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

   1 ---
   2  arch/arm/mach-ep93xx/include/mach/hardware.h   |    1
   3  arch/arm/mach-ep93xx/include/mach/regs_touch.h |   95 ++
   4  drivers/input/touchscreen/Kconfig              |    5
   5  drivers/input/touchscreen/Makefile             |    1
   6  drivers/input/touchscreen/ep93xx_ts.c          | 1117 +++++++++++++++++++++++++
   7  drivers/input/touchscreen/ep93xx_ts.h          |   53 +
   8  6 files changed, 1272 insertions(+)
   9
  10 --- a/drivers/input/touchscreen/Kconfig
  11 +++ b/drivers/input/touchscreen/Kconfig
  12 @@ -153,6 +153,15 @@ config TOUCHSCREEN_EETI
  13           To compile this driver as a module, choose M here: the
  14           module will be called eeti_ts.
  15
  16 +config TOUCHSCREEN_EP93XX
  17 +       tristate "EP93xx Touchscreen"
  18 +       depends on ARM && INPUT && ARCH_EP93XX
  19 +       help
  20 +         Say Y here to enable support for EP93xx touch screen.
  21 +
  22 +         To compile this driver as a module, choose M here:
  23 +         the module will be called ep93xx_ts.
  24 +
  25  config TOUCHSCREEN_FUJITSU
  26         tristate "Fujitsu serial touchscreen"
  27         select SERIO
  28 --- a/drivers/input/touchscreen/Makefile
  29 +++ b/drivers/input/touchscreen/Makefile
  30 @@ -21,6 +21,7 @@ obj-$(CONFIG_TOUCHSCREEN_HAMPSHIRE)   += h
  31  obj-$(CONFIG_TOUCHSCREEN_GUNZE)                += gunze.o
  32  obj-$(CONFIG_TOUCHSCREEN_EETI)         += eeti_ts.o
  33  obj-$(CONFIG_TOUCHSCREEN_ELO)          += elo.o
  34 +obj-$(CONFIG_TOUCHSCREEN_EP93XX)       += ep93xx_ts.o
  35  obj-$(CONFIG_TOUCHSCREEN_FUJITSU)      += fujitsu_ts.o
  36  obj-$(CONFIG_TOUCHSCREEN_INEXIO)       += inexio.o
  37  obj-$(CONFIG_TOUCHSCREEN_MC13783)      += mc13783_ts.o
  38 --- /dev/null
  39 +++ b/drivers/input/touchscreen/ep93xx_ts.c
  40 @@ -0,0 +1,1020 @@
  41 +/*
  42 + * linux/drivers/input/touchscreen/ep93xx_ts.c
  43 + *
  44 + * Copyright (C) 2003-2004 Cirrus Corp.
  45 + *
  46 + * This program is free software; you can redistribute it and/or modify
  47 + * it under the terms of the GNU General Public License version 2 as
  48 + * published by the Free Software Foundation.
  49 + */
  50 +
  51 +#include <linux/module.h>
  52 +#include <linux/types.h>
  53 +#include <linux/delay.h>
  54 +#include <linux/wait.h>
  55 +#include <linux/fs.h>
  56 +#include <linux/sched.h>
  57 +#include <linux/poll.h>
  58 +#include <linux/miscdevice.h>
  59 +#include <linux/init.h>
  60 +#include <linux/compiler.h>
  61 +#include <linux/timer.h>
  62 +#include <linux/interrupt.h>
  63 +#include <linux/syscalls.h>
  64 +#include <linux/input.h>
  65 +#include <asm/irq.h>
  66 +#include <mach/hardware.h>
  67 +#include <asm/io.h>
  68 +
  69 +/* This stuff should be in ep93xx-regs.h */
  70 +#define EP93XX_TOUCHSCREEN_REG(x)      (EP93XX_TOUCHSCREEN_BASE + (x))
  71 +/* R/W touchscreen controller setup control register. */
  72 +#define EP93XX_TOUCHSCREEN_SETUP       EP93XX_TOUCHSCREEN_REG(0x00)
  73 +/* R/W touchscreen controller max/min register. */
  74 +#define EP93XX_TOUCHSCREEN_XYMAXMIN    EP93XX_TOUCHSCREEN_REG(0x04)
  75 +/* R   touchscreen controller result register. */
  76 +#define EP93XX_TOUCHSCREEN_XYRESULT    EP93XX_TOUCHSCREEN_REG(0x08)
  77 +/* LOCKED R/W touchscreen Switch Matrix control register. */
  78 +#define EP93XX_TOUCHSCREEN_DISCHARGE   EP93XX_TOUCHSCREEN_REG(0x0C)
  79 +#define EP93XX_TOUCHSCREEN_XSAMPLE     EP93XX_TOUCHSCREEN_REG(0x10)
  80 +#define EP93XX_TOUCHSCREEN_YSAMPLE     EP93XX_TOUCHSCREEN_REG(0x14)
  81 +#define EP93XX_TOUCHSCREEN_DIRECT      EP93XX_TOUCHSCREEN_REG(0x18)
  82 +#define EP93XX_TOUCHSCREEN_DETECT      EP93XX_TOUCHSCREEN_REG(0x1C)
  83 +/*  NA    R/W touchscreen software lock register. */
  84 +#define EP93XX_TOUCHSCREEN_SWLOCK      EP93XX_TOUCHSCREEN_REG(0x20)
  85 +/* R/W touchscreen setup control register #2. */
  86 +#define EP93XX_TOUCHSCREEN_SETUP2      EP93XX_TOUCHSCREEN_REG(0x24)
  87 +
  88 +/* These are duplicated in mach-ep93xx/core.c */
  89 +#define EP93XX_TIMER_REG(x)    (EP93XX_TIMER_BASE + (x))
  90 +#define EP93XX_TIMER2_LOAD     EP93XX_TIMER_REG(0x20)
  91 +#define EP93XX_TIMER2_VALUE    EP93XX_TIMER_REG(0x24)
