Merge tag 'dt-for-robh' of git://git.secretlab.ca/git/linux into for-next

Pull DT changes from Grant Likely:

DT queued up for v3.16

Mostly bug fixes, but also some rework to improve path handling and device naming

13 files changed, 222 insertions, 84 deletions

diff --git a/arch/powerpc/include/asm/dcr-mmio.h b/arch/powerpc/include/asm/dcr-mmio.h
index acd491dbd45a..93a68b28e695 100644
--- a/arch/powerpc/include/asm/dcr-mmio.h
+++ b/arch/powerpc/include/asm/dcr-mmio.h
@@ -51,10 +51,6 @@ static inline void dcr_write_mmio(dcr_host_mmio_t host,
         out_be32(host.token + ((host.base + dcr_n) * host.stride), value);
 }
 
-extern u64 of_translate_dcr_address(struct device_node *dev,
-                                    unsigned int dcr_n,
-                                    unsigned int *stride);
-
 #endif /* __KERNEL__ */
 #endif /* _ASM_POWERPC_DCR_MMIO_H */
 
diff --git a/arch/powerpc/sysdev/dcr.c b/arch/powerpc/sysdev/dcr.c
index 1bd0eba4d355..e9056e438575 100644
--- a/arch/powerpc/sysdev/dcr.c
+++ b/arch/powerpc/sysdev/dcr.c
@@ -152,9 +152,9 @@ EXPORT_SYMBOL_GPL(dcr_resource_len);
 
 #ifdef CONFIG_PPC_DCR_MMIO
 
-u64 of_translate_dcr_address(struct device_node *dev,
-                             unsigned int dcr_n,
-                             unsigned int *out_stride)
+static u64 of_translate_dcr_address(struct device_node *dev,
+                                    unsigned int dcr_n,
+                                    unsigned int *out_stride)
 {
         struct device_node *dp;
         const u32 *p;
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index 5b47210889e0..9e9227e1762d 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -131,9 +131,12 @@ EXPORT_SYMBOL_GPL(platform_get_resource_byname);
  */
 int platform_get_irq_byname(struct platform_device *dev, const char *name)
 {
-        struct resource *r = platform_get_resource_byname(dev, IORESOURCE_IRQ,
-                                                          name);
+        struct resource *r;
+
+        if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node)
+                return of_irq_get_byname(dev->dev.of_node, name);
 
+        r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
         return r ? r->start : -ENXIO;
 }
 EXPORT_SYMBOL_GPL(platform_get_irq_byname);
diff --git a/drivers/of/base.c b/drivers/of/base.c
index 6d4ee22708c9..e67b308819c9 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -695,6 +695,22 @@ struct device_node *of_get_next_parent(struct device_node *node)
 }
 EXPORT_SYMBOL(of_get_next_parent);
 
+static struct device_node *__of_get_next_child(const struct device_node *node,
+                                                struct device_node *prev)
+{
+        struct device_node *next;
+
+        next = prev ? prev->sibling : node->child;
+        for (; next; next = next->sibling)
+                if (of_node_get(next))
+                        break;
+        of_node_put(prev);
+        return next;
+}
+#define __for_each_child_of_node(parent, child) \
+        for (child = __of_get_next_child(parent, NULL); child != NULL; \
+             child = __of_get_next_child(parent, child))
+
 /**
  *      of_get_next_child - Iterate a node childs
  *      @node:  parent node
@@ -710,11 +726,7 @@ struct device_node *of_get_next_child(const struct device_node *node,
         unsigned long flags;
 
         raw_spin_lock_irqsave(&devtree_lock, flags);
-        next = prev ? prev->sibling : node->child;
-        for (; next; next = next->sibling)
-                if (of_node_get(next))
-                        break;
-        of_node_put(prev);
+        next = __of_get_next_child(node, prev);
         raw_spin_unlock_irqrestore(&devtree_lock, flags);
         return next;
 }
@@ -771,23 +783,78 @@ struct device_node *of_get_child_by_name(const struct device_node *node,
 }
 EXPORT_SYMBOL(of_get_child_by_name);
 
