Merge tag 'gpio-v5.5-updates-for-linus-part-2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux into devel

gpio: updates for v5.5

- add MODULE_ALIAS() for bd70528 (makes it possible to autoload the
  module from user-space)
- use proper irc_chip names in gpio-em and gpio-rcar
- expose the line bias settings to user-space in the form of new request
  flags
- expose a new ioctl() to user-space which allows to change certain
  proprties of requested lines without releasing them first
- various updates for gpio-tegra186: debounce support, code
  simplification and interrupt routing
- use platform_get_irq() in gpio-em for some code shrinkage
- remove leftovers after recent gpio-mmio changes

Author: linusw

Documentation/admin-guide/kernel-parameters.rst

@@ -127,6 +127,7 @@ parameter is applicable::
 	NET	Appropriate network support is enabled.
 	NUMA	NUMA support is enabled.
 	NFS	Appropriate NFS support is enabled.
+	OF	Devicetree is enabled.
 	OSS	OSS sound support is enabled.
 	PV_OPS	A paravirtualized kernel is enabled.
 	PARIDE	The ParIDE (parallel port IDE) subsystem is enabled.

Documentation/admin-guide/kernel-parameters.txt

@@ -3194,6 +3194,12 @@
 			This can be set from sysctl after boot.
 			See Documentation/admin-guide/sysctl/vm.rst for details.
 
+	of_devlink	[OF, KNL] Create device links between consumer and
+			supplier devices by scanning the devictree to infer the
+			consumer/supplier relationships.  A consumer device
+			will not be probed until all the supplier devices have
+			probed successfully.
+
 	ohci1394_dma=early	[HW] enable debugging via the ohci1394 driver.
 			See Documentation/debugging-via-ohci1394.txt for more
 			info.

Documentation/driver-api/device_link.rst

@@ -281,7 +281,8 @@ State machine
   :c:func:`driver_bound()`.)
 
 * Before a consumer device is probed, presence of supplier drivers is
-  verified by checking that links to suppliers are in ``DL_STATE_AVAILABLE``
+  verified by checking the consumer device is not in the wait_for_suppliers
+  list and by checking that links to suppliers are in ``DL_STATE_AVAILABLE``
   state.  The state of the links is updated to ``DL_STATE_CONSUMER_PROBE``.
   (Call to :c:func:`device_links_check_suppliers()` from
   :c:func:`really_probe()`.)

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

@@ -316,6 +316,10 @@ IOMAP
   devm_ioremap_nocache()
   devm_ioremap_wc()
   devm_ioremap_resource() : checks resource, requests memory region, ioremaps
+  devm_ioremap_resource_wc()
+  devm_platform_ioremap_resource() : calls devm_ioremap_resource() for platform device
+  devm_platform_ioremap_resource_wc()
+  devm_platform_ioremap_resource_byname()
   devm_iounmap()
   pcim_iomap()
   pcim_iomap_regions()	: do request_region() and iomap() on multiple BARs

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

@@ -169,6 +169,49 @@ A driver's probe() may return a negative errno value to indicate that
 the driver did not bind to this device, in which case it should have
 released all resources it allocated::
 
+	void (*sync_state)(struct device *dev);
+
+sync_state is called only once for a device. It's called when all the consumer
+devices of the device have successfully probed. The list of consumers of the
+device is obtained by looking at the device links connecting that device to its
+consumer devices.
+
+The first attempt to call sync_state() is made during late_initcall_sync() to
+give firmware and drivers time to link devices to each other. During the first
+attempt at calling sync_state(), if all the consumers of the device at that
+point in time have already probed successfully, sync_state() is called right
+away. If there are no consumers of the device during the first attempt, that
+too is considered as "all consumers of the device have probed" and sync_state()
+is called right away.
+
+If during the first attempt at calling sync_state() for a device, there are
+still consumers that haven't probed successfully, the sync_state() call is
+postponed and reattempted in the future only when one or more consumers of the
+device probe successfully. If during the reattempt, the driver core finds that
+there are one or more consumers of the device that haven't probed yet, then
+sync_state() call is postponed again.
+
+A typical use case for sync_state() is to have the kernel cleanly take over
+management of devices from the bootloader. For example, if a device is left on
+and at a particular hardware configuration by the bootloader, the device's
+driver might need to keep the device in the boot configuration until all the
+consumers of the device have probed. Once all the consumers of the device have
+probed, the device's driver can synchronize the hardware state of the device to
+match the aggregated software state requested by all the consumers. Hence the
+name sync_state().
+
+While obvious examples of resources that can benefit from sync_state() include
+resources such as regulator, sync_state() can also be useful for complex
+resources like IOMMUs. For example, IOMMUs with multiple consumers (devices
+whose addresses are remapped by the IOMMU) might need to keep their mappings
+fixed at (or additive to) the boot configuration until all its consumers have
+probed.
+
+While the typical use case for sync_state() is to have the kernel cleanly take
+over management of devices from the bootloader, the usage of sync_state() is
+not restricted to that. Use it whenever it makes sense to take an action after
+all the consumers of a device have probed.
+
 	int 	(*remove)	(struct device *dev);
 
 remove is called to unbind a driver from a device. This may be

Documentation/filesystems/debugfs.txt

@@ -68,41 +68,49 @@ actually necessary; the debugfs code provides a number of helper functions
 for simple situations.  Files containing a single integer value can be
 created with any of:
 
