection_find device_connection_add device_connection_remove

Documentation/driver-api/driver-model/devres.rst

@@ -354,6 +354,7 @@ MEM
   devm_kmalloc()
   devm_kmalloc_array()
   devm_kmemdup()
+  devm_krealloc()
   devm_kstrdup()
   devm_kvasprintf()
   devm_kzalloc()

Documentation/driver-api/firmware/fallback-mechanisms.rst

@@ -42,6 +42,7 @@ fallback mechanism:
   supported for request_firmware_into_buf().
 
 * Firmware is not accessible through typical means:
+
         * It cannot be installed into the root filesystem
         * The firmware provides very unique device specific data tailored for
           the unit gathered with local information. An example is calibration

Documentation/driver-api/index.rst

@@ -22,7 +22,6 @@ available subsections can be seen below.
    pm/index
    clk
    device-io
-   device_connection
    dma-buf
    device_link
    component

Documentation/filesystems/sysfs.rst

@@ -241,12 +241,10 @@ Other notes:
   is 4096.
 
 - show() methods should return the number of bytes printed into the
-  buffer. This is the return value of scnprintf().
+  buffer.
 
-- show() must not use snprintf() when formatting the value to be
-  returned to user space. If you can guarantee that an overflow
-  will never happen you can use sprintf() otherwise you must use
-  scnprintf().
+- show() should only use sysfs_emit() or sysfs_emit_at() when formatting
+  the value to be returned to user space.
 
 - store() should return the number of bytes used from the buffer. If the
   entire buffer has been used, just return the count argument.

MAINTAINERS

@@ -5023,6 +5023,12 @@ S:	Maintained
 F:	drivers/base/devcoredump.c
 F:	include/linux/devcoredump.h
 
+DEVICE DEPENDENCY HELPER SCRIPT
+M:	Saravana Kannan <saravanak@google.com>
+L:	linux-kernel@vger.kernel.org
+S:	Maintained
+F:	scripts/dev-needs.sh
+
 DEVICE DIRECT ACCESS (DAX)
 M:	Dan Williams <dan.j.williams@intel.com>
 M:	Vishal Verma <vishal.l.verma@intel.com>

drivers/base/Makefile

@@ -6,7 +6,7 @@ obj-y			:= component.o core.o bus.o dd.o syscore.o \
 			   cpu.o firmware.o init.o map.o devres.o \
 			   attribute_container.o transport_class.o \
 			   topology.o container.o property.o cacheinfo.o \
-			   devcon.o swnode.o
+			   swnode.o
 obj-$(CONFIG_DEVTMPFS)	+= devtmpfs.o
 obj-y			+= power/
 obj-$(CONFIG_ISA_BUS_API)	+= isa.o

drivers/base/arch_topology.c

@@ -80,7 +80,7 @@ static ssize_t cpu_capacity_show(struct device *dev,
 {
 	struct cpu *cpu = container_of(dev, struct cpu, dev);
 
-	return sprintf(buf, "%lu\n", topology_get_cpu_scale(cpu->dev.id));
+	return sysfs_emit(buf, "%lu\n", topology_get_cpu_scale(cpu->dev.id));
 }
 
 static void update_topology_flags_workfn(struct work_struct *work);

drivers/base/bus.c

@@ -229,7 +229,7 @@ static DRIVER_ATTR_IGNORE_LOCKDEP(bind, S_IWUSR, NULL, bind_store);
 
 static ssize_t drivers_autoprobe_show(struct bus_type *bus, char *buf)
 {
-	return sprintf(buf, "%d\n", bus->p->drivers_autoprobe);
+	return sysfs_emit(buf, "%d\n", bus->p->drivers_autoprobe);
 }
 
 static ssize_t drivers_autoprobe_store(struct bus_type *bus,

drivers/base/cacheinfo.c

@@ -362,7 +362,7 @@ static ssize_t file_name##_show(struct device *dev,		\
 		struct device_attribute *attr, char *buf)	\
 {								\
 	struct cacheinfo *this_leaf = dev_get_drvdata(dev);	\
-	return sprintf(buf, "%u\n", this_leaf->object);		\
+	return sysfs_emit(buf, "%u\n", this_leaf->object);	\
 }
 
 show_one(id, id);
@@ -377,44 +377,48 @@ static ssize_t size_show(struct device *dev,
 {
 	struct cacheinfo *this_leaf = dev_get_drvdata(dev);
 
-	return sprintf(buf, "%uK\n", this_leaf->size >> 10);
+	return sysfs_emit(buf, "%uK\n", this_leaf->size >> 10);
 }
 
-static ssize_t shared_cpumap_show_func(struct device *dev, bool list, char *buf)
+static ssize_t shared_cpu_map_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
 {
 	struct cacheinfo *this_leaf = dev_get_drvdata(dev);
 	const struct cpumask *mask = &this_leaf->shared_cpu_map;
 
-	return cpumap_print_to_pagebuf(list, buf, mask);
-}
-
-static ssize_t shared_cpu_map_show(struct device *dev,
-				   struct device_attribute *attr, char *buf)
-{
-	return shared_cpumap_show_func(dev, false, buf);
+	return sysfs_emit(buf, "%*pb\n", nr_cpu_ids, mask);
 }
 
 static ssize_t shared_cpu_list_show(struct device *dev,
 				    struct device_attribute *attr, char *buf)
 {
-	return shared_cpumap_show_func(dev, true, buf);
+	struct cacheinfo *this_leaf = dev_get_drvdata(dev);
+	const struct cpumask *mask = &this_leaf->shared_cpu_map;
+
+	return sysfs_emit(buf, "%*pbl\n", nr_cpu_ids, mask);
 }
 
 static ssize_t type_show(struct device *dev,
 			 struct device_attribute *attr, char *buf)
 {
 	struct cacheinfo *this_leaf = dev_get_drvdata(dev);
+	const char *output;
 
 	switch (this_leaf->type) {
 	case CACHE_TYPE_DATA:
-		return sprintf(buf, "Data\n");
+		output = "Data";
+		break;
 	case CACHE_TYPE_INST:
-		return sprintf(buf, "Instruction\n");
+		output = "Instruction";
+		break;
 	case CACHE_TYPE_UNIFIED:
-		return sprintf(buf, "Unified\n");
+		output = "Unified";
+		break;
 	default:
 		return -EINVAL;
 	}
+
+	return sysfs_emit(buf, "%s\n", output);
 }
 
 static ssize_t allocation_policy_show(struct device *dev,
@@ -422,15 +426,18 @@ static ssize_t allocation_policy_show(struct device *dev,
 {
 	struct cacheinfo *this_leaf = dev_get_drvdata(dev);
 	unsigned int ci_attr = this_leaf->attributes;
-	int n = 0;
+	const char *output;
 
 	if ((ci_attr & CACHE_READ_ALLOCATE) && (ci_attr & CACHE_WRITE_ALLOCATE))
-		n = sprintf(buf, "ReadWriteAllocate\n");
+		output = "ReadWriteAllocate";
 	else if (ci_attr & CACHE_READ_ALLOCATE)
-		n = sprintf(buf, "ReadAllocate\n");
+		output = "ReadAllocate";
 	else if (ci_attr & CACHE_WRITE_ALLOCATE)
-		n = sprintf(buf, "WriteAllocate\n");
-	return n;
+		output = "WriteAllocate";
+	else
+		return 0;
+
+	return sysfs_emit(buf, "%s\n", output);
 }
 
 static ssize_t write_policy_show(struct device *dev,
@@ -441,9 +448,9 @@ static ssize_t write_policy_show(struct device *dev,
 	int n = 0;
 
 	if (ci_attr & CACHE_WRITE_THROUGH)
-		n = sprintf(buf, "WriteThrough\n");
+		n = sysfs_emit(buf, "WriteThrough\n");
 	else if (ci_attr & CACHE_WRITE_BACK)
-		n = sprintf(buf, "WriteBack\n");
+		n = sysfs_emit(buf, "WriteBack\n");
 	return n;
 }
 

drivers/base/class.c

@@ -478,7 +478,7 @@ ssize_t show_class_attr_string(struct class *class,
 	struct class_attribute_string *cs;
 
 	cs = container_of(attr, struct class_attribute_string, attr);
-	return snprintf(buf, PAGE_SIZE, "%s\n", cs->str);
+	return sysfs_emit(buf, "%s\n", cs->str);
 }
 
 EXPORT_SYMBOL_GPL(show_class_attr_string);

drivers/base/core.c

@@ -26,6 +26,7 @@
 #include <linux/pm_runtime.h>
 #include <linux/netdevice.h>
 #include <linux/sched/signal.h>
+#include <linux/sched/mm.h>
 #include <linux/sysfs.h>
 
 #include "base.h"
@@ -239,27 +240,35 @@ void device_pm_move_to_tail(struct device *dev)
 #define to_devlink(dev)	container_of((dev), struct device_link, link_dev)
 
 static ssize_t status_show(struct device *dev,
-			  struct device_attribute *attr, char *buf)
+			   struct device_attribute *attr, char *buf)
 {
-	char *status;
+	const char *output;
 
 	switch (to_devlink(dev)->status) {
 	case DL_STATE_NONE:
-		status = "not tracked"; break;
+		output = "not tracked";
+		break;
 	case DL_STATE_DORMANT:
-		status = "dormant"; break;
+		output = "dormant";
+		break;
 	case DL_STATE_AVAILABLE:
-		status = "available"; break;
+		output = "available";
+		break;
 	case DL_STATE_CONSUMER_PROBE:
-		status = "consumer probing"; break;
+		output = "consumer probing";
+		break;
 	case DL_STATE_ACTIVE:
-		status = "active"; break;
+		output = "active";
+		break;
 	case DL_STATE_SUPPLIER_UNBIND:
-		status = "supplier unbinding"; break;
+		output = "supplier unbinding";
+		break;
 	default:
-		status = "unknown"; break;
+		output = "unknown";
+		break;
 	}
-	return sprintf(buf, "%s\n", status);
+
+	return sysfs_emit(buf, "%s\n", output);
 }
 static DEVICE_ATTR_RO(status);
 
@@ -267,16 +276,16 @@ static ssize_t auto_remove_on_show(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {
 	struct device_link *link = to_devlink(dev);
-	char *str;
+	const char *output;
 
 	if (link->flags & DL_FLAG_AUTOREMOVE_SUPPLIER)
-		str = "supplier unbind";
+		output = "supplier unbind";
 	else if (link->flags & DL_FLAG_AUTOREMOVE_CONSUMER)
-		str = "consumer unbind";
+		output = "consumer unbind";
 	else
-		str = "never";
+		output = "never";
 
-	return sprintf(buf, "%s\n", str);
+	return sysfs_emit(buf, "%s\n", output);
 }
 static DEVICE_ATTR_RO(auto_remove_on);
 
@@ -285,7 +294,7 @@ static ssize_t runtime_pm_show(struct device *dev,
 {
 	struct device_link *link = to_devlink(dev);
 
-	return sprintf(buf, "%d\n", !!(link->flags & DL_FLAG_PM_RUNTIME));
+	return sysfs_emit(buf, "%d\n", !!(link->flags & DL_FLAG_PM_RUNTIME));
 }
 static DEVICE_ATTR_RO(runtime_pm);
 
@@ -294,7 +303,8 @@ static ssize_t sync_state_only_show(struct device *dev,
 {
 	struct device_link *link = to_devlink(dev);
 
