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path: root/drivers/reset/core.c
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Diffstat (limited to 'drivers/reset/core.c')
-rw-r--r--drivers/reset/core.c386
1 files changed, 169 insertions, 217 deletions
diff --git a/drivers/reset/core.c b/drivers/reset/core.c
index dba74e857be6..0135dd0ae204 100644
--- a/drivers/reset/core.c
+++ b/drivers/reset/core.c
@@ -4,20 +4,22 @@
*
* Copyright 2013 Philipp Zabel, Pengutronix
*/
+
+#include <linux/acpi.h>
#include <linux/atomic.h>
+#include <linux/auxiliary_bus.h>
#include <linux/cleanup.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/export.h>
-#include <linux/kernel.h>
-#include <linux/kref.h>
#include <linux/gpio/driver.h>
#include <linux/gpio/machine.h>
+#include <linux/gpio/property.h>
#include <linux/idr.h>
+#include <linux/kernel.h>
+#include <linux/kref.h>
#include <linux/module.h>
#include <linux/of.h>
-#include <linux/acpi.h>
-#include <linux/platform_device.h>
#include <linux/reset.h>
#include <linux/reset-controller.h>
#include <linux/slab.h>
@@ -25,9 +27,6 @@
static DEFINE_MUTEX(reset_list_mutex);
static LIST_HEAD(reset_controller_list);
-static DEFINE_MUTEX(reset_lookup_mutex);
-static LIST_HEAD(reset_lookup_list);
-
/* Protects reset_gpio_lookup_list */
static DEFINE_MUTEX(reset_gpio_lookup_mutex);
static LIST_HEAD(reset_gpio_lookup_list);
@@ -76,10 +75,12 @@ struct reset_control_array {
/**
* struct reset_gpio_lookup - lookup key for ad-hoc created reset-gpio devices
* @of_args: phandle to the reset controller with all the args like GPIO number
+ * @swnode: Software node containing the reference to the GPIO provider
* @list: list entry for the reset_gpio_lookup_list
*/
struct reset_gpio_lookup {
struct of_phandle_args of_args;
+ struct fwnode_handle *swnode;
struct list_head list;
};
@@ -190,33 +191,6 @@ int devm_reset_controller_register(struct device *dev,
}
EXPORT_SYMBOL_GPL(devm_reset_controller_register);
-/**
- * reset_controller_add_lookup - register a set of lookup entries
- * @lookup: array of reset lookup entries
- * @num_entries: number of entries in the lookup array
- */
-void reset_controller_add_lookup(struct reset_control_lookup *lookup,
- unsigned int num_entries)
-{
- struct reset_control_lookup *entry;
- unsigned int i;
-
- mutex_lock(&reset_lookup_mutex);
- for (i = 0; i < num_entries; i++) {
- entry = &lookup[i];
-
- if (!entry->dev_id || !entry->provider) {
- pr_warn("%s(): reset lookup entry badly specified, skipping\n",
- __func__);
- continue;
- }
-
- list_add_tail(&entry->list, &reset_lookup_list);
- }
- mutex_unlock(&reset_lookup_mutex);
-}
-EXPORT_SYMBOL_GPL(reset_controller_add_lookup);
-
static inline struct reset_control_array *
rstc_to_array(struct reset_control *rstc) {
return container_of(rstc, struct reset_control_array, base);
@@ -773,12 +747,19 @@ EXPORT_SYMBOL_GPL(reset_control_bulk_release);
static struct reset_control *
__reset_control_get_internal(struct reset_controller_dev *rcdev,
- unsigned int index, bool shared, bool acquired)
+ unsigned int index, enum reset_control_flags flags)
{
+ bool shared = flags & RESET_CONTROL_FLAGS_BIT_SHARED;
+ bool acquired = flags & RESET_CONTROL_FLAGS_BIT_ACQUIRED;
struct reset_control *rstc;
lockdep_assert_held(&reset_list_mutex);
+ /* Expect callers to filter out OPTIONAL and DEASSERTED bits */
+ if (WARN_ON(flags & ~(RESET_CONTROL_FLAGS_BIT_SHARED |
+ RESET_CONTROL_FLAGS_BIT_ACQUIRED)))
+ return ERR_PTR(-EINVAL);
+
list_for_each_entry(rstc, &rcdev->reset_control_head, list) {
if (rstc->id == index) {
