/* -*- c -*- --------------------------------------------------------- * * * linux/drivers/char/mk712.c * * Copyright 1999-2002 Transmeta Corporation * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * This driver supports the MK712 touch screen. * based on busmouse.c, pc_keyb.c, and other mouse drivers * * 1999-12-18: original version, Daniel Quinlan * 1999-12-19: added anti-jitter code, report pen-up events, fixed mk712_poll * to use queue_empty, Nathan Laredo * 1999-12-20: improved random point rejection, Nathan Laredo * 2000-01-05: checked in new anti-jitter code, changed mouse protocol, fixed * queue code, added module options, other fixes, Daniel Quinlan * 2002-03-15: Clean up for kernel merge * Fixed multi open race, fixed memory checks, fixed resource * allocation, fixed close/powerdown bug, switched to new init * * ------------------------------------------------------------------------- */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define DEBUG(x) x #define SQUARE(x) ((x)*(x)) #define MK712_DEFAULT_IO 0x260 /* demo board: 0x200, 0x208, 0x300 */ #define MK712_DEFAULT_IRQ 10 /* demo board: 10, 12, 14 or 15 */ /* eight 8-bit registers */ #define MK712_STATUS_LOW 0 /* READ */ #define MK712_STATUS_HIGH 1 /* READ */ #define MK712_X_LOW 2 /* READ */ #define MK712_X_HIGH 3 /* READ */ #define MK712_Y_LOW 4 /* READ */ #define MK712_Y_HIGH 5 /* READ */ #define MK712_CONTROL 6 /* R/W */ #define MK712_RATE 7 /* R/W */ /* status */ #define MK712_STATUS_TOUCH 0x10 #define MK712_CONVERSION_COMPLETE 0x80 #define MK712_ENABLE_INT 0x01 /* enable interrupts */ #define MK712_INT_ON_CONVERSION_COMPLETE 0x02 /* if bit 0 = 1 */ #define MK712_INT_ON_CHANGE_IN_TOUCH_STATUS_A 0x04 /* if bit 0 = 1 */ #define MK712_INT_ON_CHANGE_IN_TOUCH_STATUS_B 0x08 /* if bit 0 = 1 */ #define MK712_ENABLE_PERIODIC_CONVERSIONS 0x10 #define MK712_READ_ONE_POINT 0x20 #define MK712_POWERDOWN_A 0x40 #define MK712_POWERDOWN_B 0x80 #define MK712_BUF_SIZE 256 /* a page */ struct mk712_packet { unsigned int header; unsigned int x; unsigned int y; unsigned int reserved; }; struct mk712_queue { unsigned long head; unsigned long tail; wait_queue_head_t proc_list; struct fasync_struct *fasync; struct mk712_packet buf[256]; }; #ifdef MODULE static int io = 0; static int irq = 0; #endif static int mk712_io = MK712_DEFAULT_IO; static int mk712_irq = MK712_DEFAULT_IRQ; static int mk712_users = 0; static spinlock_t mk712_lock = SPIN_LOCK_UNLOCKED; static struct mk712_queue *queue; /* mouse data buffer */ static struct mk712_packet get_from_queue(void) { struct mk712_packet result; unsigned long flags; spin_lock_irqsave(&mk712_lock, flags); result = queue->buf[queue->tail]; queue->tail = (queue->tail + 1) & (MK712_BUF_SIZE-1); spin_unlock_irqrestore(&mk712_lock, flags); return result; } static inline int queue_empty(void) { return queue->head == queue->tail; } static int mk712_fasync(int fd, struct file *filp, int on) { int retval; retval = fasync_helper(fd, filp, on, &queue->fasync); if (retval < 0) return retval; return 0; } static void mk712_output_packet(struct mk712_packet data) { int head = queue->head; queue->buf[head] = data; head = (head + 1) & (MK712_BUF_SIZE-1); if (head != queue->tail) { queue->head = head; kill_fasync(&queue->fasync, SIGIO, POLL_IN); wake_up_interruptible(&queue->proc_list); } } static int points = 0; /* number of stored points */ static int output_point = 0; /* did I output a point since last release? */ static void mk712_output_point(int x, int y) { struct mk712_packet t; t.header = 0; t.x = x; t.y = y; t.reserved = 0; mk712_output_packet(t); output_point = 1; } static void mk712_store_point(int x_new, int y_new) { static int x[3], y[3]; int x_out, y_out; x[points] = x_new; y[points] = y_new; if (points == 1 && abs(x[0] - x[1]) < 88 && abs(y[0] - y[1]) < 88) { x_out = (x[0] + x[1]) >> 1; y_out = (y[0] + y[1]) >> 1; mk712_output_point(x_out, y_out); } if (points == 2) { if ((abs(x[1] - x[2]) < 88 && abs(y[1] - y[2]) < 88) && (abs(x[0] - x[1]) < 88 && abs(y[0] - y[1]) < 88)) { x_out = (x[0] + x[1] + x[2]) / 3; y_out = (y[0] + y[1] + y[2]) / 3; mk712_output_point(x_out, y_out); } else if (abs(x[1] - x[2]) < 88 && abs(y[1] - y[2]) < 88) { x_out = (x[1] + x[2]) >> 1; y_out = (y[1] + y[2]) >> 1; mk712_output_point(x_out, y_out); } else { int x_avg, y_avg, d0, d1, d2; x_avg = (x[0] + x[1] + x[2]) / 3; y_avg = (y[0] + y[1] + y[2]) / 3; d0 = SQUARE(x[0] - x_avg) + SQUARE(y[0] - y_avg); d1 = SQUARE(x[1] - x_avg) + SQUARE(y[1] - y_avg); d2 = SQUARE(x[2] - x_avg) + SQUARE(y[2] - y_avg); if (d2 > d1 && d2 > d0) { x_out = (x[0] + x[1]) >> 1; y_out = (y[0] + y[1]) >> 1; } if (d1 > d0 && d1 > d2) { x_out = (x[0] + x[2]) >> 1; y_out = (y[0] + y[2]) >> 1; } else { x_out = (x[1] + x[2]) >> 1; y_out = (y[1] + y[2]) >> 1; } mk712_output_point(x_out, y_out); x[0] = x[1]; x[1] = x[2]; y[0] = y[1]; y[1] = y[2]; } } else { points++; } } static void mk712_release_event(void) { struct mk712_packet t; if (!output_point) { points = 0; return; } output_point = 0; t.header = 1; t.x = t.y = t.reserved = 0; mk712_output_packet(t); points = 0; } #define MK712_FILTER static void mk712_interrupt(int irq, void *dev_id, struct pt_regs *regs) { unsigned short x; unsigned short y; unsigned char status; unsigned long flags; #ifdef MK712_FILTER static int drop_next = 1; #endif spin_lock_irqsave(&mk712_lock, flags); status = inb(mk712_io + MK712_STATUS_LOW); if (!(status & MK712_CONVERSION_COMPLETE)) { #ifdef MK712_FILTER drop_next = 1; #endif return; } if (!(status & MK712_STATUS_TOUCH)) /* release event */ { #ifdef MK712_FILTER drop_next = 1; #endif mk712_release_event(); spin_unlock_irqrestore(&mk712_lock, flags); wake_up_interruptible(&queue->proc_list); return; } x = inw(mk712_io + MK712_X_LOW) & 0x0fff; y = inw(mk712_io + MK712_Y_LOW) & 0x0fff; #ifdef MK712_FILTER if (drop_next) { drop_next = 0; spin_unlock_irqrestore(&mk712_lock, flags); wake_up_interruptible(&queue->proc_list); return; } #endif x = inw(mk712_io + MK712_X_LOW) & 0x0fff; y = inw(mk712_io + MK712_Y_LOW) & 0x0fff; mk712_store_point(x, y); spin_unlock_irqrestore(&mk712_lock, flags); wake_up_interruptible(&queue->proc_list); } static int mk712_open(struct inode *inode, struct file *file) { unsigned char control; unsigned long flags; control = 0; spin_lock_irqsave(&mk712_lock, flags); if(!mk712_users++) { outb(0, mk712_io + MK712_CONTROL); control |= (MK712_ENABLE_INT | MK712_INT_ON_CONVERSION_COMPLETE | MK712_INT_ON_CHANGE_IN_TOUCH_STATUS_B | MK712_ENABLE_PERIODIC_CONVERSIONS | MK712_POWERDOWN_A); outb(control, mk712_io + MK712_CONTROL); outb(10, mk712_io + MK712_RATE); /* default count = 10 */ queue->head = queue->tail = 0; /* Flush input queue */ } spin_unlock_irqrestore(&mk712_lock, flags); return 0; } static