-	return sprintf(buf, "%d\n", !!(link->flags & DL_FLAG_SYNC_STATE_ONLY));
+	return sysfs_emit(buf, "%d\n",
+			  !!(link->flags & DL_FLAG_SYNC_STATE_ONLY));
 }
 static DEVICE_ATTR_RO(sync_state_only);
 
@@ -1059,7 +1069,7 @@ static ssize_t waiting_for_supplier_show(struct device *dev,
 	      && dev->links.need_for_probe;
 	mutex_unlock(&wfs_lock);
 	device_unlock(dev);
-	return sprintf(buf, "%u\n", val);
+	return sysfs_emit(buf, "%u\n", val);
 }
 static DEVICE_ATTR_RO(waiting_for_supplier);
 
@@ -1709,7 +1719,7 @@ ssize_t device_show_ulong(struct device *dev,
 			  char *buf)
 {
 	struct dev_ext_attribute *ea = to_ext_attr(attr);
-	return snprintf(buf, PAGE_SIZE, "%lx\n", *(unsigned long *)(ea->var));
+	return sysfs_emit(buf, "%lx\n", *(unsigned long *)(ea->var));
 }
 EXPORT_SYMBOL_GPL(device_show_ulong);
 
@@ -1739,7 +1749,7 @@ ssize_t device_show_int(struct device *dev,
 {
 	struct dev_ext_attribute *ea = to_ext_attr(attr);
 
-	return snprintf(buf, PAGE_SIZE, "%d\n", *(int *)(ea->var));
+	return sysfs_emit(buf, "%d\n", *(int *)(ea->var));
 }
 EXPORT_SYMBOL_GPL(device_show_int);
 
@@ -1760,7 +1770,7 @@ ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
 {
 	struct dev_ext_attribute *ea = to_ext_attr(attr);
 
-	return snprintf(buf, PAGE_SIZE, "%d\n", *(bool *)(ea->var));
+	return sysfs_emit(buf, "%d\n", *(bool *)(ea->var));
 }
 EXPORT_SYMBOL_GPL(device_show_bool);
 
@@ -1932,7 +1942,7 @@ static ssize_t uevent_show(struct device *dev, struct device_attribute *attr,
 	struct kset *kset;
 	struct kobj_uevent_env *env = NULL;
 	int i;
-	size_t count = 0;
+	int len = 0;
 	int retval;
 
 	/* search the kset, the device belongs to */
@@ -1962,10 +1972,10 @@ static ssize_t uevent_show(struct device *dev, struct device_attribute *attr,
 
 	/* copy keys to file */
 	for (i = 0; i < env->envp_idx; i++)
-		count += sprintf(&buf[count], "%s\n", env->envp[i]);
+		len += sysfs_emit_at(buf, len, "%s\n", env->envp[i]);
 out:
 	kfree(env);
-	return count;
+	return len;
 }
 
 static ssize_t uevent_store(struct device *dev, struct device_attribute *attr,
@@ -1992,7 +2002,7 @@ static ssize_t online_show(struct device *dev, struct device_attribute *attr,
 	device_lock(dev);
 	val = !dev->offline;
 	device_unlock(dev);
-	return sprintf(buf, "%u\n", val);
+	return sysfs_emit(buf, "%u\n", val);
 }
 
 static ssize_t online_store(struct device *dev, struct device_attribute *attr,
@@ -3062,6 +3072,7 @@ void device_del(struct device *dev)
 	struct device *parent = dev->parent;
 	struct kobject *glue_dir = NULL;
 	struct class_interface *class_intf;
+	unsigned int noio_flag;
 
 	device_lock(dev);
 	kill_device(dev);
@@ -3073,6 +3084,7 @@ void device_del(struct device *dev)
 	/* Notify clients of device removal.  This call must come
 	 * before dpm_sysfs_remove().
 	 */
+	noio_flag = memalloc_noio_save();
 	if (dev->bus)
 		blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
 					     BUS_NOTIFY_DEL_DEVICE, dev);
@@ -3114,6 +3126,7 @@ void device_del(struct device *dev)
 	glue_dir = get_glue_dir(dev);
 	kobject_del(&dev->kobj);
 	cleanup_glue_dir(dev, glue_dir);
+	memalloc_noio_restore(noio_flag);
 	put_device(parent);
 }
 EXPORT_SYMBOL_GPL(device_del);

drivers/base/cpu.c

@@ -139,11 +139,11 @@ EXPORT_SYMBOL_GPL(cpu_subsys);
 #ifdef CONFIG_KEXEC
 #include <linux/kexec.h>
 
-static ssize_t show_crash_notes(struct device *dev, struct device_attribute *attr,
+static ssize_t crash_notes_show(struct device *dev,
+				struct device_attribute *attr,
 				char *buf)
 {
 	struct cpu *cpu = container_of(dev, struct cpu, dev);
-	ssize_t rc;
 	unsigned long long addr;
 	int cpunum;
 
@@ -156,21 +156,18 @@ static ssize_t show_crash_notes(struct device *dev, struct device_attribute *att
 	 * operation should be safe. No locking required.
 	 */
 	addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpunum));
-	rc = sprintf(buf, "%Lx\n", addr);
-	return rc;
+
+	return sysfs_emit(buf, "%llx\n", addr);
 }
-static DEVICE_ATTR(crash_notes, 0400, show_crash_notes, NULL);
+static DEVICE_ATTR_ADMIN_RO(crash_notes);
 
-static ssize_t show_crash_notes_size(struct device *dev,
+static ssize_t crash_notes_size_show(struct device *dev,
 				     struct device_attribute *attr,
 				     char *buf)
 {
-	ssize_t rc;
-
-	rc = sprintf(buf, "%zu\n", sizeof(note_buf_t));
-	return rc;
+	return sysfs_emit(buf, "%zu\n", sizeof(note_buf_t));
 }
-static DEVICE_ATTR(crash_notes_size, 0400, show_crash_notes_size, NULL);
+static DEVICE_ATTR_ADMIN_RO(crash_notes_size);
 
 static struct attribute *crash_note_cpu_attrs[] = {
 	&dev_attr_crash_notes.attr,
@@ -231,7 +228,7 @@ static struct cpu_attr cpu_attrs[] = {
 static ssize_t print_cpus_kernel_max(struct device *dev,
 				     struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%d\n", NR_CPUS - 1);
+	return sysfs_emit(buf, "%d\n", NR_CPUS - 1);
 }
 static DEVICE_ATTR(kernel_max, 0444, print_cpus_kernel_max, NULL);
 
@@ -241,37 +238,37 @@ unsigned int total_cpus;
 static ssize_t print_cpus_offline(struct device *dev,
 				  struct device_attribute *attr, char *buf)
 {
-	int n = 0, len = PAGE_SIZE-2;
+	int len = 0;
 	cpumask_var_t offline;
 
 	/* display offline cpus < nr_cpu_ids */
 	if (!alloc_cpumask_var(&offline, GFP_KERNEL))
 		return -ENOMEM;
 	cpumask_andnot(offline, cpu_possible_mask, cpu_online_mask);
-	n = scnprintf(buf, len, "%*pbl", cpumask_pr_args(offline));
+	len += sysfs_emit_at(buf, len, "%*pbl", cpumask_pr_args(offline));
 	free_cpumask_var(offline);
 
 	/* display offline cpus >= nr_cpu_ids */
 	if (total_cpus && nr_cpu_ids < total_cpus) {
-		if (n && n < len)
-			buf[n++] = ',';
+		len += sysfs_emit_at(buf, len, ",");
 
 		if (nr_cpu_ids == total_cpus-1)
-			n += scnprintf(&buf[n], len - n, "%u", nr_cpu_ids);
+			len += sysfs_emit_at(buf, len, "%u", nr_cpu_ids);
 		else
-			n += scnprintf(&buf[n], len - n, "%u-%d",
-						      nr_cpu_ids, total_cpus-1);
+			len += sysfs_emit_at(buf, len, "%u-%d",
+					     nr_cpu_ids, total_cpus - 1);
 	}
 
-	n += scnprintf(&buf[n], len - n, "\n");
-	return n;
+	len += sysfs_emit_at(buf, len, "\n");
+
+	return len;
 }
 static DEVICE_ATTR(offline, 0444, print_cpus_offline, NULL);
 
 static ssize_t print_cpus_isolated(struct device *dev,
 				  struct device_attribute *attr, char *buf)
 {
-	int n;
+	int len;
 	cpumask_var_t isolated;
 
 	if (!alloc_cpumask_var(&isolated, GFP_KERNEL))
@@ -279,19 +276,19 @@ static ssize_t print_cpus_isolated(struct device *dev,
 
 	cpumask_andnot(isolated, cpu_possible_mask,
 		       housekeeping_cpumask(HK_FLAG_DOMAIN));
-	n = sprintf(buf, "%*pbl\n", cpumask_pr_args(isolated));
+	len = sysfs_emit(buf, "%*pbl\n", cpumask_pr_args(isolated));
 
 	free_cpumask_var(isolated);
 
-	return n;
+	return len;
 }
 static DEVICE_ATTR(isolated, 0444, print_cpus_isolated, NULL);
 
 #ifdef CONFIG_NO_HZ_FULL
 static ssize_t print_cpus_nohz_full(struct device *dev,
-				  struct device_attribute *attr, char *buf)
+				    struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%*pbl\n", cpumask_pr_args(tick_nohz_full_mask));
+	return sysfs_emit(buf, "%*pbl\n", cpumask_pr_args(tick_nohz_full_mask));
 }
 static DEVICE_ATTR(nohz_full, 0444, print_cpus_nohz_full, NULL);
 #endif
@@ -320,22 +317,23 @@ static ssize_t print_cpu_modalias(struct device *dev,
 				  struct device_attribute *attr,
 				  char *buf)
 {
-	ssize_t n;
+	int len = 0;
 	u32 i;
 
-	n = sprintf(buf, "cpu:type:" CPU_FEATURE_TYPEFMT ":feature:",
-		    CPU_FEATURE_TYPEVAL);
+	len += sysfs_emit_at(buf, len,
+			     "cpu:type:" CPU_FEATURE_TYPEFMT ":feature:",
+			     CPU_FEATURE_TYPEVAL);
 
 	for (i = 0; i < MAX_CPU_FEATURES; i++)
 		if (cpu_have_feature(i)) {
-			if (PAGE_SIZE < n + sizeof(",XXXX\n")) {
+			if (len + sizeof(",XXXX\n") >= PAGE_SIZE) {
 				WARN(1, "CPU features overflow page\n");
 				break;
 			}
-			n += sprintf(&buf[n], ",%04X", i);
+			len += sysfs_emit_at(buf, len, ",%04X", i);
 		}
-	buf[n++] = '\n';
-	return n;
+	len += sysfs_emit_at(buf, len, "\n");
+	return len;
 }
 
 static int cpu_uevent(struct device *dev, struct kobj_uevent_env *env)
@@ -516,56 +514,56 @@ static void __init cpu_dev_register_generic(void)
 ssize_t __weak cpu_show_meltdown(struct device *dev,
 				 struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_spectre_v1(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_spectre_v2(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_spec_store_bypass(struct device *dev,
 					  struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_l1tf(struct device *dev,
 			     struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_mds(struct device *dev,
 			    struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_tsx_async_abort(struct device *dev,
 					struct device_attribute *attr,
 					char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_itlb_multihit(struct device *dev,
-			    struct device_attribute *attr, char *buf)
+				      struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_srbds(struct device *dev,
 			      struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 static DEVICE_ATTR(meltdown, 0444, cpu_show_meltdown, NULL);

drivers/base/dd.c

@@ -486,7 +486,8 @@ static ssize_t state_synced_show(struct device *dev,
 	device_lock(dev);
 	val = dev->state_synced;
 	device_unlock(dev);
-	return sprintf(buf, "%u\n", val);
+
+	return sysfs_emit(buf, "%u\n", val);
 }
 static DEVICE_ATTR_RO(state_synced);
 
