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1/* SPDX-License-Identifier: GPL-2.0+ */2/*3 * Main SSAM/SSH controller structure and functionality.4 *5 * Copyright (C) 2019-2022 Maximilian Luz <luzmaximilian@gmail.com>6 */7 8#ifndef _SURFACE_AGGREGATOR_CONTROLLER_H9#define _SURFACE_AGGREGATOR_CONTROLLER_H10 11#include <linux/kref.h>12#include <linux/list.h>13#include <linux/mutex.h>14#include <linux/rbtree.h>15#include <linux/rwsem.h>16#include <linux/serdev.h>17#include <linux/spinlock.h>18#include <linux/srcu.h>19#include <linux/types.h>20#include <linux/workqueue.h>21 22#include <linux/surface_aggregator/controller.h>23#include <linux/surface_aggregator/serial_hub.h>24 25#include "ssh_request_layer.h"26 27 28/* -- Safe counters. -------------------------------------------------------- */29 30/**31 * struct ssh_seq_counter - Safe counter for SSH sequence IDs.32 * @value: The current counter value.33 */34struct ssh_seq_counter {35 u8 value;36};37 38/**39 * struct ssh_rqid_counter - Safe counter for SSH request IDs.40 * @value: The current counter value.41 */42struct ssh_rqid_counter {43 u16 value;44};45 46 47/* -- Event/notification system. -------------------------------------------- */48 49/**50 * struct ssam_nf_head - Notifier head for SSAM events.51 * @srcu: The SRCU struct for synchronization.52 * @head: List-head for notifier blocks registered under this head.53 */54struct ssam_nf_head {55 struct srcu_struct srcu;56 struct list_head head;57};58 59/**60 * struct ssam_nf - Notifier callback- and activation-registry for SSAM events.61 * @lock: Lock guarding (de-)registration of notifier blocks. Note: This62 * lock does not need to be held for notifier calls, only63 * registration and deregistration.64 * @refcount: The root of the RB-tree used for reference-counting enabled65 * events/notifications.66 * @head: The list of notifier heads for event/notification callbacks.67 */68struct ssam_nf {69 struct mutex lock;70 struct rb_root refcount;71 struct ssam_nf_head head[SSH_NUM_EVENTS];72};73 74 75/* -- Event/async request completion system. -------------------------------- */76 77struct ssam_cplt;78 79/**80 * struct ssam_event_item - Struct for event queuing and completion.81 * @node: The node in the queue.82 * @rqid: The request ID of the event.83 * @ops: Instance specific functions.84 * @ops.free: Callback for freeing this event item.85 * @event: Actual event data.86 */87struct ssam_event_item {88 struct list_head node;89 u16 rqid;90 91 struct {92 void (*free)(struct ssam_event_item *event);93 } ops;94 95 struct ssam_event event; /* must be last */96};97 98/**99 * struct ssam_event_queue - Queue for completing received events.100 * @cplt: Reference to the completion system on which this queue is active.101 * @lock: The lock for any operation on the queue.102 * @head: The list-head of the queue.103 * @work: The &struct work_struct performing completion work for this queue.104 */105struct ssam_event_queue {106 struct ssam_cplt *cplt;107 108 spinlock_t lock;109 struct list_head head;110 struct work_struct work;111};112 113/**114 * struct ssam_event_target - Set of queues for a single SSH target ID.115 * @queue: The array of queues, one queue per event ID.116 */117struct ssam_event_target {118 struct ssam_event_queue queue[SSH_NUM_EVENTS];119};120 121/**122 * struct ssam_cplt - SSAM event/async request completion system.123 * @dev: The device with which this system is associated. Only used124 * for logging.125 * @wq: The &struct workqueue_struct on which all completion work126 * items are queued.127 * @event: Event completion management.128 * @event.target: Array of &struct ssam_event_target, one for each target.129 * @event.notif: Notifier callbacks and event activation reference counting.130 */131struct ssam_cplt {132 struct device *dev;133 struct workqueue_struct *wq;134 135 struct {136 struct ssam_event_target target[SSH_NUM_TARGETS];137 struct ssam_nf notif;138 } event;139};140 141 142/* -- Main SSAM device structures. ------------------------------------------ */143 144/**145 * enum ssam_controller_state - State values for &struct ssam_controller.146 * @SSAM_CONTROLLER_UNINITIALIZED:147 * The controller has not been initialized yet or has been deinitialized.148 * @SSAM_CONTROLLER_INITIALIZED:149 * The controller is initialized, but has not been started yet.150 * @SSAM_CONTROLLER_STARTED:151 * The controller has been started and is ready to use.152 * @SSAM_CONTROLLER_STOPPED:153 * The controller has been stopped.154 * @SSAM_CONTROLLER_SUSPENDED:155 * The controller has been suspended.156 */157enum