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()
314  * reset_control_reset - reset the controlled device
315  * @rstc: reset controller
317  * On a shared reset line the actual reset pulse is only triggered once for the
320  * Consumers must not use reset_control_(de)assert on shared reset lines when
323  * If rstc is NULL it is an optional reset and the function will just
339 	if (!rstc->rcdev->ops->reset)  in reset_control_reset()
353 	ret = rstc->rcdev->ops->reset(rstc->rcdev, rstc->id);  in reset_control_reset()
362  * reset_control_bulk_reset - reset the controlled devices in order
364  * @rstcs: array of struct reset_control_bulk_data with reset controls set
366  * Issue a reset on all provided reset controls, in order.
386  * reset_control_rearm - allow shared reset line to be re-triggered"
387  * @rstc: reset controller
389  * On a shared reset line the actual reset pulse is only triggered once for the
395  * Consumers must not use reset_control_(de)assert on shared reset lines when
426  * reset_control_assert - asserts the reset line
427  * @rstc: reset controller
429  * Calling this on an exclusive reset controller guarantees that the reset
430  * will be asserted. When called on a shared reset controller the line may
433  * For shared reset controls a driver cannot expect the hw's registers and
434  * internal state to be reset, but must be prepared for this to happen.
435  * Consumers must not use reset_control_reset on shared reset lines when
438  * If rstc is NULL it is an optional reset and the function will just
463 		 * Shared reset controls allow the reset line to be in any state  in reset_control_assert()
470 		 * If the reset controller does not implement .assert(), there  in reset_control_assert()
471 		 * is no way to guarantee that the reset line is asserted after  in reset_control_assert()
478 			WARN(1, "reset %s (ID: %u) is not acquired\n",  in reset_control_assert()
489  * reset_control_bulk_assert - asserts the reset lines in order
491  * @rstcs: array of struct reset_control_bulk_data with reset controls set
493  * Assert the reset lines for all provided reset controls, in order.
519  * reset_control_deassert - deasserts the reset line
520  * @rstc: reset controller
522  * After calling this function, the reset is guaranteed to be deasserted.
523  * Consumers must not use reset_control_reset on shared reset lines when
526  * If rstc is NULL it is an optional reset and the function will just
548 			WARN(1, "reset %s (ID: %u) is not acquired\n",  in reset_control_deassert()
555 	 * If the reset controller does not implement .deassert(), we assume  in reset_control_deassert()
556 	 * that it handles self-deasserting reset lines via .reset(). In that  in reset_control_deassert()
557 	 * case, the reset lines are deasserted by default. If that is not the  in reset_control_deassert()
558 	 * case, the reset controller driver should implement .deassert() and  in reset_control_deassert()
569  * reset_control_bulk_deassert - deasserts the reset lines in reverse order
571  * @rstcs: array of struct reset_control_bulk_data with reset controls set
573  * Deassert the reset lines for all provided reset controls, in reverse order.
600  * positive value if the reset line is asserted, or zero if the reset
601  * line is not asserted or if the desc is NULL (optional reset).
602  * @rstc: reset controller
620  * reset_control_acquire() - acquires a reset control for exclusive use
621  * @rstc: reset control
623  * This is used to explicitly acquire a reset control for exclusive use. Note
625  * second consumer to be able to control the reset, the first consumer has to
627  * reset_control_get_exclusive_released() to obtain an instance of the reset
628  * control. Such reset controls are not acquired by default.
630  * Consumers implementing shared access to an exclusive reset need to follow
632  * a reset they must acquire exclusive access using reset_control_acquire().
633  * After they are done operating the reset, they must release exclusive access
635  * access to the reset as long as another consumer hasn't released a reset.
676  * reset_control_bulk_acquire - acquires reset controls for exclusive use
678  * @rstcs: array of struct reset_control_bulk_data with reset controls set
680  * This is used to explicitly acquire reset controls requested with
706  * reset_control_release() - releases exclusive access to a reset control
707  * @rstc: reset control
709  * Releases exclusive access right to a reset control previously obtained by a
728  * reset_control_bulk_release() - releases exclusive access to reset controls
730  * @rstcs: array of struct reset_control_bulk_data with reset controls set
732  * Releases exclusive access right to reset controls previously obtained by a
760 			 * controlled reset line.  in __reset_control_get_internal()
827 						 "reset-names", id);  in __of_reset_control_get()
834 	ret = of_parse_phandle_with_args(node, "resets", "#reset-cells",  in __of_reset_control_get()
918 				/* Reset provider may not be ready yet. */  in __reset_control_get_from_lookup()
992  * reset_control_put - free the reset controller
993  * @rstc: reset controller
1012  * reset_control_bulk_put - free the reset controllers
1014  * @rstcs: array of struct reset_control_bulk_data with reset controls set
1096  * __device_reset - find reset controller associated with the device
1097  *                  and perform reset
1098  * @dev: device to be reset by the controller
1099  * @optional: whether it is optional to reset the device
1102  * This is useful for the common case of devices with single, dedicated reset
1123  * APIs to manage an array of reset controls.
1131  * Returns positive reset count on success, or error number on failure and
1141 	count = of_count_phandle_with_args(node, "resets", "#reset-cells");  in of_reset_control_get_count()
1149  * of_reset_control_array_get - Get a list of reset controls using
1152  * @np: device node for the device that requests the reset controls array
1153  * @shared: whether reset controls are shared or not
1154  * @optional: whether it is optional to get the reset controls
1155  * @acquired: only one reset control may be acquired for a given controller
1201  * devm_reset_control_array_get - Resource managed reset control array get
1203  * @dev: device that requests the list of reset controls
1204  * @shared: whether reset controls are shared or not
1205  * @optional: whether it is optional to get the reset controls
1207  * The reset control array APIs are intended for a list of resets
1266  * Returns positive reset count on success, or error number on failure and