@@ -658,15 +659,14 @@ static int really_probe(struct device *dev, struct device_driver *drv)
  */
 static int really_probe_debug(struct device *dev, struct device_driver *drv)
 {
-	ktime_t calltime, delta, rettime;
+	ktime_t calltime, rettime;
 	int ret;
 
 	calltime = ktime_get();
 	ret = really_probe(dev, drv);
 	rettime = ktime_get();
-	delta = ktime_sub(rettime, calltime);
 	pr_debug("probe of %s returned %d after %lld usecs\n",
-		 dev_name(dev), ret, (s64) ktime_to_us(delta));
+		 dev_name(dev), ret, ktime_us_delta(rettime, calltime));
 	return ret;
 }
 

drivers/base/devcon.c

-// SPDX-License-Identifier: GPL-2.0
-/**
- * Device connections
- *
- * Copyright (C) 2018 Intel Corporation
- * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com>
- */
-
-#include <linux/device.h>
-#include <linux/property.h>
-
-static DEFINE_MUTEX(devcon_lock);
-static LIST_HEAD(devcon_list);
-
-static void *
-fwnode_graph_devcon_match(struct fwnode_handle *fwnode, const char *con_id,
-			  void *data, devcon_match_fn_t match)
-{
-	struct device_connection con = { .id = con_id };
-	struct fwnode_handle *ep;
-	void *ret;
-
-	fwnode_graph_for_each_endpoint(fwnode, ep) {
-		con.fwnode = fwnode_graph_get_remote_port_parent(ep);
-		if (!fwnode_device_is_available(con.fwnode))
-			continue;
-
-		ret = match(&con, -1, data);
-		fwnode_handle_put(con.fwnode);
-		if (ret) {
-			fwnode_handle_put(ep);
-			return ret;
-		}
-	}
-	return NULL;
-}
-
-static void *
-fwnode_devcon_match(struct fwnode_handle *fwnode, const char *con_id,
-		    void *data, devcon_match_fn_t match)
-{
-	struct device_connection con = { };
-	void *ret;
-	int i;
-
-	for (i = 0; ; i++) {
-		con.fwnode = fwnode_find_reference(fwnode, con_id, i);
-		if (IS_ERR(con.fwnode))
-			break;
-
-		ret = match(&con, -1, data);
-		fwnode_handle_put(con.fwnode);
-		if (ret)
-			return ret;
-	}
-
-	return NULL;
-}
-
-/**
- * fwnode_connection_find_match - Find connection from a device node
- * @fwnode: Device node with the connection
- * @con_id: Identifier for the connection
- * @data: Data for the match function
- * @match: Function to check and convert the connection description
- *
- * Find a connection with unique identifier @con_id between @fwnode and another
- * device node. @match will be used to convert the connection description to
- * data the caller is expecting to be returned.
- */
-void *fwnode_connection_find_match(struct fwnode_handle *fwnode,
-				   const char *con_id, void *data,
-				   devcon_match_fn_t match)
-{
-	void *ret;
-
-	if (!fwnode || !match)
-		return NULL;
-
-	ret = fwnode_graph_devcon_match(fwnode, con_id, data, match);
-	if (ret)
-		return ret;
-
-	return fwnode_devcon_match(fwnode, con_id, data, match);
-}
-EXPORT_SYMBOL_GPL(fwnode_connection_find_match);
-
-/**
- * device_connection_find_match - Find physical connection to a device
- * @dev: Device with the connection
- * @con_id: Identifier for the connection
- * @data: Data for the match function
- * @match: Function to check and convert the connection description
- *
- * Find a connection with unique identifier @con_id between @dev and another
- * device. @match will be used to convert the connection description to data the
- * caller is expecting to be returned.
- */
-void *device_connection_find_match(struct device *dev, const char *con_id,
-				   void *data, devcon_match_fn_t match)
-{
-	struct fwnode_handle *fwnode = dev_fwnode(dev);
-	const char *devname = dev_name(dev);
-	struct device_connection *con;
-	void *ret = NULL;
-	int ep;
-
-	if (!match)
-		return NULL;
-
-	ret = fwnode_connection_find_match(fwnode, con_id, data, match);
-	if (ret)
-		return ret;
-
-	mutex_lock(&devcon_lock);
-
-	list_for_each_entry(con, &devcon_list, list) {
-		ep = match_string(con->endpoint, 2, devname);
-		if (ep < 0)
-			continue;
-
-		if (con_id && strcmp(con->id, con_id))
-			continue;
-
-		ret = match(con, !ep, data);
-		if (ret)
-			break;
-	}
-
-	mutex_unlock(&devcon_lock);
-
-	return ret;
-}
-EXPORT_SYMBOL_GPL(device_connection_find_match);
-
-extern struct bus_type platform_bus_type;
-extern struct bus_type pci_bus_type;
-extern struct bus_type i2c_bus_type;
-extern struct bus_type spi_bus_type;
-
-static struct bus_type *generic_match_buses[] = {
-	&platform_bus_type,
-#ifdef CONFIG_PCI
-	&pci_bus_type,
-#endif
-#ifdef CONFIG_I2C
-	&i2c_bus_type,
-#endif
-#ifdef CONFIG_SPI_MASTER
-	&spi_bus_type,
-#endif
-	NULL,
-};
-
-static void *device_connection_fwnode_match(struct device_connection *con)
-{
-	struct bus_type *bus;
-	struct device *dev;
-
-	for (bus = generic_match_buses[0]; bus; bus++) {
-		dev = bus_find_device_by_fwnode(bus, con->fwnode);
-		if (dev && !strncmp(dev_name(dev), con->id, strlen(con->id)))
-			return dev;
-
-		put_device(dev);
-	}
-	return NULL;
-}
-
-/* This tries to find the device from the most common bus types by name. */
-static void *generic_match(struct device_connection *con, int ep, void *data)
-{
-	struct bus_type *bus;
-	struct device *dev;
-
-	if (con->fwnode)
-		return device_connection_fwnode_match(con);
-
-	for (bus = generic_match_buses[0]; bus; bus++) {
-		dev = bus_find_device_by_name(bus, NULL, con->endpoint[ep]);
-		if (dev)
-			return dev;
-	}
-
-	/*
-	 * We only get called if a connection was found, tell the caller to
-	 * wait for the other device to show up.
-	 */
-	return ERR_PTR(-EPROBE_DEFER);
-}
-
-/**
- * device_connection_find - Find two devices connected together
- * @dev: Device with the connection
- * @con_id: Identifier for the connection
- *
- * Find a connection with unique identifier @con_id between @dev and
- * another device. On success returns handle to the device that is connected
- * to @dev, with the reference count for the found device incremented. Returns
- * NULL if no matching connection was found, or ERR_PTR(-EPROBE_DEFER) when a
- * connection was found but the other device has not been enumerated yet.
- */
-struct device *device_connection_find(struct device *dev, const char *con_id)
-{
-	return device_connection_find_match(dev, con_id, NULL, generic_match);
-}
-EXPORT_SYMBOL_GPL(device_connection_find);
-
-/**
- * device_connection_add - Register a connection description
- * @con: The connection description to be registered
- */
-void device_connection_add(struct device_connection *con)
-{
-	mutex_lock(&devcon_lock);
-	list_add_tail(&con->list, &devcon_list);
-	mutex_unlock(&devcon_lock);
-}
-EXPORT_SYMBOL_GPL(device_connection_add);
-
-/**
- * device_connections_remove - Unregister connection description
- * @con: The connection description to be unregistered
- */
-void device_connection_remove(struct device_connection *con)
-{
-	mutex_lock(&devcon_lock);
-	list_del(&con->list);
-	mutex_unlock(&devcon_lock);
-}
-EXPORT_SYMBOL_GPL(device_connection_remove);

drivers/base/devcoredump.c

@@ -123,7 +123,7 @@ static int devcd_free(struct device *dev, void *data)
 static ssize_t disabled_show(struct class *class, struct class_attribute *attr,
 			     char *buf)
 {
-	return sprintf(buf, "%d\n", devcd_disabled);
+	return sysfs_emit(buf, "%d\n", devcd_disabled);
 }
 
 static ssize_t disabled_store(struct class *class, struct class_attribute *attr,

drivers/base/devres.c

@@ -126,6 +126,14 @@ static void add_dr(struct device *dev, struct devres_node *node)
 	list_add_tail(&node->entry, &dev->devres_head);
 }
 
+static void replace_dr(struct device *dev,
+		       struct devres_node *old, struct devres_node *new)
+{
+	devres_log(dev, old, "REPLACE");
+	BUG_ON(!list_empty(&new->entry));
+	list_replace(&old->entry, &new->entry);
+}
+
 #ifdef CONFIG_DEBUG_DEVRES
 void * __devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp, int nid,
 		      const char *name)
@@ -837,6 +845,103 @@ void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp)
 }
 EXPORT_SYMBOL_GPL(devm_kmalloc);
 
+/**
+ * devm_krealloc - Resource-managed krealloc()
+ * @dev: Device to re-allocate memory for
+ * @ptr: Pointer to the memory chunk to re-allocate
+ * @new_size: New allocation size
+ * @gfp: Allocation gfp flags
+ *
+ * Managed krealloc(). Resizes the memory chunk allocated with devm_kmalloc().
+ * Behaves similarly to regular krealloc(): if @ptr is NULL or ZERO_SIZE_PTR,
+ * it's the equivalent of devm_kmalloc(). If new_size is zero, it frees the
+ * previously allocated memory and returns ZERO_SIZE_PTR. This function doesn't
+ * change the order in which the release callback for the re-alloc'ed devres
+ * will be called (except when falling back to devm_kmalloc() or when freeing
+ * resources when new_size is zero). The contents of the memory are preserved
+ * up to the lesser of new and old sizes.
+ */
+void *devm_krealloc(struct device *dev, void *ptr, size_t new_size, gfp_t gfp)
+{
+	size_t total_new_size, total_old_size;
+	struct devres *old_dr, *new_dr;
+	unsigned long flags;
+
+	if (unlikely(!new_size)) {
+		devm_kfree(dev, ptr);
+		return ZERO_SIZE_PTR;
+	}
+
+	if (unlikely(ZERO_OR_NULL_PTR(ptr)))
+		return devm_kmalloc(dev, new_size, gfp);
+
+	if (WARN_ON(is_kernel_rodata((unsigned long)ptr)))
+		/*
+		 * We cannot reliably realloc a const string returned by
+		 * devm_kstrdup_const().
+		 */
+		return NULL;
+
+	if (!check_dr_size(new_size, &total_new_size))
+		return NULL;
+
+	total_old_size = ksize(container_of(ptr, struct devres, data));
+	if (total_old_size == 0) {
+		WARN(1, "Pointer doesn't point to dynamically allocated memory.");
+		return NULL;
+	}
+
+	/*
+	 * If new size is smaller or equal to the actual number of bytes
+	 * allocated previously - just return the same pointer.
+	 */
+	if (total_new_size <= total_old_size)
+		return ptr;
+
+	/*
+	 * Otherwise: allocate new, larger chunk. We need to allocate before
+	 * taking the lock as most probably the caller uses GFP_KERNEL.
+	 */
+	new_dr = alloc_dr(devm_kmalloc_release,
+			  total_new_size, gfp, dev_to_node(dev));
+	if (!new_dr)
+		return NULL;
+
+	/*
+	 * The spinlock protects the linked list against concurrent
+	 * modifications but not the resource itself.
+	 */
+	spin_lock_irqsave(&dev->devres_lock, flags);
+
+	old_dr = find_dr(dev, devm_kmalloc_release, devm_kmalloc_match, ptr);
+	if (!old_dr) {
+		spin_unlock_irqrestore(&dev->devres_lock, flags);
+		kfree(new_dr);
+		WARN(1, "Memory chunk not managed or managed by a different device.");
+		return NULL;
+	}
+
+	replace_dr(dev, &old_dr->node, &new_dr->node);
+
+	spin_unlock_irqrestore(&dev->devres_lock, flags);
+
+	/*
+	 * We can copy the memory contents after releasing the lock as we're
+	 * no longer modyfing the list links.
+	 */
+	memcpy(new_dr->data, old_dr->data,
+	       total_old_size - offsetof(struct devres, data));
+	/*
+	 * Same for releasing the old devres - it's now been removed from the
+	 * list. This is also the reason why we must not use devm_kfree() - the
+	 * links are no longer valid.
+	 */
+	kfree(old_dr);
+
+	return new_dr->data;
+}
+EXPORT_SYMBOL_GPL(devm_krealloc);
+
 /**
  * devm_kstrdup - Allocate resource managed space and
  *                copy an existing string into that.

