target/linux/ep93xx/patches-3.2/003-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 @@ -177,6 +177,15 @@ 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 @@ -23,6 +23,7 @@ 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_INTEL_MID)    += intel-mid-touch.o
  38 --- /dev/null
  39 +++ b/drivers/input/touchscreen/ep93xx_ts.c
  40 @@ -0,0 +1,1021 @@
  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 <linux/semaphore.h>
  66 +#include <asm/irq.h>
  67 +#include <mach/hardware.h>
  68 +#include <asm/io.h>
  69 +
  70 +/* This stuff should be in ep93xx-regs.h */
  71 +#define EP93XX_TOUCHSCREEN_REG(x)      (EP93XX_TOUCHSCREEN_BASE + (x))
  72 +/* R/W touchscreen controller setup control register. */
  73 +#define EP93XX_TOUCHSCREEN_SETUP       EP93XX_TOUCHSCREEN_REG(0x00)
  74 +/* R/W touchscreen controller max/min register. */
  75 +#define EP93XX_TOUCHSCREEN_XYMAXMIN    EP93XX_TOUCHSCREEN_REG(0x04)
  76 +/* R   touchscreen controller result register. */
  77 +#define EP93XX_TOUCHSCREEN_XYRESULT    EP93XX_TOUCHSCREEN_REG(0x08)
  78 +/* LOCKED R/W touchscreen Switch Matrix control register. */
  79 +#define EP93XX_TOUCHSCREEN_DISCHARGE   EP93XX_TOUCHSCREEN_REG(0x0C)
  80 +#define EP93XX_TOUCHSCREEN_XSAMPLE     EP93XX_TOUCHSCREEN_REG(0x10)
  81 +#define EP93XX_TOUCHSCREEN_YSAMPLE     EP93XX_TOUCHSCREEN_REG(0x14)
  82 +#define EP93XX_TOUCHSCREEN_DIRECT      EP93XX_TOUCHSCREEN_REG(0x18)
  83 +#define EP93XX_TOUCHSCREEN_DETECT      EP93XX_TOUCHSCREEN_REG(0x1C)
  84 +/*  NA    R/W touchscreen software lock register. */
  85 +#define EP93XX_TOUCHSCREEN_SWLOCK      EP93XX_TOUCHSCREEN_REG(0x20)
  86 +/* R/W touchscreen setup control register #2. */
  87 +#define EP93XX_TOUCHSCREEN_SETUP2      EP93XX_TOUCHSCREEN_REG(0x24)
  88 +
  89 +/* These are duplicated in mach-ep93xx/core.c */
  90 +#define EP93XX_TIMER_REG(x)    (EP93XX_TIMER_BASE + (x))
  91 +#define EP93XX_TIMER2_LOAD     EP93XX_TIMER_REG(0x20)
  92 +#define EP93XX_TIMER2_VALUE    EP93XX_TIMER_REG(0x24)
  93 +#define EP93XX_TIMER2_CONTROL  EP93XX_TIMER_REG(0x28)
  94 +#define EP93XX_TIMER2_CLEAR    EP93XX_TIMER_REG(0x2c)
  95 +
  96 +/*
  97 + * Register bit definitions
  98 + */
  99 +#define TSSETUP_SDLY_MASK      0x000003FF
 100 +#define TSSETUP_SDLY_SHIFT     0
 101 +#define TSSETUP_NSMP_4         0x00000000
 102 +#define TSSETUP_NSMP_8         0x00000400
 103 +#define TSSETUP_NSMP_16                0x00000800
 104 +#define TSSETUP_NSMP_32                0x00000C00
 105 +#define TSSETUP_NSMP_MASK      0x00000C00
 106 +#define TSSETUP_DEV_4          0x00000000
 107 +#define TSSETUP_DEV_8          0x00001000
 108 +#define TSSETUP_DEV_12         0x00002000
 109 +#define TSSETUP_DEV_16         0x00003000
 110 +#define TSSETUP_DEV_24         0x00004000
 111 +#define TSSETUP_DEV_32         0x00005000
 112 +#define TSSETUP_DEV_64         0x00006000
 113 +#define TSSETUP_DEV_128                0x00007000
 114 +#define TSSETUP_ENABLE         0x00008000
 115 +#define TSSETUP_DLY_MASK       0x03FF0000
 116 +#define TSSETUP_DLY_SHIFT      16
 117 +#define TSSETUP_TDTCT          0x80000000
 118 +
 119 +#define TSMAXMIN_XMIN_MASK     0x000000FF
 120 +#define TSMAXMIN_XMIN_SHIFT    0
 121 +#define TSMAXMIN_YMIN_MASK     0x0000FF00
 122 +#define TSMAXMIN_YMIN_SHIFT    8
 123 +#define TSMAXMIN_XMAX_MASK     0x00FF0000
 124 +#define TSMAXMIN_XMAX_SHIFT    16
 125 +#define TSMAXMIN_YMAX_MASK     0xFF000000
 126 +#define TSMAXMIN_YMAX_SHIFT    24
 127 +
 128 +#define TSXYRESULT_X_MASK      0x00000FFF
 129 +#define TSXYRESULT_X_SHIFT     0
 130 +#define TSXYRESULT_AD_MASK     0x0000FFFF
 131 +#define TSXYRESULT_AD_SHIFT    0
 132 +#define TSXYRESULT_Y_MASK      0x0FFF0000
 133 +#define TSXYRESULT_Y_SHIFT     16
 134 +#define TSXYRESULT_SDR         0x80000000
 135 +
 136 +#define TSX_SAMPLE_MASK                0x00003FFF
 137 +#define TSX_SAMPLE_SHIFT       0x00
 138 +#define TSY_SAMPLE_MASK                0x3FFF0000
 139 +#define TSY_SAMPLE_SHIFT       0x10
 140 +
 141 +#define TSSETUP2_TINT          0x00000001
 142 +#define TSSETUP2_NICOR         0x00000002
 143 +#define TSSETUP2_PINT          0x00000004
 144 +#define TSSETUP2_PENSTS                0x00000008
 145 +#define TSSETUP2_PINTEN                0x00000010
 146 +#define TSSETUP2_DEVINT                0x00000020
 147 +#define TSSETUP2_DINTEN                0x00000040
 148 +#define TSSETUP2_DTMEN         0x00000080
 149 +#define TSSETUP2_DISDEV                0x00000100
 150 +#define TSSETUP2_NSIGND                0x00000200
 151 +#define TSSETUP2_S28EN         0x00000400
 152 +#define TSSETUP2_RINTEN                0x00000800
 153 +
 154 +#define TSXYRESULT_SDR         0x80000000
 155 +
 156 +/*
 157 + * These are used as trigger levels to know when we have pen up/down.