/*
@@ -812,6 +793,7 @@ __reset_control_get_internal(struct reset_controller_dev *rcdev,
kref_init(&rstc->refcnt);
rstc->acquired = acquired;
rstc->shared = shared;
+ get_device(rcdev->dev);
return rstc;
}
@@ -826,6 +808,7 @@ static void __reset_control_release(struct kref *kref)
module_put(rstc->rcdev->owner);
list_del(&rstc->list);
+ put_device(rstc->rcdev->dev);
kfree(rstc);
}
@@ -839,56 +822,45 @@ static void __reset_control_put_internal(struct reset_control *rstc)
kref_put(&rstc->refcnt, __reset_control_release);
}
-static int __reset_add_reset_gpio_lookup(int id, struct device_node *np,
- unsigned int gpio,
- unsigned int of_flags)
+static void reset_gpio_aux_device_release(struct device *dev)
{
- const struct fwnode_handle *fwnode = of_fwnode_handle(np);
- unsigned int lookup_flags;
- const char *label_tmp;
-
- /*
- * Later we map GPIO flags between OF and Linux, however not all
- * constants from include/dt-bindings/gpio/gpio.h and
- * include/linux/gpio/machine.h match each other.
- */
- if (of_flags > GPIO_ACTIVE_LOW) {
- pr_err("reset-gpio code does not support GPIO flags %u for GPIO %u\n",
- of_flags, gpio);
- return -EINVAL;
- }
+ struct auxiliary_device *adev = to_auxiliary_dev(dev);
- struct gpio_device *gdev __free(gpio_device_put) = gpio_device_find_by_fwnode(fwnode);
- if (!gdev)
- return -EPROBE_DEFER;
-
- label_tmp = gpio_device_get_label(gdev);
- if (!label_tmp)
- return -EINVAL;
+ kfree(adev);
+}
- char *label __free(kfree) = kstrdup(label_tmp, GFP_KERNEL);
- if (!label)
- return -ENOMEM;
+static int reset_add_gpio_aux_device(struct device *parent,
+ struct fwnode_handle *swnode,
+ int id, void *pdata)
+{
+ struct auxiliary_device *adev;
+ int ret;
- /* Size: one lookup entry plus sentinel */
- struct gpiod_lookup_table *lookup __free(kfree) = kzalloc(struct_size(lookup, table, 2),
- GFP_KERNEL);
- if (!lookup)
+ adev = kzalloc(sizeof(*adev), GFP_KERNEL);
+ if (!adev)
return -ENOMEM;
- lookup->dev_id = kasprintf(GFP_KERNEL, "reset-gpio.%d", id);
- if (!lookup->dev_id)
- return -ENOMEM;
+ adev->id = id;
+ adev->name = "gpio";
+ adev->dev.parent = parent;
+ adev->dev.platform_data = pdata;
+ adev->dev.release = reset_gpio_aux_device_release;
+ device_set_node(&adev->dev, swnode);
- lookup_flags = GPIO_PERSISTENT;
- lookup_flags |= of_flags & GPIO_ACTIVE_LOW;
- lookup->table[0] = GPIO_LOOKUP(no_free_ptr(label), gpio, "reset",
- lookup_flags);
+ ret = auxiliary_device_init(adev);
+ if (ret) {
+ kfree(adev);
+ return ret;
+ }
- /* Not freed on success, because it is persisent subsystem data. */
- gpiod_add_lookup_table(no_free_ptr(lookup));
+ ret = __auxiliary_device_add(adev, "reset");
+ if (ret) {
+ auxiliary_device_uninit(adev);
+ kfree(adev);
+ return ret;
+ }
- return 0;
+ return ret;
}
/*
@@ -896,8 +868,10 @@ static int __reset_add_reset_gpio_lookup(int id, struct device_node *np,
*/
static int __reset_add_reset_gpio_device(const struct of_phandle_args *args)
{
+ struct property_entry properties[2] = { };
+ unsigned int offset, of_flags, lflags;
struct reset_gpio_lookup *rgpio_dev;
- struct platform_device *pdev;
+ struct device *parent;
int id, ret;
/*
@@ -916,20 +890,44 @@ static int __reset_add_reset_gpio_device(const struct of_phandle_args *args)
*/
lockdep_assert_not_held(&reset_list_mutex);
- mutex_lock(&reset_gpio_lookup_mutex);
+ offset = args->args[0];
+ of_flags = args->args[1];
+
+ /*
+ * Later we map GPIO flags between OF and Linux, however not all
+ * constants from include/dt-bindings/gpio/gpio.h and
+ * include/linux/gpio/machine.h match each other.