drivers/base/firmware_loader/fallback.c

@@ -124,7 +124,7 @@ void kill_pending_fw_fallback_reqs(bool only_kill_custom)
 static ssize_t timeout_show(struct class *class, struct class_attribute *attr,
 			    char *buf)
 {
-	return sprintf(buf, "%d\n", __firmware_loading_timeout());
+	return sysfs_emit(buf, "%d\n", __firmware_loading_timeout());
 }
 
 /**
@@ -219,7 +219,7 @@ static ssize_t firmware_loading_show(struct device *dev,
 		loading = fw_sysfs_loading(fw_sysfs->fw_priv);
 	mutex_unlock(&fw_lock);
 
-	return sprintf(buf, "%d\n", loading);
+	return sysfs_emit(buf, "%d\n", loading);
 }
 
 /**

drivers/base/memory.c

@@ -119,7 +119,8 @@ static ssize_t phys_index_show(struct device *dev,
 	unsigned long phys_index;
 
 	phys_index = mem->start_section_nr / sections_per_block;
-	return sprintf(buf, "%08lx\n", phys_index);
+
+	return sysfs_emit(buf, "%08lx\n", phys_index);
 }
 
 /*
@@ -129,7 +130,7 @@ static ssize_t phys_index_show(struct device *dev,
 static ssize_t removable_show(struct device *dev, struct device_attribute *attr,
 			      char *buf)
 {
-	return sprintf(buf, "%d\n", (int)IS_ENABLED(CONFIG_MEMORY_HOTREMOVE));
+	return sysfs_emit(buf, "%d\n", (int)IS_ENABLED(CONFIG_MEMORY_HOTREMOVE));
 }
 
 /*
@@ -139,7 +140,7 @@ static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 			  char *buf)
 {
 	struct memory_block *mem = to_memory_block(dev);
-	ssize_t len = 0;
+	const char *output;
 
 	/*
 	 * We can probably put these states in a nice little array
@@ -147,22 +148,20 @@ static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 	 */
 	switch (mem->state) {
 	case MEM_ONLINE:
-		len = sprintf(buf, "online\n");
+		output = "online";
 		break;
 	case MEM_OFFLINE:
-		len = sprintf(buf, "offline\n");
+		output = "offline";
 		break;
 	case MEM_GOING_OFFLINE:
-		len = sprintf(buf, "going-offline\n");
+		output = "going-offline";
 		break;
 	default:
-		len = sprintf(buf, "ERROR-UNKNOWN-%ld\n",
-				mem->state);
 		WARN_ON(1);
-		break;
+		return sysfs_emit(buf, "ERROR-UNKNOWN-%ld\n", mem->state);
 	}
 
-	return len;
+	return sysfs_emit(buf, "%s\n", output);
 }
 
 int memory_notify(unsigned long val, void *v)
@@ -303,21 +302,22 @@ static ssize_t phys_device_show(struct device *dev,
 				struct device_attribute *attr, char *buf)
 {
 	struct memory_block *mem = to_memory_block(dev);
-	return sprintf(buf, "%d\n", mem->phys_device);
+
+	return sysfs_emit(buf, "%d\n", mem->phys_device);
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
-static void print_allowed_zone(char *buf, int nid, unsigned long start_pfn,
-		unsigned long nr_pages, int online_type,
-		struct zone *default_zone)
+static int print_allowed_zone(char *buf, int len, int nid,
+			      unsigned long start_pfn, unsigned long nr_pages,
+			      int online_type, struct zone *default_zone)
 {
 	struct zone *zone;
 
 	zone = zone_for_pfn_range(online_type, nid, start_pfn, nr_pages);
-	if (zone != default_zone) {
-		strcat(buf, " ");
-		strcat(buf, zone->name);
-	}
+	if (zone == default_zone)
+		return 0;
+
+	return sysfs_emit_at(buf, len, " %s", zone->name);
 }
 
 static ssize_t valid_zones_show(struct device *dev,
@@ -327,6 +327,7 @@ static ssize_t valid_zones_show(struct device *dev,
 	unsigned long start_pfn = section_nr_to_pfn(mem->start_section_nr);
 	unsigned long nr_pages = PAGES_PER_SECTION * sections_per_block;
 	struct zone *default_zone;
+	int len = 0;
 	int nid;
 
 	/*
@@ -341,24 +342,23 @@ static ssize_t valid_zones_show(struct device *dev,
 		default_zone = test_pages_in_a_zone(start_pfn,
 						    start_pfn + nr_pages);
 		if (!default_zone)
-			return sprintf(buf, "none\n");
-		strcat(buf, default_zone->name);
+			return sysfs_emit(buf, "%s\n", "none");
+		len += sysfs_emit_at(buf, len, "%s", default_zone->name);
 		goto out;
 	}
 
 	nid = mem->nid;
 	default_zone = zone_for_pfn_range(MMOP_ONLINE, nid, start_pfn,
 					  nr_pages);
-	strcat(buf, default_zone->name);
 
-	print_allowed_zone(buf, nid, start_pfn, nr_pages, MMOP_ONLINE_KERNEL,
-			default_zone);
-	print_allowed_zone(buf, nid, start_pfn, nr_pages, MMOP_ONLINE_MOVABLE,
-			default_zone);
+	len += sysfs_emit_at(buf, len, "%s", default_zone->name);
+	len += print_allowed_zone(buf, len, nid, start_pfn, nr_pages,
+				  MMOP_ONLINE_KERNEL, default_zone);
+	len += print_allowed_zone(buf, len, nid, start_pfn, nr_pages,
+				  MMOP_ONLINE_MOVABLE, default_zone);
 out:
-	strcat(buf, "\n");
-
-	return strlen(buf);
+	len += sysfs_emit_at(buf, len, "\n");
+	return len;
 }
 static DEVICE_ATTR_RO(valid_zones);
 #endif
@@ -374,7 +374,7 @@ static DEVICE_ATTR_RO(removable);
 static ssize_t block_size_bytes_show(struct device *dev,
 				     struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%lx\n", memory_block_size_bytes());
+	return sysfs_emit(buf, "%lx\n", memory_block_size_bytes());
 }
 
 static DEVICE_ATTR_RO(block_size_bytes);
@@ -386,8 +386,8 @@ static DEVICE_ATTR_RO(block_size_bytes);
 static ssize_t auto_online_blocks_show(struct device *dev,
 				       struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%s\n",
-		       online_type_to_str[memhp_default_online_type]);
+	return sysfs_emit(buf, "%s\n",
+			  online_type_to_str[memhp_default_online_type]);
 }
 
 static ssize_t auto_online_blocks_store(struct device *dev,

drivers/base/platform.c

@@ -45,6 +45,8 @@ EXPORT_SYMBOL_GPL(platform_bus);
  * @dev: platform device
  * @type: resource type
  * @num: resource index
+ *
+ * Return: a pointer to the resource or NULL on failure.
  */
 struct resource *platform_get_resource(struct platform_device *dev,
 				       unsigned int type, unsigned int num)
@@ -70,6 +72,9 @@ EXPORT_SYMBOL_GPL(platform_get_resource);
  *        resource management
  * @index: resource index
  * @res: optional output parameter to store a pointer to the obtained resource.
+ *
+ * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
+ * on failure.
  */
 void __iomem *
 devm_platform_get_and_ioremap_resource(struct platform_device *pdev,
@@ -91,6 +96,9 @@ EXPORT_SYMBOL_GPL(devm_platform_get_and_ioremap_resource);
  * @pdev: platform device to use both for memory resource lookup as well as
  *        resource management
  * @index: resource index
+ *
+ * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
+ * on failure.
  */
 void __iomem *devm_platform_ioremap_resource(struct platform_device *pdev,
 					     unsigned int index)
@@ -106,6 +114,9 @@ EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource);
  * @pdev: platform device to use both for memory resource lookup as well as
  *        resource management
  * @index: resource index
+ *
+ * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
+ * on failure.
  */
 void __iomem *devm_platform_ioremap_resource_wc(struct platform_device *pdev,
 						unsigned int index)
@@ -124,6 +135,9 @@ void __iomem *devm_platform_ioremap_resource_wc(struct platform_device *pdev,
  * @pdev: platform device to use both for memory resource lookup as well as
  *	  resource management
  * @name: name of the resource
+ *
+ * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
+ * on failure.
  */
 void __iomem *
 devm_platform_ioremap_resource_byname(struct platform_device *pdev,
@@ -559,7 +573,7 @@ int platform_device_add(struct platform_device *pdev)
 		 * that we remember it must be freed, and we append a suffix
 		 * to avoid namespace collision with explicit IDs.
 		 */
-		ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
+		ret = ida_alloc(&platform_devid_ida, GFP_KERNEL);
 		if (ret < 0)
 			goto err_out;
 		pdev->id = ret;
@@ -600,7 +614,7 @@ int platform_device_add(struct platform_device *pdev)
 
  failed:
 	if (pdev->id_auto) {
-		ida_simple_remove(&platform_devid_ida, pdev->id);
+		ida_free(&platform_devid_ida, pdev->id);
 		pdev->id = PLATFORM_DEVID_AUTO;
 	}
 
@@ -631,7 +645,7 @@ void platform_device_del(struct platform_device *pdev)
 		device_del(&pdev->dev);
 
 		if (pdev->id_auto) {
-			ida_simple_remove(&platform_devid_ida, pdev->id);
+			ida_free(&platform_devid_ida, pdev->id);
 			pdev->id = PLATFORM_DEVID_AUTO;
 		}
 