 158 + * The rules:
 159 + * 1.  TS_HEAVY_INV_PRESSURE < TS_LIGHT_INV_PRESSURE because these
 160 + *    are Inverse pressure.
 161 + * 2.  Any touch lighter than TS_LIGHT_INV_PRESSURE is a pen up.
 162 + * 3.  Any touch heavier than TS_HEAVY_INV_PRESSURE is a pen down.
 163 + */
 164 +#define TS_HEAVY_INV_PRESSURE 0xFE0 /* C00 */
 165 +#define TS_LIGHT_INV_PRESSURE 0xFFF /* e00 */
 166 +
 167 +/*
 168 + * If the x, y, or inverse pressure changes more than these values
 169 + * between two succeeding points, the point is not reported.
 170 + */
 171 +#define TS_MAX_VALID_XY_CHANGE         0x300
 172 +#define TS_MAX_VALID_PRESSURE_CHANGE   0x100
 173 +
 174 +/*
 175 + * This is the minimum Z1 Value that is valid.
 176 + */
 177 +#define MIN_Z1_VALUE 0x50
 178 +
 179 +/*
 180 + * Settling delay for taking each ADC measurement.  Increase this
 181 + * if ts is jittery.
 182 + */
 183 +#define EP93XX_TS_ADC_DELAY_USEC 2000
 184 +
 185 +/*
 186 + * Delay between TS points.
 187 + */
 188 +#define EP93XX_TS_PER_POINT_DELAY_USEC 10000
 189 +
 190 +/*
 191 + * A few more macros...
 192 + */
 193 +#define TSSETUP_DEFAULT  (TSSETUP_NSMP_32 | TSSETUP_DEV_64 |  \
 194 +                         ((128<<TSSETUP_SDLY_SHIFT) & TSSETUP_SDLY_MASK) | \
 195 +                         ((128<<TSSETUP_DLY_SHIFT)  & TSSETUP_DLY_MASK))
 196 +
 197 +#define TSSETUP2_DEFAULT (TSSETUP2_NSIGND)
 198 +
 199 +/*
 200 + * For now, we use one of the minor numbers from the local/experimental
 201 + * range.
 202 + */
 203 +#define EP93XX_TS_MINOR 240
 204 +
 205 +/*
 206 + * Static Declarations
 207 + */
 208 +static unsigned int   guiLastX, guiLastY;
 209 +static unsigned int   guiLastInvPressure;
 210 +
 211 +struct TouchScreenSample
 212 +{
 213 +    int currentX;
 214 +    int currentY;
 215 +    int currentButton;
 216 +    int currentPressure;
 217 +    struct timeval currentTime;
 218 +};
 219 +
 220 +/*
 221 + * This must match the structure in tslib.
 222 + */
 223 +struct ts_sample {
 224 +    int x;
 225 +    int y;
 226 +    unsigned int pressure;
 227 +    struct timeval tv;
 228 +};
 229 +
 230 +static struct TouchScreenSample gSample;
 231 +static int bFreshTouchData;
 232 +static int bCurrentPenDown;
 233 +
 234 +static DECLARE_WAIT_QUEUE_HEAD(queue);
 235 +static DEFINE_SEMAPHORE(open_sem);
 236 +static DEFINE_SPINLOCK(event_buffer_lock);
 237 +static struct fasync_struct *ep93xx_fasync;
 238 +
 239 +/*
 240 + * Typedef Declarations
 241 + */
 242 +typedef enum {
 243 +    TS_MODE_UN_INITIALIZED,
 244 +    TS_MODE_HARDWARE_SCAN,
 245 +    TS_MODE_SOFT_SCAN
 246 +} ts_mode_t;
 247 +
 248 +static ts_mode_t gScanningMode;
 249 +
 250 +typedef enum{
 251 +    TS_STATE_STOPPED = 0,
 252 +    TS_STATE_Z1,
 253 +    TS_STATE_Z2,
 254 +    TS_STATE_Y,
 255 +    TS_STATE_X,
 256 +    TS_STATE_DONE
 257 +} ts_states_t;
 258 +
 259 +typedef struct
 260 +{
 261 +    unsigned int uiX;
 262 +    unsigned int uiY;
 263 +    unsigned int uiZ1;
 264 +    unsigned int uiZ2;
 265 +    ts_states_t  state;
 266 +} ts_struct_t;
 267 +
 268 +static ts_struct_t sTouch;
 269 +
 270 +/*
 271 + * From the spec, here's how to set up the touch screen's switch registers.