+ *
+ * FIXME: Find a better way of translating OF flags to GPIO lookup
+ * flags.
+ */
+ if (of_flags > GPIO_ACTIVE_LOW) {
+ pr_err("reset-gpio code does not support GPIO flags %u for GPIO %u\n",
+ of_flags, offset);
+ return -EINVAL;
+ }
+
+ struct gpio_device *gdev __free(gpio_device_put) =
+ gpio_device_find_by_fwnode(of_fwnode_handle(args->np));
+ if (!gdev)
+ return -EPROBE_DEFER;
+
+ guard(mutex)(&reset_gpio_lookup_mutex);
list_for_each_entry(rgpio_dev, &reset_gpio_lookup_list, list) {
if (args->np == rgpio_dev->of_args.np) {
if (of_phandle_args_equal(args, &rgpio_dev->of_args))
- goto out; /* Already on the list, done */
+ return 0; /* Already on the list, done */
}
}
+ lflags = GPIO_PERSISTENT | (of_flags & GPIO_ACTIVE_LOW);
+ parent = gpio_device_to_device(gdev);
+ properties[0] = PROPERTY_ENTRY_GPIO("reset-gpios", parent->fwnode, offset, lflags);
+
id = ida_alloc(&reset_gpio_ida, GFP_KERNEL);
- if (id < 0) {
- ret = id;
- goto err_unlock;
- }
+ if (id < 0)
+ return id;
/* Not freed on success, because it is persisent subsystem data. */
rgpio_dev = kzalloc(sizeof(*rgpio_dev), GFP_KERNEL);
@@ -938,11 +936,6 @@ static int __reset_add_reset_gpio_device(const struct of_phandle_args *args)
goto err_ida_free;
}
- ret = __reset_add_reset_gpio_lookup(id, args->np, args->args[0],
- args->args[1]);
- if (ret < 0)
- goto err_kfree;
-
rgpio_dev->of_args = *args;
/*
* We keep the device_node reference, but of_args.np is put at the end
@@ -950,28 +943,29 @@ static int __reset_add_reset_gpio_device(const struct of_phandle_args *args)
* Hold reference as long as rgpio_dev memory is valid.
*/
of_node_get(rgpio_dev->of_args.np);
- pdev = platform_device_register_data(NULL, "reset-gpio", id,
- &rgpio_dev->of_args,
- sizeof(rgpio_dev->of_args));
- ret = PTR_ERR_OR_ZERO(pdev);
+
+ rgpio_dev->swnode = fwnode_create_software_node(properties, NULL);
+ if (IS_ERR(rgpio_dev->swnode)) {
+ ret = PTR_ERR(rgpio_dev->swnode);
+ goto err_put_of_node;
+ }
+
+ ret = reset_add_gpio_aux_device(parent, rgpio_dev->swnode, id,
+ &rgpio_dev->of_args);
if (ret)
- goto err_put;
+ goto err_del_swnode;
list_add(&rgpio_dev->list, &reset_gpio_lookup_list);
-out:
- mutex_unlock(&reset_gpio_lookup_mutex);
-
return 0;
-err_put:
+err_del_swnode:
+ fwnode_remove_software_node(rgpio_dev->swnode);
+err_put_of_node:
of_node_put(rgpio_dev->of_args.np);
-err_kfree:
kfree(rgpio_dev);
err_ida_free:
ida_free(&reset_gpio_ida, id);
-err_unlock:
- mutex_unlock(&reset_gpio_lookup_mutex);
return ret;
}
@@ -999,8 +993,9 @@ static struct reset_controller_dev *__reset_find_rcdev(const struct of_phandle_a
struct reset_control *
__of_reset_control_get(struct device_node *node, const char *id, int index,
- bool shared, bool optional, bool acquired)
+ enum reset_control_flags flags)
{
+ bool optional = flags & RESET_CONTROL_FLAGS_BIT_OPTIONAL;
bool gpio_fallback = false;
struct reset_control *rstc;
struct reset_controller_dev *rcdev;
@@ -1064,8 +1059,10 @@ __of_reset_control_get(struct device_node *node, const char *id, int index,
goto out_unlock;
}
+ flags &= ~RESET_CONTROL_FLAGS_BIT_OPTIONAL;
+
/* reset_list_mutex also protects the rcdev's reset_control list */
