Luotao Fu | f94add3 | 2010-07-02 14:10:29 +0200 | [diff] [blame] | 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 | |
| 65 | struct 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 | |
| 81 | static 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 | |
| 94 | static 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 | /* |
| 105 | * touch_det sometimes get desasserted or just get stuck. This appears |
| 106 | * to be a silicon bug, We still have to clearify this with the |
| 107 | * manufacture. As a workaround We release the key anyway if the |
| 108 | * touch_det keeps coming in after 4ms, while the FIFO contains no value |
| 109 | * during the whole time. |
| 110 | */ |
| 111 | while ((int_sta & (1 << STMPE_IRQ_TOUCH_DET)) && (timeout > 0)) { |
| 112 | timeout--; |
| 113 | int_sta = stmpe_reg_read(ts->stmpe, STMPE_REG_INT_STA); |
| 114 | udelay(100); |
| 115 | } |
| 116 | |
| 117 | /* reset the FIFO before we report release event */ |
| 118 | __stmpe_reset_fifo(ts->stmpe); |
| 119 | |
| 120 | input_report_abs(ts->idev, ABS_PRESSURE, 0); |
| 121 | input_sync(ts->idev); |
| 122 | } |
| 123 | |
| 124 | static irqreturn_t stmpe_ts_handler(int irq, void *data) |
| 125 | { |
| 126 | u8 data_set[4]; |
| 127 | int x, y, z; |
| 128 | struct stmpe_touch *ts = data; |
| 129 | |
| 130 | /* |
| 131 | * Cancel scheduled polling for release if we have new value |
| 132 | * available. Wait if the polling is already running. |
| 133 | */ |
| 134 | cancel_delayed_work_sync(&ts->work); |
| 135 | |
| 136 | /* |
| 137 | * The FIFO sometimes just crashes and stops generating interrupts. This |
| 138 | * appears to be a silicon bug. We still have to clearify this with |
| 139 | * the manufacture. As a workaround we disable the TSC while we are |
| 140 | * collecting data and flush the FIFO after reading |
| 141 | */ |
| 142 | stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL, |
| 143 | STMPE_TSC_CTRL_TSC_EN, 0); |
| 144 | |
| 145 | stmpe_block_read(ts->stmpe, STMPE_REG_TSC_DATA_XYZ, 4, data_set); |
| 146 | |
| 147 | x = (data_set[0] << 4) | (data_set[1] >> 4); |
| 148 | y = ((data_set[1] & 0xf) << 8) | data_set[2]; |
| 149 | z = data_set[3]; |
| 150 | |
| 151 | input_report_abs(ts->idev, ABS_X, x); |
| 152 | input_report_abs(ts->idev, ABS_Y, y); |
| 153 | input_report_abs(ts->idev, ABS_PRESSURE, z); |
| 154 | input_sync(ts->idev); |
| 155 | |
| 156 | /* flush the FIFO after we have read out our values. */ |
| 157 | __stmpe_reset_fifo(ts->stmpe); |
| 158 | |
| 159 | /* reenable the tsc */ |
| 160 | stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL, |
| 161 | STMPE_TSC_CTRL_TSC_EN, STMPE_TSC_CTRL_TSC_EN); |
| 162 | |
| 163 | /* start polling for touch_det to detect release */ |
| 164 | schedule_delayed_work(&ts->work, HZ / 50); |
| 165 | |
