drivers/input/touchscreen/omap/ts_hx.c

   1 /*
   2  * input/touchscreen/omap/ts_hx.c
   3  * touchscreen support for OMAP H3 and H2  boards
   4  *
   5  * Copyright (c) 2002 MontaVista Software Inc.
   6  * Copyright (c) 2004 Texas Instruments, Inc.
   7  *
   8  * Assembled using driver code copyright the companies above.
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  23  *
  24  * History:
  25  * 9/12/2004    Srinath Modified and integrated  H2 and H3 code
  26  *
  27  */
  28
  29 #include <linux/input.h>
  30 #include <linux/device.h>
  31 #include <asm/mach-types.h>
  32 #include <asm/arch/gpio.h>
  33 #include <asm/arch/mux.h>
  34 #include <asm/arch/hardware.h>
  35 #include <asm/hardware/tsc2101.h>
  36
  37 #include "../drivers/ssi/omap-tsc2101.h"
  38 #include "omap_ts.h"
  39
  40 #define H2_GPIO_NUM             4
  41 #define H3_GPIO_NUM             48
  42 #define H6300_GPIO_NUM  2
  43
  44 #define OMAP_TSC2101_XRES                      500
  45 #define TOUCHSCREEN_DATA_REGISTERS_PAGE  0x0
  46 #define TOUCHSCREEN_CONTROL_REGISTERS_PAGE      0x1
  47 #define OMAP_TSC2101_READ_MAX              0x4
  48 #define TSC2101_GETSTATUS(ret)            (((ret) >> 11) & 0x1)
  49 #define TSC2101_MASKVAL                  0xFFF
  50 #define TSC2101_PRESSUREVAL(x)            ((x) << 12)
  51
  52 static int hx_ts_penup(void);
  53 static int hx_ts_probe(struct omap_ts_t *ts);
  54 static void hx_ts_read(u16 * data);
  55 static void hx_ts_enable(void);
  56 static void hx_ts_disable(void);
  57 #ifdef  MODULE
  58 static void hx_ts_remove(void);
  59 #endif
  60
  61 struct ts_device hx_ts = {
  62         .probe          = hx_ts_probe,
  63         .read           = hx_ts_read,
  64         .enable         = hx_ts_enable,
  65         .disable        = hx_ts_disable,
  66         .remove         = __exit_p(hx_ts_remove),
  67         .penup          = hx_ts_penup,
  68 };
  69
  70 static int hx_ts_penup(void)
  71 {
  72         int ret = 0;
  73         /* Read the status register */
  74         ret = omap_tsc2101_read(TOUCHSCREEN_CONTROL_REGISTERS_PAGE,
  75                                 TSC2101_TS_STATUS);
  76         /* Check for availability of data in status register */
  77         ret = TSC2101_GETSTATUS(ret);
  78         return !ret;
  79
  80 }
  81
  82 static int __init hx_ts_probe(struct omap_ts_t *ts)
  83 {
  84         unsigned        gpio;
  85
  86         if (machine_is_omap_h2()) {
  87                 gpio = H2_GPIO_NUM;
  88                 omap_cfg_reg(P20_1610_GPIO4);
  89         } else if (machine_is_omap_h3()) {
  90                 gpio = H3_GPIO_NUM;
  91                 omap_cfg_reg(W19_1610_GPIO48);
  92         } else if (machine_is_omap_h6300 ()) {
  93                 gpio = H6300_GPIO_NUM;
  94                 omap_cfg_reg(M14_1510_GPIO2);
  95         } else
  96                 return -ENODEV;
  97
  98         ts->irq = OMAP_GPIO_IRQ(gpio);
  99         if (omap_request_gpio(gpio) != 0) {
 100                 printk(KERN_ERR "hX_ts_init.c: Could not reserve GPIO!\n");
 101                 return -EINVAL;
 102         };
 103
 104         omap_set_gpio_direction(gpio, 1);
 105         ts->irq_type = SA_TRIGGER_FALLING;
 106         return 0;
 107 }
 108
 109 static void hx_ts_read(u16 * values)
 110 {
