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Diffstat (limited to 'drivers/platform/surface/aggregator/controller.h')
| -rw-r--r-- | drivers/platform/surface/aggregator/controller.h | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/drivers/platform/surface/aggregator/controller.h b/drivers/platform/surface/aggregator/controller.h new file mode 100644 index 000000000000..8297d34e7489 --- /dev/null +++ b/drivers/platform/surface/aggregator/controller.h @@ -0,0 +1,285 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Main SSAM/SSH controller structure and functionality. + * + * Copyright (C) 2019-2020 Maximilian Luz <luzmaximilian@gmail.com> + */ + +#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 +int ssam_controller_receive_buf(struct ssam_controller *ctrl, + const unsigned char *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 */ |