/* SPDX-License-Identifier: GPL-2.0+ */
/*
* Main SSAM/SSH controller structure and functionality.
*
* Copyright (C) 2019-2022 Maximilian Luz <[email protected]>
*/
#ifndef _SURFACE_AGGREGATOR_CONTROLLER_H
#define _SURFACE_AGGREGATOR_CONTROLLER_H
#include <linux/kref.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/rbtree.h>
#include <linux/rwsem.h>
#include <linux/serdev.h>
#include <linux/spinlock.h>
#include <linux/srcu.h>
#include <linux/types.h>
#include <linux/workqueue.h>
#include <linux/surface_aggregator/controller.h>
#include <linux/surface_aggregator/serial_hub.h>
#include "ssh_request_layer.h"
/* -- Safe counters. -------------------------------------------------------- */
/**
* struct ssh_seq_counter - Safe counter for SSH sequence IDs.
* @value: The current counter value.
*/
struct ssh_seq_counter {
u8 value;
};
/**
* struct ssh_rqid_counter - Safe counter for SSH request IDs.
* @value: The current counter value.
*/
struct ssh_rqid_counter {
u16 value;
};
/* -- Event/notification system. -------------------------------------------- */
/**
* struct ssam_nf_head - Notifier head for SSAM events.
* @srcu: The SRCU struct for synchronization.
* @head: List-head for notifier blocks registered under this head.
*/
struct ssam_nf_head {
struct srcu_struct srcu;
struct list_head head;
};
/**
* struct ssam_nf - Notifier callback- and activation-registry for SSAM events.
* @lock: Lock guarding (de-)registration of notifier blocks. Note: This
* lock does not need to be held for notifier calls, only
* registration and deregistration.
* @refcount: The root of the RB-tree used for reference-counting enabled
* events/notifications.
* @head: The list of notifier heads for event/notification callbacks.
*/
struct ssam_nf {
struct mutex lock;
struct rb_root refcount;
struct ssam_nf_head head[SSH_NUM_EVENTS];
};
/* -- Event/async request completion system. -------------------------------- */
struct ssam_cplt;
/**
* struct ssam_event_item - Struct for event queuing and completion.
* @node: The node in the queue.
* @rqid: The request ID of the event.
* @ops: Instance specific functions.
* @ops.free: Callback for freeing this event item.
* @event: Actual event data.
*/
struct ssam_event_item {
struct list_head node;
u16 rqid;
struct {
void (*free)(struct ssam_event_item *event);
} ops;
struct ssam_event event; /* must be last */
};
/**
* struct ssam_event_queue - Queue for completing received events.
* @cplt: Reference to the completion system on which this queue is active.
* @lock: The lock for any operation on the queue.
* @head: The list-head of the queue.
* @work: The &struct work_struct performing completion work for this queue.
*/
struct ssam_event_queue {
struct ssam_cplt *cplt;
spinlock_t lock;
struct list_head head;
struct work_struct work;
};
/**
* struct ssam_event_target - Set of queues for a single SSH target ID.
* @queue: The array of queues, one queue per event ID.
*/
struct ssam_event_target {
struct ssam_event_queue queue[SSH_NUM_EVENTS];
};
/**
* struct ssam_cplt - SSAM event/async request completion system.
* @dev: The device with which this system is associated. Only used
* for logging.
* @wq: The &struct workqueue_struct on which all completion work
* items are queued.
* @event: Event completion management.
* @event.target: Array of &struct ssam_event_target, one for each target.
* @event.notif: Notifier callbacks and event activation reference counting.
*/
struct ssam_cplt {
struct device *dev;
struct workqueue_struct *wq;
struct {
struct ssam_event_target target[SSH_NUM_TARGETS];
struct ssam_nf notif;
} event;
};
/* -- Main SSAM device structures. ------------------------------------------ */
/**
* enum ssam_controller_state - State values for &struct ssam_controller.
* @SSAM_CONTROLLER_UNINITIALIZED:
* The controller has not been initialized yet or has been deinitialized.
* @SSAM_CONTROLLER_INITIALIZED:
* The controller is initialized, but has not been started yet.
* @SSAM_CONTROLLER_STARTED:
* The controller has been started and is ready to use.
* @SSAM_CONTROLLER_STOPPED:
* The controller has been stopped.
* @SSAM_CONTROLLER_SUSPENDED:
* The controller has been suspended.
*/
enum ssam_controller_state {
SSAM_CONTROLLER_UNINITIALIZED,
SSAM_CONTROLLER_INITIALIZED,
SSAM_CONTROLLER_STARTED,
SSAM_CONTROLLER_STOPPED,
SSAM_CONTROLLER_SUSPENDED,
};
/**
* struct ssam_controller_caps - Controller device capabilities.
* @ssh_power_profile: SSH power profile.
* @ssh_buffer_size: SSH driver UART buffer size.
