1/* STMicroelectronics STMPE811 Touchscreen Driver 2 * 3 * (C) 2010 Luotao Fu <l.fu@pengutronix.de> 4 * All rights reserved. 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License as published by the 8 * Free Software Foundation; either version 2 of the License, or (at your 9 * option) any later version. 10 * 11 */ 12 13#include <linux/kernel.h> 14#include <linux/module.h> 15#include <linux/sched.h> 16#include <linux/interrupt.h> 17#include <linux/init.h> 18#include <linux/device.h> 19#include <linux/platform_device.h> 20#include <linux/input.h> 21#include <linux/slab.h> 22#include <linux/delay.h> 23#include <linux/i2c.h> 24#include <linux/workqueue.h> 25 26#include <linux/mfd/stmpe.h> 27 28/* Register layouts and functionalities are identical on all stmpexxx variants 29 * with touchscreen controller 30 */ 31#define STMPE_REG_INT_STA 0x0B 32#define STMPE_REG_ADC_CTRL1 0x20 33#define STMPE_REG_ADC_CTRL2 0x21 34#define STMPE_REG_TSC_CTRL 0x40 35#define STMPE_REG_TSC_CFG 0x41 36#define STMPE_REG_FIFO_TH 0x4A 37#define STMPE_REG_FIFO_STA 0x4B 38#define STMPE_REG_FIFO_SIZE 0x4C 39#define STMPE_REG_TSC_DATA_XYZ 0x52 40#define STMPE_REG_TSC_FRACTION_Z 0x56 41#define STMPE_REG_TSC_I_DRIVE 0x58 42 43#define OP_MOD_XYZ 0 44 45#define STMPE_TSC_CTRL_TSC_EN (1<<0) 46 47#define STMPE_FIFO_STA_RESET (1<<0) 48 49#define STMPE_IRQ_TOUCH_DET 0 50 51#define SAMPLE_TIME(x) ((x & 0xf) << 4) 52#define MOD_12B(x) ((x & 0x1) << 3) 53#define REF_SEL(x) ((x & 0x1) << 1) 54#define ADC_FREQ(x) (x & 0x3) 55#define AVE_CTRL(x) ((x & 0x3) << 6) 56#define DET_DELAY(x) ((x & 0x7) << 3) 57#define SETTLING(x) (x & 0x7) 58#define FRACTION_Z(x) (x & 0x7) 59#define I_DRIVE(x) (x & 0x1) 60#define OP_MODE(x) ((x & 0x7) << 1) 61 62#define STMPE_TS_NAME "stmpe-ts" 63#define XY_MASK 0xfff 64 65struct stmpe_touch { 66 struct stmpe *stmpe; 67 struct input_dev *idev; 68 struct delayed_work work; 69 struct device *dev; 70 u8 sample_time; 71 u8 mod_12b; 72 u8 ref_sel; 73 u8 adc_freq; 74 u8 ave_ctrl; 75 u8 touch_det_delay; 76 u8 settling; 77 u8 fraction_z; 78 u8 i_drive; 79}; 80 81static int __stmpe_reset_fifo(struct stmpe *stmpe) 82{ 83 int ret; 84 85 ret = stmpe_set_bits(stmpe, STMPE_REG_FIFO_STA, 86 STMPE_FIFO_STA_RESET, STMPE_FIFO_STA_RESET); 87 if (ret) 88 return ret; 89 90 return stmpe_set_bits(stmpe, STMPE_REG_FIFO_STA, 91 STMPE_FIFO_STA_RESET, 0); 92} 93 94static void stmpe_work(struct work_struct *work) 95{ 96 int int_sta; 97 u32 timeout = 40; 98 99 struct stmpe_touch *ts = 100 container_of(work, struct stmpe_touch, work.work); 101 102 int_sta = stmpe_reg_read(ts->stmpe, STMPE_REG_INT_STA); 103 104 while ((int_sta & (1 << STMPE_IRQ_TOUCH_DET)) && (timeout > 0)) { 105 timeout--; 106 int_sta = stmpe_reg_read(ts->stmpe, STMPE_REG_INT_STA); 107 udelay(100); 108 } 109 110 /* reset the FIFO before we report release event */ 111 __stmpe_reset_fifo(ts->stmpe); 112 113 input_report_abs(ts->idev, ABS_PRESSURE, 0); 114 input_sync(ts->idev); 115} 116 117static irqreturn_t stmpe_ts_handler(int irq, void *data) 118{ 119 u8 data_set[4]; 120 int x, y, z; 121 struct stmpe_touch *ts = data; 122 123 /* 124 * Cancel scheduled polling for release if we have new value 125 * available. Wait if the polling is already running. 