+static struct device_node *__of_find_node_by_path(struct device_node *parent,
+                                                const char *path)
+{
+        struct device_node *child;
+        int len = strchrnul(path, '/') - path;
+
+        if (!len)
+                return NULL;
+
+        __for_each_child_of_node(parent, child) {
+                const char *name = strrchr(child->full_name, '/');
+                if (WARN(!name, "malformed device_node %s\n", child->full_name))
+                        continue;
+                name++;
+                if (strncmp(path, name, len) == 0 && (strlen(name) == len))
+                        return child;
+        }
+        return NULL;
+}
+
 /**
  *      of_find_node_by_path - Find a node matching a full OF path
- *      @path:  The full path to match
+ *      @path: Either the full path to match, or if the path does not
+ *             start with '/', the name of a property of the /aliases
+ *             node (an alias).  In the case of an alias, the node
+ *             matching the alias' value will be returned.
+ *
+ *      Valid paths:
+ *              /foo/bar        Full path
+ *              foo             Valid alias
+ *              foo/bar         Valid alias + relative path
  *
  *      Returns a node pointer with refcount incremented, use
  *      of_node_put() on it when done.
  */
 struct device_node *of_find_node_by_path(const char *path)
 {
-        struct device_node *np = of_allnodes;
+        struct device_node *np = NULL;
+        struct property *pp;
         unsigned long flags;
 
+        if (strcmp(path, "/") == 0)
+                return of_node_get(of_allnodes);
+
+        /* The path could begin with an alias */
+        if (*path != '/') {
+                char *p = strchrnul(path, '/');
+                int len = p - path;
+
+                /* of_aliases must not be NULL */
+                if (!of_aliases)
+                        return NULL;
+
+                for_each_property_of_node(of_aliases, pp) {
+                        if (strlen(pp->name) == len && !strncmp(pp->name, path, len)) {
+                                np = of_find_node_by_path(pp->value);
+                                break;
+                        }
+                }
+                if (!np)
+                        return NULL;
+                path = p;
+        }
+
+        /* Step down the tree matching path components */
         raw_spin_lock_irqsave(&devtree_lock, flags);
-        for (; np; np = np->allnext) {
-                if (np->full_name && (of_node_cmp(np->full_name, path) == 0)
-                    && of_node_get(np))
-                        break;
+        if (!np)
+                np = of_node_get(of_allnodes);
+        while (np && *path == '/') {
+                path++; /* Increment past '/' delimiter */
+                np = __of_find_node_by_path(np, path);
+                path = strchrnul(path, '/');
         }
         raw_spin_unlock_irqrestore(&devtree_lock, flags);
         return np;
@@ -1800,7 +1867,7 @@ int of_update_property(struct device_node *np, struct property *newprop)
 {
         struct property **next, *oldprop;
         unsigned long flags;
-        int rc, found = 0;
+        int rc;
 
         rc = of_property_notify(OF_RECONFIG_UPDATE_PROPERTY, np, newprop);
         if (rc)
@@ -1809,30 +1876,34 @@ int of_update_property(struct device_node *np, struct property *newprop)
         if (!newprop->name)
                 return -EINVAL;
 
-        oldprop = of_find_property(np, newprop->name, NULL);
-        if (!oldprop)
-                return of_add_property(np, newprop);
-
         raw_spin_lock_irqsave(&devtree_lock, flags);
         next = &np->properties;
-        while (*next) {
+        oldprop = __of_find_property(np, newprop->name, NULL);
+        if (!oldprop) {
+                /* add the new node */
+                rc = __of_add_property(np, newprop);
+        } else while (*next) {
+                /* replace the node */
                 if (*next == oldprop) {
-                        /* found the node */
                         newprop->next = oldprop->next;
                         *next = newprop;
                         oldprop->next = np->deadprops;
                         np->deadprops = oldprop;
-                        found = 1;
                         break;
                 }
                 next = &(*next)->next;
         }
         raw_spin_unlock_irqrestore(&devtree_lock, flags);
-        if (!found)
-                return -ENODEV;
+        if (rc)
+                return rc;
+
+        /* At early boot, bail out and defer setup to of_init() */
+        if (!of_kset)
+                return 0;
 
         /* Update the sysfs attribute */
-        sysfs_remove_bin_file(&np->kobj, &oldprop->attr);
+        if (oldprop)
+                sysfs_remove_bin_file(&np->kobj, &oldprop->attr);
         __of_add_property_sysfs(np, newprop);
 
         return 0;
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index a6f83ea107ae..17be90f5445f 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -324,7 +324,7 @@ static void __unflatten_device_tree(void *blob,
 
