6  * This program is free software; you can redistribute it and/or modify it
8  * the Free Software Foundation; either version 2 of the License, or (at
39 	bool running;  member
51  * userio_device_write - Write data from serio to a userio device in userspace
57 	struct userio_device *userio = id->port_data;  in userio_device_write()
60 	spin_lock_irqsave(&userio->buf_lock, flags);  in userio_device_write()
62 	userio->buf[userio->head] = val;  in userio_device_write()
63 	userio->head = (userio->head + 1) % USERIO_BUFSIZE;  in userio_device_write()
65 	if (userio->head == userio->tail)  in userio_device_write()
69 	spin_unlock_irqrestore(&userio->buf_lock, flags);  in userio_device_write()
71 	wake_up_interruptible(&userio->waitq);  in userio_device_write()
82 		return -ENOMEM;  in userio_char_open()
84 	mutex_init(&userio->mutex);  in userio_char_open()
85 	spin_lock_init(&userio->buf_lock);  in userio_char_open()
86 	init_waitqueue_head(&userio->waitq);  in userio_char_open()
88 	userio->serio = kzalloc(sizeof(*userio->serio), GFP_KERNEL);  in userio_char_open()
89 	if (!userio->serio) {  in userio_char_open()
91 		return -ENOMEM;  in userio_char_open()
94 	userio->serio->write = userio_device_write;  in userio_char_open()
95 	userio->serio->port_data = userio;  in userio_char_open()
97 	file->private_data = userio;  in userio_char_open()
104 	struct userio_device *userio = file->private_data;  in userio_char_release()
106 	if (userio->running) {  in userio_char_release()
108 		 * Don't free the serio port here, serio_unregister_port()  in userio_char_release()
111 		serio_unregister_port(userio->serio);  in userio_char_release()
113 		kfree(userio->serio);  in userio_char_release()
124 	struct userio_device *userio = file->private_data;  in userio_char_read()
134 	 * until we have data (unless the file descriptor is non-blocking  in userio_char_read()
138 		spin_lock_irqsave(&userio->buf_lock, flags);  in userio_char_read()
140 		nonwrap_len = CIRC_CNT_TO_END(userio->head,  in userio_char_read()
141 					      userio->tail,  in userio_char_read()
145 			memcpy(buf, &userio->buf[userio->tail], copylen);  in userio_char_read()
146 			userio->tail = (userio->tail + copylen) %  in userio_char_read()
150 		spin_unlock_irqrestore(&userio->buf_lock, flags);  in userio_char_read()
156 		if (file->f_flags & O_NONBLOCK)  in userio_char_read()
157 			return -EAGAIN;  in userio_char_read()
160 		 * count == 0 is special - no IO is done but we check  in userio_char_read()
166 		error = wait_event_interruptible(userio->waitq,  in userio_char_read()
167 						 userio->head != userio->tail);  in userio_char_read()
174 			return -EFAULT;  in userio_char_read()
182 	struct userio_device *userio = file->private_data;  in userio_char_write()
188 		return -EINVAL;  in userio_char_write()
192 		return -EFAULT;  in userio_char_write()
194 	error = mutex_lock_interruptible(&userio->mutex);  in userio_char_write()
200 		if (!userio->serio->id.type) {  in userio_char_write()
204 			error = -EINVAL;  in userio_char_write()
208 		if (userio->running) {  in userio_char_write()
210 				 "Begin command sent, but we're already running\n");  in userio_char_write()
211 			error = -EBUSY;  in userio_char_write()
215 		userio->running = true;  in userio_char_write()
216 		serio_register_port(userio->serio);  in userio_char_write()
220 		if (userio->running) {  in userio_char_write()
222 				 "Can't change port type on an already running userio instance\n");  in userio_char_write()
223 			error = -EBUSY;  in userio_char_write()
227 		userio->serio->id.type = cmd.data;  in userio_char_write()
231 		if (!userio->running) {  in userio_char_write()
234 			error = -ENODEV;  in userio_char_write()
238 		serio_interrupt(userio->serio, cmd.data, 0);  in userio_char_write()
242 		error = -EOPNOTSUPP;  in userio_char_write()
247 	mutex_unlock(&userio->mutex);  in userio_char_write()
253 	struct userio_device *userio = file->private_data;  in userio_char_poll()
255 	poll_wait(file, &userio->waitq, wait);  in userio_char_poll()
257 	if (userio->head != userio->tail)  in userio_char_poll()