  92 +#define EP93XX_TIMER2_CONTROL  EP93XX_TIMER_REG(0x28)
  93 +#define EP93XX_TIMER2_CLEAR    EP93XX_TIMER_REG(0x2c)
  94 +
  95 +/*
  96 + * Register bit definitions
  97 + */
  98 +#define TSSETUP_SDLY_MASK      0x000003FF
  99 +#define TSSETUP_SDLY_SHIFT     0
 100 +#define TSSETUP_NSMP_4         0x00000000
 101 +#define TSSETUP_NSMP_8         0x00000400
 102 +#define TSSETUP_NSMP_16                0x00000800
 103 +#define TSSETUP_NSMP_32                0x00000C00
 104 +#define TSSETUP_NSMP_MASK      0x00000C00
 105 +#define TSSETUP_DEV_4          0x00000000
 106 +#define TSSETUP_DEV_8          0x00001000
 107 +#define TSSETUP_DEV_12         0x00002000
 108 +#define TSSETUP_DEV_16         0x00003000
 109 +#define TSSETUP_DEV_24         0x00004000
 110 +#define TSSETUP_DEV_32         0x00005000
 111 +#define TSSETUP_DEV_64         0x00006000
 112 +#define TSSETUP_DEV_128                0x00007000
 113 +#define TSSETUP_ENABLE         0x00008000
 114 +#define TSSETUP_DLY_MASK       0x03FF0000
 115 +#define TSSETUP_DLY_SHIFT      16
 116 +#define TSSETUP_TDTCT          0x80000000
 117 +
 118 +#define TSMAXMIN_XMIN_MASK     0x000000FF
 119 +#define TSMAXMIN_XMIN_SHIFT    0
 120 +#define TSMAXMIN_YMIN_MASK     0x0000FF00
 121 +#define TSMAXMIN_YMIN_SHIFT    8
 122 +#define TSMAXMIN_XMAX_MASK     0x00FF0000
 123 +#define TSMAXMIN_XMAX_SHIFT    16
 124 +#define TSMAXMIN_YMAX_MASK     0xFF000000
 125 +#define TSMAXMIN_YMAX_SHIFT    24
 126 +
 127 +#define TSXYRESULT_X_MASK      0x00000FFF
 128 +#define TSXYRESULT_X_SHIFT     0
 129 +#define TSXYRESULT_AD_MASK     0x0000FFFF
 130 +#define TSXYRESULT_AD_SHIFT    0
 131 +#define TSXYRESULT_Y_MASK      0x0FFF0000
 132 +#define TSXYRESULT_Y_SHIFT     16
 133 +#define TSXYRESULT_SDR         0x80000000
 134 +
 135 +#define TSX_SAMPLE_MASK                0x00003FFF
 136 +#define TSX_SAMPLE_SHIFT       0x00
 137 +#define TSY_SAMPLE_MASK                0x3FFF0000
 138 +#define TSY_SAMPLE_SHIFT       0x10
 139 +
 140 +#define TSSETUP2_TINT          0x00000001
 141 +#define TSSETUP2_NICOR         0x00000002
 142 +#define TSSETUP2_PINT          0x00000004
 143 +#define TSSETUP2_PENSTS                0x00000008
 144 +#define TSSETUP2_PINTEN                0x00000010
 145 +#define TSSETUP2_DEVINT                0x00000020
 146 +#define TSSETUP2_DINTEN                0x00000040
 147 +#define TSSETUP2_DTMEN         0x00000080
 148 +#define TSSETUP2_DISDEV                0x00000100
 149 +#define TSSETUP2_NSIGND                0x00000200
 150 +#define TSSETUP2_S28EN         0x00000400
 151 +#define TSSETUP2_RINTEN                0x00000800
 152 +
 153 +#define TSXYRESULT_SDR         0x80000000
 154 +
 155 +/*
 156 + * These are used as trigger levels to know when we have pen up/down.
 157 + * The rules:
 158 + * 1.  TS_HEAVY_INV_PRESSURE < TS_LIGHT_INV_PRESSURE because these
 159 + *    are Inverse pressure.
 160 + * 2.  Any touch lighter than TS_LIGHT_INV_PRESSURE is a pen up.
 161 + * 3.  Any touch heavier than TS_HEAVY_INV_PRESSURE is a pen down.
 162 + */
 163 +#define TS_HEAVY_INV_PRESSURE 0xFE0 /* C00 */
 164 +#define TS_LIGHT_INV_PRESSURE 0xFFF /* e00 */
 165 +
 166 +/*
 167 + * If the x, y, or inverse pressure changes more than these values
 168 + * between two succeeding points, the point is not reported.
 169 + */
 170 +#define TS_MAX_VALID_XY_CHANGE         0x300
 171 +#define TS_MAX_VALID_PRESSURE_CHANGE   0x100
 172 +
 173 +/*
 174 + * This is the minimum Z1 Value that is valid.
 175 + */
 176 +#define MIN_Z1_VALUE 0x50
 177 +
 178 +/*
 179 + * Settling delay for taking each ADC measurement.  Increase this
 180 + * if ts is jittery.
 181 + */
 182 +#define EP93XX_TS_ADC_DELAY_USEC 2000
 183 +
 184 +/*
 185 + * Delay between TS points.
 186 + */
 187 +#define EP93XX_TS_PER_POINT_DELAY_USEC 10000
 188 +
 189 +/*
 190 + * A few more macros...
 191 + */
 192 +#define TSSETUP_DEFAULT  (TSSETUP_NSMP_32 | TSSETUP_DEV_64 |  \
 193 +                         ((128<<TSSETUP_SDLY_SHIFT) & TSSETUP_SDLY_MASK) | \
 194 +                         ((128<<TSSETUP_DLY_SHIFT)  & TSSETUP_DLY_MASK))
 195 +
 196 +#define TSSETUP2_DEFAULT (TSSETUP2_NSIGND)
 197 +
 198 +/*
 199 + * For now, we use one of the minor numbers from the local/experimental
 200 + * range.