* @screen_on_sleep_idle_timeout: SAM UART screen-on sleep idle timeout.
* @screen_off_sleep_idle_timeout: SAM UART screen-off sleep idle timeout.
* @d3_closes_handle: SAM closes UART handle in D3.
*
* Controller and SSH device capabilities found in ACPI.
*/
struct ssam_controller_caps {
u32 ssh_power_profile;
u32 ssh_buffer_size;
u32 screen_on_sleep_idle_timeout;
u32 screen_off_sleep_idle_timeout;
u32 d3_closes_handle:1;
};
/**
* struct ssam_controller - SSAM controller device.
* @kref: Reference count of the controller.
* @lock: Main lock for the controller, used to guard state changes.
* @state: Controller state.
* @rtl: Request transport layer for SSH I/O.
* @cplt: Completion system for SSH/SSAM events and asynchronous requests.
* @counter: Safe SSH message ID counters.
* @counter.seq: Sequence ID counter.
* @counter.rqid: Request ID counter.
* @irq: Wakeup IRQ resources.
* @irq.num: The wakeup IRQ number.
* @irq.wakeup_enabled: Whether wakeup by IRQ is enabled during suspend.
* @caps: The controller device capabilities.
*/
struct ssam_controller {
struct kref kref;
struct rw_semaphore lock;
enum ssam_controller_state state;
struct ssh_rtl rtl;
struct ssam_cplt cplt;
struct {
struct ssh_seq_counter seq;
struct ssh_rqid_counter rqid;
} counter;
struct {
int num;
bool wakeup_enabled;
} irq;
struct ssam_controller_caps caps;
};
#define to_ssam_controller(ptr, member) \
container_of(ptr, struct ssam_controller, member)
#define ssam_dbg(ctrl, fmt, ...) rtl_dbg(&(ctrl)->rtl, fmt, ##__VA_ARGS__)
#define ssam_info(ctrl, fmt, ...) rtl_info(&(ctrl)->rtl, fmt, ##__VA_ARGS__)
#define ssam_warn(ctrl, fmt, ...) rtl_warn(&(ctrl)->rtl, fmt, ##__VA_ARGS__)
#define ssam_err(ctrl, fmt, ...) rtl_err(&(ctrl)->rtl, fmt, ##__VA_ARGS__)
/**
* ssam_controller_receive_buf() - Provide input-data to the controller.
* @ctrl: The controller.
* @buf: The input buffer.
* @n: The number of bytes in the input buffer.
*
* Provide input data to be evaluated by the controller, which has been
* received via the lower-level transport.
*
* Return: Returns the number of bytes consumed, or, if the packet transport
* layer of the controller has been shut down, %-ESHUTDOWN.
*/
static inline
ssize_t ssam_controller_receive_buf(struct ssam_controller *ctrl, const u8 *buf,
size_t n)
{
return ssh_ptl_rx_rcvbuf(&ctrl->rtl.ptl, buf, n);
}
/**
* ssam_controller_write_wakeup() - Notify the controller that the underlying
* device has space available for data to be written.
* @ctrl: The controller.
*/
static inline void ssam_controller_write_wakeup(struct ssam_controller *ctrl)
{
ssh_ptl_tx_wakeup_transfer(&ctrl->rtl.ptl);
}
int ssam_controller_init(struct ssam_controller *ctrl, struct serdev_device *s);
int ssam_controller_start(struct ssam_controller *ctrl);
void ssam_controller_shutdown(struct ssam_controller *ctrl);
void ssam_controller_destroy(struct ssam_controller *ctrl);
int ssam_notifier_disable_registered(struct ssam_controller *ctrl);
void ssam_notifier_restore_registered(struct ssam_controller *ctrl);
int ssam_irq_setup(struct ssam_controller *ctrl);
void ssam_irq_free(struct ssam_controller *ctrl);
int ssam_irq_arm_for_wakeup(struct ssam_controller *ctrl);
void ssam_irq_disarm_wakeup(struct ssam_controller *ctrl);
void ssam_controller_lock(struct ssam_controller *c);
void ssam_controller_unlock(struct ssam_controller *c);
int ssam_get_firmware_version(struct ssam_controller *ctrl, u32 *version);
int ssam_ctrl_notif_display_off(struct ssam_controller *ctrl);
int ssam_ctrl_notif_display_on(struct ssam_controller *ctrl);
int ssam_ctrl_notif_d0_exit(struct ssam_controller *ctrl);
int ssam_ctrl_notif_d0_entry(struct ssam_controller *ctrl);
int ssam_controller_suspend(struct ssam_controller *ctrl);
int ssam_controller_resume(struct ssam_controller *ctrl);
int ssam_event_item_cache_init(void);
void ssam_event_item_cache_destroy(void);
#endif /* _SURFACE_AGGREGATOR_CONTROLLER_H */
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