@@ -1009,10 +1023,10 @@ EXPORT_SYMBOL_GPL(platform_unregister_drivers);
  * (b) sysfs attribute lets new-style coldplug recover from hotplug events
  *     mishandled before system is fully running:  "modprobe $(cat modalias)"
  */
-static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
-			     char *buf)
+static ssize_t modalias_show(struct device *dev,
+			     struct device_attribute *attr, char *buf)
 {
-	struct platform_device	*pdev = to_platform_device(dev);
+	struct platform_device *pdev = to_platform_device(dev);
 	int len;
 
 	len = of_device_modalias(dev, buf, PAGE_SIZE);
@@ -1023,9 +1037,7 @@ static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
 	if (len != -ENODEV)
 		return len;
 
-	len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
-
-	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
+	return sysfs_emit(buf, "platform:%s\n", pdev->name);
 }
 static DEVICE_ATTR_RO(modalias);
 
@@ -1070,16 +1082,17 @@ static ssize_t driver_override_show(struct device *dev,
 	ssize_t len;
 
 	device_lock(dev);
-	len = sprintf(buf, "%s\n", pdev->driver_override);
+	len = sysfs_emit(buf, "%s\n", pdev->driver_override);
 	device_unlock(dev);
+
 	return len;
 }
 static DEVICE_ATTR_RW(driver_override);
 
 static ssize_t numa_node_show(struct device *dev,
-		struct device_attribute *attr, char *buf)
+			      struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%d\n", dev_to_node(dev));
+	return sysfs_emit(buf, "%d\n", dev_to_node(dev));
 }
 static DEVICE_ATTR_RO(numa_node);
 

drivers/base/power/wakeup_stats.c

@@ -26,7 +26,7 @@ static ssize_t _name##_show(struct device *dev,				\
 {									\
 	struct wakeup_source *ws = dev_get_drvdata(dev);		\
 									\
-	return sprintf(buf, "%lu\n", ws->_name);			\
+	return sysfs_emit(buf, "%lu\n", ws->_name);			\
 }									\
 static DEVICE_ATTR_RO(_name)
 
@@ -42,7 +42,7 @@ static ssize_t active_time_ms_show(struct device *dev,
 	ktime_t active_time =
 		ws->active ? ktime_sub(ktime_get(), ws->last_time) : 0;
 
-	return sprintf(buf, "%lld\n", ktime_to_ms(active_time));
+	return sysfs_emit(buf, "%lld\n", ktime_to_ms(active_time));
 }
 static DEVICE_ATTR_RO(active_time_ms);
 
@@ -57,7 +57,8 @@ static ssize_t total_time_ms_show(struct device *dev,
 		active_time = ktime_sub(ktime_get(), ws->last_time);
 		total_time = ktime_add(total_time, active_time);
 	}
-	return sprintf(buf, "%lld\n", ktime_to_ms(total_time));
+
+	return sysfs_emit(buf, "%lld\n", ktime_to_ms(total_time));
 }
 static DEVICE_ATTR_RO(total_time_ms);
 
@@ -73,7 +74,8 @@ static ssize_t max_time_ms_show(struct device *dev,
 		if (active_time > max_time)
 			max_time = active_time;
 	}
-	return sprintf(buf, "%lld\n", ktime_to_ms(max_time));
+
+	return sysfs_emit(buf, "%lld\n", ktime_to_ms(max_time));
 }
 static DEVICE_ATTR_RO(max_time_ms);
 
@@ -82,7 +84,7 @@ static ssize_t last_change_ms_show(struct device *dev,
 {
 	struct wakeup_source *ws = dev_get_drvdata(dev);
 
-	return sprintf(buf, "%lld\n", ktime_to_ms(ws->last_time));
+	return sysfs_emit(buf, "%lld\n", ktime_to_ms(ws->last_time));
 }
 static DEVICE_ATTR_RO(last_change_ms);
 
@@ -91,7 +93,7 @@ static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 {
 	struct wakeup_source *ws = dev_get_drvdata(dev);
 
-	return sprintf(buf, "%s\n", ws->name);
+	return sysfs_emit(buf, "%s\n", ws->name);
 }
 static DEVICE_ATTR_RO(name);
 
@@ -106,7 +108,8 @@ static ssize_t prevent_suspend_time_ms_show(struct device *dev,
 		prevent_sleep_time = ktime_add(prevent_sleep_time,
 			ktime_sub(ktime_get(), ws->start_prevent_time));
 	}
-	return sprintf(buf, "%lld\n", ktime_to_ms(prevent_sleep_time));
+
+	return sysfs_emit(buf, "%lld\n", ktime_to_ms(prevent_sleep_time));
 }
 static DEVICE_ATTR_RO(prevent_suspend_time_ms);
 

drivers/base/property.c

@@ -1184,3 +1184,76 @@ const void *device_get_match_data(struct device *dev)
 	return fwnode_call_ptr_op(dev_fwnode(dev), device_get_match_data, dev);
 }
 EXPORT_SYMBOL_GPL(device_get_match_data);
+
+static void *
+fwnode_graph_devcon_match(struct fwnode_handle *fwnode, const char *con_id,
+			  void *data, devcon_match_fn_t match)
+{
+	struct fwnode_handle *node;
+	struct fwnode_handle *ep;
+	void *ret;
+
+	fwnode_graph_for_each_endpoint(fwnode, ep) {
+		node = fwnode_graph_get_remote_port_parent(ep);
+		if (!fwnode_device_is_available(node))
+			continue;
+
+		ret = match(node, con_id, data);
+		fwnode_handle_put(node);
+		if (ret) {
+			fwnode_handle_put(ep);
+			return ret;
+		}
+	}
+	return NULL;
+}
+
+static void *
+fwnode_devcon_match(struct fwnode_handle *fwnode, const char *con_id,
+		    void *data, devcon_match_fn_t match)
+{
+	struct fwnode_handle *node;
+	void *ret;
+	int i;
+
+	for (i = 0; ; i++) {
+		node = fwnode_find_reference(fwnode, con_id, i);
+		if (IS_ERR(node))
+			break;
+
+		ret = match(node, NULL, data);
+		fwnode_handle_put(node);
+		if (ret)
+			return ret;
+	}
+
+	return NULL;
+}
+
+/**
+ * fwnode_connection_find_match - Find connection from a device node
+ * @fwnode: Device node with the connection
+ * @con_id: Identifier for the connection
+ * @data: Data for the match function
+ * @match: Function to check and convert the connection description
+ *
+ * Find a connection with unique identifier @con_id between @fwnode and another
+ * device node. @match will be used to convert the connection description to
+ * data the caller is expecting to be returned.
+ */
+void *fwnode_connection_find_match(struct fwnode_handle *fwnode,
+				   const char *con_id, void *data,
+				   devcon_match_fn_t match)
+{
+	void *ret;
+
+	if (!fwnode || !match)
+		return NULL;
+
+	ret = fwnode_graph_devcon_match(fwnode, con_id, data, match);
+	if (ret)
+		return ret;
+
+	return fwnode_devcon_match(fwnode, con_id, data, match);
+}
+EXPORT_SYMBOL_GPL(fwnode_connection_find_match);

drivers/base/soc.c

@@ -17,9 +17,9 @@
 
 static DEFINE_IDA(soc_ida);
 
-static ssize_t soc_info_get(struct device *dev,
-			    struct device_attribute *attr,
-			    char *buf);
+/* Prototype to allow declarations of DEVICE_ATTR(<foo>) before soc_info_show */
+static ssize_t soc_info_show(struct device *dev, struct device_attribute *attr,
+			     char *buf);
 
 struct soc_device {
 	struct device dev;
@@ -31,11 +31,11 @@ static struct bus_type soc_bus_type = {
 	.name  = "soc",
 };
 
-static DEVICE_ATTR(machine,  S_IRUGO, soc_info_get,  NULL);
-static DEVICE_ATTR(family,   S_IRUGO, soc_info_get,  NULL);
-static DEVICE_ATTR(serial_number, S_IRUGO, soc_info_get,  NULL);
-static DEVICE_ATTR(soc_id,   S_IRUGO, soc_info_get,  NULL);
-static DEVICE_ATTR(revision, S_IRUGO, soc_info_get,  NULL);
+static DEVICE_ATTR(machine,		0444, soc_info_show,  NULL);
+static DEVICE_ATTR(family,		0444, soc_info_show,  NULL);
+static DEVICE_ATTR(serial_number,	0444, soc_info_show,  NULL);
+static DEVICE_ATTR(soc_id,		0444, soc_info_show,  NULL);
+static DEVICE_ATTR(revision,		0444, soc_info_show,  NULL);
 
 struct device *soc_device_to_device(struct soc_device *soc_dev)
 {
@@ -49,45 +49,41 @@ static umode_t soc_attribute_mode(struct kobject *kobj,
 	struct device *dev = kobj_to_dev(kobj);
 	struct soc_device *soc_dev = container_of(dev, struct soc_device, dev);
 
-	if ((attr == &dev_attr_machine.attr)
-	    && (soc_dev->attr->machine != NULL))
+	if ((attr == &dev_attr_machine.attr) && soc_dev->attr->machine)
 		return attr->mode;
-	if ((attr == &dev_attr_family.attr)
-	    && (soc_dev->attr->family != NULL))
+	if ((attr == &dev_attr_family.attr) && soc_dev->attr->family)
 		return attr->mode;
-	if ((attr == &dev_attr_revision.attr)
-	    && (soc_dev->attr->revision != NULL))
+	if ((attr == &dev_attr_revision.attr) && soc_dev->attr->revision)
 		return attr->mode;
-	if ((attr == &dev_attr_serial_number.attr)
-	    && (soc_dev->attr->serial_number != NULL))
+	if ((attr == &dev_attr_serial_number.attr) && soc_dev->attr->serial_number)
 		return attr->mode;
-	if ((attr == &dev_attr_soc_id.attr)
-	    && (soc_dev->attr->soc_id != NULL))
+	if ((attr == &dev_attr_soc_id.attr) && soc_dev->attr->soc_id)
 		return attr->mode;
 
-	/* Unknown or unfilled attribute. */
+	/* Unknown or unfilled attribute */
 	return 0;
 }
 
-static ssize_t soc_info_get(struct device *dev,
-			    struct device_attribute *attr,
-			    char *buf)
+static ssize_t soc_info_show(struct device *dev, struct device_attribute *attr,
+			     char *buf)
 {
 	struct soc_device *soc_dev = container_of(dev, struct soc_device, dev);
+	const char *output;
 
 	if (attr == &dev_attr_machine)
-		return sprintf(buf, "%s\n", soc_dev->attr->machine);
-	if (attr == &dev_attr_family)
-		return sprintf(buf, "%s\n", soc_dev->attr->family);
-	if (attr == &dev_attr_revision)
-		return sprintf(buf, "%s\n", soc_dev->attr->revision);
-	if (attr == &dev_attr_serial_number)
-		return sprintf(buf, "%s\n", soc_dev->attr->serial_number);
-	if (attr == &dev_attr_soc_id)
-		return sprintf(buf, "%s\n", soc_dev->attr->soc_id);
-
-	return -EINVAL;
-
+		output = soc_dev->attr->machine;
+	else if (attr == &dev_attr_family)
+		output = soc_dev->attr->family;
+	else if (attr == &dev_attr_revision)
+		output = soc_dev->attr->revision;
+	else if (attr == &dev_attr_serial_number)
+		output = soc_dev->attr->serial_number;
+	else if (attr == &dev_attr_soc_id)
+		output = soc_dev->attr->soc_id;
+	else
+		return -EINVAL;
+
+	return sysfs_emit(buf, "%s\n", output);
 }
 
 static struct attribute *soc_attr[] = {

drivers/base/syscore.c

@@ -50,7 +50,7 @@ int syscore_suspend(void)
 	int ret = 0;
 
 	trace_suspend_resume(TPS("syscore_suspend"), 0, true);
-	pr_debug("Checking wakeup interrupts\n");
+	pm_pr_dbg("Checking wakeup interrupts\n");
 