ssam_controller_state {158 SSAM_CONTROLLER_UNINITIALIZED,159 SSAM_CONTROLLER_INITIALIZED,160 SSAM_CONTROLLER_STARTED,161 SSAM_CONTROLLER_STOPPED,162 SSAM_CONTROLLER_SUSPENDED,163};164 165/**166 * struct ssam_controller_caps - Controller device capabilities.167 * @ssh_power_profile: SSH power profile.168 * @ssh_buffer_size: SSH driver UART buffer size.169 * @screen_on_sleep_idle_timeout: SAM UART screen-on sleep idle timeout.170 * @screen_off_sleep_idle_timeout: SAM UART screen-off sleep idle timeout.171 * @d3_closes_handle: SAM closes UART handle in D3.172 *173 * Controller and SSH device capabilities found in ACPI.174 */175struct ssam_controller_caps {176 u32 ssh_power_profile;177 u32 ssh_buffer_size;178 u32 screen_on_sleep_idle_timeout;179 u32 screen_off_sleep_idle_timeout;180 u32 d3_closes_handle:1;181};182 183/**184 * struct ssam_controller - SSAM controller device.185 * @kref: Reference count of the controller.186 * @lock: Main lock for the controller, used to guard state changes.187 * @state: Controller state.188 * @rtl: Request transport layer for SSH I/O.189 * @cplt: Completion system for SSH/SSAM events and asynchronous requests.190 * @counter: Safe SSH message ID counters.191 * @counter.seq: Sequence ID counter.192 * @counter.rqid: Request ID counter.193 * @irq: Wakeup IRQ resources.194 * @irq.num: The wakeup IRQ number.195 * @irq.wakeup_enabled: Whether wakeup by IRQ is enabled during suspend.196 * @caps: The controller device capabilities.197 */198struct ssam_controller {199 struct kref kref;200 201 struct rw_semaphore lock;202 enum ssam_controller_state state;203 204 struct ssh_rtl rtl;205 struct ssam_cplt cplt;206 207 struct {208 struct ssh_seq_counter seq;209 struct ssh_rqid_counter rqid;210 } counter;211 212 struct {213 int num;214 bool wakeup_enabled;215 } irq;216 217 struct ssam_controller_caps caps;218};219 220#define to_ssam_controller(ptr, member) \221 container_of(ptr, struct ssam_controller, member)222 223#define ssam_dbg(ctrl, fmt, ...) rtl_dbg(&(ctrl)->rtl, fmt, ##__VA_ARGS__)224#define ssam_info(ctrl, fmt, ...) rtl_info(&(ctrl)->rtl, fmt, ##__VA_ARGS__)225#define ssam_warn(ctrl, fmt, ...) rtl_warn(&(ctrl)->rtl, fmt, ##__VA_ARGS__)226#define ssam_err(ctrl, fmt, ...) rtl_err(&(ctrl)->rtl, fmt, ##__VA_ARGS__)227 228/**229 * ssam_controller_receive_buf() - Provide input-data to the controller.230 * @ctrl: The controller.231 * @buf: The input buffer.232 * @n: The number of bytes in the input buffer.233 *234 * Provide input data to be evaluated by the controller, which has been235 * received via the lower-level transport.236 *237 * Return: Returns the number of bytes consumed, or, if the packet transport238 * layer of the controller has been shut down, %-ESHUTDOWN.239 */240static inline241ssize_t ssam_controller_receive_buf(struct ssam_controller *ctrl, const u8 *buf,242 size_t n)243{244 return ssh_ptl_rx_rcvbuf(&ctrl->rtl.ptl, buf, n);245}246 247/**248 * ssam_controller_write_wakeup() - Notify the controller that the underlying249 * device has space available for data to be written.250 * @ctrl: The controller.251 */252static inline void ssam_controller_write_wakeup(struct ssam_controller *ctrl)253{254 ssh_ptl_tx_wakeup_transfer(&ctrl->rtl.ptl);255}256 257int ssam_controller_init(struct ssam_controller *ctrl, struct serdev_device *s);258int ssam_controller_start(struct ssam_controller *ctrl);259void ssam_controller_shutdown(struct ssam_controller *ctrl);260void ssam_controller_destroy(struct ssam_controller *ctrl);261 262int ssam_notifier_disable_registered(struct ssam_controller *ctrl);263void ssam_notifier_restore_registered(struct ssam_controller *ctrl);264 265int ssam_irq_setup(struct ssam_controller *ctrl);266void ssam_irq_free(struct ssam_controller *ctrl);267int ssam_irq_arm_for_wakeup(struct ssam_controller *ctrl);268void ssam_irq_disarm_wakeup(struct ssam_controller *ctrl);269 270void ssam_controller_lock(struct ssam_controller *c);271void ssam_controller_unlock(struct ssam_controller *c);272 273int ssam_get_firmware_version(struct ssam_controller *ctrl, u32 *version);274int ssam_ctrl_notif_display_off(struct ssam_controller *ctrl);275int ssam_ctrl_notif_display_on(struct ssam_controller *ctrl);276int ssam_ctrl_notif_d0_exit(struct ssam_controller *ctrl);277int ssam_ctrl_notif_d0_entry(struct ssam_controller *ctrl);278 279int ssam_controller_suspend(struct ssam_controller *ctrl);280int ssam_controller_resume(struct ssam_controller *ctrl);281 282int ssam_event_item_cache_init(void);283void ssam_event_item_cache_destroy(void);284 285#endif /* _SURFACE_AGGREGATOR_CONTROLLER_H */286