Re: [PATCH] adding the ICS MK712 touchscreen driver to 2.6

[Vojtech Pavlik <vojtech@suse.de>]

On Sat, Feb 05, 2005 at 06:00:33PM -0500, Dmitry Torokhov wrote:

> > I converted it to a proper input driver for you. ;) Can you check it if
> > it still works?
> > 
> > +static irqreturn_t mk712_interrupt(int irq, void *dev_id, struct pt_regs *regs)
> > +{
> > +        unsigned char status;
> > +        static int debounce = 1;
> > +	static unsigned short last_x;
> > +	static unsigned short last_y;
> > +
> > +	input_regs(&mk712_dev, regs);
> > +
> > +        status = inb(mk712_io + MK712_STATUS);
> > +
> > +	if (~status & MK712_CONVERSION_COMPLETE) {
> > +                debounce = 1;
> > +		goto end;
> > +	}
> > +
> > +	if (~status & MK712_STATUS_TOUCH)
> > +	{
> > +                debounce = 1;
> > +		input_report_key(&mk712_dev, BTN_TOUCH, 0);
> > +		goto end;
> > +	}
> > +
> > +        if (debounce)
> > +        {
> > +		debounce = 0;
> > +		goto end;
> > +        }
> > +
> > +	input_report_key(&mk712_dev, BTN_TOUCH, 1);
> > +	input_report_abs(&mk712_dev, ABS_X, last_x);
> > +	input_report_abs(&mk712_dev, ABS_Y, last_y);
> 
> Severe TAB vs. space damage...
> 
> > +static int mk712_open(struct input_dev *dev)
> > +{
> > +	
> > +	if (mk712_used++)
> > +		return 0;
> > +
> > +	outb(0, mk712_io + MK712_CONTROL); /* Reset */
> > +
> 
> We really should stop ignoring races and locking issues. Atomic perhaps?

You're right, as usual. ;) How about this one? The spinlock also
protects from concurrent hardware register access. I'm always surprised
how much code the input API saves when converting a driver ...

ChangeSet@1.2112, 2005-02-06 10:13:52+01:00, vojtech@silver.ucw.cz
  input: New driver for ICS MicroClock MK712 TouchScreens.
  
  Signed-off-by: Vojtech Pavlik <vojtech@suse.cz>


 Kconfig  |   11 +++
 Makefile |    3 
 mk712.c  |  222 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 235 insertions(+), 1 deletion(-)


diff -Nru a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
--- a/drivers/input/touchscreen/Kconfig	2005-02-06 10:24:14 +01:00
+++ b/drivers/input/touchscreen/Kconfig	2005-02-06 10:24:14 +01:00
@@ -48,4 +48,15 @@
 	  To compile this driver as a module, choose M here: the
 	  module will be called gunze.
 
+config TOUCHSCREEN_MK712
+	tristate "ICS MicroClock MK712 touchscreen"
+	help
+	  Say Y here if you have the ICS MicroClock 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.
+
 endif
diff -Nru a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
--- a/drivers/input/touchscreen/Makefile	2005-02-06 10:24:14 +01:00
+++ b/drivers/input/touchscreen/Makefile	2005-02-06 10:24:14 +01:00
@@ -5,5 +5,6 @@
 # Each configuration option enables a list of files.
 