 201 + */
 202 +#define EP93XX_TS_MINOR 240
 203 +
 204 +/*
 205 + * Static Declarations
 206 + */
 207 +static unsigned int   guiLastX, guiLastY;
 208 +static unsigned int   guiLastInvPressure;
 209 +
 210 +struct TouchScreenSample
 211 +{
 212 +    int currentX;
 213 +    int currentY;
 214 +    int currentButton;
 215 +    int currentPressure;
 216 +    struct timeval currentTime;
 217 +};
 218 +
 219 +/*
 220 + * This must match the structure in tslib.
 221 + */
 222 +struct ts_sample {
 223 +    int x;
 224 +    int y;
 225 +    unsigned int pressure;
 226 +    struct timeval tv;
 227 +};
 228 +
 229 +static struct TouchScreenSample gSample;
 230 +static int bFreshTouchData;
 231 +static int bCurrentPenDown;
 232 +
 233 +static DECLARE_WAIT_QUEUE_HEAD(queue);
 234 +static DECLARE_MUTEX(open_sem);
 235 +static spinlock_t event_buffer_lock = SPIN_LOCK_UNLOCKED;
 236 +static struct fasync_struct *ep93xx_fasync;
 237 +
 238 +/*
 239 + * Typedef Declarations
 240 + */
 241 +typedef enum {
 242 +    TS_MODE_UN_INITIALIZED,
 243 +    TS_MODE_HARDWARE_SCAN,
 244 +    TS_MODE_SOFT_SCAN
 245 +} ts_mode_t;
 246 +
 247 +static ts_mode_t gScanningMode;
 248 +
 249 +typedef enum{
 250 +    TS_STATE_STOPPED = 0,
 251 +    TS_STATE_Z1,
 252 +    TS_STATE_Z2,
 253 +    TS_STATE_Y,
 254 +    TS_STATE_X,
 255 +    TS_STATE_DONE
 256 +} ts_states_t;
 257 +
 258 +typedef struct
 259 +{
 260 +    unsigned int uiX;
 261 +    unsigned int uiY;
 262 +    unsigned int uiZ1;
 263 +    unsigned int uiZ2;
 264 +    ts_states_t  state;
 265 +} ts_struct_t;
 266 +
 267 +static ts_struct_t sTouch;
 268 +
 269 +/*
 270 + * From the spec, here's how to set up the touch screen's switch registers.
 271 + */
 272 +typedef struct
 273 +{
 274 +    unsigned int uiDetect;
 275 +    unsigned int uiDischarge;
 276 +    unsigned int uiXSample;
 277 +    unsigned int uiYSample;
 278 +    unsigned int uiSwitchZ1;
 279 +    unsigned int uiSwitchZ2;
 280 +}SwitchStructType;
 281 +
 282 +/*
 283 + * Here's the switch settings for a 4-wire touchscreen.  See the spec
 284 + * for how to handle a 4, 7, or 8-wire.
 285 + */
 286 +const static SwitchStructType sSwitchSettings =
 287 +/* s28en=0 */
 288 +/*   TSDetect    TSDischarge TSXSample   TSYSample   SwitchZ1    SwitchZ2 */
 289 +    {0x00403604, 0x0007fe04, 0x00081604, 0x00104601, 0x00101601, 0x00101608};
 290 +
 291 +/*
 292 + * Function declarations
 293 + */
 294 +static void ep93xx_ts_set_direct(unsigned int uiADCSwitch);
 295 +static irqreturn_t ep93xx_ts_isr(int irq, void *dev_id);
 296 +static irqreturn_t ep93xx_timer2_isr(int irq, void *dev_id);
 297 +static void ee93xx_ts_evt_add(int button, int dX, int dY, int Pressure);
 298 +static ssize_t ep93xx_ts_read(struct file *filp, char *buf,
 299 +       size_t count, loff_t *l);
 300 +static unsigned int ep93xx_ts_poll(struct file *filp, poll_table *wait);
 301 +static int ep93xx_ts_open(struct inode *inode, struct file *filp);
 302 +static int ep93xx_ts_fasync(int fd, struct file *filp, int on);
 303 +static int ep93xx_ts_release(struct inode *inode, struct file *filp);
 304 +static ssize_t ep93xx_ts_write(struct file *file, const char *buffer,
 305 +               size_t count, loff_t *ppos);
 306 +static void ep93xx_ts_setup(void);
 307 +static void ep93xx_ts_shutdown(void);
 308 +int __init ep93xx_ts_init(void);
 309 +void __exit ep93xx_ts_exit(void);
 310 +static unsigned int CalculateInvPressure(void);
 311 +static unsigned int ADCGetData(unsigned int uiSamples, unsigned int uiMaxDiff);
 312 +static void TS_Soft_Scan_Mode(void);
 313 +static void TS_Hardware_Scan_Mode(void);
 314 +static void ProcessPointData(void);
 315 +static void Set_Timer2_uSec(unsigned int Delay_mSec);
 316 +static void Stop_Timer2(void);
 317 +
 318 +/*
 319 + *  ep93xx_ts_isr
 320 + */
 321 +static irqreturn_t ep93xx_ts_isr(int irq, void *dev_id)
 322 +{
 323 +    /*
 324 +     * Note that we don't clear the interrupt here.  The interrupt
 325 +     * gets cleared in TS_Soft_Scan_Mode when the TS ENABLE
 326 +     * bit is cleared.
 327 +     */
 328 +
 329 +    /*
 330 +     * Set the ts to manual polling mode and schedule a callback.
 331 +     * That way we can return from the isr in a reasonable amount of
 332 +     * time and process the touch in the callback after a brief delay.
 333 +     */
 334 +    TS_Soft_Scan_Mode();
 335 +
 336 +    return(IRQ_HANDLED);
 337 +}
 338 +
 339 +/*
 340 + * Save the current ts 'event' in an atomic fashion.
