+/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (c) 2016, NVIDIA CORPORATION.
- *
- * SPDX-License-Identifier: GPL-2.0
*/
#ifndef _RESET_H
#define _RESET_H
-#include <linux/errno.h>
+#include <dm/ofnode.h>
+#include <linux/err.h>
/**
* A reset is a hardware signal indicating that a HW module (or IP block, or
*
* @dev: The device which implements the reset signal.
* @id: The reset signal ID within the provider.
+ * @data: An optional data field for scenarios where a single integer ID is not
+ * sufficient. If used, it can be populated through an .of_xlate op and
+ * processed during the various reset ops.
+ * @polarity: An optional polarity field for drivers that support
+ * different reset polarities.
*
- * Currently, the reset API assumes that a single integer ID is enough to
- * identify and configure any reset signal for any reset provider. If this
- * assumption becomes invalid in the future, the struct could be expanded to
+ * Should additional information to identify and configure any reset signal
+ * for any provider be required in the future, the struct could be expanded to
* either (a) add more fields to allow reset providers to store additional
* information, or (b) replace the id field with an opaque pointer, which the
* provider would dynamically allocated during its .of_xlate op, and process
struct reset_ctl {
struct udevice *dev;
/*
- * Written by of_xlate. We assume a single id is enough for now. In the
- * future, we might add more fields here.
+ * Written by of_xlate. In the future, we might add more fields here.
*/
unsigned long id;
+ unsigned long data;
+ unsigned long polarity;
};
-#ifdef CONFIG_DM_RESET
+/**
+ * struct reset_ctl_bulk - A handle to (allowing control of) a bulk of reset
+ * signals.
+ *
+ * Clients provide storage for the reset control bulk. The content of the
+ * structure is managed solely by the reset API. A reset control bulk struct is
+ * initialized by "get"ing the reset control bulk struct.
+ * The reset control bulk struct is passed to all other bulk reset APIs to apply
+ * the API to all the reset signals in the bulk struct.
+ *
+ * @resets: An array of reset signal handles handles.
+ * @count: The number of reset signal handles in the reset array.
+ */
+struct reset_ctl_bulk {
+ struct reset_ctl *resets;
+ unsigned int count;
+};
+
+#if CONFIG_IS_ENABLED(DM_RESET)
+
+/**
+ * devm_reset_control_get - resource managed reset_get_by_name()
+ * @dev: device to be reset by the controller
+ * @id: reset line name
+ *
+ * Managed reset_get_by_name(). For reset controllers returned
+ * from this function, reset_free() is called automatically on driver
+ * detach.
+ *
+ * Returns a struct reset_ctl or IS_ERR() condition containing errno.
+ */
+struct reset_ctl *devm_reset_control_get(struct udevice *dev, const char *id);
+
+/**
+ * devm_reset_control_get_optional - resource managed reset_get_by_name() that
+ * can fail
+ * @dev: The client device.
+ * @id: reset line name
+ *
+ * Managed reset_get_by_name(). For reset controllers returned
+ * from this function, reset_free() is called automatically on driver
+ * detach.
+ *
+ * Returns a struct reset_ctl or a dummy reset controller if it failed.
+ */
+struct reset_ctl *devm_reset_control_get_optional(struct udevice *dev,
+ const char *id);
+
+/**
+ * devm_reset_control_get - resource managed reset_get_by_index()
+ * @dev: The client device.
+ * @index: The index of the reset signal to request, within the client's
+ * list of reset signals.
+ *
+ * Managed reset_get_by_index(). For reset controllers returned
+ * from this function, reset_free() is called automatically on driver
+ * detach.
+ *
+ * Returns a struct reset_ctl or IS_ERR() condition containing errno.
+ */
+struct reset_ctl *devm_reset_control_get_by_index(struct udevice *dev,
+ int index);
+
+/**
+ * devm_reset_bulk_get - resource managed reset_get_bulk()
+ * @dev: device to be reset by the controller
+ *
+ * Managed reset_get_bulk(). For reset controllers returned
+ * from this function, reset_free() is called automatically on driver
+ * detach.
+ *
+ * Returns a struct reset_ctl or IS_ERR() condition containing errno.
+ */
+struct reset_ctl_bulk *devm_reset_bulk_get(struct udevice *dev);
+
+/**
+ * devm_reset_bulk_get_optional - resource managed reset_get_bulk() that
+ * can fail
+ * @dev: The client device.
+ *
+ * Managed reset_get_bulk(). For reset controllers returned
+ * from this function, reset_free() is called automatically on driver
+ * detach.
+ *
+ * Returns a struct reset_ctl or NULL if it failed.
