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From: Vojtech Pavlik <vojtech@suse.de>
To: Richard Koch <n1gp@hotmail.com>
Cc: linux-kernel@vger.kernel.org,
	linux-input@atrey.karlin.mff.cuni.cz, torvalds@osdl.org,
	trivial@rustcorp.com.au
Subject: Re: [PATCH] adding the ICS MK712 touchscreen driver to 2.6
Date: Sat, 5 Feb 2005 20:31:39 +0100	[thread overview]
Message-ID: <20050205193139.GW2711@ucw.cz> (raw)
In-Reply-To: <BAY16-F34ACC3DA65154E040BEC5987800@phx.gbl>

On Wed, Jan 19, 2005 at 04:18:49PM -0500, Richard Koch wrote:
> Please include the patch below to bring the ICS MK712 touchscreen controller
> support, which is in kernel 2.4, in to kernel 2.6.
> 
> This patch was constructed and applied to kernel version 2.6.10 and tested
> successfully on several Gateway AOL Connected Touchpad computers.
> 
> This was based on the mk712.c 2.4.28 version. No functional changes applied 
> only minor
> changes to conform to the 2.6 build structure. I choose to place the driver 
> under
> input/touchscreen as this seemed most appropriate.
> 
> By making a contribution to this project, I certify that:
> 
> The contribution is based upon previous work that, to the best
> of my knowledge, is covered under an appropriate open source
> license and I have the right under that license to submit that
> work with modifications, whether created in whole or in part
> by me, under the same open source license (unless I am
> permitted to submit under a different license), as indicated
> in the file.
> 
> Signed-off-by: Rick Koch <n1gp@hotmail.com>
> 
> patch also available at: http://home.comcast.net/~n1gp/mk712_2.6_patch

Can you re-do the patch to be a proper input device instead of a misc
device driver? Then I'll gladly accept it.

> ===========================================
> 
> 
> diff -upN -X dontdiff linux-2.6.10/drivers/input/touchscreen/Kconfig 
> linux-2.6.10.mk712/drivers/input/touchscreen/Kconfig
> --- linux-2.6.10/drivers/input/touchscreen/Kconfig	2004-12-24 
> 16:34:45.000000000 -0500
> +++ linux-2.6.10.mk712/drivers/input/touchscreen/Kconfig	2005-01-18 
> 15:30:49.000000000 -0500
> @@ -35,3 +35,15 @@ config TOUCHSCREEN_GUNZE
> 	  To compile this driver as a module, choose M here: the
> 	  module will be called gunze.
> 
> +config TOUCHSCREEN_MK712
> +	tristate "ICS Mk712 touchscreen controller chip support"
> +	depends on INPUT && INPUT_TOUCHSCREEN
> +	help
> +	  Say Y here if you have the ICS Mk712 touchscreen controller
> +	  chip in your system.
> +
> +	  If unsure, say N.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called mk712.
> +
> diff -upN -X dontdiff linux-2.6.10/drivers/input/touchscreen/Makefile 
> linux-2.6.10.mk712/drivers/input/touchscreen/Makefile
> --- linux-2.6.10/drivers/input/touchscreen/Makefile	2004-12-24 
> 16:35:28.000000000 -0500
> +++ linux-2.6.10.mk712/drivers/input/touchscreen/Makefile	2005-01-18 
> 15:42:43.000000000 -0500
> @@ -6,3 +6,4 @@
> 
> obj-$(CONFIG_TOUCHSCREEN_BITSY)	+= h3600_ts_input.o
> obj-$(CONFIG_TOUCHSCREEN_GUNZE)	+= gunze.o
> +obj-$(CONFIG_TOUCHSCREEN_MK712)	+= mk712.o
> diff -upN -X dontdiff linux-2.6.10/drivers/input/touchscreen/mk712.c 
> linux-2.6.10.mk712/drivers/input/touchscreen/mk712.c
> --- linux-2.6.10/drivers/input/touchscreen/mk712.c	1969-12-31 
> 19:00:00.000000000 -0500
> +++ linux-2.6.10.mk712/drivers/input/touchscreen/mk712.c	2005-01-18 
> 17:45:56.000000000 -0500
> @@ -0,0 +1,507 @@
> +/* -*- 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 <alan@redhat.com>
> + *	       Fixed multi open race, fixed memory checks, fixed resource
> + *	       allocation, fixed close/powerdown bug, switched to new init
> + * 2005-01-18: Ported to 2.6 from 2.4.28, Rick Koch
> + *
> + * 
> ------------------------------------------------------------------------- */
> +
> +#include <linux/module.h>
> +
> +#include <linux/kernel.h>
> +#include <linux/sched.h>
> +#include <linux/init.h>
> +#include <linux/signal.h>
> +#include <linux/errno.h>
> +#include <linux/mm.h>
> +#include <linux/poll.h>
> +#include <linux/miscdevice.h>
> +#include <linux/random.h>
> +#include <linux/delay.h>
> +#include <linux/ioport.h>
> +#include <linux/slab.h>
> +#include <linux/interrupt.h>
> +
> +#include <asm/io.h>
> +#include <asm/uaccess.h>
> +#include <asm/system.h>
> +#include <asm/irq.h>
> +
> +#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 irqreturn_t 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 IRQ_HANDLED;
> +	}
> +	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 IRQ_HANDLED;
> +	}
> +
> +        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 IRQ_HANDLED;
> +        }
> +#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);
> +        return IRQ_HANDLED;
> +}
> +
> +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:
> + */
> diff -upN -X dontdiff linux-2.6.10/include/linux/miscdevice.h 
> linux-2.6.10.mk712/include/linux/miscdevice.h
> --- linux-2.6.10/include/linux/miscdevice.h	2004-12-24 
> 16:34:58.000000000 -0500
> +++ linux-2.6.10.mk712/include/linux/miscdevice.h	2005-01-18 
> 11:27:59.000000000 -0500
> @@ -12,6 +12,7 @@
> #define APOLLO_MOUSE_MINOR 7
> #define PC110PAD_MINOR 9
> /*#define ADB_MOUSE_MINOR 10	FIXME OBSOLETE */
> +#define MK712_MINOR             15      /* MK712 touch screen */
> #define WATCHDOG_MINOR		130	/* Watchdog timer     */
> #define TEMP_MINOR		131	/* Temperature Sensor */
> #define RTC_MINOR 135
> 
> 
> 

-- 
Vojtech Pavlik
SuSE Labs, SuSE CR

  parent reply	other threads:[~2005-02-05 19:33 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-01-19 21:18 [PATCH] adding the ICS MK712 touchscreen driver to 2.6 Richard Koch
2005-01-20 18:04 ` Dmitry Torokhov
2005-02-05 19:31 ` Vojtech Pavlik [this message]
2005-02-05 21:02 ` Vojtech Pavlik
2005-02-05 23:00   ` Dmitry Torokhov
2005-02-06  9:25     ` Vojtech Pavlik
2005-02-06 17:53       ` Dmitry Torokhov
  -- strict thread matches above, loose matches on Subject: below --
2005-02-11 15:50 Richard Koch
2005-02-11 16:08 ` Vojtech Pavlik

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