pinctrl: move subsystem mutex to pinctrl_dev struct
[pandora-kernel.git] / drivers / pinctrl / core.c
index 59f5a96..c3d222e 100644 (file)
@@ -14,6 +14,7 @@
 #define pr_fmt(fmt) "pinctrl core: " fmt
 
 #include <linux/kernel.h>
+#include <linux/kref.h>
 #include <linux/export.h>
 #include <linux/init.h>
 #include <linux/device.h>
 #include <linux/pinctrl/consumer.h>
 #include <linux/pinctrl/pinctrl.h>
 #include <linux/pinctrl/machine.h>
+
+#ifdef CONFIG_GPIOLIB
+#include <asm-generic/gpio.h>
+#endif
+
 #include "core.h"
 #include "devicetree.h"
 #include "pinmux.h"
 #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;
-};
 
 static bool pinctrl_dummy_state;
 
-/* Mutex taken by all entry points */
-DEFINE_MUTEX(pinctrl_mutex);
+/* Mutex taken to protect pinctrl_list */
+DEFINE_MUTEX(pinctrl_list_mutex);
+
+/* Mutex taken to protect pinctrl_maps */
+DEFINE_MUTEX(pinctrl_maps_mutex);
+
+/* Mutex taken to protect pinctrldev_list */
+DEFINE_MUTEX(pinctrldev_list_mutex);
 
 /* Global list of pin control devices (struct pinctrl_dev) */
-LIST_HEAD(pinctrldev_list);
+static LIST_HEAD(pinctrldev_list);
 
 /* List of pin controller handles (struct pinctrl) */
 static LIST_HEAD(pinctrl_list);
 
 /* List of pinctrl maps (struct pinctrl_maps) */
-static LIST_HEAD(pinctrl_maps);
+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_])
 
 /**
  * pinctrl_provide_dummies() - indicate if pinctrl provides dummy state support
@@ -83,6 +79,12 @@ const char *pinctrl_dev_get_name(struct pinctrl_dev *pctldev)
 }
 EXPORT_SYMBOL_GPL(pinctrl_dev_get_name);
 
+const char *pinctrl_dev_get_devname(struct pinctrl_dev *pctldev)
+{
+       return dev_name(pctldev->dev);
+}
+EXPORT_SYMBOL_GPL(pinctrl_dev_get_devname);
+
 void *pinctrl_dev_get_drvdata(struct pinctrl_dev *pctldev)
 {
        return pctldev->driver_data;
@@ -115,6 +117,23 @@ struct pinctrl_dev *get_pinctrl_dev_from_devname(const char *devname)
        return found ? pctldev : NULL;
 }
 
+struct pinctrl_dev *get_pinctrl_dev_from_of_node(struct device_node *np)
+{
+       struct pinctrl_dev *pctldev;
+
+       mutex_lock(&pinctrldev_list_mutex);
+
+       list_for_each_entry(pctldev, &pinctrldev_list, node)
+               if (pctldev->dev->of_node == np) {
+                       mutex_unlock(&pinctrldev_list_mutex);
+                       return pctldev;
+               }
+
+       mutex_lock(&pinctrldev_list_mutex);
+
+       return NULL;
+}
+
 /**
  * pin_get_from_name() - look up a pin number from a name
  * @pctldev: the pin control device to lookup the pin on
@@ -174,9 +193,9 @@ bool pin_is_valid(struct pinctrl_dev *pctldev, int pin)
        if (pin < 0)
                return false;
 
-       mutex_lock(&pinctrl_mutex);
+       mutex_lock(&pctldev->mutex);
        pindesc = pin_desc_get(pctldev, pin);
-       mutex_unlock(&pinctrl_mutex);
+       mutex_unlock(&pctldev->mutex);
 
        return pindesc != NULL;
 }
@@ -273,18 +292,57 @@ pinctrl_match_gpio_range(struct pinctrl_dev *pctldev, unsigned gpio)
 {
        struct pinctrl_gpio_range *range = NULL;
 
+       mutex_lock(&pctldev->mutex);
        /* Loop over the ranges */
        list_for_each_entry(range, &pctldev->gpio_ranges, node) {
                /* Check if we're in the valid range */
                if (gpio >= range->base &&
                    gpio < range->base + range->npins) {
+                       mutex_unlock(&pctldev->mutex);
                        return range;
                }
        }
-
+       mutex_unlock(&pctldev->mutex);
        return NULL;
 }
 