 272 + */
 273 +typedef struct
 274 +{
 275 +    unsigned int uiDetect;
 276 +    unsigned int uiDischarge;
 277 +    unsigned int uiXSample;
 278 +    unsigned int uiYSample;
 279 +    unsigned int uiSwitchZ1;
 280 +    unsigned int uiSwitchZ2;
 281 +}SwitchStructType;
 282 +
 283 +/*
 284 + * Here's the switch settings for a 4-wire touchscreen.  See the spec
 285 + * for how to handle a 4, 7, or 8-wire.
 286 + */
 287 +const static SwitchStructType sSwitchSettings =
 288 +/* s28en=0 */
 289 +/*   TSDetect    TSDischarge TSXSample   TSYSample   SwitchZ1    SwitchZ2 */
 290 +    {0x00403604, 0x0007fe04, 0x00081604, 0x00104601, 0x00101601, 0x00101608};
 291 +
 292 +/*
 293 + * Function declarations
 294 + */
 295 +static void ep93xx_ts_set_direct(unsigned int uiADCSwitch);
 296 +static irqreturn_t ep93xx_ts_isr(int irq, void *dev_id);
 297 +static irqreturn_t ep93xx_timer2_isr(int irq, void *dev_id);
 298 +static void ee93xx_ts_evt_add(int button, int dX, int dY, int Pressure);
 299 +static ssize_t ep93xx_ts_read(struct file *filp, char *buf,
 300 +       size_t count, loff_t *l);
 301 +static unsigned int ep93xx_ts_poll(struct file *filp, poll_table *wait);
 302 +static int ep93xx_ts_open(struct inode *inode, struct file *filp);
 303 +static int ep93xx_ts_fasync(int fd, struct file *filp, int on);
 304 +static int ep93xx_ts_release(struct inode *inode, struct file *filp);
 305 +static ssize_t ep93xx_ts_write(struct file *file, const char *buffer,
 306 +               size_t count, loff_t *ppos);
 307 +static void ep93xx_ts_setup(void);
 308 +static void ep93xx_ts_shutdown(void);
 309 +int __init ep93xx_ts_init(void);
 310 +void __exit ep93xx_ts_exit(void);
 311 +static unsigned int CalculateInvPressure(void);
 312 +static unsigned int ADCGetData(unsigned int uiSamples, unsigned int uiMaxDiff);
 313 +static void TS_Soft_Scan_Mode(void);
 314 +static void TS_Hardware_Scan_Mode(void);
 315 +static void ProcessPointData(void);
 316 +static void Set_Timer2_uSec(unsigned int Delay_mSec);
 317 +static void Stop_Timer2(void);
 318 +
 319 +/*
 320 + *  ep93xx_ts_isr
 321 + */
 322 +static irqreturn_t ep93xx_ts_isr(int irq, void *dev_id)
 323 +{
 324 +    /*
 325 +     * Note that we don't clear the interrupt here.  The interrupt
 326 +     * gets cleared in TS_Soft_Scan_Mode when the TS ENABLE
 327 +     * bit is cleared.
 328 +     */
 329 +
 330 +    /*
 331 +     * Set the ts to manual polling mode and schedule a callback.
 332 +     * That way we can return from the isr in a reasonable amount of
 333 +     * time and process the touch in the callback after a brief delay.
 334 +     */
 335 +    TS_Soft_Scan_Mode();
 336 +
 337 +    return(IRQ_HANDLED);
 338 +}
 339 +
 340 +/*
 341 + * Save the current ts 'event' in an atomic fashion.
 342 + */
 343 +static void ee93xx_ts_evt_add(int buttons, int iX, int iY, int iPressure)
 344 +{
 345 +    /*
 346 +     * Note the event, but use spinlocks to keep it from getting
 347 +     * halfway read if we get interrupted.
 348 +     */
 349 +
 350 +    spin_lock(&event_buffer_lock);
 351 +
 352 +    gSample.currentX        = iX;
 353 +    gSample.currentY        = iY;
 354 +    gSample.currentButton   = buttons;
 355 +    gSample.currentPressure = iPressure;
 356 +    bFreshTouchData         = 1;
 357 +    do_gettimeofday(&gSample.currentTime);
 358 +
 359 +    spin_unlock(&event_buffer_lock);
 360 +
 361 +    kill_fasync(&ep93xx_fasync, SIGIO, POLL_IN);
 362 +    wake_up_interruptible(&queue);
 363 +}
 364 +
 365 +
 366 +static ssize_t ep93xx_ts_read(struct file *filp, char *buf, size_t count, loff_t *l)
 367 +{
 368 +    unsigned short data[3];
 369 +    struct  ts_sample   ts_data;
 370 +    int     iReturn = -EFAULT;
 371 +
 372 +    if (!bFreshTouchData)
 373 +    {
 374 +       iReturn = 0;
 375 +    }
 376 +    else if (count == sizeof(data))
 377 +    {
 378 +       spin_lock_irq(&event_buffer_lock);
 379 +       bFreshTouchData = 0;
 380 +       data[0] = gSample.currentX;
 381 +       data[1] = gSample.currentY;
 382 +       data[2] = gSample.currentButton;
 383 +
 384 +       spin_unlock_irq(&event_buffer_lock);
 385 +
 386 +       if (copy_to_user(buf, data, sizeof data))
 387 +           return -EFAULT;
 388 +
 389 +       count -= sizeof(data);
