3  * Reset Controller framework
15 #include <linux/reset.h>
16 #include <linux/reset-controller.h>
26  * struct reset_control - a reset control
27  * @rcdev: a pointer to the reset controller device
28  *         this reset control belongs to
29  * @list: list entry for the rcdev's reset controller list
30  * @id: ID of the reset controller in the reset
35  * @array: Is this an array of reset controls (1)?
36  * @deassert_count: Number of times this reset line has been deasserted
37  * @triggered_count: Number of times this reset line has been reset. Currently
54  * struct reset_control_array - an array of reset controls
55  * @base: reset control for compatibility with reset control API functions
56  * @num_rstcs: number of reset controls
57  * @rstc: array of reset controls
77  * of_reset_simple_xlate - translate reset_spec to the reset line number
78  * @rcdev: a pointer to the reset controller device
79  * @reset_spec: reset line specifier as found in the device tree
82  * :c:type:`reset_controller_dev` is not set. It is useful for all reset
83  * controllers with 1:1 mapping, where reset lines can be indexed by number
96  * reset_controller_register - register a reset controller device
97  * @rcdev: a pointer to the initialized reset controller device
117  * reset_controller_unregister - unregister a reset controller device
118  * @rcdev: a pointer to the reset controller device
135  * @dev: device that is registering this reset controller
136  * @rcdev: a pointer to the initialized reset controller device
138  * Managed reset_controller_register(). For reset controllers registered by
168  * @lookup: array of reset lookup entries
182 			pr_warn("%s(): reset lookup entry badly specified, skipping\n",  in reset_controller_add_lookup()
281  * reset_control_reset - reset the controlled device
282  * @rstc: reset controller
284  * On a shared reset line the actual reset pulse is only triggered once for the
287  * Consumers must not use reset_control_(de)assert on shared reset lines when
290  * If rstc is NULL it is an optional reset and the function will just
306 	if (!rstc->rcdev->ops->reset)  in reset_control_reset()
320 	ret = rstc->rcdev->ops->reset(rstc->rcdev, rstc->id);  in reset_control_reset()
329  * reset_control_assert - asserts the reset line
330  * @rstc: reset controller
332  * Calling this on an exclusive reset controller guarantees that the reset
333  * will be asserted. When called on a shared reset controller the line may
336  * For shared reset controls a driver cannot expect the hw's registers and
337  * internal state to be reset, but must be prepared for this to happen.
338  * Consumers must not use reset_control_reset on shared reset lines when
341  * If rstc is NULL it is an optional reset and the function will just
366 		 * Shared reset controls allow the reset line to be in any state  in reset_control_assert()
373 		 * If the reset controller does not implement .assert(), there  in reset_control_assert()
374 		 * is no way to guarantee that the reset line is asserted after  in reset_control_assert()
381 			WARN(1, "reset %s (ID: %u) is not acquired\n",  in reset_control_assert()
392  * reset_control_deassert - deasserts the reset line
393  * @rstc: reset controller
395  * After calling this function, the reset is guaranteed to be deasserted.
396  * Consumers must not use reset_control_reset on shared reset lines when
399  * If rstc is NULL it is an optional reset and the function will just
421 			WARN(1, "reset %s (ID: %u) is not acquired\n",  in reset_control_deassert()
428 	 * If the reset controller does not implement .deassert(), we assume  in reset_control_deassert()
429 	 * that it handles self-deasserting reset lines via .reset(). In that  in reset_control_deassert()
430 	 * case, the reset lines are deasserted by default. If that is not the  in reset_control_deassert()
431 	 * case, the reset controller driver should implement .deassert() and  in reset_control_deassert()
443  * positive value if the reset line is asserted, or zero if the reset
444  * line is not asserted or if the desc is NULL (optional reset).
445  * @rstc: reset controller
463  * reset_control_acquire() - acquires a reset control for exclusive use
464  * @rstc: reset control
466  * This is used to explicitly acquire a reset control for exclusive use. Note
468  * second consumer to be able to control the reset, the first consumer has to
470  * reset_control_get_exclusive_released() to obtain an instance of the reset
471  * control. Such reset controls are not acquired by default.
473  * Consumers implementing shared access to an exclusive reset need to follow
475  * a reset they must acquire exclusive access using reset_control_acquire().
476  * After they are done operating the reset, they must release exclusive access
478  * access to the reset as long as another consumer hasn't released a reset.
519  * reset_control_release() - releases exclusive access to a reset control
520  * @rstc: reset control
522  * Releases exclusive access right to a reset control previously obtained by a
553 			 * controlled reset line.  in __reset_control_get_internal()
620 						 "reset-names", id);  in __of_reset_control_get()
627 	ret = of_parse_phandle_with_args(node, "resets", "#reset-cells",  in __of_reset_control_get()
711 				/* Reset provider may not be ready yet. */  in __reset_control_get_from_lookup()
759  * reset_control_put - free the reset controller
760  * @rstc: reset controller
808  * device_reset - find reset controller associated with the device
809  *                and perform reset
810  * @dev: device to be reset by the controller
811  * @optional: whether it is optional to reset the device
814  * This is useful for the common case of devices with single, dedicated reset
835  * APIs to manage an array of reset controls.
843  * Returns positive reset count on success, or error number on failure and
853 	count = of_count_phandle_with_args(node, "resets", "#reset-cells");  in of_reset_control_get_count()
861  * of_reset_control_array_get - Get a list of reset controls using
864  * @np: device node for the device that requests the reset controls array
865  * @shared: whether reset controls are shared or not
866  * @optional: whether it is optional to get the reset controls
867  * @acquired: only one reset control may be acquired for a given controller
913  * devm_reset_control_array_get - Resource managed reset control array get
915  * @dev: device that requests the list of reset controls
916  * @shared: whether reset controls are shared or not
917  * @optional: whether it is optional to get the reset controls
919  * The reset control array APIs are intended for a list of resets
978  * Returns positive reset count on success, or error number on failure and