+/**
+ * pinctrl_ready_for_gpio_range() - check if other GPIO pins of
+ * the same GPIO chip are in range
+ * @gpio: gpio pin to check taken from the global GPIO pin space
+ *
+ * This function is complement of pinctrl_match_gpio_range(). If the return
+ * value of pinctrl_match_gpio_range() is NULL, this function could be used
+ * to check whether pinctrl device is ready or not. Maybe some GPIO pins
+ * of the same GPIO chip don't have back-end pinctrl interface.
+ * If the return value is true, it means that pinctrl device is ready & the
+ * certain GPIO pin doesn't have back-end pinctrl device. If the return value
+ * is false, it means that pinctrl device may not be ready.
+ */
+#ifdef CONFIG_GPIOLIB
+static bool pinctrl_ready_for_gpio_range(unsigned gpio)
+{
+       struct pinctrl_dev *pctldev;
+       struct pinctrl_gpio_range *range = NULL;
+       struct gpio_chip *chip = gpio_to_chip(gpio);
+
+       /* Loop over the pin controllers */
+       list_for_each_entry(pctldev, &pinctrldev_list, node) {
+               /* Loop over the ranges */
+               list_for_each_entry(range, &pctldev->gpio_ranges, node) {
+                       /* Check if any gpio range overlapped with gpio chip */
+                       if (range->base + range->npins - 1 < chip->base ||
+                           range->base > chip->base + chip->ngpio - 1)
+                               continue;
+                       return true;
+               }
+       }
+       return false;
+}
+#else
+static bool pinctrl_ready_for_gpio_range(unsigned gpio) { return true; }
+#endif
+
 /**
  * pinctrl_get_device_gpio_range() - find device for GPIO range
  * @gpio: the pin to locate the pin controller for
@@ -328,9 +386,9 @@ static int pinctrl_get_device_gpio_range(unsigned gpio,
 void pinctrl_add_gpio_range(struct pinctrl_dev *pctldev,
                            struct pinctrl_gpio_range *range)
 {
-       mutex_lock(&pinctrl_mutex);
+       mutex_lock(&pctldev->mutex);
        list_add_tail(&range->node, &pctldev->gpio_ranges);
-       mutex_unlock(&pinctrl_mutex);
+       mutex_unlock(&pctldev->mutex);
 }
 EXPORT_SYMBOL_GPL(pinctrl_add_gpio_range);
 
@@ -348,17 +406,25 @@ EXPORT_SYMBOL_GPL(pinctrl_add_gpio_ranges);
 struct pinctrl_dev *pinctrl_find_and_add_gpio_range(const char *devname,
                struct pinctrl_gpio_range *range)
 {
-       struct pinctrl_dev *pctldev = get_pinctrl_dev_from_devname(devname);
+       struct pinctrl_dev *pctldev;
+
+       mutex_lock(&pinctrldev_list_mutex);
+
+       pctldev = get_pinctrl_dev_from_devname(devname);
 
        /*
         * If we can't find this device, let's assume that is because
         * it has not probed yet, so the driver trying to register this
         * range need to defer probing.
         */
-       if (!pctldev)
+       if (!pctldev) {
+               mutex_unlock(&pinctrldev_list_mutex);
                return ERR_PTR(-EPROBE_DEFER);
-
+       }
        pinctrl_add_gpio_range(pctldev, range);
+
+       mutex_unlock(&pinctrldev_list_mutex);
+
        return pctldev;
 }
 EXPORT_SYMBOL_GPL(pinctrl_find_and_add_gpio_range);
@@ -374,14 +440,17 @@ pinctrl_find_gpio_range_from_pin(struct pinctrl_dev *pctldev,
 {
        struct pinctrl_gpio_range *range = NULL;
 
+       mutex_lock(&pctldev->mutex);
        /* Loop over the ranges */
        list_for_each_entry(range, &pctldev->gpio_ranges, node) {
                /* Check if we're in the valid range */
                if (pin >= range->pin_base &&
                    pin < range->pin_base + range->npins) {
+                       mutex_unlock(&pctldev->mutex);
                        return range;
                }
        }
+       mutex_unlock(&pctldev->mutex);
 
        return NULL;
 }
@@ -395,9 +464,9 @@ EXPORT_SYMBOL_GPL(pinctrl_find_gpio_range_from_pin);
 void pinctrl_remove_gpio_range(struct pinctrl_dev *pctldev,
                               struct pinctrl_gpio_range *range)
 {
-       mutex_lock(&pinctrl_mutex);
+       mutex_lock(&pctldev->mutex);
        list_del(&range->node);
-       mutex_unlock(&pinctrl_mutex);
+       mutex_unlock(&pctldev->mutex);
 }
 EXPORT_SYMBOL_GPL(pinctrl_remove_gpio_range);
 
