arch/mips/au1000/db1x00/mirage_ts.c

   1 /*
   2  * linux/arch/mips/au1000/db1x00/mirage_ts.c
   3  *
   4  * BRIEF MODULE DESCRIPTION
   5  *      Glue between Mirage board-specific touchscreen pieces
   6  *      and generic Wolfson Codec touchscreen support.
   7  *
   8  *      Based on pb1100_ts.c used in Hydrogen II.
   9  *
  10  * Copyright (c) 2003 Embedded Edge, LLC
  11  *              dan@embeddededge.com
  12  *
  13  *  This program is free software; you can redistribute  it and/or modify it
  14  *  under  the terms of  the GNU General  Public License as published by the
  15  *  Free Software Foundation;  either version 2 of the  License, or (at your
  16  *  option) any later version.
  17  *
  18  *  THIS  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR IMPLIED
  19  *  WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
  20  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
  21  *  NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT, INDIRECT,
  22  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  23  *  NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
  24  *  USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
  25  *  ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
  26  *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  27  *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  *
  29  *  You should have received a copy of the  GNU General Public License along
  30  *  with this program; if not, write  to the Free Software Foundation, Inc.,
  31  *  675 Mass Ave, Cambridge, MA 02139, USA.
  32  */
  33
  34 #include <linux/types.h>
  35 #include <linux/module.h>
  36 #include <linux/sched.h>
  37 #include <linux/kernel.h>
  38 #include <linux/init.h>
  39 #include <linux/fs.h>
  40 #include <linux/poll.h>
  41 #include <linux/proc_fs.h>
  42 #include <linux/smp.h>
  43 #include <linux/smp_lock.h>
  44 #include <linux/wait.h>
  45
  46 #include <asm/segment.h>
  47 #include <asm/irq.h>
  48 #include <asm/uaccess.h>
  49 #include <asm/delay.h>
  50 #include <asm/au1000.h>
  51
  52 /*
  53  *  Imported interface to Wolfson Codec driver.
  54  */
  55 extern void *wm97xx_ts_get_handle(int which);
  56 extern int wm97xx_ts_ready(void* ts_handle);
  57 extern void wm97xx_ts_set_cal(void* ts_handle, int xscale, int xtrans, int yscale, int ytrans);
  58 extern u16 wm97xx_ts_get_ac97(void* ts_handle, u8 reg);
  59 extern void wm97xx_ts_set_ac97(void* ts_handle, u8 reg, u16 val);
  60 extern int wm97xx_ts_read_data(void* ts_handle, long* x, long* y, long* pressure);
  61 extern void wm97xx_ts_send_data(void* ts_handle, long x, long y, long z);
  62
  63 int wm97xx_comodule_present = 1;
  64
  65
  66 #define TS_NAME "mirage_ts"
  67
  68 #define err(format, arg...) printk(KERN_ERR TS_NAME ": " format "\n" , ## arg)
  69 #define info(format, arg...) printk(KERN_INFO TS_NAME ": " format "\n" , ## arg)
  70 #define warn(format, arg...) printk(KERN_WARNING TS_NAME ": " format "\n" , ## arg)
  71 #define DPRINTK(format, arg...) printk("%s: " format "\n", __FUNCTION__ , ## arg)
  72
  73
  74 #define PEN_DOWN_IRQ    AU1000_GPIO_7
  75
  76 static struct task_struct *ts_task = 0;
  77 static DECLARE_COMPLETION(ts_complete);
  78 static DECLARE_WAIT_QUEUE_HEAD(pendown_wait);
  79
  80 #ifdef CONFIG_WM97XX_FIVEWIRETS
  81 static int release_pressure = 1;
  82 #else
  83 static int release_pressure = 50;
  84 #endif
  85
  86 typedef struct {
  87    long x;
  88    long y;
  89 } DOWN_EVENT;
  90
  91 #define SAMPLE_RATE     50      /* samples per second */
  92 #define PEN_DEBOUNCE    5       /* samples for settling - fn of SAMPLE_RATE */
  93 #define PEN_UP_TIMEOUT  10      /* in seconds */
  94 #define PEN_UP_SETTLE   5       /* samples per second */
  95
  96 static struct {
  97         int xscale;
  98         int xtrans;
  99         int yscale;
 100         int ytrans;
 101 } mirage_ts_cal =
 102 {
 103 #if 0
 104         .xscale   = 84,
 105         .xtrans = -157,
 106         .yscale   = 66,
 107         .ytrans = -150,
 108 #else
 109         .xscale   = 84,
 110         .xtrans = -150,
 111         .yscale   = 66,
 112         .ytrans = -146,
 113 #endif
 114 };
 115
 116
 117 static void pendown_irq(int irqnr, void *devid, struct pt_regs *regs)
 118 {
 119 //DPRINTK("got one 0x%x", au_readl(SYS_PINSTATERD));
 120         wake_up(&pendown_wait);
 121 }
 122
 123 static int ts_thread(void *id)
 124 {
 125         static int pen_was_down = 0;
 126         static DOWN_EVENT pen_xy;
 127         long x, y, z;
 128         void *ts;       /* handle */
 129         struct task_struct *tsk = current;
 130         int timeout = HZ / SAMPLE_RATE;
 131
 132         ts_task = tsk;
 133
 134         daemonize();
 135         tsk->tty = NULL;
 136         tsk->policy = SCHED_FIFO;
 137         tsk->rt_priority = 1;