+ */
+struct reset_ctl_bulk *devm_reset_bulk_get_optional(struct udevice *dev);
+
+/**
+ * devm_reset_bulk_get_by_node - resource managed reset_get_bulk()
+ * @dev: device to be reset by the controller
+ * @node: ofnode where the "resets" property is. Usually a sub-node of
+ * the dev's node.
+ *
+ * see devm_reset_bulk_get()
+ */
+struct reset_ctl_bulk *devm_reset_bulk_get_by_node(struct udevice *dev,
+ ofnode node);
+
+/**
+ * devm_reset_bulk_get_optional_by_node - resource managed reset_get_bulk()
+ * that can fail
+ * @dev: device to be reset by the controller
+ * @node: ofnode where the "resets" property is. Usually a sub-node of
+ * the dev's node.
+ *
+ * see devm_reset_bulk_get_optional()
+ */
+struct reset_ctl_bulk *devm_reset_bulk_get_optional_by_node(struct udevice *dev,
+ ofnode node);
+
/**
* reset_get_by_index - Get/request a reset signal by integer index.
*
* @index: The index of the reset signal to request, within the client's
* list of reset signals.
* @reset_ctl A pointer to a reset control struct to initialize.
- * @return 0 if OK, or a negative error code.
+ * Return: 0 if OK, or a negative error code.
*/
int reset_get_by_index(struct udevice *dev, int index,
struct reset_ctl *reset_ctl);
/**
+ * reset_get_by_index_nodev - Get/request a reset signal by integer index
+ * without a device.
+ *
+ * This is a version of reset_get_by_index() that does not use a device.
+ *
+ * @node: The client ofnode.
+ * @index: The index of the reset signal to request, within the client's
+ * list of reset signals.
+ * @reset_ctl A pointer to a reset control struct to initialize.
+ * Return: 0 if OK, or a negative error code.
+ */
+int reset_get_by_index_nodev(ofnode node, int index,
+ struct reset_ctl *reset_ctl);
+
+/**
+ * reset_get_bulk - Get/request all reset signals of a device.
+ *
+ * This looks up and requests all reset signals of the client device; each
+ * device is assumed to have n reset signals associated with it somehow,
+ * and this function finds and requests all of them in a separate structure.
+ * The mapping of client device reset signals indices to provider reset signals
+ * may be via device-tree properties, board-provided mapping tables, or some
+ * other mechanism.
+ *
+ * @dev: The client device.
+ * @bulk A pointer to a reset control bulk struct to initialize.
+ * Return: 0 if OK, or a negative error code.
+ */
+int reset_get_bulk(struct udevice *dev, struct reset_ctl_bulk *bulk);
+
+/**
* reset_get_by_name - Get/request a reset signal by name.
*
* This looks up and requests a reset signal. The name is relative to the
* @name: The name of the reset signal to request, within the client's
* list of reset signals.
* @reset_ctl: A pointer to a reset control struct to initialize.
- * @return 0 if OK, or a negative error code.
+ * Return: 0 if OK, or a negative error code.
*/
int reset_get_by_name(struct udevice *dev, const char *name,
struct reset_ctl *reset_ctl);
*
* @reset_ctl: A reset control struct.
*
- * @return 0 if OK, or a negative error code.
+ * Return: 0 if OK, or a negative error code.
*/
int reset_request(struct reset_ctl *reset_ctl);
*
* @reset_ctl: A reset control struct that was previously successfully
* requested by reset_get_by_*().
- * @return 0 if OK, or a negative error code.
+ * Return: 0 if OK, or a negative error code.
*/
int reset_free(struct reset_ctl *reset_ctl);
*
* @reset_ctl: A reset control struct that was previously successfully
* requested by reset_get_by_*().
- * @return 0 if OK, or a negative error code.
+ * Return: 0 if OK, or a negative error code.
*/
int reset_assert(struct reset_ctl *reset_ctl);
/**
+ * reset_assert_bulk - Assert all reset signals in a reset control bulk struct.
+ *
+ * This function will assert the specified reset signals in a reset control
+ * bulk struct, thus resetting the affected HW module(s). Depending on the
+ * reset controller hardware, the reset signals will either stay asserted
+ * until reset_deassert_bulk() is called, or the hardware may autonomously
+ * clear the reset signals itself.
+ *
+ * @bulk: A reset control bulk struct that was previously successfully
+ * requested by reset_get_bulk().
+ * Return: 0 if OK, or a negative error code.
+ */
+int reset_assert_bulk(struct reset_ctl_bulk *bulk);
+
+/**
* reset_deassert - Deassert a reset signal.
*
* This function will deassert the specified reset signal, thus releasing the
*
* @reset_ctl: A reset control struct that was previously successfully
* requested by reset_get_by_*().
- * @return 0 if OK, or a negative error code.