@@ -448,11 +517,13 @@ int pinctrl_request_gpio(unsigned gpio)
        int ret;
        int pin;
 
-       mutex_lock(&pinctrl_mutex);
+       mutex_lock(&pinctrldev_list_mutex);
 
        ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range);
        if (ret) {
-               mutex_unlock(&pinctrl_mutex);
+               if (pinctrl_ready_for_gpio_range(gpio))
+                       ret = 0;
+               mutex_unlock(&pinctrldev_list_mutex);
                return ret;
        }
 
@@ -461,7 +532,7 @@ int pinctrl_request_gpio(unsigned gpio)
 
        ret = pinmux_request_gpio(pctldev, range, pin, gpio);
 
-       mutex_unlock(&pinctrl_mutex);
+       mutex_unlock(&pinctrldev_list_mutex);
        return ret;
 }
 EXPORT_SYMBOL_GPL(pinctrl_request_gpio);
@@ -481,20 +552,22 @@ void pinctrl_free_gpio(unsigned gpio)
        int ret;
        int pin;
 
-       mutex_lock(&pinctrl_mutex);
+       mutex_lock(&pinctrldev_list_mutex);
 
        ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range);
        if (ret) {
-               mutex_unlock(&pinctrl_mutex);
+               mutex_unlock(&pinctrldev_list_mutex);
                return;
        }
+       mutex_lock(&pctldev->mutex);
 
        /* Convert to the pin controllers number space */
        pin = gpio - range->base + range->pin_base;
 
        pinmux_free_gpio(pctldev, pin, range);
 
-       mutex_unlock(&pinctrl_mutex);
+       mutex_unlock(&pctldev->mutex);
+       mutex_unlock(&pinctrldev_list_mutex);
 }
 EXPORT_SYMBOL_GPL(pinctrl_free_gpio);
 
@@ -505,14 +578,24 @@ static int pinctrl_gpio_direction(unsigned gpio, bool input)
        int ret;
        int pin;
 
+       mutex_lock(&pinctrldev_list_mutex);
+
        ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range);
-       if (ret)
+       if (ret) {
+               mutex_unlock(&pinctrldev_list_mutex);
                return ret;
+       }
+
+       mutex_lock(&pctldev->mutex);
 
        /* Convert to the pin controllers number space */
        pin = gpio - range->base + range->pin_base;
+       ret = pinmux_gpio_direction(pctldev, range, pin, input);
+
+       mutex_unlock(&pctldev->mutex);
+       mutex_unlock(&pinctrldev_list_mutex);
 
-       return pinmux_gpio_direction(pctldev, range, pin, input);
+       return ret;
 }
 
 /**
@@ -525,11 +608,7 @@ static int pinctrl_gpio_direction(unsigned gpio, bool input)
  */
 int pinctrl_gpio_direction_input(unsigned gpio)
 {
-       int ret;
-       mutex_lock(&pinctrl_mutex);
-       ret = pinctrl_gpio_direction(gpio, true);
-       mutex_unlock(&pinctrl_mutex);
-       return ret;
+       return pinctrl_gpio_direction(gpio, true);
 }
 EXPORT_SYMBOL_GPL(pinctrl_gpio_direction_input);
 
@@ -543,11 +622,7 @@ EXPORT_SYMBOL_GPL(pinctrl_gpio_direction_input);
  */
 int pinctrl_gpio_direction_output(unsigned gpio)
 {
-       int ret;
-       mutex_lock(&pinctrl_mutex);
-       ret = pinctrl_gpio_direction(gpio, false);
-       mutex_unlock(&pinctrl_mutex);
-       return ret;
+       return pinctrl_gpio_direction(gpio, false);
 }
 EXPORT_SYMBOL_GPL(pinctrl_gpio_direction_output);
 
