1 /* 2 * Touchscreen driver for WM831x PMICs 3 * 4 * Copyright 2011 Wolfson Microelectronics plc. 5 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com> 6 * 7 * This program is free software; you can redistribute it and/or modify it 8 * under the terms of the GNU General Public License as published by the 9 * Free Software Foundation; either version 2 of the License, or (at your 10 * option) any later version. 11 */ 12 13 #include <linux/module.h> 14 #include <linux/moduleparam.h> 15 #include <linux/kernel.h> 16 #include <linux/init.h> 17 #include <linux/string.h> 18 #include <linux/pm.h> 19 #include <linux/input.h> 20 #include <linux/interrupt.h> 21 #include <linux/io.h> 22 #include <linux/mfd/wm831x/core.h> 23 #include <linux/mfd/wm831x/irq.h> 24 #include <linux/mfd/wm831x/pdata.h> 25 #include <linux/platform_device.h> 26 #include <linux/slab.h> 27 #include <linux/types.h> 28 29 /* 30 * R16424 (0x4028) - Touch Control 1 31 */ 32 #define WM831X_TCH_ENA 0x8000 /* TCH_ENA */ 33 #define WM831X_TCH_CVT_ENA 0x4000 /* TCH_CVT_ENA */ 34 #define WM831X_TCH_SLPENA 0x1000 /* TCH_SLPENA */ 35 #define WM831X_TCH_Z_ENA 0x0400 /* TCH_Z_ENA */ 36 #define WM831X_TCH_Y_ENA 0x0200 /* TCH_Y_ENA */ 37 #define WM831X_TCH_X_ENA 0x0100 /* TCH_X_ENA */ 38 #define WM831X_TCH_DELAY_MASK 0x00E0 /* TCH_DELAY - [7:5] */ 39 #define WM831X_TCH_DELAY_SHIFT 5 /* TCH_DELAY - [7:5] */ 40 #define WM831X_TCH_DELAY_WIDTH 3 /* TCH_DELAY - [7:5] */ 41 #define WM831X_TCH_RATE_MASK 0x001F /* TCH_RATE - [4:0] */ 42 #define WM831X_TCH_RATE_SHIFT 0 /* TCH_RATE - [4:0] */ 43 #define WM831X_TCH_RATE_WIDTH 5 /* TCH_RATE - [4:0] */ 44 45 /* 46 * R16425 (0x4029) - Touch Control 2 47 */ 48 #define WM831X_TCH_PD_WK 0x2000 /* TCH_PD_WK */ 49 #define WM831X_TCH_5WIRE 0x1000 /* TCH_5WIRE */ 50 #define WM831X_TCH_PDONLY 0x0800 /* TCH_PDONLY */ 51 #define WM831X_TCH_ISEL 0x0100 /* TCH_ISEL */ 52 #define WM831X_TCH_RPU_MASK 0x000F /* TCH_RPU - [3:0] */ 53 #define WM831X_TCH_RPU_SHIFT 0 /* TCH_RPU - [3:0] */ 54 #define WM831X_TCH_RPU_WIDTH 4 /* TCH_RPU - [3:0] */ 55 56 /* 57 * R16426-8 (0x402A-C) - Touch Data X/Y/X 58 */ 59 #define WM831X_TCH_PD 0x8000 /* TCH_PD1 */ 60 #define WM831X_TCH_DATA_MASK 0x0FFF /* TCH_DATA - [11:0] */ 61 #define WM831X_TCH_DATA_SHIFT 0 /* TCH_DATA - [11:0] */ 62 #define WM831X_TCH_DATA_WIDTH 12 /* TCH_DATA - [11:0] */ 63 64 struct wm831x_ts { 65 struct input_dev *input_dev; 66 struct wm831x *wm831x; 67 unsigned int data_irq; 68 unsigned int pd_irq; 69 bool pressure; 70 bool pen_down; 71 struct work_struct pd_data_work; 72 }; 73 74 static void wm831x_pd_data_work(struct work_struct *work) 75 { 76 struct wm831x_ts *wm831x_ts = 77 container_of(work, struct wm831x_ts, pd_data_work); 78 79 if (wm831x_ts->pen_down) { 80 enable_irq(wm831x_ts->data_irq); 81 dev_dbg(wm831x_ts->wm831x->dev, "IRQ PD->DATA done\n"); 82 } else { 83 enable_irq(wm831x_ts->pd_irq); 84 dev_dbg(wm831x_ts->wm831x->dev, "IRQ DATA->PD done\n"); 85 } 86 } 87 88 static irqreturn_t wm831x_ts_data_irq(int irq, void *irq_data) 89 { 90 struct wm831x_ts *wm831x_ts = irq_data; 91 struct wm831x *wm831x = wm831x_ts->wm831x; 92 static int data_types[] = { ABS_X, ABS_Y, ABS_PRESSURE }; 93 u16 data[3]; 94 int count; 95 int i, ret; 96 97 if (wm831x_ts->pressure) 98 count = 3; 99 else 100 count = 2; 101 102 wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1, 103 WM831X_TCHDATA_EINT, WM831X_TCHDATA_EINT); 104 105 ret = wm831x_bulk_read(wm831x, WM831X_TOUCH_DATA_X, count, 106 data); 107 if (ret != 0) { 108 dev_err(wm831x->dev, "Failed to read touch data: %d\n", 109 ret); 110 return IRQ_NONE; 111 } 112 113 /* 114 * We get a pen down reading on every reading, report pen up if any 115 * individual reading does so. 116 */ 117 wm831x_ts->pen_down = true; 118 for (i = 0; i < count; i++) { 119 if (!(data[i] & WM831X_TCH_PD)) { 120 wm831x_ts->pen_down = false; 121 continue; 122 } 123 input_report_abs(wm831x_ts->input_dev, data_types[i], 124 data[i] & WM831X_TCH_DATA_MASK); 125 } 126 127 if (!wm831x_ts->pen_down) { 128 /* Switch from data to pen down */ 129 dev_dbg(wm831x->dev, "IRQ DATA->PD\n"); 130 131 disable_irq_nosync(wm831x_ts->data_irq); 132 133 /* Don't need data any more */ 134 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, 135 WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | 136 WM831X_TCH_Z_ENA, 0); 137 138 /* Flush any final samples that arrived while reading */ 139 wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1, 140 WM831X_TCHDATA_EINT, WM831X_TCHDATA_EINT); 141 142 wm831x_bulk_read(wm831x, WM831X_TOUCH_DATA_X, count, data); 143 144 if (wm831x_ts->pressure) 145 input_report_abs(wm831x_ts->input_dev, 146 ABS_PRESSURE, 0); 147 148 input_report_key(wm831x_ts->input_dev, BTN_TOUCH, 0); 149 150 schedule_work(&wm831x_ts->pd_data_work); 151 } else { 152 input_report_key(wm831x_ts->input_dev, BTN_TOUCH, 1); 153 } 154 155 input_sync(wm831x_ts->input_dev); 156 157 return IRQ_HANDLED; 158 } 159 160 static irqreturn_t wm831x_ts_pen_down_irq(int irq, void *irq_data) 161 { 162 struct wm831x_ts *wm831x_ts = irq_data; 163 struct wm831x *wm831x = wm831x_ts->wm831x; 164 int ena = 0; 165 166 if (wm831x_ts->pen_down) 167 return IRQ_HANDLED; 168 169 disable_irq_nosync(wm831x_ts->pd_irq); 170 171 /* Start collecting data */ 172 if (wm831x_ts->pressure) 173 ena |= WM831X_TCH_Z_ENA; 174 175 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, 176 WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | WM831X_TCH_Z_ENA, 177 WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | ena); 178 179 wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1, 180 WM831X_TCHPD_EINT, WM831X_TCHPD_EINT); 181 182 wm831x_ts->pen_down = true; 183 184 /* Switch from pen down to data */ 185 dev_dbg(wm831x->dev, "IRQ PD->DATA\n"); 186 schedule_work(&wm831x_ts->pd_data_work); 187 188 return IRQ_HANDLED; 189 } 190 191 static int wm831x_ts_input_open(struct input_dev *idev) 192 { 193 struct wm831x_ts *wm831x_ts = input_get_drvdata(idev); 194 struct wm831x *wm831x = wm831x_ts->wm831x; 195 196 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, 197 WM831X_TCH_ENA | WM831X_TCH_CVT_ENA | 198 WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | 199 WM831X_TCH_Z_ENA, WM831X_TCH_ENA); 200 201 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, 202 WM831X_TCH_CVT_ENA, WM831X_TCH_CVT_ENA); 203 204 return 0; 205 } 206 207 static void wm831x_ts_input_close(struct input_dev *idev) 208 { 209 struct wm831x_ts *wm831x_ts = input_get_drvdata(idev); 210 struct wm831x *wm831x = wm831x_ts->wm831x; 211 212 /* Shut the controller down, disabling all other functionality too */ 213 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, 214 WM831X_TCH_ENA | WM831X_TCH_X_ENA | 215 WM831X_TCH_Y_ENA | WM831X_TCH_Z_ENA, 0); 216 217 /* Make sure any pending IRQs are done, the above will prevent 218 * new ones firing. 219 */ 220 synchronize_irq(wm831x_ts->data_irq); 221 synchronize_irq(wm831x_ts->pd_irq); 222 223 /* Make sure the IRQ completion work is quiesced */ 224 flush_work(&wm831x_ts->pd_data_work); 225 226 /* If we ended up with the pen down then make sure we revert back 227 * to pen detection state for the next time we start up. 228 */ 229 if (wm831x_ts->pen_down) { 230 disable_irq(wm831x_ts->data_irq); 231 enable_irq(wm831x_ts->pd_irq); 232 wm831x_ts->pen_down = false; 233 } 234 } 235 236 static int wm831x_ts_probe(struct platform_device *pdev) 237 { 238 struct wm831x_ts *wm831x_ts; 239 struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent); 240 struct wm831x_pdata *core_pdata = dev_get_platdata(pdev->dev.parent); 241 struct wm831x_touch_pdata *pdata = NULL; 242 struct input_dev *input_dev; 243 int error, irqf; 244 245 if (core_pdata) 246 pdata = core_pdata->touch; 247 248 wm831x_ts = devm_kzalloc(&pdev->dev, sizeof(struct wm831x_ts), 249 GFP_KERNEL); 250 input_dev = input_allocate_device(); 251 if (!wm831x_ts || !input_dev) { 252 error = -ENOMEM; 253 goto err_alloc; 254 } 255 256 wm831x_ts->wm831x = wm831x; 257 wm831x_ts->input_dev = input_dev; 258 INIT_WORK(&wm831x_ts->pd_data_work, wm831x_pd_data_work); 259 260 /* 261 * If we have a direct IRQ use it, otherwise use the interrupt 262 * from the WM831x IRQ controller. 263 */ 264 wm831x_ts->data_irq = wm831x_irq(wm831x, 265 platform_get_irq_byname(pdev, 266 "TCHDATA")); 267 if (pdata && pdata->data_irq) 268 wm831x_ts->data_irq = pdata->data_irq; 269 270 wm831x_ts->pd_irq = wm831x_irq(wm831x, 271 platform_get_irq_byname(pdev, "TCHPD")); 272 if (pdata && pdata->pd_irq) 273 wm831x_ts->pd_irq = pdata->pd_irq; 274 275 if (pdata) 276 wm831x_ts->pressure = pdata->pressure; 277 else 278 wm831x_ts->pressure = true; 279 280 /* Five wire touchscreens can't report pressure */ 281 if (pdata && pdata->fivewire) { 282 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, 283 WM831X_TCH_5WIRE, WM831X_TCH_5WIRE); 284 285 /* Pressure measurements are not possible for five wire mode */ 286 WARN_ON(pdata->pressure && pdata->fivewire); 287 wm831x_ts->pressure = false; 288 } else { 289 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, 290 WM831X_TCH_5WIRE, 0); 291 } 292 293 if (pdata) { 294 switch (pdata->isel) { 295 default: 296 dev_err(&pdev->dev, "Unsupported ISEL setting: %d\n", 297 pdata->isel); 298 /* Fall through */ 299 