+ * Return: 0 if OK, or a negative error code.
*/
int reset_deassert(struct reset_ctl *reset_ctl);
+/**
+ * reset_deassert_bulk - Deassert all reset signals in a reset control bulk
+ * struct.
+ *
+ * This function will deassert the specified reset signals in a reset control
+ * bulk struct, thus releasing the affected HW modules() from reset, and
+ * allowing them to continue normal operation.
+ *
+ * @bulk: A reset control bulk struct that was previously successfully
+ * requested by reset_get_bulk().
+ * Return: 0 if OK, or a negative error code.
+ */
+int reset_deassert_bulk(struct reset_ctl_bulk *bulk);
+
+/**
+ * rst_status - Check reset signal status.
+ *
+ * @reset_ctl: The reset signal to check.
+ * Return: 0 if deasserted, positive if asserted, or a negative
+ * error code.
+ */
+int reset_status(struct reset_ctl *reset_ctl);
+
+/**
+ * reset_release_all - Assert/Free an array of previously requested resets.
+ *
+ * For each reset contained in the reset array, this function will check if
+ * reset has been previously requested and then will assert and free it.
+ *
+ * @reset_ctl: A reset struct array that was previously successfully
+ * requested by reset_get_by_*().
+ * @count Number of reset contained in the array
+ * Return: 0 if OK, or a negative error code.
+ */
+int reset_release_all(struct reset_ctl *reset_ctl, int count);
+
+/**
+ * reset_release_bulk - Assert/Free an array of previously requested reset
+ * signals in a reset control bulk struct.
+ *
+ * For each reset contained in the reset control bulk struct, this function
+ * will check if reset has been previously requested and then will assert
+ * and free it.
+ *
+ * @bulk: A reset control bulk struct that was previously successfully
+ * requested by reset_get_bulk().
+ * Return: 0 if OK, or a negative error code.
+ */
+static inline int reset_release_bulk(struct reset_ctl_bulk *bulk)
+{
+ return reset_release_all(bulk->resets, bulk->count);
+}
+
#else
+static inline struct reset_ctl *devm_reset_control_get(struct udevice *dev,
+ const char *id)
+{
+ return ERR_PTR(-ENOTSUPP);
+}
+
+static inline struct reset_ctl *devm_reset_control_get_optional(struct udevice *dev,
+ const char *id)
+{
+ return NULL;
+}
+
+static inline struct reset_ctl *devm_reset_control_get_by_index(struct udevice *dev,
+ int index)
+{
+ return ERR_PTR(-ENOTSUPP);
+}
+
+static inline struct reset_ctl_bulk *devm_reset_bulk_get(struct udevice *dev)
+{
+ return ERR_PTR(-ENOTSUPP);
+}
+
+static inline struct reset_ctl_bulk *devm_reset_bulk_get_optional(struct udevice *dev)
+{
+ return NULL;
+}
+
+static inline struct reset_ctl_bulk *devm_reset_bulk_get_by_node(struct udevice *dev,
+ ofnode node)
+{
+ return ERR_PTR(-ENOTSUPP);
+}
+
+static inline struct reset_ctl_bulk *devm_reset_bulk_get_optional_by_node(struct udevice *dev,
+ ofnode node)
+{
+ return NULL;
+}
+
static inline int reset_get_by_index(struct udevice *dev, int index,
struct reset_ctl *reset_ctl)
{
return -ENOTSUPP;
}
+static inline int reset_get_bulk(struct udevice *dev,
+ struct reset_ctl_bulk *bulk)
+{
+ return -ENOTSUPP;
+}
+
static inline int reset_get_by_name(struct udevice *dev, const char *name,
struct reset_ctl *reset_ctl)
{
return 0;
}
+static inline int reset_assert_bulk(struct reset_ctl_bulk *bulk)
+{
+ return 0;
+}
+
static inline int reset_deassert(struct reset_ctl *reset_ctl)
{
return 0;
}
+
+static inline int reset_deassert_bulk(struct reset_ctl_bulk *bulk)
+{
+ return 0;
+}
+
+static inline int reset_status(struct reset_ctl *reset_ctl)
+{
+ return -ENOTSUPP;
+}
+
+static inline int reset_release_all(struct reset_ctl *reset_ctl, int count)
+{
+ return 0;
+}
+
+static inline int reset_release_bulk(struct reset_ctl_bulk *bulk)
+{
+ return 0;
+}
#endif
+/**
+ * reset_valid() - check if reset is valid
+ *
+ * @reset_ctl: the reset to check
+ * Return: TRUE if valid, or FALSE
+ */
+static inline bool reset_valid(struct reset_ctl *reset_ctl)
+{
+ return !!reset_ctl->dev;
+}
+
#endif