From: Dmitry Torokhov =================================================================== ChangeSet@1.1800, 2004-06-18 03:11:02-05:00, dtor_core@ameritech.net Input: Add serio_raw driver that binds to serio ports and provides unobstructed access to the underlying serio port via a char device. The driver tries to register char device 10,1 (/dev/psaux) first and if it fails goes for dynamically allocated minor. To bind use sysfs interface: echo -n "serio_raw" > /sys/bus/serio/devices/serioX/driver Signed-off-by: Dmitry Torokhov Makefile | 1 =================================================================== Signed-off-by: Andrew Morton --- 25-akpm/drivers/input/serio/Kconfig | 16 + 25-akpm/drivers/input/serio/Makefile | 1 25-akpm/drivers/input/serio/serio_raw.c | 390 ++++++++++++++++++++++++++++++++ 3 files changed, 407 insertions(+) diff -puN drivers/input/serio/Kconfig~input-serio_raw-driver drivers/input/serio/Kconfig --- 25/drivers/input/serio/Kconfig~input-serio_raw-driver 2004-06-19 13:52:30.275943552 -0700 +++ 25-akpm/drivers/input/serio/Kconfig 2004-06-19 13:52:30.281942640 -0700 @@ -130,3 +130,19 @@ config SERIO_MACEPS2 To compile this driver as a module, choose M here: the module will be called maceps2. + +config SERIO_RAW + tristate "Raw access to serio ports" + depends on SERIO + help + Say Y here if you want to have raw access to serio ports, such as + AUX ports on i8042 keyboard controller. Each serio port that is + bound to this driver will be accessible via a char device with + major 10 and dynamically allocated minor. The driver will try + allocating minor 1 (that historically corresponds to /dev/psaux) + first. To bind this driver to a serio port use sysfs interface: + + echo -n "serio_raw" > /sys/bus/serio/devices/serioX/driver + + To compile this driver as a module, choose M here: the + module will be called serio_raw. diff -puN drivers/input/serio/Makefile~input-serio_raw-driver drivers/input/serio/Makefile --- 25/drivers/input/serio/Makefile~input-serio_raw-driver 2004-06-19 13:52:30.276943400 -0700 +++ 25-akpm/drivers/input/serio/Makefile 2004-06-19 13:52:30.281942640 -0700 @@ -17,3 +17,4 @@ obj-$(CONFIG_SERIO_98KBD) += 98kbd-io.o obj-$(CONFIG_SERIO_GSCPS2) += gscps2.o obj-$(CONFIG_SERIO_PCIPS2) += pcips2.o obj-$(CONFIG_SERIO_MACEPS2) += maceps2.o +obj-$(CONFIG_SERIO_RAW) += serio_raw.o diff -puN /dev/null drivers/input/serio/serio_raw.c --- /dev/null 2003-09-15 06:40:47.000000000 -0700 +++ 25-akpm/drivers/input/serio/serio_raw.c 2004-06-19 13:52:30.283942336 -0700 @@ -0,0 +1,390 @@ +/* + * Raw serio device providing access to a raw byte stream from underlying + * serio port. Closely emulates behavior of pre-2.6 /dev/psaux device + * + * Copyright (c) 2004 Dmitry Torokhov + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define DRIVER_DESC "Raw serio driver" + +MODULE_AUTHOR("Dmitry Torokhov "); +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_LICENSE("GPL"); + +#define SERIO_RAW_QUEUE_LEN 64 +struct serio_raw { + unsigned char queue[SERIO_RAW_QUEUE_LEN]; + unsigned int tail, head; + + char name[16]; + unsigned int refcnt; + struct serio *serio; + struct miscdevice dev; + wait_queue_head_t wait; + struct list_head list; + struct list_head node; +}; + +struct serio_raw_list { + struct fasync_struct *fasync; + struct serio_raw *serio_raw; + struct list_head node; +}; + +static DECLARE_MUTEX(serio_raw_sem); +static LIST_HEAD(serio_raw_list); +static unsigned int serio_raw_no; + +/********************************************************************* + * Interface with userspace (file operations) * + *********************************************************************/ + +static int serio_raw_fasync(int fd, struct file *file, int on) +{ + struct