-    struct dentry *debugfs_create_u8(const char *name, umode_t mode,
-				     struct dentry *parent, u8 *value);
-    struct dentry *debugfs_create_u16(const char *name, umode_t mode,
-				      struct dentry *parent, u16 *value);
+    void debugfs_create_u8(const char *name, umode_t mode,
+			   struct dentry *parent, u8 *value);
+    void debugfs_create_u16(const char *name, umode_t mode,
+			    struct dentry *parent, u16 *value);
     struct dentry *debugfs_create_u32(const char *name, umode_t mode,
 				      struct dentry *parent, u32 *value);
-    struct dentry *debugfs_create_u64(const char *name, umode_t mode,
-				      struct dentry *parent, u64 *value);
+    void debugfs_create_u64(const char *name, umode_t mode,
+			    struct dentry *parent, u64 *value);
 
 These files support both reading and writing the given value; if a specific
 file should not be written to, simply set the mode bits accordingly.  The
 values in these files are in decimal; if hexadecimal is more appropriate,
 the following functions can be used instead:
 
-    struct dentry *debugfs_create_x8(const char *name, umode_t mode,
-				     struct dentry *parent, u8 *value);
-    struct dentry *debugfs_create_x16(const char *name, umode_t mode,
-				      struct dentry *parent, u16 *value);
-    struct dentry *debugfs_create_x32(const char *name, umode_t mode,
-				      struct dentry *parent, u32 *value);
-    struct dentry *debugfs_create_x64(const char *name, umode_t mode,
-				      struct dentry *parent, u64 *value);
+    void debugfs_create_x8(const char *name, umode_t mode,
+			   struct dentry *parent, u8 *value);
+    void debugfs_create_x16(const char *name, umode_t mode,
+			    struct dentry *parent, u16 *value);
+    void debugfs_create_x32(const char *name, umode_t mode,
+			    struct dentry *parent, u32 *value);
+    void debugfs_create_x64(const char *name, umode_t mode,
+			    struct dentry *parent, u64 *value);
 
 These functions are useful as long as the developer knows the size of the
 value to be exported.  Some types can have different widths on different
-architectures, though, complicating the situation somewhat.  There is a
-function meant to help out in one special case:
+architectures, though, complicating the situation somewhat.  There are
+functions meant to help out in such special cases:
 
-    struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
-				         struct dentry *parent, 
-					 size_t *value);
+    void debugfs_create_size_t(const char *name, umode_t mode,
+			       struct dentry *parent, size_t *value);
 
 As might be expected, this function will create a debugfs file to represent
 a variable of type size_t.
 
+Similarly, there are helpers for variables of type unsigned long, in decimal
+and hexadecimal:
+
+    struct dentry *debugfs_create_ulong(const char *name, umode_t mode,
+					struct dentry *parent,
+					unsigned long *value);
+    void debugfs_create_xul(const char *name, umode_t mode,
+			    struct dentry *parent, unsigned long *value);
+
 Boolean values can be placed in debugfs with:
 
     struct dentry *debugfs_create_bool(const char *name, umode_t mode,
@@ -114,8 +122,8 @@ lower-case values, or 1 or 0.  Any other input will be silently ignored.
 
 Also, atomic_t values can be placed in debugfs with:
 
-    struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
-				struct dentry *parent, atomic_t *value)
+    void debugfs_create_atomic_t(const char *name, umode_t mode,
+				 struct dentry *parent, atomic_t *value)
 
 A read of this file will get atomic_t values, and a write of this file
 will set atomic_t values.

arch/powerpc/platforms/pseries/dtl.c

@@ -19,7 +19,6 @@
 
 struct dtl {
 	struct dtl_entry	*buf;
-	struct dentry		*file;
 	int			cpu;
 	int			buf_entries;
 	u64			last_idx;
@@ -320,63 +319,38 @@ static const struct file_operations dtl_fops = {
 
 static struct dentry *dtl_dir;
 
-static int dtl_setup_file(struct dtl *dtl)
+static void dtl_setup_file(struct dtl *dtl)
 {
 	char name[10];
 
 	sprintf(name, "cpu-%d", dtl->cpu);
 
