openwrtv4/target/linux/ep93xx/patches-2.6.36/003-ep93xx_touchscreen.patch

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---
arch/arm/mach-ep93xx/include/mach/hardware.h | 1
arch/arm/mach-ep93xx/include/mach/regs_touch.h | 95 ++
drivers/input/touchscreen/Kconfig | 5
drivers/input/touchscreen/Makefile | 1
drivers/input/touchscreen/ep93xx_ts.c | 1117 +++++++++++++++++++++++++
drivers/input/touchscreen/ep93xx_ts.h | 53 +
6 files changed, 1272 insertions(+)
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -153,6 +153,15 @@ config TOUCHSCREEN_EETI
To compile this driver as a module, choose M here: the
module will be called eeti_ts.
+config TOUCHSCREEN_EP93XX
+ tristate "EP93xx Touchscreen"
+ depends on ARM && INPUT && ARCH_EP93XX
+ help
+ Say Y here to enable support for EP93xx touch screen.
+
+ To compile this driver as a module, choose M here:
+ the module will be called ep93xx_ts.
+
config TOUCHSCREEN_FUJITSU
tristate "Fujitsu serial touchscreen"
select SERIO
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -21,6 +21,7 @@ obj-$(CONFIG_TOUCHSCREEN_HAMPSHIRE) += h
obj-$(CONFIG_TOUCHSCREEN_GUNZE) += gunze.o
obj-$(CONFIG_TOUCHSCREEN_EETI) += eeti_ts.o
obj-$(CONFIG_TOUCHSCREEN_ELO) += elo.o
+obj-$(CONFIG_TOUCHSCREEN_EP93XX) += ep93xx_ts.o
obj-$(CONFIG_TOUCHSCREEN_FUJITSU) += fujitsu_ts.o
obj-$(CONFIG_TOUCHSCREEN_INEXIO) += inexio.o
obj-$(CONFIG_TOUCHSCREEN_MC13783) += mc13783_ts.o
--- /dev/null
+++ b/drivers/input/touchscreen/ep93xx_ts.c
@@ -0,0 +1,1020 @@
+/*
+ * linux/drivers/input/touchscreen/ep93xx_ts.c
+ *
+ * Copyright (C) 2003-2004 Cirrus Corp.
+ *
+ * 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 <linux/module.h>
+#include <linux/types.h>
+#include <linux/delay.h>
+#include <linux/wait.h>
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/poll.h>
+#include <linux/miscdevice.h>
+#include <linux/init.h>
+#include <linux/compiler.h>
+#include <linux/timer.h>
+#include <linux/interrupt.h>
+#include <linux/syscalls.h>
+#include <linux/input.h>
+#include <asm/irq.h>
+#include <mach/hardware.h>
+#include <asm/io.h>
+
+/* This stuff should be in ep93xx-regs.h */
+#define EP93XX_TOUCHSCREEN_REG(x) (EP93XX_TOUCHSCREEN_BASE + (x))
+/* R/W touchscreen controller setup control register. */
+#define EP93XX_TOUCHSCREEN_SETUP EP93XX_TOUCHSCREEN_REG(0x00)
+/* R/W touchscreen controller max/min register. */
+#define EP93XX_TOUCHSCREEN_XYMAXMIN EP93XX_TOUCHSCREEN_REG(0x04)
+/* R touchscreen controller result register. */
+#define EP93XX_TOUCHSCREEN_XYRESULT EP93XX_TOUCHSCREEN_REG(0x08)
+/* LOCKED R/W touchscreen Switch Matrix control register. */
+#define EP93XX_TOUCHSCREEN_DISCHARGE EP93XX_TOUCHSCREEN_REG(0x0C)
+#define EP93XX_TOUCHSCREEN_XSAMPLE EP93XX_TOUCHSCREEN_REG(0x10)
+#define EP93XX_TOUCHSCREEN_YSAMPLE EP93XX_TOUCHSCREEN_REG(0x14)
+#define EP93XX_TOUCHSCREEN_DIRECT EP93XX_TOUCHSCREEN_REG(0x18)
+#define EP93XX_TOUCHSCREEN_DETECT EP93XX_TOUCHSCREEN_REG(0x1C)
+/* NA R/W touchscreen software lock register. */
+#define EP93XX_TOUCHSCREEN_SWLOCK EP93XX_TOUCHSCREEN_REG(0x20)
+/* R/W touchscreen setup control register #2. */
+#define EP93XX_TOUCHSCREEN_SETUP2 EP93XX_TOUCHSCREEN_REG(0x24)