@@ -609,13 +684,16 @@ static int add_setting(struct pinctrl *p, struct pinctrl_map const *map)
 
        setting->pctldev = get_pinctrl_dev_from_devname(map->ctrl_dev_name);
        if (setting->pctldev == NULL) {
-               dev_info(p->dev, "unknown pinctrl device %s in map entry, deferring probe",
-                       map->ctrl_dev_name);
                kfree(setting);
+               /* Do not defer probing of hogs (circular loop) */
+               if (!strcmp(map->ctrl_dev_name, map->dev_name))
+                       return -ENODEV;
                /*
                 * OK let us guess that the driver is not there yet, and
                 * let's defer obtaining this pinctrl handle to later...
                 */
+               dev_info(p->dev, "unknown pinctrl device %s in map entry, deferring probe",
+                       map->ctrl_dev_name);
                return -EPROBE_DEFER;
        }
 
@@ -647,14 +725,18 @@ static struct pinctrl *find_pinctrl(struct device *dev)
 {
        struct pinctrl *p;
 
+       mutex_lock(&pinctrl_list_mutex);
        list_for_each_entry(p, &pinctrl_list, node)
-               if (p->dev == dev)
+               if (p->dev == dev) {
+                       mutex_unlock(&pinctrl_list_mutex);
                        return p;
+               }
 
+       mutex_unlock(&pinctrl_list_mutex);
        return NULL;
 }
 
-static void pinctrl_put_locked(struct pinctrl *p, bool inlist);
+static void pinctrl_free(struct pinctrl *p, bool inlist);
 
 static struct pinctrl *create_pinctrl(struct device *dev)
 {
@@ -687,6 +769,7 @@ static struct pinctrl *create_pinctrl(struct device *dev)
 
        devname = dev_name(dev);
 
+       mutex_lock(&pinctrl_maps_mutex);
        /* Iterate over the pin control maps to locate the right ones */
        for_each_maps(maps_node, i, map) {
                /* Map must be for this device */
@@ -694,11 +777,34 @@ static struct pinctrl *create_pinctrl(struct device *dev)
                        continue;
 
                ret = add_setting(p, map);
-               if (ret < 0) {
-                       pinctrl_put_locked(p, false);
+               /*
+                * At this point the adding of a setting may:
+                *
+                * - Defer, if the pinctrl device is not yet available
+                * - Fail, if the pinctrl device is not yet available,
+                *   AND the setting is a hog. We cannot defer that, since
+                *   the hog will kick in immediately after the device
+                *   is registered.
+                *
+                * If the error returned was not -EPROBE_DEFER then we
+                * accumulate the errors to see if we end up with
+                * an -EPROBE_DEFER later, as that is the worst case.
+                */
+               if (ret == -EPROBE_DEFER) {
+                       pinctrl_free(p, false);
+                       mutex_unlock(&pinctrl_maps_mutex);
                        return ERR_PTR(ret);
                }
        }
+       mutex_unlock(&pinctrl_maps_mutex);
+
+       if (ret < 0) {
+               /* If some other error than deferral occured, return here */
+               pinctrl_free(p, false);
+               return ERR_PTR(ret);
+       }
+
+       kref_init(&p->users);
 
        /* Add the pinctrl handle to the global list */
        list_add_tail(&p->node, &pinctrl_list);
@@ -706,56 +812,60 @@ static struct pinctrl *create_pinctrl(struct device *dev)
        return p;
 }
 
-static struct pinctrl *pinctrl_get_locked(struct device *dev)
+/**
+ * pinctrl_get() - retrieves the pinctrl handle for a device
+ * @dev: the device to obtain the handle for
+ */
+struct pinctrl *pinctrl_get(struct device *dev)
 {
        struct pinctrl *p;
 
        if (WARN_ON(!dev))
                return ERR_PTR(-EINVAL);
 
+       /*
+        * See if somebody else (such as the device core) has already
+        * obtained a handle to the pinctrl for this device. In that case,
+        * return another pointer to it.
+        */
        p = find_pinctrl(dev);
-       if (p != NULL)
-               return ERR_PTR(-EBUSY);
+       if (p != NULL) {
+               dev_dbg(dev, "obtain a copy of previously claimed pinctrl\n");
+               kref_get(&p->users);
+               return p;
+       }
 
        return create_pinctrl(dev);
 }
+EXPORT_SYMBOL_GPL(pinctrl_get);
 