-	dtl->file = debugfs_create_file(name, 0400, dtl_dir, dtl, &dtl_fops);
-	if (!dtl->file)
-		return -ENOMEM;
-
-	return 0;
+	debugfs_create_file(name, 0400, dtl_dir, dtl, &dtl_fops);
 }
 
 static int dtl_init(void)
 {
-	struct dentry *event_mask_file, *buf_entries_file;
-	int rc, i;
+	int i;
 
 	if (!firmware_has_feature(FW_FEATURE_SPLPAR))
 		return -ENODEV;
 
 	/* set up common debugfs structure */
 
-	rc = -ENOMEM;
 	dtl_dir = debugfs_create_dir("dtl", powerpc_debugfs_root);
-	if (!dtl_dir) {
-		printk(KERN_WARNING "%s: can't create dtl root dir\n",
-				__func__);
-		goto err;
-	}
 
-	event_mask_file = debugfs_create_x8("dtl_event_mask", 0600,
-				dtl_dir, &dtl_event_mask);
-	buf_entries_file = debugfs_create_u32("dtl_buf_entries", 0400,
-				dtl_dir, &dtl_buf_entries);
-
-	if (!event_mask_file || !buf_entries_file) {
-		printk(KERN_WARNING "%s: can't create dtl files\n", __func__);
-		goto err_remove_dir;
-	}
+	debugfs_create_x8("dtl_event_mask", 0600, dtl_dir, &dtl_event_mask);
+	debugfs_create_u32("dtl_buf_entries", 0400, dtl_dir, &dtl_buf_entries);
 
 	/* set up the per-cpu log structures */
 	for_each_possible_cpu(i) {
 		struct dtl *dtl = &per_cpu(cpu_dtl, i);
 		spin_lock_init(&dtl->lock);
 		dtl->cpu = i;
 
-		rc = dtl_setup_file(dtl);
-		if (rc)
-			goto err_remove_dir;
+		dtl_setup_file(dtl);
 	}
 
 	return 0;
-
-err_remove_dir:
-	debugfs_remove_recursive(dtl_dir);
-err:
-	return rc;
 }
 machine_arch_initcall(pseries, dtl_init);

arch/powerpc/platforms/pseries/hvCall_inst.c

@@ -129,7 +129,6 @@ static void probe_hcall_exit(void *ignored, unsigned long opcode, long retval,
 static int __init hcall_inst_init(void)
 {
 	struct dentry *hcall_root;
-	struct dentry *hcall_file;
 	char cpu_name_buf[CPU_NAME_BUF_SIZE];
 	int cpu;
 
@@ -145,17 +144,12 @@ static int __init hcall_inst_init(void)
 	}
 
 	hcall_root = debugfs_create_dir(HCALL_ROOT_DIR, NULL);
-	if (!hcall_root)
-		return -ENOMEM;
 
 	for_each_possible_cpu(cpu) {
 		snprintf(cpu_name_buf, CPU_NAME_BUF_SIZE, "cpu%d", cpu);
-		hcall_file = debugfs_create_file(cpu_name_buf, 0444,
-						 hcall_root,
-						 per_cpu(hcall_stats, cpu),
-						 &hcall_inst_seq_fops);
-		if (!hcall_file)
-			return -ENOMEM;
+		debugfs_create_file(cpu_name_buf, 0444, hcall_root,
+				    per_cpu(hcall_stats, cpu),
+				    &hcall_inst_seq_fops);
 	}
 
 	return 0;

arch/powerpc/platforms/pseries/lpar.c

@@ -1998,24 +1998,11 @@ static int __init vpa_debugfs_init(void)
 		return 0;
 
 	vpa_dir = debugfs_create_dir("vpa", powerpc_debugfs_root);
-	if (!vpa_dir) {
-		pr_warn("%s: can't create vpa root dir\n", __func__);
-		return -ENOMEM;
-	}
 
 	/* set up the per-cpu vpa file*/
 	for_each_possible_cpu(i) {
-		struct dentry *d;
-
 		sprintf(name, "cpu-%ld", i);
-
-		d = debugfs_create_file(name, 0400, vpa_dir, (void *)i,
-					&vpa_fops);
-		if (!d) {
-			pr_warn("%s: can't create per-cpu vpa file\n",
-					__func__);
-			return -ENOMEM;
-		}
+		debugfs_create_file(name, 0400, vpa_dir, (void *)i, &vpa_fops);
 	}
 
 	return 0;

arch/sh/drivers/Makefile

@@ -3,7 +3,7 @@
 # Makefile for the Linux SuperH-specific device drivers.
 #
 
-obj-y		+= dma/
+obj-y		+= dma/ platform_early.o
 
 obj-$(CONFIG_PCI)		+= pci/
 obj-$(CONFIG_SUPERHYWAY)	+= superhyway/