+
+/* These are duplicated in mach-ep93xx/core.c */
+#define EP93XX_TIMER_REG(x) (EP93XX_TIMER_BASE + (x))
+#define EP93XX_TIMER2_LOAD EP93XX_TIMER_REG(0x20)
+#define EP93XX_TIMER2_VALUE EP93XX_TIMER_REG(0x24)
+#define EP93XX_TIMER2_CONTROL EP93XX_TIMER_REG(0x28)
+#define EP93XX_TIMER2_CLEAR EP93XX_TIMER_REG(0x2c)
+
+/*
+ * Register bit definitions
+ */
+#define TSSETUP_SDLY_MASK 0x000003FF
+#define TSSETUP_SDLY_SHIFT 0
+#define TSSETUP_NSMP_4 0x00000000
+#define TSSETUP_NSMP_8 0x00000400
+#define TSSETUP_NSMP_16 0x00000800
+#define TSSETUP_NSMP_32 0x00000C00
+#define TSSETUP_NSMP_MASK 0x00000C00
+#define TSSETUP_DEV_4 0x00000000
+#define TSSETUP_DEV_8 0x00001000
+#define TSSETUP_DEV_12 0x00002000
+#define TSSETUP_DEV_16 0x00003000
+#define TSSETUP_DEV_24 0x00004000
+#define TSSETUP_DEV_32 0x00005000
+#define TSSETUP_DEV_64 0x00006000
+#define TSSETUP_DEV_128 0x00007000
+#define TSSETUP_ENABLE 0x00008000
+#define TSSETUP_DLY_MASK 0x03FF0000
+#define TSSETUP_DLY_SHIFT 16
+#define TSSETUP_TDTCT 0x80000000
+
+#define TSMAXMIN_XMIN_MASK 0x000000FF
+#define TSMAXMIN_XMIN_SHIFT 0
+#define TSMAXMIN_YMIN_MASK 0x0000FF00
+#define TSMAXMIN_YMIN_SHIFT 8
+#define TSMAXMIN_XMAX_MASK 0x00FF0000
+#define TSMAXMIN_XMAX_SHIFT 16
+#define TSMAXMIN_YMAX_MASK 0xFF000000
+#define TSMAXMIN_YMAX_SHIFT 24
+
+#define TSXYRESULT_X_MASK 0x00000FFF
+#define TSXYRESULT_X_SHIFT 0
+#define TSXYRESULT_AD_MASK 0x0000FFFF
+#define TSXYRESULT_AD_SHIFT 0
+#define TSXYRESULT_Y_MASK 0x0FFF0000
+#define TSXYRESULT_Y_SHIFT 16
+#define TSXYRESULT_SDR 0x80000000
+
+#define TSX_SAMPLE_MASK 0x00003FFF
+#define TSX_SAMPLE_SHIFT 0x00
+#define TSY_SAMPLE_MASK 0x3FFF0000
+#define TSY_SAMPLE_SHIFT 0x10
+
+#define TSSETUP2_TINT 0x00000001
+#define TSSETUP2_NICOR 0x00000002
+#define TSSETUP2_PINT 0x00000004
+#define TSSETUP2_PENSTS 0x00000008
+#define TSSETUP2_PINTEN 0x00000010
+#define TSSETUP2_DEVINT 0x00000020
+#define TSSETUP2_DINTEN 0x00000040
+#define TSSETUP2_DTMEN 0x00000080
+#define TSSETUP2_DISDEV 0x00000100
+#define TSSETUP2_NSIGND 0x00000200
+#define TSSETUP2_S28EN 0x00000400
+#define TSSETUP2_RINTEN 0x00000800
+
+#define TSXYRESULT_SDR 0x80000000
+
+/*
+ * These are used as trigger levels to know when we have pen up/down.
+ * The rules:
+ * 1. TS_HEAVY_INV_PRESSURE < TS_LIGHT_INV_PRESSURE because these
+ * are Inverse pressure.
+ * 2. Any touch lighter than TS_LIGHT_INV_PRESSURE is a pen up.
+ * 3. Any touch heavier than TS_HEAVY_INV_PRESSURE is a pen down.
+ */
+#define TS_HEAVY_INV_PRESSURE 0xFE0 /* C00 */
+#define TS_LIGHT_INV_PRESSURE 0xFFF /* e00 */
+
+/*
+ * If the x, y, or inverse pressure changes more than these values
+ * between two succeeding points, the point is not reported.
+ */
+#define TS_MAX_VALID_XY_CHANGE 0x300
+#define TS_MAX_VALID_PRESSURE_CHANGE 0x100
+
+/*
+ * This is the minimum Z1 Value that is valid.
+ */
+#define MIN_Z1_VALUE 0x50
+
+/*
+ * Settling delay for taking each ADC measurement. Increase this
+ * if ts is jittery.
+ */
+#define EP93XX_TS_ADC_DELAY_USEC 2000
+
+/*
+ * Delay between TS points.
+ */
+#define EP93XX_TS_PER_POINT_DELAY_USEC 10000
+
+/*
+ * A few more macros...