| 166 | return IRQ_HANDLED; |
| 167 | } |
| 168 | |
| 169 | static int __devinit stmpe_init_hw(struct stmpe_touch *ts) |
| 170 | { |
| 171 | int ret; |
| 172 | u8 adc_ctrl1, adc_ctrl1_mask, tsc_cfg, tsc_cfg_mask; |
| 173 | struct stmpe *stmpe = ts->stmpe; |
| 174 | struct device *dev = ts->dev; |
| 175 | |
| 176 | ret = stmpe_enable(stmpe, STMPE_BLOCK_TOUCHSCREEN | STMPE_BLOCK_ADC); |
| 177 | if (ret) { |
| 178 | dev_err(dev, "Could not enable clock for ADC and TS\n"); |
| 179 | return ret; |
| 180 | } |
| 181 | |
| 182 | adc_ctrl1 = SAMPLE_TIME(ts->sample_time) | MOD_12B(ts->mod_12b) | |
| 183 | REF_SEL(ts->ref_sel); |
| 184 | adc_ctrl1_mask = SAMPLE_TIME(0xff) | MOD_12B(0xff) | REF_SEL(0xff); |
| 185 | |
| 186 | ret = stmpe_set_bits(stmpe, STMPE_REG_ADC_CTRL1, |
| 187 | adc_ctrl1_mask, adc_ctrl1); |
| 188 | if (ret) { |
| 189 | dev_err(dev, "Could not setup ADC\n"); |
| 190 | return ret; |
| 191 | } |
| 192 | |
| 193 | ret = stmpe_set_bits(stmpe, STMPE_REG_ADC_CTRL2, |
| 194 | ADC_FREQ(0xff), ADC_FREQ(ts->adc_freq)); |
| 195 | if (ret) { |
| 196 | dev_err(dev, "Could not setup ADC\n"); |
| 197 | return ret; |
| 198 | } |
| 199 | |
| 200 | tsc_cfg = AVE_CTRL(ts->ave_ctrl) | DET_DELAY(ts->touch_det_delay) | |
| 201 | SETTLING(ts->settling); |
| 202 | tsc_cfg_mask = AVE_CTRL(0xff) | DET_DELAY(0xff) | SETTLING(0xff); |
| 203 | |
| 204 | ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_CFG, tsc_cfg_mask, tsc_cfg); |
| 205 | if (ret) { |
| 206 | dev_err(dev, "Could not config touch\n"); |
| 207 | return ret; |
| 208 | } |
| 209 | |
| 210 | ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_FRACTION_Z, |
| 211 | FRACTION_Z(0xff), FRACTION_Z(ts->fraction_z)); |
| 212 | if (ret) { |
| 213 | dev_err(dev, "Could not config touch\n"); |
| 214 | return ret; |
| 215 | } |
| 216 | |
| 217 | ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_I_DRIVE, |
| 218 | I_DRIVE(0xff), I_DRIVE(ts->i_drive)); |
| 219 | if (ret) { |
| 220 | dev_err(dev, "Could not config touch\n"); |
| 221 | return ret; |
| 222 | } |
| 223 | |
| 224 | /* set FIFO to 1 for single point reading */ |
| 225 | ret = stmpe_reg_write(stmpe, STMPE_REG_FIFO_TH, 1); |
| 226 | if (ret) { |
| 227 | dev_err(dev, "Could not set FIFO\n"); |
| 228 | return ret; |
| 229 | } |
| 230 | |
| 231 | ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_CTRL, |
| 232 | OP_MODE(0xff), OP_MODE(OP_MOD_XYZ)); |
| 233 | if (ret) { |
| 234 | dev_err(dev, "Could not set mode\n"); |
| 235 | return ret; |
| 236 | } |
| 237 | |
| 238 | return 0; |
| 239 | } |
| 240 | |
| 241 | static int stmpe_ts_open(struct input_dev *dev) |
| 242 | { |
| 243 | struct stmpe_touch *ts = input_get_drvdata(dev); |
| 244 | int ret = 0; |
| 245 | |
| 246 | ret = __stmpe_reset_fifo(ts->stmpe); |
| 247 | if (ret) |
| 248 | return ret; |