 341 + */
 342 +static void ee93xx_ts_evt_add(int buttons, int iX, int iY, int iPressure)
 343 +{
 344 +    /*
 345 +     * Note the event, but use spinlocks to keep it from getting
 346 +     * halfway read if we get interrupted.
 347 +     */
 348 +
 349 +    spin_lock(&event_buffer_lock);
 350 +
 351 +    gSample.currentX        = iX;
 352 +    gSample.currentY        = iY;
 353 +    gSample.currentButton   = buttons;
 354 +    gSample.currentPressure = iPressure;
 355 +    bFreshTouchData         = 1;
 356 +    do_gettimeofday(&gSample.currentTime);
 357 +
 358 +    spin_unlock(&event_buffer_lock);
 359 +
 360 +    kill_fasync(&ep93xx_fasync, SIGIO, POLL_IN);
 361 +    wake_up_interruptible(&queue);
 362 +}
 363 +
 364 +
 365 +static ssize_t ep93xx_ts_read(struct file *filp, char *buf, size_t count, loff_t *l)
 366 +{
 367 +    unsigned short data[3];
 368 +    struct  ts_sample   ts_data;
 369 +    int     iReturn = -EFAULT;
 370 +
 371 +    if (!bFreshTouchData)
 372 +    {
 373 +       iReturn = 0;
 374 +    }
 375 +    else if (count == sizeof(data))
 376 +    {
 377 +       spin_lock_irq(&event_buffer_lock);
 378 +       bFreshTouchData = 0;
 379 +       data[0] = gSample.currentX;
 380 +       data[1] = gSample.currentY;
 381 +       data[2] = gSample.currentButton;
 382 +
 383 +       spin_unlock_irq(&event_buffer_lock);
 384 +
 385 +       if (copy_to_user(buf, data, sizeof data))
 386 +           return -EFAULT;
 387 +
 388 +       count -= sizeof(data);
 389 +
 390 +       /* return the # of bytes that got read */
 391 +       iReturn = sizeof(data) ;
 392 +    }
 393 +    else if (count == sizeof(struct ts_sample) )
 394 +    {
 395 +       spin_lock_irq(&event_buffer_lock);
 396 +       bFreshTouchData = 0;
 397 +       ts_data.x           = gSample.currentX;
 398 +       ts_data.y           = gSample.currentY;
 399 +       ts_data.pressure    = gSample.currentPressure;
 400 +       ts_data.tv          = gSample.currentTime;
 401 +       spin_unlock_irq(&event_buffer_lock);
 402 +
 403 +       if (copy_to_user(buf, &ts_data, sizeof(struct ts_sample)))
 404 +       {
 405 +           iReturn = -EFAULT;
 406 +       }
 407 +       else
 408 +       {
 409 +           count -= sizeof(ts_data);
 410 +           iReturn = sizeof(ts_data);
 411 +       }
 412 +    }
 413 +
 414 +    return iReturn;
 415 +}
 416 +
 417 +static unsigned int ep93xx_ts_poll(struct file *filp, poll_table *wait)
 418 +{
 419 +    poll_wait(filp, &queue, wait);
 420 +
 421 +    if (bFreshTouchData)
 422 +    {
 423 +       return POLLIN | POLLRDNORM;
 424 +    }
 425 +
 426 +    return 0;
 427 +}
 428 +
 429 +static int ep93xx_ts_open(struct inode *inode, struct file *filp)
 430 +{
 431 +    if (down_trylock(&open_sem))
 432 +    {
 433 +       return -EBUSY;
 434 +    }
 435 +
 436 +    ep93xx_ts_setup();
 437 +
 438 +    return 0;
 439 +}
 440 +
 441 +/*
 442 + * Asynchronous I/O support.
 443 + */
 444 +static int ep93xx_ts_fasync(int fd, struct file *filp, int on)
 445 +{
 446 +    int retval;
 447 +
 448 +    retval = fasync_helper(fd, filp, on, &ep93xx_fasync);
 449 +    if (retval < 0)
 450 +    {
 451 +       return retval;
 452 +    }
 453 +
 454 +    return 0;
 455 +}
 456 +
 457 +static int ep93xx_ts_release(struct inode *inode, struct file *filp)
 458 +{
 459 +    Stop_Timer2();
 460 +
 461 +    /*
 462 +     * Call our async I/O support to request that this file
 463 +     * cease to be used for async I/O.
 464 +     */
 465 +    ep93xx_ts_fasync(-1, filp, 0);
 466 +
 467 +    ep93xx_ts_shutdown();
 468 +
 469 +    up(&open_sem);
 470 +
 471 +    return 0;
 472 +}
 473 +
 474 +static ssize_t ep93xx_ts_write(struct file *file, const char *buffer, size_t count,
 475 +              loff_t *ppos)
 476 +{
 477 +    return -EINVAL;
 478 +}
 479 +
 480 +
 481 +static int ep93xx_ts_ioctl(struct inode *inode, struct file *file, uint command, ulong u)
 482 +{
 483 +    static const int         version = EV_VERSION;
 484 +    static const u_int32_t   bit =(1 << EV_ABS);
 485 +    static const u_int32_t   absbit = (1 << ABS_X) | (1 << ABS_Y) | (1 << ABS_PRESSURE);
 486 +    int         iReturn ;
 487 +    int         i = 0;
 488 +
 489 +    switch(command)
 490 +    {
 491 +       case EVIOCGVERSION:
 492 +           i = copy_to_user((void __user *)u, (void *)version, sizeof(version));
 493 +           iReturn = i ? -EFAULT : 0;
 494 +           break;
 495 +
 496 +       case EVIOCGBIT(0,sizeof(u_int32_t) * 8) :
 497 +           i = copy_to_user((void __user *)u, (void *)bit, sizeof(bit));
 498 +           iReturn = i ? -EFAULT : 0;
 499 +           break;
 500 +
 501 +       case EVIOCGBIT(EV_ABS, sizeof(absbit) * 8):
 502 +           i = copy_to_user((void __user *)u, (void *)absbit, sizeof(absbit));
 503 +           iReturn = i ? -EFAULT : 0;
 504 +           break;
 505 +       default:
 506 +           iReturn = -1;
 507 +           break;
 508 +    }
 509 +
 510 +    return iReturn;
 511 +}
 512 +
 513 +static struct file_operations ep93xx_ts_fops = {
 514 +    owner:      THIS_MODULE,
 515 +    read:       ep93xx_ts_read,
 516 +    write:      ep93xx_ts_write,
 517 +    poll:       ep93xx_ts_poll,
 518 +    open:       ep93xx_ts_open,
 519 +    unlocked_ioctl:      ep93xx_ts_ioctl,
 520 +    release:    ep93xx_ts_release,
 521 +    fasync:     ep93xx_ts_fasync,
 522 +};
 523 +
 524 +static struct miscdevice ep93xx_ts_miscdev =
 525 +{
 526 +       EP93XX_TS_MINOR,
 527 +       "ep93xx_ts",
 528 +       &ep93xx_ts_fops
 529 +};
 530 +
 531 +void ep93xx_ts_setup(void)
 532 +{
 533 +    unsigned int uiKTDIV, uiTSXYMaxMin;
 534 +
 535 +    /*
 536 +     * Set the TSEN bit in KTDIV so that we are enabling the clock
 537 +     * for the touchscreen.