+ */
+#define TSSETUP_DEFAULT (TSSETUP_NSMP_32 | TSSETUP_DEV_64 | \
+ ((128<<TSSETUP_SDLY_SHIFT) & TSSETUP_SDLY_MASK) | \
+ ((128<<TSSETUP_DLY_SHIFT) & TSSETUP_DLY_MASK))
+
+#define TSSETUP2_DEFAULT (TSSETUP2_NSIGND)
+
+/*
+ * For now, we use one of the minor numbers from the local/experimental
+ * range.
+ */
+#define EP93XX_TS_MINOR 240
+
+/*
+ * Static Declarations
+ */
+static unsigned int guiLastX, guiLastY;
+static unsigned int guiLastInvPressure;
+
+struct TouchScreenSample
+{
+ int currentX;
+ int currentY;
+ int currentButton;
+ int currentPressure;
+ struct timeval currentTime;
+};
+
+/*
+ * This must match the structure in tslib.
+ */
+struct ts_sample {
+ int x;
+ int y;
+ unsigned int pressure;
+ struct timeval tv;
+};
+
+static struct TouchScreenSample gSample;
+static int bFreshTouchData;
+static int bCurrentPenDown;
+
+static DECLARE_WAIT_QUEUE_HEAD(queue);
+static DECLARE_MUTEX(open_sem);
+static spinlock_t event_buffer_lock = SPIN_LOCK_UNLOCKED;
+static struct fasync_struct *ep93xx_fasync;
+
+/*
+ * Typedef Declarations
+ */
+typedef enum {
+ TS_MODE_UN_INITIALIZED,
+ TS_MODE_HARDWARE_SCAN,
+ TS_MODE_SOFT_SCAN
+} ts_mode_t;
+
+static ts_mode_t gScanningMode;
+
+typedef enum{
+ TS_STATE_STOPPED = 0,
+ TS_STATE_Z1,
+ TS_STATE_Z2,
+ TS_STATE_Y,
+ TS_STATE_X,
+ TS_STATE_DONE
+} ts_states_t;
+
+typedef struct
+{
+ unsigned int uiX;
+ unsigned int uiY;
+ unsigned int uiZ1;
+ unsigned int uiZ2;
+ ts_states_t state;
+} ts_struct_t;
+
+static ts_struct_t sTouch;
+
+/*
+ * From the spec, here's how to set up the touch screen's switch registers.
+ */
+typedef struct
+{
+ unsigned int uiDetect;
+ unsigned int uiDischarge;
+ unsigned int uiXSample;
+ unsigned int uiYSample;
+ unsigned int uiSwitchZ1;
+ unsigned int uiSwitchZ2;
+}SwitchStructType;
+
+/*
+ * Here's the switch settings for a 4-wire touchscreen. See the spec
+ * for how to handle a 4, 7, or 8-wire.
+ */
+const static SwitchStructType sSwitchSettings =
+/* s28en=0 */
+/* TSDetect TSDischarge TSXSample TSYSample SwitchZ1 SwitchZ2 */
+ {0x00403604, 0x0007fe04, 0x00081604, 0x00104601, 0x00101601, 0x00101608};
+
+/*
+ * Function declarations
+ */
+static void ep93xx_ts_set_direct(unsigned int uiADCSwitch);
+static irqreturn_t ep93xx_ts_isr(int irq, void *dev_id);
+static irqreturn_t ep93xx_timer2_isr(int irq, void *dev_id);
+static void ee93xx_ts_evt_add(int button, int dX, int dY, int Pressure);
+static ssize_t ep93xx_ts_read(struct file *filp, char *buf,
+ size_t count, loff_t *l);
+static unsigned int ep93xx_ts_poll(struct file *filp, poll_table *wait);
+static int ep93xx_ts_open(struct inode *inode, struct file *filp);
+static int ep93xx_ts_fasync(int fd, struct file *filp, int on);
+static int ep93xx_ts_release(struct inode *inode, struct file *filp);
+static ssize_t ep93xx_ts_write(struct file *file, const char *buffer,
+ size_t count, loff_t *ppos);
+static void ep93xx_ts_setup(void);
+static void ep93xx_ts_shutdown(void);
+int __init ep93xx_ts_init(void);
+void __exit ep93xx_ts_exit(void);
+static unsigned int CalculateInvPressure(void);
+static unsigned int ADCGetData(unsigned int uiSamples, unsigned int uiMaxDiff);
+static void TS_Soft_Scan_Mode(void);
+static void TS_Hardware_Scan_Mode(void);
+static void ProcessPointData(void);
+static void Set_Timer2_uSec(unsigned int Delay_mSec);
+static void Stop_Timer2(void);
+
+/*
+ * ep93xx_ts_isr
+ */
+static irqreturn_t ep93xx_ts_isr(int irq, void *dev_id)
+{
+ /*
+ * Note that we don't clear the interrupt here. The interrupt
+ * gets cleared in TS_Soft_Scan_Mode when the TS ENABLE
+ * bit is cleared.
+ */
+
+ /*
+ * Set the ts to manual polling mode and schedule a callback.