 390 +
 391 +       /* return the # of bytes that got read */
 392 +       iReturn = sizeof(data) ;
 393 +    }
 394 +    else if (count == sizeof(struct ts_sample) )
 395 +    {
 396 +       spin_lock_irq(&event_buffer_lock);
 397 +       bFreshTouchData = 0;
 398 +       ts_data.x           = gSample.currentX;
 399 +       ts_data.y           = gSample.currentY;
 400 +       ts_data.pressure    = gSample.currentPressure;
 401 +       ts_data.tv          = gSample.currentTime;
 402 +       spin_unlock_irq(&event_buffer_lock);
 403 +
 404 +       if (copy_to_user(buf, &ts_data, sizeof(struct ts_sample)))
 405 +       {
 406 +           iReturn = -EFAULT;
 407 +       }
 408 +       else
 409 +       {
 410 +           count -= sizeof(ts_data);
 411 +           iReturn = sizeof(ts_data);
 412 +       }
 413 +    }
 414 +
 415 +    return iReturn;
 416 +}
 417 +
 418 +static unsigned int ep93xx_ts_poll(struct file *filp, poll_table *wait)
 419 +{
 420 +    poll_wait(filp, &queue, wait);
 421 +
 422 +    if (bFreshTouchData)
 423 +    {
 424 +       return POLLIN | POLLRDNORM;
 425 +    }
 426 +
 427 +    return 0;
 428 +}
 429 +
 430 +static int ep93xx_ts_open(struct inode *inode, struct file *filp)
 431 +{
 432 +    if (down_trylock(&open_sem))
 433 +    {
 434 +       return -EBUSY;
 435 +    }
 436 +
 437 +    ep93xx_ts_setup();
 438 +
 439 +    return 0;
 440 +}
 441 +
 442 +/*
 443 + * Asynchronous I/O support.
 444 + */
 445 +static int ep93xx_ts_fasync(int fd, struct file *filp, int on)
 446 +{
 447 +    int retval;
 448 +
 449 +    retval = fasync_helper(fd, filp, on, &ep93xx_fasync);
 450 +    if (retval < 0)
 451 +    {
 452 +       return retval;
 453 +    }
 454 +
 455 +    return 0;
 456 +}
 457 +
 458 +static int ep93xx_ts_release(struct inode *inode, struct file *filp)
 459 +{
 460 +    Stop_Timer2();
 461 +
 462 +    /*
 463 +     * Call our async I/O support to request that this file
 464 +     * cease to be used for async I/O.
 465 +     */
 466 +    ep93xx_ts_fasync(-1, filp, 0);
 467 +
 468 +    ep93xx_ts_shutdown();
 469 +
 470 +    up(&open_sem);
 471 +
 472 +    return 0;
 473 +}
 474 +
 475 +static ssize_t ep93xx_ts_write(struct file *file, const char *buffer, size_t count,
 476 +              loff_t *ppos)
 477 +{
 478 +    return -EINVAL;
 479 +}
 480 +
 481 +
 482 +static int ep93xx_ts_ioctl(struct inode *inode, struct file *file, uint command, ulong u)
 483 +{
 484 +    static const int         version = EV_VERSION;
 485 +    static const u_int32_t   bit =(1 << EV_ABS);
 486 +    static const u_int32_t   absbit = (1 << ABS_X) | (1 << ABS_Y) | (1 << ABS_PRESSURE);
 487 +    int         iReturn ;
 488 +    int         i = 0;
 489 +
 490 +    switch(command)
 491 +    {
 492 +       case EVIOCGVERSION:
 493 +           i = copy_to_user((void __user *)u, (void *)version, sizeof(version));
 494 +           iReturn = i ? -EFAULT : 0;
 495 +           break;
 496 +
 497 +       case EVIOCGBIT(0,sizeof(u_int32_t) * 8) :
 498 +           i = copy_to_user((void __user *)u, (void *)bit, sizeof(bit));
 499 +           iReturn = i ? -EFAULT : 0;
 500 +           break;
 501 +
 502 +       case EVIOCGBIT(EV_ABS, sizeof(absbit) * 8):
 503 +           i = copy_to_user((void __user *)u, (void *)absbit, sizeof(absbit));
 504 +           iReturn = i ? -EFAULT : 0;
 505 +           break;
 506 +       default:
 507 +           iReturn = -1;
 508 +           break;
 509 +    }
 510 +
 511 +    return iReturn;
 512 +}
 513 +
 514 +static struct file_operations ep93xx_ts_fops = {
 515 +    owner:      THIS_MODULE,
 516 +    read:       ep93xx_ts_read,
 517 +    write:      ep93xx_ts_write,
 518 +    poll:       ep93xx_ts_poll,
 519 +    open:       ep93xx_ts_open,
 520 +    unlocked_ioctl:      ep93xx_ts_ioctl,
 521 +    release:    ep93xx_ts_release,
 522 +    fasync:     ep93xx_ts_fasync,
 523 +};
 524 +
 525 +static struct miscdevice ep93xx_ts_miscdev =
 526 +{
 527 +       EP93XX_TS_MINOR,
 528 +       "ep93xx_ts",
 529 +       &ep93xx_ts_fops
 530 +};
 531 +
 532 +void ep93xx_ts_setup(void)
 533 +{
 534 +    unsigned int uiKTDIV, uiTSXYMaxMin;
 535 +
 536 +    /*
 537 +     * Set the TSEN bit in KTDIV so that we are enabling the clock
 538 +     * for the touchscreen.