 538 +     */
 539 +    uiKTDIV = __raw_readl(EP93XX_SYSCON_KEYTCHCLKDIV);
 540 +    uiKTDIV |= EP93XX_SYSCON_KEYTCHCLKDIV_TSEN;
 541 +    ep93xx_syscon_swlocked_write(uiKTDIV, EP93XX_SYSCON_KEYTCHCLKDIV);
 542 +
 543 +    /*
 544 +     * Program the EP93XX_TOUCHSCREEN_SETUP and TSSetup2 registers.
 545 +     */
 546 +    __raw_writel(TSSETUP_DEFAULT, EP93XX_TOUCHSCREEN_SETUP);
 547 +    __raw_writel(TSSETUP2_DEFAULT, EP93XX_TOUCHSCREEN_SETUP2);
 548 +
 549 +    /*
 550 +     * Set the the touch settings.
 551 +     */
 552 +    __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
 553 +    __raw_writel(sSwitchSettings.uiDischarge, EP93XX_TOUCHSCREEN_DIRECT);
 554 +
 555 +    __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
 556 +    __raw_writel(sSwitchSettings.uiDischarge, EP93XX_TOUCHSCREEN_DISCHARGE);
 557 +
 558 +    __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
 559 +    __raw_writel(sSwitchSettings.uiSwitchZ1, EP93XX_TOUCHSCREEN_XSAMPLE);
 560 +
 561 +    __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
 562 +    __raw_writel(sSwitchSettings.uiSwitchZ2, EP93XX_TOUCHSCREEN_YSAMPLE);
 563 +
 564 +    __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
 565 +    __raw_writel(sSwitchSettings.uiDetect, EP93XX_TOUCHSCREEN_DETECT);
 566 +
 567 +    /*
 568 +     * X,YMin set to 0x40 = have to drag that many pixels for a new irq.
 569 +     * X,YMax set to 0x40 = 1024 pixels is the maximum movement within the
 570 +     * time scan limit.
 571 +     */
 572 +    uiTSXYMaxMin =  (50   << TSMAXMIN_XMIN_SHIFT) & TSMAXMIN_XMIN_MASK;
 573 +    uiTSXYMaxMin |= (50   << TSMAXMIN_YMIN_SHIFT) & TSMAXMIN_YMIN_MASK;
 574 +    uiTSXYMaxMin |= (0xff << TSMAXMIN_XMAX_SHIFT) & TSMAXMIN_XMAX_MASK;
 575 +    uiTSXYMaxMin |= (0xff << TSMAXMIN_YMAX_SHIFT) & TSMAXMIN_YMAX_MASK;
 576 +    __raw_writel(uiTSXYMaxMin, EP93XX_TOUCHSCREEN_XYMAXMIN);
 577 +
 578 +    bCurrentPenDown = 0;
 579 +    bFreshTouchData = 0;
 580 +    guiLastX = 0;
 581 +    guiLastY = 0;
 582 +    guiLastInvPressure = 0xffffff;
 583 +
 584 +    /*
 585 +     * Enable the touch screen scanning engine.
 586 +     */
 587 +    TS_Hardware_Scan_Mode();
 588 +}
 589 +
 590 +/*
 591 + * ep93xx_ts_shutdown
 592 + *
 593 + */
 594 +static void
 595 +ep93xx_ts_shutdown(void)
 596 +{
 597 +    unsigned int uiKTDIV;
 598 +
 599 +    sTouch.state = TS_STATE_STOPPED;
 600 +    Stop_Timer2();
 601 +
 602 +    /*
 603 +     * Disable the scanning engine.
 604 +     */
 605 +    __raw_writel(0, EP93XX_TOUCHSCREEN_SETUP);
 606 +    __raw_writel(0, EP93XX_TOUCHSCREEN_SETUP2);
 607 +
 608 +    /*
 609 +     * Clear the TSEN bit in KTDIV so that we are disabling the clock
 610 +     * for the touchscreen.
 611 +     */
 612 +    uiKTDIV = __raw_readl(EP93XX_SYSCON_KEYTCHCLKDIV);
 613 +    uiKTDIV &= ~EP93XX_SYSCON_KEYTCHCLKDIV_TSEN;
 614 +    ep93xx_syscon_swlocked_write(uiKTDIV, EP93XX_SYSCON_KEYTCHCLKDIV);
 615 +
 616 +} /* ep93xx_ts_shutdown */
 617 +
 618 +static irqreturn_t ep93xx_timer2_isr(int irq, void *dev_id)
 619 +{
 620 +    switch(sTouch.state)
 621 +    {
 622 +       case TS_STATE_STOPPED:
 623 +           TS_Hardware_Scan_Mode();
 624 +           break;
 625 +
 626 +       /*
 627 +        * Get the Z1 value for pressure measurement and set up
 628 +        * the switch register for getting the Z2 measurement.
