1 files changed, 75 insertions, 45 deletions

diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
index feadf1c31133..50bcc511193e 100644
--- a/drivers/pinctrl/core.c
+++ b/drivers/pinctrl/core.c
@@ -7,6 +7,8 @@
  *
  * Author: Linus Walleij <linus.walleij@linaro.org>
  *
+ * Copyright (C) 2012 NVIDIA CORPORATION. All rights reserved.
+ *
  * License terms: GNU General Public License (GPL) version 2
  */
 #define pr_fmt(fmt) "pinctrl core: " fmt
@@ -31,6 +33,18 @@
 #include "pinconf.h"
 
 /**
+ * struct pinctrl_maps - a list item containing part of the mapping table
+ * @node: mapping table list node
+ * @maps: array of mapping table entries
+ * @num_maps: the number of entries in @maps
+ */
+struct pinctrl_maps {
+        struct list_head node;
+        struct pinctrl_map const *maps;
+        unsigned num_maps;
+};
+
+/**
  * struct pinctrl_hog - a list item to stash control hogs
  * @node: pin control hog list node
  * @map: map entry responsible for this hogging
@@ -51,8 +65,14 @@ static DEFINE_MUTEX(pinctrl_list_mutex);
 static LIST_HEAD(pinctrl_list);
 
 /* Global pinctrl maps */
-static struct pinctrl_map *pinctrl_maps;
-static unsigned pinctrl_maps_num;
+static DEFINE_MUTEX(pinctrl_maps_mutex);
+static LIST_HEAD(pinctrl_maps);
+
+#define for_each_maps(_maps_node_, _i_, _map_) \
+        list_for_each_entry(_maps_node_, &pinctrl_maps, node) \
+                for (_i_ = 0, _map_ = &_maps_node_->maps[_i_]; \
+                        _i_ < _maps_node_->num_maps; \
+                        i++, _map_ = &_maps_node_->maps[_i_])
 
 const char *pinctrl_dev_get_name(struct pinctrl_dev *pctldev)
 {
@@ -454,23 +474,17 @@ int pinctrl_gpio_direction_output(unsigned gpio)
 }
 EXPORT_SYMBOL_GPL(pinctrl_gpio_direction_output);
 
-/**
- * pinctrl_get() - retrieves the pin controller handle for a certain device
- * @dev: the device to get the pin controller handle for
- * @name: an optional specific control mapping name or NULL, the name is only
- *      needed if you want to have more than one mapping per device, or if you
- *      need an anonymous pin control (not tied to any specific device)
- */
-struct pinctrl *pinctrl_get(struct device *dev, const char *name)
+static struct pinctrl *pinctrl_get_locked(struct device *dev, const char *name)
 {
-        struct pinctrl_map const *map = NULL;
         struct pinctrl_dev *pctldev = NULL;
         const char *devname = NULL;
         struct pinctrl *p;
         bool found_map;
         unsigned num_maps = 0;
         int ret = -ENODEV;
+        struct pinctrl_maps *maps_node;
         int i;
+        struct pinctrl_map const *map;
 
         /* We must have dev or ID or both */
         if (!dev && !name)
@@ -494,8 +508,7 @@ struct pinctrl *pinctrl_get(struct device *dev, const char *name)
         pinmux_init_pinctrl_handle(p);
 
         /* Iterate over the pin control maps to locate the right ones */
-        for (i = 0; i < pinctrl_maps_num; i++) {
-                map = &pinctrl_maps[i];
+        for_each_maps(maps_node, i, map) {
                 found_map = false;
 
                 /*
@@ -515,7 +528,6 @@ struct pinctrl *pinctrl_get(struct device *dev, const char *name)
                 pr_debug("in map, found pctldev %s to handle function %s",
                          dev_name(pctldev->dev), map->function);
 
-
                 /*
                  * If we're looking for a specific named map, this must match,
                  * else we loop and look for the next.
@@ -574,6 +586,24 @@ struct pinctrl *pinctrl_get(struct device *dev, const char *name)
 
         return p;
 }
+
+/**
+ * pinctrl_get() - retrieves the pin controller handle for a certain device
+ * @dev: the device to get the pin controller handle for
+ * @name: an optional specific control mapping name or NULL, the name is only
+ *      needed if you want to have more than one mapping per device, or if you
+ *      need an anonymous pin control (not tied to any specific device)
+ */
+struct pinctrl *pinctrl_get(struct device *dev, const char *name)
+{
+        struct pinctrl *p;
+
+        mutex_lock(&pinctrl_maps_mutex);
+        p = pinctrl_get_locked(dev, name);
+        mutex_unlock(&pinctrl_maps_mutex);
+
+        return p;
+}
 EXPORT_SYMBOL_GPL(pinctrl_get);
 