 539 +     */
 540 +    uiKTDIV = __raw_readl(EP93XX_SYSCON_KEYTCHCLKDIV);
 541 +    uiKTDIV |= EP93XX_SYSCON_KEYTCHCLKDIV_TSEN;
 542 +    ep93xx_syscon_swlocked_write(uiKTDIV, EP93XX_SYSCON_KEYTCHCLKDIV);
 543 +
 544 +    /*
 545 +     * Program the EP93XX_TOUCHSCREEN_SETUP and TSSetup2 registers.
 546 +     */
 547 +    __raw_writel(TSSETUP_DEFAULT, EP93XX_TOUCHSCREEN_SETUP);
 548 +    __raw_writel(TSSETUP2_DEFAULT, EP93XX_TOUCHSCREEN_SETUP2);
 549 +
 550 +    /*
 551 +     * Set the the touch settings.
 552 +     */
 553 +    __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
 554 +    __raw_writel(sSwitchSettings.uiDischarge, EP93XX_TOUCHSCREEN_DIRECT);
 555 +
 556 +    __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
 557 +    __raw_writel(sSwitchSettings.uiDischarge, EP93XX_TOUCHSCREEN_DISCHARGE);
 558 +
 559 +    __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
 560 +    __raw_writel(sSwitchSettings.uiSwitchZ1, EP93XX_TOUCHSCREEN_XSAMPLE);
 561 +
 562 +    __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
 563 +    __raw_writel(sSwitchSettings.uiSwitchZ2, EP93XX_TOUCHSCREEN_YSAMPLE);
 564 +
 565 +    __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
 566 +    __raw_writel(sSwitchSettings.uiDetect, EP93XX_TOUCHSCREEN_DETECT);
 567 +
 568 +    /*
 569 +     * X,YMin set to 0x40 = have to drag that many pixels for a new irq.
 570 +     * X,YMax set to 0x40 = 1024 pixels is the maximum movement within the
 571 +     * time scan limit.
 572 +     */
 573 +    uiTSXYMaxMin =  (50   << TSMAXMIN_XMIN_SHIFT) & TSMAXMIN_XMIN_MASK;
 574 +    uiTSXYMaxMin |= (50   << TSMAXMIN_YMIN_SHIFT) & TSMAXMIN_YMIN_MASK;
 575 +    uiTSXYMaxMin |= (0xff << TSMAXMIN_XMAX_SHIFT) & TSMAXMIN_XMAX_MASK;
 576 +    uiTSXYMaxMin |= (0xff << TSMAXMIN_YMAX_SHIFT) & TSMAXMIN_YMAX_MASK;
 577 +    __raw_writel(uiTSXYMaxMin, EP93XX_TOUCHSCREEN_XYMAXMIN);
 578 +
 579 +    bCurrentPenDown = 0;
 580 +    bFreshTouchData = 0;
 581 +    guiLastX = 0;
 582 +    guiLastY = 0;
 583 +    guiLastInvPressure = 0xffffff;
 584 +
 585 +    /*
 586 +     * Enable the touch screen scanning engine.
 587 +     */
 588 +    TS_Hardware_Scan_Mode();
 589 +}
 590 +
 591 +/*
 592 + * ep93xx_ts_shutdown
 593 + *
 594 + */
 595 +static void
 596 +ep93xx_ts_shutdown(void)
 597 +{
 598 +    unsigned int uiKTDIV;
 599 +
 600 +    sTouch.state = TS_STATE_STOPPED;
 601 +    Stop_Timer2();
 602 +
 603 +    /*
 604 +     * Disable the scanning engine.
 605 +     */
 606 +    __raw_writel(0, EP93XX_TOUCHSCREEN_SETUP);
 607 +    __raw_writel(0, EP93XX_TOUCHSCREEN_SETUP2);
 608 +
 609 +    /*
 610 +     * Clear the TSEN bit in KTDIV so that we are disabling the clock
 611 +     * for the touchscreen.
 612 +     */
 613 +    uiKTDIV = __raw_readl(EP93XX_SYSCON_KEYTCHCLKDIV);
 614 +    uiKTDIV &= ~EP93XX_SYSCON_KEYTCHCLKDIV_TSEN;
 615 +    ep93xx_syscon_swlocked_write(uiKTDIV, EP93XX_SYSCON_KEYTCHCLKDIV);
 616 +
 617 +} /* ep93xx_ts_shutdown */
 618 +
 619 +static irqreturn_t ep93xx_timer2_isr(int irq, void *dev_id)
 620 +{
 621 +    switch(sTouch.state)
 622 +    {
 623 +       case TS_STATE_STOPPED:
 624 +           TS_Hardware_Scan_Mode();
 625 +           break;
 626 +
 627 +       /*
 628 +        * Get the Z1 value for pressure measurement and set up
 629 +        * the switch register for getting the Z2 measurement.
 630 +        */
 631 +       case TS_STATE_Z1:
 632 +           Set_Timer2_uSec(EP93XX_TS_ADC_DELAY_USEC);
 633 +           sTouch.uiZ1 = ADCGetData(2, 200);
 634 +           ep93xx_ts_set_direct(sSwitchSettings.uiSwitchZ2);
 635 +           sTouch.state = TS_STATE_Z2;
 636 +           break;
 637 +
 638 +       /*
 639 +        * Get the Z2 value for pressure measurement and set up
 640 +        * the switch register for getting the Y measurement.
 641 +        */
 642 +       case TS_STATE_Z2:
 643 +           sTouch.uiZ2 = ADCGetData(2, 200);
 644 +           ep93xx_ts_set_direct(sSwitchSettings.uiYSample);
 645 +           sTouch.state = TS_STATE_Y;
 646 +           break;
 647 +
 648 +       /*
 649 +        * Get the Y value and set up the switch register for
 650 +        * getting the X measurement.