 629 +        */
 630 +       case TS_STATE_Z1:
 631 +           Set_Timer2_uSec(EP93XX_TS_ADC_DELAY_USEC);
 632 +           sTouch.uiZ1 = ADCGetData(2, 200);
 633 +           ep93xx_ts_set_direct(sSwitchSettings.uiSwitchZ2);
 634 +           sTouch.state = TS_STATE_Z2;
 635 +           break;
 636 +
 637 +       /*
 638 +        * Get the Z2 value for pressure measurement and set up
 639 +        * the switch register for getting the Y measurement.
 640 +        */
 641 +       case TS_STATE_Z2:
 642 +           sTouch.uiZ2 = ADCGetData(2, 200);
 643 +           ep93xx_ts_set_direct(sSwitchSettings.uiYSample);
 644 +           sTouch.state = TS_STATE_Y;
 645 +           break;
 646 +
 647 +       /*
 648 +        * Get the Y value and set up the switch register for
 649 +        * getting the X measurement.
 650 +        */
 651 +       case TS_STATE_Y:
 652 +           sTouch.uiY = ADCGetData(4, 20);
 653 +           ep93xx_ts_set_direct(sSwitchSettings.uiXSample);
 654 +           sTouch.state = TS_STATE_X;
 655 +           break;
 656 +
 657 +       /*
 658 +        * Read the X value.  This is the last of the 4 adc values
 659 +        * we need so we continue on to process the data.
 660 +        */
 661 +       case TS_STATE_X:
 662 +           Stop_Timer2();
 663 +
 664 +           sTouch.uiX = ADCGetData(4, 20);
 665 +
 666 +           __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
 667 +           __raw_writel(sSwitchSettings.uiDischarge, EP93XX_TOUCHSCREEN_DIRECT);
 668 +
 669 +           sTouch.state = TS_STATE_DONE;
 670 +
 671 +           /*
 672 +            * Process this set of ADC readings.
 673 +            */
 674 +           ProcessPointData();
 675 +
 676 +           break;
 677 +
 678 +       /*
 679 +        * Shouldn't get here.  But if we do, we can recover...
 680 +        */
 681 +       case TS_STATE_DONE:
 682 +           TS_Hardware_Scan_Mode();
 683 +           break;
 684 +    }
 685 +
 686 +    /*
 687 +     * Clear the timer2 interrupt.
 688 +     */
 689 +    __raw_writel(1, EP93XX_TIMER2_CLEAR);
 690 +    return(IRQ_HANDLED);
 691 +}
 692 +
 693 +/*---------------------------------------------------------------------
 694 + * ProcessPointData
 695 + *
 696 + * This routine processes the ADC data into usable point data and then
 697 + * puts the driver into hw or sw scanning mode before returning.
 698 + *
 699 + * We calculate inverse pressure (lower number = more pressure) then
 700 + * do a hystheresis with the two pressure values 'light' and 'heavy'.
 701 + *
 702 + * If we are above the light, we have pen up.
 703 + * If we are below the heavy we have pen down.
 704 + * As long as the pressure stays below the light, pen stays down.
 705 + * When we get above the light again, pen goes back up.
 706 + *
 707 + */
 708 +static void ProcessPointData(void)
 709 +{
 710 +    int  bValidPoint = 0;
 711 +    unsigned int   uiXDiff, uiYDiff, uiInvPressureDiff;
 712 +    unsigned int   uiInvPressure;
 713 +
 714 +    /*
 715 +     * Calculate the current pressure.
 716 +     */
 717 +    uiInvPressure = CalculateInvPressure();
 718 +
 719 +    /*
 720 +     * If pen pressure is so light that it is greater than the 'max' setting
 721 +     * then we consider this to be a pen up.
 722 +     */
 723 +    if (uiInvPressure >= TS_LIGHT_INV_PRESSURE)
 724 +    {
 725 +       bCurrentPenDown = 0;
 726 +       ee93xx_ts_evt_add(0, guiLastX, guiLastY, 0);
 727 +       TS_Hardware_Scan_Mode();
 728 +       return;
 729 +    }
 730 +
 731 +    /*
 732 +     * Hysteresis:
 733 +     * If the pen pressure is hard enough to be less than the 'min' OR
 734 +     * the pen is already down and is still less than the 'max'...
 735 +     */
 736 +    if ((uiInvPressure < TS_HEAVY_INV_PRESSURE) ||
 737 +       (bCurrentPenDown && (uiInvPressure < TS_LIGHT_INV_PRESSURE)))
 738 +    {
 739 +       if (bCurrentPenDown)
 740 +       {
 741 +           /*
 742 +            * If pen was previously down, check the difference between
 743 +            * the last sample and this one... if the difference between
 744 +            * samples is too great, ignore the sample.
 745 +            */
 746 +           uiXDiff = abs(guiLastX - sTouch.uiX);
 747 +           uiYDiff = abs(guiLastY - sTouch.uiY);
 748 +           uiInvPressureDiff = abs(guiLastInvPressure - uiInvPressure);
 749 +
 750 +           if (uiXDiff < TS_MAX_VALID_XY_CHANGE
 751 +               && uiYDiff < TS_MAX_VALID_XY_CHANGE
 752 +               && uiInvPressureDiff < TS_MAX_VALID_PRESSURE_CHANGE)
 753 +           {
 754 +               bValidPoint = 1;
 755 +           }
 756 +       }
 757 +       else
 758 +       {
 759 +           bValidPoint = 1;
 760 +       }
 761 +
 762 +       /*
 763 +        * If either the pen was put down or dragged make a note of it.