126 */ 127 cancel_delayed_work_sync(&ts->work); 128 129 stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL, 130 STMPE_TSC_CTRL_TSC_EN, 0); 131 132 stmpe_block_read(ts->stmpe, STMPE_REG_TSC_DATA_XYZ, 4, data_set); 133 134 x = (data_set[0] << 4) | (data_set[1] >> 4); 135 y = ((data_set[1] & 0xf) << 8) | data_set[2]; 136 z = data_set[3]; 137 138 input_report_abs(ts->idev, ABS_X, x); 139 input_report_abs(ts->idev, ABS_Y, y); 140 input_report_abs(ts->idev, ABS_PRESSURE, z); 141 input_sync(ts->idev); 142 143 /* flush the FIFO after we have read out our values. */ 144 __stmpe_reset_fifo(ts->stmpe); 145 146 /* reenable the tsc */ 147 stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL, 148 STMPE_TSC_CTRL_TSC_EN, STMPE_TSC_CTRL_TSC_EN); 149 150 /* start polling for touch_det to detect release */ 151 schedule_delayed_work(&ts->work, HZ / 50); 152 153 return IRQ_HANDLED; 154} 155 156static int __devinit stmpe_init_hw(struct stmpe_touch *ts) 157{ 158 int ret; 159 u8 adc_ctrl1, adc_ctrl1_mask, tsc_cfg, tsc_cfg_mask; 160 struct stmpe *stmpe = ts->stmpe; 161 struct device *dev = ts->dev; 162 163 ret = stmpe_enable(stmpe, STMPE_BLOCK_TOUCHSCREEN | STMPE_BLOCK_ADC); 164 if (ret) { 165 dev_err(dev, "Could not enable clock for ADC and TS\n"); 166 return ret; 167 } 168 169 adc_ctrl1 = SAMPLE_TIME(ts->sample_time) | MOD_12B(ts->mod_12b) | 170 REF_SEL(ts->ref_sel); 171 adc_ctrl1_mask = SAMPLE_TIME(0xff) | MOD_12B(0xff) | REF_SEL(0xff); 172 173 ret = stmpe_set_bits(stmpe, STMPE_REG_ADC_CTRL1, 174 adc_ctrl1_mask, adc_ctrl1); 175 if (ret) { 176 dev_err(dev, "Could not setup ADC\n"); 177 return ret; 178 } 179 180 ret = stmpe_set_bits(stmpe, STMPE_REG_ADC_CTRL2, 181 ADC_FREQ(0xff), ADC_FREQ(ts->adc_freq)); 182 if (ret) { 183 dev_err(dev, "Could not setup ADC\n"); 184 return ret; 185 } 186 187 tsc_cfg = AVE_CTRL(ts->ave_ctrl) | DET_DELAY(ts->touch_det_delay) | 188 SETTLING(ts->settling); 189 tsc_cfg_mask = AVE_CTRL(0xff) | DET_DELAY(0xff) | SETTLING(0xff); 190 191 ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_CFG, tsc_cfg_mask, tsc_cfg); 192 if (ret) { 193 dev_err(dev, "Could not config touch\n"); 194 return ret; 195 } 196 197 ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_FRACTION_Z, 198 FRACTION_Z(0xff), FRACTION_Z(ts->fraction_z)); 199 if (ret) { 200 dev_err(dev, "Could not config touch\n"); 201 return ret; 202 } 203 204 ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_I_DRIVE, 205 I_DRIVE(0xff), I_DRIVE(ts->i_drive)); 206 if (ret) { 207 dev_err(dev, "Could not config touch\n"); 208 return ret; 209 } 210 211 /* set FIFO to 1 for single point reading */ 212 ret = stmpe_reg_write(stmpe, STMPE_REG_FIFO_TH, 1); 213 if (ret) { 214 dev_err(dev, "Could not set FIFO\n"); 215 return ret; 216 } 217 218 ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_CTRL, 219 OP_MODE(0xff), OP_MODE(OP_MOD_XYZ)); 220 if (ret) { 221 dev_err(dev, "Could not set mode\n"); 222 return ret; 223 } 224 225 return 0; 226} 227 228static int stmpe_ts_open(struct input_dev *dev) 229{ 230 struct stmpe_touch *ts = input_get_drvdata(dev); 231 int ret = 0; 232 233 ret = __stmpe_reset_fifo(ts->stmpe); 234 if (ret) 235 return ret; 236 237 return stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL, 238 STMPE_TSC_CTRL_TSC_EN, STMPE_TSC_CTRL_TSC_EN); 239} 240 241static void stmpe_ts_close(struct input_dev *dev) 242{ 243 struct stmpe_touch *ts = input_get_drvdata(dev); 244 245 cancel_delayed_work_sync(&ts->work); 246 247 stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL, 248 STMPE_TSC_CTRL_TSC_EN, 0); 249} 250 251static int __devinit stmpe_input_probe(struct