| 249 | |
| 250 | return stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL, |
| 251 | STMPE_TSC_CTRL_TSC_EN, STMPE_TSC_CTRL_TSC_EN); |
| 252 | } |
| 253 | |
| 254 | static void stmpe_ts_close(struct input_dev *dev) |
| 255 | { |
| 256 | struct stmpe_touch *ts = input_get_drvdata(dev); |
| 257 | |
| 258 | cancel_delayed_work_sync(&ts->work); |
| 259 | |
| 260 | stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL, |
| 261 | STMPE_TSC_CTRL_TSC_EN, 0); |
| 262 | } |
| 263 | |
| 264 | static int __devinit stmpe_input_probe(struct platform_device *pdev) |
| 265 | { |
| 266 | struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent); |
| 267 | struct stmpe_platform_data *pdata = stmpe->pdata; |
| 268 | struct stmpe_touch *ts; |
| 269 | struct input_dev *idev; |
| 270 | struct stmpe_ts_platform_data *ts_pdata = NULL; |
Axel Lin | cdd1947 | 2010-09-02 19:54:27 -0700 | [diff] [blame] | 271 | int ret; |
Kulikov Vasiliy | 3faeb35 | 2010-07-15 22:43:54 +0400 | [diff] [blame] | 272 | int ts_irq; |
Luotao Fu | f94add3 | 2010-07-02 14:10:29 +0200 | [diff] [blame] | 273 | |
| 274 | ts_irq = platform_get_irq_byname(pdev, "FIFO_TH"); |
| 275 | if (ts_irq < 0) |
| 276 | return ts_irq; |
| 277 | |
| 278 | ts = kzalloc(sizeof(*ts), GFP_KERNEL); |
Axel Lin | cdd1947 | 2010-09-02 19:54:27 -0700 | [diff] [blame] | 279 | if (!ts) { |
| 280 | ret = -ENOMEM; |
Luotao Fu | f94add3 | 2010-07-02 14:10:29 +0200 | [diff] [blame] | 281 | goto err_out; |
Axel Lin | cdd1947 | 2010-09-02 19:54:27 -0700 | [diff] [blame] | 282 | } |
Luotao Fu | f94add3 | 2010-07-02 14:10:29 +0200 | [diff] [blame] | 283 | |
| 284 | idev = input_allocate_device(); |
Axel Lin | cdd1947 | 2010-09-02 19:54:27 -0700 | [diff] [blame] | 285 | if (!idev) { |
| 286 | ret = -ENOMEM; |
Luotao Fu | f94add3 | 2010-07-02 14:10:29 +0200 | [diff] [blame] | 287 | goto err_free_ts; |
Axel Lin | cdd1947 | 2010-09-02 19:54:27 -0700 | [diff] [blame] | 288 | } |
Luotao Fu | f94add3 | 2010-07-02 14:10:29 +0200 | [diff] [blame] | 289 | |
| 290 | platform_set_drvdata(pdev, ts); |
| 291 | ts->stmpe = stmpe; |
| 292 | ts->idev = idev; |
| 293 | ts->dev = &pdev->dev; |
| 294 | |
| 295 | if (pdata) |
| 296 | ts_pdata = pdata->ts; |
| 297 | |
| 298 | if (ts_pdata) { |
| 299 | ts->sample_time = ts_pdata->sample_time; |
| 300 | ts->mod_12b = ts_pdata->mod_12b; |
| 301 | ts->ref_sel = ts_pdata->ref_sel; |
| 302 | ts->adc_freq = ts_pdata->adc_freq; |
| 303 | ts->ave_ctrl = ts_pdata->ave_ctrl; |
| 304 | ts->touch_det_delay = ts_pdata->touch_det_delay; |
| 305 | ts->settling = ts_pdata->settling; |
| 306 | ts->fraction_z = ts_pdata->fraction_z; |
| 307 | ts->i_drive = ts_pdata->i_drive; |
| 308 | } |
| 309 | |
| 310 | INIT_DELAYED_WORK(&ts->work, stmpe_work); |
| 311 | |
| 312 | ret = request_threaded_irq(ts_irq, NULL, stmpe_ts_handler, |