         /* First pass, scan for size */
         start = 0;
-        size = (unsigned long)unflatten_dt_node(blob, 0, &start, NULL, NULL, 0);
+        size = (unsigned long)unflatten_dt_node(blob, NULL, &start, NULL, NULL, 0);
         size = ALIGN(size, 4);
 
         pr_debug("  size is %lx, allocating...\n", size);
@@ -748,7 +748,7 @@ int __init early_init_dt_scan_memory(unsigned long node, const char *uname,
                  * The longtrail doesn't have a device_type on the
                  * /memory node, so look for the node called /memory@0.
                  */
-                if (depth != 1 || strcmp(uname, "memory@0") != 0)
+                if (!IS_ENABLED(CONFIG_PPC32) || depth != 1 || strcmp(uname, "memory@0") != 0)
                         return 0;
         } else if (strcmp(type, "memory") != 0)
                 return 0;
diff --git a/drivers/of/irq.c b/drivers/of/irq.c
index 5aeb89411350..3e06a699352d 100644
--- a/drivers/of/irq.c
+++ b/drivers/of/irq.c
@@ -406,6 +406,28 @@ int of_irq_get(struct device_node *dev, int index)
 }
 
 /**
+ * of_irq_get_byname - Decode a node's IRQ and return it as a Linux irq number
+ * @dev: pointer to device tree node
+ * @name: irq name
+ *
+ * Returns Linux irq number on success, or -EPROBE_DEFER if the irq domain
+ * is not yet created, or error code in case of any other failure.
+ */
+int of_irq_get_byname(struct device_node *dev, const char *name)
+{
+        int index;
+
+        if (unlikely(!name))
+                return -EINVAL;
+
+        index = of_property_match_string(dev, "interrupt-names", name);
+        if (index < 0)
+                return index;
+
+        return of_irq_get(dev, index);
+}
+
+/**
  * of_irq_count - Count the number of IRQs a node uses
  * @dev: pointer to device tree node
  */
diff --git a/drivers/of/of_pci_irq.c b/drivers/of/of_pci_irq.c
index 8736bc7676c5..1710d9dc7fc2 100644
--- a/drivers/of/of_pci_irq.c
+++ b/drivers/of/of_pci_irq.c
@@ -18,8 +18,6 @@ int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq
 {
         struct device_node *dn, *ppnode;
         struct pci_dev *ppdev;
-        u32 lspec;
-        __be32 lspec_be;
         __be32 laddr[3];
         u8 pin;
         int rc;
@@ -46,7 +44,6 @@ int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq
                 return -ENODEV;
 
         /* Now we walk up the PCI tree */
-        lspec = pin;
         for (;;) {
                 /* Get the pci_dev of our parent */
                 ppdev = pdev->bus->self;
@@ -80,14 +77,13 @@ int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq
                 /* We can only get here if we hit a P2P bridge with no node,
                  * let's do standard swizzling and try again
                  */
-                lspec = pci_swizzle_interrupt_pin(pdev, lspec);
+                pin = pci_swizzle_interrupt_pin(pdev, pin);
                 pdev = ppdev;
         }
 
         out_irq->np = ppnode;
         out_irq->args_count = 1;
-        out_irq->args[0] = lspec;
-        lspec_be = cpu_to_be32(lspec);
+        out_irq->args[0] = pin;
         laddr[0] = cpu_to_be32((pdev->bus->number << 16) | (pdev->devfn << 8));
         laddr[1] = laddr[2] = cpu_to_be32(0);
         return of_irq_parse_raw(laddr, out_irq);
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index d0009b3614af..52780a72d09d 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -51,10 +51,6 @@ struct platform_device *of_find_device_by_node(struct device_node *np)
 }
 EXPORT_SYMBOL(of_find_device_by_node);
 