+ * That way we can return from the isr in a reasonable amount of
+ * time and process the touch in the callback after a brief delay.
+ */
+ TS_Soft_Scan_Mode();
+
+ return(IRQ_HANDLED);
+}
+
+/*
+ * Save the current ts 'event' in an atomic fashion.
+ */
+static void ee93xx_ts_evt_add(int buttons, int iX, int iY, int iPressure)
+{
+ /*
+ * Note the event, but use spinlocks to keep it from getting
+ * halfway read if we get interrupted.
+ */
+
+ spin_lock(&event_buffer_lock);
+
+ gSample.currentX = iX;
+ gSample.currentY = iY;
+ gSample.currentButton = buttons;
+ gSample.currentPressure = iPressure;
+ bFreshTouchData = 1;
+ do_gettimeofday(&gSample.currentTime);
+
+ spin_unlock(&event_buffer_lock);
+
+ kill_fasync(&ep93xx_fasync, SIGIO, POLL_IN);
+ wake_up_interruptible(&queue);
+}
+
+
+static ssize_t ep93xx_ts_read(struct file *filp, char *buf, size_t count, loff_t *l)
+{
+ unsigned short data[3];
+ struct ts_sample ts_data;
+ int iReturn = -EFAULT;
+
+ if (!bFreshTouchData)
+ {
+ iReturn = 0;
+ }
+ else if (count == sizeof(data))
+ {
+ spin_lock_irq(&event_buffer_lock);
+ bFreshTouchData = 0;
+ data[0] = gSample.currentX;
+ data[1] = gSample.currentY;
+ data[2] = gSample.currentButton;
+
+ spin_unlock_irq(&event_buffer_lock);
+
+ if (copy_to_user(buf, data, sizeof data))
+ return -EFAULT;
+
+ count -= sizeof(data);
+
+ /* return the # of bytes that got read */
+ iReturn = sizeof(data) ;
+ }
+ else if (count == sizeof(struct ts_sample) )
+ {
+ spin_lock_irq(&event_buffer_lock);
+ bFreshTouchData = 0;
+ ts_data.x = gSample.currentX;
+ ts_data.y = gSample.currentY;
+ ts_data.pressure = gSample.currentPressure;
+ ts_data.tv = gSample.currentTime;
+ spin_unlock_irq(&event_buffer_lock);
+
+ if (copy_to_user(buf, &ts_data, sizeof(struct ts_sample)))
+ {
+ iReturn = -EFAULT;
+ }
+ else
+ {
+ count -= sizeof(ts_data);
+ iReturn = sizeof(ts_data);
+ }
+ }
+
+ return iReturn;
+}
+
+static unsigned int ep93xx_ts_poll(struct file *filp, poll_table *wait)
+{
+ poll_wait(filp, &queue, wait);
+
+ if (bFreshTouchData)
+ {
+ return POLLIN | POLLRDNORM;
+ }
+
+ return 0;
+}
+
+static int ep93xx_ts_open(struct inode *inode, struct file *filp)
+{
+ if (down_trylock(&open_sem))
+ {
+ return -EBUSY;
+ }
+
+ ep93xx_ts_setup();
+
+ return 0;
+}
+
+/*
+ * Asynchronous I/O support.
+ */
+static int ep93xx_ts_fasync(int fd, struct file *filp, int on)
+{
+ int retval;
+
+ retval = fasync_helper(fd, filp, on, &ep93xx_fasync);
+ if (retval < 0)
+ {
+ return retval;
+ }
+
+ return 0;
+}
+
+static int ep93xx_ts_release(struct inode *inode, struct file *filp)
+{
+ Stop_Timer2();
+
+ /*
+ * Call our async I/O support to request that this file
+ * cease to be used for async I/O.
+ */
+ ep93xx_ts_fasync(-1, filp, 0);
+
+ ep93xx_ts_shutdown();
+
+ up(&open_sem);
+
+ return 0;
+}
+
+static ssize_t ep93xx_ts_write(struct file *file, const char *buffer, size_t count,
+ loff_t *ppos)
+{
+ return -EINVAL;
+}
+
+
+static int ep93xx_ts_ioctl(struct inode *inode, struct file *file, uint command, ulong u)
+{
+ static const int version = EV_VERSION;
+ static const u_int32_t bit =(1 << EV_ABS);
+ static const u_int32_t absbit = (1 << ABS_X) | (1 << ABS_Y) | (1 << ABS_PRESSURE);
+ int iReturn ;
+ int i = 0;
+
+ switch(command)
+ {
+ case EVIOCGVERSION:
+ i = copy_to_user((void __user *)u, (void *)version, sizeof(version));
+ iReturn = i ? -EFAULT : 0;
+ break;
+
+ case EVIOCGBIT(0,sizeof(u_int32_t) * 8) :
+ i = copy_to_user((void __user *)u, (void *)bit, sizeof(bit));
+ iReturn = i ? -EFAULT : 0;
+ break;
+
+ case EVIOCGBIT(EV_ABS, sizeof(absbit) * 8):
+ i = copy_to_user((void __user *)u, (void *)absbit, sizeof(absbit));
+ iReturn = i ? -EFAULT : 0;
+ break;
+ default:
+ iReturn = -1;
+ break;
+ }
+
+ return iReturn;
+}
+
+static struct file_operations ep93xx_ts_fops = {
+ owner: THIS_MODULE,
+ read: ep93xx_ts_read,
+ write: ep93xx_ts_write,
+ poll: ep93xx_ts_poll,
+ open: ep93xx_ts_open,
+ unlocked_ioctl: ep93xx_ts_ioctl,
+ release: ep93xx_ts_release,
+ fasync: ep93xx_ts_fasync,
+};
+
+static struct miscdevice ep93xx_ts_miscdev =
+{
+ EP93XX_TS_MINOR,
+ "ep93xx_ts",
+ &ep93xx_ts_fops
+};
+
+void ep93xx_ts_setup(void)
+{
+ unsigned int uiKTDIV, uiTSXYMaxMin;
+
+ /*
+ * Set the TSEN bit in KTDIV so that we are enabling the clock
+ * for the touchscreen.