 	/* Return error code if there are any wakeup interrupts pending. */
 	if (pm_wakeup_pending())
@@ -61,8 +61,7 @@ int syscore_suspend(void)
 
 	list_for_each_entry_reverse(ops, &syscore_ops_list, node)
 		if (ops->suspend) {
-			if (initcall_debug)
-				pr_info("PM: Calling %pS\n", ops->suspend);
+			pm_pr_dbg("Calling %pS\n", ops->suspend);
 			ret = ops->suspend();
 			if (ret)
 				goto err_out;
@@ -99,8 +98,7 @@ void syscore_resume(void)
 
 	list_for_each_entry(ops, &syscore_ops_list, node)
 		if (ops->resume) {
-			if (initcall_debug)
-				pr_info("PM: Calling %pS\n", ops->resume);
+			pm_pr_dbg("Calling %pS\n", ops->resume);
 			ops->resume();
 			WARN_ONCE(!irqs_disabled(),
 				"Interrupts enabled after %pS\n", ops->resume);

drivers/base/topology.c

@@ -14,11 +14,11 @@
 #include <linux/hardirq.h>
 #include <linux/topology.h>
 
-#define define_id_show_func(name)				\
-static ssize_t name##_show(struct device *dev,			\
-		struct device_attribute *attr, char *buf)	\
-{								\
-	return sprintf(buf, "%d\n", topology_##name(dev->id));	\
+#define define_id_show_func(name)					\
+static ssize_t name##_show(struct device *dev,				\
+			   struct device_attribute *attr, char *buf)	\
+{									\
+	return sysfs_emit(buf, "%d\n", topology_##name(dev->id));	\
 }
 
 #define define_siblings_show_map(name, mask)				\

drivers/hwmon/pmbus/pmbus_core.c

@@ -987,9 +987,9 @@ static int pmbus_add_attribute(struct pmbus_data *data, struct attribute *attr)
 {
 	if (data->num_attributes >= data->max_attributes - 1) {
 		int new_max_attrs = data->max_attributes + PMBUS_ATTR_ALLOC_SIZE;
-		void *new_attrs = krealloc(data->group.attrs,
-					   new_max_attrs * sizeof(void *),
-					   GFP_KERNEL);
+		void *new_attrs = devm_krealloc(data->dev, data->group.attrs,
+						new_max_attrs * sizeof(void *),
+						GFP_KERNEL);
 		if (!new_attrs)
 			return -ENOMEM;
 		data->group.attrs = new_attrs;
@@ -2578,7 +2578,7 @@ int pmbus_do_probe(struct i2c_client *client, struct pmbus_driver_info *info)
 
 	ret = pmbus_find_attributes(client, data);
 	if (ret)
-		goto out_kfree;
+		return ret;
 
 	/*
 	 * If there are no attributes, something is wrong.
@@ -2586,35 +2586,27 @@ int pmbus_do_probe(struct i2c_client *client, struct pmbus_driver_info *info)
 	 */
 	if (!data->num_attributes) {
 		dev_err(dev, "No attributes found\n");
-		ret = -ENODEV;
-		goto out_kfree;
+		return -ENODEV;
 	}
 
 	data->groups[0] = &data->group;
 	memcpy(data->groups + 1, info->groups, sizeof(void *) * groups_num);
-	data->hwmon_dev = hwmon_device_register_with_groups(dev, client->name,
-							    data, data->groups);
+	data->hwmon_dev = devm_hwmon_device_register_with_groups(dev,
+					client->name, data, data->groups);
 	if (IS_ERR(data->hwmon_dev)) {
-		ret = PTR_ERR(data->hwmon_dev);
 		dev_err(dev, "Failed to register hwmon device\n");
-		goto out_kfree;
+		return PTR_ERR(data->hwmon_dev);
 	}
 
 	ret = pmbus_regulator_register(data);
 	if (ret)
-		goto out_unregister;
+		return ret;
 
 	ret = pmbus_init_debugfs(client, data);
 	if (ret)
 		dev_warn(dev, "Failed to register debugfs\n");
 
 	return 0;
-
-out_unregister:
-	hwmon_device_unregister(data->hwmon_dev);
-out_kfree:
-	kfree(data->group.attrs);
-	return ret;
 }
 EXPORT_SYMBOL_GPL(pmbus_do_probe);
 
@@ -2624,8 +2616,6 @@ int pmbus_do_remove(struct i2c_client *client)
 
 	debugfs_remove_recursive(data->debugfs);
 
-	hwmon_device_unregister(data->hwmon_dev);
-	kfree(data->group.attrs);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(pmbus_do_remove);

drivers/iio/adc/xilinx-xadc-core.c

@@ -1092,6 +1092,7 @@ MODULE_DEVICE_TABLE(of, xadc_of_match_table);
 static int xadc_parse_dt(struct iio_dev *indio_dev, struct device_node *np,
 	unsigned int *conf)
 {
+	struct device *dev = indio_dev->dev.parent;
 	struct xadc *xadc = iio_priv(indio_dev);
 	struct iio_chan_spec *channels, *chan;
 	struct device_node *chan_node, *child;
@@ -1136,7 +1137,8 @@ static int xadc_parse_dt(struct iio_dev *indio_dev, struct device_node *np,
 		*conf |= XADC_CONF0_MUX | XADC_CONF0_CHAN(ext_mux_chan);
 	}
 
-	channels = kmemdup(xadc_channels, sizeof(xadc_channels), GFP_KERNEL);
+	channels = devm_kmemdup(dev, xadc_channels,
+				sizeof(xadc_channels), GFP_KERNEL);
 	if (!channels)
 		return -ENOMEM;
 
@@ -1172,8 +1174,9 @@ static int xadc_parse_dt(struct iio_dev *indio_dev, struct device_node *np,
 	of_node_put(chan_node);
 
 	indio_dev->num_channels = num_channels;
-	indio_dev->channels = krealloc(channels, sizeof(*channels) *
-					num_channels, GFP_KERNEL);
+	indio_dev->channels = devm_krealloc(dev, channels,
+					    sizeof(*channels) * num_channels,
+					    GFP_KERNEL);
 	/* If we can't resize the channels array, just use the original */
 	if (!indio_dev->channels)
 		indio_dev->channels = channels;
@@ -1225,14 +1228,14 @@ static int xadc_probe(struct platform_device *pdev)
 
 	ret = xadc_parse_dt(indio_dev, pdev->dev.of_node, &conf0);
 	if (ret)
-		goto err_device_free;
+		return ret;
 
 	if (xadc->ops->flags & XADC_FLAGS_BUFFERED) {
 		ret = iio_triggered_buffer_setup(indio_dev,
 			&iio_pollfunc_store_time, &xadc_trigger_handler,
 			&xadc_buffer_ops);
 		if (ret)
-			goto err_device_free;
+			return ret;
 
 		xadc->convst_trigger = xadc_alloc_trigger(indio_dev, "convst");
 		if (IS_ERR(xadc->convst_trigger)) {
@@ -1350,8 +1353,6 @@ static int xadc_probe(struct platform_device *pdev)
 err_triggered_buffer_cleanup:
 	if (xadc->ops->flags & XADC_FLAGS_BUFFERED)
 		iio_triggered_buffer_cleanup(indio_dev);
-err_device_free:
-	kfree(indio_dev->channels);
 
 	return ret;
 }
@@ -1371,7 +1372,6 @@ static int xadc_remove(struct platform_device *pdev)
 	cancel_delayed_work_sync(&xadc->zynq_unmask_work);
 	clk_disable_unprepare(xadc->clk);
 	kfree(xadc->data);
-	kfree(indio_dev->channels);
 
 	return 0;
 }

drivers/usb/roles/class.c

@@ -87,19 +87,15 @@ enum usb_role usb_role_switch_get_role(struct usb_role_switch *sw)
 }
 EXPORT_SYMBOL_GPL(usb_role_switch_get_role);
 
-static void *usb_role_switch_match(struct device_connection *con, int ep,
+static void *usb_role_switch_match(struct fwnode_handle *fwnode, const char *id,
 				   void *data)
 {
 	struct device *dev;
 
-	if (con->fwnode) {
-		if (con->id && !fwnode_property_present(con->fwnode, con->id))
-			return NULL;
+	if (id && !fwnode_property_present(fwnode, id))
+		return NULL;
 
-		dev = class_find_device_by_fwnode(role_class, con->fwnode);
-	} else {
-		dev = class_find_device_by_name(role_class, con->endpoint[ep]);
-	}
+	dev = class_find_device_by_fwnode(role_class, fwnode);
 
 	return dev ? to_role_switch(dev) : ERR_PTR(-EPROBE_DEFER);
 }

drivers/usb/typec/mux.c

@@ -34,15 +34,15 @@ static int switch_fwnode_match(struct device *dev, const void *fwnode)
 	return dev_fwnode(dev) == fwnode && dev_name_ends_with(dev, "-switch");
 }
 
-static void *typec_switch_match(struct device_connection *con, int ep,
+static void *typec_switch_match(struct fwnode_handle *fwnode, const char *id,
 				void *data)
 {
 	struct device *dev;
 
-	if (con->id && !fwnode_property_present(con->fwnode, con->id))
+	if (id && !fwnode_property_present(fwnode, id))
 		return NULL;
 
-	dev = class_find_device(&typec_mux_class, NULL, con->fwnode,
+	dev = class_find_device(&typec_mux_class, NULL, fwnode,
 				switch_fwnode_match);
 
 	return dev ? to_typec_switch(dev) : ERR_PTR(-EPROBE_DEFER);
@@ -183,7 +183,8 @@ static int mux_fwnode_match(struct device *dev, const void *fwnode)
 	return dev_fwnode(dev) == fwnode && dev_name_ends_with(dev, "-mux");
 }
 
-static void *typec_mux_match(struct device_connection *con, int ep, void *data)
+static void *typec_mux_match(struct fwnode_handle *fwnode, const char *id,
+			     void *data)
 {
 	const struct typec_altmode_desc *desc = data;
 	struct device *dev;
@@ -196,20 +197,20 @@ static void *typec_mux_match(struct device_connection *con, int ep, void *data)
 	 * Check has the identifier already been "consumed". If it
 	 * has, no need to do any extra connection identification.
 	 */
-	match = !con->id;
+	match = !id;
 	if (match)
 		goto find_mux;
 
 	/* Accessory Mode muxes */
 	if (!desc) {
-		match = fwnode_property_present(con->fwnode, "accessory");
+		match = fwnode_property_present(fwnode, "accessory");
 		if (match)
 			goto find_mux;
 		return NULL;
 	}
 
 	/* Alternate Mode muxes */
-	nval = fwnode_property_count_u16(con->fwnode, "svid");
+	nval = fwnode_property_count_u16(fwnode, "svid");
 	if (nval <= 0)
 		return NULL;
 
@@ -217,7 +218,7 @@ static void *typec_mux_match(struct device_connection *con, int ep, void *data)
 	if (!val)
 		return ERR_PTR(-ENOMEM);
 