 /**
@@ -649,8 +679,8 @@ EXPORT_SYMBOL_GPL(pinctrl_disable);
 int pinctrl_register_mappings(struct pinctrl_map const *maps,
                               unsigned num_maps)
 {
-        void *tmp_maps;
         int i;
+        struct pinctrl_maps *maps_node;
 
         pr_debug("add %d pinmux maps\n", num_maps);
 
@@ -684,31 +714,23 @@ int pinctrl_register_mappings(struct pinctrl_map const *maps,
                                  maps[i].function);
         }
 
-        /*
-         * Make a copy of the map array - string pointers will end up in the
-         * kernel const section anyway so these do not need to be deep copied.
-         */
-        if (!pinctrl_maps_num) {
-                /* On first call, just copy them */
-                tmp_maps = kmemdup(maps,
-                                   sizeof(struct pinctrl_map) * num_maps,
-                                   GFP_KERNEL);
-                if (!tmp_maps)
-                        return -ENOMEM;
-        } else {
-                /* Subsequent calls, reallocate array to new size */
-                size_t oldsize = sizeof(struct pinctrl_map) * pinctrl_maps_num;
-                size_t newsize = sizeof(struct pinctrl_map) * num_maps;
+        maps_node = kzalloc(sizeof(*maps_node), GFP_KERNEL);
+        if (!maps_node) {
+                pr_err("failed to alloc struct pinctrl_maps\n");
+                return -ENOMEM;
+        }
 
-                tmp_maps = krealloc(pinctrl_maps,
-                                    oldsize + newsize, GFP_KERNEL);
-                if (!tmp_maps)
-                        return -ENOMEM;
-                memcpy((tmp_maps + oldsize), maps, newsize);
+        maps_node->num_maps = num_maps;
+        maps_node->maps = kmemdup(maps, sizeof(*maps) * num_maps, GFP_KERNEL);
+        if (!maps_node->maps) {
+                kfree(maps_node);
+                return -ENOMEM;
         }
 
-        pinctrl_maps = tmp_maps;
-        pinctrl_maps_num += num_maps;
+        mutex_lock(&pinctrl_maps_mutex);
+        list_add_tail(&maps_node->node, &pinctrl_maps);
+        mutex_unlock(&pinctrl_maps_mutex);
+
         return 0;
 }
 
@@ -724,7 +746,7 @@ static int pinctrl_hog_map(struct pinctrl_dev *pctldev,
         if (!hog)
                 return -ENOMEM;
 
-        p = pinctrl_get(pctldev->dev, map->name);
+        p = pinctrl_get_locked(pctldev->dev, map->name);
         if (IS_ERR(p)) {
                 kfree(hog);
                 dev_err(pctldev->dev,
@@ -768,23 +790,28 @@ int pinctrl_hog_maps(struct pinctrl_dev *pctldev)
         struct device *dev = pctldev->dev;
         const char *devname = dev_name(dev);
         int ret;
+        struct pinctrl_maps *maps_node;
         int i;
+        struct pinctrl_map const *map;
 
         INIT_LIST_HEAD(&pctldev->pinctrl_hogs);
         mutex_init(&pctldev->pinctrl_hogs_lock);
 
-        for (i = 0; i < pinctrl_maps_num; i++) {
-                struct pinctrl_map const *map = &pinctrl_maps[i];
-
+        mutex_lock(&pinctrl_maps_mutex);
+        for_each_maps(maps_node, i, map) {
                 if (map->ctrl_dev_name &&
                     !strcmp(map->ctrl_dev_name, devname) &&
                     !strcmp(map->dev_name, devname)) {
                         /* OK time to hog! */
                         ret = pinctrl_hog_map(pctldev, map);
-                        if (ret)
+                        if (ret) {
+                                mutex_unlock(&pinctrl_maps_mutex);
                                 return ret;
+                        }
                 }
         }
+        mutex_unlock(&pinctrl_maps_mutex);
+
         return 0;
 }
 
@@ -900,13 +927,14 @@ static int pinctrl_gpioranges_show(struct seq_file *s, void *what)
 
 static int pinctrl_maps_show(struct seq_file *s, void *what)
 {
+        struct pinctrl_maps *maps_node;
         int i;
+        struct pinctrl_map const *map;
 
         seq_puts(s, "Pinctrl maps:\n");
 
-        for (i = 0; i < pinctrl_maps_num; i++) {
-                struct pinctrl_map const *map = &pinctrl_maps[i];
-
+        mutex_lock(&pinctrl_maps_mutex);
+        for_each_maps(maps_node, i, map) {
                 seq_printf(s, "%s:\n", map->name);
                 if (map->dev_name)
                         seq_printf(s, "  device: %s\n",
@@ -919,6 +947,8 @@ static int pinctrl_maps_show(struct seq_file *s, void *what)
                 seq_printf(s, "  group: %s\n", map->group ? map->group :
                            "(default)");
         }
+        mutex_unlock(&pinctrl_maps_mutex);
+
         return 0;
 }