 138         strcpy(tsk->comm, "touchscreen");
 139
 140         /* only want to receive SIGKILL */
 141         spin_lock_irq(&tsk->sigmask_lock);
 142         siginitsetinv(&tsk->blocked, sigmask(SIGKILL));
 143         recalc_sigpending(tsk);
 144         spin_unlock_irq(&tsk->sigmask_lock);
 145
 146         /* get handle for codec */
 147         ts = wm97xx_ts_get_handle(0);
 148
 149         /* proceed only after everybody is ready */
 150         wait_event_timeout(pendown_wait, wm97xx_ts_ready(ts), HZ/4);
 151
 152         /* board-specific calibration */
 153         wm97xx_ts_set_cal(ts,
 154                         mirage_ts_cal.xscale,
 155                         mirage_ts_cal.xtrans,
 156                         mirage_ts_cal.yscale,
 157                         mirage_ts_cal.ytrans);
 158
 159         /* route Wolfson pendown interrupts to our GPIO */
 160         au_sync();
 161         wm97xx_ts_set_ac97(ts, 0x4c, wm97xx_ts_get_ac97(ts, 0x4c) & ~0x0008);
 162         au_sync();
 163         wm97xx_ts_set_ac97(ts, 0x56, wm97xx_ts_get_ac97(ts, 0x56) & ~0x0008);
 164         au_sync();
 165         wm97xx_ts_set_ac97(ts, 0x52, wm97xx_ts_get_ac97(ts, 0x52) | 0x2008);
 166         au_sync();
 167
 168         for (;;) {
 169                 interruptible_sleep_on_timeout(&pendown_wait, timeout);
 170                 disable_irq(PEN_DOWN_IRQ);
 171                 if (signal_pending(tsk)) {
 172                         break;
 173                 }
 174
 175                 /* read codec */
 176                 if (!wm97xx_ts_read_data(ts, &x, &y, &z))
 177                         z = 0;  /* treat no-data and pen-up the same */
 178
 179                 if (signal_pending(tsk)) {
 180                         break;
 181                 }
 182
 183                 if (z >= release_pressure) {
 184                         y = ~y; /* top to bottom */
 185                         if (pen_was_down > 1 /*&& pen_was_down < PEN_DEBOUNCE*/) {//THXXX
 186                                 /* bounce ? */
 187                                 x = pen_xy.x;
 188                                 y = pen_xy.y;
 189                                 --pen_was_down;
 190                         } else if (pen_was_down <= 1) {
 191                                 pen_xy.x = x;
 192                                 pen_xy.y = y;
 193                                 if (pen_was_down)
 194                                         wm97xx_ts_send_data(ts, x, y, z);
 195                                 pen_was_down = PEN_DEBOUNCE;
 196                         }
 197                         //wm97xx_ts_send_data(ts, x, y, z);
 198                         timeout = HZ / SAMPLE_RATE;
 199                 } else {
 200                         if (pen_was_down) {
 201                                 if (--pen_was_down)
 202                                         z = release_pressure;
 203                                 else //THXXX
 204                                 wm97xx_ts_send_data(ts, pen_xy.x, pen_xy.y, z);
 205                         }
 206                         /* The pendown signal takes some time to settle after
 207                          * reading the pen pressure so wait a little
 208                          * before enabling the pen.
 209                          */
 210                         if (! pen_was_down) {
 211 //                              interruptible_sleep_on_timeout(&pendown_wait, HZ / PEN_UP_SETTLE);
 212                                 timeout = HZ * PEN_UP_TIMEOUT;
 213                         }
 214                 }
 215                 enable_irq(PEN_DOWN_IRQ);
 216         }
 217         enable_irq(PEN_DOWN_IRQ);
 218         ts_task = NULL;
 219         complete(&ts_complete);
 220         return 0;
 221 }
 222
 223 static int __init ts_mirage_init(void)
 224 {
 225         int ret;
 226
 227         /* pen down signal is connected to GPIO 7 */
 228
 229         ret = request_irq(PEN_DOWN_IRQ, pendown_irq, 0, "ts-pendown", NULL);
 230         if (ret) {
 231                 err("unable to get pendown irq%d: [%d]", PEN_DOWN_IRQ, ret);
 232                 return ret;
 233         }
 234
 235         lock_kernel();
 236         ret = kernel_thread(ts_thread, NULL, CLONE_FS | CLONE_FILES);
 237         if (ret < 0) {
 238                 unlock_kernel();
 239                 return ret;
 240         }
 241         unlock_kernel();
 242
 243         info("Mirage touchscreen IRQ initialized.");
 244
 245         return 0;
 246 }
 247
 248 static void __exit ts_mirage_exit(void)
 249 {
 250         if (ts_task) {
 251                 send_sig(SIGKILL, ts_task, 1);
 252                 wait_for_completion(&ts_complete);
 253         }
 254
 255         free_irq(PEN_DOWN_IRQ, NULL);
 256 }
 257
 258 module_init(ts_mirage_init);
 259 module_exit(ts_mirage_exit);
 260