-	nval = fwnode_property_read_u16_array(con->fwnode, "svid", val, nval);
+	nval = fwnode_property_read_u16_array(fwnode, "svid", val, nval);
 	if (nval < 0) {
 		kfree(val);
 		return ERR_PTR(nval);
@@ -234,7 +235,7 @@ static void *typec_mux_match(struct device_connection *con, int ep, void *data)
 	return NULL;
 
 find_mux:
-	dev = class_find_device(&typec_mux_class, NULL, con->fwnode,
+	dev = class_find_device(&typec_mux_class, NULL, fwnode,
 				mux_fwnode_match);
 
 	return dev ? to_typec_switch(dev) : ERR_PTR(-EPROBE_DEFER);

fs/sysfs/file.c

@@ -15,6 +15,7 @@
 #include <linux/list.h>
 #include <linux/mutex.h>
 #include <linux/seq_file.h>
+#include <linux/mm.h>
 
 #include "sysfs.h"
 
@@ -707,3 +708,57 @@ int sysfs_change_owner(struct kobject *kobj, kuid_t kuid, kgid_t kgid)
 	return 0;
 }
 EXPORT_SYMBOL_GPL(sysfs_change_owner);
+
+/**
+ *	sysfs_emit - scnprintf equivalent, aware of PAGE_SIZE buffer.
+ *	@buf:	start of PAGE_SIZE buffer.
+ *	@fmt:	format
+ *	@...:	optional arguments to @format
+ *
+ *
+ * Returns number of characters written to @buf.
+ */
+int sysfs_emit(char *buf, const char *fmt, ...)
+{
+	va_list args;
+	int len;
+
+	if (WARN(!buf || offset_in_page(buf),
+		 "invalid sysfs_emit: buf:%p\n", buf))
+		return 0;
+
+	va_start(args, fmt);
+	len = vscnprintf(buf, PAGE_SIZE, fmt, args);
+	va_end(args);
+
+	return len;
+}
+EXPORT_SYMBOL_GPL(sysfs_emit);
+
+/**
+ *	sysfs_emit_at - scnprintf equivalent, aware of PAGE_SIZE buffer.
+ *	@buf:	start of PAGE_SIZE buffer.
+ *	@at:	offset in @buf to start write in bytes
+ *		@at must be >= 0 && < PAGE_SIZE
+ *	@fmt:	format
+ *	@...:	optional arguments to @fmt
+ *
+ *
+ * Returns number of characters written starting at &@buf[@at].
+ */
+int sysfs_emit_at(char *buf, int at, const char *fmt, ...)
+{
+	va_list args;
+	int len;
+
+	if (WARN(!buf || offset_in_page(buf) || at < 0 || at >= PAGE_SIZE,
+		 "invalid sysfs_emit_at: buf:%p at:%d\n", buf, at))
+		return 0;
+
+	va_start(args, fmt);
+	len = vscnprintf(buf + at, PAGE_SIZE - at, fmt, args);
+	va_end(args);
+
+	return len;
+}
+EXPORT_SYMBOL_GPL(sysfs_emit_at);

include/linux/device.h

@@ -206,6 +206,8 @@ int devres_release_group(struct device *dev, void *id);
 
 /* managed devm_k.alloc/kfree for device drivers */
 void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) __malloc;
+void *devm_krealloc(struct device *dev, void *ptr, size_t size,
+		    gfp_t gfp) __must_check;
 __printf(3, 0) char *devm_kvasprintf(struct device *dev, gfp_t gfp,
 				     const char *fmt, va_list ap) __malloc;
 __printf(3, 4) char *devm_kasprintf(struct device *dev, gfp_t gfp,
@@ -292,62 +294,6 @@ struct device_dma_parameters {
 	unsigned long segment_boundary_mask;
 };
 
-/**
- * struct device_connection - Device Connection Descriptor
- * @fwnode: The device node of the connected device
- * @endpoint: The names of the two devices connected together
- * @id: Unique identifier for the connection
- * @list: List head, private, for internal use only
- *
- * NOTE: @fwnode is not used together with @endpoint. @fwnode is used when
- * platform firmware defines the connection. When the connection is registered
- * with device_connection_add() @endpoint is used instead.
- */
-struct device_connection {
-	struct fwnode_handle	*fwnode;
-	const char		*endpoint[2];
-	const char		*id;
-	struct list_head	list;
-};
-
-typedef void *(*devcon_match_fn_t)(struct device_connection *con, int ep,
-				   void *data);
-
-void *fwnode_connection_find_match(struct fwnode_handle *fwnode,
-				   const char *con_id, void *data,
-				   devcon_match_fn_t match);
-void *device_connection_find_match(struct device *dev, const char *con_id,
-				   void *data, devcon_match_fn_t match);
-
-struct device *device_connection_find(struct device *dev, const char *con_id);
-
-void device_connection_add(struct device_connection *con);
-void device_connection_remove(struct device_connection *con);
-
-/**
- * device_connections_add - Add multiple device connections at once
- * @cons: Zero terminated array of device connection descriptors
- */
-static inline void device_connections_add(struct device_connection *cons)
-{
-	struct device_connection *c;
-
-	for (c = cons; c->endpoint[0]; c++)
-		device_connection_add(c);
-}
-
-/**
- * device_connections_remove - Remove multiple device connections at once
- * @cons: Zero terminated array of device connection descriptors
- */
-static inline void device_connections_remove(struct device_connection *cons)
-{
-	struct device_connection *c;
-
-	for (c = cons; c->endpoint[0]; c++)
-		device_connection_remove(c);
-}
-
 /**
  * enum device_link_state - Device link states.
  * @DL_STATE_NONE: The presence of the drivers is not being tracked.

include/linux/hugetlb.h

@@ -129,7 +129,7 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
 				unsigned long start, unsigned long end,
 				struct page *ref_page);
 void hugetlb_report_meminfo(struct seq_file *);
-int hugetlb_report_node_meminfo(int, char *);
+int hugetlb_report_node_meminfo(char *buf, int len, int nid);
 void hugetlb_show_meminfo(void);
 unsigned long hugetlb_total_pages(void);
 vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
@@ -245,7 +245,7 @@ static inline void hugetlb_report_meminfo(struct seq_file *m)
 {
 }
 
-static inline int hugetlb_report_node_meminfo(int nid, char *buf)
+static inline int hugetlb_report_node_meminfo(char *buf, int len, int nid)
 {
 	return 0;
 }

include/linux/property.h

@@ -431,6 +431,20 @@ fwnode_graph_get_endpoint_by_id(const struct fwnode_handle *fwnode,
 int fwnode_graph_parse_endpoint(const struct fwnode_handle *fwnode,
 				struct fwnode_endpoint *endpoint);
 
+typedef void *(*devcon_match_fn_t)(struct fwnode_handle *fwnode, const char *id,
+				   void *data);
+
+void *fwnode_connection_find_match(struct fwnode_handle *fwnode,
+				   const char *con_id, void *data,
+				   devcon_match_fn_t match);
+
+static inline void *device_connection_find_match(struct device *dev,
+						 const char *con_id, void *data,
+						 devcon_match_fn_t match)
+{
+	return fwnode_connection_find_match(dev_fwnode(dev), con_id, data, match);
+}
+
 /* -------------------------------------------------------------------------- */
 /* Software fwnode support - when HW description is incomplete or missing */
 

include/linux/sysfs.h

@@ -329,6 +329,10 @@ int sysfs_groups_change_owner(struct kobject *kobj,
 int sysfs_group_change_owner(struct kobject *kobj,
 			     const struct attribute_group *groups, kuid_t kuid,
 			     kgid_t kgid);
+__printf(2, 3)
+int sysfs_emit(char *buf, const char *fmt, ...);
+__printf(3, 4)
+int sysfs_emit_at(char *buf, int at, const char *fmt, ...);
 
 #else /* CONFIG_SYSFS */
 
@@ -576,6 +580,17 @@ static inline int sysfs_group_change_owner(struct kobject *kobj,
 	return 0;
 }
 
+__printf(2, 3)
+static inline int sysfs_emit(char *buf, const char *fmt, ...)
+{
+	return 0;
+}
+
+__printf(3, 4)
+static inline int sysfs_emit_at(char *buf, int at, const char *fmt, ...)
+{
+	return 0;
+}
 #endif /* CONFIG_SYSFS */
 
 static inline int __must_check sysfs_create_file(struct kobject *kobj,

lib/devres.c

@@ -162,13 +162,15 @@ __devm_ioremap_resource(struct device *dev, const struct resource *res,
  * region and ioremaps it. All operations are managed and will be undone
  * on driver detach.
  *
- * Returns a pointer to the remapped memory or an ERR_PTR() encoded error code
- * on failure. Usage example:
+ * Usage example:
  *
  *	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  *	base = devm_ioremap_resource(&pdev->dev, res);
  *	if (IS_ERR(base))
  *		return PTR_ERR(base);
+ *
+ * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
+ * on failure.
  */
 void __iomem *devm_ioremap_resource(struct device *dev,
 				    const struct resource *res)
@@ -183,8 +185,8 @@ EXPORT_SYMBOL(devm_ioremap_resource);
  * @dev: generic device to handle the resource for
  * @res: resource to be handled
  *
- * Returns a pointer to the remapped memory or an ERR_PTR() encoded error code
- * on failure. Usage example:
+ * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
+ * on failure.
  */
 void __iomem *devm_ioremap_resource_wc(struct device *dev,
 				       const struct resource *res)
@@ -207,8 +209,8 @@ void __iomem *devm_ioremap_resource_wc(struct device *dev,
  * @node:       The device-tree node where the resource resides
  * @index:	index of the MMIO range in the "reg" property
  * @size:	Returns the size of the resource (pass NULL if not needed)
- * Returns a pointer to the requested and mapped memory or an ERR_PTR() encoded
- * error code on failure. Usage example:
+ *
+ * Usage example:
  *
  *	base = devm_of_iomap(&pdev->dev, node, 0, NULL);
  *	if (IS_ERR(base))
@@ -217,8 +219,10 @@ void __iomem *devm_ioremap_resource_wc(struct device *dev,
  * Please Note: This is not a one-to-one replacement for of_iomap() because the
  * of_iomap() function does not track whether the region is already mapped.  If
  * two drivers try to map the same memory, the of_iomap() function will succeed
- * but the the devm_of_iomap() function will return -EBUSY.
+ * but the devm_of_iomap() function will return -EBUSY.
  *
+ * Return: a pointer to the requested and mapped memory or an ERR_PTR() encoded
+ * error code on failure.
  */
 void __iomem *devm_of_iomap(struct device *dev, struct device_node *node, int index,
 			    resource_size_t *size)
@@ -256,6 +260,8 @@ static int devm_ioport_map_match(struct device *dev, void *res,
  *
  * Managed ioport_map().  Map is automatically unmapped on driver
  * detach.
+ *
+ * Return: a pointer to the remapped memory or NULL on failure.
  */
 void __iomem *devm_ioport_map(struct device *dev, unsigned long port,
 			       unsigned int nr)

lib/dynamic_debug.c

@@ -384,10 +384,13 @@ static int ddebug_parse_query(char *words[], int nwords,
 		query->module = modname;
 
 	for (i = 0; i < nwords; i += 2) {
-		if (!strcmp(words[i], "func")) {
-			rc = check_set(&query->function, words[i+1], "func");
-		} else if (!strcmp(words[i], "file")) {
-			if (check_set(&query->filename, words[i+1], "file"))
+		char *keyword = words[i];
+		char *arg = words[i+1];
+
+		if (!strcmp(keyword, "func")) {
+			rc = check_set(&query->function, arg, "func");
+		} else if (!strcmp(keyword, "file")) {
+			if (check_set(&query->filename, arg, "file"))
 				return -EINVAL;
 