-/**
- * pinctrl_get() - retrieves the pinctrl handle for a device
- * @dev: the device to obtain the handle for
- */
-struct pinctrl *pinctrl_get(struct device *dev)
+static void pinctrl_free_setting(bool disable_setting,
+                                struct pinctrl_setting *setting)
 {
-       struct pinctrl *p;
-
-       mutex_lock(&pinctrl_mutex);
-       p = pinctrl_get_locked(dev);
-       mutex_unlock(&pinctrl_mutex);
-
-       return p;
+       switch (setting->type) {
+       case PIN_MAP_TYPE_MUX_GROUP:
+               if (disable_setting)
+                       pinmux_disable_setting(setting);
+               pinmux_free_setting(setting);
+               break;
+       case PIN_MAP_TYPE_CONFIGS_PIN:
+       case PIN_MAP_TYPE_CONFIGS_GROUP:
+               pinconf_free_setting(setting);
+               break;
+       default:
+               break;
+       }
 }
-EXPORT_SYMBOL_GPL(pinctrl_get);
 
-static void pinctrl_put_locked(struct pinctrl *p, bool inlist)
+static void pinctrl_free(struct pinctrl *p, bool inlist)
 {
        struct pinctrl_state *state, *n1;
        struct pinctrl_setting *setting, *n2;
 
+       mutex_lock(&pinctrl_list_mutex);
        list_for_each_entry_safe(state, n1, &p->states, node) {
                list_for_each_entry_safe(setting, n2, &state->settings, node) {
-                       switch (setting->type) {
-                       case PIN_MAP_TYPE_MUX_GROUP:
-                               if (state == p->state)
-                                       pinmux_disable_setting(setting);
-                               pinmux_free_setting(setting);
-                               break;
-                       case PIN_MAP_TYPE_CONFIGS_PIN:
-                       case PIN_MAP_TYPE_CONFIGS_GROUP:
-                               pinconf_free_setting(setting);
-                               break;
-                       default:
-                               break;
-                       }
+                       pinctrl_free_setting(state == p->state, setting);
                        list_del(&setting->node);
                        kfree(setting);
                }
@@ -768,22 +878,37 @@ static void pinctrl_put_locked(struct pinctrl *p, bool inlist)
        if (inlist)
                list_del(&p->node);
        kfree(p);
+       mutex_unlock(&pinctrl_list_mutex);
+}
+
+/**
+ * pinctrl_release() - release the pinctrl handle
+ * @kref: the kref in the pinctrl being released
+ */
+static void pinctrl_release(struct kref *kref)
+{
+       struct pinctrl *p = container_of(kref, struct pinctrl, users);
+
+       pinctrl_free(p, true);
 }
 
 /**
- * pinctrl_put() - release a previously claimed pinctrl handle
+ * pinctrl_put() - decrease use count on a previously claimed pinctrl handle
  * @p: the pinctrl handle to release
  */
 void pinctrl_put(struct pinctrl *p)
 {
-       mutex_lock(&pinctrl_mutex);
-       pinctrl_put_locked(p, true);
-       mutex_unlock(&pinctrl_mutex);
+       kref_put(&p->users, pinctrl_release);
 }
 EXPORT_SYMBOL_GPL(pinctrl_put);
 
-static struct pinctrl_state *pinctrl_lookup_state_locked(struct pinctrl *p,
-                                                        const char *name)
+/**
+ * pinctrl_lookup_state() - retrieves a state handle from a pinctrl handle
+ * @p: the pinctrl handle to retrieve the state from
+ * @name: the state name to retrieve
+ */
+struct pinctrl_state *pinctrl_lookup_state(struct pinctrl *p,
+                                                const char *name)
 {
        struct pinctrl_state *state;
 
@@ -800,28 +925,17 @@ static struct pinctrl_state *pinctrl_lookup_state_locked(struct pinctrl *p,
 
        return state;
 }
+EXPORT_SYMBOL_GPL(pinctrl_lookup_state);
 
 /**
- * pinctrl_lookup_state() - retrieves a state handle from a pinctrl handle
- * @p: the pinctrl handle to retrieve the state from
- * @name: the state name to retrieve
+ * pinctrl_select_state() - select/activate/program a pinctrl state to HW
+ * @p: the pinctrl handle for the device that requests configuration
+ * @state: the state handle to select/activate/program
  */
-struct pinctrl_state *pinctrl_lookup_state(struct pinctrl *p, const char *name)
-{
-       struct pinctrl_state *s;
-
-       mutex_lock(&pinctrl_mutex);
-       s = pinctrl_lookup_state_locked(p, name);
-       mutex_unlock(&pinctrl_mutex);
-
-       return s;
-}
-EXPORT_SYMBOL_GPL(pinctrl_lookup_state);
-
-static int pinctrl_select_state_locked(struct pinctrl *p,
-                                      struct pinctrl_state *state)
+int pinctrl_select_state(struct pinctrl *p, struct pinctrl_state *state)
 {
        struct pinctrl_setting *setting, *setting2;
+       struct pinctrl_state *old_state = p->state;
        int ret;
 
        if (p->state == state)
@@ -855,7 +969,7 @@ static int pinctrl_select_state_locked(struct pinctrl *p,
                }
        }
 