+ */
+ uiKTDIV = __raw_readl(EP93XX_SYSCON_KEYTCHCLKDIV);
+ uiKTDIV |= EP93XX_SYSCON_KEYTCHCLKDIV_TSEN;
+ ep93xx_syscon_swlocked_write(uiKTDIV, EP93XX_SYSCON_KEYTCHCLKDIV);
+
+ /*
+ * Program the EP93XX_TOUCHSCREEN_SETUP and TSSetup2 registers.
+ */
+ __raw_writel(TSSETUP_DEFAULT, EP93XX_TOUCHSCREEN_SETUP);
+ __raw_writel(TSSETUP2_DEFAULT, EP93XX_TOUCHSCREEN_SETUP2);
+
+ /*
+ * Set the the touch settings.
+ */
+ __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
+ __raw_writel(sSwitchSettings.uiDischarge, EP93XX_TOUCHSCREEN_DIRECT);
+
+ __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
+ __raw_writel(sSwitchSettings.uiDischarge, EP93XX_TOUCHSCREEN_DISCHARGE);
+
+ __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
+ __raw_writel(sSwitchSettings.uiSwitchZ1, EP93XX_TOUCHSCREEN_XSAMPLE);
+
+ __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
+ __raw_writel(sSwitchSettings.uiSwitchZ2, EP93XX_TOUCHSCREEN_YSAMPLE);
+
+ __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
+ __raw_writel(sSwitchSettings.uiDetect, EP93XX_TOUCHSCREEN_DETECT);
+
+ /*
+ * X,YMin set to 0x40 = have to drag that many pixels for a new irq.
+ * X,YMax set to 0x40 = 1024 pixels is the maximum movement within the
+ * time scan limit.
+ */
+ uiTSXYMaxMin = (50 << TSMAXMIN_XMIN_SHIFT) & TSMAXMIN_XMIN_MASK;
+ uiTSXYMaxMin |= (50 << TSMAXMIN_YMIN_SHIFT) & TSMAXMIN_YMIN_MASK;
+ uiTSXYMaxMin |= (0xff << TSMAXMIN_XMAX_SHIFT) & TSMAXMIN_XMAX_MASK;
+ uiTSXYMaxMin |= (0xff << TSMAXMIN_YMAX_SHIFT) & TSMAXMIN_YMAX_MASK;
+ __raw_writel(uiTSXYMaxMin, EP93XX_TOUCHSCREEN_XYMAXMIN);
+
+ bCurrentPenDown = 0;
+ bFreshTouchData = 0;
+ guiLastX = 0;
+ guiLastY = 0;
+ guiLastInvPressure = 0xffffff;
+
+ /*
+ * Enable the touch screen scanning engine.
+ */
+ TS_Hardware_Scan_Mode();
+}
+
+/*
+ * ep93xx_ts_shutdown
+ *
+ */
+static void
+ep93xx_ts_shutdown(void)
+{
+ unsigned int uiKTDIV;
+
+ sTouch.state = TS_STATE_STOPPED;
+ Stop_Timer2();
+
+ /*
+ * Disable the scanning engine.
+ */
+ __raw_writel(0, EP93XX_TOUCHSCREEN_SETUP);
+ __raw_writel(0, EP93XX_TOUCHSCREEN_SETUP2);
+
+ /*
+ * Clear the TSEN bit in KTDIV so that we are disabling the clock
+ * for the touchscreen.