-#if defined(CONFIG_PPC_DCR)
-#include <asm/dcr.h>
-#endif
-
 #ifdef CONFIG_OF_ADDRESS
 /*
  * The following routines scan a subtree and registers a device for
@@ -68,57 +64,35 @@ EXPORT_SYMBOL(of_find_device_by_node);
  * of_device_make_bus_id - Use the device node data to assign a unique name
  * @dev: pointer to device structure that is linked to a device tree node
  *
- * This routine will first try using either the dcr-reg or the reg property
- * value to derive a unique name.  As a last resort it will use the node
- * name followed by a unique number.
+ * This routine will first try using the translated bus address to
+ * derive a unique name. If it cannot, then it will prepend names from
+ * parent nodes until a unique name can be derived.
  */
 void of_device_make_bus_id(struct device *dev)
 {
-        static atomic_t bus_no_reg_magic;
         struct device_node *node = dev->of_node;
         const __be32 *reg;
         u64 addr;
-        int magic;
 
-#ifdef CONFIG_PPC_DCR
-        /*
-         * If it's a DCR based device, use 'd' for native DCRs
-         * and 'D' for MMIO DCRs.
-         */
-        reg = of_get_property(node, "dcr-reg", NULL);
-        if (reg) {
-#ifdef CONFIG_PPC_DCR_NATIVE
-                dev_set_name(dev, "d%x.%s", *reg, node->name);
-#else /* CONFIG_PPC_DCR_NATIVE */
-                u64 addr = of_translate_dcr_address(node, *reg, NULL);
-                if (addr != OF_BAD_ADDR) {
-                        dev_set_name(dev, "D%llx.%s",
-                                     (unsigned long long)addr, node->name);
+        /* Construct the name, using parent nodes if necessary to ensure uniqueness */
+        while (node->parent) {
+                /*
+                 * If the address can be translated, then that is as much
+                 * uniqueness as we need. Make it the first component and return
+                 */
+                reg = of_get_property(node, "reg", NULL);
+                if (reg && (addr = of_translate_address(node, reg)) != OF_BAD_ADDR) {
+                        dev_set_name(dev, dev_name(dev) ? "%llx.%s:%s" : "%llx.%s",
+                                     (unsigned long long)addr, node->name,
+                                     dev_name(dev));
                         return;
                 }
-#endif /* !CONFIG_PPC_DCR_NATIVE */
-        }
-#endif /* CONFIG_PPC_DCR */
 
-        /*
-         * For MMIO, get the physical address
-         */
-        reg = of_get_property(node, "reg", NULL);
-        if (reg) {
-                addr = of_translate_address(node, reg);
-                if (addr != OF_BAD_ADDR) {
-                        dev_set_name(dev, "%llx.%s",
-                                     (unsigned long long)addr, node->name);
-                        return;
-                }
+                /* format arguments only used if dev_name() resolves to NULL */
+                dev_set_name(dev, dev_name(dev) ? "%s:%s" : "%s",
+                             strrchr(node->full_name, '/') + 1, dev_name(dev));
+                node = node->parent;
         }
-
-        /*
-         * No BusID, use the node name and add a globally incremented
-         * counter (and pray...)
-         */
-        magic = atomic_add_return(1, &bus_no_reg_magic);
-        dev_set_name(dev, "%s.%d", node->name, magic - 1);
 }
 
 /**
diff --git a/drivers/of/selftest.c b/drivers/of/selftest.c
index 2588faaaa305..077314eebb95 100644
--- a/drivers/of/selftest.c
+++ b/drivers/of/selftest.c
@@ -31,6 +31,51 @@ static struct selftest_results {
         } \
 }
 
+static void __init of_selftest_find_node_by_name(void)
+{
+        struct device_node *np;
+
+        np = of_find_node_by_path("/testcase-data");
+        selftest(np && !strcmp("/testcase-data", np->full_name),
+                "find /testcase-data failed\n");
+        of_node_put(np);
+
+        /* Test if trailing '/' works */
+        np = of_find_node_by_path("/testcase-data/");
+        selftest(!np, "trailing '/' on /testcase-data/ should fail\n");
+
+        np = of_find_node_by_path("/testcase-data/phandle-tests/consumer-a");
+        selftest(np && !strcmp("/testcase-data/phandle-tests/consumer-a", np->full_name),
+                "find /testcase-data/phandle-tests/consumer-a failed\n");
+        of_node_put(np);
+
+        np = of_find_node_by_path("testcase-alias");
+        selftest(np && !strcmp("/testcase-data", np->full_name),
+                "find testcase-alias failed\n");
+        of_node_put(np);
+
+        /* Test if trailing '/' works on aliases */
+        np = of_find_node_by_path("testcase-alias/");
+        selftest(!np, "trailing '/' on testcase-alias/ should fail\n");
+
+        np = of_find_node_by_path("testcase-alias/phandle-tests/consumer-a");
+        selftest(np && !strcmp("/testcase-data/phandle-tests/consumer-a", np->full_name),
+                "find testcase-alias/phandle-tests/consumer-a failed\n");
+        of_node_put(np);
+
+        np = of_find_node_by_path("/testcase-data/missing-path");
+        selftest(!np, "non-existent path returned node %s\n", np->full_name);
+        of_node_put(np);
+
+        np = of_find_node_by_path("missing-alias");
+        selftest(!np, "non-existent alias returned node %s\n", np->full_name);
+        of_node_put(np);
+
+        np = of_find_node_by_path("testcase-alias/missing-path");
+        selftest(!np, "non-existent alias with relative path returned node %s\n", np->full_name);
+        of_node_put(np);
+}
+
 static void __init of_selftest_dynamic(void)
 {
         struct device_node *np;
@@ -484,6 +529,7 @@ static int __init of_selftest(void)
         of_node_put(np);
 