 			/* tail :$info is function or line-range */
@@ -403,18 +406,18 @@ static int ddebug_parse_query(char *words[], int nwords,
 				if (parse_linerange(query, fline))
 					return -EINVAL;
 			}
-		} else if (!strcmp(words[i], "module")) {
-			rc = check_set(&query->module, words[i+1], "module");
-		} else if (!strcmp(words[i], "format")) {
-			string_unescape_inplace(words[i+1], UNESCAPE_SPACE |
+		} else if (!strcmp(keyword, "module")) {
+			rc = check_set(&query->module, arg, "module");
+		} else if (!strcmp(keyword, "format")) {
+			string_unescape_inplace(arg, UNESCAPE_SPACE |
 							    UNESCAPE_OCTAL |
 							    UNESCAPE_SPECIAL);
-			rc = check_set(&query->format, words[i+1], "format");
-		} else if (!strcmp(words[i], "line")) {
-			if (parse_linerange(query, words[i+1]))
+			rc = check_set(&query->format, arg, "format");
+		} else if (!strcmp(keyword, "line")) {
+			if (parse_linerange(query, arg))
 				return -EINVAL;
 		} else {
-			pr_err("unknown keyword \"%s\"\n", words[i]);
+			pr_err("unknown keyword \"%s\"\n", keyword);
 			return -EINVAL;
 		}
 		if (rc)

mm/hugetlb.c

@@ -3571,18 +3571,20 @@ void hugetlb_report_meminfo(struct seq_file *m)
 	seq_printf(m, "Hugetlb:        %8lu kB\n", total / 1024);
 }
 
-int hugetlb_report_node_meminfo(int nid, char *buf)
+int hugetlb_report_node_meminfo(char *buf, int len, int nid)
 {
 	struct hstate *h = &default_hstate;
+
 	if (!hugepages_supported())
 		return 0;
-	return sprintf(buf,
-		"Node %d HugePages_Total: %5u\n"
-		"Node %d HugePages_Free:  %5u\n"
-		"Node %d HugePages_Surp:  %5u\n",
-		nid, h->nr_huge_pages_node[nid],
-		nid, h->free_huge_pages_node[nid],
-		nid, h->surplus_huge_pages_node[nid]);
+
+	return sysfs_emit_at(buf, len,
+			     "Node %d HugePages_Total: %5u\n"
+			     "Node %d HugePages_Free:  %5u\n"
+			     "Node %d HugePages_Surp:  %5u\n",
+			     nid, h->nr_huge_pages_node[nid],
+			     nid, h->free_huge_pages_node[nid],
+			     nid, h->surplus_huge_pages_node[nid]);
 }
 
 void hugetlb_show_meminfo(void)

scripts/dev-needs.sh

+#! /bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2020, Google LLC. All rights reserved.
+# Author: Saravana Kannan <saravanak@google.com>
+
+function help() {
+	cat << EOF
+Usage: $(basename $0) [-c|-d|-m|-f] [filter options] <list of devices>
+
+This script needs to be run on the target device once it has booted to a
+shell.
+
+The script takes as input a list of one or more device directories under
+/sys/devices and then lists the probe dependency chain (suppliers and
+parents) of these devices. It does a breadth first search of the dependency
+chain, so the last entry in the output is close to the root of the
+dependency chain.
+
+By default it lists the full path to the devices under /sys/devices.
+
+It also takes an optional modifier flag as the first parameter to change
+what information is listed in the output. If the requested information is
+not available, the device name is printed.
+
+  -c	lists the compatible string of the dependencies
+  -d	lists the driver name of the dependencies that have probed
+  -m	lists the module name of the dependencies that have a module
+  -f	list the firmware node path of the dependencies
+  -g	list the dependencies as edges and nodes for graphviz
+  -t	list the dependencies as edges for tsort
+
+The filter options provide a way to filter out some dependencies:
+  --allow-no-driver	By default dependencies that don't have a driver
+			attached are ignored. This is to avoid following
+			device links to "class" devices that are created
+			when the consumer probes (as in, not a probe
+			dependency). If you want to follow these links
+			anyway, use this flag.
+
+  --exclude-devlinks	Don't follow device links when tracking probe
+			dependencies.
+
+  --exclude-parents	Don't follow parent devices when tracking probe
+			dependencies.
+
+EOF
+}
+
+function dev_to_detail() {
+	local i=0
+	while [ $i -lt ${#OUT_LIST[@]} ]
+	do
+		local C=${OUT_LIST[i]}
+		local S=${OUT_LIST[i+1]}
+		local D="'$(detail_chosen $C $S)'"
+		if [ ! -z "$D" ]
+		then
+			# This weirdness is needed to work with toybox when
+			# using the -t option.
+			printf '%05u\t%s\n' ${i} "$D" | tr -d \'
+		fi
+		i=$((i+2))
+	done
+}
+
+function already_seen() {
+	local i=0
+	while [ $i -lt ${#OUT_LIST[@]} ]
+	do
+		if [ "$1" = "${OUT_LIST[$i]}" ]
+		then
+			# if-statement treats 0 (no-error) as true
+			return 0
+		fi
+		i=$(($i+2))
+	done
+
+	# if-statement treats 1 (error) as false
+	return 1
+}
+
+# Return 0 (no-error/true) if parent was added
+function add_parent() {
+
+	if [ ${ALLOW_PARENTS} -eq 0 ]
+	then
+		return 1
+	fi
+
+	local CON=$1
+	# $CON could be a symlink path. So, we need to find the real path and
+	# then go up one level to find the real parent.
+	local PARENT=$(realpath $CON/..)
+
+	while [ ! -e ${PARENT}/driver ]
+	do
+		if [ "$PARENT" = "/sys/devices" ]
+		then
+			return 1
+		fi
+		PARENT=$(realpath $PARENT/..)
+	done
+
+	CONSUMERS+=($PARENT)
+	OUT_LIST+=(${CON} ${PARENT})
+	return 0
+}
+
+# Return 0 (no-error/true) if one or more suppliers were added
+function add_suppliers() {
+	local CON=$1
+	local RET=1
+
+	if [ ${ALLOW_DEVLINKS} -eq 0 ]
+	then
+		return 1
+	fi
+
+	SUPPLIER_LINKS=$(ls -1d $CON/supplier:* 2>/dev/null)
+	for SL in $SUPPLIER_LINKS;
+	do
+		SYNC_STATE=$(cat $SL/sync_state_only)
+
+		# sync_state_only links are proxy dependencies.
+		# They can also have cycles. So, don't follow them.
+		if [ "$SYNC_STATE" != '0' ]
+		then
+			continue
+		fi
+
+		SUPPLIER=$(realpath $SL/supplier)
+
+		if [ ! -e $SUPPLIER/driver -a ${ALLOW_NO_DRIVER} -eq 0 ]
+		then
+			continue
+		fi
+
+		CONSUMERS+=($SUPPLIER)
+		OUT_LIST+=(${CON} ${SUPPLIER})
+		RET=0
+	done
+
+	return $RET
+}
+
+function detail_compat() {
+	f=$1/of_node/compatible
+	if [ -e $f ]
+	then
+		echo -n $(cat $f)
+	else
+		echo -n $1
+	fi
+}
+
+function detail_module() {
+	f=$1/driver/module
+	if [ -e $f ]
+	then
+		echo -n $(basename $(realpath $f))
+	else
+		echo -n $1
+	fi
+}
+
+function detail_driver() {
+	f=$1/driver
+	if [ -e $f ]
+	then
+		echo -n $(basename $(realpath $f))
+	else
+		echo -n $1
+	fi
+}
+
+function detail_fwnode() {
+	f=$1/firmware_node
+	if [ ! -e $f ]
+	then
+		f=$1/of_node
+	fi
+
+	if [ -e $f ]
+	then
+		echo -n $(realpath $f)
+	else
+		echo -n $1
+	fi
+}
+
+function detail_graphviz() {
+	if [ "$2" != "ROOT" ]
+	then
+		echo -n "\"$(basename $2)\"->\"$(basename $1)\""
+	else
+		echo -n "\"$(basename $1)\""
+	fi
+}
+
+function detail_tsort() {
+	echo -n "\"$2\" \"$1\""
+}
+
+function detail_device() { echo -n $1; }
+
+alias detail=detail_device
+ALLOW_NO_DRIVER=0
+ALLOW_DEVLINKS=1
+ALLOW_PARENTS=1
+
+while [ $# -gt 0 ]
+do
+	ARG=$1
+	case $ARG in
+		--help)
+			help
+			exit 0
+			;;
+		-c)
+			alias detail=detail_compat
+			;;
+		-m)
+			alias detail=detail_module
+			;;
+		-d)
+			alias detail=detail_driver
+			;;
+		-f)
+			alias detail=detail_fwnode
+			;;
+		-g)
+			alias detail=detail_graphviz
+			;;
+		-t)
+			alias detail=detail_tsort
+			;;
+		--allow-no-driver)
+			ALLOW_NO_DRIVER=1
+			;;
+		--exclude-devlinks)
+			ALLOW_DEVLINKS=0
+			;;
+		--exclude-parents)
+			ALLOW_PARENTS=0
+			;;
+		*)
+			# Stop at the first argument that's not an option.
+			break
+			;;
+	esac
+	shift
+done
+
+function detail_chosen() {
+	detail $1 $2
+}
+
+if [ $# -eq 0 ]
+then
+	help
+	exit 1
+fi
+
+CONSUMERS=($@)
+OUT_LIST=()
+
+# Do a breadth first, non-recursive tracking of suppliers. The parent is also
+# considered a "supplier" as a device can't probe without its parent.
+i=0
+while [ $i -lt ${#CONSUMERS[@]} ]
+do
+	CONSUMER=$(realpath ${CONSUMERS[$i]})
+	i=$(($i+1))
+
+	if already_seen ${CONSUMER}
+	then
+		continue
+	fi
+
+	# If this is not a device with a driver, we don't care about its
+	# suppliers.
+	if [ ! -e ${CONSUMER}/driver -a ${ALLOW_NO_DRIVER} -eq 0 ]
+	then
+		continue
+	fi
+
+	ROOT=1
+
+	# Add suppliers to CONSUMERS list and output the consumer details.
+	#
+	# We don't need to worry about a cycle in the dependency chain causing
+	# infinite loops. That's because the kernel doesn't allow cycles in
+	# device links unless it's a sync_state_only device link. And we ignore
+	# sync_state_only device links inside add_suppliers.
+	if add_suppliers ${CONSUMER}
+	then
+		ROOT=0
+	fi
+
+	if add_parent ${CONSUMER}
+	then
+		ROOT=0
+	fi
+
+	if [ $ROOT -eq 1 ]
+	then
+		OUT_LIST+=(${CONSUMER} "ROOT")
+	fi
+done
+
+# Can NOT combine sort and uniq using sort -suk2 because stable sort in toybox
+# isn't really stable.
+dev_to_detail | sort -k2 -k1 | uniq -f 1 | sort | cut -f2-
+
+exit 0