-       p->state = state;
+       p->state = NULL;
 
        /* Apply all the settings for the new state */
        list_for_each_entry(setting, &state->settings, node) {
@@ -871,27 +985,36 @@ static int pinctrl_select_state_locked(struct pinctrl *p,
                        ret = -EINVAL;
                        break;
                }
+
                if (ret < 0) {
-                       /* FIXME: Difficult to return to prev state */
-                       return ret;
+                       goto unapply_new_state;
                }
        }
 
+       p->state = state;
+
        return 0;
-}
 
-/**
- * pinctrl_select() - select/activate/program a pinctrl state to HW
- * @p: the pinctrl handle for the device that requests configuratio
- * @state: the state handle to select/activate/program
- */
-int pinctrl_select_state(struct pinctrl *p, struct pinctrl_state *state)
-{
-       int ret;
+unapply_new_state:
+       dev_err(p->dev, "Error applying setting, reverse things back\n");
+
+       list_for_each_entry(setting2, &state->settings, node) {
+               if (&setting2->node == &setting->node)
+                       break;
+               /*
+                * All we can do here is pinmux_disable_setting.
+                * That means that some pins are muxed differently now
+                * than they were before applying the setting (We can't
+                * "unmux a pin"!), but it's not a big deal since the pins
+                * are free to be muxed by another apply_setting.
+                */
+               if (setting2->type == PIN_MAP_TYPE_MUX_GROUP)
+                       pinmux_disable_setting(setting2);
+       }
 
-       mutex_lock(&pinctrl_mutex);
-       ret = pinctrl_select_state_locked(p, state);
-       mutex_unlock(&pinctrl_mutex);
+       /* There's no infinite recursive loop here because p->state is NULL */
+       if (old_state)
+               pinctrl_select_state(p, old_state);
 
        return ret;
 }
@@ -946,9 +1069,8 @@ static int devm_pinctrl_match(struct device *dev, void *res, void *data)
  */
 void devm_pinctrl_put(struct pinctrl *p)
 {
-       WARN_ON(devres_destroy(p->dev, devm_pinctrl_release,
+       WARN_ON(devres_release(p->dev, devm_pinctrl_release,
                               devm_pinctrl_match, p));
-       pinctrl_put(p);
 }
 EXPORT_SYMBOL_GPL(devm_pinctrl_put);
 
@@ -1022,10 +1144,10 @@ int pinctrl_register_map(struct pinctrl_map const *maps, unsigned num_maps,
        }
 
        if (!locked)
-               mutex_lock(&pinctrl_mutex);
+               mutex_lock(&pinctrl_maps_mutex);
        list_add_tail(&maps_node->node, &pinctrl_maps);
        if (!locked)
-               mutex_unlock(&pinctrl_mutex);
+               mutex_unlock(&pinctrl_maps_mutex);
 
        return 0;
 }
@@ -1047,14 +1169,41 @@ void pinctrl_unregister_map(struct pinctrl_map const *map)
 {
        struct pinctrl_maps *maps_node;
 
+       mutex_lock(&pinctrl_maps_mutex);
        list_for_each_entry(maps_node, &pinctrl_maps, node) {
                if (maps_node->maps == map) {
                        list_del(&maps_node->node);
+                       mutex_unlock(&pinctrl_maps_mutex);
                        return;
                }
        }
+       mutex_unlock(&pinctrl_maps_mutex);
 }
 
+/**
+ * pinctrl_force_sleep() - turn a given controller device into sleep state
+ * @pctldev: pin controller device
+ */
+int pinctrl_force_sleep(struct pinctrl_dev *pctldev)
+{
+       if (!IS_ERR(pctldev->p) && !IS_ERR(pctldev->hog_sleep))
+               return pinctrl_select_state(pctldev->p, pctldev->hog_sleep);
+       return 0;
+}
+EXPORT_SYMBOL_GPL(pinctrl_force_sleep);
+
+/**
+ * pinctrl_force_default() - turn a given controller device into default state
+ * @pctldev: pin controller device
+ */
+int pinctrl_force_default(struct pinctrl_dev *pctldev)
+{
+       if (!IS_ERR(pctldev->p) && !IS_ERR(pctldev->hog_default))
+               return pinctrl_select_state(pctldev->p, pctldev->hog_default);
+       return 0;
+}
+EXPORT_SYMBOL_GPL(pinctrl_force_default);
+
 #ifdef CONFIG_DEBUG_FS
 
 static int pinctrl_pins_show(struct seq_file *s, void *what)
@@ -1065,7 +1214,7 @@ static int pinctrl_pins_show(struct seq_file *s, void *what)
 
        seq_printf(s, "registered pins: %d\n", pctldev->desc->npins);
 
