include/linux/serio.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (C) 1999-2002 Vojtech Pavlik
   4  */
   5 #ifndef _SERIO_H
   6 #define _SERIO_H
   7
   8
   9 #include <linux/cleanup.h>
  10 #include <linux/types.h>
  11 #include <linux/interrupt.h>
  12 #include <linux/list.h>
  13 #include <linux/spinlock.h>
  14 #include <linux/mutex.h>
  15 #include <linux/device.h>
  16 #include <linux/mod_devicetable.h>
  17 #include <uapi/linux/serio.h>
  18
  19 extern const struct bus_type serio_bus;
  20
  21 struct serio {
  22         void *port_data;
  23
  24         char name[32];
  25         char phys[32];
  26         char firmware_id[128];
  27
  28         bool manual_bind;
  29
  30         struct serio_device_id id;
  31
  32         /* Protects critical sections from port's interrupt handler */
  33         spinlock_t lock;
  34
  35         int (*write)(struct serio *, unsigned char);
  36         int (*open)(struct serio *);
  37         void (*close)(struct serio *);
  38         int (*start)(struct serio *);
  39         void (*stop)(struct serio *);
  40
  41         struct serio *parent;
  42         /* Entry in parent->children list */
  43         struct list_head child_node;
  44         struct list_head children;
  45         /* Level of nesting in serio hierarchy */
  46         unsigned int depth;
  47
  48         /*
  49          * serio->drv is accessed from interrupt handlers; when modifying
  50          * caller should acquire serio->drv_mutex and serio->lock.
  51          */
  52         struct serio_driver *drv;
  53         /* Protects serio->drv so attributes can pin current driver */
  54         struct mutex drv_mutex;
  55
  56         struct device dev;
  57
  58         struct list_head node;
  59
  60         /*
  61          * For use by PS/2 layer when several ports share hardware and
  62          * may get indigestion when exposed to concurrent access (i8042).
  63          */
  64         struct mutex *ps2_cmd_mutex;
  65 };
  66 #define to_serio_port(d)        container_of(d, struct serio, dev)
  67
  68 struct serio_driver {
  69         const char *description;
  70
  71         const struct serio_device_id *id_table;
  72         bool manual_bind;
  73
  74         void (*write_wakeup)(struct serio *);
  75         irqreturn_t (*interrupt)(struct serio *, unsigned char, unsigned int);
  76         int  (*connect)(struct serio *, struct serio_driver *drv);
  77         int  (*reconnect)(struct serio *);
  78         int  (*fast_reconnect)(struct serio *);
  79         void (*disconnect)(struct serio *);
  80         void (*cleanup)(struct serio *);
  81
  82         struct device_driver driver;
  83 };
  84 #define to_serio_driver(d)      container_of_const(d, struct serio_driver, driver)
  85
  86 int serio_open(struct serio *serio, struct serio_driver *drv);
  87 void serio_close(struct serio *serio);
  88 void serio_rescan(struct serio *serio);
  89 void serio_reconnect(struct serio *serio);
  90 irqreturn_t serio_interrupt(struct serio *serio, unsigned char data, unsigned int flags);
  91
  92 void __serio_register_port(struct serio *serio, struct module *owner);
  93
  94 /* use a define to avoid include chaining to get THIS_MODULE */
  95 #define serio_register_port(serio) \
  96         __serio_register_port(serio, THIS_MODULE)
  97
  98 void serio_unregister_port(struct serio *serio);
  99 void serio_unregister_child_port(struct serio *serio);
 100
 101 int __must_check __serio_register_driver(struct serio_driver *drv,
 102                                 struct module *owner, const char *mod_name);
 103
 104 /* use a define to avoid include chaining to get THIS_MODULE & friends */
 105 #define serio_register_driver(drv) \
 106         __serio_register_driver(drv, THIS_MODULE, KBUILD_MODNAME)
 107
 108 void serio_unregister_driver(struct serio_driver *drv);
 109
 110 /**
 111  * module_serio_driver() - Helper macro for registering a serio driver
 112  * @__serio_driver: serio_driver struct
 113  *
 114  * Helper macro for serio drivers which do not do anything special in
 115  * module init/exit. This eliminates a lot of boilerplate. Each module
 116  * may only use this macro once, and calling it replaces module_init()
 117  * and module_exit().
 118  */
 119 #define module_serio_driver(__serio_driver) \
 120         module_driver(__serio_driver, serio_register_driver, \
 121                        serio_unregister_driver)
 122
 123 static inline int serio_write(struct serio *serio, unsigned char data)
 124 {
 125         if (serio->write)
 126                 return serio->write(serio, data);
 127         else
 128                 return -1;
 129 }
 130
 131 static inline void serio_drv_write_wakeup(struct serio *serio)
 132 {
 133         if (serio->drv && serio->drv->write_wakeup)
 134                 serio->drv->write_wakeup(serio);
 135 }
 136
 137 /*
 138  * Use the following functions to manipulate serio's per-port
 139  * driver-specific data.
 140  */
 141 static inline void *serio_get_drvdata(struct serio *serio)
 142 {
 143         return dev_get_drvdata(&serio->dev);
 144 }
 145
 146 static inline void serio_set_drvdata(struct serio *serio, void *data)
 147 {
 148         dev_set_drvdata(&serio->dev, data);
 149 }
 150
 151 /*
 152  * Use the following functions to protect critical sections in
 153  * driver code from port's interrupt handler
 154  */
 155 static inline void serio_pause_rx(struct serio *serio)
 156 {
 157         spin_lock_irq(&serio->lock);
 158 }
 159
 160 static inline void serio_continue_rx(struct serio *serio)
 161 {
 162         spin_unlock_irq(&serio->lock);
 163 }
 164
 165 DEFINE_GUARD(serio_pause_rx, struct serio *, serio_pause_rx(_T), serio_continue_rx(_T))
 166
 167 #endif