 764 +        */
 765 +       if (bValidPoint)
 766 +       {
 767 +           guiLastX = sTouch.uiX;
 768 +           guiLastY = sTouch.uiY;
 769 +           guiLastInvPressure = uiInvPressure;
 770 +           bCurrentPenDown = 1;
 771 +           ee93xx_ts_evt_add(1, sTouch.uiX, sTouch.uiY,
 772 +                             0x7000000 / uiInvPressure);
 773 +       }
 774 +
 775 +       TS_Soft_Scan_Mode();
 776 +       return;
 777 +    }
 778 +
 779 +    TS_Hardware_Scan_Mode();
 780 +}
 781 +
 782 +static void ep93xx_ts_set_direct(unsigned int uiADCSwitch)
 783 +{
 784 +    unsigned int uiResult;
 785 +
 786 +    /*
 787 +     * Set the switch settings in the direct register.
 788 +     */
 789 +    __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
 790 +    __raw_writel(uiADCSwitch, EP93XX_TOUCHSCREEN_DIRECT);
 791 +
 792 +    /*
 793 +     * Read and throw away the first sample.
 794 +     */
 795 +    do {
 796 +       uiResult = __raw_readl(EP93XX_TOUCHSCREEN_XYRESULT);
 797 +    } while (!(uiResult & TSXYRESULT_SDR));
 798 +
 799 +}
 800 +
 801 +static unsigned int ADCGetData(unsigned int uiSamples, unsigned int uiMaxDiff)
 802 +{
 803 +    unsigned int uiResult, uiValue, uiCount, uiLowest, uiHighest, uiSum, uiAve;
 804 +
 805 +    do
 806 +    {
 807 +       /*
 808 +        * Initialize our values.
 809 +        */
 810 +       uiLowest        = 0xfffffff;
 811 +       uiHighest       = 0;
 812 +       uiSum           = 0;
 813 +
 814 +       for (uiCount = 0; uiCount < uiSamples; uiCount++)
 815 +       {
 816 +           /*
 817 +            * Read the touch screen four more times and average.
 818 +            */
 819 +           do {
 820 +               uiResult = __raw_readl(EP93XX_TOUCHSCREEN_XYRESULT);
 821 +           } while (!(uiResult & TSXYRESULT_SDR));
 822 +
 823 +           uiValue = (uiResult & TSXYRESULT_AD_MASK) >> TSXYRESULT_AD_SHIFT;
 824 +           uiValue = ((uiValue >> 4) + ((1 + TSXYRESULT_X_MASK)>>1)) & TSXYRESULT_X_MASK;
 825 +
 826 +           /*
 827 +            * Add up the values.
 828 +            */
 829 +           uiSum += uiValue;
 830 +
 831 +           /*
 832 +            * Get the lowest and highest values.
 833 +            */
 834 +           if (uiValue < uiLowest)
 835 +           {
 836 +               uiLowest = uiValue;
 837 +           }
 838 +           if (uiValue > uiHighest)
 839 +           {
 840 +               uiHighest = uiValue;
 841 +           }
 842 +       }
 843 +    } while ((uiHighest - uiLowest) > uiMaxDiff);
 844 +
 845 +    /*
 846 +     * Calculate the Average value.
 847 +     */
 848 +    uiAve = uiSum / uiSamples;
 849 +
 850 +    return uiAve;
 851 +}
 852 +
 853 +/*
 854 + * CalculateInvPressure
 855 + *
 856 + * Is the Touch Valid.  Touch is not valid if the X or Y value is not
 857 + * in range and the pressure is not  enough.
 858 + *
 859 + * Touch resistance can be measured by the following formula:
 860 + *
 861 + *          Rx * X *     Z2
 862 + * Rtouch = --------- * (-- - 1)
 863 + *           4096        Z1
 864 + *
 865 + * This is simplified in the ration of Rtouch to Rx.  The lower the value, the
 866 + * higher the pressure.
 867 + *
 868 + *                     Z2
 869 + * InvPressure =  X * (-- - 1)
 870 + *                     Z1
 871 + */
 872 +static unsigned int CalculateInvPressure(void)
 873 +{
 874 +    unsigned int uiInvPressure;
 875 +
 876 +    /*
 877 +     * Check to see if the point is valid.
 878 +     */
 879 +    if (sTouch.uiZ1 < MIN_Z1_VALUE)
 880 +    {
 881 +       uiInvPressure = 0x10000;
 882 +    }
 883 +
 884 +    /*
 885 +     * Can omit the pressure calculation if you need to get rid of the division.
 886 +     */
 887 +    else
 888 +    {
 889 +       uiInvPressure = ((sTouch.uiX * sTouch.uiZ2) / sTouch.uiZ1) - sTouch.uiX;
 890 +    }
 891 +
 892 +    return uiInvPressure;
 893 +}
 894 +
 895 +/*
 896 + * TS_Hardware_Scan_Mode
 897 + *
 898 + * Enables the ep93xx ts scanning engine so that when the pen goes down
 899 + * we will get an interrupt.
 900 + */
 901 +static void TS_Hardware_Scan_Mode(void)
 902 +{
 903 +    unsigned int uiDevCfg;
 904 +
 905 +    /*
 906 +     * Disable the soft scanning engine.
 907 +     */
 908 +    sTouch.state = TS_STATE_STOPPED;
 909 +    Stop_Timer2();
 910 +
 911 +    /*
 912 +     * Clear the TIN (Touchscreen INactive) bit so we can go to
 913 +     * automatic scanning mode.
 914 +     */
 915 +    uiDevCfg = __raw_readl(EP93XX_SYSCON_DEVCFG);
 916 +    ep93xx_syscon_swlocked_write(uiDevCfg & ~EP93XX_SYSCON_DEVCFG_TIN,
 917 +                                EP93XX_SYSCON_DEVCFG);
 918 +
 919 +    /*
 920 +     * Enable the touch screen scanning state machine by setting
 921 +     * the ENABLE bit.
