unsigned int id;
struct kref refcnt;
bool shared;
+ bool array;
atomic_t deassert_count;
atomic_t triggered_count;
};
/**
+ * struct reset_control_array - an array of reset controls
+ * @base: reset control for compatibility with reset control API functions
+ * @num_rstcs: number of reset controls
+ * @rstc: array of reset controls
+ */
+struct reset_control_array {
+ struct reset_control base;
+ unsigned int num_rstcs;
+ struct reset_control *rstc[];
+};
+
+/**
* of_reset_simple_xlate - translate reset_spec to the reset line number
* @rcdev: a pointer to the reset controller device
* @reset_spec: reset line specifier as found in the device tree
}
EXPORT_SYMBOL_GPL(devm_reset_controller_register);
+static inline struct reset_control_array *
+rstc_to_array(struct reset_control *rstc) {
+ return container_of(rstc, struct reset_control_array, base);
+}
+
+static int reset_control_array_reset(struct reset_control_array *resets)
+{
+ int ret, i;
+
+ for (i = 0; i < resets->num_rstcs; i++) {
+ ret = reset_control_reset(resets->rstc[i]);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static int reset_control_array_assert(struct reset_control_array *resets)
+{
+ int ret, i;
+
+ for (i = 0; i < resets->num_rstcs; i++) {
+ ret = reset_control_assert(resets->rstc[i]);
+ if (ret)
+ goto err;
+ }
+
+ return 0;
+
+err:
+ while (i--)
+ reset_control_deassert(resets->rstc[i]);
+ return ret;
+}
+
+static int reset_control_array_deassert(struct reset_control_array *resets)
+{
+ int ret, i;
+
+ for (i = 0; i < resets->num_rstcs; i++) {
+ ret = reset_control_deassert(resets->rstc[i]);
+ if (ret)
+ goto err;
+ }
+
+ return 0;
+
+err:
+ while (i--)
+ reset_control_assert(resets->rstc[i]);
+ return ret;
+}
+
+static inline bool reset_control_is_array(struct reset_control *rstc)
+{
+ return rstc->array;
+}
+
/**
* reset_control_reset - reset the controlled device
* @rstc: reset controller
if (WARN_ON(IS_ERR(rstc)))
return -EINVAL;
+ if (reset_control_is_array(rstc))
+ return reset_control_array_reset(rstc_to_array(rstc));
+
if (!rstc->rcdev->ops->reset)
return -ENOTSUPP;
if (WARN_ON(IS_ERR(rstc)))
return -EINVAL;
- if (!rstc->rcdev->ops->assert)
- return -ENOTSUPP;
+ if (reset_control_is_array(rstc))
+ return reset_control_array_assert(rstc_to_array(rstc));
if (rstc->shared) {
if (WARN_ON(atomic_read(&rstc->triggered_count) != 0))
if (atomic_dec_return(&rstc->deassert_count) != 0)
return 0;
+
+ /*
+ * Shared reset controls allow the reset line to be in any state
+ * after this call, so doing nothing is a valid option.
+ */
+ if (!rstc->rcdev->ops->assert)
+ return 0;
+ } else {
+ /*
+ * If the reset controller does not implement .assert(), there
+ * is no way to guarantee that the reset line is asserted after
+ * this call.
+ */
+ if (!rstc->rcdev->ops->assert)
+ return -ENOTSUPP;
}
return rstc->rcdev->ops->assert(rstc->rcdev, rstc->id);
if (WARN_ON(IS_ERR(rstc)))
return -EINVAL;
- if (!rstc->rcdev->ops->deassert)
- return -ENOTSUPP;
+ if (reset_control_is_array(rstc))
+ return reset_control_array_deassert(rstc_to_array(rstc));
if (rstc->shared) {
if (WARN_ON(atomic_read(&rstc->triggered_count) != 0))
return 0;
}
+ /*
+ * If the reset controller does not implement .deassert(), we assume
+ * that it handles self-deasserting reset lines via .reset(). In that
+ * case, the reset lines are deasserted by default. If that is not the
+ * case, the reset controller driver should implement .deassert() and
+ * return -ENOTSUPP.