 651 +        */
 652 +       case TS_STATE_Y:
 653 +           sTouch.uiY = ADCGetData(4, 20);
 654 +           ep93xx_ts_set_direct(sSwitchSettings.uiXSample);
 655 +           sTouch.state = TS_STATE_X;
 656 +           break;
 657 +
 658 +       /*
 659 +        * Read the X value.  This is the last of the 4 adc values
 660 +        * we need so we continue on to process the data.
 661 +        */
 662 +       case TS_STATE_X:
 663 +           Stop_Timer2();
 664 +
 665 +           sTouch.uiX = ADCGetData(4, 20);
 666 +
 667 +           __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
 668 +           __raw_writel(sSwitchSettings.uiDischarge, EP93XX_TOUCHSCREEN_DIRECT);
 669 +
 670 +           sTouch.state = TS_STATE_DONE;
 671 +
 672 +           /*
 673 +            * Process this set of ADC readings.
 674 +            */
 675 +           ProcessPointData();
 676 +
 677 +           break;
 678 +
 679 +       /*
 680 +        * Shouldn't get here.  But if we do, we can recover...
 681 +        */
 682 +       case TS_STATE_DONE:
 683 +           TS_Hardware_Scan_Mode();
 684 +           break;
 685 +    }
 686 +
 687 +    /*
 688 +     * Clear the timer2 interrupt.
 689 +     */
 690 +    __raw_writel(1, EP93XX_TIMER2_CLEAR);
 691 +    return(IRQ_HANDLED);
 692 +}
 693 +
 694 +/*---------------------------------------------------------------------
 695 + * ProcessPointData
 696 + *
 697 + * This routine processes the ADC data into usable point data and then
 698 + * puts the driver into hw or sw scanning mode before returning.
 699 + *
 700 + * We calculate inverse pressure (lower number = more pressure) then
 701 + * do a hystheresis with the two pressure values 'light' and 'heavy'.
 702 + *
 703 + * If we are above the light, we have pen up.
 704 + * If we are below the heavy we have pen down.
 705 + * As long as the pressure stays below the light, pen stays down.
 706 + * When we get above the light again, pen goes back up.
 707 + *
 708 + */
 709 +static void ProcessPointData(void)
 710 +{
 711 +    int  bValidPoint = 0;
 712 +    unsigned int   uiXDiff, uiYDiff, uiInvPressureDiff;
 713 +    unsigned int   uiInvPressure;
 714 +
 715 +    /*
 716 +     * Calculate the current pressure.
 717 +     */
 718 +    uiInvPressure = CalculateInvPressure();
 719 +
 720 +    /*
 721 +     * If pen pressure is so light that it is greater than the 'max' setting
 722 +     * then we consider this to be a pen up.
 723 +     */
 724 +    if (uiInvPressure >= TS_LIGHT_INV_PRESSURE)
 725 +    {
 726 +       bCurrentPenDown = 0;
 727 +       ee93xx_ts_evt_add(0, guiLastX, guiLastY, 0);
 728 +       TS_Hardware_Scan_Mode();
 729 +       return;
 730 +    }
 731 +
 732 +    /*
 733 +     * Hysteresis:
 734 +     * If the pen pressure is hard enough to be less than the 'min' OR
 735 +     * the pen is already down and is still less than the 'max'...
 736 +     */
 737 +    if ((uiInvPressure < TS_HEAVY_INV_PRESSURE) ||
 738 +       (bCurrentPenDown && (uiInvPressure < TS_LIGHT_INV_PRESSURE)))
 739 +    {
 740 +       if (bCurrentPenDown)
 741 +       {
 742 +           /*
 743 +            * If pen was previously down, check the difference between
 744 +            * the last sample and this one... if the difference between
 745 +            * samples is too great, ignore the sample.
 746 +            */
 747 +           uiXDiff = abs(guiLastX - sTouch.uiX);
 748 +           uiYDiff = abs(guiLastY - sTouch.uiY);
 749 +           uiInvPressureDiff = abs(guiLastInvPressure - uiInvPressure);
 750 +
 751 +           if (uiXDiff < TS_MAX_VALID_XY_CHANGE
 752 +               && uiYDiff < TS_MAX_VALID_XY_CHANGE
 753 +               && uiInvPressureDiff < TS_MAX_VALID_PRESSURE_CHANGE)
 754 +           {
 755 +               bValidPoint = 1;
 756 +           }
 757 +       }
 758 +       else
 759 +       {
 760 +           bValidPoint = 1;
 761 +       }
 762 +
 763 +       /*
 764 +        * If either the pen was put down or dragged make a note of it.
 765 +        */
 766 +       if (bValidPoint)
 767 +       {
 768 +           guiLastX = sTouch.uiX;
 769 +           guiLastY = sTouch.uiY;
 770 +           guiLastInvPressure = uiInvPressure;
 771 +           bCurrentPenDown = 1;
 772 +           ee93xx_ts_evt_add(1, sTouch.uiX, sTouch.uiY,
 773 +                             0x7000000 / uiInvPressure);
 774 +       }
 775 +
 776 +       TS_Soft_Scan_Mode();
 777 +       return;
 778 +    }
 779 +
 780 +    TS_Hardware_Scan_Mode();
 781 +}
 782 +
 783 +static void ep93xx_ts_set_direct(unsigned int uiADCSwitch)
 784 +{
 785 +    unsigned int uiResult;
 786 +
 787 +    /*
 788 +     * Set the switch settings in the direct register.