         pr_info("start of selftest - you will see error messages\n");
+        of_selftest_find_node_by_name();
         of_selftest_dynamic();
         of_selftest_parse_phandle_with_args();
         of_selftest_property_match_string();
diff --git a/drivers/of/testcase-data/tests-phandle.dtsi b/drivers/of/testcase-data/tests-phandle.dtsi
index 788a4c24b8f5..ce0fe083d406 100644
--- a/drivers/of/testcase-data/tests-phandle.dtsi
+++ b/drivers/of/testcase-data/tests-phandle.dtsi
@@ -1,6 +1,10 @@
 
 / {
-        testcase-data {
+        aliases {
+                testcase-alias = &testcase;
+        };
+
+        testcase: testcase-data {
                 security-password = "password";
                 duplicate-name = "duplicate";
                 duplicate-name { };
diff --git a/include/linux/of_irq.h b/include/linux/of_irq.h
index 6404253d810d..bfec136a6d1e 100644
--- a/include/linux/of_irq.h
+++ b/include/linux/of_irq.h
@@ -45,6 +45,7 @@ extern void of_irq_init(const struct of_device_id *matches);
 #ifdef CONFIG_OF_IRQ
 extern int of_irq_count(struct device_node *dev);
 extern int of_irq_get(struct device_node *dev, int index);
+extern int of_irq_get_byname(struct device_node *dev, const char *name);
 #else
 static inline int of_irq_count(struct device_node *dev)
 {
@@ -54,6 +55,10 @@ static inline int of_irq_get(struct device_node *dev, int index)
 {
         return 0;
 }
+static inline int of_irq_get_byname(struct device_node *dev, const char *name)
+{
+        return 0;
+}
 #endif
 
 #if defined(CONFIG_OF)
diff --git a/include/linux/string.h b/include/linux/string.h
index ac889c5ea11b..d36977e029af 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -52,6 +52,9 @@ extern int strncasecmp(const char *s1, const char *s2, size_t n);
 #ifndef __HAVE_ARCH_STRCHR
 extern char * strchr(const char *,int);
 #endif
+#ifndef __HAVE_ARCH_STRCHRNUL
+extern char * strchrnul(const char *,int);
+#endif
 #ifndef __HAVE_ARCH_STRNCHR
 extern char * strnchr(const char *, size_t, int);
 #endif
diff --git a/lib/string.c b/lib/string.c
index 9b1f9062a202..e0c20eb362f0 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -301,6 +301,24 @@ char *strchr(const char *s, int c)
 EXPORT_SYMBOL(strchr);
 #endif
 
+#ifndef __HAVE_ARCH_STRCHRNUL
+/**
+ * strchrnul - Find and return a character in a string, or end of string
+ * @s: The string to be searched
+ * @c: The character to search for
+ *
+ * Returns pointer to first occurrence of 'c' in s. If c is not found, then
+ * return a pointer to the null byte at the end of s.
+ */
+char *strchrnul(const char *s, int c)
+{
+        while (*s && *s != (char)c)
+                s++;
+        return (char *)s;
+}
+EXPORT_SYMBOL(strchrnul);
+#endif
+
 #ifndef __HAVE_ARCH_STRRCHR
 /**
  * strrchr - Find the last occurrence of a character in a string