 922 +     */
 923 +    __raw_writel(TSSETUP_DEFAULT | TSSETUP_ENABLE, EP93XX_TOUCHSCREEN_SETUP);
 924 +
 925 +    /*
 926 +     * Set the flag to show that we are in interrupt mode.
 927 +     */
 928 +    gScanningMode = TS_MODE_HARDWARE_SCAN;
 929 +
 930 +    /*
 931 +     * Initialize EP93XX_TOUCHSCREEN_SETUP2 register.
 932 +     */
 933 +    __raw_writel(TSSETUP2_DEFAULT, EP93XX_TOUCHSCREEN_SETUP2);
 934 +
 935 +}
 936 +
 937 +/*
 938 + * TS_Soft_Scan_Mode
 939 + *
 940 + * Sets the touch screen to manual polling mode.
 941 + */
 942 +static void TS_Soft_Scan_Mode(void)
 943 +{
 944 +    unsigned int uiDevCfg;
 945 +
 946 +    if (gScanningMode != TS_MODE_SOFT_SCAN)
 947 +    {
 948 +       /*
 949 +        * Disable the touch screen scanning state machine by clearing
 950 +        * the ENABLE bit.
 951 +        */
 952 +       __raw_writel(TSSETUP_DEFAULT, EP93XX_TOUCHSCREEN_SETUP);
 953 +
 954 +       /*
 955 +        * Set the TIN bit so we can do manual touchscreen polling.
 956 +        */
 957 +       uiDevCfg = __raw_readl(EP93XX_SYSCON_DEVCFG);
 958 +       ep93xx_syscon_swlocked_write(uiDevCfg | EP93XX_SYSCON_DEVCFG_TIN,
 959 +                                    EP93XX_SYSCON_DEVCFG);
 960 +    }
 961 +
 962 +    /*
 963 +     * Set the switch register up for the first ADC reading
 964 +     */
 965 +    ep93xx_ts_set_direct(sSwitchSettings.uiSwitchZ1);
 966 +
 967 +    /*
 968 +     * Initialize our software state machine to know which ADC
 969 +     * reading to take
 970 +     */
 971 +    sTouch.state = TS_STATE_Z1;
 972 +
 973 +    /*
 974 +     * Set the timer so after a mSec or two settling delay it will
 975 +     * take the first ADC reading.
 976 +     */
 977 +    Set_Timer2_uSec(EP93XX_TS_PER_POINT_DELAY_USEC);
 978 +
 979 +    /*
 980 +     * Note that we are in sw scanning mode not hw scanning mode.
 981 +     */
 982 +    gScanningMode = TS_MODE_SOFT_SCAN;
 983 +
 984 +}
 985 +
 986 +static void Set_Timer2_uSec(unsigned int uiDelay_uSec)
 987 +{
 988 +    unsigned int uiClockTicks;
 989 +
 990 +    /*
 991 +     * Stop timer 2
 992 +     */
 993 +    __raw_writel(0, EP93XX_TIMER2_CONTROL);
 994 +
 995 +    uiClockTicks = ((uiDelay_uSec * 508) + 999) / 1000;
 996 +    __raw_writel(uiClockTicks, EP93XX_TIMER2_LOAD);
 997 +    __raw_writel(uiClockTicks, EP93XX_TIMER2_VALUE);
 998 +
 999 +    /*
1000 +     * Set up Timer 2 for 508 kHz clock and periodic mode.
1001 +     */
1002 +    __raw_writel(0xC8, EP93XX_TIMER2_CONTROL);
1003 +
1004 +}
1005 +
1006 +static void Stop_Timer2(void)
1007 +{
1008 +    __raw_writel(0, EP93XX_TIMER2_CONTROL);
1009 +}
1010 +
1011 +/*
1012 + * Initialization and exit routines
1013 + */
1014 +int __init ep93xx_ts_init(void)
1015 +{
1016 +    int retval;
1017 +
1018 +    retval = request_irq(IRQ_EP93XX_TOUCH, ep93xx_ts_isr,
1019 +                        IRQF_DISABLED, "ep93xx_ts", 0);
1020 +    if (retval)
1021 +    {
1022 +       printk(KERN_WARNING "ep93xx_ts: failed to get touchscreen IRQ\n");
1023 +       return retval;
1024 +    }
1025 +
1026 +    retval = request_irq(IRQ_EP93XX_TIMER2, ep93xx_timer2_isr,
1027 +                        IRQF_DISABLED, "ep93xx_timer2", 0);
1028 +    if (retval)
1029 +    {
1030 +       printk(KERN_WARNING "ep93xx_ts: failed to get timer2 IRQ\n");
1031 +       free_irq(IRQ_EP93XX_TOUCH, 0);
1032 +       return retval;
1033 +    }
1034 +
1035 +    misc_register(&ep93xx_ts_miscdev);
1036 +
1037 +    sTouch.state = TS_STATE_STOPPED;
1038 +    gScanningMode = TS_MODE_UN_INITIALIZED;
1039 +
1040 +    printk(KERN_NOTICE "ep93xx touchscreen driver configured for 4-wire operation\n");
1041 +
1042 +    return 0;
1043 +}
1044 +
1045 +void __exit ep93xx_ts_exit(void)
1046 +{
1047 +    Stop_Timer2();
1048 +
1049 +    free_irq(IRQ_EP93XX_TOUCH, 0);
1050 +    free_irq(IRQ_EP93XX_TIMER2, 0);
1051 +
1052 +    misc_deregister(&ep93xx_ts_miscdev);
1053 +}
1054 +
1055 +module_init(ep93xx_ts_init);
1056 +module_exit(ep93xx_ts_exit);
1057 +
1058 +MODULE_DESCRIPTION("Cirrus EP93xx touchscreen driver");
1059 +MODULE_SUPPORTED_DEVICE("touchscreen/ep93xx");
1060 +MODULE_LICENSE("GPL");