+ */
+ if (!rstc->rcdev->ops->deassert)
+ return 0;
+
return rstc->rcdev->ops->deassert(rstc->rcdev, rstc->id);
}
EXPORT_SYMBOL_GPL(reset_control_deassert);
if (!rstc)
return 0;
- if (WARN_ON(IS_ERR(rstc)))
+ if (WARN_ON(IS_ERR(rstc)) || reset_control_is_array(rstc))
return -EINVAL;
if (rstc->rcdev->ops->status)
}
EXPORT_SYMBOL_GPL(__reset_control_get);
+static void reset_control_array_put(struct reset_control_array *resets)
+{
+ int i;
+
+ mutex_lock(&reset_list_mutex);
+ for (i = 0; i < resets->num_rstcs; i++)
+ __reset_control_put_internal(resets->rstc[i]);
+ mutex_unlock(&reset_list_mutex);
+}
+
/**
* reset_control_put - free the reset controller
* @rstc: reset controller
if (IS_ERR_OR_NULL(rstc))
return;
+ if (reset_control_is_array(rstc)) {
+ reset_control_array_put(rstc_to_array(rstc));
+ return;
+ }
+
mutex_lock(&reset_list_mutex);
__reset_control_put_internal(rstc);
mutex_unlock(&reset_list_mutex);
* device_reset - find reset controller associated with the device
* and perform reset
* @dev: device to be reset by the controller
+ * @optional: whether it is optional to reset the device
*
- * Convenience wrapper for reset_control_get() and reset_control_reset().
+ * Convenience wrapper for __reset_control_get() and reset_control_reset().
* This is useful for the common case of devices with single, dedicated reset
* lines.
*/
-int device_reset(struct device *dev)
+int __device_reset(struct device *dev, bool optional)
{
struct reset_control *rstc;
int ret;
- rstc = reset_control_get(dev, NULL);
+ rstc = __reset_control_get(dev, NULL, 0, 0, optional);
if (IS_ERR(rstc))
return PTR_ERR(rstc);
return ret;
}
-EXPORT_SYMBOL_GPL(device_reset);
+EXPORT_SYMBOL_GPL(__device_reset);
+
+/**
+ * APIs to manage an array of reset controls.
+ */
+/**
+ * of_reset_control_get_count - Count number of resets available with a device
+ *
+ * @node: device node that contains 'resets'.
+ *
+ * Returns positive reset count on success, or error number on failure and
+ * on count being zero.
+ */
+static int of_reset_control_get_count(struct device_node *node)
+{
+ int count;
+
+ if (!node)
+ return -EINVAL;
+
+ count = of_count_phandle_with_args(node, "resets", "#reset-cells");
+ if (count == 0)
+ count = -ENOENT;
+
+ return count;
+}
+
+/**
+ * of_reset_control_array_get - Get a list of reset controls using
+ * 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
+ *
+ * Returns pointer to allocated reset_control_array on success or
+ * error on failure
+ */
+struct reset_control *
+of_reset_control_array_get(struct device_node *np, bool shared, bool optional)
+{
+ struct reset_control_array *resets;
+ struct reset_control *rstc;
+ int num, i;
+
+ num = of_reset_control_get_count(np);
+ if (num < 0)
+ return optional ? NULL : ERR_PTR(num);
+
+ resets = kzalloc(sizeof(*resets) + sizeof(resets->rstc[0]) * num,
+ GFP_KERNEL);
+ if (!resets)
+ return ERR_PTR(-ENOMEM);
+
+ for (i = 0; i < num; i++) {
+ rstc = __of_reset_control_get(np, NULL, i, shared, optional);
+ if (IS_ERR(rstc))
+ goto err_rst;
+ resets->rstc[i] = rstc;
+ }
+ resets->num_rstcs = num;
+ resets->base.array = true;
+
+ return &resets->base;
+
+err_rst:
+ mutex_lock(&reset_list_mutex);
+ while (--i >= 0)
+ __reset_control_put_internal(resets->rstc[i]);
+ mutex_unlock(&reset_list_mutex);
+
+ kfree(resets);
+
+ return rstc;
+}
+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
+ *
+ * The reset control array APIs are intended for a list of resets
+ * that just have to be asserted or deasserted, without any
+ * requirements on the order.
+ *
+ * Returns pointer to allocated reset_control_array on success or
+ * error on failure
+ */
+struct reset_control *
+devm_reset_control_array_get(struct device *dev, bool shared, bool optional)
+{
+ struct reset_control **devres;
+ struct reset_control *rstc;
+
+ devres = devres_alloc(devm_reset_control_release, sizeof(*devres),
+ GFP_KERNEL);
+ if (!devres)
+ return ERR_PTR(-ENOMEM);
+
+ rstc = of_reset_control_array_get(dev->of_node, shared, optional);
+ if (IS_ERR(rstc)) {
+ devres_free(devres);
+ return rstc;
+ }
+
+ *devres = rstc;
+ devres_add(dev, devres);
+
+ return rstc;
+}
+EXPORT_SYMBOL_GPL(devm_reset_control_array_get);
projects / platform / kernel / linux-exynos.git / blobdiff