case 200: 300 case 0: 301 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, 302 WM831X_TCH_ISEL, 0); 303 break; 304 case 400: 305 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, 306 WM831X_TCH_ISEL, WM831X_TCH_ISEL); 307 break; 308 } 309 } 310 311 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, 312 WM831X_TCH_PDONLY, 0); 313 314 /* Default to 96 samples/sec */ 315 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, 316 WM831X_TCH_RATE_MASK, 6); 317 318 if (pdata && pdata->data_irqf) 319 irqf = pdata->data_irqf; 320 else 321 irqf = IRQF_TRIGGER_HIGH; 322 323 error = request_threaded_irq(wm831x_ts->data_irq, 324 NULL, wm831x_ts_data_irq, 325 irqf | IRQF_ONESHOT, 326 "Touchscreen data", wm831x_ts); 327 if (error) { 328 dev_err(&pdev->dev, "Failed to request data IRQ %d: %d\n", 329 wm831x_ts->data_irq, error); 330 goto err_alloc; 331 } 332 disable_irq(wm831x_ts->data_irq); 333 334 if (pdata && pdata->pd_irqf) 335 irqf = pdata->pd_irqf; 336 else 337 irqf = IRQF_TRIGGER_HIGH; 338 339 error = request_threaded_irq(wm831x_ts->pd_irq, 340 NULL, wm831x_ts_pen_down_irq, 341 irqf | IRQF_ONESHOT, 342 "Touchscreen pen down", wm831x_ts); 343 if (error) { 344 dev_err(&pdev->dev, "Failed to request pen down IRQ %d: %d\n", 345 wm831x_ts->pd_irq, error); 346 goto err_data_irq; 347 } 348 349 /* set up touch configuration */ 350 input_dev->name = "WM831x touchscreen"; 351 input_dev->phys = "wm831x"; 352 input_dev->open = wm831x_ts_input_open; 353 input_dev->close = wm831x_ts_input_close; 354 355 __set_bit(EV_ABS, input_dev->evbit); 356 __set_bit(EV_KEY, input_dev->evbit); 357 __set_bit(BTN_TOUCH, input_dev->keybit); 358 359 input_set_abs_params(input_dev, ABS_X, 0, 4095, 5, 0); 360 input_set_abs_params(input_dev, ABS_Y, 0, 4095, 5, 0); 361 if (wm831x_ts->pressure) 362 input_set_abs_params(input_dev, ABS_PRESSURE, 0, 4095, 5, 0); 363 364 input_set_drvdata(input_dev, wm831x_ts); 365 input_dev->dev.parent = &pdev->dev; 366 367 error = input_register_device(input_dev); 368 if (error) 369 goto err_pd_irq; 370 371 platform_set_drvdata(pdev, wm831x_ts); 372 return 0; 373 374 err_pd_irq: 375 free_irq(wm831x_ts->pd_irq, wm831x_ts); 376 err_data_irq: 377 free_irq(wm831x_ts->data_irq, wm831x_ts); 378 err_alloc: 379 input_free_device(input_dev); 380 381 return error; 382 } 383 384 static int wm831x_ts_remove(struct platform_device *pdev) 385 { 386 struct wm831x_ts *wm831x_ts = platform_get_drvdata(pdev); 387 388 free_irq(wm831x_ts->pd_irq, wm831x_ts); 389 free_irq(wm831x_ts->data_irq, wm831x_ts); 390 input_unregister_device(wm831x_ts->input_dev); 391 392 return 0; 393 } 394 395 static struct platform_driver wm831x_ts_driver = { 396 .driver = { 397 .name = "wm831x-touch", 398 .owner = THIS_MODULE, 399 }, 400 .probe = wm831x_ts_probe, 401 .remove = wm831x_ts_remove, 402 }; 403 module_platform_driver(wm831x_ts_driver); 404 405 /* Module information */ 406 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>"); 407 MODULE_DESCRIPTION("WM831x PMIC touchscreen driver"); 408 MODULE_LICENSE("GPL"); 409 MODULE_ALIAS("platform:wm831x-touch"); 410