 111         s32 t, p = 0;
 112         int i;
 113
 114         /* Read X, Y, Z1 and Z2 */
 115         omap_tsc2101_reads(TOUCHSCREEN_DATA_REGISTERS_PAGE, TSC2101_TS_X,
 116                            values, OMAP_TSC2101_READ_MAX);
 117
 118         for (i = 0; i < OMAP_TSC2101_READ_MAX; i++)
 119                 values[i] &= TSC2101_MASKVAL;
 120
 121         /* Calculate Pressure */
 122         if (values[TSC2101_TS_Z1] != 0) {
 123                 t = ((OMAP_TSC2101_XRES * values[TSC2101_TS_X]) *
 124                      (values[TSC2101_TS_Z2] - values[TSC2101_TS_Z1]));
 125                 p = t / (u32) (TSC2101_PRESSUREVAL(values[TSC2101_TS_Z1]));
 126                 if (p < 0)
 127                         p = 0;
 128         }
 129
 130         values[TSC2101_TS_Z1] = p;
 131 }
 132
 133 static void hx_ts_enable(void)
 134 {
 135         int ret = omap_tsc2101_enable();
 136         if (ret) {
 137                 printk(KERN_ERR "FAILED TO INITIALIZE TSC CODEC\n");
 138                 return;
 139         }
 140
 141         /* PINTDAV is data available only */
 142         omap_tsc2101_write(TOUCHSCREEN_CONTROL_REGISTERS_PAGE,
 143                            TSC2101_TS_STATUS, TSC2101_DATA_AVAILABLE);
 144         /* disable buffer mode */
 145         omap_tsc2101_write(TOUCHSCREEN_CONTROL_REGISTERS_PAGE,
 146                            TSC2101_TS_BUFFER_CTRL, TSC2101_BUFFERMODE_DISABLE);
 147         /* use internal reference, 100 usec power-up delay,
 148          *        * power down between conversions, 1.25V internal reference */
 149         omap_tsc2101_write(TOUCHSCREEN_CONTROL_REGISTERS_PAGE,
 150                            TSC2101_TS_REF_CTRL, TSC2101_REF_POWERUP);
 151         /* enable touch detection, 84usec precharge time, 32 usec sense time */
 152         omap_tsc2101_write(TOUCHSCREEN_CONTROL_REGISTERS_PAGE,
 153                            TSC2101_TS_CONFIG_CTRL, TSC2101_ENABLE_TOUCHDETECT);
 154         /* 3 msec conversion delays  */
 155         omap_tsc2101_write(TOUCHSCREEN_CONTROL_REGISTERS_PAGE,
 156                            TSC2101_TS_PROG_DELAY, TSC2101_PRG_DELAY);
 157         /*
 158          * TSC2101-controlled conversions
 159          * 12-bit samples
 160          * continuous X,Y,Z1,Z2 scan mode
 161          * average (mean) 4 samples per coordinate
 162          * 1 MHz internal conversion clock
 163          * 500 usec panel voltage stabilization delay
 164          */
 165         omap_tsc2101_write(TOUCHSCREEN_CONTROL_REGISTERS_PAGE,
 166                            TSC2101_TS_ADC_CTRL, TSC2101_ADC_CONTROL);
 167
 168         return;
 169
 170 }
 171
 172 static void hx_ts_disable(void)
 173 {
 174         /* stop conversions and power down */
 175         omap_tsc2101_write(TOUCHSCREEN_CONTROL_REGISTERS_PAGE,
 176                            TSC2101_TS_ADC_CTRL, TSC2101_ADC_POWERDOWN);
 177         omap_tsc2101_disable();
 178 }
 179
 180 #ifdef  MODULE
 181 static void __exit hx_ts_remove(void)
 182 {
 183         if (machine_is_omap_h2())
 184                 omap_free_gpio(H2_GPIO_NUM);
 185         else if (machine_is_omap_h3())
 186                 omap_free_gpio(H3_GPIO_NUM);
 187         else if (machine_is_omap_h6300())
 188                 omap_free_gpio(H6300_GPIO_NUM);
 189 }
 190 #endif