 789 +     */
 790 +    __raw_writel(0xaa, EP93XX_TOUCHSCREEN_SWLOCK);
 791 +    __raw_writel(uiADCSwitch, EP93XX_TOUCHSCREEN_DIRECT);
 792 +
 793 +    /*
 794 +     * Read and throw away the first sample.
 795 +     */
 796 +    do {
 797 +       uiResult = __raw_readl(EP93XX_TOUCHSCREEN_XYRESULT);
 798 +    } while (!(uiResult & TSXYRESULT_SDR));
 799 +
 800 +}
 801 +
 802 +static unsigned int ADCGetData(unsigned int uiSamples, unsigned int uiMaxDiff)
 803 +{
 804 +    unsigned int uiResult, uiValue, uiCount, uiLowest, uiHighest, uiSum, uiAve;
 805 +
 806 +    do
 807 +    {
 808 +       /*
 809 +        * Initialize our values.
 810 +        */
 811 +       uiLowest        = 0xfffffff;
 812 +       uiHighest       = 0;
 813 +       uiSum           = 0;
 814 +
 815 +       for (uiCount = 0; uiCount < uiSamples; uiCount++)
 816 +       {
 817 +           /*
 818 +            * Read the touch screen four more times and average.
 819 +            */
 820 +           do {
 821 +               uiResult = __raw_readl(EP93XX_TOUCHSCREEN_XYRESULT);
 822 +           } while (!(uiResult & TSXYRESULT_SDR));
 823 +
 824 +           uiValue = (uiResult & TSXYRESULT_AD_MASK) >> TSXYRESULT_AD_SHIFT;
 825 +           uiValue = ((uiValue >> 4) + ((1 + TSXYRESULT_X_MASK)>>1)) & TSXYRESULT_X_MASK;
 826 +
 827 +           /*
 828 +            * Add up the values.
 829 +            */
 830 +           uiSum += uiValue;
 831 +
 832 +           /*
 833 +            * Get the lowest and highest values.
 834 +            */
 835 +           if (uiValue < uiLowest)
 836 +           {
 837 +               uiLowest = uiValue;
 838 +           }
 839 +           if (uiValue > uiHighest)
 840 +           {
 841 +               uiHighest = uiValue;
 842 +           }
 843 +       }
 844 +    } while ((uiHighest - uiLowest) > uiMaxDiff);
 845 +
 846 +    /*
 847 +     * Calculate the Average value.
 848 +     */
 849 +    uiAve = uiSum / uiSamples;
 850 +
 851 +    return uiAve;
 852 +}
 853 +
 854 +/*
 855 + * CalculateInvPressure
 856 + *
 857 + * Is the Touch Valid.  Touch is not valid if the X or Y value is not
 858 + * in range and the pressure is not  enough.
 859 + *
 860 + * Touch resistance can be measured by the following formula:
 861 + *
 862 + *          Rx * X *     Z2
 863 + * Rtouch = --------- * (-- - 1)
 864 + *           4096        Z1
 865 + *
 866 + * This is simplified in the ration of Rtouch to Rx.  The lower the value, the
 867 + * higher the pressure.
 868 + *
 869 + *                     Z2
 870 + * InvPressure =  X * (-- - 1)
 871 + *                     Z1
 872 + */
 873 +static unsigned int CalculateInvPressure(void)
 874 +{
 875 +    unsigned int uiInvPressure;
 876 +
 877 +    /*
 878 +     * Check to see if the point is valid.
 879 +     */
 880 +    if (sTouch.uiZ1 < MIN_Z1_VALUE)
 881 +    {
 882 +       uiInvPressure = 0x10000;
 883 +    }
 884 +
 885 +    /*
 886 +     * Can omit the pressure calculation if you need to get rid of the division.
 887 +     */
 888 +    else
 889 +    {
 890 +       uiInvPressure = ((sTouch.uiX * sTouch.uiZ2) / sTouch.uiZ1) - sTouch.uiX;
 891 +    }
 892 +
 893 +    return uiInvPressure;
 894 +}
 895 +
 896 +/*
 897 + * TS_Hardware_Scan_Mode
 898 + *
 899 + * Enables the ep93xx ts scanning engine so that when the pen goes down
 900 + * we will get an interrupt.
 901 + */
 902 +static void TS_Hardware_Scan_Mode(void)
 903 +{
 904 +    unsigned int uiDevCfg;
 905 +
 906 +    /*
 907 +     * Disable the soft scanning engine.
 908 +     */
 909 +    sTouch.state = TS_STATE_STOPPED;
 910 +    Stop_Timer2();
 911 +
 912 +    /*
 913 +     * Clear the TIN (Touchscreen INactive) bit so we can go to
 914 +     * automatic scanning mode.
 915 +     */
 916 +    uiDevCfg = __raw_readl(EP93XX_SYSCON_DEVCFG);
 917 +    ep93xx_syscon_swlocked_write(uiDevCfg & ~EP93XX_SYSCON_DEVCFG_TIN,
 918 +                                EP93XX_SYSCON_DEVCFG);
 919 +
 920 +    /*
 921 +     * Enable the touch screen scanning state machine by setting
 922 +     * the ENABLE bit.
 923 +     */
 924 +    __raw_writel(TSSETUP_DEFAULT | TSSETUP_ENABLE, EP93XX_TOUCHSCREEN_SETUP);
 925 +
 926 +    /*
 927 +     * Set the flag to show that we are in interrupt mode.