platform_device *pdev) 252{ 253 struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent); 254 struct stmpe_platform_data *pdata = stmpe->pdata; 255 struct stmpe_touch *ts; 256 struct input_dev *idev; 257 struct stmpe_ts_platform_data *ts_pdata = NULL; 258 int ret = 0; 259 int ts_irq; 260 261 ts_irq = platform_get_irq_byname(pdev, "FIFO_TH"); 262 if (ts_irq < 0) 263 return ts_irq; 264 265 ts = kzalloc(sizeof(*ts), GFP_KERNEL); 266 if (!ts) 267 goto err_out; 268 269 idev = input_allocate_device(); 270 if (!idev) 271 goto err_free_ts; 272 273 platform_set_drvdata(pdev, ts); 274 ts->stmpe = stmpe; 275 ts->idev = idev; 276 ts->dev = &pdev->dev; 277 278 if (pdata) 279 ts_pdata = pdata->ts; 280 281 if (ts_pdata) { 282 ts->sample_time = ts_pdata->sample_time; 283 ts->mod_12b = ts_pdata->mod_12b; 284 ts->ref_sel = ts_pdata->ref_sel; 285 ts->adc_freq = ts_pdata->adc_freq; 286 ts->ave_ctrl = ts_pdata->ave_ctrl; 287 ts->touch_det_delay = ts_pdata->touch_det_delay; 288 ts->settling = ts_pdata->settling; 289 ts->fraction_z = ts_pdata->fraction_z; 290 ts->i_drive = ts_pdata->i_drive; 291 } 292 293 INIT_DELAYED_WORK(&ts->work, stmpe_work); 294 295 ret = request_threaded_irq(ts_irq, NULL, stmpe_ts_handler, 296 IRQF_ONESHOT, STMPE_TS_NAME, ts); 297 if (ret) { 298 dev_err(&pdev->dev, "Failed to request IRQ %d\n", ts_irq); 299 goto err_free_input; 300 } 301 302 ret = stmpe_init_hw(ts); 303 if (ret) 304 goto err_free_irq; 305 306 idev->name = STMPE_TS_NAME; 307 idev->id.bustype = BUS_I2C; 308 idev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); 309 idev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); 310 311 idev->open = stmpe_ts_open; 312 idev->close = stmpe_ts_close; 313 314 input_set_drvdata(idev, ts); 315 316 input_set_abs_params(idev, ABS_X, 0, XY_MASK, 0, 0); 317 input_set_abs_params(idev, ABS_Y, 0, XY_MASK, 0, 0); 318 input_set_abs_params(idev, ABS_PRESSURE, 0x0, 0xff, 0, 0); 319 320 ret = input_register_device(idev); 321 if (ret) { 322 dev_err(&pdev->dev, "Could not register input device\n"); 323 goto err_free_irq; 324 } 325 326 return ret; 327 328err_free_irq: 329 free_irq(ts_irq, ts); 330err_free_input: 331 input_free_device(idev); 332 platform_set_drvdata(pdev, NULL); 333err_free_ts: 334 kfree(ts); 335err_out: 336 return ret; 337} 338 339static int __devexit stmpe_ts_remove(struct platform_device *pdev) 340{ 341 struct stmpe_touch *ts = platform_get_drvdata(pdev); 342 unsigned int ts_irq = platform_get_irq_byname(pdev, "FIFO_TH"); 343 344 stmpe_disable(ts->stmpe, STMPE_BLOCK_TOUCHSCREEN); 345 346 free_irq(ts_irq, ts); 347 348 platform_set_drvdata(pdev, NULL); 349 350 input_unregister_device(ts->idev); 351 input_free_device(ts->idev); 352 353 kfree(ts); 354 355 return 0; 356} 357 358static struct platform_driver stmpe_ts_driver = { 359 .driver = { 360 .name = STMPE_TS_NAME, 361 .owner = THIS_MODULE, 362 }, 363 .probe = stmpe_input_probe, 364 .remove = __devexit_p(stmpe_ts_remove), 365}; 366 367static int __init stmpe_ts_init(void) 368{ 369 return platform_driver_register(&stmpe_ts_driver); 370} 371 372module_init(stmpe_ts_init); 373 374static void __exit stmpe_ts_exit(void) 375{ 376 platform_driver_unregister(&stmpe_ts_driver); 377} 378 379module_exit(stmpe_ts_exit); 380 381MODULE_AUTHOR("Luotao Fu <l.fu@pengutronix.de>"); 382MODULE_DESCRIPTION("STMPEXXX touchscreen driver"); 383MODULE_LICENSE("GPL"); 384MODULE_ALIAS("platform:" STMPE_TS_NAME); 385