- rstc = __reset_control_get_internal(rcdev, rstc_id, shared, acquired);
+ rstc = __reset_control_get_internal(rcdev, rstc_id, flags);
out_unlock:
mutex_unlock(&reset_list_mutex);
@@ -1076,92 +1073,31 @@ out_put:
}
EXPORT_SYMBOL_GPL(__of_reset_control_get);
-static struct reset_controller_dev *
-__reset_controller_by_name(const char *name)
-{
- struct reset_controller_dev *rcdev;
-
- lockdep_assert_held(&reset_list_mutex);
-
- list_for_each_entry(rcdev, &reset_controller_list, list) {
- if (!rcdev->dev)
- continue;
-
- if (!strcmp(name, dev_name(rcdev->dev)))
- return rcdev;
- }
-
- return NULL;
-}
-
-static struct reset_control *
-__reset_control_get_from_lookup(struct device *dev, const char *con_id,
- bool shared, bool optional, bool acquired)
-{
- const struct reset_control_lookup *lookup;
- struct reset_controller_dev *rcdev;
- const char *dev_id = dev_name(dev);
- struct reset_control *rstc = NULL;
-
- mutex_lock(&reset_lookup_mutex);
-
- list_for_each_entry(lookup, &reset_lookup_list, list) {
- if (strcmp(lookup->dev_id, dev_id))
- continue;
-
- if ((!con_id && !lookup->con_id) ||
- ((con_id && lookup->con_id) &&
- !strcmp(con_id, lookup->con_id))) {
- mutex_lock(&reset_list_mutex);
- rcdev = __reset_controller_by_name(lookup->provider);
- if (!rcdev) {
- mutex_unlock(&reset_list_mutex);
- mutex_unlock(&reset_lookup_mutex);
- /* Reset provider may not be ready yet. */
- return ERR_PTR(-EPROBE_DEFER);
- }
-
- rstc = __reset_control_get_internal(rcdev,
- lookup->index,
- shared, acquired);
- mutex_unlock(&reset_list_mutex);
- break;
- }
- }
-
- mutex_unlock(&reset_lookup_mutex);
-
- if (!rstc)
- return optional ? NULL : ERR_PTR(-ENOENT);
-
- return rstc;
-}
-
struct reset_control *__reset_control_get(struct device *dev, const char *id,
- int index, bool shared, bool optional,
- bool acquired)
+ int index, enum reset_control_flags flags)
{
+ bool shared = flags & RESET_CONTROL_FLAGS_BIT_SHARED;
+ bool acquired = flags & RESET_CONTROL_FLAGS_BIT_ACQUIRED;
+ bool optional = flags & RESET_CONTROL_FLAGS_BIT_OPTIONAL;
+
if (WARN_ON(shared && acquired))
return ERR_PTR(-EINVAL);
if (dev->of_node)
- return __of_reset_control_get(dev->of_node, id, index, shared,
- optional, acquired);
+ return __of_reset_control_get(dev->of_node, id, index, flags);
- return __reset_control_get_from_lookup(dev, id, shared, optional,
- acquired);
+ return optional ? NULL : ERR_PTR(-ENOENT);
}
EXPORT_SYMBOL_GPL(__reset_control_get);
int __reset_control_bulk_get(struct device *dev, int num_rstcs,
struct reset_control_bulk_data *rstcs,
- bool shared, bool optional, bool acquired)
+ enum reset_control_flags flags)
{
int ret, i;
for (i = 0; i < num_rstcs; i++) {
- rstcs[i].rstc = __reset_control_get(dev, rstcs[i].id, 0,
- shared, optional, acquired);
+ rstcs[i].rstc = __reset_control_get(dev, rstcs[i].id, 0, flags);
if (IS_ERR(rstcs[i].rstc)) {
ret = PTR_ERR(rstcs[i].rstc);
goto err;
@@ -1229,23 +1165,46 @@ static void devm_reset_control_release(struct device *dev, void *res)
reset_control_put(*(struct reset_control **)res);
}
+static void devm_reset_control_release_deasserted(struct device *dev, void *res)
+{