 obj-$(CONFIG_TOUCHSCREEN_BITSY)	+= h3600_ts_input.o
-obj-$(CONFIG_TOUCHSCREEN_GUNZE)	+= gunze.o
 obj-$(CONFIG_TOUCHSCREEN_CORGI)	+= corgi_ts.o
+obj-$(CONFIG_TOUCHSCREEN_GUNZE)	+= gunze.o
+obj-$(CONFIG_TOUCHSCREEN_MK712)	+= mk712.o
diff -Nru a/drivers/input/touchscreen/mk712.c b/drivers/input/touchscreen/mk712.c
--- /dev/null	Wed Dec 31 16:00:00 196900
+++ b/drivers/input/touchscreen/mk712.c	2005-02-06 10:24:14 +01:00
@@ -0,0 +1,222 @@
+/*
+ * ICS MK712 touchscreen controller driver
+ *
+ * Copyright (c) 1999-2002 Transmeta Corporation
+ * Copyright (c) 2005 Rick Koch <n1gp@hotmail.com>
+ * Copyright (c) 2005 Vojtech Pavlik <vojtech@suse.cz>
+ */
+
+/*
+ * 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.
+ */
+
+/*
+ * This driver supports the ICS MicroClock MK712 TouchScreen controller,
+ * found in Gateway AOL Connected Touchpad computers.
+ *
+ * Documentation for ICS MK712 can be found at:
+ * 	http://www.icst.com/pdf/mk712.pdf
+ */
+
+/*
+ * 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
+ * 2005-02-05: Rewritten for the input layer, Vojtech Pavlik
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/ioport.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+#include <asm/io.h>
+
+MODULE_AUTHOR("Daniel Quinlan <quinlan@pathname.com>, Vojtech Pavlik <vojtech@suse.cz>");
+MODULE_DESCRIPTION("ICS MicroClock MK712 TouchScreen driver");
+MODULE_LICENSE("GPL");
+
+static unsigned int mk712_io = 0x260;	/* Also 0x200, 0x208, 0x300 */
+module_param_named(io, mk712_io, uint, 0);
+MODULE_PARM_DESC(io, "I/O base address of MK712 touchscreen controller");
+
+static unsigned int mk712_irq = 10;	/* Also 12, 14, 15 */
+module_param_named(irq, mk712_irq, uint, 0);
+MODULE_PARM_DESC(irq, "IRQ of MK712 touchscreen controller");
+
+/* eight 8-bit registers */
+#define MK712_STATUS		0
+#define MK712_X			2
+#define MK712_Y			4
+#define MK712_CONTROL		6
+#define MK712_RATE		7
+
+/* status */
+#define	MK712_STATUS_TOUCH			0x10
+#define	MK712_CONVERSION_COMPLETE		0x80
+
+/* control */
+#define MK712_ENABLE_INT			0x01
+#define MK712_INT_ON_CONVERSION_COMPLETE	0x02
+#define MK712_INT_ON_CHANGE_IN_TOUCH_STATUS	0x04
+#define MK712_ENABLE_PERIODIC_CONVERSIONS	0x10
+#define MK712_READ_ONE_POINT			0x20
+#define MK712_POWERUP				0x40
+
+static int mk712_used = 0;
+static struct input_dev mk712_dev;
+static DEFINE_SPINLOCK(mk712_lock);
+
+static irqreturn_t mk712_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+	unsigned char status;
+	static int debounce = 1;
+	static unsigned short last_x;
+	static unsigned short last_y;
+
+	spin_lock(&mk712_lock);
+	input_regs(&mk712_dev, regs);
+
+	status = inb(mk712_io + MK712_STATUS);
+
+	if (~status & MK712_CONVERSION_COMPLETE) {
+		debounce = 1;
+		goto end;
+	}
+
+	if (~status & MK712_STATUS_TOUCH)
+	{
+		debounce = 1;
+		input_report_key(&mk712_dev, BTN_TOUCH, 0);
+		goto end;
+	}
+
+	if (debounce)
+	{
+		debounce = 0;
+		goto end;
+	}
+
+	input_report_key(&mk712_dev, BTN_TOUCH, 1);
+	input_report_abs(&mk712_dev, ABS_X, last_x);
+	input_report_abs(&mk712_dev, ABS_Y, last_y);
+
+end:
+
+	last_x =  inw(mk712_io + MK712_X) & 0x0fff;
+	last_y = (inw(mk712_io + MK712_Y) & 0x0fff) * 3 / 4;
+	input_sync(&mk712_dev);
+	spin_unlock(&mk712_lock);
+	return IRQ_HANDLED;
+}
+
+static int mk712_open(struct input_dev *dev)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&mk712_lock, flags);
+
+	if (!mk712_used++) {
+
+		outb(0, mk712_io + MK712_CONTROL); /* Reset */
+
+		outb(MK712_ENABLE_INT | MK712_INT_ON_CONVERSION_COMPLETE |
+			MK712_INT_ON_CHANGE_IN_TOUCH_STATUS |
+			MK712_ENABLE_PERIODIC_CONVERSIONS |
+			MK712_POWERUP, mk712_io + MK712_CONTROL);
+
+		outb(10, mk712_io + MK712_RATE); /* 187 points per second */
+	}
+
+	spin_unlock_irqrestore(&mk712_lock, flags);
+
+	return 0;
+}
+
+static void mk712_close(struct input_dev *dev)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&mk712_lock, flags);
+
+	if (!--mk712_used)
+		outb(0, mk712_io + MK712_CONTROL);
+
+	spin_unlock_irqrestore(&mk712_lock, flags);
+}
+
+static struct input_dev mk712_dev = {
+	.evbit   = { BIT(EV_KEY) | BIT(EV_ABS) },
+	.keybit  = { [LONG(BTN_LEFT)] = BIT(BTN_TOUCH) },
+	.absbit  = { BIT(ABS_X) | BIT(ABS_Y) },
+	.open    = mk712_open,
+	.close   = mk712_close,
+	.name    = "ICS MicroClock MK712 TouchScreen",
+	.phys    = "isa0260/input0",
+	.absmin  = { [ABS_X] = 0, [ABS_Y] = 0 },
+	.absmax  = { [ABS_X] = 0xfff, [ABS_Y] = 0xbff },
+	.absfuzz = { [ABS_X] = 88, [ABS_Y] = 88 },
+	.id      = {
+		.bustype = BUS_ISA,
+		.vendor  = 0x0005,
+		.product = 0x0001,
+		.version = 0x0100,
+	},
+};
+
+int __init mk712_init(void)
+{
+
+	if(!request_region(mk712_io, 8, "mk712"))
+	{
+		printk(KERN_WARNING "mk712: unable to get IO region\n");
+		return -ENODEV;
+	}
+
+	outb(0, mk712_io + MK712_CONTROL);
+
+	if ((inw(mk712_io + MK712_X) & 0xf000) ||	/* Sanity check */
+	    (inw(mk712_io + MK712_Y) & 0xf000) ||
+	    (inw(mk712_io + MK712_STATUS) & 0xf333)) {
+		printk(KERN_WARNING "mk712: device not present\n");
+		release_region(mk712_io, 8);
+		return -ENODEV;
+	}
+
+	if(request_irq(mk712_irq, mk712_interrupt, 0, "mk712", &mk712_dev))
+	{
+		printk(KERN_WARNING "mk712: unable to get IRQ\n");
+		release_region(mk712_io, 8);
+		return -EBUSY;
+	}
+
+	input_register_device(&mk712_dev);
+
+	printk(KERN_INFO "input: ICS MicroClock MK712 TouchScreen at %#x irq %d\n", mk712_io, mk712_irq);
+
+	return 0;
+}
+
+static void __exit mk712_exit(void)
+{
+	input_unregister_device(&mk712_dev);
+	free_irq(mk712_irq, &mk712_dev);
+	release_region(mk712_io, 8);
+}
+
+module_init(mk712_init);
+module_exit(mk712_exit);

-- 
Vojtech Pavlik
SuSE Labs, SuSE CR