+ */
+ uiKTDIV = __raw_readl(EP93XX_SYSCON_KEYTCHCLKDIV);
+ uiKTDIV &= ~EP93XX_SYSCON_KEYTCHCLKDIV_TSEN;
+ ep93xx_syscon_swlocked_write(uiKTDIV, EP93XX_SYSCON_KEYTCHCLKDIV);
+
+} /* ep93xx_ts_shutdown */
+
+static irqreturn_t ep93xx_timer2_isr(int irq, void *dev_id)
+{
+ switch(sTouch.state)
+ {
+ case TS_STATE_STOPPED:
+ TS_Hardware_Scan_Mode();
+ break;
+
+ /*
+ * Get the Z1 value for pressure measurement and set up
+ * the switch register for getting the Z2 measurement.
+ */
+ case TS_STATE_Z1:
+ Set_Timer2_uSec(EP93XX_TS_ADC_DELAY_USEC);
+ sTouch.uiZ1 = ADCGetData(2, 200);
+ ep93xx_ts_set_direct(sSwitchSettings.uiSwitchZ2);
+ sTouch.state = TS_STATE_Z2;
+ break;
+
+ /*
+ * Get the Z2 value for pressure measurement and set up
+ * the switch register for getting the Y measurement.
+ */
+ case TS_STATE_Z2:
+ sTouch.uiZ2 = ADCGetData(2, 200);
+ ep93xx_ts_set_direct(sSwitchSettings.uiYSample);
+ sTouch.state = TS_STATE_Y;
+ break;
+
+ /*
+ * Get the Y value and set up the switch register for
+ * getting the X measurement.
+ */
+ case TS_STATE_Y:
+ sTouch.uiY = ADCGetData(4, 20);
+ ep93xx_ts_set_direct(sSwitchSettings.uiXSample);
+ sTouch.state = TS_STATE_X;
+ break;
+
+ /*
+ * Read the X value. This is the last of the 4 adc values
+ * we need so we continue on to process the data.
+ */
+ case TS_STATE_X:
+ Stop_Timer2();
+
+ sTouch.uiX = ADCGetData(4, 20);
+
+ __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
+ __raw_writel(sSwitchSettings.uiDischarge, EP93XX_TOUCHSCREEN_DIRECT);
+
+ sTouch.state = TS_STATE_DONE;
+
+ /*
+ * Process this set of ADC readings.
+ */
+ ProcessPointData();
+
+ break;
+
+ /*
+ * Shouldn't get here. But if we do, we can recover...
+ */
+ case TS_STATE_DONE:
+ TS_Hardware_Scan_Mode();
+ break;
+ }
+
+ /*
+ * Clear the timer2 interrupt.
+ */
+ __raw_writel(1, EP93XX_TIMER2_CLEAR);
+ return(IRQ_HANDLED);
+}
+
+/*---------------------------------------------------------------------
+ * ProcessPointData
+ *
+ * This routine processes the ADC data into usable point data and then
+ * puts the driver into hw or sw scanning mode before returning.
+ *
+ * We calculate inverse pressure (lower number = more pressure) then
+ * do a hystheresis with the two pressure values 'light' and 'heavy'.
+ *
+ * If we are above the light, we have pen up.
+ * If we are below the heavy we have pen down.
+ * As long as the pressure stays below the light, pen stays down.
+ * When we get above the light again, pen goes back up.
+ *
+ */
+static void ProcessPointData(void)
+{
+ int bValidPoint = 0;
+ unsigned int uiXDiff, uiYDiff, uiInvPressureDiff;
+ unsigned int uiInvPressure;
+
+ /*
+ * Calculate the current pressure.
+ */
+ uiInvPressure = CalculateInvPressure();
+
+ /*
+ * If pen pressure is so light that it is greater than the 'max' setting
+ * then we consider this to be a pen up.
+ */
+ if (uiInvPressure >= TS_LIGHT_INV_PRESSURE)
+ {
+ bCurrentPenDown = 0;
+ ee93xx_ts_evt_add(0, guiLastX, guiLastY, 0);
+ TS_Hardware_Scan_Mode();
+ return;
+ }
+
+ /*
+ * Hysteresis:
+ * If the pen pressure is hard enough to be less than the 'min' OR
+ * the pen is already down and is still less than the 'max'...
+ */
+ if ((uiInvPressure < TS_HEAVY_INV_PRESSURE) ||
+ (bCurrentPenDown && (uiInvPressure < TS_LIGHT_INV_PRESSURE)))
+ {
+ if (bCurrentPenDown)
+ {
+ /*
+ * If pen was previously down, check the difference between
+ * the last sample and this one... if the difference between
+ * samples is too great, ignore the sample.
+ */
+ uiXDiff = abs(guiLastX - sTouch.uiX);
+ uiYDiff = abs(guiLastY - sTouch.uiY);
+ uiInvPressureDiff = abs(guiLastInvPressure - uiInvPressure);
+
+ if (uiXDiff < TS_MAX_VALID_XY_CHANGE
+ && uiYDiff < TS_MAX_VALID_XY_CHANGE
+ && uiInvPressureDiff < TS_MAX_VALID_PRESSURE_CHANGE)
+ {
+ bValidPoint = 1;
+ }
+ }
+ else
+ {
+ bValidPoint = 1;
+ }
+
+ /*
+ * If either the pen was put down or dragged make a note of it.