int mk712_close(struct inode * inode, struct file * file) { /* power down controller */ unsigned long flags; spin_lock_irqsave(&mk712_lock, flags); if(--mk712_users==0) outb(0, mk712_io + MK712_CONTROL); spin_unlock_irqrestore(&mk712_lock, flags); return 0; } static unsigned int mk712_poll(struct file *file, poll_table *wait) { poll_wait(file, &queue->proc_list, wait); if(!queue_empty()) return POLLIN | POLLRDNORM; return 0; } static int mk712_ioctl(struct inode *inode, struct file * file, unsigned int cmd, unsigned long arg) { if (!inode) BUG(); return -ENOTTY; } static ssize_t mk712_read(struct file *file, char *buffer, size_t count, loff_t *pos) { DECLARE_WAITQUEUE(wait, current); ssize_t bytes_read = 0; struct mk712_packet p; /* wait for an event */ if (queue_empty()) { if (file->f_flags & O_NONBLOCK) return -EAGAIN; add_wait_queue(&queue->proc_list, &wait); repeat: set_current_state(TASK_INTERRUPTIBLE); if (queue_empty() && !signal_pending(current)) { schedule(); goto repeat; } current->state = TASK_RUNNING; remove_wait_queue(&queue->proc_list, &wait); } while (bytes_read < count && !queue_empty()) { p = get_from_queue(); if (copy_to_user (buffer+bytes_read, (void *) &p, sizeof(p))) { bytes_read = -EFAULT; break; } bytes_read += sizeof(p); } if (bytes_read > 0) { file->f_dentry->d_inode->i_atime = CURRENT_TIME; return bytes_read; } if (signal_pending(current)) return -ERESTARTSYS; return bytes_read; } static ssize_t mk712_write(struct file *file, const char *buffer, size_t count, loff_t *ppos) { return -EINVAL; } struct file_operations mk712_fops = { owner: THIS_MODULE, read: mk712_read, write: mk712_write, poll: mk712_poll, ioctl: mk712_ioctl, open: mk712_open, release: mk712_close, fasync: mk712_fasync, }; static struct miscdevice mk712_touchscreen = { MK712_MINOR, "mk712_touchscreen", &mk712_fops }; int __init mk712_init(void) { #ifdef MODULE if (io) mk712_io = io; if (irq) mk712_irq = irq; #endif if(!request_region(mk712_io, 8, "mk712_touchscreen")) { printk("mk712: unable to get IO region\n"); return -ENODEV; } /* set up wait queue */ queue = (struct mk712_queue *) kmalloc(sizeof(*queue), GFP_KERNEL); if(queue == NULL) { release_region(mk712_io, 8); return -ENOMEM; } memset(queue, 0, sizeof(*queue)); queue->head = queue->tail = 0; init_waitqueue_head(&queue->proc_list); /* The MK712 is ISA and hard-coded to a particular IRQ, so the driver should keep the IRQ as long as it is loaded. */ if(request_irq(mk712_irq, mk712_interrupt, 0, "mk712_touchscreen", queue)) { printk("mk712: unable to get IRQ\n"); release_region(mk712_io, 8); kfree(queue); return -EBUSY; } /* register misc device */ if(misc_register(&mk712_touchscreen)<0) { release_region(mk712_io, 8); kfree(queue); free_irq(mk712_irq, queue); return -ENODEV; } return 0; } static void __exit mk712_exit(void) { misc_deregister(&mk712_touchscreen); release_region(mk712_io, 8); free_irq(mk712_irq, queue); kfree(queue); printk(KERN_INFO "mk712 touchscreen uninstalled\n"); } MODULE_AUTHOR("Daniel Quinlan"); MODULE_DESCRIPTION("MK712 touch screen driver"); MODULE_PARM(io, "i"); MODULE_PARM_DESC(io, "I/O base address of MK712 touch screen controller"); MODULE_PARM(irq, "i"); MODULE_PARM_DESC(irq, "IRQ of MK712 touch screen controller"); MODULE_LICENSE("GPL"); module_init(mk712_init); module_exit(mk712_exit); /* * Local variables: * c-file-style: "linux" * End: */