-       mutex_lock(&pinctrl_mutex);
+       mutex_lock(&pctldev->mutex);
 
        /* The pin number can be retrived from the pin controller descriptor */
        for (i = 0; i < pctldev->desc->npins; i++) {
@@ -1087,7 +1236,7 @@ static int pinctrl_pins_show(struct seq_file *s, void *what)
                seq_puts(s, "\n");
        }
 
-       mutex_unlock(&pinctrl_mutex);
+       mutex_unlock(&pctldev->mutex);
 
        return 0;
 }
@@ -1098,8 +1247,9 @@ static int pinctrl_groups_show(struct seq_file *s, void *what)
        const struct pinctrl_ops *ops = pctldev->desc->pctlops;
        unsigned ngroups, selector = 0;
 
+       mutex_lock(&pctldev->mutex);
+
        ngroups = ops->get_groups_count(pctldev);
-       mutex_lock(&pinctrl_mutex);
 
        seq_puts(s, "registered pin groups:\n");
        while (selector < ngroups) {
@@ -1120,7 +1270,7 @@ static int pinctrl_groups_show(struct seq_file *s, void *what)
                        for (i = 0; i < num_pins; i++) {
                                pname = pin_get_name(pctldev, pins[i]);
                                if (WARN_ON(!pname)) {
-                                       mutex_unlock(&pinctrl_mutex);
+                                       mutex_unlock(&pctldev->mutex);
                                        return -EINVAL;
                                }
                                seq_printf(s, "pin %d (%s)\n", pins[i], pname);
@@ -1130,7 +1280,7 @@ static int pinctrl_groups_show(struct seq_file *s, void *what)
                selector++;
        }
 
-       mutex_unlock(&pinctrl_mutex);
+       mutex_unlock(&pctldev->mutex);
 
        return 0;
 }
@@ -1142,7 +1292,7 @@ static int pinctrl_gpioranges_show(struct seq_file *s, void *what)
 
        seq_puts(s, "GPIO ranges handled:\n");
 
-       mutex_lock(&pinctrl_mutex);
+       mutex_lock(&pctldev->mutex);
 
        /* Loop over the ranges */
        list_for_each_entry(range, &pctldev->gpio_ranges, node) {
@@ -1153,7 +1303,7 @@ static int pinctrl_gpioranges_show(struct seq_file *s, void *what)
                           (range->pin_base + range->npins - 1));
        }
 
-       mutex_unlock(&pinctrl_mutex);
+       mutex_unlock(&pctldev->mutex);
 
        return 0;
 }
@@ -1164,7 +1314,7 @@ static int pinctrl_devices_show(struct seq_file *s, void *what)
 
        seq_puts(s, "name [pinmux] [pinconf]\n");
 
-       mutex_lock(&pinctrl_mutex);
+       mutex_lock(&pinctrldev_list_mutex);
 
        list_for_each_entry(pctldev, &pinctrldev_list, node) {
                seq_printf(s, "%s ", pctldev->desc->name);
@@ -1179,7 +1329,7 @@ static int pinctrl_devices_show(struct seq_file *s, void *what)
                seq_puts(s, "\n");
        }
 
-       mutex_unlock(&pinctrl_mutex);
+       mutex_unlock(&pinctrldev_list_mutex);
 
        return 0;
 }
@@ -1208,8 +1358,7 @@ static int pinctrl_maps_show(struct seq_file *s, void *what)
 
        seq_puts(s, "Pinctrl maps:\n");
 
-       mutex_lock(&pinctrl_mutex);
-
+       mutex_lock(&pinctrl_maps_mutex);
        for_each_maps(maps_node, i, map) {
                seq_printf(s, "device %s\nstate %s\ntype %s (%d)\n",
                           map->dev_name, map->name, map_type(map->type),
@@ -1233,8 +1382,7 @@ static int pinctrl_maps_show(struct seq_file *s, void *what)
 
                seq_printf(s, "\n");
        }
-
-       mutex_unlock(&pinctrl_mutex);
+       mutex_unlock(&pinctrl_maps_mutex);
 
        return 0;
 }
@@ -1247,7 +1395,7 @@ static int pinctrl_show(struct seq_file *s, void *what)
 
        seq_puts(s, "Requested pin control handlers their pinmux maps:\n");
 