+ */
+ if (bValidPoint)
+ {
+ guiLastX = sTouch.uiX;
+ guiLastY = sTouch.uiY;
+ guiLastInvPressure = uiInvPressure;
+ bCurrentPenDown = 1;
+ ee93xx_ts_evt_add(1, sTouch.uiX, sTouch.uiY,
+ 0x7000000 / uiInvPressure);
+ }
+
+ TS_Soft_Scan_Mode();
+ return;
+ }
+
+ TS_Hardware_Scan_Mode();
+}
+
+static void ep93xx_ts_set_direct(unsigned int uiADCSwitch)
+{
+ unsigned int uiResult;
+
+ /*
+ * Set the switch settings in the direct register.
+ */
+ __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
+ __raw_writel(uiADCSwitch, EP93XX_TOUCHSCREEN_DIRECT);
+
+ /*
+ * Read and throw away the first sample.
+ */
+ do {
+ uiResult = __raw_readl(EP93XX_TOUCHSCREEN_XYRESULT);
+ } while (!(uiResult & TSXYRESULT_SDR));
+
+}
+
+static unsigned int ADCGetData(unsigned int uiSamples, unsigned int uiMaxDiff)
+{
+ unsigned int uiResult, uiValue, uiCount, uiLowest, uiHighest, uiSum, uiAve;
+
+ do
+ {
+ /*
+ * Initialize our values.
+ */
+ uiLowest = 0xfffffff;
+ uiHighest = 0;
+ uiSum = 0;
+
+ for (uiCount = 0; uiCount < uiSamples; uiCount++)
+ {
+ /*
+ * Read the touch screen four more times and average.
+ */
+ do {
+ uiResult = __raw_readl(EP93XX_TOUCHSCREEN_XYRESULT);
+ } while (!(uiResult & TSXYRESULT_SDR));
+
+ uiValue = (uiResult & TSXYRESULT_AD_MASK) >> TSXYRESULT_AD_SHIFT;
+ uiValue = ((uiValue >> 4) + ((1 + TSXYRESULT_X_MASK)>>1)) & TSXYRESULT_X_MASK;
+
+ /*
+ * Add up the values.
+ */
+ uiSum += uiValue;
+
+ /*
+ * Get the lowest and highest values.
+ */
+ if (uiValue < uiLowest)
+ {
+ uiLowest = uiValue;
+ }
+ if (uiValue > uiHighest)
+ {
+ uiHighest = uiValue;
+ }
+ }
+ } while ((uiHighest - uiLowest) > uiMaxDiff);
+
+ /*
+ * Calculate the Average value.
+ */
+ uiAve = uiSum / uiSamples;
+
+ return uiAve;
+}
+
+/*
+ * CalculateInvPressure
+ *
+ * Is the Touch Valid. Touch is not valid if the X or Y value is not
+ * in range and the pressure is not enough.
+ *
+ * Touch resistance can be measured by the following formula:
+ *
+ * Rx * X * Z2
+ * Rtouch = --------- * (-- - 1)
+ * 4096 Z1
+ *
+ * This is simplified in the ration of Rtouch to Rx. The lower the value, the
+ * higher the pressure.
+ *
+ * Z2
+ * InvPressure = X * (-- - 1)
+ * Z1
+ */
+static unsigned int CalculateInvPressure(void)
+{
+ unsigned int uiInvPressure;
+
+ /*
+ * Check to see if the point is valid.
+ */
+ if (sTouch.uiZ1 < MIN_Z1_VALUE)
+ {
+ uiInvPressure = 0x10000;
+ }
+
+ /*
+ * Can omit the pressure calculation if you need to get rid of the division.
+ */
+ else
+ {
+ uiInvPressure = ((sTouch.uiX * sTouch.uiZ2) / sTouch.uiZ1) - sTouch.uiX;
+ }
+
+ return uiInvPressure;
+}
+
+/*
+ * TS_Hardware_Scan_Mode
+ *
+ * Enables the ep93xx ts scanning engine so that when the pen goes down
+ * we will get an interrupt.
+ */
+static void TS_Hardware_Scan_Mode(void)
+{
+ unsigned int uiDevCfg;
+
+ /*
+ * Disable the soft scanning engine.
+ */
+ sTouch.state = TS_STATE_STOPPED;
+ Stop_Timer2();
+
+ /*
+ * Clear the TIN (Touchscreen INactive) bit so we can go to
+ * automatic scanning mode.
+ */
+ uiDevCfg = __raw_readl(EP93XX_SYSCON_DEVCFG);
+ ep93xx_syscon_swlocked_write(uiDevCfg & ~EP93XX_SYSCON_DEVCFG_TIN,
+ EP93XX_SYSCON_DEVCFG);
+
+ /*
+ * Enable the touch screen scanning state machine by setting
+ * the ENABLE bit.