 928 +     */
 929 +    gScanningMode = TS_MODE_HARDWARE_SCAN;
 930 +
 931 +    /*
 932 +     * Initialize EP93XX_TOUCHSCREEN_SETUP2 register.
 933 +     */
 934 +    __raw_writel(TSSETUP2_DEFAULT, EP93XX_TOUCHSCREEN_SETUP2);
 935 +
 936 +}
 937 +
 938 +/*
 939 + * TS_Soft_Scan_Mode
 940 + *
 941 + * Sets the touch screen to manual polling mode.
 942 + */
 943 +static void TS_Soft_Scan_Mode(void)
 944 +{
 945 +    unsigned int uiDevCfg;
 946 +
 947 +    if (gScanningMode != TS_MODE_SOFT_SCAN)
 948 +    {
 949 +       /*
 950 +        * Disable the touch screen scanning state machine by clearing
 951 +        * the ENABLE bit.
 952 +        */
 953 +       __raw_writel(TSSETUP_DEFAULT, EP93XX_TOUCHSCREEN_SETUP);
 954 +
 955 +       /*
 956 +        * Set the TIN bit so we can do manual touchscreen polling.
 957 +        */
 958 +       uiDevCfg = __raw_readl(EP93XX_SYSCON_DEVCFG);
 959 +       ep93xx_syscon_swlocked_write(uiDevCfg | EP93XX_SYSCON_DEVCFG_TIN,
 960 +                                    EP93XX_SYSCON_DEVCFG);
 961 +    }
 962 +
 963 +    /*
 964 +     * Set the switch register up for the first ADC reading
 965 +     */
 966 +    ep93xx_ts_set_direct(sSwitchSettings.uiSwitchZ1);
 967 +
 968 +    /*
 969 +     * Initialize our software state machine to know which ADC
 970 +     * reading to take
 971 +     */
 972 +    sTouch.state = TS_STATE_Z1;
 973 +
 974 +    /*
 975 +     * Set the timer so after a mSec or two settling delay it will
 976 +     * take the first ADC reading.
 977 +     */
 978 +    Set_Timer2_uSec(EP93XX_TS_PER_POINT_DELAY_USEC);
 979 +
 980 +    /*
 981 +     * Note that we are in sw scanning mode not hw scanning mode.
 982 +     */
 983 +    gScanningMode = TS_MODE_SOFT_SCAN;
 984 +
 985 +}
 986 +
 987 +static void Set_Timer2_uSec(unsigned int uiDelay_uSec)
 988 +{
 989 +    unsigned int uiClockTicks;
 990 +
 991 +    /*
 992 +     * Stop timer 2
 993 +     */
 994 +    __raw_writel(0, EP93XX_TIMER2_CONTROL);
 995 +
 996 +    uiClockTicks = ((uiDelay_uSec * 508) + 999) / 1000;
 997 +    __raw_writel(uiClockTicks, EP93XX_TIMER2_LOAD);
 998 +    __raw_writel(uiClockTicks, EP93XX_TIMER2_VALUE);
 999 +
1000 +    /*
1001 +     * Set up Timer 2 for 508 kHz clock and periodic mode.
1002 +     */
1003 +    __raw_writel(0xC8, EP93XX_TIMER2_CONTROL);
1004 +
1005 +}
1006 +
1007 +static void Stop_Timer2(void)
1008 +{
1009 +    __raw_writel(0, EP93XX_TIMER2_CONTROL);
1010 +}
1011 +
1012 +/*
1013 + * Initialization and exit routines
1014 + */
1015 +int __init ep93xx_ts_init(void)
1016 +{
1017 +    int retval;
1018 +
1019 +    retval = request_irq(IRQ_EP93XX_TOUCH, ep93xx_ts_isr,
1020 +                        IRQF_DISABLED, "ep93xx_ts", 0);
1021 +    if (retval)
1022 +    {
1023 +       printk(KERN_WARNING "ep93xx_ts: failed to get touchscreen IRQ\n");
1024 +       return retval;
1025 +    }
1026 +
1027 +    retval = request_irq(IRQ_EP93XX_TIMER2, ep93xx_timer2_isr,
1028 +                        IRQF_DISABLED, "ep93xx_timer2", 0);
1029 +    if (retval)
1030 +    {
1031 +       printk(KERN_WARNING "ep93xx_ts: failed to get timer2 IRQ\n");
1032 +       free_irq(IRQ_EP93XX_TOUCH, 0);
1033 +       return retval;
1034 +    }
1035 +
1036 +    misc_register(&ep93xx_ts_miscdev);
1037 +
1038 +    sTouch.state = TS_STATE_STOPPED;
1039 +    gScanningMode = TS_MODE_UN_INITIALIZED;
1040 +
1041 +    printk(KERN_NOTICE "ep93xx touchscreen driver configured for 4-wire operation\n");
1042 +
1043 +    return 0;
1044 +}
1045 +
1046 +void __exit ep93xx_ts_exit(void)
1047 +{
1048 +    Stop_Timer2();
1049 +
1050 +    free_irq(IRQ_EP93XX_TOUCH, 0);
1051 +    free_irq(IRQ_EP93XX_TIMER2, 0);
1052 +
1053 +    misc_deregister(&ep93xx_ts_miscdev);
1054 +}
1055 +
1056 +module_init(ep93xx_ts_init);
1057 +module_exit(ep93xx_ts_exit);
1058 +
1059 +MODULE_DESCRIPTION("Cirrus EP93xx touchscreen driver");
1060 +MODULE_SUPPORTED_DEVICE("touchscreen/ep93xx");
1061 +MODULE_LICENSE("GPL");