-       mutex_lock(&pinctrl_mutex);
+       mutex_lock(&pinctrl_list_mutex);
 
        list_for_each_entry(p, &pinctrl_list, node) {
                seq_printf(s, "device: %s current state: %s\n",
@@ -1279,7 +1427,7 @@ static int pinctrl_show(struct seq_file *s, void *what)
                }
        }
 
-       mutex_unlock(&pinctrl_mutex);
+       mutex_unlock(&pinctrl_list_mutex);
 
        return 0;
 }
@@ -1465,6 +1613,7 @@ struct pinctrl_dev *pinctrl_register(struct pinctrl_desc *pctldesc,
        INIT_RADIX_TREE(&pctldev->pin_desc_tree, GFP_KERNEL);
        INIT_LIST_HEAD(&pctldev->gpio_ranges);
        pctldev->dev = dev;
+       mutex_init(&pctldev->mutex);
 
        /* check core ops for sanity */
        if (pinctrl_check_ops(pctldev)) {
@@ -1494,31 +1643,37 @@ struct pinctrl_dev *pinctrl_register(struct pinctrl_desc *pctldesc,
                goto out_err;
        }
 
-       mutex_lock(&pinctrl_mutex);
-
+       mutex_lock(&pinctrldev_list_mutex);
        list_add_tail(&pctldev->node, &pinctrldev_list);
+       mutex_unlock(&pinctrldev_list_mutex);
+
+       pctldev->p = pinctrl_get(pctldev->dev);
 
-       pctldev->p = pinctrl_get_locked(pctldev->dev);
        if (!IS_ERR(pctldev->p)) {
-               struct pinctrl_state *s =
-                       pinctrl_lookup_state_locked(pctldev->p,
-                                                   PINCTRL_STATE_DEFAULT);
-               if (IS_ERR(s)) {
+               pctldev->hog_default =
+                       pinctrl_lookup_state(pctldev->p, PINCTRL_STATE_DEFAULT);
+               if (IS_ERR(pctldev->hog_default)) {
                        dev_dbg(dev, "failed to lookup the default state\n");
                } else {
-                       if (pinctrl_select_state_locked(pctldev->p, s))
+                       if (pinctrl_select_state(pctldev->p,
+                                               pctldev->hog_default))
                                dev_err(dev,
                                        "failed to select default state\n");
                }
-       }
 
-       mutex_unlock(&pinctrl_mutex);
+               pctldev->hog_sleep =
+                       pinctrl_lookup_state(pctldev->p,
+                                                   PINCTRL_STATE_SLEEP);
+               if (IS_ERR(pctldev->hog_sleep))
+                       dev_dbg(dev, "failed to lookup the sleep state\n");
+       }
 
        pinctrl_init_device_debugfs(pctldev);
 
        return pctldev;
 
 out_err:
+       mutex_destroy(&pctldev->mutex);
        kfree(pctldev);
        return NULL;
 }
@@ -1536,12 +1691,13 @@ void pinctrl_unregister(struct pinctrl_dev *pctldev)
        if (pctldev == NULL)
                return;
 
-       pinctrl_remove_device_debugfs(pctldev);
+       mutex_lock(&pinctrldev_list_mutex);
+       mutex_lock(&pctldev->mutex);
 
-       mutex_lock(&pinctrl_mutex);
+       pinctrl_remove_device_debugfs(pctldev);
 
        if (!IS_ERR(pctldev->p))
-               pinctrl_put_locked(pctldev->p, true);
+               pinctrl_put(pctldev->p);
 
        /* TODO: check that no pinmuxes are still active? */
        list_del(&pctldev->node);
@@ -1552,9 +1708,10 @@ void pinctrl_unregister(struct pinctrl_dev *pctldev)
        list_for_each_entry_safe(range, n, &pctldev->gpio_ranges, node)
                list_del(&range->node);
 
+       mutex_unlock(&pctldev->mutex);
+       mutex_destroy(&pctldev->mutex);
        kfree(pctldev);
-
-       mutex_unlock(&pinctrl_mutex);
+       mutex_unlock(&pinctrldev_list_mutex);
 }
 EXPORT_SYMBOL_GPL(pinctrl_unregister);