+ struct reset_control *rstc = *(struct reset_control **)res;
+
+ reset_control_assert(rstc);
+ reset_control_put(rstc);
+}
+
struct reset_control *
__devm_reset_control_get(struct device *dev, const char *id, int index,
- bool shared, bool optional, bool acquired)
+ enum reset_control_flags flags)
{
struct reset_control **ptr, *rstc;
+ bool deasserted = flags & RESET_CONTROL_FLAGS_BIT_DEASSERTED;
- ptr = devres_alloc(devm_reset_control_release, sizeof(*ptr),
+ ptr = devres_alloc(deasserted ? devm_reset_control_release_deasserted :
+ devm_reset_control_release, sizeof(*ptr),
GFP_KERNEL);
if (!ptr)
return ERR_PTR(-ENOMEM);
- rstc = __reset_control_get(dev, id, index, shared, optional, acquired);
+ flags &= ~RESET_CONTROL_FLAGS_BIT_DEASSERTED;
+
+ rstc = __reset_control_get(dev, id, index, flags);
if (IS_ERR_OR_NULL(rstc)) {
devres_free(ptr);
return rstc;
}
+ if (deasserted) {
+ int ret;
+
+ ret = reset_control_deassert(rstc);
+ if (ret) {
+ reset_control_put(rstc);
+ devres_free(ptr);
+ return ERR_PTR(ret);
+ }
+ }
+
*ptr = rstc;
devres_add(dev, ptr);
@@ -1265,24 +1224,45 @@ static void devm_reset_control_bulk_release(struct device *dev, void *res)
reset_control_bulk_put(devres->num_rstcs, devres->rstcs);
}
+static void devm_reset_control_bulk_release_deasserted(struct device *dev, void *res)
+{
+ struct reset_control_bulk_devres *devres = res;
+
+ reset_control_bulk_assert(devres->num_rstcs, devres->rstcs);
+ reset_control_bulk_put(devres->num_rstcs, devres->rstcs);
+}
+
int __devm_reset_control_bulk_get(struct device *dev, int num_rstcs,
struct reset_control_bulk_data *rstcs,
- bool shared, bool optional, bool acquired)
+ enum reset_control_flags flags)
{
struct reset_control_bulk_devres *ptr;
+ bool deasserted = flags & RESET_CONTROL_FLAGS_BIT_DEASSERTED;
int ret;
- ptr = devres_alloc(devm_reset_control_bulk_release, sizeof(*ptr),
+ ptr = devres_alloc(deasserted ? devm_reset_control_bulk_release_deasserted :
+ devm_reset_control_bulk_release, sizeof(*ptr),
GFP_KERNEL);
if (!ptr)
return -ENOMEM;
- ret = __reset_control_bulk_get(dev, num_rstcs, rstcs, shared, optional, acquired);
+ flags &= ~RESET_CONTROL_FLAGS_BIT_DEASSERTED;
+
+ ret = __reset_control_bulk_get(dev, num_rstcs, rstcs, flags);
if (ret < 0) {
devres_free(ptr);
return ret;
}
+ if (deasserted) {
+ ret = reset_control_bulk_deassert(num_rstcs, rstcs);
+ if (ret) {
+ reset_control_bulk_put(num_rstcs, rstcs);
+ devres_free(ptr);
+ return ret;
+ }
+ }
+
ptr->num_rstcs = num_rstcs;
ptr->rstcs = rstcs;
devres_add(dev, ptr);
@@ -1303,6 +1283,7 @@ EXPORT_SYMBOL_GPL(__devm_reset_control_bulk_get);
*/
int __device_reset(struct device *dev, bool optional)
{
+ enum reset_control_flags flags;
struct reset_control *rstc;
int ret;
@@ -1318,7 +1299,8 @@ int __device_reset(struct device *dev, bool optional)
}
#endif
- rstc = __reset_control_get(dev, NULL, 0, 0, optional, true);
+ flags = optional ? RESET_CONTROL_OPTIONAL_EXCLUSIVE : RESET_CONTROL_EXCLUSIVE;
+ rstc = __reset_control_get(dev, NULL, 0, flags);
if (IS_ERR(rstc))
return PTR_ERR(rstc);
@@ -1361,17 +1343,14 @@ static int of_reset_control_get_count(struct device_node *node)
* device node.