serio_raw_list *list = file->private_data; + int retval; + + retval = fasync_helper(fd, file, on, &list->fasync); + return retval < 0 ? retval : 0; +} + +static struct serio_raw *serio_raw_locate(int minor) +{ + struct serio_raw *serio_raw; + + list_for_each_entry(serio_raw, &serio_raw_list, node) { + if (serio_raw->dev.minor == minor) + return serio_raw; + } + + return NULL; +} + +static int serio_raw_open(struct inode *inode, struct file *file) +{ + struct serio_raw *serio_raw; + struct serio_raw_list *list; + int retval = 0; + + retval = down_interruptible(&serio_raw_sem); + if (retval) + return retval; + + if (!(serio_raw = serio_raw_locate(iminor(inode)))) { + retval = -ENODEV; + goto out; + } + + if (!serio_raw->serio) { + retval = -ENODEV; + goto out; + } + + if (!(list = kmalloc(sizeof(struct serio_raw_list), GFP_KERNEL))) { + retval = -ENOMEM; + goto out; + } + + memset(list, 0, sizeof(struct serio_raw_list)); + list->serio_raw = serio_raw; + file->private_data = list; + + serio_raw->refcnt++; + list_add_tail(&list->node, &serio_raw->list); + +out: + up(&serio_raw_sem); + return retval; +} + +static int serio_raw_cleanup(struct serio_raw *serio_raw) +{ + if (--serio_raw->refcnt == 0) { + misc_deregister(&serio_raw->dev); + list_del_init(&serio_raw->node); + kfree(serio_raw); + + return 1; + } + + return 0; +} + +static int serio_raw_release(struct inode *inode, struct file *file) +{ + struct serio_raw_list *list = file->private_data; + struct serio_raw *serio_raw = list->serio_raw; + + down(&serio_raw_sem); + + serio_raw_fasync(-1, file, 0); + serio_raw_cleanup(serio_raw); + + up(&serio_raw_sem); + return 0; +} + +static int serio_raw_fetch_byte(struct serio_raw *serio_raw, char *c) +{ + unsigned long flags; + int empty; + + spin_lock_irqsave(&serio_raw->serio->lock, flags); + + empty = serio_raw->head == serio_raw->tail; + if (!empty) { + *c = serio_raw->queue[serio_raw->tail]; + serio_raw->tail = (serio_raw->tail + 1) % SERIO_RAW_QUEUE_LEN; + } + + spin_unlock_irqrestore(&serio_raw->serio->lock, flags); + + return !empty; +} + +static ssize_t serio_raw_read(struct file *file, char *buffer, size_t count, loff_t *ppos) +{ + struct serio_raw_list *list = file->private_data; + struct serio_raw *serio_raw = list->serio_raw; + char c; + ssize_t retval = 0; + + if (!serio_raw->serio) + return -ENODEV; + + if (serio_raw->head == serio_raw->tail && (file->f_flags & O_NONBLOCK)) + return -EAGAIN; + + retval = wait_event_interruptible(list->serio_raw->wait, + serio_raw->head != serio_raw->tail || !serio_raw->serio); + if (retval) + return retval; + + if (!serio_raw->serio) + return -ENODEV; + + while (retval < count && serio_raw_fetch_byte(serio_raw, &c)) { + if (put_user(c, buffer++)) + return -EFAULT; + retval++; + } + + return retval; +} + +static ssize_t serio_raw_write(struct file *file, const char *buffer, size_t count, loff_t *ppos) +{ + struct serio_raw_list *list = file->private_data; + ssize_t written = 0; + int retval; + unsigned char c; + + retval = down_interruptible(&serio_raw_sem); + if (retval) + return retval; + + if (!list->serio_raw->serio) { + retval = -ENODEV; + goto out; + } + + if (count > 32) + count = 32; + + while (count--) { + if (get_user(c, buffer++)) { + retval = -EFAULT; + goto out; + } + if (serio_write(list->serio_raw->serio, c)) { + retval = -EIO; + goto out; + } + written++; + }; + +out: + up(&serio_raw_sem); + return written; +} + +static unsigned int serio_raw_poll(struct file *file, poll_table *wait) +{ + struct serio_raw_list *list = file->private_data; + + poll_wait(file, &list->serio_raw->wait, wait); + + if (list->serio_raw->head != list->serio_raw->tail) + return POLLIN | POLLRDNORM; + + return 0; +} + +struct file_operations serio_raw_fops = { + .owner = THIS_MODULE, + .open = serio_raw_open, + .release = serio_raw_release, + .read = serio_raw_read, + .write = serio_raw_write, + .poll = serio_raw_poll, + .fasync = serio_raw_fasync, +}; + + +/********************************************************************* + * Interface with serio port * + *********************************************************************/ + +static irqreturn_t serio_raw_interrupt(struct serio *serio, unsigned char data, + unsigned int dfl, struct pt_regs *regs) +{ + struct serio_raw *serio_raw = serio->private; + struct serio_raw_list *list; + unsigned int head = serio_raw->head; + + /* we are holding serio->lock here so we are prootected */ + serio_raw->queue[head] = data; + head = (head + 1) % SERIO_RAW_QUEUE_LEN; + if (likely(head != serio_raw->tail)) { + serio_raw->head = head; + list_for_each_entry(list, &serio_raw->list, node) + kill_fasync(&list->fasync, SIGIO, POLL_IN); + wake_up_interruptible(&serio_raw->wait); + } + + return IRQ_HANDLED; +} + +static void serio_raw_connect(struct serio *serio, struct serio_driver *drv) +{ + struct serio_raw *serio_raw; + int err; + + if ((serio->type & SERIO_TYPE) != SERIO_8042) + return; + + if (!(serio_raw = kmalloc(sizeof(struct serio_raw), GFP_KERNEL))) { + printk(KERN_ERR "serio_raw.c: can't allocate memory for a device\n"); + return; + } + + down(&serio_raw_sem); + + memset(serio_raw, 0, sizeof(struct serio_raw)); + snprintf(serio_raw->name, sizeof(serio_raw->name), "serio_raw%d", serio_raw_no++); + serio_raw->refcnt = 1; + serio_raw->serio = serio; + INIT_LIST_HEAD(&serio_raw->list); + init_waitqueue_head(&serio_raw->wait); + + serio->private = serio_raw; + if (serio_open(serio, drv)) + goto out_free; + + list_add_tail(&serio_raw->node, &serio_raw_list); + + serio_raw->dev.minor = PSMOUSE_MINOR; + serio_raw->dev.name = serio_raw->name; + serio_raw->dev.fops = &serio_raw_fops; + + err = misc_register(&serio_raw->dev); + if (err) { + serio_raw->dev.minor = MISC_DYNAMIC_MINOR; + err = misc_register(&serio_raw->dev); + } + + if (err) { + printk(KERN_INFO "serio_raw: failed to register raw access device for %s\n", + serio->phys); + goto out_close; + } + + printk(KERN_INFO "serio_raw: raw access enabled on %s (%s, minor %d)\n", + serio->phys, serio_raw->name, serio_raw->dev.minor); + goto out; + +out_close: + serio_close(serio); + list_del_init(&serio_raw->node); +out_free: + serio->private = NULL; + kfree(serio_raw); +out: + up(&serio_raw_sem); +} + +static int serio_raw_reconnect(struct serio *serio) +{ + struct serio_raw *serio_raw = serio->private; + struct serio_driver *drv = serio->drv; + + if (!drv || !serio_raw) { + printk(KERN_DEBUG "serio_raw: reconnect request, but serio is disconnected, ignoring...\n"); + return -1; + } + + /* + * Nothing needs to be done here, we just need this method to + * keep the same device. + */ + return 0; +} + +static void serio_raw_disconnect(struct serio *serio) +{ + struct serio_raw *serio_raw; + + down(&serio_raw_sem); + + serio_raw = serio->private; + + serio_close(serio); + serio->private = NULL; + + serio_raw->serio = NULL; + if (!serio_raw_cleanup(serio_raw)) + wake_up_interruptible(&serio_raw->wait); + + up(&serio_raw_sem); +} + +static struct serio_driver serio_raw_drv = { + .driver = { + .name = "serio_raw", + }, + .description = DRIVER_DESC, + .interrupt = serio_raw_interrupt, + .connect = serio_raw_connect, + .reconnect = serio_raw_reconnect, + .disconnect = serio_raw_disconnect, + .manual_bind = 1, +}; + +int __init serio_raw_init(void) +{ + serio_register_driver(&serio_raw_drv); + return 0; +} + +void __exit serio_raw_exit(void) +{ + serio_unregister_driver(&serio_raw_drv); +} + +module_init(serio_raw_init); +module_exit(serio_raw_exit); _