mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-28 07:13:34 +00:00
6691dffab0
The reset framework only supports device-tree. There are some platforms
however, which need to use it even in legacy, board-file based mode.
An example of such architecture is the DaVinci family of SoCs which
supports both device tree and legacy boot modes and we don't want to
introduce any regressions.
We're currently working on converting the platform from its hand-crafted
clock API to using the common clock framework. Part of the overhaul will
be representing the chip's power sleep controller's reset lines using
the reset framework.
This changeset extends the core reset code with a new reset lookup
entry structure. It contains data allowing the reset core to associate
reset lines with devices by comparing the dev_id and con_id strings.
It also provides a function allowing drivers to register lookup entries
with the framework.
The new lookup function is only called as a fallback in case the
of_node field is NULL and doesn't change anything for current users.
Tested with a dummy reset driver with several lookup entries.
An example lookup table registration from a driver can be found below:
static struct reset_control_lookup foobar_reset_lookup[] = {
RESET_LOOKUP("foo.0", "foo", 15),
RESET_LOOKUP("bar.0", NULL, 5),
};
foobar_probe()
{
...
reset_controller_add_lookup(&rcdev, foobar_reset_lookup,
ARRAY_SIZE(foobar_reset_lookup));
...
}
Cc: Sekhar Nori <nsekhar@ti.com>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: David Lechner <david@lechnology.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
89 lines
2.9 KiB
C
89 lines
2.9 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _LINUX_RESET_CONTROLLER_H_
|
|
#define _LINUX_RESET_CONTROLLER_H_
|
|
|
|
#include <linux/list.h>
|
|
|
|
struct reset_controller_dev;
|
|
|
|
/**
|
|
* struct reset_control_ops
|
|
*
|
|
* @reset: for self-deasserting resets, does all necessary
|
|
* things to reset the device
|
|
* @assert: manually assert the reset line, if supported
|
|
* @deassert: manually deassert the reset line, if supported
|
|
* @status: return the status of the reset line, if supported
|
|
*/
|
|
struct reset_control_ops {
|
|
int (*reset)(struct reset_controller_dev *rcdev, unsigned long id);
|
|
int (*assert)(struct reset_controller_dev *rcdev, unsigned long id);
|
|
int (*deassert)(struct reset_controller_dev *rcdev, unsigned long id);
|
|
int (*status)(struct reset_controller_dev *rcdev, unsigned long id);
|
|
};
|
|
|
|
struct module;
|
|
struct device_node;
|
|
struct of_phandle_args;
|
|
|
|
/**
|
|
* struct reset_control_lookup - represents a single lookup entry
|
|
*
|
|
* @list: internal list of all reset lookup entries
|
|
* @rcdev: reset controller device controlling this reset line
|
|
* @index: ID of the reset controller in the reset controller device
|
|
* @dev_id: name of the device associated with this reset line
|
|
* @con_id name of the reset line (can be NULL)
|
|
*/
|
|
struct reset_control_lookup {
|
|
struct list_head list;
|
|
struct reset_controller_dev *rcdev;
|
|
unsigned int index;
|
|
const char *dev_id;
|
|
const char *con_id;
|
|
};
|
|
|
|
#define RESET_LOOKUP(_dev_id, _con_id, _index) \
|
|
{ \
|
|
.dev_id = _dev_id, \
|
|
.con_id = _con_id, \
|
|
.index = _index, \
|
|
}
|
|
|
|
/**
|
|
* struct reset_controller_dev - reset controller entity that might
|
|
* provide multiple reset controls
|
|
* @ops: a pointer to device specific struct reset_control_ops
|
|
* @owner: kernel module of the reset controller driver
|
|
* @list: internal list of reset controller devices
|
|
* @reset_control_head: head of internal list of requested reset controls
|
|
* @of_node: corresponding device tree node as phandle target
|
|
* @of_reset_n_cells: number of cells in reset line specifiers
|
|
* @of_xlate: translation function to translate from specifier as found in the
|
|
* device tree to id as given to the reset control ops
|
|
* @nr_resets: number of reset controls in this reset controller device
|
|
*/
|
|
struct reset_controller_dev {
|
|
const struct reset_control_ops *ops;
|
|
struct module *owner;
|
|
struct list_head list;
|
|
struct list_head reset_control_head;
|
|
struct device_node *of_node;
|
|
int of_reset_n_cells;
|
|
int (*of_xlate)(struct reset_controller_dev *rcdev,
|
|
const struct of_phandle_args *reset_spec);
|
|
unsigned int nr_resets;
|
|
};
|
|
|
|
int reset_controller_register(struct reset_controller_dev *rcdev);
|
|
void reset_controller_unregister(struct reset_controller_dev *rcdev);
|
|
|
|
struct device;
|
|
int devm_reset_controller_register(struct device *dev,
|
|
struct reset_controller_dev *rcdev);
|
|
|
|
void reset_controller_add_lookup(struct reset_controller_dev *rcdev,
|
|
struct reset_control_lookup *lookup,
|
|
unsigned int num_entries);
|
|
|
|
#endif
|