*
* @np: device node for the device that requests the reset controls array
- * @shared: whether reset controls are shared or not
- * @optional: whether it is optional to get the reset controls
- * @acquired: only one reset control may be acquired for a given controller
- * and ID
+ * @flags: whether reset controls are shared, optional, acquired
*
* Returns pointer to allocated reset_control on success or error on failure
*/
struct reset_control *
-of_reset_control_array_get(struct device_node *np, bool shared, bool optional,
- bool acquired)
+of_reset_control_array_get(struct device_node *np, enum reset_control_flags flags)
{
+ bool optional = flags & RESET_CONTROL_FLAGS_BIT_OPTIONAL;
struct reset_control_array *resets;
struct reset_control *rstc;
int num, i;
@@ -1386,8 +1365,7 @@ of_reset_control_array_get(struct device_node *np, bool shared, bool optional,
resets->num_rstcs = num;
for (i = 0; i < num; i++) {
- rstc = __of_reset_control_get(np, NULL, i, shared, optional,
- acquired);
+ rstc = __of_reset_control_get(np, NULL, i, flags);
if (IS_ERR(rstc))
goto err_rst;
resets->rstc[i] = rstc;
@@ -1412,8 +1390,7 @@ EXPORT_SYMBOL_GPL(of_reset_control_array_get);
* devm_reset_control_array_get - Resource managed reset control array get
*
* @dev: device that requests the list of reset controls
- * @shared: whether reset controls are shared or not
- * @optional: whether it is optional to get the reset controls
+ * @flags: whether reset controls are shared, optional, acquired
*
* The reset control array APIs are intended for a list of resets
* that just have to be asserted or deasserted, without any
@@ -1422,7 +1399,7 @@ EXPORT_SYMBOL_GPL(of_reset_control_array_get);
* Returns pointer to allocated reset_control on success or error on failure
*/
struct reset_control *
-devm_reset_control_array_get(struct device *dev, bool shared, bool optional)
+devm_reset_control_array_get(struct device *dev, enum reset_control_flags flags)
{
struct reset_control **ptr, *rstc;
@@ -1431,7 +1408,7 @@ devm_reset_control_array_get(struct device *dev, bool shared, bool optional)
if (!ptr)
return ERR_PTR(-ENOMEM);
- rstc = of_reset_control_array_get(dev->of_node, shared, optional, true);
+ rstc = of_reset_control_array_get(dev->of_node, flags);
if (IS_ERR_OR_NULL(rstc)) {
devres_free(ptr);
return rstc;
@@ -1444,31 +1421,6 @@ devm_reset_control_array_get(struct device *dev, bool shared, bool optional)
}
EXPORT_SYMBOL_GPL(devm_reset_control_array_get);
-static int reset_control_get_count_from_lookup(struct device *dev)
-{
- const struct reset_control_lookup *lookup;
- const char *dev_id;
- int count = 0;
-
- if (!dev)
- return -EINVAL;
-
- dev_id = dev_name(dev);
- mutex_lock(&reset_lookup_mutex);
-
- list_for_each_entry(lookup, &reset_lookup_list, list) {
- if (!strcmp(lookup->dev_id, dev_id))
- count++;
- }
-
- mutex_unlock(&reset_lookup_mutex);
-
- if (count == 0)
- count = -ENOENT;
-
- return count;
-}
-
/**
* reset_control_get_count - Count number of resets available with a device
*
@@ -1482,6 +1434,6 @@ int reset_control_get_count(struct device *dev)
if (dev->of_node)
return of_reset_control_get_count(dev->of_node);
- return reset_control_get_count_from_lookup(dev);
+ return -ENOENT;
}
EXPORT_SYMBOL_GPL(reset_control_get_count);