+ */
+ __raw_writel(TSSETUP_DEFAULT | TSSETUP_ENABLE, EP93XX_TOUCHSCREEN_SETUP);
+
+ /*
+ * Set the flag to show that we are in interrupt mode.
+ */
+ gScanningMode = TS_MODE_HARDWARE_SCAN;
+
+ /*
+ * Initialize EP93XX_TOUCHSCREEN_SETUP2 register.
+ */
+ __raw_writel(TSSETUP2_DEFAULT, EP93XX_TOUCHSCREEN_SETUP2);
+
+}
+
+/*
+ * TS_Soft_Scan_Mode
+ *
+ * Sets the touch screen to manual polling mode.
+ */
+static void TS_Soft_Scan_Mode(void)
+{
+ unsigned int uiDevCfg;
+
+ if (gScanningMode != TS_MODE_SOFT_SCAN)
+ {
+ /*
+ * Disable the touch screen scanning state machine by clearing
+ * the ENABLE bit.
+ */
+ __raw_writel(TSSETUP_DEFAULT, EP93XX_TOUCHSCREEN_SETUP);
+
+ /*
+ * Set the TIN bit so we can do manual touchscreen polling.
+ */
+ uiDevCfg = __raw_readl(EP93XX_SYSCON_DEVCFG);
+ ep93xx_syscon_swlocked_write(uiDevCfg | EP93XX_SYSCON_DEVCFG_TIN,
+ EP93XX_SYSCON_DEVCFG);
+ }
+
+ /*
+ * Set the switch register up for the first ADC reading
+ */
+ ep93xx_ts_set_direct(sSwitchSettings.uiSwitchZ1);
+
+ /*
+ * Initialize our software state machine to know which ADC
+ * reading to take
+ */
+ sTouch.state = TS_STATE_Z1;
+
+ /*
+ * Set the timer so after a mSec or two settling delay it will
+ * take the first ADC reading.
+ */
+ Set_Timer2_uSec(EP93XX_TS_PER_POINT_DELAY_USEC);
+
+ /*
+ * Note that we are in sw scanning mode not hw scanning mode.
+ */
+ gScanningMode = TS_MODE_SOFT_SCAN;
+
+}
+
+static void Set_Timer2_uSec(unsigned int uiDelay_uSec)
+{
+ unsigned int uiClockTicks;
+
+ /*
+ * Stop timer 2
+ */
+ __raw_writel(0, EP93XX_TIMER2_CONTROL);
+
+ uiClockTicks = ((uiDelay_uSec * 508) + 999) / 1000;
+ __raw_writel(uiClockTicks, EP93XX_TIMER2_LOAD);
+ __raw_writel(uiClockTicks, EP93XX_TIMER2_VALUE);
+
+ /*
+ * Set up Timer 2 for 508 kHz clock and periodic mode.
+ */
+ __raw_writel(0xC8, EP93XX_TIMER2_CONTROL);
+
+}
+
+static void Stop_Timer2(void)
+{
+ __raw_writel(0, EP93XX_TIMER2_CONTROL);
+}
+
+/*
+ * Initialization and exit routines
+ */
+int __init ep93xx_ts_init(void)
+{
+ int retval;
+
+ retval = request_irq(IRQ_EP93XX_TOUCH, ep93xx_ts_isr,
+ IRQF_DISABLED, "ep93xx_ts", 0);
+ if (retval)
+ {
+ printk(KERN_WARNING "ep93xx_ts: failed to get touchscreen IRQ\n");
+ return retval;
+ }
+
+ retval = request_irq(IRQ_EP93XX_TIMER2, ep93xx_timer2_isr,
+ IRQF_DISABLED, "ep93xx_timer2", 0);
+ if (retval)
+ {
+ printk(KERN_WARNING "ep93xx_ts: failed to get timer2 IRQ\n");
+ free_irq(IRQ_EP93XX_TOUCH, 0);
+ return retval;
+ }
+
+ misc_register(&ep93xx_ts_miscdev);
+
+ sTouch.state = TS_STATE_STOPPED;
+ gScanningMode = TS_MODE_UN_INITIALIZED;
+
+ printk(KERN_NOTICE "ep93xx touchscreen driver configured for 4-wire operation\n");
+
+ return 0;
+}
+
+void __exit ep93xx_ts_exit(void)
+{
+ Stop_Timer2();
+
+ free_irq(IRQ_EP93XX_TOUCH, 0);
+ free_irq(IRQ_EP93XX_TIMER2, 0);
+
+ misc_deregister(&ep93xx_ts_miscdev);
+}
+
+module_init(ep93xx_ts_init);
+module_exit(ep93xx_ts_exit);
+
+MODULE_DESCRIPTION("Cirrus EP93xx touchscreen driver");
+MODULE_SUPPORTED_DEVICE("touchscreen/ep93xx");
+MODULE_LICENSE("GPL");