| 313 | IRQF_ONESHOT, STMPE_TS_NAME, ts); |
| 314 | if (ret) { |
| 315 | dev_err(&pdev->dev, "Failed to request IRQ %d\n", ts_irq); |
| 316 | goto err_free_input; |
| 317 | } |
| 318 | |
| 319 | ret = stmpe_init_hw(ts); |
| 320 | if (ret) |
| 321 | goto err_free_irq; |
| 322 | |
| 323 | idev->name = STMPE_TS_NAME; |
| 324 | idev->id.bustype = BUS_I2C; |
| 325 | idev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); |
| 326 | idev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); |
| 327 | |
| 328 | idev->open = stmpe_ts_open; |
| 329 | idev->close = stmpe_ts_close; |
| 330 | |
| 331 | input_set_drvdata(idev, ts); |
| 332 | |
| 333 | input_set_abs_params(idev, ABS_X, 0, XY_MASK, 0, 0); |
| 334 | input_set_abs_params(idev, ABS_Y, 0, XY_MASK, 0, 0); |
| 335 | input_set_abs_params(idev, ABS_PRESSURE, 0x0, 0xff, 0, 0); |
| 336 | |
| 337 | ret = input_register_device(idev); |
| 338 | if (ret) { |
| 339 | dev_err(&pdev->dev, "Could not register input device\n"); |
| 340 | goto err_free_irq; |
| 341 | } |
| 342 | |
| 343 | return ret; |
| 344 | |
| 345 | err_free_irq: |
| 346 | free_irq(ts_irq, ts); |
| 347 | err_free_input: |
| 348 | input_free_device(idev); |
| 349 | platform_set_drvdata(pdev, NULL); |
| 350 | err_free_ts: |
| 351 | kfree(ts); |
| 352 | err_out: |
| 353 | return ret; |
| 354 | } |
| 355 | |
| 356 | static int __devexit stmpe_ts_remove(struct platform_device *pdev) |
| 357 | { |
| 358 | struct stmpe_touch *ts = platform_get_drvdata(pdev); |
| 359 | unsigned int ts_irq = platform_get_irq_byname(pdev, "FIFO_TH"); |
| 360 | |
| 361 | stmpe_disable(ts->stmpe, STMPE_BLOCK_TOUCHSCREEN); |
| 362 | |
| 363 | free_irq(ts_irq, ts); |
| 364 | |
| 365 | platform_set_drvdata(pdev, NULL); |
| 366 | |
| 367 | input_unregister_device(ts->idev); |
Luotao Fu | f94add3 | 2010-07-02 14:10:29 +0200 | [diff] [blame] | 368 | |
| 369 | kfree(ts); |
| 370 | |
| 371 | return 0; |
| 372 | } |
| 373 | |
| 374 | static struct platform_driver stmpe_ts_driver = { |
| 375 | .driver = { |
| 376 | .name = STMPE_TS_NAME, |
| 377 | .owner = THIS_MODULE, |
| 378 | }, |
| 379 | .probe = stmpe_input_probe, |
| 380 | .remove = __devexit_p(stmpe_ts_remove), |
| 381 | }; |
| 382 | |
| 383 | static int __init stmpe_ts_init(void) |
| 384 | { |
| 385 | return platform_driver_register(&stmpe_ts_driver); |
| 386 | } |
| 387 | |
| 388 | module_init(stmpe_ts_init); |
| 389 | |
| 390 | static void __exit stmpe_ts_exit(void) |
| 391 | { |
| 392 | platform_driver_unregister(&stmpe_ts_driver); |
| 393 | } |
| 394 | |
| 395 | module_exit(stmpe_ts_exit); |
| 396 | |
| 397 | MODULE_AUTHOR("Luotao Fu <l.fu@pengutronix.de>"); |
| 398 | MODULE_DESCRIPTION("STMPEXXX touchscreen driver"); |
| 399 | MODULE_LICENSE("GPL"); |
| 400 | MODULE_ALIAS("platform:" STMPE_TS_NAME); |